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Nurse’s Manual
of Laboratory and
Diagnostic Tests
EDITION

Bonita Morrow Cavanaugh, PhD, RN
Clinical Nurse Specialist
Nursing Education
The Children’s Hospital
Denver, Colorado
Clinical Faculty
University of Colorado
Health Sciences Center
School of Nursing
Denver, Colorado
Affiliate Professor
University of Northern Colorado
School of Nursing
Greeley, Colorado

F.A. Davis Company • Philadelphia

F. A. Davis Company
1915 Arch Street
Philadelphia, PA 19103
www.fadavis.com
Copyright © 2003 by F. A. Davis Company
Copyright © 1999, 1995, 1989 by F. A. Davis Company. All rights reserved. This book is protected by copyright. No part of it
may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without written permission from the publisher.
Printed in the United States of America
Last digit indicates print number: 10 9 8 7 6 5 4 3 2 1
Publisher: Lisa Deitch
Developmental Editor: Diane Blodgett
Cover Designer: Louis J. Forgione
As new scientific information becomes available through basic and clinical research, recommended treatments and drug
therapies undergo changes. The author and publisher have done everything possible to make this book accurate, up to date,
and in accord with accepted standards at the time of publication. The author, editors, and publisher are not responsible for
errors or omissions or for consequences from application of the book, and make no warranty, expressed or implied, in regard
to the contents of the book. Any practice described in this book should be applied by the reader in accordance with professional
standards of care used in regard to the unique circumstances that may apply in each situation. The reader is advised always to
check product information (package inserts) for changes and new information regarding dose and contraindications before
administering any drug. Caution is especially urged when using new or infrequently ordered drugs.
Library of Congress Cataloging-in-Publication Data
Cavanaugh, Bonita Morrow, 1952–
Nurse’s manual of laboratory and diagnostic tests. – 4th ed. /
Bonita Morrow Cavanaugh.
p. cm.
Rev. ed. of: Nurse’s manual of laboratory and diagnostic tests /
Juanita Watson. 3rd. ed. c1995.
Includes bibliographical references and index.
ISBN 0-8036-1055-6 (pbk.)
1. Diagnosis, Laboratory —Handbooks, manuals, etc. 2. Nursing-Handbook, manuals, etc. I. Watson, Juanita,
1946–
Nurse’s manual of laboratory and diagnostic tests. II. Title.
[DNLM: 1. Laboratory Techniques and Procedures nurses’ instruction
handbooks. QY 39 C377n 1999]
RT48.5.W38 1999
616.07′5—dc21
DNLM/DLC
for Library of Congress
98-50920
CIP
Authorization to photocopy items for internal or personal use, or the internal or personal use of specific clients, is granted by
F. A. Davis Company for users registered with the Copyright Clearance Center (CCC) Transactional Reporting Service, provided
that the fee of $.10 per copy is paid directly to CCC, 222 Rosewood Drive, Danvers, MA 01923. For those organizations that
have been granted a photocopy license by CCC, a separate system of payment has been arranged. The fee code for users of the
Transactional Reporting Service is: 8036-1055/03 0 + $.10.

To Laurie O’Neil Good, the finest nurse I have ever known.
Love,
Bonnie

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Preface

This book is designed to provide both students and practitioners of nursing with the information they need to care for individuals undergoing laboratory and diagnostic tests and procedures. The content is presented as a guiding reference for planning care, providing specific
interventions, and evaluating outcomes of nursing care.
In this edition, the background information and description of the test or procedure are
followed directly by the clinical applications data, starting with reference values, for each test or
group of tests.
The introductory sections include the anatomic, physiological, and pathophysiological
content necessary for a thorough understanding of the purpose of and indications for specific
tests and procedures. The inclusion of this information makes this book unlike many other
references on this subject matter. This feature enhances the integration of basic science knowledge with an understanding of and application to diagnostic testing. This is extremely helpful
for nursing students in developing critical thinking and clinical judgment.
For each test or study within the respective sections, reference values, including variations
related to age or gender, are provided. Critical values, where appropriate, are highlighted. Both
conventional units and international units are provided. Readers are encouraged to be aware of
some variation in laboratory values from agency to agency.
For all tests, interfering factors are noted where appropriate. Contraindications and Nursing
Alerts are included to provide information crucial to safe and reliable testing and nursing care.
Other features of this manual that contribute to its practical use are presentation of detailed
content in tabular format when appropriate and the use of appendices to provide essential
information applicable to most, if not all, tests and procedures.
Every effort has been made to include tests and procedures currently in use in practice
settings. It is recognized that newer tests and procedures may have become available after this
manuscript was prepared. Readers are encouraged to keep abreast of current literature and
consult with laboratories and agencies in their area for new developments in the field of diagnostic tests.
BONITA MORROW CAVANAUGH

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Acknowledgments

This book would not have been possible without the help, support, and encouragement of a
number of people. Special appreciation is due to the staff of the F. A. Davis Company. I am
particularly indebted to Lisa Deitch, Publisher, for her major contribution in developing the
unique format of this text, for her encouragement, and for always being available for help when
I needed it. I would also like to acknowledge Robert Martone, Nursing Publisher, who encouraged me to pursue this project, and Robert H. Craven, Jr., President, for his support and
patience as the book evolved. Special thanks are also due to Ruth De George, Editorial Assistant,
and Michele Reese, Editorial Aide, for their invaluable assistance. Many other individuals at the
F. A. Davis Company contributed to the production of this book, and I wish to extend to all of
them my sincere appreciation for their expertise and dedication to the high standards necessary
to produce a good book. Special recognition in this regard is due to Jessica Howie Martin,
Production Editor, and Bob Butler, Director of Production.
I thank the consultants who served as reviewers of the manuscript for their thoroughness and
generosity in sharing their ideas and suggestions. Your comments proved invaluable! Finally, a
special thanks to those family members, friends, and associates who offered and gave their
support, patience, and encouragement.
B.M.C.

vii

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Consultants

Janice Brownlee, BScN, MAEd

Dolores Philpot, BSMT, AND, MSN

Professor
Canadore College of Applied Arts and
Technology
North Bay, Ontario, Canada

Instructor
University of Tennessee
Knoxville, Tennessee

Sylvan L. Settle, RN
Marie Colucci, BS, MS, EdD
Associate Professor
Riverside Community College
Riverside, California

Vocational Teacher
Tennessee Technology Center
Memphis, Tennessee

Joyce Taylor, RN, MSN, DSN, BA
Mary Jo Goolsby, MSN, ARNP, EdD
Instructor
Florida State University
Tallahassee, Florida

Associate Professor
Henderson State University
Arkadelphia, Arkansas

Shelley M. Tiffin, ART (CSMLS), BMLSc
Shelby Hawk, RN, MSN
Instructor
Mid Michigan Community College
Harrison, Michigan

Priscilla Innocent, RN, MSN
Associate Professor
Indiana Wesleyan University
Marion, Indiana

Dr. Fran Keen, RN, DNSc

Bachelor of Medical Laboratory Science
Program
Department of Pathology and Laboratory
Medicine
University of British Columbia
Vancouver, British Columbia, Canada

Donna Yancey, BSN, MSN, DNS
Assistant Professor
Purdue University
West Lafayette, Indiana

Associate Professor
University of Miami
Coral Gables, Florida

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Contents

SECTION I •

Laboratory Tests, 1

CHAPTER 1

Hematology and Tests of Hematopoietic Function ......................................................................3
CHAPTER 2

Hemostasis and Tests of Hemostatic Functions ........................................................................39
CHAPTER 3

Immunology and Immunologic Testing ........................................................................................60
CHAPTER 4

Immunohematology and Blood Banking......................................................................................96
CHAPTER 5

Blood Chemistry..............................................................................................................................103
CHAPTER 6

Studies of Urine ..............................................................................................................................221
CHAPTER 7

Sputum Analysis ............................................................................................................................268
CHAPTER 8

Cerebrospinal Fluid Analysis ......................................................................................................274
CHAPTER 9

Analysis of Effusions ....................................................................................................................283
CHAPTER 10

Amniotic Fluid Analysis ................................................................................................................297
CHAPTER 11

Semen Analysis ..............................................................................................................................305
CHAPTER 12

Analysis of Gastric and Duodenal Secretions..........................................................................311

xii

Contents
CHAPTER 13

Fecal Analysis ................................................................................................................................321
CHAPTER 14

Analysis of Cells and Tissues ......................................................................................................332
CHAPTER 15

Culture and Sensitivity Tests........................................................................................................352

SECTION II •

Diagnostic Tests and Procedures, 361

CHAPTER 16

Endoscopic Studies........................................................................................................................363
CHAPTER 17

Radiologic Studies ........................................................................................................................397
CHAPTER 18

Radiologic Angiography Studies ................................................................................................438
CHAPTER 19

Ultrasound Studies ........................................................................................................................458
CHAPTER 20

Nuclear Scan and Laboratory Studies ......................................................................................482
CHAPTER 21

Non-Nuclear Scan Studies ..........................................................................................................528
CHAPTER 22

Manometric Studies ......................................................................................................................545
CHAPTER 23

Electrophysiologic Studies ..........................................................................................................558
CHAPTER 24

Studies of Specific Organs or Systems......................................................................................577
CHAPTER 25

Skin Tests ........................................................................................................................................615
APPENDICES
APPENDIX I

Obtaining Various Types of Blood Specimens..........................................................................625
APPENDIX II

Obtaining Various Types of Urine Specimens ..........................................................................631
APPENDIX III

Guidelines for Isolation Precautions in Hospitals ..................................................................634
APPENDIX IV

Units of Measurement (Including SI Units) ..............................................................................636

Contents
APPENDIX V

Profile or Panel Groupings and Laboratory Tests ....................................................................644
APPENDIX VI

Nursing Care Plan for Individuals Experiencing
Laboratory and Diagnostic Testing ............................................................................................649
INDEX

..............................................................................................................................................651

xiii

SECTION

Laboratory
Tests

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CHAPTER

Hematology and Tests of
Hematopoietic Function
TESTS COVERED
Bone Marrow Examination, 7
Reticulocyte Count, 9
Iron Studies, 11
Vitamin B12 and Folic Acid Studies, 13
Complete Blood Count, 14
Erythrocyte (RBC) Count, 20
Hematocrit, 21
Hemoglobin, 21
Red Blood Cell Indices, 22

Stained Red Blood Cell
Examination, 24
Hemoglobin Electrophoresis, 26
Osmotic Fragility, 29
Red Blood Cell Enzymes, 30
Erythrocyte Sedimentation Rate, 31
White Blood Cell Count, 33
Differential White Blood Cell Count, 34
White Blood Cell Enzymes, 37

INTRODUCTION Blood constitutes 6 to 8 percent of total body weight. In terms of
volume, women have 4.5 to 5.5 L of blood and men 5 to 6 L. In infants and children, blood
volume is 50 to 75 mL/kg in girls and 52 to 83 mL/kg in boys. The principal functions of blood
are the transport of oxygen, nutrients, and hormones to all tissues and the removal of metabolic wastes to the organs of excretion. Additional functions of blood are (1) regulation of
temperature by transfer of heat to the skin for dissipation by radiation and convection, (2)
regulation of the pH of body fluids through the buffer systems and facilitation of excretion of
acids and bases, and (3) defense against infection by transportation of antibodies and other
substances as needed.
Blood consists of a fluid portion, called plasma, and a solid portion that includes red blood
cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes). Plasma makes
up 45 to 60 percent of blood volume and is composed of water (90 percent), amino acids,
proteins, carbohydrates, lipids, vitamins, hormones, electrolytes, and cellular wastes.1 Of the
“solid” or cellular portion of the blood, more than 99 percent consists of red blood cells.
Leukocytes and thrombocytes, although functionally essential, occupy a relatively small portion
of the total blood cell mass.2
Erythrocytes remain within the blood throughout their normal life span of 120 days, transporting oxygen in the hemoglobin component and carrying away carbon dioxide. Leukocytes,
while they are in the blood, are merely in transit, because they perform their functions in body
tissue. Platelets exert their effects at the walls of blood vessels, performing no known function
in the bloodstream itself.3
Hematology is traditionally limited to the study of the cellular elements of the blood, the
production of these elements, and the physiological derangements that affect their functions.
Hematologists also are concerned with blood volume, the flow properties of blood, and the
physical relationships of red cells and plasma. The numerous substances dissolved or suspended
in plasma fall within the province of other laboratory disciplines.4
3

SECTION I—Laboratory

Tests

HEMATOPOIESIS
Hematopoiesis is the process of blood cell formation.
In normal, healthy adults, blood cells are manufactured in the red marrow of relatively few bones,
notably the sternum, ribs, vertebral bodies, pelvic
bones, and proximal portions of the humerus and
the femur. This production is in contrast to that
taking place in the embryo, in which blood cells are
derived from the yolk sac mesenchyme. As the fetus
develops, the liver, the spleen, and the marrow cavities of nearly all bones become active hematopoietic
sites (Fig. 1–1). In the newborn, hematopoiesis
occurs primarily in the red marrow, which is found
in most bones at that stage of development.
Beginning at about age 5 years, the red marrow is
gradually replaced by yellowish fat-storage cells
(yellow marrow), which are inactive in the
hematopoietic process. By adulthood, blood cell
production normally occurs in only those bones that
retain red marrow activity.5
Adult reticuloendothelial cells retain the potential
for hematopoiesis, although in the healthy state
reserve sites are not activated. Under conditions of
hematopoietic stress in later life, the liver, the spleen,
and an expanded bone marrow may resume the
production of blood cells.
All blood cells are believed to be derived from the
pluripotential stem cell,6 an immature cell with the

capability of becoming an erythrocyte, a leukocyte,
or a thrombocyte. In the adult, stem cells in
hematopoietic sites undergo a series of divisions and
maturational changes to form the mature cells
found in the blood (Fig. 1–2). As they achieve the
“blast” stage, stem cells are committed to becoming
a specific type of blood cell. This theory also explains
the origin of the several types of white blood cells
(neutrophils, monocytes, eosinophils, basophils, and
lymphocytes). As the cells mature, they lose their
ability to reproduce and cannot further divide to
replace themselves. Thus, there is a need for continuous hematopoietic activity to replenish worn-out
or damaged blood cells.
Erythropoiesis, the production of red blood cells
(RBCs), and leukopoiesis, the production of white
blood cells (WBCs), are components of the
hematopoietic process. Erythropoiesis maintains a
population of approximately 25 1012 circulating
RBCs, or an average of 5 million erythrocytes per
cubic millimeter of blood. The production rate is
about 2 million cells per second, or 35 trillion cells
per day. With maximum stimulation, this rate can be
increased sixfold to eightfold, or one volume per day
equivalent to the cells contained in 0.5 pt of whole
blood.
The level of tissue oxygenation regulates the
production of RBCs; that is, erythropoiesis occurs in
response to tissue hypoxia. Hypoxia does not,

Figure 1–1. Location of active marrow growth in the fetus and adult. (From Hillman, RS, and Finch, CA: Red Cell
Manual, ed 7. FA Davis, Philadelphia, 1996, p 2, with permission.)

CHAPTER 1—Hematology

and Tests of Hematopoietic Function

Image/Text rights unavailable

however, directly stimulate the bone marrow.
Instead, RBC production occurs in response to
erythropoietin, precursors of which are found primarily in the kidney and to a lesser extent in the liver.
When the renal oxygen level falls, an enzyme, renal
erythropoietic factor, is secreted. This enzyme reacts
with a plasma protein to form erythropoietin, which
subsequently stimulates the bone marrow to
produce more RBCs. Specifically, erythropoietin (1)
accelerates production, differentiation, and maturaTABLE 1–1

•

tion of erythrocytes; (2) reduces the time required
for cells to enter the circulation, thereby increasing
the number of circulating immature erythrocytes
such as reticulocytes (see Fig. 1–2); and (3) facilitates
the incorporation of iron into RBCs. When the
number of produced erythrocytes meets the body’s
tissue oxygenation needs, erythropoietin release and
RBC production are reduced. Table 1–1 lists causes
of tissue hypoxia that may stimulate the release of
erythropoietin.

Causes of Tissue Hypoxia That May Stimulate
Erythropoietin Release

Acute blood loss
Impaired oxygen–carbon dioxide exchange in the lungs
Low hemoglobin levels
Impaired binding of oxygen to hemoglobin
Impaired release of oxygen from hemoglobin
Excessive hemolysis of erythrocytes due to hypersplenism or hemolytic disorders of antibody, bacterial, or
chemical origin
Certain anemias in which abnormal red blood cells are produced (e.g., hereditary spherocytosis)
Compromised blood flow to the kidneys

SECTION I—Laboratory

Tests

Threats to normal erythropoiesis occur if sufficient amounts of erythropoietin cannot be
produced or if the bone marrow is unable to
respond to erythropoietic stimulation. People without kidneys or with severe impairment of renal
function are unable to produce adequate amounts of
renal erythropoietic factor. In these individuals, the
liver is the source of erythropoietic factor. The quantity produced, however, is sufficient to maintain only
a fairly stable state of severe anemia that responds
minimally to hypoxemia.
Inadequate erythropoiesis may occur also if the
bone marrow is depressed because of drugs, toxic
chemicals, ionizing radiation, malignancies, or other
disorders such as hypothyroidism. Also, in certain
anemias and hemoglobinopathies, the bone marrow
is unable to produce sufficient normal erythrocytes.
Other substances needed for erythropoiesis are
vitamin B12, folic acid, and iron. Vitamin B12 and

TABLE 1–2

•

folic acid are required for DNA synthesis and are
needed by all cells for growth and reproduction;
because cellular reproduction occurs at such a high
rate in erythropoietic tissue, formation of RBCs is
particularly affected by a deficiency of either of these
substances. Iron is needed for hemoglobin synthesis
and normal RBC production. In addition to dietary
sources, iron from worn-out or damaged RBCs is
available for reuse in erythropoiesis.7
Leukopoiesis, the production of WBCs, maintains
a population of 5,000 to 10,000 leukocytes per cubic
millimeter of blood, with the capability for rapid
and dramatic change in response to a variety of
stimuli. No leukopoietic substance comparable to
erythropoietic factor has been identified, but many
factors are known to influence WBC production,
with a resultant excess (leukocytosis) or deficiency
(leukopenia) in leukocytes (Table 1–2).
Note that WBC levels vary in relation to diurnal

Causes of Altered Leukopoiesis

Physiological
Leukocytosis

Pathological

Pregnancy

All types of infection

Early infancy

Anemias

Emotional stress

Cushing’s disease

Strenuous exercise

Erythroblastosis fetalis

Menstruation

Leukemias

Exposure to cold

Polycythemia vera

Ultraviolet light

Transfusion reactions

Increased epinephrine secretion

Inflammatory disorders
Parasitic infestations

Leukopenia

Diurnal rhythms

Bone marrow depression
Toxic and antineoplastic drugs
Radiation
Severe infection
Viral infections
Myxedema
Lupus erythematosus and other autoimmune disorders
Peptic ulcers
Uremia
Allergies
Malignancies
Metabolic disorders
Malnutrition

CHAPTER 1—Hematology

rhythms; thus, the time at which the sample is
obtained may influence the results. Overall, leukocytes may increase by as many as 2000 cells per milliliter from morning to evening, with a corresponding
overnight decrease. Eosinophils decrease until about
noon and then rise to peak between midnight and 3
AM. This variation may be related to adrenocortical
hormone levels, which peak between 4 and 8 AM,
because an increase in these hormones can cause
circulating lymphocytes and eosinophils to disappear in a few hours.

Evaluation of Hematopoiesis
Abnormal results of studies such as a complete
blood count (CBC)) and WBC count and differential indicate the need to determine the individual’s
hematopoietic function. Evaluation of hematopoiesis begins with the examination of a bone
marrow sample and may subsequently require other
studies and a sample of peripheral blood, either
venous or capillary.
Although the collection of blood specimens is
usually the responsibility of the laboratory technician or phlebotomist, it is often the responsibility
of the nurse in emergency departments, critical

TABLE 1–3
Cell Type
Reticulocytes

Neutrophils (total)

•

and Tests of Hematopoietic Function

care units, and community and home care settings.
A detailed description of procedures for obtaining peripheral blood samples is provided in
Appendix I.

BONE MARROW EXAMINATION
Bone marrow examination (aspiration, biopsy)
requires removal of a small sample of bone marrow
by aspiration, needle biopsy, or open surgical biopsy.
Cells normally present in hematopoietic marrow
include erythrocytes and granulocytes (neutrophils,
basophils, and eosinophils) in all stages of maturation; megakaryocytes (from which platelets
develop); small numbers of lymphocytes; and occasional plasma cells (Fig. 1–2). Nucleated WBCs in
the bone marrow normally outnumber nucleated
(immature) RBCs by about 3:1. This is called the
myeloid-to-erythroid (M:E) ratio.8 Causes of
increased and decreased values on bone marrow
examination are presented in Table 1–3.
Various stains followed by microscopic examination can be performed on bone marrow aspirate to
diagnose and differentiate among the different
types of leukemia. A Sudan B stain differentiates
between acute granulocytic and lymphocytic

Causes of Alterations in Bone Marrow Cells
Increased Values

Decreased Values

Compensated RBC loss

Aplastic crisis of sickle cell disease or hereditary
spherocytosis

Response to vitamin B12 therapy

Aplastic anemia

Myeloid (chronic) leukemias

Leukemias (monocytic and lymphoblastic)

Acute myeloblastic leukemia
Lymphocytes

Lymphatic leukemia
Lymphosarcoma
Lymphomas
Mononucleosis
Aplastic anemia

Plasma cells

Myeloma

Normoblasts

Polycythemia vera

Deficiency of folic acid or vitamin B12
Aplastic anemia
Hemolytic anemia

Eosinophils

Bone marrow carcinoma
Lymphadenoma
Myeloid leukemia

SECTION I—Laboratory

Tests

leukemia. A periodic acid–Schiff stain assists in
the diagnosis of acute lymphocytic leukemia and
erythroleukemia. A terminal deoxynucleotidyl
transferase test differentiates between lymphoblastic
leukemia and lymphoma.9
Because bone marrow examination involves an
invasive procedure with risks of infection, trauma,
and bleeding, a signed consent is required.
INDICATIONS FOR BONE MARROW
EXAMINATION

Evaluation of abnormal results of CBC (e.g.,
anemia), of WBC count with differential (e.g.,
increased numbers of leukocyte precursors), or of
both tests
Monitoring of effects of exposure to bone marrow
depressants

Monitoring of bone marrow response to antineoplastic or radiation therapy for malignancies
Evaluation of hepatomegaly (enlarged liver) or
splenomegaly (enlarged spleen)
Identification of bone marrow hyperplasia or
hypoplasia, although the study may not indicate
the cause of the quantitative abnormality
Determination of marrow differential (proportion of the various types of cells present in the
marrow) and M:E ratio
Diagnosis of various disorders associated with
abnormal hematopoiesis:
Multiple myeloma
Most leukemias, both acute and chronic
Disseminated infections (granulomatous,
bacterial, fungal)
Lipid or glycogen storage diseases

Reference Values
Cell Type (%)

Adults

Infants

Children

0–1.0

—

0.5–2.5

—

56.5

32.4

57.1

Myeloblasts

0.3–5.0

0.62

1.2

Promyelocytes

1.4–8.0

0.76

1.4

Myelocytes

4.2–15.0

2.5

18.4

Neutrophilic

5.0–19.0

—

Eosinophilic

0.5–3.0

—

0–0.5

—

Bands (stabs)

13.0–34.0

14.1

Lymphocytes

14.0–16.0

49.0

16.0

Monocytes

0.3–6.0

—

Plasma cells

0.3–3.9

0.02

0.4

Megakaryocytes

0.1–3.0

0.05

0.1

2.3–3.5:1

4.4:1

2.9:1

0.2–1.3

0.1

0.5

25.6

8.0

23.1

Basophilic

1.4–4.0

0.34

1.7

Polychromatophilic

6.0–29.0

6.9

18.2

Orthochromic

1.0–4.6

0.54

2.7

Eosinophils

0.5–3.0

2.6

3.6

0–0.2

0.07

0.06

Undifferentiated
Reticulocytes
Neutrophils (total)

Basophilic

M:E ratio
Pronormoblasts
Normoblasts

Basophils

Note: There may be differences in normal values among individuals and in values obtained by different laboratory techniques.

CHAPTER 1—Hematology

Hypoplastic anemia (which may be caused by
chronic infection, hypothyroidism, chronic
renal failure, advanced liver disease, and a
number of “idiopathic” conditions)
Erythropoietic hyperplasia (which may be
caused by iron deficiency, thalassemias, hemoglobinopathies, disorders of folate and vitamin
B12 metabolism, hypersplenism, glucose-6phosphate dehydrogenase [G-6-PD] deficiency,
hereditary spherocytosis, and antibody-mediated bacterial or chemical hemolysis)
Lupus erythematosus
Porphyria erythropoietica
Parasitic infestations
Amyloidosis
Polycythemia vera
Aplastic anemia (which may be caused by drug
toxicity, idiopathic marrow failure, or infection)
CONTRAINDICATIONS

Known coagulation defects, although the test may
be performed if the importance of the information to be obtained outweighs the risks involved
in carrying out the test
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The purpose of the study
That it will be done at the bedside by a physician
and requires about 20 minutes
The general procedure, including the sensations
to be expected (momentary pain as the skin is
injected with local anesthetic and again as the
needle penetrates the periosteum, the “pulling”
sensation as the specimen is withdrawn)
That discomfort will be minimized with local
anesthetics or systemic analgesics
That the site may remain tender for several weeks
Ensure that a signed consent has been obtained.
Then:
Take and record vital signs.
Provide a hospital gown if necessary to provide
access to the biopsy site or to prevent soiling of
the client’s clothes with the solution used for skin
preparation.
Administer premedication prescribed for pain or
anxiety.

and Tests of Hematopoietic Function

preferred. In adults, the sternum or iliac crests are
the preferred sites.
The prone or side-lying position is used if the
spinous processes are the sites to be used. (These
sites are preferred if more than one specimen is to be
obtained.) The client may also be sitting, supported
by a pillow on an overbed table for a spinous process
site. The side-lying position is used if the iliac crest
or tibia is the site. For sternal punctures, the supine
position is used.
The skin is prepared with an antiseptic solution,
draped, and anesthetized, preferably with procaine,
which is painless when injected. Asepsis must be
meticulous to prevent systemic infection.
For aspiration, a large needle with stylet is
advanced into the marrow cavity. Penetration of the
periosteum is painful. The stylet is removed and a
syringe is attached to the needle. An aliquot of 0.5
mL of marrow is withdrawn. At this time, the
discomfort is a “pulling” sensation rather than pain.
The needle is removed and pressure applied to the
site. The aspirate is immediately smeared on slides
and, when dry, sprayed with a fixative.
For needle biopsy, the local anesthetic is introduced deeply enough to include the periosteum. A
special cutting biopsy needle is introduced through
a small skin incision and bored into the marrow
cavity. A core needle is introduced through the
cutting needle and a plug of marrow is removed. The
needles are withdrawn and the specimen placed in a
preservative solution. Pressure is applied to the site
for 5 to 10 minutes and a dressing applied.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to lie on the biopsied side, if
the iliac crest was entered, or supine, if the vertebral bodies were used, to maintain pressure on the
site for 10 to 15 minutes.
For sternal punctures, place the client in the
supine position or other position of comfort.
Provide bed rest for at least 30 minutes after the
procedure.
Assess puncture site every 10 to 15 minutes for
bleeding. Apply an ice bag to the puncture site to
alleviate discomfort and prevent bleeding.
Assess for infection at the site; note any redness,
swelling, or drainage.
Administer analgesics to alleviate discomfort.

THE PROCEDURE

The client is assisted to the desired position depending on the site to be used. In young children, the
most frequently chosen site is the proximal tibia; in
older children, vertebral bodies T10 to L4 are

RETICULOCYTE COUNT
Reticulocytes are immature RBCs. As RBC precursors mature (Fig. 1–2), the cell nucleus decreases in
size and eventually becomes a dense, structureless

SECTION I—Laboratory

Tests

mass.10 At the same time, the hemoglobin content of
the cell increases. Reticulocytes are cells that have
lost their nuclei but still retain fragments of mitochondria and other organelles. They also are slightly
larger than mature RBCs.11 RBCs normally enter the
circulation as reticulocytes and attain the mature
form (erythrocytes) in 1 to 2 days.
Under the stress of anemia or hypoxia, an
increased output of erythropoietin may lead to an
increased number of circulating reticulocytes (see
Table 1–1). The extent of such an increase depends
on the functional integrity of the bone marrow, the
severity and duration of anemia or hypoxia, the
adequacy of the erythropoietin response, and the
amount of available iron.12 For example, a normal
reticulocyte count in the presence of a normal
hemoglobin level indicates normal marrow activity,
whereas a normal reticulocyte count in the presence
of a low hemoglobin level indicates an inadequate
response to anemia. This may be a result of defective
erythropoietin production, bone marrow function,
or hemoglobin formation. After blood loss or effective therapy for certain kinds of anemia, an elevated
reticulocyte count (reticulocytosis) indicates that
the bone marrow is normally responsive and is
attempting to replace cells lost or destroyed.
Individuals with defects of RBC maturation and
hemoglobin production may show a low reticulocyte count (reticulocytopenia) because the cells
never mature sufficiently to enter the peripheral
circulation.
Performing a reticulocyte count involves examining a stained smear of peripheral blood to determine
the percentage of reticulocytes in relation to the
number of RBCs present.
Reference Values
Newborns

3.2% of RBCs,
declining by 2 mo

Infants

2–5%

Children

0.5–4%

Adults

0.5–2% of RBCs; can be
higher in pregnant
women

Reticulocyte index

1.0

Critical values

20% increase

INDICATIONS FOR RETICULOCYTE COUNT

Evaluation of the adequacy of bone marrow
response to stressors such as anemia or hypoxia:

A normal response is indicated by an increase
in the reticulocyte count.
Failure of the reticulocyte count to increase
may indicate depressed bone marrow functioning, defective erythropoietin production, or
defective hemoglobin production.
Evaluation of anemia of unknown etiology to
determine the type of anemia:
Elevated reticulocyte counts are found in
hemolytic anemias and sickle cell disease.
Decreased counts are seen in pernicious
anemia, thalassemia, aplastic anemia, and
severe iron-deficiency anemia.
Monitoring response to therapy for anemia:
In iron-deficiency anemia, therapeutic administration of iron should produce reticulocytosis
within 3 days and the count should remain
elevated until normal hemoglobin levels are
achieved.
Vitamin B12 therapy for pernicious anemia
should cause a prompt, continuing reticulocytosis.
Monitoring physiologic response to blood loss:
After a single hemorrhagic episode, reticulocytosis should begin within 24 to 48 hours and
peak in 4 to 7 days.
Persistent reticulocytosis or a second rise in the
count indicates continuing blood loss.
Confirmation of aplastic crisis in clients with
known aplastic anemia as evidenced by a drop in
the usually high level of reticulocytes, indicating
that RBC production has stopped despite continuing RBC destruction13
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

If the client is an adult, a venipuncture is performed
and the sample is collected in a lavender-topped
tube. A capillary sample may be obtained in infants
and children as well as in adults for whom venipuncture may not be feasible.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Abnormal values: Note and report fatigue, weakness, and color changes associated with a decrease
in counts and pain, and changes in mental state
and visual perception associated with an increase
in counts. Increased counts in 4 to 7 days indicate

CHAPTER 1—Hematology

that the therapy to treat loss of RBCs is effective,
whereas decreased counts indicate an ineffective
production of RBCs, and further testing and evaluation are needed to determine the cause. Assess
for continuing blood loss (pulse, blood pressure,
skin color, weakness, dizziness).
Critical values: Polycythemia with reticulocyte
increases of greater than 20 percent requires
immediate communication to the physician.
Prepare the client for possible phlebotomy to
reduce volume of blood and intravenous fluids
to reduce viscosity of blood. Administer
ordered myelosuppressive drugs.

IRON STUDIES
Iron plays a principal role in erythropoiesis, because
it is necessary for proliferation and maturation of
RBCs and for hemoglobin synthesis. Of the body’s
normal 4 g of iron (somewhat less in women), about
65 percent resides in hemoglobin and about 3
percent in myoglobin. A tiny but vital amount of
iron is found in cellular enzymes, which catalyze the
oxidation and reduction of iron. The remainder is
stored in the liver, bone marrow, and spleen as
ferritin or hemosiderin.14
Except for blood transfusions, the only way iron
enters the body is orally. Normally, only about 10
percent of ingested iron is absorbed, but up to 20
percent or more can be absorbed in cases of irondeficiency anemia. The body is never able to absorb
all ingested iron, no matter how great its need for
iron. In addition to dietary sources, iron from wornout or damaged RBCs is available for reuse in
erythropoiesis.15
SERUM IRON, TRANSFERRIN, AND TOTAL
IRON-BINDING CAPACITY

Any iron present in the serum is in transit among the
alimentary tract, bone marrow, and available ironstorage forms. Iron travels in the bloodstream
bound to transferrin, a protein (-globulin) manufactured by the liver. Unbound iron is highly toxic to
the body, but generally much more transferrin is
available than that needed for iron transport.
Usually, transferrin is only 30 to 35 percent saturated, with a normal range of 20 to 55 percent. If
excess transferrin is available in relation to body
iron, the percentage saturation is low. Conversely, in
situations of iron excess, both serum iron and
percentage saturation are high.
Measurement of serum iron is accomplished by
using a specific color of reagent to quantitate iron
after it is freed from transferrin. Transferrin may be
measured directly through immunoelectrophoretic

and Tests of Hematopoietic Function

techniques or indirectly by exposure of the serum to
sufficient excess iron such that all the transferrin
present can combine with the added iron. The latter
result is expressed as total iron-binding capacity
(TIBC). The percentage saturation is calculated by
dividing the serum iron value by the TIBC value.
FERRITIN

Iron is stored in the body as ferritin or hemosiderin.
Many individuals who are not anemic and who can
adequately synthesize hemoglobin may still have
decreased iron stores. For example, menstruating
women, especially those who have borne children,
usually have less storage iron. In contrast, persons
with disorders of excess iron storage such as
hemochromatosis or hemosiderosis have extremely
high serum ferritin levels.16
Serum ferritin levels are used to measure ironstorage status and are obtained by either radioimmunoassay or enzyme-linked immunoassay. The
amount of ferritin in the circulation usually is
proportional to the amount of storage iron (ferritin
and hemosiderin) in body tissues. Note that serum
ferritin levels vary according to age and gender (Fig.
1–3).
INDICATIONS FOR IRON STUDIES

Anemia of unknown etiology to determine cause
and type of anemia:
Decreased serum iron with increased transferrin levels is seen in iron-deficiency anemia and
blood loss.
Decreased serum iron and decreased transferrin levels may be seen in disorders involving
diminished protein synthesis or defects in
iron absorption (e.g., chronic diseases,
infections, widespread malignancy, malabsorption syndromes, malnutrition, nephrotic
syndrome). Percentage saturation of transferrin

Figure 1–3. Serum ferritin levels according to sex and
age. (From Hillman, RS, and Finch, CA: Red Cell
Manual, ed 7. FA Davis, Philadelphia, 1996, p 64, with
permission.)

SECTION I—Laboratory

Tests

Reference Values
Conventional Units

SI Units

Serum Iron
Newborns

350–500 mg/dL

62.7–89.5 mmol/L

Children

40–200 mg/dL

7.2–35.8 mmol/L

Men

60–170 mg/dL

10.7–30.4 mmol/L

Women

50–130 mg/dL

9.0–23.3 mmol/L

Elderly persons

40–80 mg/dL

7.2–14.3 mmol/L

Newborns

60–170 mg/dL

0.6–1.7 g/L

Adults

250–450 mg/dL

2.5–4.5 g/L

Newborns

65% saturation

0.65

Adults

20–55% saturation

0.20–0.55

Children

100–350 mg/dL

18–63 mmol/L

Adults

300–360 mg/dL

54–64 mmol/L

Elderly persons

200–310 mg/dL

36–56 mmol/L

20–40 mg/dL

20–40 mg/L

Men

50–200 mg/dL

50–200 mg/L

(average 100 mg/dL)

(avg 100 mg/L)

Women (menstruating)

12–100 mg/dL

(average 30 mg/dL)

(avg 30 mg/L)

Adults

Transferrin

% Saturation (of Transferrin)

TIBC

Ferritin
Children
Adults

may be normal if serum iron and transferrin
levels are proportionately decreased; if the
problem is solely one of protein homeostasis
(with normal iron stores), percentage saturation will be high.
Support for diagnosing hemochromatosis or
other disorders of iron metabolism and storage:
Serum iron and ferritin levels may be elevated
in hemochromatosis and hemosiderosis;
percentage saturation of transferrin is elevated,
whereas TIBC is decreased.
Serum iron levels can be elevated in lead
poisoning, after multiple blood transfusions,
and in severe hemolytic disorders that cause
release of iron from damaged RBCs.

12–100 mg/L

Monitoring hematologic responses during pregnancy, when serum iron is usually decreased,
transferrin levels are increased (in the third
trimester), percentage saturation is low, TIBC
may be increased, and ferritin may be decreased
(Note: Transferrin levels may be increased in
women taking oral contraceptives, whereas
ferritin levels may be decreased in women
who are menstruating or who have borne children.)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).

CHAPTER 1—Hematology

and Tests of Hematopoietic Function

Reference Values
Conventional Units

SI Units

Vitamin B12

Serum

200–900 pg/mL

148–664 pmol/L

Folic acid

Serum

1.8–9 ng/mL

4–20 nmol/L

RBCs

95–500 ng/mL

215–1133 nmol/L

Blood for serum iron and TIBC should be drawn
in the morning, in the fasting state, and 24 hours
or more after discontinuing iron-containing
medications.17
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. A capillary sample
may be obtained in infants and children as well
as in adults for whom venipuncture may not be
feasible.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Food, fluids, and medications withheld before
the test may be resumed after the sample is
obtained.
Complications and precautions: Note and report
signs and symptoms of anemia: decreases in test
levels, fatigue and weakness, increased pulse, exertional dyspnea, and dizziness. If anemia is caused
by blood loss, prepare to administer a transfusion
of blood products. If anemia is caused by iron
deficiency, administer ordered oral or parenteral
(intramuscular) iron supplement and instruct
client in dietary inclusion of foods high in iron
content. After 4 to 7 days, check iron studies,
RBC count, reticulocyte count, and hemoglobin
levels to see whether iron stores have been replenished.

VITAMIN B12 AND FOLIC ACID STUDIES
Vitamin B12 (cyanocobalamin) and folic acid
(pteroylglutamic acid) are essential for the production and maturation of erythrocytes. Both must be
present for normal DNA replication and cell division. In humans, vitamin B12 is obtained only by
eating animal proteins, milk, and eggs, which places
strict vegetarians at risk for developing cobalamin
deficiency; hydrochloric acid (HCl) and intrinsic
factor are required for absorption. Folic acid (or
folate) is present in liver and in many foods of

vegetable origin such as lima beans, kidney beans,
and dark-green leafy vegetables. Note that canning
and prolonged cooking destroy folate. Normally
functioning intestinal mucosa is necessary for
absorption of both vitamin B12 and folic acid.
Vitamin B12 is normally stored in the liver in
sufficient quantity to withstand 1 year of zero intake.
In contrast, most of the folic acid absorbed goes
directly to the tissues, with a smaller amount stored
in the liver. Folate stores are adequate for only 2 to 4
months.
INDICATIONS FOR VITAMIN B12 AND
FOLIC ACID STUDIES

Determination of the cause of megaloblastic
anemia:
Diagnosis of pernicious anemia, a megaloblastic anemia characterized by vitamin B12 deficiency despite normal dietary intake
Diagnosis of megaloblastic anemia caused by
deficient folic acid intake or increased folate
requirements (e.g., in pregnancy and hemolytic
anemias) or both, as indicated by decreased
serum levels of folic acid
Monitoring response to disorders that may lead to
vitamin B12 deficiency (e.g., gastric surgery, agerelated atrophy of the gastric mucosa, surgical
resection of the ileum, intestinal parasites, overgrowth of intestinal bacteria)
Monitoring response to disorders that may lead to
folate deficiency (e.g., disease of the small intestine, sprue, cirrhosis, chronic alcoholism, uremia,
some malignancies)18
Monitoring effects of drugs that are folic acid
antagonists (e.g., alcohol, anticonvulsants, antimalarials, and certain drugs used to treat
leukemia)19
Monitoring effects of prolonged parenteral nutrition
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).

SECTION I—Laboratory

Tests

Samples should be drawn after the client has
fasted for 8 hours and before injections of vitamin
B12 have been given.
Alcohol also should be avoided for 24 hours
before the test.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. A capillary sample
may be obtained in infants and children as well as in
adults for whom venipuncture may not be feasible.

The difference between men and women results
partly from menstrual blood loss in women and
partly from the effects of androgens in men.
Castration of men usually causes hemoglobin and
hematocrit to decline to nearly the same levels as
those of women. Note that a decline in erythrocytes
is experienced by both genders in old age.21
More detailed discussions of the RBC and WBC
components of the CBC are included in succeeding
sections of this chapter. Platelets are discussed in
Chapter 2.

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Foods and drugs withheld before the test may be
resumed after the sample is obtained.
Complications and precautions (anemia): Note
and report folic acid levels of less than 4 ng and a
normal level of vitamin B12, indicating folic acid
anemia. Prepare to administer ordered oral
replacement therapy of folic acid; dosage and
duration depend on the cause of the deficiency.
Perform nursing activities for vitamin B12 deficiency as in pernicious anemia diagnosed by the
Schilling test (see Chapter 20).

COMPLETE BLOOD COUNT
A CBC includes (1) enumeration of the cellular
elements of the blood, (2) evaluation of RBC
indices, and (3) determination of cell morphology
by means of stained smears. Counting is performed
by automated electronic devices capable of rapid
analysis of blood samples with a measurement error
of less than 2 percent.20
Reference values for the CBC vary across the life
cycle and between the genders. In the neonate, when
oxygen demand is high, the number of erythrocytes
also is high. As demand decreases, destruction of the
excess cells results in decreased erythrocyte, hemoglobin, and hematocrit levels. During childhood,
RBC levels again rise, although hemoglobin levels
may decrease slightly.
In prepubertal children, normal erythrocyte and
hemoglobin levels are the same for boys and girls.
During puberty, however, values for boys rise,
whereas values for girls decrease. In men, these
higher values persist to age 40 or 50, decline slowly
to age 70, and then decrease rapidly thereafter. In
women, the drop in hemoglobin and hematocrit
that begins with puberty reverses at about age 50 but
never rises to prepubertal levels or to that of men of
the same age.

Reference Values
The components of the CBC and their
reference values across the life cycle are shown in
Table 1–4.

INDICATIONS FOR A COMPLETE BLOOD COUNT

Because the CBC provides much information about
the overall health of the individual, it is an essential
component of a complete physical examination,
especially when performed on admission to a
health-care facility or before surgery. Other indications for a CBC are as follows:
Suspected hematologic disorder, neoplasm, or
immunologic abnormality
History of hereditary hematologic abnormality
Suspected infection (local or systemic, acute or
chronic)
Monitoring effects of physical or emotional stress
Monitoring desired responses to drug therapy and
undesired reactions to drugs that may cause blood
dyscrasias (Table 1–5)
Monitoring progression of nonhematologic
disorders such as chronic obstructive pulmonary
disease, malabsorption syndromes, malignancies,
and renal disease
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a lavender-topped tube. A capillary
sample may be obtained in infants and children, as
well as in adults for whom venipuncture may not be
feasible.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the

TABLE 1–4

•

Reference Values for Complete Blood Count
Adult

CBC Component
Red blood cells
(RBCs)

Newborn

1 Mo

4.8–7.1 million/mm3
4.8–7.1 10 /L (SI units)
12

6 Mo

1–10 Yr

Male

Female

4.1–6.4
million/mm3

3.8–5.5
million/mm3

4.5–4.8
million/mm3

4.6–6.2
million/mm3

4.2–5.4 million/mm3

35–49%

30–40%

35–41%

40–54%

38–47%

Hemoglobin (Hgb)

14–24 g/L (SI units)

11–20 g/dL

10–15 g/dL

11–16 g/dL

13.5–18 g/dL

12–16 g/dL

140–240 g/L (SI units)

110–200 g/L

100–150 g/L

110–160 g/L

135–180 g/L

120–160 g/L

96–108 m3

82–91 3

—

80–94 m3

81–99 m3

96–108 fL (SI units)

82–91 fL

—

80–94 fL

81–99 fL

32–34 pg

27–31 pg

—

27–31 pg

32–33%

32–36%

—

32–36%

320–330 S/L (SI units)

320–360 S/L

RBC indices
MCV*

†

MCH

MCHC

‡

Stained RBC
examination
White blood cells
(WBCs)

320–360 S/L
Normochromic and normocytic for all age groups and both sexes (see p. 23)

9,000–30,000/mm3

6,000–18,000/mm3

6,000–16,000/mm3

5,000–13,000/mm3

5,000–10,000/mm3

9,000–30,000 10 /L (SI
units)
9

(Continued on following page)

and Tests of Hematopoietic Function

4.4–64%

CHAPTER 1—Hematology

Hematocrit (Hct)

•

Reference Values for Complete Blood Count (Continued)
Adult

CBC Component

Newborn

1 Mo

6 Mo

1–10 Yr

Male

Female

Neutrophils

45% by 1 wk

40% by 4 wk

32%

60% after age 2 yr

—

54–75%
(3000–7500/mm3)

Bands

—

3–8% (150–700/mm3)

Eosinophils

—

0–3%

—

1–4% (50–400/mm3)

Basophils

—

1–3%

—

0–1% (25–100/mm3)

Monocytes

—

4–9%

—

2–8% (100–500/mm3)

Lymphocytes

41% by 1 wk

56% by 4 wk

61%

59% after age 2 yr

—

25–40%
(1500–4500/mm3)

T lymphocytes

—

60–80% of lymphocytes

B lymphocytes

—

Platelets

140,000–300,000/mm3

150,000–390,000/
mm3

200,000–473,000/
mm3

150,000–450,000/
mm3

150,000–450,000/mm3

140–300 109/L (SI units)

150–390 109/L

200–473 109/L

150–450 109/L

* Mean corpuscular volume.
†
Mean corpuscular hemoglobin.
‡
Mean corpuscular hemoglobin concentration.

10–20% of lymphocytes

Tests

Differential WBC

SECTION I—Laboratory

TABLE 1–4

CHAPTER 1—Hematology

TABLE 1–5

•

and Tests of Hematopoietic Function

Drugs That May Cause Blood Dyscrasias

Generic Name or Class

Trade Names

Acetaminophen and acetaminophen
compounds

Bancap, Capital, Colrex, Comtrex, Darvocet-N, Datril, Dolene,
Duradrin, Duradyne, Esgic, Excedrin, Liquiprin, Midrin,
Neopap Supprettes, NyQuil, Ornex, Panadol, Parafon Forte,
Percogesic, Phrenilin, Sedapap, Sinarest, Sinutab, Supac,
Tylenol, Tempra, Tylenol with Codeine, Valadol, Vanquish,
Wygesic

Acetophenazine maleate

Tindal

Aminosalicylic acid

Pamisyl, PAS, Rezipas

Amphotericin B

Fungizone, Mysteclin F

Antineoplastic agents
Arsenicals
Carbamazepine

Tegretol

Chloramphenicol

Chloromycetin

Chloroquine

Aralen

Ethosuximide (methsuximide, phensuximide)

Zarontin

Furazolidone

Furoxone

Haloperidol

Haldol

Hydantoin derivatives
Ethotoin

Peganone

Mephenytoin

Mesantoin

Phenytoin

Dilantin, Diphenylan

Hydralazine

Apresazide, Apresoline, Bolazine, Ser-Ap-Es, Serpasil-Apresoline

Hydroxychloroquine sulfate

Plaquenil

Indomethacin

Indocin

Isoniazid

INH, Nydrazid, Rifamate

MAO inhibitors

Eutonyl, Nardil, Parnate

Mefenamic acid

Ponstel

Mepacrine

Atabrine

Mephenoxalone

Lenetron

Mercurial diuretics

Thiomerin

Metaxalone

Skelaxin

Methaqualone

Quaalude, Sopor

Methyldopa

Aldoclor, Aldomet, Aldoril

Nitrites
Nitrofurantoin

Cyantin, Furadantin, Macrodantin

Novobiocin

Albamycin

Oleandomycin

Matromycin
(Continued on following page)

SECTION I—Laboratory

TABLE 1–5

•

Tests

Drugs That May Cause Blood Dyscrasias (Continued)

Generic Name or Class

Trade Names

Oxyphenbutazone

Oxalid, Tandearil

Paramethadione

Paradione

Penicillamine

Cuprimine, Depen

Penicillins
Phenacemide

Phenurone

Phenobarbital
Phenylbutazone

Azolid, Butazolidin

Phytonadione

AquaMEPHYTON, Konakion

Primaquine
Primidone

Mysoline

Pyrazolone derivatives

Butazolidin, Tandearil, Oxalid

Pyrimethamine

Daraprim

Rifampin

Rifadin, Rifamate, Rimactane

Radioisotopes
Spectinomycin

Trobicin

Sulfonamides
Mafenide

Sulfamylon cream

Phthalylsulfathiazole

Sulfathalidine

Sulfabenzamide

Sultrin vaginal cream

Sulfacetamide

Bleph-10, Cetamide ointment, Isopto Cetamide, Sulamyd, Sultrin
vaginal cream

Sulfachloropyridazine

Sonilyn

Sulfacytine

Renoquid

Sulfadiazine

Silvadene

Sulfameter

Sulla

Sulfamethiozole

Thiosulfil Forte

Sulfamethoxazole

Azo Gantanol, Bactrim, Gantanol, Septra

Sulfamethoxypyridazine

Midicel

Sulfanilamide

AVC vaginal cream

Sulfasalazine

Azulfidine

Sulfathiazole

Sultrin vaginal cream, Triple Sulfa cream

Sulfinpyrazone

Anturane

Sulfisoxazole

Azo Gantrisin, Gantrisin

Sulfones
Dapsone
DDS
Sulfoxone

CHAPTER 1—Hematology

TABLE 1–5

•

and Tests of Hematopoietic Function

Drugs That May Cause Blood Dyscrasias

Generic Name or Class

Trade Names

Sulfonylureas
Acetohexamide

Dymelor

Chlorpropamide

Diabinese

Tolazamide

Tolinase

Tolbutamide

Orinase

Tetracyclines

Achromycin

Chlortetracycline

Aureomycin

Demeclocycline

Declomycin

Doxycycline

Doxychel, Doxy, Vibramycin, Vibra-Tabs

Meclocycline

Meclan

Methacycline

Rondomycin

Minocycline

Minocin

Oxytetracycline

Oxlopar, Terramycin

Thiazide diuretics (rare hematologic
side effects)

Ademol, Diuril, Enduron, Exna, Naturetin, Naqua, Renese,
Saluron

Thiocyanates
Trimethadione

Tridione

Tripelennamine

Pyribenzamine, PBZ

Troleandomycin

Cyclamycin, Tao capsules and suspension

Valproic acid
Valproate
Vitamin A

Aquasol A, Alphalin

same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Abnormal range of values: Note and report
decreases in individual or entire CBC (pancytopenia) panel. Prepare to administer drugs and treatments, or both, that have been ordered to manage
anemia (RBC, hematocrit [Hct], hemoglobin
[Hgb], RBC indices), clotting process (platelet),
or infectious process (WBC, differential).

ERYTHROCYTE STUDIES
The mature RBC (erythrocyte) is a biconcave disk
with an average life span of 120 days. Because it lacks
a nucleus and mitochondria, it is unable to synthesize protein, and its limited metabolism is barely
enough to sustain it. Erythrocytes function primarily as containers for Hgb. As such, they transport

oxygen from the lungs to all body cells and transfer
carbon dioxide from the cells to the organs of excretion. The RBC is resilient and capable of extreme
changes in shape. It is admirably designed to survive
its many trips through the circulation.22
Old, damaged, and abnormal erythrocytes are
removed mainly by the spleen and also by the liver
and the red bone marrow. The iron is returned to
plasma transferrin and is transported back to the
erythroid marrow or stored within the liver and
spleen as ferritin and hemosiderin. The bilirubin
component of Hgb is carried by plasma albumin to
the liver, where it is conjugated and excreted into the
bile. Most of this conjugated bilirubin is ultimately
excreted in the stool, although some appears in the
urine or is returned to bile.
The hematologist determines the numbers, structure, color, size, and shape of erythrocytes; the types

SECTION I—Laboratory

Tests

and amount of Hgb they contain; their fragility; and
any abnormal components.

INDICATIONS FOR AN ERYTHROCYTE (RBC)
COUNT

Routine screening as part of a CBC
Suspected hematologic disorder involving RBC
destruction (e.g., hemolytic anemia)
Monitoring effects of acute or chronic blood loss
Monitoring response to drug therapy that may
alter the RBC count (see Table 1–5)
Monitoring clients with disorders associated with
elevated RBC counts (e.g., polycythemia vera,
chronic obstructive pulmonary disease)
Monitoring clients with disorders associated with
decreased RBC counts (e.g., malabsorption
syndromes, malnutrition, liver disease, renal
disease, hypothyroidism, adrenal dysfunction,
bone marrow failure)

ERYTHROCYTE (RBC) COUNT
The erythrocyte (RBC) count, a component of the
CBC, is the determination of the number of RBCs
per cubic millimeter. In international units, this is
expressed as the number of RBCs per liter of blood.
The test is less significant by itself than it is in
computing Hgb, Hct, and RBC indices.
Many factors influence the level of circulating
erythrocytes. Decreased numbers are seen in disorders involving impaired erythropoiesis excessive
blood cell destruction (e.g., hemolytic anemia), and
blood loss, and in chronic inflammatory diseases. A
relative decrease also may be seen in situations with
increased body fluid in the presence of a normal
number of RBCs (e.g., pregnancy). Increases in the
RBC count are most commonly seen in polycythemia vera, chronic pulmonary disease with
hypoxia and secondary polycythemia, and dehydration with hemoconcentration. Excessive exercise,
anxiety, and pain also produce higher RBC counts.
Many drugs can cause a decrease in circulating RBCs
(see Table 1–5), whereas a few drugs, such as methyldopa and gentamicin, can cause an increase.23

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

INTERFERING FACTORS

NURSING CARE AFTER THE PROCEDURE

Excessive exercise, anxiety, pain, and dehydration
may lead to false elevations.
Hemodilution in the presence of a normal
number of RBCs may lead to false decreases (e.g.,
excessive administration of intravenous fluids,
normal pregnancy).
Many drugs may cause a decrease in circulating
RBCs (see Table 1–5).
Drugs such as methyldopa and gentamicin may
cause an elevated RBC count.

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Anemia: Note and report signs and symptoms of
anemia associated with decreased counts in
combination with Hgb and Hct decreases. Prepare
to administer ordered oral or parenteral iron
preparation or a transfusion of whole blood or
packed RBCs. Prepare for phlebotomy if levels are

Reference Values
Conventional Units

SI Units

Newborns

4.8–7.1 million/mm

4.8–7.1 1012/L

1 mo

4.1–6.4 million/mm3

4.1–6.4 1012/L

6 mo

3.8–5.5 million/mm3

3.8–5.5 1012/L

1–10 yr

4.5–4.8 million/mm3

4.5–4.8 1012/L

Men

4.6–6.2 million/mm3

4.6–6.2 1012/L

Women

4.2–5.4 million/mm3

4.2–5.4 1012/L

Adults

CHAPTER 1—Hematology

increased in polycythemia vera or secondary polycythemia.

HEMATOCRIT
Blood consists of a fluid portion (plasma) and a
solid portion that includes RBCs, WBCs, and
platelets. More than 99 percent of the total blood cell
mass is composed of RBCs. The Hct or packed RBC
volume measures the proportion of RBCs in a
volume of whole blood and is expressed as a
percentage.
Several methods can be used to perform the test.
In the classic method, anticoagulated venous blood
is pipetted into a tube 100 mm long and then
centrifuged for 30 minutes so that the plasma and
blood cells separate. The volumes of packed RBCs
and plasma are read directly from the millimeter
marks along the side of the tube. In the micro
method, venous or capillary blood is used to fill a
small capillary tube, which is then centrifuged for 4
to 5 minutes. The proportions of plasma and RBCs
are determined by means of a calibrated reading
device. Both techniques allow visual estimation of
the volume of WBCs and platelets.24
With the newer, automated methods of cell
counting, the Hct is calculated indirectly as the
product of the RBC count and mean cell volume.
Although this method is generally quite accurate,
certain clinical situations may cause errors in interpreting the Hct. Abnormalities in RBC size and
extremely elevated WBC counts may produce false
Hct values. Elevated blood glucose and sodium may
produce elevated Hct values because of the resultant
swelling of the erythrocyte.25
Normally, the Hct parallels the RBC count. Thus,
factors influencing the RBC count also affect the
results of the Hct.
Reference Values
Conventional Units

SI Units

Newborns

44–64%

0.44–64

1 mo

35–49%

0.35–0.49

6 mo

30–40%

0.30–0.40

1–10 yr

35–41%

0.35–0.41

Men

40–54%

0.40–0.54

Women

38–47%

0.38–0.47

Adults

and Tests of Hematopoietic Function

INTERFERING FACTORS

Abnormalities in RBC size and extremely elevated
WBC counts may alter Hct values.
Elevated blood glucose and sodium may produce
elevated Hct values because of swelling of the
erythrocyte.
Factors that alter the RBC count such as hemodilution and dehydration also influence the Hct.
INDICATIONS FOR A HEMATOCRIT TEST

Routine screening as part of a CBC
Along with an Hgb (i.e., an “H and H”), to monitor blood loss and response to blood replacement
Along with an Hgb, to evaluate known or
suspected anemia and related treatment
Along with an Hgb, to monitor hematologic
status during pregnancy
Monitoring responses to fluid imbalances or to
therapy for fluid imbalances:
A decreased Hct may indicate hemodilution.
An increased Hct may indicate dehydration.
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

The volume of the sample needed depends on the
method used to determine the Hct. With the exception of the classic method of Hct determination, a
capillary sample is usually sufficient to perform the
test. If a venipuncture is performed, the sample is
collected in a lavender-topped tube.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Critical values: Notify the physician at once if
the Hct is greater than 60 percent or less than
14 percent. Prepare the client for possible
transfusion of blood products or infusion of
intravenous fluids and for further procedures
to evaluate the cause or source of the blood
loss or hemoconcentration.

HEMOGLOBIN

Critical values 14% or 60%

0.14–0.60

Note: Values vary across the life cycle and between genders.

Hemoglobin is the main intracellular protein of the
RBC. Its primary function is to transport oxygen to
the cells and to remove carbon dioxide from them
for excretion by the lungs. The Hgb molecule
consists of two main components: heme and globin.

SECTION I—Laboratory

Tests

Heme is composed of the red pigment porphyrin
and iron, which is capable of combining loosely with
oxygen. Globin is a protein that consists of nearly
600 amino acids organized into four polypeptide
chains. Each chain of globin is associated with a
heme group.
Each RBC contains approximately 250 million
molecules of hemoglobin, with some erythrocytes containing more hemoglobin than others.
The oxygen-binding, -carrying, and -releasing
capacity of Hgb depends on the ability of the
globin chains to shift position normally during the
oxygenation–deoxygenation process. Structurally
abnormal chains that are unable to shift normally
have decreased oxygen-carrying ability. This
decreased oxygen transport capacity is characteristic
of anemia.
Hemoglobin also functions as a buffer in the
maintenance of acid–base balance. During transport, carbon dioxide (CO2) reacts with water (H2O)
to form carbonic acid (H2CO3). This reaction is
speeded by carbonic anhydrase, an enzyme
contained in RBCs. The carbonic acid rapidly dissociates to form hydrogen ions (H) and bicarbonate
ions (HCO3–). The hydrogen ions combine with the
Hgb molecule, thus preventing a buildup of hydrogen ions in the blood. The bicarbonate ions diffuse
into the plasma and play a role in the bicarbonate
buffer system. As bicarbonate ions enter the bloodstream, chloride ions (Cl) are repelled and move
back into the erythrocyte. This “chloride shift”
maintains the electrical balance between RBCs and
plasma.26
Hemoglobin determinations are of greatest use in
the evaluation of anemia, because the oxygen-carrying capacity of the blood is directly related to the
Hgb level rather than to the number of erythrocytes.
To interpret results accurately, the Hgb level must be
determined in combination with the Hct level.
Normally, Hgb and Hct levels parallel each other and
are commonly used together to express the degree of
anemia. The combined values are also useful in evaluating situations involving blood loss and related
treatment. The Hct level is normally three times the
Hgb level. If erythrocytes are abnormal in shape or
size or if Hgb manufacture is defective, the relationship between Hgb and Hct is disproportionate.27,28

Reference Values
Conventional Units

SI Units

Newborns

14–24 g/dL

140–240 g/L

1 mo

11–20 g/dL

110–200 g/L

6 mo

10–15 g/dL

100–150 g/L

1–10 yr

11–16 g/dL

110–160 g/L

13.5–18 g/dL

135–180 g/L

12–16 g/dL

120–160 g/L

6.0 g/dL
200 g/dL

60 g/L
200 g/L

Adults
Men
Women
Critical values

Note: Ratio of hemoglobin to hematocrit

3:1.

ate known or suspected anemia and related treatment
Along with an Hct, to monitor blood loss and
response to blood replacement
Along with an Hct, to monitor hematologic status
during pregnancy
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Critical values: Notify the physician at once if
the Hgb is less than 6.0 g/dL. Prepare the client
for possible transfusion of blood products and
for further procedures to evaluate cause or
source of blood loss.

INTERFERING FACTORS

Factors that alter the RBC count may also influence
Hgb levels
INDICATIONS FOR HEMOGLOBIN DETERMINATION

Routine screening as part of a CBC
Along with an Hct (i.e., an “H and H”), to evalu-

RED BLOOD CELL INDICES
RBC indices are calculated mean values that reflect
the size, weight, and Hgb content of individual
erythrocytes. They consist of the mean corpuscular
volume (MCV), the mean corpuscular hemoglobin
(MCH), and the mean corpuscular hemoglobin

CHAPTER 1—Hematology

TABLE 1–6

Microcytic,
normochromic
Microcytic,
hypochromic
Macrocytic,
normochromic

Classification of Anemias
MCV*
(mm3)

MCH†
(pg)

MCHC‡
(%)

Sepsis, hemorrhage, hemolysis,
drug-induced aplastic anemia,
radiation, hereditary spherocytosis

82–92

25–30

32–36

Renal disease, infection, liver
disease, malignancies

20–25

Iron deficiency, lead poisoning,
thalassemia, rheumatoid arthritis

50–80

12–25

25–30

95–150

30–50

32–36

Anemia
Normocytic,
normochromic

•

and Tests of Hematopoietic Function

Examples of Causes

Vitamin B12 and folic acid deficiency,
some drugs, pernicious anemia

* Mean corpuscular volume.
†
Mean corpuscular hemoglobin.
‡
Mean corpuscular hemoglobin concentration.

concentration (MCHC). MCV indicates the volume
of the Hgb in each RBC, MCH is the weight of the
Hgb in each RBC, and MCHC is the proportion of
Hgb contained in each RBC. MCHC is a valuable
indicator of Hgb deficiency and of the oxygen-carrying capacity of the individual erythrocyte. A cell of
abnormal size, abnormal shape, or both may contain
an inadequate proportion of Hgb.
RBC indices are used mainly in identifying
and classifying types of anemias. Anemias are
generally classified according to RBC size and Hgb
content. Cell size is indicated by the terms normocytic, microcytic, and macrocytic. Hemoglobin
content is indicated by the terms normochromic,
hypochromic, and hyperchromic. Table 1–6 shows

anemias classified according to these terms and in
relation to the results of RBC indices.
To calculate the RBC indices, the results of an
RBC count, Hct, and Hgb are necessary. Thus,
factors that influence these three determinations
(e.g., abnormalities of RBC size or extremely
elevated WBC counts) may result in misleading RBC
indices. For this reason, a stained blood smear may
be used to compare appearance with calculated
values and to determine the etiology of identified
abnormalities.
INTERFERING FACTORS

Because RBC indices are calculated from the results
of the RBC count, Hgb, and Hct, factors that influ-

Reference Values
Men
MCV

Women

80–94 m

Newborns

81–99 m

SI Units

96–108 m

81–99 fL (women)
96–108 fL (newborns)

MCH

27–31 pg

32–34 pg

32–34 pg (women)
32–34 pg (newborns)

MCHC

32–36%

32–33%

320–360 g/L (women)
320–330 g/L (newborns)

Normal values for RBC indices are shown in Table 1–4 in relation to the CBC and also are repeated above for adults. Values in
newborn infants are slightly different, but adult levels are achieved within approximately 1 month of age.

SECTION I—Laboratory

Tests

ence the latter three tests (e.g., abnormalities of RBC
size, extremely elevated WBC counts) also influence
RBC indices.
INDICATIONS FOR RED BLOOD CELL INDICES

Routine screening as part of a CBC
Identification and classification of anemias (see
Table 1–6)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).

TABLE 1–7
Descriptive Term
Macrocytosis

•

STAINED RED BLOOD CELL
EXAMINATION
The stained RBC examination (RBC morphology)
involves examination of RBCs under a microscope.
It is usually performed to compare the actual
appearance of the cells with the calculated values
for RBC indices. Cells are examined for abnormalities in color, size, shape, and contents. The test is
performed by spreading a drop of fresh anticoagulated blood on a glass slide. The addition of stain
to the specimen is used to enhance RBC characteristics.
As with RBC indices, RBC color is described as
normochromic, hypochromic, or hyperchromic,
indicating, respectively, normal, reduced, or elevated
amounts of Hgb. Cell size may be described as
normocytic, microcytic, or macrocytic, depending
on whether cell size is normal, small, or abnormally
large, respectively. Cell shape is described using
terms such as poikilocyte, anisocyte, leptocyte, and
spherocyte (Table 1–7). The cells are examined also
for inclusions or abnormal cell contents, for example, Heinz bodies, Howell-Jolly bodies, Cabot’s rings,
and siderotic granules (Table 1–8).

Red Blood Cell Abnormalities Seen on Stained Smear
Observation

Significance

Cell diameter 8 m

Megaloblastic anemias

MCV* 95 m3

Severe liver disease
Hypothyroidism

Microcytosis

Cell diameter 6 m

Iron-deficiency anemia

MCV 80 m

Thalassemias

MCHC† 27

Anemia of chronic disease

Hypochromia

Increased zone of central pallor

Diminished Hgb content

Hyperchromia

Microcytic, hyperchromic cells

Chronic inflammation

Increased bone marrow stores of
iron

Defect in ability to use iron for Hgb synthesis

Polychromatophilia

Presence of red cells not fully
hemoglobinized

Reticulocytosis

Poikilocytosis

Variability of cell shape

Sickle cell disease

Microangiopathic hemolysis
Leukemias
Extramedullary hematopoiesis
Marrow stress of any cause

CHAPTER 1—Hematology

TABLE 1–7

•

Red Blood Cell Abnormalities Seen on Stained Smear

Descriptive Term
Anisocytosis

and Tests of Hematopoietic Function

Observation

Significance
Reticulocytosis

Variability of cell size

Transfusing normal blood into microcytic or
macrocytic cell population
Leptocytosis

Spherocytosis

Hypochromic cells with small
central zone of Hgb (“target
cells”)

Thalassemias

Cells with no central pallor,
loss of biconcave shape

Loss of membrane relative to cell volume

Obstructive jaundice

Hereditary spherocytosis
Schistocytosis

MCHC high

Accelerated red blood cell destruction by
reticuloendothelial system

Acanthocytosis

Presence of cell fragments in
circulation

Increased intravascular mechanical trauma

Echinocytosis

Irregularly spiculated surface

Microangiopathic hemolysis
Irreversibly abnormal membrane
lipid content
Liver disease
Abetalipoproteinemia
Regularly spiculated cell surface

Reversible abnormalities of membrane lipids
High plasma-free fatty acids
Bile acid abnormalities
Effects of barbiturates, salicylates, and so on

Stomatocytosis

Elongated, slitlike zone of central
pallor

Hereditary defect in membrane sodium
metabolism
Severe liver disease

Elliptocytosis

Oval cells

Hereditary anomaly, usually harmless

Source: Adapted from Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests,
ed 11. FA Davis, Philadelphia, 2000 p. 68, with permission.
* Mean corpuscular volume.
†Mean corpuscular hemoglobin concentration.

Reference Values
In a normal smear, all cells are uniform in color,
size, and shape and are free of abnormal
contents. A normal RBC may be described as a
normochromic, normocytic cell.

INDICATIONS FOR A STAINED RED BLOOD CELL
EXAMINATION

Abnormal calculated values for RBC indices

Evaluation of anemia and related disorders
involving RBCs (see Tables 1–6, 1–7, and 1–8)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a lavender-topped tube. A capillary

SECTION I—Laboratory

TABLE 1–8

•

Tests

Types of Abnormal Red Blood Cell Inclusions and Their Causes

Type (Composition)
Heinz bodies (denatured Hgb)

Causes of Inclusions
-Thalassemia
G-6-PD deficiency
Hemolytic anemias
Methemoglobinemia
Splenectomy
Drugs: analgesics, antimalarials, antipyretics, nitrofurantoin (Furadantin),
nitrofurazone (Furacin), phenylhydrazine, sulfonamides, tolbutamide,
vitamin K (large doses)

Basophilic stippling (residual
cytoplasmic RNA)

Anemia caused by liver disease
Lead poisoning
Thalassemia

Howell-Jolly bodies (fragments of residual DNA)

Splenectomy
Intense or abnormal RBC production resulting from hemolysis or inefficient erythropoiesis

Cabot’s rings (composition
unknown)

Same as for Howell-Jolly bodies

Siderotic granules (ironcontaining granules)

Abnormal iron metabolism
Abnormal hemoglobin manufacture

sample may be obtained in infants and children as
well as in adults for whom venipuncture may not be
feasible.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).

HEMOGLOBIN ELECTROPHORESIS
The Hgb molecule consists of four polypeptide
globin chains and four heme components containing iron and the red pigment porphyrin.
Hemoglobin formation is genetically determined,
and the types of globin chains normally formed are
termed alpha ( ), beta (), gamma ( ), and delta
( ). Combinations of these chains form various
types of Hgb. Disorders of synthesis and production
of globin chains result in the formation of abnormal
Hgb.
Hemoglobin electrophoresis is a technique for
identifying the types of Hgb present and for determining the percentage of each type. Exposed to an
electrical current, the several types of Hgb migrate
toward the positive pole at different rates. The
patterns created are compared with standard
patterns.

At birth, most RBCs contain fetal hemoglobin
(Hgb F), which is made up of two chains and two
chains. Within a few months, through sequential
suppression and activation of individual genes, Hgb
F largely disappears and is replaced by adult hemoglobin (Hgb A). Hgb A, composed of two chains
and two chains, makes up more than 95 percent of
Hgb in adults. A minor type of Hgb, Hgb A2, consisting of two chains and two chains, also is found
in small amounts (2 to 3 percent) in adults. Traces of
Hgb F persist throughout life (Fig. 1–4).29
More than 150 genetic abnormalities in the Hgb
molecule have been identified. These are termed
thalassemias and hemoglobinopathies. Thalassemias
are genetic disorders in globin chain synthesis that
result in decreased production rates of - or globin chains. Hemoglobinopathies refer to disorders involving an abnormal amino acid sequence in
the globin chains.
In -thalassemia, for example, production of
chains and Hgb A is decreased. The oversupply of
chains results in the formation of hemoglobin H
(Hgb H), which consists of four chains (Fig. 1–5).
Complete absence of a chain production (homozygous thalassemia A) is incompatible with life and
generally results in stillbirth during the second
trimester of pregnancy. The cord blood of such
fetuses shows high levels of hemoglobin Barts, a type

CHAPTER 1—Hematology

Figure 1–4. Changes in hemoglobin with development. (From Hillman, RS, and Finch, CA: Red Cell
Manual, ed 7. FA Davis, Philadelphia, 1996, p. 11, with
permission.)

of Hgb that evolves from unpaired
chains.
Hemoglobin Barts itself has such a high affinity for
oxygen that it releases none to the tissues.
In -thalassemia minor, a decrease is seen in chain production and, therefore, a reduction in the
amount of Hgb A formed. In -thalassemia major,
all -chain production is lost and no Hgb A is
formed. The chains are then used to form Hgb F
and Hgb A2.
Among the most common Hgb abnormalities are
the sickle cell disorders, which exhibit a double
gene defect that results in the production of hemoglobin S (Hgb S). In Hgb S, the amino acid valine is
substituted for glutamine at a critical position on the
globin chain, which causes the chains to “lock”
when deoxygenated, deforming the erythrocyte into
the sickled shape. Repeated sickling damages RBC
membranes and shortens the cells’ life spans. The
abnormally shaped cells pass more sluggishly
through the circulation, leading to impaired tissue
oxygenation.
The gene for Hgb S is most prevalent in black
populations and may be present as either sickle cell
trait (having one recessive gene for Hgb S) or sickle
cell disease (having both recessive genes for Hgb S).

and Tests of Hematopoietic Function

The Sickledex test, a screening test for sickle cell
disorders, detects sickled erythrocytes under conditions of oxygen deprivation. Hemoglobin electrophoresis is necessary, however, to differentiate
sickle cell trait (20 to 40 percent Hgb S) from sickle
cell disease (70 percent Hgb S).
Many other types of abnormal Hgb are caused by
defects in globin chain synthesis. Hemoglobin C
(Hgb C), for example, has an abnormal amino acid
substitution on the chain and can lead to a form of
mild hemolytic anemia. Other examples of abnormal Hgb resulting from rearrangement or substitution of the amino acids on the globin chains include
hemoglobin E (Hgb E), hemoglobin Lepore (chain abnormalities), and hemoglobin Constant
Spring ( -chain abnormality).30
Other disorders involving Hgb pertain to the
oxygen-combining ability of the heme portion of
the molecule. Examples of types of Hgb associated
with such disorders are methemoglobin (Hgb M),
sulfhemoglobin, and carboxyhemoglobin. Hgb M is
formed when the iron contained in the heme
portion of the Hgb molecule is oxidized to a ferric
instead of a ferrous form, thus impairing its oxygencombining ability. Methemoglobinemia may be
hereditary or acquired. The acquired form may be
caused by excessive radiation or by the toxic effects
of chemicals and drugs (e.g., nitrates, phenacetin,
lidocaine). Note that Hgb F is more easily converted
to Hgb M than is Hgb A.
Sulfhemoglobin is a pigment that results from
Hgb combining with inorganic sulfides. It occurs in
those who take sulfonamides or acetanilid.
Carboxyhemoglobin results when Hgb is exposed
to carbon monoxide. Although this type of Hgb is
most commonly seen in individuals with excessive
exposure to automobile exhaust fumes, it may also
occur in heavy smokers.31 Tests other than Hgb electrophoresis are used to determine the presence of
Hgb M and carboxyhemoglobin.
INDICATIONS FOR HEMOGLOBIN
ELECTROPHORESIS

Suspected thalassemia, especially in individuals
with positive family history for the disorder
Differentiation among the types of thalassemias
Evaluation of a positive Sickledex test to differentiate sickle cell trait (20 to 40 percent Hgb S) from
sickle cell disease (70 percent Hgb S)
Evaluation of hemolytic anemia of unknown
etiology
Diagnosis of Hgb C anemia
Identification of the numerous types of abnormal
Hgb, most of which do not produce clinical
disease

SECTION I—Laboratory

Tests

Figure 1–5. Formation of manual and abnormal hemoglobin. (From Hillman, RS, and Finch, CA: Red Cell Manual, ed
7. FA Davis, Philadelphia, 1996, with permission.)

Reference Values
The normal values shown for Hgb electrophoresis are for adults. In
newborn infants, 60 to 90 percent of Hgb may consist of Hgb F. This
amount decreases to 10 to 20 percent by 6 months of age and to 2 to
4 percent by 1 year. Abnormal forms of Hgb (e.g., Hgb S, Hgb H) are
not normally present.
Conventional Units

SI Units

Hgb A

95–97%

0.95

Hgb A2

2–3%

0.02–0.03

Hgb F

0.01

Methemoglobin
(Hgb M)

2% or 0.06–0.24 g/dL

Sulfhemoglobin

Minute amounts

Carboxyhemoglobin

0–2.3%
4–5% in smokers

CHAPTER 1—Hematology

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).

and Tests of Hematopoietic Function

The test is performed by exposing RBCs to
increasingly dilute saline solutions. The percentage
of the solution at which the cells swell and rupture is
then noted.

THE PROCEDURE

Reference Values

Normal erythrocytes rupture in saline solutions
of 0.30 to 0.45 percent. RBC rupture in solutions
of greater than 0.50 percent saline indicates
increased fragility. Lack of rupture in solutions
of less than 0.30 percent saline indicates
decreased RBC fragility.

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Complications and precautions: Note and report
signs and symptoms associated with the specific
type of anemia identified by electrophoresis.
Prepare to instruct in therapy and prevention of
complications. Offer information about genetic
factors and counseling or both, if appropriate.

INDICATIONS FOR OSMOTIC FRAGILITY TEST

Confirmation of disorders that alter RBC fragility,
including hereditary anemias (see Table 1–9)
Evaluation of the extent of extrinsic damage to
RBCs from burns, inadvertent instillation of
hypotonic intravenous fluids, microorganisms,
and excessive exercise
NURSING CARE BEFORE THE PROCEDURE

OSMOTIC FRAGILITY
The osmotic fragility test determines the ability of
the RCB membrane to resist rupturing in a hypotonic saline solution. Normal disk-shaped cells can
imbibe water and swell significantly before
membrane capacity is exceeded, but spherocytes
(RBCs that lack the normal biconcave shape) and
cells with damaged membranes burst in saline solutions only slightly less concentrated than normal
saline. Conversely, in thalassemia, sickle cell disease,
and other disorders, RBCs are more than normally
resistant to osmotic damage (Table 1–9).

TABLE 1–9

•

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a green-topped tube. A capillary sample
may be obtained in infants and children as well as in
adults for whom a venipuncture may not be feasible.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the

Causes of Altered Erythrocyte Osmotic Fragility

Decreased Fragility

Increased Fragility

Iron-deficiency anemias

Hereditary spherocytosis

Hereditary anemias (sickle cell, hemoglobin C,
thalassemias)

Hemolytic anemias

Liver diseases

Autoimmune anemias

Polycythemia vera

Burns

Splenectomy

Toxins (bacterial, chemical)

Obstructive jaundice

Hypotonic infusions
Transfusion with incompatible blood
Mechanical trauma to RBCs (prosthetic heart valves,
disseminated intravascular clotting, parasites)
Enzyme deficiencies (PK kinase, G-6-PD)

SECTION I—Laboratory

Tests

same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Abnormal test results, complications, and
precautions: Respond as for any laboratory analysis to determine RBC abnormalities leading to
anemia.

RED BLOOD CELL ENZYMES
To maintain normal shape and flexibility as well as
to combine with and release oxygen, RBCs must
generate energy. The needed energy is produced
almost exclusively through the breakdown of
glucose, a process that is catalyzed by a number of
enzymes. Deficiencies of these enzymes are associated with hemolytic anemia. Two of the most
common deficiencies, both hereditary, involve the
RBC enzymes glucose-6-phosphate dehydrogenase
and pyruvate kinase.
GLUCOSE-6-PHOSPHATE DEHYDROGENASE

Glucose-6-phosphate dehydrogenase is an enzyme
pivotal in generating the reduced form of nicotinamide adenine dinucleotide phosphate (NADPH)
through the pentose pathway in glucose metabolism.
More than 100 structural and functional variants of
the normal G-6-PD molecule (called type B) have
been identified, most of which are clinically insignificant. One variant form (called type A) does,
however, produce clinical disease. The type A variant
is caused by a sex-linked genetic defect. The abnormal gene is carried by women and is transmitted to
men who inherit the disorder.
Persons with the type A enzyme (15 percent of
blacks) experience no difficulty until challenged by
an oxidative stressor, which induces rapid intravascular hemolysis of susceptible cells. Among these
stressors are systemic infections, septicemia, metabolic acidosis, and exposure to oxidant drugs
(aspirin, chloramphenicol [Chloromycetin], nitrofurantoin [Furadantin], phenacetin, primaquine,

probenecid [Benemid], quinidine, quinine, sulfonamides, thiazide diuretics, and tolbutamide
[Orinase]).
A Mediterranean variant also may occur, especially in individuals of Greek and Italian descent and
in some small, inbred Jewish populations. This variant severely reduces enzymatic activity and leads to
more severe hemolytic episodes, which are triggered
by a greater variety of stimuli and are less likely to be
self-limited than in persons with the type A variant.
In addition to the oxidative stressors just listed,
ingestion of fava beans is known to precipitate
hemolytic events in individuals with Mediterraneantype G-6-PD deficiency.32
PYRUVATE KINASE

Pyruvate kinase (PK) functions in the formation of
pyruvate and adenosine diphosphate (ADP) in
glycolysis. The pyruvate thus formed is subsequently
converted to lactate. RBCs that lack PK have a low
affinity for oxygen. Episodes of hemolysis in individuals lacking this enzyme are severe and chronic and
are exacerbated by stressors such as infection.
The inherited form of this disorder is transmitted
as an autosomal recessive trait; both parents must
carry the abnormal gene for the child to be affected.
The acquired form of PK deficiency is usually caused
by either drug ingestion or metabolic liver disease.
INTERFERING FACTORS

Young RBCs have higher enzyme levels than do
older ones; thus, if the tests are performed within 10
days of a hemolytic episode (when the body is
actively replacing lost cells through increased
erythropoiesis) or after a recent blood transfusion,
the results may be falsely normal.
INDICATIONS FOR RED BLOOD CELL
ENZYMES STUDY

Hemolytic anemia of uncertain etiology, especially when it occurs in infancy or early childhood

Reference Values
Conventional Units
G-6-PD

4.3–11.8 IU/g Hgb

0.28–0.76 mm/mol Hgb

125–281 U/dL packed RBCs (PRBCs)

1.25–2.81 kU/L RBC

251–511 U/10 cells
1211–2111 IU/mL PRBCs
PK

SI Units

2.0–8.8 U/g Hgb
0.3–0.91 mg/dL

0.25–0.51 nU/L RBC

CHAPTER 1—Hematology

Suspected G-6-PD or PK deficiency, especially in
individuals with positive family history or with
jaundice occurring in response to stressors,
oxidant drugs, or foods such as fava beans
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a lavender-topped tube. A capillary
sample may be collected in infants and children as
well as in adults for whom venipuncture may not be
feasible.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Abnormal test results, complications, and precautions: Respond as for any laboratory analysis to
determine RBC abnormalities leading to anemia.

ERYTHROCYTE SEDIMENTATION RATE
The erythrocyte sedimentation rate (ESR or sed
rate) measures the rate at which RBCs in anticoaguTABLE 1–10

•

and Tests of Hematopoietic Function

lated blood settle to the bottom of a calibrated tube.
In normal blood, relatively little settling occurs
because the gravitational pull on the RBCs is almost
balanced by the upward force exerted by the plasma.
If plasma is extremely viscous or if cholesterol levels
are very high, the upward trend may virtually
neutralize the downward pull on the RBCs. In
contrast, anything that encourages RBCs to aggregate or stick together increases the rate of settling.
Inflammatory and necrotic processes, for example,
cause an alteration in blood proteins that results in
clumping together of RBCs because of surface
attraction. These clumps are called rouleaux. If the
proportion of globin to albumin increases or if
fibrinogen 3 levels are especially high, rouleaux
formation is enhanced and the sed rate increases.33
Specific causes of altered ESRs are presented in Table
1–10.
INTERFERING FACTORS

Delays in performing the test after the sample is
collected may retard the ESR and cause abnormally
low results; the test should be performed within 3
hours of collecting the sample.
INDICATIONS FOR ERYTHROCYTE
SEDIMENTATION RATE TEST

Suspected organic disease when symptoms are
vague and clinical findings uncertain

Causes of Altered Erythrocyte Sedimentation Rates

Increased Rate

Decreased Rate

Pregnancy (uterine and ectopic)

Polycythemia vera

Toxemia of pregnancy

Congestive heart failure

Collagen disorders (immune disorders of connective
tissue)

Sickle cell, Hgb C disease

Inflammatory disorders

Degenerative joint disease

Infections

Cryoglobulinemia

Acute myocardial infarction

Drug toxicity (salicylates, quinine derivatives,
adrenal corticosteroids)

Most malignancies
Drugs (oral contraceptives, dextran, penicillamine,
methyldopa, procainamide, theophylline, vitamin A)
Severe anemias
Myeloproliferative disorders
Renal disease (nephritis)
Hepatic cirrhosis
Thyroid disorders
Acute heavy metal poisoning

SECTION I—Laboratory

Tests

Reference Values
Normal values for the ESR follow. Note that several laboratory methods can be
used to determine the ESR. Values vary according to the method used.
Wintrobe (mm/hr)

Westergren (mm/hr)

Men

Cutler (mm/hr)
0–8

50 yr

0–7

0–15

50 yr

5–7

0–20

Women

0–10

50 yr

0–15

0–20

50 yr

25–30

0–30

Landau Micro Method

Smith Micro Method

Children
Newborn–2 yr

1–6

0–1 (newborns)

4–14 yr

1–9

3–13

Identification of the presence of an inflammatory
or necrotic process
Monitoring response to treatment for various
inflammatory disorders (e.g., rheumatoid arthritis, systemic lupus erythematosus)
Support for diagnosing disorders associated with
altered ESRs (see Table 1–10)

increases, note signs of infection or inflammation
(pain, temperature) and activity intolerance
(fatigue, weakness), and perform activities that
conserve the client’s energy. Administer ordered
anti-inflammatory or antibiotic therapy. As the
rate decreases, evaluate for improvement in
condition and possible increases in client activity.

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a lavender-topped tube. A capillary
sample may be obtained in infants and children as
well as in adults for whom venipuncture may not be
feasible.
The sample should be transported promptly to
the laboratory, because the test must be performed
within 3 hours of collecting the sample. Delays may
retard the ESR and cause abnormally low results.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Abnormal values: Note and report increases or
decreases in the rate in relation to other test
results used to determine the presence of or to
monitor the progress of a disease. As the rate

LEUKOCYTE STUDIES
Leukocytes (white blood cells, WBCs) constitute the
body’s primary defense against “foreignness”; that is,
leukocytes protect the body from foreign organisms,
substances, and tissues. The main types of leukocytes are neutrophils, monocytes, eosinophils,
basophils, and lymphocytes. All of these cells are
produced in the bone marrow. However, lymphocytes may be produced in additional sites. Each of
these types of leukocytes has different functions, and
each behaves as a related but different system.34
Neutrophils and monocytes, the most mobile and
active phagocytic leukocytes, are capable of breaking
down various proteins and lipids such as those in
bacterial cell membranes. The function of
eosinophils is uncertain, although they are believed
to detoxify foreign proteins that enter the body
through the lungs or intestinal tract. The function of
basophils also is not clearly understood, but the cells
themselves are known to contain heparin, histamine,
and serotonin. Basophils are believed to cause
increased blood flow to injured tissues while
preventing excessive intravascular clotting.

CHAPTER 1—Hematology

Lymphocytes play an important role in immunity
and may be divided into two main categories, B
lymphocytes and T lymphocytes. B lymphocytes are
responsible for humoral immunity and antibody
production. It is B lymphocytes that ultimately
develop into the antibody-producing plasma cells
(see Fig. 1–2). T lymphocytes are responsible for
cellular immunity and they interact directly with the
antigen.35,36 Lymphocytes and related studies are
discussed in greater detail in Chapter 3.
Note that leukocytes perform their functions
outside the vascular bed. Thus, WBCs are merely in
transit while in the blood. Because of the many
leukocyte functions, alterations in the number and
types of cells may be indicative of numerous pathophysiologic problems.

WHITE BLOOD CELL COUNT
The WBC count determines the number of leukocytes per cubic millimeter of whole blood. The
counting is performed very rapidly by electronic
devices. The WBC may be performed as part of a
CBC, alone, or with differential WBC count. An
elevated WBC count is termed leukocytosis; a
decreased count, leukopenia. In addition to the
normal physiological variations in WBC count,
many pathological problems may result in an abnormal WBC count (see Table 1–2).
If the WBC count is low, a buffy coat smear can be
performed to identify leukemia or solid tumor cells
in the blood. An alteration in total WBC count indicates the degree of response to a pathological process
but is not specifically diagnostic for any one disorder. A more complete evaluation is obtained through
the differential WBC count.
INDICATIONS FOR A WHITE BLOOD CELL COUNT

Routine screening as part of a CBC
Suspected inflammatory or infectious process (see
Table 1–2)

and Tests of Hematopoietic Function

Suspected leukemia, autoimmune disorder, or
allergy
Suspected bone marrow depression
Monitoring response to stress, malnutrition, and therapy for infectious or malignant
processes
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a lavender-topped tube. A capillary
sample may be obtained in infants and children as
well as in adults for whom venipuncture may not be
feasible.
Because of the normal diurnal variation of WBC
levels, it is important to note the time when the
sample was obtained.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Abnormal test results: Provide support when
diagnostic findings are revealed, especially if
malignancy is a possibility or is confirmed.
Reinforce information given by the physician, and
answer questions or direct them to the appropriate professionals.
Abnormal values: Note and report signs and
symptoms of infection or inflammation associated with an increased count (temperature,
chills), including those reflective of the site
affected (pain, edema, redness, drainage). Carry
out appropriate standard precautions to prevent
spread to other sites. Collect a specimen for
culture and sensitivities. Administer ordered
antipyretic and antibiotic therapy to treat infec-

Reference Values
The normal range of WBCs for adults is 5,000 to 10,000. Variations in the WBC count across the life cycle
are shown in Table 1–4 . Abnormal results may be classified by degree of severity as indicated.
Elevations

Decreases

Conventional Units

SI Units

Conventional Units

SI Units

Slight

11,000–20,000

11.0–20.0 109 L

3000–4500

3.4–4.5 109 L

Moderate

20,000–30,000

20.0–30.0 109 L

1500–3000

1.5–3.0 109 L

50,000

50.0 109 L

Severe

1500

1.5 109 L

SECTION I—Laboratory

Tests

tion. Administer chemotherapeutic agents for
malignancy identified and monitored by WBC
and differential counts. Note and report decreased
count and carry out reverse isolation procedures
to protect immunosuppressed client from infection.
Critical values: Notify the physician at once if a
new client has a WBC count of less than 2,000
per microliter or greater than 50,000 per microliter or if a client whose WBC count was less
than 4,000 per microliter has a change of 1,000
per microliter. Take precautions to protect the
client from infection. Prepare for further diagnostic procedures to identify the cause or
source of increases or decreases in the count.

DIFFERENTIAL WHITE BLOOD
CELL COUNT
The differential WBC count indicates the percentage
of each type of leukocyte present per cubic millime-

TABLE 1–11

•

Causes of Altered White Blood Cell Differential by Cell Type

Cell Type
Neutrophils

ter of whole blood. If necessary for further evaluation of results, the percentage for each cell type can
be multiplied by the total WBC count to obtain the
absolute number of each cell type present.
Causes of alterations in the differential WBC
count according to type of leukocyte are presented
in Table 1–11. An increase in immature neutrophils
(i.e., bands, stabs) indicates the body’s attempt to
produce more neutrophils in response to the pathological process. A decreased neutrophil count is
fairly common in children during viral infections.
An increase in bands is sometimes referred to as a
“shift to the left.” This terminology derives from the
following traditional headings used on laboratory
slips to report WBC differential results: Bands,
Neutrophils, Eosinophils, Basophils, Monocytes, and
Lymphocytes.
In contrast, the meaning of a “shift to the right” is
less well defined. This may refer to an increase in
neutrophils or other granulocytes or to an increase
in lymphocytes or monocytes.

Increased Levels
Stress (allergies, exercise, childbirth,
surgery)
Acute hemorrhage or hemolysis

Bone marrow depression (viruses, toxic
chemicals, overwhelming infection,
Felty’s syndrome, Gaucher’s disease,
myelofibrosis, hypersplenism, pernicious anemia, radiation)

Infectious diseases

Anorexia nervosa, starvation, malnutrition

Inflammatory disorders (rheumatic fever,
gout, rheumatoid arthritis, drug reactions, vasculitis, myositis)

Folic acid deficiency

Tissue necrosis (burns, crushing injuries,
abscesses

Acromegaly

Malignancies

Addison’s disease

Metabolic disorders (uremia, eclampsia,
diabetic ketoacidosis, thyroid crisis,
Cushing’s syndrome)

Thyrotoxicosis

Drugs (epinephrine, histamine, lithium,
heavy metals, heparin, digitalis, ACTH)

Disseminated lupus erythematosus

Toxins and venoms (turpentine, benzene)

Drugs (alcohol, phenylbutazone
[Butazolidin], phenacetin, penicillin,
chloramphenicol, streptomycin, phenytoin [Dilantin], mephenytoin
[Mesantoin], phenacemide [Phenurone],
tripelennamine [PBZ], aminophylline,
quinine, chlorpromazine, barbiturates,
dinitrophenols, sulfonamides, antineoplastics)

Extremes of temperature

Leukemia (myelocytic)

Bands (immature
neutrophils)

Decreased Levels

Infections

Vitamin B12 deficiency

Anaphylaxis

None, as bands should be absent or present only in small numbers
(Continued )

CHAPTER 1—Hematology

TABLE 1–11

•

and Tests of Hematopoietic Function

Causes of Altered White Blood Cell Differential by Cell Type

Cell Type

Increased Levels

Decreased Levels

Antineoplastic drugs
Any condition that causes neutrophilia
Leukemia

Basophils

None, as normal value is 0–1%

Hodgkin’s disease
Polycythemia vera
Ulcerative colitis
Nephrosis
Chronic hypersensitivity states
Eosinophils

Sickle cell disease

Disseminated lupus erythematosus

Asthma

Acromegaly

Chorea

Elevated steroid levels

Hypersensitivity reactions

Stress

Parasitic infestations

Infectious mononucleosis

Autoimmune diseases

Hypersplenism

Addison’s disease

Cushing’s syndrome

Malignancies

Congestive heart failure

Sarcoidosis

Hyperplastic anemia

Chronic inflammatory diseases and
dermatoses

Hormones (ACTH, thyroxine, epinephrine)

Leprosy
Hodgkin’s disease
Polycythemias
Ulcerative colitis
Autoallergies
Pernicious anemia
Splenectomy
(Continued on following page)

Reference Values
The normal percentage of each WBC type in
adults is shown next. Variations across the life
cycle are listed in Table 1–4.
Conventional Units
Bands

SI Units

3–8%

0.03–0.08

Neutrophils

54–75%

0.54–0.75

Eosinophils

1–4%

0.01–0.04

Basophils

0–1%

0–0.01

2–8%

0.02–0.08

25–40%

0.25–0.40

Monocytes
Lymphocytes

INDICATIONS FOR DIFFERENTIAL WHITE
BLOOD CELL COUNT

Routine screening as part of a CBC
Abnormal total WBC count to determine the
source of the elevation
Confirmation of the presence of various disorders associated with increases and decreases in
the several types of WBCs (see Table 1–11)
Monitoring of response to treatment for acute
infections, with a therapeutic response indicated
by a decreasing number of bands and a stabilizing
number of neutrophils
Monitoring of physiological responses to
chemotherapy

SECTION I—Laboratory

TABLE 1–11

•

Tests

Causes of Altered White Blood Cell Differential by
Cell Type (Continued)

Cell Type
Monocytes

Increased Levels
Infections (bacterial, viral, mycotic, rickettsial, amebic)

Decreased Levels
Not characteristic of specific disorders

Cirrhosis
Collagen diseases
Ulcerative colitis
Regional enteritis
Gaucher’s disease
Hodgkin’s disease
Lymphomas
Carcinomas
Monocytic leukemia
Radiation
Polycythemia vera
Sarcoidosis
Weil’s disease
Systemic lupus erythematosus
Hemolytic anemias
Thrombocytopenic purpura
Lymphocytes

Infections (bacterial, viral)

Immune deficiency diseases

Lymphosarcoma

Hodgkin’s disease

Ulcerative colitis

Rheumatic fever

Banti’s disease

Aplastic anemia

Felty’s syndrome

Bone marrow failure

Myeloma

Gaucher’s disease

Lymphomas

Hemolytic disease of the newborn

Addison’s disease

Hypersplenism

Thyrotoxicosis

Thrombocytopenic purpura

Malnutrition

Transfusion reaction

Rickets

Massive transfusions

Waldenström’s macroglobulinemia

Pernicious anemia

Lymphocytic leukemia

Septicemia
Pneumonia
Burns
Radiation
Toxic chemicals (benzene, bismuth, DDT)
Antineoplastic agents
Adrenal corticosteroids (high doses)

CHAPTER 1—Hematology

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).

WHITE BLOOD CELL ENZYMES

LEUKOCYTE ALKALINE PHOSPHATASE

WBCs in peripheral blood samples retain enzymatic
activity and can alter substrates added in the labora-

•

tory. The presence of enzymatic activity is useful in
studying cells that are so morphologically abnormal
on stained smear that it is difficult to determine their
cell line of origin (see Fig. 1–2). The two most
common WBC enzyme tests are the test for leukocyte alkaline phosphatase, an enzyme found in
neutrophils, and the periodic acid–Schiff stain,
which tests for enzymes found in granulocytes and
erythrocytes. Both tests are used to diagnose hematologic disorders, especially leukemias. Specific
causes of alterations in WBC enzymes are presented
in Table 1–12. Another WBC enzyme test, tartrateresistant acid phosphatase (TRAP), is performed to
diagnose hairy cell leukemia, because this enzyme
activity is present in the lymphocytic cells of this
type of leukemia. Additional details for each test are
briefly discussed subsequently.

NURSING CARE BEFORE THE PROCEDURE

TABLE 1–12

and Tests of Hematopoietic Function

Leukocyte alkaline phosphatase (LAP) is an enzyme

Causes of Alterations in White Blood Cell Enzymes
Causes of Alterations

Enzyme
Leukocyte alkaline phosphatase
(LAP)

Elevated Levels

Decreased Levels

Chronic myelocytic leukemia

Acute myelocytic leukemia

Polycythemia vera

Acute monocytic leukemia

Myelofibrosis

Chronic granulocytic leukemia

Leukemoid reactions

Anemias (aplastic, pernicious)

Oral contraceptives

Thrombocytopenia

Pregnancy

Infectious mononucleosis

Adrenocorticotropic hormone (ACTH)
excess

Paroxysmal nocturnal hemoglobinuria

Cushing’s syndrome

Hereditary hypophosphatasia

Down syndrome

Collagen diseases

Multiple myeloma
Lymphomas
Positive
Periodic
acid–Schiff (PAS)
stain

Negative

Acute granulocytic leukemia

Early granulocyte precursors

Acute lymphoblastic leukemia

Severe iron-deficiency anemia

Erythroleukemia

Normal erythrocyte precursors

Amyloidosis

Mature RBCs

Thalassemia
Lymphomas

SECTION I—Laboratory

Tests

Reference Values
Leukocyte alkaline phosphatase

13–130 U

Periodic acid–Schiff stain

Granulocytes—positive
Agranulocytes—negative
Granulocytic precursors—negative
Erythrocytes—negative
Erythrocytic precursors—negative

Tartrate-resistant acid phosphatase
found in neutrophils. This enzyme is completely
independent of serum alkaline phosphatase, which
reflects osteoblastic activity and hepatic function.
The LAP content of neutrophils increases as the cells
mature; therefore, the LAP study is useful in assessing cellular maturation and in evaluating departures
from normal differentiation.
The LAP study is used to distinguish among various hematologic disorders. For example, LAP
increases in polycythemia vera, myelofibrosis, and
leukemoid reactions to infections, but decreases in
chronic granulocytic leukemia. Because all of these
conditions have increased numbers of immature
circulating neutrophils, LAP scores can be helpful in
differentiating among them.
PERIODIC ACID–SCHIFF STAIN

In the periodic acid–Schiff (PAS) stain, compounds
that can be oxidized to aldehydes are localized by
brilliant fuschia staining. Many elements in many
tissues are PAS-positive, but in blood cells the PASpositive material of diagnostic importance is cytoplasmic glycogen. Early granulocytic precursors and
normal erythrocytic precursors are PAS-negative.
Mature RBCs remain PAS-negative, but granulocytes acquire increasing PAS positivity as they
mature.37
INDICATIONS FOR WHITE BLOOD CELL
ENZYMES STUDY

Identification of morphologically abnormal
WBCs on stained smear
Suspected leukemia or other hematologic disorders (see Table 1–12, p. 37)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A capillary sample is generally preferred for these

Activity absent
tests. The sample is spread on a slide, fixed, and
stained.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
REFERENCES
1. Porth, CM: Pathophysiology: Concepts of Altered States, ed 5. JB
Lippincott, Philadelphia, 1998, p 113.
2. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, p 21.
3. Ibid, p 21.
4. Ibid, p 21.
5. Hillman, RS, and Finch, CA: Red Cell Manual, ed 7. FA Davis,
Philadelphia,1996, p 2.
6. Price, S, and Wilson, L: Pathophysiology, ed 3. McGraw-Hill, New
York, 1986, p 180.
7. Porth, op cit, p 114.
8. Sacher and McPherson, op cit, p 30.
9. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed 4.
JB Lippincott, Philadelphia, 1992, pp 89–91.
10. Hillman and Finch, op cit, pp 4–5.
11. Sacher and McPherson, op cit, p 32.
12. Hillman and Finch, op cit, pp 6–7.
13. Sacher and McPherson, op cit, p 32.
14. Ibid, p 41.
15. Ibid, p 41.
16. Ibid, p 43.
17. Ibid, p 32.
18. Hillman and Finch, op cit, pp 95–96.
19. Fischbach, op cit, p 88.
20. Hillman and Finch, op cit, p 42.
21. Sacher and McPherson, op cit, p 45.
22. Hillman and Finch, op cit, p 12.
23. Fischbach, op cit, p 43.
24. Sacher and McPherson, op cit, p 46.
25. Hillman and Finch, op cit, p 43.
26. Hole, JW: Human Anatomy and Physiology, ed 4. Wm C Brown,
Dubuque, Iowa, p 603.
27. Hillman and Finch, op cit, p 43.
28. Sacher and McPherson, op cit, p 44.
29. Hillman and Finch, op cit, pp 10–11.
30. Ibid, pp 87, 110.
31. Fischbach, op cit, p 82.
32. Sacher and McPherson, op cit, pp 99–100.
33. Ibid, pp 67–68.
34. Boggs, DR, and Winkelstein, A: White Cell Manual, ed 4. FA Davis,
Philadelphia, 1983, p 1.
35. Hole, op cit, pp 625–627.
36. Boggs and Winkelstein, op cit, pp 63–65.
37. Sacher and McPherson, op cit, pp 70–71.

CHAPTER

Hemostasis and Tests of
Hemostatic Functions
TESTS COVERED
Platelet Count, 42
Bleeding Time, 44
Platelet Aggregation Test, 46
Clot Retraction Test, 47
Rumple-Leeds Capillary Fragility Test
(Tourniquet Test), 48
Prothrombin Time, 49
Partial Thromboplastin Time/Activated
Partial Thromboplastin Time, 51

Whole Blood Clotting Time
(Coagulation Time, Lee-White
Coagulation Time), 52
Thrombin Clotting Time, 53
Prothrombin Consumption Time, 54
Factor Assays, 55
Plasma Fibrinogen, 57
Fibrin Split Products, 58
Euglobulin Lysis Time, 58

INTRODUCTION Hemostasis is the collective term for all the mechanisms the body uses to
protect itself from blood loss. In other words, failure of hemostasis leads to hemorrhage.
Hemostatic mechanisms are organized into three categories: (1) vascular activity, (2) platelet
function, and (3) coagulation.

VASCULAR ACTIVITY
Vascular activity consists of constriction of muscles
within the walls of the blood vessels in response to
vascular damage. This vasoconstriction narrows the
path through which the blood flows and may sometimes entirely halt blood flow. The vascular phase of
hemostasis affects only arterioles and their dependent capillaries; large vessels cannot constrict sufficiently to prevent blood loss. Even in small vessels,
vasoconstriction provides only a brief hemostasis.

PLATELET FUNCTION
Platelets serve two main functions: (1) to protect
intact blood vessels from endothelial damage
provoked by the countless microtraumas of day-today existence and (2) to initiate repair through the

formation of platelet plugs when blood vessel walls
are damaged.
When overt trauma or microtrauma damages
blood vessels, platelets adhere to the altered surface.
Adherence requires the presence of ionized calcium
(coagulation factor IV), fibrinogen (coagulation
factor I), and a protein associated with coagulation
factor VIII, called von Willebrand’s factor (vWF).
The process of adherence involves reversible changes
in platelet shape and, usually, the release of adenosine diphosphate (ADP), adenosine triphosphate
(ATP), calcium, and serotonin. With a strong
enough stimulus, the next phase of platelet activity,
platelet aggregation, occurs and results in the
formation of a loose plug in the damaged endothelium. The platelet plug aids in controlling bleeding
until a blood clot has had time to form.1
39

SECTION I—Laboratory

Tests

Platelets generate prostaglandins that ultimately
promote platelet adherence, whereas the endothelial
cells lining the blood vessels produce a different
prostaglandin that inhibits platelet aggregation.
Ingestion of aspirin inhibits the actions of the
prostaglandins released by platelets, an effect that
may persist for many days after a person takes even
a small amount of aspirin. Aspirin also may affect
the actions of the prostaglandins produced by
endothelial cells, but not to the extent that it affects
platelet prostaglandins.2 Thus, the net effect of
aspirin is to inhibit hemostasis.
Thrombin, which is generated by the coagulation
sequence (see the next section), independently
promotes the release of substances from the
platelets. Release of platelet factor 3 enhances coagulation mechanisms, thereby increasing thrombin
generation. Platelet factor 4, also released by
platelets, reinforces the interactions between coagulation and platelet aggregation by neutralizing the
naturally generated anticoagulant, endogenous
heparin.3

COAGULATION
Coagulation is a complex process by which plasma
proteins interact to form a stable fibrin gel.4 The
fibrin strands thus formed create a meshwork that
cements blood components together, a process
known as syneresis. Ultimately, a blood clot is
formed.5,6 Normal coagulation depends on the presence of all clotting factors and follows specific
sequences known as pathways or cascades.
At least 30 substances are believed to be involved
in the clotting process. The most significant ones
are shown in Table 2–1. Note that clotting factors
are now designated by Roman numerals. The
“a” indicates an activated clotting factor.7 There is
no factor VI because that number was originally assigned to what is now known to be activated
factor V.8
Each of the clotting factors is involved at a specific
step in the coagulation process, with one clotting
factor leading to activation of the next factor in the
sequence. Three major clotting sequences have been
identified: (1) the intrinsic pathway, (2) the extrinsic
pathway, and (3) the common final pathway.
The intrinsic pathway is activated when blood
comes in contact with the injured vessel wall; the
extrinsic pathway is activated when blood is exposed
to damaged tissues. Both pathways are needed for
normal hemostasis, and both lead to the common
final pathway.9 A schematic representation of the
intrinsic, extrinsic, and common pathways is shown
in Figure 2–1.

TABLE 2–1

•

Clotting Factors

Fibrinogen

Fibrin

Prothrombin

IIa

Thrombin

III

Thromboplastin, tissue
thromboplastin

Calcium, ionized calcium

Accelerator globulin (AcG),
proaccelerin, labile factor

VII

Proconvertin, autoprothrombin
I, serum prothrombin conversion
accelerator (SPCA)

VIIa

Convertin

VIII

Antihemophilic factor (AHF),
antihemophilic globulin (AHG)

Christmas factor, antihemophilic
factor B, plasma thromboplastin
component (PTC), autoprothrombin II

Stuart factor, Stuart-Prower
factor, autoprothrombin III

Plasma thromboplastin
antecedent (PTA)

XII

Hageman factor

XIII

Fibrin-stabilizing factor

The common final pathway is initiated with the
activation of factor X. Factors X and V, along with
platelet phospholipid and calcium, combine to form
prothrombin activator, which converts prothrombin
to thrombin. Thrombin subsequently converts
fibrinogen to fibrin gel. Thrombin also enhances
platelet release reactions, augments the activation of
factors V and VIII, and activates factor XIII.10 Stable
(insoluble) fibrin is formed in the presence of activated factor XIII.
Calcium plays an important role throughout the
coagulation process. It is necessary for the activation
of factors VII, IX, X, and XI; for the conversion of
prothrombin (factor II) to thrombin; and for the
formation of fibrin. However, hypocalcemia does
not usually cause bleeding difficulties because
cardiac arrest occurs before levels are low enough to
precipitate abnormal hemostasis. Citrate, oxalate,
and ethylenediaminetetra-acetic acid (EDTA) are
anticoagulants because they bind calcium and
prevent it from participating in the clotting process.
Any one of these substances may be added to the
vacuum tubes used to collect peripheral blood

CHAPTER 2—Hemostasis

and Tests of Hemostatic Functions

Image/Text rights unavailable

samples when an uncoagulated specimen is needed
(see Appendix I, Table A–1).11

ANTAGONISTS TO HEMOSTASIS
Both platelet activation and coagulation are selfperpetuating processes that could potentially
continue until an injured vessel is completely
occluded. Coagulation inhibitors are present to
prevent excessive clotting and to dissolve the clot as
tissue repair occurs.
Maintaining adequate blood flow aids in diluting
and removing clotting factors and in dispersing
aggregated platelets. Partially activated coagulation
factors are carried to the liver and the reticuloendothelial system, where they are degraded.12 Two
specific anticoagulation mechanisms also help to
prevent excessive clotting: (1) the fibrinolytic system
and (2) the antithrombin system.
In the fibrinolytic system, fibrin strands are
broken down into progressively smaller fragments
by a proteolytic enzyme, plasmin. Although plasmin
does not circulate in active form, its precursor, plas-

minogen, does. Plasminogen is converted into plasmin by several plasminogen activators, among them
factor XII, urokinase, and streptokinase. Once activated, plasmin digests fibrin, splits fibrinogen into
peptide fragments (fibrin split products [FSP]), and
degrades factors V, VIII, and XIII. In addition, the
FSP interfere with platelet aggregation, reduce
prothrombin, and interfere with conversion of soluble fibrin to insoluble fibrin. Plasma also contains
agents that neutralize plasmin itself. Among these
are antiplasmin and 1-antitrypsin. A balance
between proplasmin and antiplasmin substances
aids in maintaining normal coagulation.13
The antithrombin system protects the body from
excessive clotting by neutralizing the clotting capability of thrombin.14 Although various substances
inhibit thrombin, the most important one is
antithrombin III (AT III), a substance that abolishes
the activity of thrombin (activated factor II); activated factors X, XI, and XII; and plasmin. Another
name for AT III is heparin cofactor. Heparin
augments by approximately 100 times the affinity of
AT III and the activated clotting factors on which it

SECTION I—Laboratory

Tests

acts. A deficiency of AT III, which can be congenital
or acquired, makes an individual prone to excessive
clotting. Platelet factor 4, which is released when
platelets are broken down, inhibits AT III activity.15

• Overview of Causes
of Altered Platelet Function

TABLE 2–2

Increased
Function

Decreased
Function

PLATELET STUDIES

Trauma

Circulating platelets (thrombocytes) are anuclear,
cytoplasmic disks that bud off from megakaryocytes,
large multinucleated cells found in the bone
marrow16,17 (see Fig. 1–2). Platelets survive in the
circulation for about 10 days.
Regulation of platelet production is ascribed to
thrombopoietin by analogy to erythropoietin (see
Chapter 1), although no single substance has been
specifically identified. With pronounced hemostatic
stress or marrow stimulation, platelet production
can increase to seven to eight times that of normal
production. Newly generated platelets are larger and
have greater hemostatic capacity than mature circulating platelets.18
Two thirds of the total number of platelets are in
the systemic circulation, and the remaining third
exists as a pool of platelets in the spleen. The pool
exchanges freely with the general circulation.19 The
spleen also aids in removing old or damaged
platelets from the circulation. In disorders involving
exaggerated splenic activity (hypersplenism), 90
percent of the body’s platelets may be trapped in the
enlarged spleen, and the client is predisposed to
excessive bleeding. Hypersplenism is seen in certain
acute infections (e.g., infectious mononucleosis,
miliary tuberculosis), connective tissue diseases
(e.g., rheumatoid arthritis, lupus erythematosus),
myeloproliferative diseases (e.g., leukemias,
lymphomas, hemolytic anemias), and chronic liver
diseases (e.g., cirrhosis).20
The functions of platelets are discussed in the
introduction to this chapter. In general, individuals
with too few platelets or with platelets that function
poorly experience numerous pinpoint-sized hemorrhages (petechiae) and multiple small, superficial
bruises (ecchymoses). Frequently, there is generalized oozing from mucosal surfaces and from
venipuncture sites or other small, localized injuries.
Large, deep hematomas and bleeding into joints are
not characteristic of platelet deficiency (thrombocytopenia).21
Platelet studies involve evaluating the number
and function of circulating platelets. Platelet
numbers are assessed by the platelet count (see the
next section). Disorders of platelet function (thrombopathies) are less common than disorders of
platelet number. An overview of the causes of altered
platelet function is provided in Table 2–2.

Surgery

Uremia

Fractures

Myeloproliferative disorders

Strenuous
exercise

Dysproteinemias

Severe liver disease

Glanzmann’s thrombasthenia
Pregnancy

Bernard-Soulier syndrome
(hereditary giant platelet
syndrome)
Idiopathic thrombocytopenic
purpura
Infectious mononucleosis
von Willebrand’s disease
Drugs such as aspirin and
other anti-inflammatory
agents, antihistamines, antidepressants, alcohol,
methylxanthines

PLATELET COUNT
Platelets may be counted manually or with electronic counting devices. Although larger numbers of
platelets are capable of being examined with electronic counting, the procedure is subject to error if
(1) the white blood cell (WBC) count is greater than
10,000 cells per cubic millimeter, (2) there is severe
red blood cell fragmentation, (3) the diluting fluid
contains extraneous particles, (4) the plasma sample
settles too long during processing, or (5) platelets
adhere to one another.
Causes of increased numbers of platelets (thrombocytosis, thrombocythemia) and decreased
numbers of platelets (thrombocytopenia) are
presented in Table 2–3.
Mean platelet volume can also be determined by
the electronic automated method. The test reveals
the size of platelets important in the diagnosis of
disorders affecting the hematologic system. An
increased volume of platelets that are larger than
normal in diameter is found in lupus erythematosus, thrombocytopenic purpura, B12-deficiency
anemia, hyperthyroidism, and myelogenic and other
myeloproliferative diseases. A decreased volume of
the larger sized platelets is found in Wiskott-Aldrich
syndrome.22

CHAPTER 2—Hemostasis

TABLE 2–3

•

and Tests of Hemostatic Functions

Causes of Altered Platelet Levels
Decreased Levels (Thrombocytopenia)

Increased Levels
(Thrombocytosis)

Decreased
Production

Increased
Destruction

Leukemias (chronic)

Vitamin B12/folic acid deficiencies

Idiopathic thrombocytopenic purpura

Polycythemia vera

Radiation

Splenomegaly caused by liver
disease

Anemias (posthemorrhagic
and iron-deficiency)

Viral infections

Lymphomas

Splenectomy

Leukemias (acute)

Hemolytic anemias

Tuberculosis and other
acute infections

Histiocytosis

Rocky Mountain spotted fever

Hemorrhage

Bone marrow malignancies

Sarcoidosis

Carcinomatosis

Fanconi’s syndrome

Meningococcemia

Trauma

Wiskott-Aldrich syndrome

Antibody/HLA-antigen reactions

Surgery

Uremia

Hemolytic disease of the newborn

Chronic heart disease

Drugs such as anticancer drugs,
anticonvulsants, alcohol, carbamates, chloramphenicol,
chlorothiazides, isoniazid, pyrazolones, streptomycin, sulfonamides, sulfonylureas

Congenital infections
(cytomegalovirus [CMV], herpes,
syphilis, toxoplasmosis)

Cirrhosis
Chronic pancreatitis
Childbirth
Drugs such as epinephrine

Disseminated intravascular coagulation (DIC)
Immune complex formation
Chronic cor pulmonale
Miliary tuberculosis
Burns
Drugs and chemicals such as aspirin,
benzenes, DDT, digitoxin, gold
salts, heparin, quinidine, quinine,
thiazides

Reference Values
Values vary slightly across the life cycle, with
lower platelet counts seen in newborns (see
Table 1–4).
150,000 to 450,000 per cubic millimeter (average 250,000 per cubic millimeter)
Mean platelet volume 25 m diameter

Critical values: 20,000 U/L or 1,000,000
U/L

INTERFERING FACTORS

Altered test results may occur if:
The WBC count is greater than 100,000 per
cubic millimeter.
There is severe red blood cell fragmentation.

The fluid used to dilute the sample contains
extraneous particles.
The plasma sample settles too long during
processing.
Platelets adhere to one another.
The client is receiving drugs that alter
platelet functions and numbers (see Tables 2–2
and 2–3).
Traumatic venipunctures may lead to erroneous
results as a result of activation of the coagulation
sequence.
Excessive agitation of the sample may cause the
platelets to clump together and adhere to the walls
of the test tube, thus altering test results.
INDICATIONS FOR PLATELET COUNT

Family history of bleeding disorder

SECTION I—Laboratory

Tests

Signs of abnormal bleeding such as epistaxis, easy
bruising, bleeding gums, hematuria, and menorrhagia
Determination of effects of diseases and drugs
known to alter platelet levels (see Table 2–3)
Identification of individuals who may be prone to
bleeding during surgical, obstetric, dental, or
invasive diagnostic procedures, as indicated by a
platelet count of approximately 50,000 to 100,000
per cubic millimeter
Identification of individuals who may be prone to
spontaneous bleeding, as indicated by a platelet
count of less than 15,000 to 20,000 per cubic
millimeter
Differentiation between decreased platelet
production and decreased platelet function:
Platelet dysfunction is defined as a long bleeding time with a platelet count of greater than
100,000/mm3.23
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

Care and assessment after the procedure are essentially the same as for any study involving the collection of a peripheral blood sample. Because the client
may have a platelet deficiency, maintain digital pressure directly on the puncture site for 3 to 5 minutes
after the needle is withdrawn. Also, inspect the site
for excessive bruising after the procedure.
Abnormal increase (thrombocytosis): Note and
report signs of dehydration and input and output
(I&O) ratio that can contribute to venous stasis,
possible thrombosis, or bleeding tendency if the
coagulation process is affected. Administer
ordered aspirin and antacid, and observe for
bleeding tendency if prothrombin time is
increased.
Abnormal decrease (thrombocytopenia): Note
and report petechiae, bruising, or hematoma.
Administer ordered corticosteroids. Protect children from trauma, advise adults to use soft toothbrushes and electric razors, and prevent other
trauma by padding side rails and avoiding intramuscular and subcutaneous injections. Assess

bleeding from skin and mucous membranes
(petechiae, ecchymoses, epistaxis, feces, urine,
emesis, sputum). Administer platelet transfusion
and assess for any allergic responses, sepsis, or
hypervolemia.
Critical values: Notify the physician immediately if the platelet count is less than 20,000/mL
or greater than 1 million/mL. Prepare for transfusion of platelets by intravenous drip or bolus
infusion.

BLEEDING TIME
One of the best indicators of platelet deficiency is
prolonged bleeding after a controlled superficial
injury; that is, capillaries subjected to a small, clean
incision bleed until the defect is plugged by aggregating platelets. When platelets are inadequate in
number or if their function is impaired, bleeding
time is prolonged.
If the platelet count falls below 10,000/mm3,
bleeding time is prolonged. Prolonged bleeding time
with a platelet count of greater than 100,000/mm3
indicates platelet dysfunction. Bleeding time is
prolonged in von Willebrand’s disease, an inherited
deficiency of vWF, a protein associated with clotting
factor VIII that is necessary for normal platelet
adherence. Aspirin ingestion also prevents platelet
aggregation and may prolong bleeding time for as
long as 5 days after a single 300-mg dose.24 Other
causes of prolonged bleeding times are listed in
Table 2–4.
Reference Values
Method

Normal Values

Duke

1–3 min

Ivy

3–6 min

Template

3–6 min

Values vary according to the method used to
perform the test (see the section on procedure).
When the platelet count is low, bleeding time may
be calculated from platelet numbers using the
following formula. The result should be evaluated in
relation to the normal values for the Ivy and
template methods.
Bleeding time 30.5 – platelet count/mm3
3850
The calculated value also may be compared with
the actual results of bleeding time obtained by the
Ivy and template methods. An actual bleeding time

CHAPTER 2—Hemostasis

TABLE 2–4

•

and Tests of Hemostatic Functions

Causes of Prolonged Bleeding Time

Drugs

Diseases

Alcohol

Aplastic anemia

Anticoagulants

Bernard-Soulier syndrome (hereditary
giant plate syndrome)

Aspirin and other salicylates
(OTC cold remedies, analgesics)

Connective tissue diseases

Chlorothiazides

Glanzmann’s thrombasthenia

High-molecular-weight dextran

Hepatic cirrhosis

Mithramycin

Hypersplenism

Streptokinase

Hypothyroidism

Sulfonamides

Leukemias

Thiazide diuretics

Malignancies such as Hodgkin’s disease and
multiple myeloma

Disseminated intravascular coagulation (DIC)

Measles
Mumps
Scurvy
von Willebrand’s disease

longer than the calculated result suggests defective
platelet function in addition to reduced numbers. It
is also possible to detect above-normal hemostatic
capacity in cases in which active young platelets
compose the entire population of circulating
platelets, because young platelets have enhanced
hemostatic capabilities.25 This phenomenon may be
seen in disorders involving increased platelet
destruction (see Table 2–3).
INTERFERING FACTORS

Ingestion of aspirin and aspirin-containing
medications within 5 days of the test may prolong
the bleeding time. Other drugs that may prolong
bleeding time are listed in Table 2–4.
INDICATIONS FOR BLEEDING TIME TEST

Family history of bleeding disorders, especially
von Willebrand’s disease (Tests of platelet adhesiveness and levels of factor VIII also are necessary
to confirm the diagnosis of von Willebrand’s
disease.)
Signs of abnormal bleeding such as epistaxis, easy
bruising, bleeding gums, hematuria, and menorrhagia
Thrombocytopenia as indicated by platelet count
Identification of individuals who may be prone to

bleeding during surgical, obstetric, dental, or
invasive diagnostic procedures
Determination of platelet dysfunction as indicated by a prolonged bleeding time with a platelet
count of greater than 100,000 per cubic millimeter
Determination of effects of diseases and drugs
known to affect bleeding time (see Table 2–4)
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test will be performed by a laboratory
technician and requires approximately 15 minutes
The procedure, including the momentary
discomfort to be expected when the skin is incised
Aspirin and aspirin-containing medications
should be withheld for at least 5 days before the test.
Other drugs that may prolong bleeding time (see
Table 2–4) should also be withheld.
THE PROCEDURE

The test may be performed using the Duke, Ivy, or
template method. All three methods involve piercing
the skin and observing the duration of bleeding time
from the puncture site. Welling blood must be
removed, but gently so as not to disrupt the fragile
platelet plug. After the skin is pierced, oozing blood

SECTION I—Laboratory

Tests

is removed at 15-second intervals by touching filter
paper to the drop of blood without touching the
wound itself. As platelets accumulate, bleeding slows
and the oozing drop of blood gets smaller. The end
point occurs when there is no fluid blood left to
produce a spot on the filter paper.26 The test is timed
with a stopwatch.
For all methods, the site to be used is cleansed
with antiseptic and allowed to dry. In the Duke
method, the earlobe is incised 3 mm deep with a
sterile lancet. For the Ivy and template methods, the
volar surface of the forearm is used. A blood pressure cuff is applied above the elbow and inflated to
40 mm Hg; the pressure is maintained throughout
the test. In the Ivy method, two incisions 3 mm deep
are made freehand with sterile lancets. In the
template method, two incisions, each 1 mm deep
and 9 mm long, are made with a standardized
template. The advantage of the template method is
the fact that it provides the ability to achieve a reproducible, precise incision every time.
The elapsed time at the point when bleeding
ceases is recorded. If bleeding persists beyond 10
minutes, the test is discontinued and a pressure
dressing is applied to the puncture site(s).
NURSING CARE AFTER THE PROCEDURE

When the test is completed, a sterile dressing or
Band-Aid is applied to the site. For persistent bleeding, ice may be applied to the site in addition to the
pressure dressing.
Observe the puncture site(s) every 5 minutes for
bleeding. Clients with clotting factor disorders
may rebleed after initial bleeding has stopped.
This may occur approximately 20 to 30 minutes
after the initial procedure.
Check the puncture site(s) at least twice daily for
infection or failure to heal.
For the Ivy and template methods, assess for
excessive bruising at the blood pressure cuff application site.

• Drugs That Impair
Platelet Aggregation

TABLE 2–5

Aminophylline

Phenothiazines

Antihistamines

Phenylbutazone

Anti-inflammatory drugs,
both steroids and
nonsteroidal types

Salicylates
Sulfinpyrazone

Caffeine

Tricyclic
antidepressants

Dipyridamole

of a test tube. Normally, platelet aggregates should
be visible in less than 5 minutes.
Platelet aggregation in response to specific inducing agents is diagnostic for specific disorders.
Aspirin, other anti-inflammatory agents, and many
phenothiazines markedly inhibit the aggregating
effect of collagen and epinephrine but do not interfere with the direct action of added ADP. Also,
conditions that depress the release-inducing effects
of collagen and epinephrine and of directly added
ADP affect platelet aggregation.
Individuals with von Willebrand’s disease have
platelets that respond normally to epinephrine,
collagen, and ADP. Without vWF in their plasma,
however, the platelets will not be aggregated by ristocetin.28
Other disorders that may impair platelet aggregation include Glanzmann’s thrombasthenia, BernardSoulier syndrome (hereditary giant platelet
syndrome), idiopathic thrombocytopenic purpura,
and infectious mononucleosis. Drugs that interfere
with platelet aggregation are listed in Table 2–5.
Reference Values
Platelet aggregates should be visible in less than
5 minutes.

PLATELET AGGREGATION TEST
Platelet aggregation can be measured by bringing
platelet-rich plasma into contact with known inducers of platelet aggregation. Most inducers, such as
collagen, epinephrine, and thrombin, act through
the effects of ADP, which is released by the platelets
themselves. Adding exogenous ADP causes platelet
aggregation directly. Ristocetin, an antibiotic, may
also be used for this test.27
Platelet aggregation is quantified by determining
whether platelet-rich plasma becomes clear as evenly
suspended platelets aggregate and fall to the bottom

INTERFERING FACTORS

Ingestion of aspirin and other drugs known to
interfere with platelet aggregation within 5 to 7
days of the test (see Table 2–5).
Delay in processing the sample or excessive agitation of the sample may alter test results.
INDICATIONS FOR PLATELET AGGREGATION TEST

Suspected von Willebrand’s disease or other
inherited platelet disorder
Evaluation of platelet aggregation in clients with

CHAPTER 2—Hemostasis

disorders known to cause alterations (e.g.,
uremia, severe liver disease, myeloproliferative
disorders, dysproteinemias)
Therapy with drugs known to alter platelet aggregation (see Table 2–5)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I). It is generally recommended that the person abstain from food for 8
hours before the test and, if possible, from drugs that
may impair platelet aggregation for 5 to 7 days
before the test.
THE PROCEDURE

and Tests of Hemostatic Functions

If fibrinogen levels are low, the initial clot is so
fragile that the fibrin strands rupture, and red blood
cells spill into serum when retraction begins. If there
is excessive fibrinolysis, as often happens with
reduced fibrinogen levels, the incubated tube may
contain only cells and fibrin with no fibrin clot at all.
Low fibrinogen levels and excessive fibrinolysis are
seen in disseminated intravascular coagulation
(DIC).29
The clot retraction test also can be modified to
demonstrate the inhibitory effect of antiplatelet
antibodies, especially those associated with drugs.
Clot retraction is abolished if more than 90 percent
of platelet activity is neutralized. Serum suspected of
containing antibodies can be added to normal blood
to see if retraction is inhibited.30

A venipuncture is performed and the sample
collected in a light-blue-topped tube.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are essentially the same as for any study involving the collection of a peripheral blood sample. Because the client
may have platelet deficiency, maintain digital pressure directly on the puncture site for 3 to 5 minutes
after the needle is withdrawn. Also, inspect the site
for excessive bruising after the procedure.
Complications and precautions: Note and report
drugs that alter platelet aggregation and discontinue if test results indicate prolonged aggregation. Report any abnormal test results to the
physician.

CLOT RETRACTION TEST
When blood collected in a test tube first clots, the
entire column of blood solidifies. As time passes, the
clot diminishes in size. Serum (the fluid remaining
after blood coagulates) is expressed, and only the red
blood cells remain in the shrunken fibrin clot.
Because platelets are necessary for this process, the
speed and extent of clot retraction roughly reflect
the adequacy of platelet function. Individuals with
thrombocytopenia or platelet dysfunction, for
example, have samples with scant serum and a soft,
plump, poorly demarcated clot.
The results of the clot retraction test should be
evaluated in relation to other hematologic, platelet,
and coagulation studies. If the client has a low hematocrit, for example, the clot is small and the volume
of serum is great. In contrast, individuals with polycythemia or hemoconcentration have poor clot
retraction because the numerous red blood cells
contained in the clot separate the fibrin strands and
interfere with normal retraction.

Reference Values
A normal clot, gently separated from the side of
the test tube and incubated at 98.6F (37C),
shrinks to about half its original size within 1
hour. The result is a firm, cylindrical fibrin clot
that contains all of the red blood cells and is
sharply demarcated from the clear serum.

INTERFERING FACTORS

Rough handling of the sample alters clot formation.
INDICATIONS FOR CLOT RETRACTION TEST

Evaluation of adequacy of platelet function
Evaluation of thrombocytopenia of unknown
etiology
Suspected antiplatelet antibodies resulting from
immune disorders or drug-antibody reactions
Suspected abnormalities of fibrinogen or fibrinolytic activity
Monitoring of response to conditions that predispose to DIC
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and approximately 5
mL of blood is collected in a red-topped tube. The
sample is promptly sent to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are essen-

SECTION I—Laboratory

TABLE 2–6

•

Tests

Causes of Positive Rumple-Leeds Capillary Fragility Test

Strongly positive (grade 4)

Aplastic anemia
Chronic renal disease
Glanzmann’s thrombasthenia
Idiopathic thrombocytopenic purpura (ITP)
Leukemia
Thrombocytopenia caused by acute infectious disease
(measles, influenza, scarlet fever)

Moderately positive (grade 3)

Hepatic cirrhosis

Slightly positive (grade 2)

Allergic and senile purpuras
Decreased estrogen levels
Deficiency of vitamin K, factor VII, fibrinogen, or prothrombin
Dysproteinemia
Polycythemia vera
von Willebrand’s disease

tially the same as for any study involving the collection of a peripheral blood sample.
Because the client may have platelet dysfunction
or deficiency, maintain digital pressure directly on
the puncture site for 3 to 5 minutes after the
needle is withdrawn.
Inspect the site for excessive bruising after the
procedure.

RUMPLE-LEEDS CAPILLARY FRAGILITY
TEST (TOURNIQUET TEST)
The capillary fragility test indicates the ability of
capillaries to resist rupturing under pressure.
Excessive capillary fragility may be caused by either
abnormalities of capillary walls or thrombocytopenia. The causes of positive test results are listed in
Table 2–6.
The test is performed by applying a blood pressure cuff inflated to 100 mm Hg to the client’s arm
for 5 minutes. The resulting petechiae in a circumscribed area are then counted.
This test is unnecessary in the presence of obvious
petechiae or large ecchymoses. It also should not be
performed on clients known to have or suspected of
having DIC.
INTERFERING FACTORS

Repetition of the test on the same extremity
within 1 week will yield inaccurate results.
INDICATIONS FOR RUMPLE-LEEDS CAPILLARY
FRAGILITY TEST (TOURNIQUET TEST)

History of “easy bruising” or production of

Reference Values
Fewer than 10 petechiae (excluding those that
may have been present before the test) in a 2inch circle is considered normal. Results may
also be reported according to the following scale,
with grade 1 indicating a normal or negative
result. Causes of positive results are listed in
Table 2–6.
Grade

Petechiae per 2-Inch Circle

0–10

10–20

20–50

petechiae by the application of a tourniquet for
venipuncture
Verification of increased capillary fragility,
although the test itself is not specific for any
particular bleeding disorder (see Table 2–6)
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The procedure, including the degree of discomfort to be expected from the inflated blood pressure cuff
Inspect the client’s forearms and select a site that
is as free as possible of petechiae. Measure an area 2
inches in diameter; the site may be circled lightly
with a felt-tipped marker if necessary for reference.

CHAPTER 2—Hemostasis

If petechiae are present in the site to be measured,
note and record the number.
THE PROCEDURE

A blood pressure cuff is applied to the arm and
inflated to 100 mm Hg. The pressure is maintained
for 5 minutes. The blood pressure cuff is then
removed and the petechiae counted and the number
recorded.
NURSING CARE AFTER THE PROCEDURE

There is no specific aftercare. If the arm feels
“tense” or “full,” it may be elevated for a few
minutes to hasten venous drainage.
Complications and precautions: Note and report
tendency for easy bruising or presence of
petechiae. Take measures to prevent trauma to the
skin and mucous membranes if results are above
the normal values.

COAGULATION STUDIES
Coagulation studies are performed to evaluate the
components and pathways of the coagulation
sequence. Innumerable tests have been devised to
diagnose inherited, acquired, and iatrogenic deficiencies of coagulation. Some of these require
specialized techniques or rare reagents available only
in laboratories that perform many such tests. Other
tests are less precisely diagnostic but more available
and more readily applicable to immediate clinical
situations. The tests included here are widely available.
Screening tests of hemostatic function include the
platelet count, bleeding time, prothrombin time,
and partial thromboplastin time. When a “coagulation profile” or “coagulogram” is ordered, it includes
the four screening tests plus clotting time and activated partial thromboplastin time.

PROTHROMBIN TIME
The prothrombin time (PT, pro time) test is used to
evaluate the extrinsic pathway of the coagulation
sequence. It represents the time required for a firm
fibrin clot to form after tissue thromboplastin (coagulation factor III) and calcium are added to the
sample. These added substances directly activate
factor X, the key factor in all three coagulation pathways (see Fig. 2–1). Neither platelets nor the factors
involved in the intrinsic pathway are necessary for
the clot to form.
To give a normal PT result, plasma must have at
least 100 mg/dL of fibrinogen (normal: 150 to 400
mg/dL) and adequate levels of factors X, VII, V, and
II (prothrombin). Because the test bypasses the clot-

and Tests of Hemostatic Functions

ting factors of the intrinsic pathway, the PT cannot
detect the two most common congenital coagulation disorders: (1) deficiency of factor VIII (hemophilia A, or “classic” hemophilia) and (2) deficiency of factor IX (hemophilia B, or Christmas
disease). Also, thrombocytopenia does not prolong
the PT.
PT measurements are reported as time in seconds
or as a percentage of normal activity, or both. Time
in seconds indicates the length of time for the blood
to clot when chemicals are added in comparison to
normal blood with the same chemicals added
(control value). A value that is higher than the
control sample is considered to be deficient in
prothrombin. Some laboratories report the results in
percentages that are derived from a plotted graph
based on dilutions of the control samples and the
time in seconds it takes for the sample to clot; the
seconds are then converted to percentages. The time
then reflects the percentage of normal clotting time
by comparing the client’s clotting time to its intersection point with the percentage on the graph.
Usually an increase in time for clotting equals a
decrease in the percentage of activity, although
different laboratories can obtain different results
when determining the percentages. This difference is
because of the different thromboplastins used as
reagents in the testing procedure.
Because the variability in responsiveness to the
different thromboplastins has resulted in dosing
differences, a thromboplastin has been developed by
the first International Reference Preparation. This
reagent is used to monitor the therapeutic levels for
coagulation during coumarin-type therapy. A standardization of reporting the PT assay test results
developed by the World Health Organization has
been adopted for this reagent. It is known as the
International Normalized Ratio (INR). The INR is
calculated with the use of a nomogram developed to
demonstrate the relationship between the INR and
the prothrombin ratios with the International
Sensitivity Index range (values associated with the
available thromboplastin reagents from the various
companies that develop them). PT evaluation can
now be based on the INR and both are reported as
PT and its equivalent INR for evaluation and decisions in oral anticoagulation therapy as endorsed
by the Committee on Antithrombotic Therapy of
the American College of Chest Physicians, the
Committee for Thrombosis and Hemostasis, and the
International Committee for Standardization in
Hematology. The recommended INR therapeutic
range for oral anticoagulant therapy is 2.0 to 3.0 in
the treatment of venous thrombosis, pulmonary
embolism, and the prevention or treatment of
systemic embolism. A pro time test system is now

SECTION I—Laboratory

Tests

Reference Values
Conventional Units
Newborns

SI Units

12–21 sec

12–21 s

Men

9.6–11.8 sec

9.6–11.8 s

Women

9.5–11.3 sec

9.5–11.3 s

2.0–3.0 sec for anticoagulation,
higher (3.0–4.5 sec) for recurrent
systemic embolization

2.0–3.0 s
3.0–4.5 s for recurrent systemic
embolization

Adults

INR

Critical values 8–9 sec below control or 40 sec

available to perform immediate measurement of PT
at the bedside using a fresh whole blood sample,
reagent cartridges, and a monitor that operates on
rechargeable batteries.
Prothrombin is a vitamin K–dependent protein
produced by the liver. Thus, any disorder that
impairs the liver’s ability to use vitamin K or to form
proteins (e.g., the various types of cirrhosis)
prolongs the PT. Anticoagulants of the coumarin
family act by inhibiting hepatic synthesis of the vitamin K–dependent factors II, VII, IX, and X. A natural anticoagulant system dependent on the action of
vitamin K on the proteins C and S is different from
the activity of this vitamin on coagulation factors II,
VII, IX, and X. Protein C acts to neutralize the activity of factors VIIIa and Va, and protein S increases
the inactivation of VIIIa and Va by the protein C.
Any deficiency of the various factors can alter the
balance between the two proteins and result in
thrombotic disorders. The tests are performed to
determine their functional activity and reveal a
tendency toward hypercoagulation and thrombosis
or to diagnose a hereditary deficiency.
Because values may vary according to the source
of the substances added to the sample and the type
of laboratory equipment used, the result is usually
evaluated in relation to a control sample obtained
from an individual with normal hemostatic function.
Test results are sometimes given as a percentage of
normal activity, comparing the client’s results
against a curve that shows the normal clotting rate of
diluted plasma. The normal value in this case is 100
percent; however, the method itself is thought to be
inaccurate because dilution affects the clotting
process.

8–9 s below control or 40 s

INTERFERING FACTORS

Numerous drugs may alter the PT results, including
the following:
Drugs that prolong the PT, such as coumarin
derivatives, quinidine, quinine, thyroid hormones,
adrenocorticotropic hormone, steroids, alcohol,
phenytoin, indomethacin, and salicylates
Drugs that may shorten the PT, such as barbiturates (especially chloral hydrate), oral contraceptives, and vitamin K31
Traumatic venipuncture may lead to erroneous
results because of activation of the coagulation
sequence.
Excessive agitation of the sample may erroneously prolong the PT.
A fibrinogen level of less than 100 mg/dL
(SI units, 1.00 g/L) (normal: 150 to 400 mg/dL
[SI units, 1.50–4.00 g/L]) may prolong the
PT.
INDICATIONS FOR PROTHROMBIN TIME

Signs of abnormal bleeding such as epistaxis, easy
bruising, bleeding gums, hematuria, and menorrhagia
Identification of individuals who may be prone to
bleeding during surgical, obstetric, dental, or
invasive diagnostic procedures
Evaluation of response to anticoagulant therapy
with coumarin derivatives and determination of
dosage required to achieve therapeutic results
Differentiation of clotting factor deficiencies of V,
VII, and X, which prolong the PT, from congenital coagulation disorders such as hemophilia A
(factor VIII) and hemophilia B (factor IX), which
do not alter the PT

CHAPTER 2—Hemostasis

Monitoring of effects on hemostasis of conditions
such as liver disease, protein deficiency, and fat
malabsorption
NURSING CARE BEFORE THE PROCEDURE

In general, client preparation is the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
Because many drugs may affect the PT result, all
medications taken by the client should be noted.
If the individual is receiving anticoagulant therapy, the time and the amount of the last dose
should be noted.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a light-blue-topped tube. Traumatic
venipunctures and excessive agitation of the sample
should be avoided.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are essentially the same as for any study involving the collection of a peripheral blood sample.
Because the client may have a coagulation deficiency, maintain digital pressure directly on the
puncture site for 3 to 5 minutes after the needle is
withdrawn.
Inspect the site for excessive bruising after the
procedure.
Bleeding episode: Note and report increase in
PT, medications taken that affect the PT and
expected test values, symptoms such as bleeding
from any area (blood in sputum, feces, urine;
bleeding from nose, skin), headache, increased
pulse, or pain in the abdomen or back. Report
changes related to administration of coumarintype medication and adjust drug dosage as
ordered until desired INR is reached. Protect
skin, mucous membranes, and organs from
trauma (shaving, brushing teeth, suctioning,
intramuscular [IM], subcutaneous [SC], and
intravenous [IV] injections, falls, activities that
are strenuous, straining). Test for occult blood
in body secretions and excretions. Inform
client to avoid drugs that potentiate the effect
of coumarin-type drugs. Instruct client in
importance and frequency of PT laboratory
testing.
Venous thrombosis: Note and report decreases
in PT or other factors predisposing to formation of venous thrombi. Provide leg exercises
and adequate fluid intake. Advise client to avoid
crossing legs, wearing constrictive clothing, or
participating in other activities that impair

and Tests of Hemostatic Functions

circulation. Inform client of importance and
frequency of PT testing.
Critical values: Notify the physician immediately of an increase of greater than 40 seconds
or 15 seconds above the control time. Prepare
the client for administration of IM vitamin K or
IV frozen plasma. Notify the physician immediately of an increase of greater than 24
seconds in individuals with a liver disease if
they are experiencing hypoprothrombinemia
from vitamin K deficiency. Notify the physician immediately if there is a decrease of less
than 8 to 9 seconds or 11 to 12 seconds below
the control time. Prepare the client for possible SC administrations of heparin.

PARTIAL THROMBOPLASTIN
TIME/ACTIVATED PARTIAL
THROMBOPLASTIN TIME
The partial thromboplastin time (PTT) test is used
to evaluate the intrinsic and common pathways of
the coagulation sequence. It represents the time
required for a firm fibrin clot to form after phospholipid reagents similar to thromboplastin reagent
are added to the specimen. Because coagulation
factor VII is not required for the PTT, the test
bypasses the extrinsic pathway (see Fig. 2–1).
To give a normal PTT result, factors XII, XI, IX,
VIII, X, V, II (prothrombin), and I (fibrinogen) must
be present in the plasma. The PTT is more sensitive
than the PT in detecting minor deficiencies of clotting factors because factor levels below 30 percent of
normal prolong the PTT.
The activated partial thromboplastin time (aPTT)
is essentially the same as the PTT but is faster and
more reliably reproducible. In this test, the thromboplastin reagent may be kaolin, celite, or ellagic
acid, all of which more rapidly activate factor XII.
It is possible to infer which factors are deficient by
comparing the results of the PTT with those of the
PT. A prolonged PTT with a normal PT points to a
deficiency of factors XII, XI, IX, and VIII and to von
Willebrand’s disease. In contrast, a normal PTT with
a prolonged PT occurs only in factor VII deficiency.32
In addition to heparin therapy and coagulation
factor deficiencies, the following also prolong the
PTT: circulating products of fibrin and fibrinogen
degradation, polycythemia, severe liver disease, vitamin K deficiency, DIC, and established therapy with
coumarin anticoagulants.
INTERFERING FACTORS

Heparin and established therapy with coumarin
derivatives alter the PTT.

SECTION I—Laboratory

Tests

Reference Values
Newborns

Time in seconds is higher up to 3 mo of age than for adults

Adults
PTT

30–45 sec

aPTT

35–45 sec*

Critical values

>20 sec more than control if not receiving heparin therapy
53 sec or >2.5 times control if receiving heparin therapy

* Values can vary among laboratories.

Traumatic venipunctures may lead to erroneous
results because of activation of the coagulation
sequence.
Excessive agitation of the sample may prolong the
PTT.
INDICATIONS FOR PTT/APTT TEST

Signs of abnormal bleeding such as epistaxis, easy
bruising, bleeding gums, hematuria, and menorrhagia
Identification of individuals who may be prone to
bleeding during surgical, obstetric, dental, or
invasive diagnostic procedures
Evaluation of responses to anticoagulant therapy
with heparin or established therapy, or both, with
coumarin derivatives and determination of
dosage required to achieve therapeutic results
Detection of congenital deficiencies in clotting
factors such as hemophilia A (factor VIII) and
hemophilia B (factor IX), which alter the PTT
Monitoring of effects on hemostasis of conditions
such as liver disease, protein deficiency, and fat
malabsorption
NURSING CARE BEFORE THE PROCEDURE

In general, client preparation is the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
If the individual is receiving anticoagulant therapy, the time and the amount of the last dose
should be noted.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a light-blue-topped tube. Traumatic
venipunctures and excessive agitation of the sample
should be avoided.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are essentially the same as for any study involving the collection of a peripheral blood sample.

Because the client may have a coagulation deficiency, maintain digital pressure directly on the
puncture site for 3 to 5 minutes after the needle is
withdrawn.
Inspect the site for excessive bruising after the
procedure.
Bleeding episode: Report increase in PTT or
aPTT during heparin therapy; note that a therapeutic range is maintained (usually 1.5 to 2.5
times the control). Note also (1) drugs taken
that can interfere with the action of heparin
therapy, (2) the administration of prophylactic
low-dose heparin that does not require PTT
testing, and (3) symptoms such as bleeding
from any area (blood in sputum, urine, feces;
bleeding from nose, skin, mucous membranes).
Adjust dosage according to physician order.
Protect from trauma to skin, mucous
membranes, organs, and joints (falls; rough
handling of extremities; shaving; brushing
teeth; IM, SC, and IV injections; suctioning).
Test for occult blood in body secretions and
excretions. Inform client to avoid drugs that
affect the PTT. Provide special considerations to
allay anxiety related to possible bleeding
tendencies.
Critical values: Notify the physician at once
of an increase of greater than 20 seconds
above the control if the individual is not
receiving heparin therapy. If heparin therapy
is administered, a PTT level of less than 53
seconds indicates an inadequate anticoagulation effect; the physician should be told
immediately if a level is greater than 2.5
times the control time level.

WHOLE BLOOD CLOTTING TIME
(COAGULATION TIME, LEE-WHITE
COAGULATION TIME)
Whole blood clotting time, also known as coagulation time (CT) or Lee-White coagulation time, is the

CHAPTER 2—Hemostasis

oldest but least accurate of the coagulation tests. It
measures the time it takes blood to clot in a test tube.
Because the sensitivity of the test is low, coagulation
problems of mild to moderate severity are not
apparent. Heparin prolongs clotting time; therefore,
the test was once used to monitor heparin therapy.
PTT or aPTT is currently used to evaluate such therapy.
Reference Values
4 to 8 minutes
Because this test is relatively insensitive and
difficult to standardize, a normal result does not
rule out a coagulation defect.

INTERFERING FACTORS

Heparin prolongs the whole blood clotting time.
Traumatic venipuncture may lead to erroneous
results.
INDICATIONS FOR WHOLE BLOOD CLOTTING
TIME TEST

Evaluation of response to heparin therapy
Adequate anticoagulation is indicated by a clotting time of about 20 minutes.
Signs of abnormal bleeding such as epistaxis, easy
bruising, bleeding gums, hematuria, and menorrhagia
Suspected congenital coagulation defect that
involves the intrinsic coagulation pathway (e.g.,
deficiencies of factors VIII, IX, XI, and XII)
NURSING CARE BEFORE THE PROCEDURE

In general, client preparation is the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
If the individual is receiving heparin anticoagulant therapy, the time and the amount of the last
dose should be noted.
THE PROCEDURE

A venipuncture is performed and 3 mL of blood
collected in a syringe and then discarded. A new
syringe, glass or plastic, is attached to the venipuncture needle, and an additional 3 mL of blood is withdrawn. Traumatic venipunctures and excessive
movement of the needle in the vein must be avoided
if accurate results are to be obtained.
As the second sample is withdrawn, timing is
begun with a stopwatch. The sample is immediately
and gently transferred into three glass tubes (1 mL in
each). The test tubes are placed in a water bath at

and Tests of Hemostatic Functions

98.6F (37C) and are tilted gently every 30 seconds
until a firm clot has formed in each tube.
Timing is completed when all tubes contain firm
clots, and the interval is recorded as the clotting
time.
NURSING CARE AFTER THE PROCEDURE

THROMBIN CLOTTING TIME
The thrombin clotting time (TCT, plasma thrombin
time) test is used to evaluate the common final pathway of the coagulation sequence. Preformed thrombin (coagulation factor IIa), usually of bovine origin,
can be added to the blood sample to convert fibrinogen (factor I) directly to a fibrin clot. Because the
test bypasses the intrinsic and extrinsic pathways,
deficiencies in either one do not affect the TCT (see
Fig. 2–1).
Thrombin-induced clotting is very rapid, and
the test result can be standardized to any desired
normal value (usually 10 to 15 seconds). The TCT is
prolonged if fibrinogen levels are below 100 mg/dL
(normal: 150 to 400 mg/dL), if the fibrinogen present is functioning abnormally, or if fibrinogen
inhibitors (e.g., streptokinase, urokinase) are present
(see below). In all of these conditions, the PT and
PTT also are prolonged.33
Reference Values
10 to 15 seconds (Values vary among laboratories.)

INTERFERING FACTORS

A fibrinogen level of less than 100 mg/dL (SI
units, 1.00 g/L) (normal: 150 to 400 mg/dL [SI
units, 1.50 to 4.00 g/L) prolongs the TCT.

SECTION I—Laboratory

Tests

Abnormally functioning fibrinogen prolongs the
TCT.
Fibrinogen inhibitors such as streptokinase and
urokinase prolong the TCT.
Traumatic venipunctures and excessive agitation
of the sample may alter results.

therapy or in those with DIC, hypoprothrombinemia, and cirrhosis.
Abnormal PCT results must be evaluated in relation to coagulation studies such as PT, PTT, and
factor assays, to differentiate platelet factor deficiencies from clotting factor deficiencies.

INDICATIONS FOR THROMBIN CLOTTING
TIME TEST

Confirmation of suspected DIC as indicated by a
prolonged TCT
Detection of hypofibrinogenemia or defective
fibrinogen
Monitoring of effects of heparin or fibrinolytic
therapy (e.g., with streptokinase)
NURSING CARE BEFORE THE PROCEDURE

A venipuncture is performed and the sample
collected in a light-blue-topped tube. Traumatic
venipunctures and excessive agitation of the sample
should be avoided.

Reference Values
Fifteen to 20 seconds with more than 80 percent
of the prothrombin consumed

INTERFERING FACTORS

Traumatic venipunctures and excessive agitation
of the sample may alter test results.
Therapy with anticoagulants may shorten the
PCT.
INDICATIONS FOR PROTHROMBIN CONSUMPTION
TIME TEST

Suspected deficiency of platelet factor 3 or of the
clotting factors involved in the intrinsic coagulation pathway (i.e., factors VIII, IX, XI, and XII), as
indicated by a shortened PCT
Suspected DIC, as indicated by a shortened PCT
Monitoring of effects on hemostasis of conditions
such as liver disease and protein deficiency

NURSING CARE AFTER THE PROCEDURE

PROTHROMBIN CONSUMPTION TIME
The prothrombin consumption time (PCT, serum
prothrombin time) test measures utilization of
prothrombin when a blood clot forms. Normally,
the formation of a clot “consumes” prothrombin
by converting it to thrombin. Individuals with
deficiencies in platelets, platelet factor 3, or
factors involved in the intrinsic coagulation pathway
(see Fig. 2–1) are not able to convert as much
prothrombin to thrombin. In such cases, excess
prothrombin remains in the serum after the clot is
formed, thus shortening the PCT. The PCT also may
be shortened in persons receiving anticoagulant

NURSING CARE BEFORE THE PROCEDURE

In general, client preparation is the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
If the client is receiving anticoagulant therapy, the
time and the amount of the last dose should be
noted.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. As with other coagulation studies, traumatic venipunctures and excessive agitation of the sample should be avoided.
NURSING CARE AFTER THE PROCEDURE

CHAPTER 2—Hemostasis

FACTOR ASSAYS
If the PT or PTT/aPTT is abnormal, but the nature
of the factor deficiency is unknown, specific coagulation factors may be measured. Factor assays
require specialized techniques not available in many
laboratories. Factor assays are used to discriminate
among mild, moderate, and severe deficiencies and

TABLE 2–7

•

and Tests of Hemostatic Functions

to follow the course of acquired factor inhibitors.
States associated with particular factor deficiencies
are presented in Table 2–7.
Factors of the extrinsic (II, V, VII, X) and intrinsic
(VIII, IX, XI, XII) coagulation pathways are usually
measured separately. The factor XIII assay is a separate test in which a blood clot is observed for 24
hours. Clot dissolution within this time indicates

States Associated with Coagulation Factor Deficiencies
States Associated with Deficiency

Factor

Synonym(s)

Congenital

Acquired

EXTRINSIC PATHWAY

Prothrombin

Hypoprothrombinemia

Vitamin K deficiency
Liver disease

Accelerator globulin (AcG),
proaccelerin, labile factor

Parahemophilia

Liver disease
Acute leukemia
Surgery

VII

Proconvertin, autoprothrombin I,
serum prothrombin conversion
accelerator (SPCA)

Factor VII deficiency

Liver disease

Vitamin K deficiency
Antibiotic therapy
X

Stuart factor, Stuart-Prower
factor, autoprothrombin III

Stuart factor deficiency

Liver disease
Vitamin K deficiency
Anticoagulants
Normal pregnancy
Disseminated intravascular
coagulation (DIC)
Hemorrhagic disease of the
newborn

INTRINSIC PATHWAY

VIII*

Antihemophilic factor (AHF), antihemophilic globulin (AHG)

Christmas factor, antihemophilic
factor B, plasma thromboplastin component (PTC), autoprothrombin II

Hemophilia A (classic
hemophilia)

Disseminated intravascular
coagulation (DIC)

von Willebrand’s disease

Fibrinolysis

Hemophilia B (Christmas
disease)

Liver disease
Vitamin K deficiency
Anticoagulants
Nephrotic syndrome

Plasma thromboplastin
antecedent (PTA)

Factor XI deficiency

Liver disease
(Continued on following page)

SECTION I—Laboratory

TABLE 2–7

Tests

•

States Associated with Coagulation Factor
Deficiencies (Continued)
States Associated with Deficiency

Factor

Synonym(s)

Congenital

Acquired
Vitamin K deficiency
Anticoagulants
Congenital heart disease

XII

Hageman factor

Hageman trait

Normal pregnancy
Nephrotic syndrome

COMMON PATHWAY

XIII

Fibrin-stabilizing factor

Factor XIII deficiency

Liver disease
Lead poisoning
Multiple myeloma
Agammaglobulinemia
Elevated fibrinogen levels
Postoperatively

* Factor VIII is increased in normal pregnancy (as is factor X) and in states of inflammation and other physiologic
stress.

severe factor XIII deficiency. The test for fibrinogen
(factor I) is discussed later.
INTERFERING FACTORS

Traumatic venipunctures and excessive agitation
of the sample may alter test results
INDICATIONS FOR FACTOR ASSAYS

Therapy with anticoagulants and other drugs
known to alter hemostasis

Prolonged PT or PTT of unknown etiology:
If the PT is prolonged but the PTT is normal,

Reference Values
Conventional Units

SI Units

Extrinsic Pathway
Factor II

70–130 mg/100 mL

0.7–1.3 U

Factor V

70–130 mg/100 mL

0.7–1.3 U

Factor VII

70–150 mg/100 mL

0.7–1.5 U

Factor X

70–130 mg/100 mL

0.7–1.3 U

Factor VIII

50–200 mg/100 mL

0.5–2.0 U

Factor IX

70–130 mg/100 mL

0.7–1.3 U

Factor XI

70–130 mg/100 mL

0.7–1.3 U

Factor XII

30–225 mg/100 mL

0.3–2.2 U

Intrinsic Pathway

Common Pathway
Factor XIII

Dissolution of a formed clot within 24 hr

Note: Normal values vary among laboratories.

CHAPTER 2—Hemostasis

factors of the extrinsic pathway are evaluated
(i.e., factors, II, V, VII, and X).
If the PTT is prolonged but the PT is normal,
factors of the intrinsic pathway are evaluated
(i.e., factors VIII, IX, XI, XII).
Monitoring of effects of disorders and drugs
known to lead to deficiencies in clotting factors
(see Table 2–7, p. 55)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
If the individual is receiving anticoagulant therapy, the time and the amount of the last dose
should be noted.
THE PROCEDURE

For assays of the factors involved in the intrinsic and
extrinsic coagulation pathways, a venipuncture is
performed and the sample collected in a light-bluetopped tube. For factor XIII assays, the sample is
collected in a red-topped tube. As with other coagulation studies, traumatic venipunctures and excessive agitation of the sample should be avoided. The
samples should be sent to the laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

and Tests of Hemostatic Functions

fibrinogen present is then extrapolated from this
value. In the immunologic technique, the degree of
reactivity between the plasma sample and antifibrinogen antibodies is measured. The assumption
underlying this method is that any plasma
constituent that reacts with antifibrinogen antibodies is, indeed, fibrinogen. Heat-precipitation tests are
based on a similar assumption that all of the material responsive to the precipitation technique is
really fibrinogen.34
Reference Values
150–450 mg/dL

INTERFERING FACTORS

Transfusions of whole blood, plasma, or fractions
within 4 weeks of the test may lead to erroneous
results.
Traumatic venipuncture and excessive agitation of
the sample may alter test results.
INDICATIONS FOR PLASMA FIBRINOGEN TEST

Confirmation of suspected DIC, as indicated by
decreased fibrinogen levels
Evaluation of congenital or acquired dysfibrinogenemias
Monitoring of hemostasis in disorders associated
with low fibrinogen levels (e.g., severe liver
diseases and cancer of the prostate, lung, or
pancreas)
Detection of elevated fibrinogen levels, which
may predispose to excessive thrombosis in
various situations (e.g., immune disorders of
connective tissue; glomerulonephritis; oral
contraceptive use; cancer of the breast, stomach,
or kidney)
NURSING CARE BEFORE THE PROCEDURE

PLASMA FIBRINOGEN
In the common final pathway, fibrinogen (factor I) is
converted to fibrin by thrombin (see Fig. 2–1).
Plasma fibrinogen studies are based on the fact that,
in normal healthy individuals, the serum should
contain no residual fibrinogen after clotting has
occurred.
Three different techniques can be used to perform
the test: (1) standard assay (classical procedure), (2)
immunologic technique, and (3) heat-precipitation
tests. In the standard assay, thrombin is added to the
blood sample to induce clotting. Because fibrinogen
is a plasma protein, the amount of protein in the
resulting clot is measured. The quantity of precursor

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
If the individual is receiving anticoagulant therapy, the time and amount of the last dose should
be noted.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a light-blue-topped tube. As with other
coagulation studies, traumatic venipunctures and
excessive agitation of the sample should be avoided.
The sample should be sent to the laboratory immediately.

SECTION I—Laboratory

Tests

NURSING CARE AFTER THE PROCEDURE

FIBRIN SPLIT PRODUCTS
After a fibrin clot has formed, the fibrinolytic system
acts to prevent excessive clotting. In this system,
plasmin digests fibrin. Fibrinogen also may be
degraded if there is a disproportion among plasmin,
fibrin, and fibrinogen. The substances that result
from this degradation—fibrin split products (FSP)
or fibrinogen degradation products (FDP)—interfere with normal coagulation and with formation of
the hemostatic platelet plug.
Normally, FSP are removed from the circulation
by the liver and the reticuloendothelial system. In
situations such as widespread bleeding or DIC,
however, FSP are found in the serum.
Tests for FSP are performed on serum using
immunologic techniques. Because FSP do not coagulate, they remain in the serum after fibrinogen is
removed through clot formation. Antifibrinogen
antibodies are added to the serum to detect the presence of FSP. Because normal serum contains neither
FSP nor fibrinogen, there should be nothing present
to react with the antibodies. If a reaction occurs, FSP
are present.35
Reference Values
2 to 10 mg/mL

INTERFERING FACTORS

Heparin, fibrinolytic drugs such as streptokinase
and urokinase, and large doses of barbiturates
may produce elevated levels of FSP.
Traumatic venipunctures and excessive agitation
of the sample may alter test results.
INDICATIONS FOR FIBRIN SPLIT PRODUCTS TEST

Confirmation of suspected DIC, as indicated by
elevated FSP levels
Evaluation of response to therapy with fibrinolytic drugs

Monitoring of effects on hemostasis of trauma,
extensive surgery, obstetric complications, and
disorders such as liver disease
NURSING CARE BEFORE THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube or in a special tube
provided for the FSP test by the laboratory. As with
other coagulation studies, traumatic venipunctures
and excessive agitation of the sample should be
avoided. The sample should be sent to the laboratory
promptly.
NURSING CARE AFTER THE PROCEDURE

EUGLOBULIN LYSIS TIME
The euglobulin lysis time test is used to document
excessive fibrinolytic activity. Euglobulins are
proteins that precipitate from acidified dilute
plasma; these include fibrinogen, plasminogen, and
plasminogen activator but very little antiplasmin
activity. In euglobulins prepared from normal
blood, the initial clot dissolves in 2 to 6 hours. With
excessive fibrinolytic activity, a clot forms if thrombin is added to the sample.
Shortened euglobulin lysis times are seen in fibrinolytic therapy with streptokinase or urokinase,
prostatic cancer, severe liver disease, extensive vascular trauma or surgery, and shock.
Reference Values
Lysis in 2 to 6 hours
INTERFERING FACTORS

Decreased fibrinogen levels may lead to falsely

CHAPTER 2—Hemostasis

shortened lysis time because of the reduced
amount of fibrin to be lysed.36
Traumatic venipunctures and excessive agitation
of the sample may alter results.
INDICATIONS FOR EUGLOBULIN LYSIS TIME TEST

Suspected abnormal fibrinolytic activity as indicated by lysis of the clot within about 1 hour
Differentiation of primary fibrinolysis from DIC,
which usually presents with a normal euglobulin
lysis time
Monitoring of effects of fibrinolytic therapy on
normal coagulation
NURSING CARE BEFORE THE PROCEDURE

A venipuncture is performed and the sample
collected in a light-blue-topped tube. As with other
coagulation studies, traumatic venipuncture and
excessive agitation of the sample should be avoided.
The sample should be sent to the laboratory
promptly.
NURSING CARE AFTER THE PROCEDURE

and Tests of Hemostatic Functions

Inspect the site for excessive bruising after the
procedure.
Clot lysis: Note and report decreases in lysis level
during fibrinolytic therapy. Monitor client
response and effect of therapy on coagulation.
REFERENCES
1. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, pp 182–183.
2. Ibid, p 185.
3. Ibid, p 185.
4. Ibid, p 190.
5. Porth, CM: Pathophysiology: Concepts of Altered Health States, ed
5. JB Lippincott, Philadelphia,1998, p 122.
6. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed 4.
JB Lippincott, Philadelphia, 1992, p 95.
7. Ibid, p 118.
8. Porth, op cit.
9. Ibid, p 121.
10. Sacher and McPherson, op cit, pp 192–193.
11. Ibid, p 195.
12. Ibid, p 195.
13. Ibid, p 196.
14. Fischbach, op cit, p 98.
15. Sacher and McPherson, op cit, p 197.
16. Porth, op cit, p 121.
17. Sacher and McPherson, op cit, p 182.
18. Ibid, p 182.
19. Porth, op cit, p 121.
20. Porth, op cit, p 126.
21. Sacher and McPherson, op cit, p 187.
22. Fischbach, op cit, pp 125–126.
23. Porth, op cit, p 126.
24. Sacher and McPherson, op cit, p 190.
25. Ibid, p 190.
26. Ibid, p 190.
27. Ibid, pp 188–189.
28. Ibid, p 189.
29. Ibid, p 187.
30. Ibid, pp 187–188.
31. Ibid, p 193.
32. Ibid, p 201.
33. Ibid, p 200.
34. Ibid, p 200.
35. Ibid, pp 139–140.
36. Ibid, p 203.

CHAPTER

Immunology and
Immunologic Testing
TESTS COVERED
T- and B-Lymphocyte Assays, 62
Immunoblast Transformation Tests, 66
Immunoglobulin Assays, 68
Serum Complement Assays, 71
Immune Complex Assays, 73
Radioallergosorbent Test for IgE, 73
Autoantibody Tests, 74
Fungal Infection Antibody Tests, 78
Staphylococcal Tests, 80
Streptococcal Tests, 81
Febrile/Cold Agglutinin Tests, 82
Fluorescent Treponemal AntibodyAbsorption Test, 83

INTRODUCTION

Venereal Disease Research
Laboratory and Rapid Plasma Reagin
Tests, 84
Viral Infection Antibody Tests, 85
Infectious Mononucleosis Tests, 85
Hepatitis Tests, 87
Acquired Immunodeficiency Syndrome
Tests, 88
Serum -Fetoprotein Test, 90
Carcinoembryonic Antigen Test, 92
CA 15-3, CA 19-9, CA 50, and CA 125
Antigen Tests, 93

The immune system protects the body from invasion by foreign elements
ranging from microorganisms and pollens to transplanted organs and subtly altered autologous proteins. An antigen is any substance that elicits an immune response in an immunocompetent host to whom that substance is foreign.
The cells responsible for immune reactivity are lymphocytes and macrophages. The primary
function of the lymphocytes is to react with antigens and thus initiate immune responses.
There are two main categories of immune response: (1) the cell-mediated response, produced
by locally active T lymphocytes present at the same time and place as the specific antigen, and
(2) the humoral response, the manufacture by B lymphocytes of antibody proteins that enter
body fluids for widespread distribution throughout the body.1
The immune system also removes damaged or worn-out cells and destroys abnormal cells as
they develop in the body. The cells responsible for these functions are the macrophages, which
engulf particulate debris (phagocytosis) and also secrete a vast array of enzymes, enzyme
inhibitors, oxidizing agents, chemotactic agents, bioactive lipids (prostaglandins and related
substances), complement components, and products that stimulate or inhibit multiplication of
other cells. These phagocytic and secretory activities help mediate responses to immune stimulation. Macrophages also are critically important in the induction of immunity. Only after
macrophages process antigen and present it to lymphocytes can immunologic reactivity
develop.

CHAPTER 3—Immunology

and Immunologic Testing

Laboratory tests can demonstrate with remarkable sensitivity many of the body’s immune
activities. In general, quantification of cellular components, the presence and activities of antibodies and antigens, and measurement of biologically active secretions constitute the laboratory tests of immune functions.

TESTS OF LYMPHOCYTE
FUNCTIONS
Lymphocytes, the second most numerous of the
several types of white cells in the peripheral blood
(see Table 1–4), are essential components of the
immune system. Diseases affecting lymphocytes
frequently manifest as an inability to protect the individual against environmental pathogens (immune
deficiency disorders) or as the development of
immune reactions to the individual’s own cells.2
The lymphocytes in the circulation represent only
a small fraction of the total body pool of these cells.
The majority are located in the spleen, lymph nodes,
and other organized lymphatic tissues. The lymphocytes in the blood are able to enter and leave the
circulation freely. Thus, the movement of cells from
one area or compartment to another is continuous.
Despite this process, the number of lymphocytes in
the blood and tissues is kept quite constant.
Lymphocytes have been divided into two major categories based on their immunologic activity: T
lymphocytes and B lymphocytes. There also is a
third group of lymphocytes that lack the characteristics of either T or B cells; they are called null cells.3
T lymphocytes are primarily responsible for cellmediated immunity, which requires direct cell
contact between the antigen and the lymphocyte.
This immune reaction occurs at the local site and
generally develops slowly. Examples of cell-mediated
immune responses include reactions against intracellular pathogens such as bacteria, viruses, fungi,
and protozoa; positive tuberculin skin test results;
contact dermatitis; transplant rejection (acute and
chronic reactions); and tumor immunity.
As with other blood cells, T lymphocytes develop
from stem cells (see Fig. 1–2) and then migrate to the
thymus, where they proliferate and mature.
Thymopoiesis is, however, an ineffective process, and
many T lymphocytes die either within the thymus or
shortly after leaving it. Only a small portion of the T
lymphocytes reaches the peripheral tissues as mature
T cells capable of effecting cell-mediated immunity.4
Note that the thymus functions primarily during
fetal life. The peripheral T-lymphoid system is fully
developed at birth and normally does not require a
constant input of new cells for maintenance after
birth. Thus, it is possible to surgically remove the

thymus (e.g., as is done to treat myasthenia gravis)
without impairing the individual’s cell-mediated
immune system. In contrast, failure of the thymus to
develop during fetal life leads to a severe defect in
cellular immunity (Di George’s syndrome), usually
resulting in death during infancy as a consequence
of repeated infections.5
Two subsets of T lymphocytes have been identified: helper T cells and suppressor T cells. Helper T
cells promote the proliferation of T lymphocytes,
stimulate B-lymphocyte reactivity, and activate
macrophages, thereby increasing their bactericidal
and cytotoxic functions. Suppressor T cells limit the
magnitude of the immune response. In normal individuals, there is a balance between helper and
suppressor activities. Many immune diseases are
associated with deficiencies or excesses of the Tlymphocyte subtypes (Fig. 3–1).6
The B lymphocytes are responsible for humoral
immunity through the production of circulating
antibodies. Examples of humoral immunity include
elimination of encapsulated bacteria, neutralization
of soluble toxins, protection against viruses, transplant rejection (hyperacute reaction), and possible

Figure 3–1. In normal, healthy individuals, there is a
balance between helper and suppressor activities.
Many immunodeficiency syndromes appear to be
caused by a disturbance of this balance such that a
state of unresponsiveness is created. This could result
from either a lack of helper activity or an excess of
suppressor activity. Conversely, autoimmunity, which
results from aberrant responses directed at the host’s
own antigens, could result from abnormal immunoregulation from either excessive helper or reduced
suppressor activities. (From Boggs, DR, and
Winkelstein, A: White Cell Manual, ed 4. FA Davis,
Philadelphia, 1983, p 71, with permission.)

SECTION I—Laboratory

Tests

tumor immunity. Pathological alterations in antibody production are responsible for disorders such
as autoimmune hemolytic anemia, immune thrombocytopenia, allergic responses, some forms of
glomerulonephritis and vasculitis, and transfusion
reactions.7
Actual production of antibodies (immunoglobulins) occurs in plasma cells, the most differentiated
form of B lymphocyte. All B lymphocytes have
immunoglobulins (Ig) on their surfaces. These serve
as receptors for specific antibodies. Five classes of
immunoglobulins are currently identified: IgG, IgM,
IgA, IgD, and IgE. Immune activation requires interaction not only of surface Ig with the specific antigen
but also of B lymphocytes with the helper T cells.
The activated B lymphocytes undergo transformation into immunoblasts that replicate and then
differentiate into either plasma cells, which produce
antibodies, or memory cells (“small lymphocytes”),
which retain the ability to recognize the antigen.
Similar memory cells have been found in the Tlymphocyte system.8
The relationships between the T-lymphocyte and
B-lymphocyte systems are diagrammed in Figure
3–2. In both cellular and humoral immune
responses, initial exposure to specific antigens initiates the primary immune response. Depending on
the nature and quantity of the antigen, it may take
days, weeks, or months for the cells to recognize and
respond to the antigen. Subsequent exposure to the
same antigen, however, elicits the secondary
(anamnestic) response much more rapidly than the
primary response.9
Tests of lymphocyte functions include T- and B-

lymphocyte assays, immunoblast transformation
tests, and immunoglobulin assays.

T- AND B-LYMPHOCYTE ASSAYS
T- and B-lymphocyte assays are used to diagnose a
number of immunologic disorders (Tables 3–1 and
3–2). A variety of methods are used. The most
common way to assess T-cell activity is to measure
the individual’s response to delayed hypersensitivity
skin tests. This involves intradermal injection of
minute amounts of several antigens to which the
individual has previously been sensitized (e.g.,
tuberculin, mumps, Candida). Erythema and
induration should occur at the site within 24 to 48
hours. Absence of response is termed anergy and,
thus, the test is frequently called an anergy panel.
Anergy to skin tests reflects either a temporary or a
permanent failure of cell-mediated immunity.10
Other measures of T and B lymphocytes involve
determination of the number of cell types present. T
lymphocytes are recognized by their ability to form
rosettes with sheep erythrocytes (i.e., the sheep red
cells surround the T lymphocyte). Although the
sheep erythrocytes adhere to the cell membranes of
the T lymphocytes, they react to neither B lymphocytes nor null cells.11
T lymphocytes and their subsets also can be
distinguished by their ability to react with various
monoclonal antibodies. Monoclonal antibodies
constitute a single species of immunoglobulins with
specificity for a single antigen and are produced
by immunizing mice with specific antigens. The
most commonly used monoclonal antibodies to T

Figure 3–2. The relationship between the T-lymphocyte and B-lymphocyte systems. (From Winkelstein, A, et al:
White Cell Manual, ed 5. FA Davis, Philadelphia,1998, with permission.)

CHAPTER 3—Immunology

•

TABLE 3–1

and Immunologic Testing

Causes of Altered Levels of T and B Lymphocytes

Increased Levels

Decreased Levels
T LYMPHOCYTES

Acute lymphocytic leukemia

Di George’s syndrome

Multiple myeloma

Chronic lymphocytic leukemia

Infectious mononucleosis

Acquired immunodeficiency syndrome (AIDS)

Graves’ disease

Hodgkin’s disease
Nezelof syndrome
Wiskott-Aldrich syndrome
Waldenström’s macroglobulinemia
Severe combined immunodeficiency disease (SCID)
Long-term therapy with immunosuppressive drugs
B LYMPHOCYTES

Chronic lymphocytic leukemia

Acute lymphocytic leukemia

Multiple myeloma

X-linked agammaglobulinemia

Di George’s syndrome

SCID

Waldenström’s macroglobulinemia
Acute lupus erythematosus

TABLE 3–2

•

Disorders Associated with Abnormal T-Cell Subsets
IMMUNE DEFICIENCY DISEASES (HELPER AND/OR SUPPRESSOR ACTIVITY)

Common variable hypogammaglobulinemia
Acute viral infections (infectious mononucleosis, cytomegalic inclusion disease)
Chronic graft-versus-host disease
Multiple myeloma
Chronic lymphomocytic leukemia
Primary biliary cirrhosis
Sarcoidosis
Immunosuppressive drugs (azathioprine, corticosteroids, cyclosporin A)
Acquired immunodeficiency syndrome (AIDS)
AUTOIMMUNITY (HELPER AND/OR SUPPRESSOR ACTIVITY)

Connective tissue diseases (e.g., systemic lupus erythematosus)
Acute graft-versus-host disease
Autoimmune hemolytic anemia
Multiple sclerosis
Myasthenia gravis
Inflammatory bowel diseases
Atopic eczema
Adapted from Boggs, DR, and Winkelstein, A: White Cell Manual, ed 4. FA Davis, Philadelphia, 1983, p 72.

SECTION I—Laboratory

Tests

lymphocytes are designated T3, T4, and T8. T3 is a
pan-T-cell antibody that reacts with a determinant
that is present on all mature peripheral T lymphocytes and can, therefore, be used to enumerate the
total number of T cells present. T4 antibodies identify helper T cells, and T8 antibodies identify
suppressor T cells.12
Other monoclonal antibodies include T10, T9,
and T6. T10 and T9 antibodies react with very
immature T lymphocytes (thymocytes) that are
found in the thymus gland but not in the peripheral
circulation. T10 antigen also is seen in mature
thymocytes that are localized primarily in the
medullary regions of the thymus. T6 antibodies also
react with certain immature thymocytes. As T
lymphocytes mature, reactivity to T6 antibodies is
lost. Tests involving reactivity to immature T
lymphocytes are useful in diagnosing T-cell
leukemias and lymphomas.13
B lymphocytes are detected by immunofluorescent techniques. Such techniques involve mixing
lymphocyte suspensions with heterologous antisera
to immunoglobulins that have been labeled with a
dye such as fluorescein. The antisera combine with B
lymphocytes and when the suspension is examined
by fluorescent microscopy, only B lymphocytes
appear.14
T and B lymphocytes can be differentiated by
electron microscopy, because T cells are smooth and
B cells have surface projections. This technique is
not, however, available in many laboratories.
INDICATIONS FOR T- AND B-LYMPHOCYTE
ASSAYS

Diagnosis of disorders associated with abnormal
levels of T and B lymphocytes (see Table 3–1)
Diagnosis of disorders associated with abnormal
T-cell subtypes (see Table 3–2)
Support for diagnosing acquired immunodeficiency syndrome (AIDS), as indicated by
decreased helper T cells, normal or increased

suppressor T cells, and a decreased ratio of helper
to suppressor T cells
Diagnosis of severe combined immunodeficiency
disease (SCID), an inherited disorder characterized by failure of the stem cell to differentiate into
T and B lymphocytes (Fig. 3–3)
Diagnosis of Di George’s syndrome, characterized
by failure of the thymus (and parathyroids) to
develop, with a resulting decrease in T lymphocytes (see Fig. 3–3)
Diagnosis of X-linked agammaglobulinemia,
characterized by severe B-lymphocyte deficiency
(see Fig. 3–3)
Diagnosis of common variable hypogammaglobulinemia (CVH), characterized by absent,
decreased, or defective B cells and most
commonly caused by either lack of helper T
lymphocytes or abnormal suppressor T cells (see
Fig. 3–3)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a green-topped tube or other type of
blood collection tube, depending on laboratory
preference.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Because the client may be immunosuppressed,
assess the site for signs of infection.
Complications and precautions for compromised immune status: Note and report helper Tcell level and relation to suppressor T-cell level or
decreased B cells. Administer chemotherapy or

Reference Values
T lymphocytes

60–80% of circulating lymphocytes*

B lymphocytes

10–20% of circulating lymphocytes

Null cells

5–20% of circulating lymphocytes

Helper T lymphocytes

50–65% of circulating T lymphocytes

Suppressor T lymphocytes

20–35% of circulating T lymphocytes

Ratio of helper to suppressor T lymphocytes 2:1
* A decreased lymphocyte count (lymphopenia) usually indicates a decrease in the number of circulating T lymphocytes.

CHAPTER 3—Immunology

TABLE 3–3

•

and Immunologic Testing

Immunoglobulins
Causes of Altered Levels

Class
IgG

Locations

Functions

Increased

Decreased

Plasma

Produces antibodies
against bacteria,
viruses, and toxins

Infections—all types,
acute and chronic

Lymphocytic leukemia

Interstitial fluid

Protects neonate

Starvation

Agammaglobulinemia

Placenta

Activates the complement system

Liver disease

Amyloidosis

Is a major factor in
secondary (anamnestic) response

Rheumatic fever

Toxemia of pregnancy

Sarcoidosis
IgG myelomas
IgA

Respiratory tract

Protects mucous
membranes from
viruses and bacteria

Autoimmune disease

Lymphocytic leukemia

Gastrointestinal
tract

Includes antitoxins,
antibacterial agglutinins, antinuclear
antibodies, and allergic reagins

Chronic infections

Agammaglobulinemia

Liver disease

Malignancies

Activates complement
through the alternative pathway

Wiskott-Aldrich
syndrome

Hereditary ataxia-telangiectasia

IgA myeloma

Hypogammaglobulinemia

Genitourinary
tract
Tears

Saliva
Milk, colostrum

Malabsorption syndromes

Exocrine secretions
IgM

—

Primary responder to
antigens

Lymphosarcoma

Lymphocytic leukemia

Produces antibody
against rheumatoid
factors, gram-negative organisms, and
the ABO blood group

Brucellosis, actinomycosis

Agammaglobulinemia

Trypanosomiasis

Amyloidosis

Relapsing fever

IgG and IgA myeloma

Activates the complement system

Malaria

Dysgammaglobulinemia

Infectious mononucleosis
Rubella virus in
newborn
Waldenström’s
macroglobulinemia
IgD

Serum
Cord blood

Unknown

Chronic infections

—

IgD myelomas
(Continued on following page)

SECTION I—Laboratory

Tests

TABLE 3–3

•

Immunoglobulins (Continued)
Causes of Altered Levels

Class
IgE

Locations

Functions

Increased

Decreased
Congenital agammaglobulinemia

Serum

Allergic reactions

Atopic skin disorders

Interstitial fluid

Anaphylaxis

Hay fever

Protects against parasitic worm infestations

Asthma

Anaphylaxis
IgE myeloma

other ordered medications. Provide reverse
protective precautions to prevent infection.

IMMUNOBLAST TRANSFORMATION
TESTS
When responding to a specific antigen, mature
lymphocytes undergo a series of morphological and
biochemical changes that enable them to become
actively proliferating cells (immunoblasts). The
lymphocytes enlarge, synthesize new nucleic acids
and proteins, and undergo a series of mitoses. This
proliferative expansion increases the pool of anti-

gen-responsive cells (Fig. 3–4).15 Immunoblast
transformation tests evaluate the capability of
lymphocytes to change to proliferative cells and,
thus, to respond normally to antigenic challenge.
Several methods of performing immunoblast
transformation tests can be used. Nonimmune
transformation tests involve exposing a sample of
the client’s lymphocytes to mitogens, agents that
cause normally responsive lymphocytes to become
immunoblasts independent of any antigenic effect.
Effective mitogens include plant extracts such as
phytohemagglutinin (PHA), concanavalin A (conA),
and pokeweed mitogen. PHA and conA stimulate

Figure 3–3. Several immunodeficiency diseases can be viewed as cellular blocks in the normal maturation of
lymphocytes. (From Winkelstein, A, et al: White Cell Manual, ed 5. FA Davis, Philadelphia, 1998, p 103, with permission.)

CHAPTER 3—Immunology

and Immunologic Testing

Figure 3–4. Responses of mature lymphocytes to antigens. In both the T- and B-cell systems, stimulated cells
undergo a redifferentiation process leading to immature-appearing lymphoblasts. (From Winkelstein, A, et al: White
Cell Manual, ed 5. FA Davis, Philadelphia, 1998, p 83, with permission.)

Reference Values
Nonimmune transformation tests

A stimulation index of greater than 10 indicates
immunocompetence.

Antigen-specific transformation tests

A stimulation index of greater than 3 indicates prior
exposure to the antigen.

Mixed lymphocyte culture

Nonresponsiveness indicates good histocompatibility.

primarily T lymphocytes; pokeweed stimulates both
T and B lymphocytes, although the effect on B
lymphocytes is greater. Approximately 72 hours after
the lymphocytes have been incubated with the mitogens, radiolabeled thymidine is added and then
incorporated into the deoxyribonucleic acid (DNA)
of the proliferating cells. The rate of uptake of
radioactive thymidine indicates the extent of
lymphocyte proliferation.16
After immune capability has been established,
antigen-specific transformation tests can demonstrate whether the person’s T cells have encountered
specific antigens; that is, an individual’s cellmediated immunities can be documented by
observing the way T cells respond to a battery of
known antigens (e.g., soluble viral or bacterial antigens or tissue antigens of human white cells from
organ donors).
The mixed lymphocyte culture (MLC) technique
is widely used in testing before organ transplantation. This test is based on the fact that cultured
lymphocytes can recognize and respond to foreign
antigens that have not previously sensitized the host.
Immunologically responsive lymphocytes cultured

together with cells possessing unfamiliar or
unknown surface antigens gradually develop sensitivity; after a lag period of 48 to 72 hours, the
responding cells undergo immunoblast transformation if the stimulating cells possess antigens different
from those of the host.17
INTERFERING FACTORS

Radioisotope studies performed within 1 week of
the test may alter test results.
Pregnancy or oral contraceptive use may lead to a
decreased response to PHA in nonimmune transformation tests.
INDICATIONS FOR IMMUNOBLAST
TRANSFORMATION TESTS

Support for diagnosing immunodeficiency disorders as indicated by a decreased response to
nonimmune transformation tests
Identification of microorganisms to which the
individual was previously exposed as indicated by
an increased response to antigen-specific transformation tests
Support for identifying compatible organ donors

SECTION I—Laboratory

Tests

and recipients as indicated by nonresponsiveness
on mixed lymphocyte culture
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
All clients should be interviewed to determine
whether they have undergone any radioisotope
tests within the past week; if the client is a woman,
it should be determined whether she is pregnant
or using oral contraceptives.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a green-topped tube or other type of
blood collection tube, depending on laboratory
preference. The sample should be transported to the
laboratory promptly.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Because the client may be immunosuppressed,
assess the site for signs of infection.
Complications and precautions: Note and report
the lymphocyte response to an antigenic challenge
in relation to signs and symptoms of tissue rejection or allergic condition.

IMMUNOGLOBULIN ASSAYS
Immunoglobulins are serum antibodies produced
by the plasma cells of the B lymphocytes.
Immunoglobulins (Ig) have been subdivided into
the five classes: IgG, IgA, IgM, IgD, and IgE. Their
functions are listed in Table 3–3. IgG, IgA, and IgM
have been further divided into subclasses: IgG1,
IgG2, IgG3, and IgG4.
Four techniques can be used to assess Ig: (1)
serum protein electrophoresis, (2) immunoelectrophoresis, (3) radial immunodiffusion, and (4)
radioimmunoassay. Serum protein electrophoresis,
although not specific to the immunoglobulins, may
indicate the presence of immunologic disorders such
that additional testing may not be needed.
Electrophoresis separates the serum proteins into
albumin and globulin components, with the latter
being further broken down into 1, 2, , and
fractions. Most of the fraction derives from IgG
molecules, whereas IgM contributes to the
portion.18
Three types of alterations in immunoglobulins

can be identified by serum protein electrophoresis:
(1) hypogammaglobulinemia, a reduction in the
total quantity of immunoglobulins; (2) monoclonal
gammopathy, excessive amounts of single immunoglobulins or proteins related to immunoglobulins
(seen in multiple myeloma and macroglobulinemia); and (3) polyclonal gammopathy, excessive
amounts of several different immunoglobulins (seen
in many infections and diffuse inflammatory conditions).19,20 Examples of these serum protein electrophoretic patterns are diagrammed in Figure 3–5.
Additional examples of disorders associated with
monoclonal and polyclonal gammopathies are listed
in Table 3–4.
Immunoelectrophoresis is not a quantitative
technique, but it provides such detailed separation
of the individual immunoglobulins that modest
deficiencies are readily detected. It identifies the
presence of monoclonal protein and its type. Radial
immunodiffusion allows measurement of the quantity of individual immunoglobulins to concentrations as low as 10 to 20 mg/dL. Radioimmunoassay
provides better results when immunoglobulin levels
are below 20 mg/dL. Serum IgD and IgE are
normally well below this level, as are immunoglobulin levels in most body fluids other than serum.
Cryoglobulin is an immunoglobulin that
precipitates in the cold and, in those who develop
high concentrations, causes the blockage of small
capillaries in fingers, ears, and toes exposed to
cold temperatures. The test is performed by first
cooling the blood serum in a refrigerator to note
whether a precipitate forms in 2 to 7 days and
then measuring the volume in relation to the
percentage of the total serum to obtain a numerical
value analogous to a hematocrit. Three positive
types of cryoglobulins can be identified by immunoelectrophoresis. Pyroglobulin is a protein identified
by heating the blood serum to obtain a precipitate,
indicating an abnormality. The test is performed to
determine cold sensitivity as well as to assist in the
diagnosis of collagen disorders, malignancies, or
infections.21
INTERFERING FACTORS

Immunizations within 6 months before the test
may alter test results.
Transfusions of either whole blood or fractions
within 2 months may alter test results.
INDICATIONS FOR IMMUNOGLOBULIN ASSAYS

Suspected immunodeficiency, either congenital or
acquired
Suspected immunoproliferative disorders such as

CHAPTER 3—Immunology

and Immunologic Testing

Figure 3–5. Serum protein electrophoretic patterns. (From Winkelstein, A, et al: White Cell Manual, ed 5. FA Davis,
Philadelphia, 1998, p 95, with permission.)

multiple myeloma or Waldenström’s macroglobulinemia
Suspected autoimmune disorder
Suspected malignancy involving the lymphoreticular system

Monitoring of effects of chemotherapy or radiation therapy, or both, which may suppress the
immune system
Identification of hypogammaglobulinemia,
monoclonal gammopathy, and polyclonal

Image/Text rights unavailable

SECTION I—Laboratory

Tests

Reference Values
Percentage of Total Protein
Serum Protein Electrophoresis

Conventional Units

SI Units

Constituent
Albumin

52–68

0.520–0.680

Globulin

32–48

0.320–0.480

1-Globulin

2.4–5.3

0.024–0.053

2-Globulin

6.6–13.5

0.066–0.135

-Globulin

8.5–14.5

0.085–0.145

-Globulin

10.7–21.0

0.107–0.210

Immunoglobulins
Neonates
SI Units
6 mo
SI Units
1 yr
SI Units
6 yr
SI Units
12 yr
SI Units
16 yr
SI Units
Adults
SI Units
Percentage of total
immunoglobulins
in adults

IgG, mg/dL

IgA, mg/dL

IgM, mg/dL

IgD, mg/dL

IgE, mg/dL

650–1250

0–12

5–30

—

6.5–12.5 g/L

0.00–0.12 g/L

0.05–0.30 g/L

200–1100

10–90

10–80

—

2.0–11.0 g/L

0.10–0.90 g/L

0.10–0.80 g/L

300–1400

20–150

20–100

—

3.0–14.0 g/L

0.20–1.50 g/L

0.20–1.0 g/L

550–1500

50–175

22–100

—

5.50–15.0 g/L

0.50–1.75 g/L

0.22–1.0 g/L

660–1450

50–200

30–120

—

6.60–14.5 g/L

0.50–2.0 g/L

0.30–1.20 g/L

700–1050

7–225

35–75

—

7.0–10.5 g/L

0.70–2.25 g/L

0.35–0.75 g/L

800–1800

100–400

55–150

0.5–3

0.01–0.04

8.0–18.0 g/L

1.0–4.0 g/L

0.55–1.50 g/L

0.005–0.03 g/L

0–430 mg/L

75–80%

15%

10%

0.2%

0.0002%

gammopathy by serum protein electrophoresis
(see Fig. 3–5 and Table 3–4)
Support for diagnosing a variety of disorders
associated with altered immunoglobulin levels
(see Table 3–3)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
The client should be interviewed to determine

whether he or she has received immunizations
within 6 months before the test or transfusions of
whole blood or fractions within 2 months before
the test.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube or other type of blood
collection tube, depending on laboratory preference.
The sample should be transported to the laboratory
promptly.

CHAPTER 3—Immunology

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Because the client may be immunosuppressed,
assess the site for signs of infection.
Complications and precautions: Note and report
abnormal levels in relation to immunodeficiency,
malignant, or autoimmune disorders.

TESTS OF THE COMPLEMENT
SYSTEM
Complement is a system of protein molecules, the
sequential interactions of which produce biologic
effects on surface membranes, on cellular behavior,
and on the interactions of other proteins. Each of
the proteins of the complement system is inactive by
itself. Activation occurs through a cascadelike
sequence after contact with substances such as IgG
or IgM antigen-antibody complexes, aggregated IgA,
certain naturally occurring polysaccharides and
lipopolysaccharides, activation products of the coagulation system, and bacterial endotoxins. Activation
of the complement system results in an inflammatory response that destroys or damages cells.
Complement proteins are identified by letters and
numbers and are listed here in order of activation in
the “classical pathway” of the complement cascade:
C1q, C1r, C1s, C4, C2, C3, and then C5 through C9.
The “alternate pathway” bypasses C1, C4, and C2
activation and begins directly with C3. The key step
in the alternate pathway is activation of properdin, a
serum protein without biologic effects in its inactive
form. Contact with aggregated IgA, with bacterial
endotoxins, or with complex molecules such as
dextran, agar, and zymosan alters properdin and
initiates the sequence at C3.22
Complete activation to C9 leads to membrane
disruption and irreversible cell damage. Along the
way to complete activation, the following activities
occur: C2 releases a low-molecular-weight peptide
with kinin activity. Activation of products of C3 and
C5 affects mast cells, smooth muscle, and leukocytes
to produce an anaphylactic effect; other elements of
C3 and C5 bind to cell membranes and render them
more susceptible to phagocytosis, a process called
opsonization. Fragments of C3 and C4 cause
immune adherence, in which complement-coated
particles bind to cells with surface membranes that
have complement receptors; activated C3 and C4 are
also capable of virus neutralization. C3 and C5 exert
chemotactic activity on neutrophils, and the C5 to
C9 complex influences the procoagulant activity of

and Immunologic Testing

platelets. Conversely, procoagulant factor XII can
initiate C1 activation, and plasmin (the substance
that dissolves fibrin) and thrombin (which converts
fibrinogen to fibrin) can cleave C3 into its active
form.23

SERUM COMPLEMENT ASSAYS
Radioimmunoassay and immunodiffusion techniques have made it possible to quantify each of the
complement components. For clinical purposes,
however, only total complement, C3, and C4 are
measured. Total complement (CH50), also known as
a hemolytic assay, is measured by exposing a sample
of human serum to sheep red cells coated with
complement-requiring antibody. Results are
expressed as CH50 units, reflecting the dilution at
which adequate complement exists to lyse one-half
of the test cells. C3 and C4 levels are measured individually by radial immunodiffusion. These latter
tests take 24 to 36 hours to complete, and results are
easily affected by improper handling of the specimen.24
The causes of alterations in C3 and C4 levels are
presented in Table 3–5.
INTERFERING FACTORS

Failure to transport the sample to the laboratory
immediately may alter test results because
complement deteriorates rapidly at room temperature.
Hemolysis of the sample may alter test results.
INDICATIONS FOR SERUM COMPLEMENT ASSAYS

Suspected acute inflammatory disorder as generally indicated by elevated total complement levels
Suspected immune or infectious disorder (e.g.,
acute glomerulonephritis, systemic lupus erythematosus [SLE], rheumatoid arthritis, hepatitis,
subacute bacterial endocarditis, gram-negative
sepsis) or both, as indicated by decreased total
complement levels
Support for diagnosing hereditary deficiencies of
complement components as indicated by
decreased levels of total complement or of specific
components such as C3 and C4, or of both (see
Table 3–5)
Support for diagnosing cancer, especially that of
the breast, lung, digestive system, cervix, ovary,
and bladder, as indicated by increased levels of C3
and C4 (see Table 3–5)
Monitoring for the progression of malignant
disease as indicated by declining complement
levels as the disease progresses
Support for diagnosing a variety of immune and

SECTION I—Laboratory

TABLE 3–5
Component

Tests

•

Causes of Alterations in C3 and C4 Levels

Increased Levels

Decreased Levels

Acute rheumatic fever

Advanced systemic lupus erythematosus
(SLE)

Rheumatoid arthritis

Glomerulonephritis

Early SLE

Renal transplant rejection

Most cancers

Chronic active hepatitis
Cirrhosis
Multiple sclerosis
Anemias
Gram-negative septicemia
Subacute bacterial endocarditis
Inborn C3 deficiency
Serum sickness
Immune complex disease

Rheumatoid spondylitis

SLE

Juvenile rheumatoid arthritis

Lupus nephritis

Most cancers

Acute poststreptococcal glomerulonephritis
Chronic active hepatitis
Cirrhosis
Subacute bacterial endocarditis
Inborn C4 deficiency
Serum sickness
Immune complex disease

Reference Values
Conventional Units
Total complement (CH50)
C3
C4

40–90 U/mL

SI Units
0.4–0.9 g/L

Men

80–180 mg/dL

0.80–1.80 g/L

Women

76–120 mg/dL

0.76–1.20 g/L

Men

15–60 mg/dL

0.15–0.60 g/L

Women

15–52 mg/dL

0.15–0.52 g/L

Note: Values for total complement, C3, and C4 may vary according to laboratory methods
and the reference range established by the laboratory performing the test.

CHAPTER 3—Immunology

inflammatory disorders as indicated by altered C3
and C4 levels (see Table 3–5)
Monitoring of progress after various immune and
inflammatory disorders as indicated by levels
approaching or within the reference ranges
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Complications and precautions: Note and report
types and deficiencies of complement components and their relation to an inflammatory or
infectious disorder.

and Immunologic Testing

Reference Values
Immune complexes are not normally found in
the serum.

INTERFERING FACTORS

Rough handling of the sample and failure to
transport the sample promptly to the laboratory
may cause deterioration of any immune
complexes present.
INDICATIONS FOR IMMUNE COMPLEX ASSAYS

Suspected immune disorders such as SLE, scleroderma, dermatomyositis, polymyositis, glomerulonephritis, and rheumatic fever as indicated by
the presence of immune complexes
Monitoring of the effects of therapy for various
immune disorders
Suspected serum sickness or allergic reactions to
drugs as indicated by the presence of immune
complexes
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).

IMMUNE COMPLEX ASSAYS
Immune complexes are combinations of antigen and
antibody that are capable of activating the complement cascade. Although the activated agent is
directed against the immune complex, tissues that
are “innocent bystanders” may also be severely
damaged, especially when immune complexes are
produced too rapidly for adequate clearance by the
body. Immune complexes are commonly present in
autoimmune disorders and also are found in
immune hypersensitivities that do not involve
autoimmunity.
Two methods can be used to determine the circulating immune complexes (CIC) in the blood in the
diagnosis of autoimmune and infectious diseases.
One involves screening for large amounts of precipitate in serum that has been refrigerated. The other
is the Raji cell assay, in which these specially
prepared cells that bind complement (C3) are
combined with the serum sample and then incubated. Further incubation with a radiolabeled
antihuman immunoglobulin allows for binding of
the CIC on the surface of the Raji cells. This is
followed by washing of the cells and measurement of
the radioactivity to determine the CIC in the
blood.25

THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Complications and precautions: Note and report
the presence of complexes in relation to signs and
symptoms of an existing or suspected autoimmune disease.

RADIOALLERGOSORBENT TEST
FOR IgE
IgE antibodies are responsible for hypersensitivity
reactions described as atopic (allergic) or anaphylactic. Examples of IgE-mediated diseases include hay
fever, asthma, certain types of eczema, and idiosyncratic, potentially fatal reactions to insect venoms,
penicillin, and other drugs or chemicals.

SECTION I—Laboratory

Tests

Almost all of the body’s active IgE is bound to
tissue cells, with only small amounts in the blood.
Thus, IgE antibodies cannot circulate in search of
antigen but must wait for antigens to appear in their
area. Once this happens, the interaction of IgE antibodies with specific antigens causes mast cells (tissue
basophils) to release histamine and other substances
that promote vascular permeability.26
The radioallergosorbent test (RAST) for IgE
measures the quantity of IgE antibodies in the serum
after exposure to specific antigens selected on the
basis of the person’s history. RAST has replaced skin
tests and provocation procedures, which were inconvenient, painful, and hazardous to the client.
Reference Values
If the client is not allergic to the antigen, IgE
antibody is not detected. A positive test result in
relation to a specific antigen is more than 400
percent of control. Results of the test may vary
depending on the reference serum used for the
control.

INTERFERING FACTORS

Radioisotope tests within 1 week before the test
may alter results.
INDICATIONS FOR RADIOALLERGOSORBENT
TEST FOR IgE

Onset of asthma, hay fever, dermatitis
Systemic reaction to insect venom, drugs, or
chemicals
Identification of the specific antigen(s) to which
the client reacts
Monitoring of response to desensitization procedures
NURSING CARE BEFORE THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube or other type of blood
collection tube, depending on laboratory preference.
The allergy panel desired should be indicated on the
laboratory request form. Each panel usually consists
of six antigens.

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Complications and precautions: Instruct client
to avoid contact with substances, ingestion of
drugs, or exposure to insects that cause reactions.

AUTOANTIBODY TESTS
Antibodies directed against “self ” components are
believed to be responsible for the pathogenesis of
many diseases. Some show widespread systemic
involvement (Table 3–6), whereas others are
confined to a specific organ system (Table 3–7).
INTERFERING FACTORS

Many drugs may cause false-positive results in
certain autoantibody tests (Table 3–8).
INDICATIONS FOR AUTOANTIBODY TESTS

Signs and symptoms of the disorder for which
each test is pathognomonic or for which the test
provides confirming data (see Tables 3–6 and 3–7)
Monitoring of response to treatment for autoimmune disorders
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Food and fluids are not restricted, except for the
cryoglobulin test, which requires a 4-hour fast
from food.
THE PROCEDURE

The procedure is the same for all autoantibody tests,
except cryoglobulins. A venipuncture is performed
and the sample collected in a red-topped tube. For
cryoglobulins, the sample is collected in a
prewarmed red-topped tube. The sample must be
handled gently to avoid hemolysis and sent
promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample. Resume food withheld
before the test.
Complications and precautions: Note and report
the presence of cell-specific or tissue-specific antibodies in relation to a suspected disease and the
presenting signs and symptoms.

CHAPTER 3—Immunology

TABLE 3–6

•

and Immunologic Testing

Summary of Autoantibody-Related Disorders and Tests
Used in Diagnosis
Incidence

Antibody
C-reactive
protein (CRP)

Present in 90% or
More of Cases

Present in
50–90% of Cases

Present in 50%
of Cases

Rheumatic fever

Active tuberculosis

Multiple sclerosis

Rheumatoid arthritis

Gout

Guillain-Barré syndrome

Acute bacterial infections

Advanced cancers

Scarlet fever

Viral hepatitis

Leprosy

Varicella

Cirrhosis

Surgery

Burns

Intrauterine contraceptive
devices

Peritonitis
Rheumatoid
factor (RF)

Antinuclear antibodies (ANA)

Rheumatoid arthritis

Systemic lupus erythematosus (SLE)

Early rheumatoid arthritis

Advanced age

SLE

Juvenile rheumatoid
arthritis (20%)

Scleroderma

Infectious diseases

Dermatomyositis

Healthy adults (5%)

Sjögren’s syndrome

Burns

Scleroderma

Asbestosis

Drug-induced SLE-like
syndrome

Juvenile chronic
polyarthritis

Chronic active hepatitis

Rheumatoid arthritis

Heart disease, with longterm procainamide therapy

Rheumatic fever

Myasthenia gravis
Advanced age
Dermatomyositis
Polyarteritis nodosa
Primary biliary cirrhosis
Anti-DNA

Active SLE

SLE in remission

Juvenile rheumatoid
arthritis
Progressive systemic sclerosis
Drug-induced SLE-like
syndrome
Uveitis

Cold agglutinins

Atypical pneumonia

Viral infections

Congenital syphilis

Influenza

Infectious mononucleosis

Malaria

Pulmonary embolus

Lymphoreticular malignancy

Anemia
Cirrhosis
(Continued on following page)

SECTION I—Laboratory

TABLE 3–6

•

Tests

Summary of Autoantibody-Related Disorders and Tests
Used in Diagnosis (Continued)
Incidence
Present in 90% or
More of Cases

Antibody

Present in 50%
of Cases

Present in
50–90% of Cases

Lupus erythematosus (LE)
cell preparation

SLE

—

Cryoglobulins

Raynaud’s syndrome

—

Cryoglobulinemia

Reference Values
Conventional Units
C-reactive protein (CRP)
Antinuclear antibodies (ANA)
Rheumatoid factor (RF)
Anti-DNA antibodies

Negative to trace
Negative
Negative (1:20)
1 mg/mL

Antimitochondrial antibodies

Negative

Antiskin antibodies

Negative

Antiadrenal cortex antibodies

Negative

Antithyroglobulin, antithyroid microsome antibodies

1:100

Antismooth muscle antibodies

Negative

Antiparietal cell, anti-intrinsic factor antibodies

Negative

Antistriated muscle antibodies

Negative

Antimyocardial antibodies

Negative

Antiglomerular basement membrane antibodies

Negative

Anti-insulin antibodies

Negative

Acetylcholine receptor antibodies

Negative

Anti-SS-A and anti-SS-B antibodies

Negative

Lupus erythematosus cell test (LE prep)

Negative

Cold agglutinins
Cryoglobulins

1:16
Negative

Antiglobulin tests (Coombs’ tests)*
Direct

Negative

Indirect

Negative

* See also Chapter 4.

SI Units

2.0 kU/L

CHAPTER 3—Immunology

TABLE 3–7
Antibody Target
Cell/Tissue

•

and Immunologic Testing

Cell- and Tissue-Specific Antibodies
Diseases for Which the Test
Is Usually Diagnostic

Other Diseases in Which This
Antibody May Also Be Present

Skeletal muscle

Myasthenia gravis

Cardiac muscle

Myocardial infarction

Acute rheumatic fever

Smooth muscle

Chronic active hepatitis

Biliary cirrhosis
Viral hepatitis
Infectious mononucleosis
Systemic lupus erythematosus
(SLE) (10%)

Mitochondria

Primary biliary cirrhosis

Chronic active hepatitis

Drug-induced jaundice

Viral hepatitis
SLE (20%)

Skin

Pemphigus

—

Altered IgG

Rheumatoid arthritis

—

Adrenal cells

Addison’s disease

—

Intrinsic factor, parietal cells

Pernicious anemia

SLE (5%)

Long-acting thyroid stimulator

Graves’ disease

—

Hashimoto’s thyroiditis
Long-acting thyroid microsomes

Primary myxedema

SLE (5%)

Juvenile lymphocytic thyroiditis

Pernicious anemia (25%)

Graves’ disease

Allergies

Healthy adults
Hashimoto’s thyroiditis

Pernicious anemia

Primary myxedema

Allergies

Graves’ disease

Healthy adults (5–10%)

Salivary ducts

Sjögren’s syndrome

Rheumatoid arthritis

Red blood cell membrane

Autoimmune hemolytic anemia

Transfusion reaction

Platelet cell membrane

Idiopathic thrombocytopenic
purpura

—

Basement membranes of
lungs, renal glomeruli

Goodpasture’s syndrome

—

Thyroglobulin

Glomerulonephritis

IMMUNOLOGIC ANTIBODY TESTS
Exposure to bacteria, fungi, viruses, and parasites
induces production of antibodies that either can be
identified only during acute disease or can remain
identifiable for many years. Exposure can be through
immunization, from previous infection so minimal

that it passed unrecognized, or from current symptomatic or prepathogenic infection. Detection and
identification of specific antibodies in the blood by
assays performed in the serology laboratory are
preferred for obtaining diagnostic information. This
is especially true when the antigen assays or culture
techniques performed in the microbiology labora-

SECTION I—Laboratory

Tests

•

Drugs that May Cause
False-Positive Reactions in
Autoantibody Tests*

TABLE 3–8

Antibiotics

Para-aminosalicylic acid

Anti-DNA

Penicillin

Chlorpromazine

Phenylbutazone

Clofibrate

Phenytoin

Ethosuximide

Procainamide

Griseofulvin

Propylthiouracil

Hydralazine

Quinidine

Isoniazid

Radioactive diagnostics

Mephenytoin

Streptomycin

Methyldopa

Sulfonamides

Methysergide

Tetracyclines

Oral contraceptives

Trimethadione

* The drugs listed here may cause false-positive reactions in the following tests: antinuclear antibodies,
lupus erythematosus cell test, and antiglobulin
(Coombs’) tests.

Various methods for detection of antibodies are
used. They include immunoprecipitation, complement fixation, neutralization assay, particle
agglutination/agglutination inhibition, immunofluorescence assay, enzyme immunoassay, and radioimmunoassay. The concentrations of antibody are
referred to as the titer, and their predictable patterns
are useful in both diagnosing a disease and monitoring its course.

Fungal Infection Antibody Tests
Most pathogenic fungi elicit antibodies in immunocompetent hosts. Assays for fungal antibodies are
used to diagnose invasive deep-seated recent or
current infections. Serologic testing for parasitic
organisms or antibodies in the blood sample is also
used in the diagnosis of infections. Depending on
the antibody to be identified, testing uses the various
assay techniques mentioned in the introduction of
this chapter. Table 3–9 indicates the fungal and parasitic infections for which tests are available and the
causes of alteration in the test results.
INTERFERING FACTORS

tory are ineffective in producing a causative agent or
in clients who cannot tolerate the invasive procedure
necessary to collect a specimen for culture.

TABLE 3–9
Organism

•

Recent fungal skin tests may alter results.
Obtaining the sample near fungal skin lesions
may contaminate the specimen and alter test
results.

Fungal and Parasitic Immunologic Tests
Tests Available

Causes of Alterations

Fungi
Histoplasma capsulatum

CF, I, LA

Prior exposure to organism or cross-reactive
agent, recent skin test

Blastomyces dermatitidis

EIA

Blastomycosis

Coccidioides immitis

CF, I, LA

Acute or chronic infection, repeated skin testing
with coccidioidin

Aspergillus fumigatus

CF, I

Pulmonary aspergillosis, aspergillosis allergy

Cryptococcus neoformans

Test demonstrates antigen, not antibodies, in
infection

Sporotrichum schenckii

Deep tissue infection

Candida albicans

Systemic infection, vaginal infection

Toxoplasma gondii

IFA, EIA

Acute or chronic toxoplasmosis

Entamoeba histolytica

A, IFA

Amebic dysentery

Parasites

Aagglutination, CFcomplement fixation, Iimmunodiffusion, IFAindirect fluorescent antibody tests, LAlatex
agglutination, EIAenzyme immunoassay.

CHAPTER 3—Immunology

and Immunologic Testing

Reference Values
Organism

Complement Immunodiffusion
Fixation Titers
Test
Agglutination

Other
Tests

Fungi
Histoplasma
capsulatum

1:8

Negative

—

Blastomyces
dermatitidis

1:8

Negative

—

Coccidioides
immitis

1:2

Negative

—

Aspergillus
fumigatus

1:8

Negative

—

Cryptococcus
neoformans

—

Negative

—

Sporotrichum
schenckii

—

1:40

—

Candida albicans

—

Latex agglutination
(LA) test 1:8

Toxoplasma gondii

—

Indirect fluorescent
antibody tests 1:16

Entamoeba histolytica

—

Indirect hemagglutination
test 1:32

Parasites

INDICATIONS FOR FUNGAL INFECTION
ANTIBODY TESTS

Suspected infection with the fungus for which the
test is performed
Persistent pulmonary symptoms after pneumonia
Acute meningitis of unknown etiology
Identification of the state of infection by rising or
falling titers
Confirmation of previous exposure to the fungus
despite absence of clinical signs of illness
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
The client should be interviewed to determine if
he or she has undergone any recent fungal skin
tests that may alter test results.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. Venipuncture should

not be performed on or near any fungal skin lesions.
The sample must be handled gently and transported
promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Complications and precautions: Note and report
signs and symptoms of fungal infection, superficial or deep-seated presence, and rise of serum
antibodies to a specific fungal or parasitic
microorganism or culture identification of the
microorganism. Assess factors that can cause
infection such as travel or residence in areas where
infection is endemic; antibiotic or corticosteroid
therapy; chemotherapy; presence of an intravenous (IV) line to administer fluids, medications, or parenteral nutrition; or invasive
procedures such as surgery. Note symptoms of
vaginitis such as itching and foul-smelling,
white, cheeselike secretion. Administer ordered
antifungals via oral, IV, or vaginal routes. Monitor

SECTION I—Laboratory

TABLE 3–10

•

Tests

Commonly Performed Serologic Tests for Diagnosis
of Recent Bacterial Infections

Organism

Clinically
Significant Result*

Test

Staphylococcus aureus

Immunodiffusion for teichoic acid antibodies

1:4

Streptococcus pyogenes

Antistreptolysin O (ASO)

1:240

Anti-DNAase B

1:240

Antihyaluronidase

4x titer rise

Salmonella typhi (typhoid fever)

Widal test

4x titer rise

Legionella pneumophila
(Legionnaires’ disease)

Indirect immunofluorescence

1:256

Treponema pallidum

Rapid plasma reagin (RPR)

1:8

Venereal Disease Research Laboratory
(VDRL)

1:8

Fluorescent treponemal antibodyabsorption (FTA-ABS) (IgM)

Positive

Borrelia burgdorferi (Lyme
disease)

Indirect immunofluorescence

1:128

Mycoplasma pneumoniae (atypical pneumonia)

Cold agglutinins
Complement fixation

1:128
1:32

Rickettsia rickettsii (spotted and
typhus fevers)

Weil-Felix (OX-19)

1:320

* Titers greater than or equal to those displayed in the table or fourfold or greater rises in titer between acute and
convalescent sera are only suggestive of recent infection by all of the agents listed. Titers less than those
displayed in the table do not rule out infection.
Adapted from Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 11. FA
Davis, Philadelphia 2000, p 709.

respiratory status for changes in rate, ease, depth,
and breath sounds and place on respiratory
precautions according to universal standards, if
appropriate. Prepare client for skin tests if
ordered.

bacterial antibody detection of recent or existing
infectious diseases are individually outlined and
discussed. They include staphylococcal, streptococcal, and febrile/cold agglutinin tests.

STAPHYLOCOCCAL TESTS
Bacterial Infection Antibody Tests
Although most bacterial infections are successfully
diagnosed by culture, serologic testing is performed
for antibodies to screen for past, recent, or existing
infection in those with negative cultures. Clients in
whom these tests are performed usually have
sustained a fever of unknown origin or have been
treated with antimicrobials. Table 3–10 indicates the
commonly performed tests for recent bacterial
infections for identification and titers that are
suggestive of recent infection. Also, specific individual serologic tests that have special applications in

The teichoic acid antibody is measured to diagnose
infections caused by Staphylococcus aureus. Teichoic
acid attaches to the organism’s cell wall. High titers
are associated with invasive infections such as bacterial endocarditis and osteomyelitis.
Reference Values
Teichoic acid antibody titer <1:2
INTERFERING FACTORS

Improper technique in testing

CHAPTER 3—Immunology

INDICATIONS FOR STAPHYLOCOCCAL TESTS

Suspected infection caused by S. aureus
Diagnosis of osteomyelitis or endocarditis caused
by a bacterial infection
Monitoring of ongoing therapy administered for
gram-positive bacterial infections
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Inform the client that repeat or serial blood
sampling and testing can be performed.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The tube should be
labeled as an acute or convalescent sample,
whichever applies.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Inform the client of the time to return for a repeat
test, usually in 2 weeks, to determine the change in
titers between the acute and convalescent stages.
Abnormal values: Note and report increases in
titers. Assess for signs and symptoms associated
with staphylococcal infections such as temperature elevation, bone pain in osteomyelitis, and
changes in heart sounds in endocarditis.
Administer ordered analgesic and antibiotic therapy and instruct in preventive antibiotic therapy
in those at risk.

STREPTOCOCCAL TESTS
Group A -hemolytic streptococci produce a variety
of extracellular products capable of stimulating antibody production. Such antibodies do not act on the
bacteria and have no protective effect, but their existence indicates recent active streptococci. Antibody
production is most reliably noted in response to
streptolysin O, and the test for this antibody is
termed an antistreptolysin O (ASO) titer. Antibodies
in response to hyaluronidase (AH), streptokinase
(anti-SK), deoxyribonuclease B (ADN-B), and
nicotinamide (anti-NADase) also can be produced.
When ASO titers are low, tests for these latter antibodies can be produced to substantiate the diagnosis, because they are more sensitive tests.
Elevated antistreptococcal antibody titers can
occur in healthy carriers of -hemolytic strepto-

and Immunologic Testing

cocci. Elevated levels also are seen in those with
rheumatic fever, glomerulonephritis, bacterial endocarditis, scarlet fever, otitis media, and streptococcal
pharyngitis.
Reference Values
ASO titer
Preschool children

85 Todd units/mL

School-age children

170 Todd units/mL

Adults

85 Todd units/mL

ADN-B titer
Preschool children

60 Todd units/mL

School-age children

170 Todd units/mL

Adults

85 Todd units/mL

AH titer

128 Todd units/mL

Anti-SK titer

128 Todd units/mL

INTERFERING FACTORS

Therapy with antibiotics and adrenal corticosteroids may result in falsely decreased levels.
Elevated blood -lipoproteins may result in
falsely elevated levels.
INDICATIONS FOR STREPTOCOCCAL TESTS

Suspected streptococcal infection, to confirm the
diagnosis
Detection and monitoring of response to therapy
for poststreptococcal illnesses such as rheumatic
fever and glomerulonephritis
Differentiation of rheumatic fever from rheumatoid arthritis, with the former indicated by
elevated levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Medications that the client is currently taking or
has recently taken should be noted, because therapy with antibiotics and adrenal corticosteroids
may alter test results.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. A capillary sample
may be obtained in infants and children as well as in
adults for whom a venipuncture may not be feasible.
The sample must be handled gently and sent
promptly to the laboratory.

SECTION I—Laboratory

Tests

Reference Values
Weil-Felix reaction (Proteus antigen test)

1:80

Widal’s test (O and H antigen tests)

1:160

Brucella agglutination test (slide agglutination test)

1:80

Tularemia agglutination test (tube dilution test)

1:40

M. pneumoniae (cold agglutinin test)

1:32

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Abnormal values: Note and report increased
levels of specific tests in relation to signs and symptoms of joint or renal disease. Assess for joint pain,
elevated temperature, sore throat, and history of a
recent infection. Administer ordered antipyretics,
analgesics, and antibiotic therapy. Prepare for additional tests if more specificity is needed.

FEBRILE/COLD AGGLUTININ TESTS
Febrile agglutinin tests are performed concurrently
with blood culture for microorganism identification
to diagnose the infectious cause of a febrile condition. The test is performed with the use of antigens
to specific organisms and their reaction (agglutination) with antibodies in the client’s blood serum.
Diseases that can be diagnosed using these tests,
along with the type of febrile agglutinin test used,
are listed in Table 3–11.
The cold agglutinin test is performed to identify

TABLE 3–11

•

cold agglutinins, antibodies that result from
Mycoplasma pneumoniae infection. This infection is
caused by a nonbacterial agent, but it still manifests
a febrile condition. The antibodies cause agglutination of red blood cells at temperature ranges of 35.6
to 46.4F (2 to 8C), with a positive titer resulting in
those with atypical pneumonia or cold agglutination
disorders, depending on the severity of the disease.
INTERFERING FACTORS

Vaccination, chronic exposure to infected
animals, and cross-reactions with other antibodies may result in falsely elevated titers.
Individuals who are immunosuppressed or are
receiving antibiotic therapy may have false-negative results.
INDICATIONS FOR FEBRILE/COLD
AGGLUTININ TESTS

Determination of possible cause of fever of
unknown origin (FUO)
Suspected typhus, Rocky Mountain spotted fever,
or other disorder for which selected tests are
specific

Febrile Agglutinin Tests

Diseases

Test

Rickettsial Infections
Rocky Mountain spotted fever, typhus (murine, scrub,
epidemic, and recrudescent)

Weil-Felix reaction (Proteus antigen test)

Salmonella Infections
Typhoid and paratyphoid fevers

Widal’s test (O and H antigen tests)

Brucella Infections
Cattle, hog, goat (Hosts may transmit infections to
humans.)

Brucella agglutination test (slide agglutination
test)

Tularemia
Rabbit fever and deer fly fever

Tularemia agglutination test (tube dilution test)

CHAPTER 3—Immunology

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample must be
handled gently to avoid hemolysis and transported
immediately to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Abnormal values: Note and report increased titers
in cold agglutinin test in relation to specific signs
and symptoms of the disease such as fever, change
in respiratory status, and nonproductive cough;
also note increased titers in febrile disorders in
relation to specific infectious processes. Assess for
culture results or need to obtain culture for organism identification; place on enteric precautions as
appropriate. Administer ordered antimicrobial
therapy. Inform client of the need for serial testing
during acute and convalescent stages.

•

Infection with Treponema pallidum provides two
distinct categories of antibodies: (1) reagin (a
nonspecific antibacterial antibody) and (2) antitreponemal antibody. Reagin tests, by their nature
nonspecific, include the Wassermann and Reiter
complement fixation tests, now seldom used. Reagin
tests currently used for screening are the Venereal
Disease Research Laboratory (VDRL) and rapid
plasma reagin (RPR) flocculation tests. Because
reagin screening tests often yield false-positive reactions (Table 3–12), positive test results are confirmed
by means of treponemal antibody tests. The best of
these is the fluorescent treponemal antibodyabsorption test with absorbed serum.27

FLUORESCENT TREPONEMAL
ANTIBODY-ABSORPTION TEST
The fluorescent treponemal antibody-absorption
(FTA-ABS) test is conducted on a sample of the
client’s serum that is layered onto a slide fixed with
T. pallidum organisms. If the antibody is present, it
will attach to the organisms and can subsequently be
demonstrated by its reaction with fluoresceinlabeled antiglobulin serum.
The FTA-ABS test rarely gives false-positive
results, except sporadically in clients with SLE; the

Causes of False-Positive Reactions to Reagin Tests

Transiently Positive

Persistently Positive
OCCURRING IN

10%

OF CLIENTS WITH THE FOLLOWING:

Infectious mononucleosis

Systemic lupus erythematosus

Malaria

Rheumatoid arthritis

Brucellosis

Illicit drug use

Typhus

Hepatitis

Lymphogranuloma venereum

Leprosy

Subacute bacterial endocarditis

Malaria
Advanced age
Nonsyphilitic treponemal disease (pints, yaws, bejel)

OCCURRING RARELY IN CLIENTS WITH THE FOLLOWING:

Hepatitis

Tuberculosis

Measles

Scleroderma

Chickenpox
Mycoplasma pneumonia
After smallpox vaccination

Syphilis Tests

Suspected “carrier” state for typhoid
Positive blood or stool culture for Salmonella

TABLE 3–12

and Immunologic Testing

SECTION I—Laboratory

Tests

pattern of fluorescence may have an atypical beaded
appearance in these cases. Elderly individuals and
clients with immune complex diseases occasionally
also have false-positive results.28

Note that these tests are not specific for antibodies to T. pallidum, and many factors, including laboratory procedures, may cause false-positive results
(see Table 3–12).

Reference Values

Negative

INTERFERING FACTORS

False-positive results may occasionally occur in
elderly individuals and in clients with SLE or
other immune complex diseases.
INDICATIONS FOR FLUORESCENT TREPONEMAL
ANTIBODY-ABSORPTION TEST

Confirmation of the presence of treponemal antibodies in the serum (Note: The test also may be
applied to cerebrospinal fluid [CSF] to diagnose
tertiary syphilis.)
Verification of syphilis as the cause of positive
VDRL and RPR test results
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
The client’s history should be reviewed for possible sources of false-positive results.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample must be
handled gently to avoid hemolysis and must be
transported promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

VENEREAL DISEASE RESEARCH
LABORATORY AND RAPID PLASMA
REAGIN TESTS
The VDRL and RPR tests are flocculation tests
for reagin and are used in screening for syphilis.
The VDRL test uses heat-inactivated serum and
can be made on slides or in tubes. The RPR test
uses unheated serum or plasma, which is added
to a reagent-treated plasma card. Automated procedures have been adapted for multichannel analyzers.29

Results are reported qualitatively as strongly
reactive, reactive, weakly reactive, or negative. A
degree of quantification is possible by diluting
the serum and reporting the highest titer that
remains positive. Positive results must be further
evaluated either by repeat testing or with tests
specific for antitreponemal antibodies.30

INTERFERING FACTORS

Many factors, including laboratory procedures,
may cause false-positive results (see Table 3–12).
INDICATIONS FOR VENEREAL DISEASE
RESEARCH LABORATORY AND RAPID
PLASMA REAGIN TESTS

Routine screening for possible syphilis
Known or suspected exposure to syphilis, including congenital syphilis
Verification of an antigen-antibody reaction to
reagin, although a positive result is not necessarily
diagnostic for syphilis
Monitoring of response to treatment for syphilis,
with effective treatment indicated by decreasing
titers
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
A thorough history should be obtained to identify
possible causes of false-positive results (see Table
3–12).
It is recommended that alcohol ingestion be
avoided for 24 hours before the test.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample must be
handled gently to avoid hemolysis and transported
promptly to the laboratory.
For neonates, a sample of cord blood may be
obtained at delivery. Subsequent samples of
venous blood from the infant may be required if
the mother’s titer is lower than that of the infant,
indicating active syphilis in the infant despite
successful treatment of the mother.

CHAPTER 3—Immunology

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Abnormal values: Note and report a positive
result and degree of reactivity. Assess for pregnancy and sexual contacts. Ensure that positive
results are reported to the health department for
follow-up and treatment of sexual contacts.
Administer ordered antibiotic medication regimen. Instruct in importance of preventive measures to take during sexual activity, especially if
pregnant, and the screening and treatment of
sexual partner. Inform that the test should be
repeated every 3 months for at least 1 year or until
the reaction becomes negative. Provide a sensitive,
nonjudgmental environment for the client.

Viral Infection Antibody Tests
Viral cultures either are not available or can be
disproportionately expensive in relation to the
potential benefit, because effective antiviral treatment is not available for most organisms. For these
reasons, viral antibody tests are used to determine
exposure to and existing infections with certain
viruses that are difficult to culture, or they are used
to screen donors before blood donation or organ
transplantation (Table 3–13).
Because many types of tests can be performed,
requests for viral antibody tests must be specific and
include enough clinical information to permit selection of the appropriate study. A request for “viral
studies” is meaningless. Antibody assays for detection of some specific disease entities, although
included in Table 3–13, are outlined and discussed in
the next section. They include infectious mononucleosis, hepatitis, and AIDS tests.
Reference Values
In general, lack of exposure to the virus yields a
negative test result. Reference values vary with
the type of viral antibody test. The laboratory
performing the test should be consulted.

INDICATIONS FOR VIRAL INFECTION ANTIBODY
TESTS

Suspected AIDS or exposure to human immunodeficiency virus (HIV)
Retrospective confirmation of viral infection
Determination of immunity to rubella in women
of childbearing age

and Immunologic Testing

Confirmation of exposure to rubella in early pregnancy
Suspected herpes encephalitis
Determination of immunity to chickenpox in
children with leukemia, because this infection
may be fatal in such children
Identification of asymptomatic carriers of
cytomegalovirus (CMV)
Monitoring of the course of prolonged viral
disease
Monitoring of mothers and neonates for exposure
to viral infections that may cause congenital
disease in the newborn infant (usually done by the
toxoplasmosis, other infections, rubella, CMV
infection, and herpes simplex [TORCH] test; see
Table 3–13)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample must be
handled gently to avoid hemolysis and transported
promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Women of childbearing age with low rubella titers
should be appropriately immunized.
Abnormal test results, complications, and
precautions: Response is dependent on the type
of viral antibody test and the specific infectious
process identified in Table 3–13. See the specific
tests that follow for nursing implications related
to aftercare and observations.

INFECTIOUS MONONUCLEOSIS TESTS
Diagnosis of infectious mononucleosis, caused by
Epstein-Barr virus (EBV), depends on serologic
(antigen-antibody) confirmation of clinical manifestations of the disease that include fever, sore
throat, and lymphadenopathy. EBV stimulates the
formation of new antigens that, in turn, stimulate a
humoral and cellular immune response. The
humoral response is characterized by an increased
titer of the antibodies IgG and IgM early in the
disease. The cellular response is characterized by the
activation of T cells later in the illness in response to
the EBV-induced infection.

SECTION I—Laboratory

Tests

TABLE 3–13

•

Tests for Viral Diseases

Virus/Disease

Serologic Tests

Respiratory syndromes
Influenza

CF, HI

Parainfluenza
Adenoviruses

CF, HI, NT

Chlamydia

CF, IFA

Respiratory syncytial virus
Arbovirus

CF, HI, NT

Colorado tick fever
Yellow fever
Meningoencephalitis

Antibodies to echo, herpes, polio, and coxsackie viruses by
neutralization tests

Herpes viruses

Fluorescein-tagged antibodies in cells, EIA, indirect HI

Herpes simplex*
Varicella zoster
Cytomegalovirus*
Epstein-Barr virus

Heterophile antibody (Monotest), agglutination test, IFA

Rubella*

IgM titers, CF, HI

Mumps
Measles
Infectious hepatitis

IgM titers, IgG titers, hepatitis A virus antibodies (anti-Ha),
CF, RIA

Serum hepatitis

Antibodies to hepatitis B virus surface antigen (HBsAb)
(HBsAg)

Cytomegalic inclusion disease

CF, HI, EIA

Acquired immunodeficiency syndrome
(AIDS)

Human immunodeficiency virus (HIV-1) antibodies, IFA,
EIA, WIB

Leukemia and tropical spastic paraparesis

HTLV-1 and HTLV-II antibodies, ETA, WIB

* In the TORCH test, antibodies to Toxoplasma gondii (see Table 3–9), rubella virus, cytomegalovirus, and
herpesvirus are measured.
CFcomplement fixation, EIAenzyme immunoassay, HIhemagglutination inhibition, IFAimmunofluorescent
antibody, NTneutralization test, RIAradioimmunoassay, WIBWestern immunoblot assay.

The hallmark of EBV infection is the heterophil
antibody, also called the Paul-Bunnell antibody, the
formation of which is stimulated by the virus. The
heterophil antibody is an IgM that agglutinates
sheep or horse red cells. Forssman antibody, which
can be present in the serum of normal people as
well as in that of individuals with serum sickness,
also agglutinates with sheep erythrocytes. The
Davidsohn differential absorption test can be used
to distinguish between the Paul-Bunnell antibody
and the Forssman antibody. Currently, more rapid

and sensitive tests are available that use red blood
cells from horses in a single-step agglutination test.31
These tests (e.g., Monospot, Monoscreen) are used
as screening tests for infectious mononucleosis and
are gradually replacing the more traditional techniques.
Reference Values
Negative, or a titer of less than 1:56 heterophile
antibodies

CHAPTER 3—Immunology

INTERFERING FACTORS

False-positive results may occur in the presence of
narcotic addiction, serum sickness, lymphomas,
hepatitis, leukemia, cancer of the pancreas, and
phenytoin therapy.
INDICATION FOR INFECTIOUS MONONUCLEOSIS
TESTS

Suspected infectious mononucleosis (Of individuals with EBV infectious mononucleosis, 95
percent will have a positive result, 86 percent in
the first week of illness.)
NURSING CARE BEFORE THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. For screening tests,
the directions accompanying the test kit are
followed. For traditional tests, the sample should be
sent to the laboratory promptly.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Abnormal values: Note and report increased
heterophile titer or titers against EBV. Assess signs
and symptoms of infection such as fever, chills,
malaise, sore throat, anorexia, enlarged lymph
nodes, and fatigue. Provide rest, adequate nutritional and fluid intake, and activities that do not
cause fatigue or stress.

HEPATITIS TESTS
Hepatitis tests include measurements of serologic
markers that appear during the course of the disease
caused by the hepatitis A virus (HAV), hepatitis B
virus (HBV), hepatitis C virus (HCV), hepatitis D
virus (HDV), and hepatitis E virus. Laboratory
methods used in the detection of specific antigens or
antibodies include radioimmunoassay (RIA) and
enzyme immunoassay (EIA).
Hepatitis A is a self-limiting disease that does not
usually cause liver damage or a chronic infectious
state. It occurs as the result of oral ingestion of the
virus and is characterized by malaise, anorexia, fever,
and nausea. The virus is present in the feces, but

and Immunologic Testing

diagnosis is based on serologic markers (anti-HAV,
IgM, IgG) identified in the laboratory. The diagnosis
is made for hepatitis A if anti-HAV antibodies can
be demonstrated in the early acute stage of the
disease or if there is a high level of IgM anti-HAV
compared to the level of the IgG antibody to HAV.
IgM antibodies appear in the early stages, and IgG
antibodies indicate past infection and immunity to
reinfection.
Hepatitis B, also known as the Australian antigen,
is a more serious, prolonged disease that can result
in liver damage and chronic active hepatitis. HBV
can be found in the blood, feces, saliva, semen, sweat,
urine, or any body fluid of infected individuals and
can be transmitted by exposure to blood products or
parenteral contact with articles contaminated with
material containing the virus. Diagnosis is made by
identification of the hepatitis B surface antigen
(HBsAg) circulating in the blood before and during
the acute early stage before enzyme elevations or in
chronic carriers after an acute illness. It is the first
indicator of acute hepatitis infection. The recovery
from and immunity to HBV as late as 6 to 10 months
after an active infection are identified by the detection of anti-HBs. The presence of hepatitis B antibody (anti-HBe, HBeAb) indicates the resolution of
acute infection or, along with positive HBsAg, indicates an asymptomatic, healthy carrier. The presence
of hepatitis B e antigen (HBeAg) is an early indicator of hepatitis B infection. If HBeAg persists for
more than 3 months, it is indicative of chronic infection. Delta hepatitis coinfects with HBV, and diagnosis is made by detection of the antibodies (anti-D)
in the blood.
Hepatitis C is a parenterally acquired disease
usually caused by blood transfusion but also by IV
drug abuse. The disease can lead to chronic hepatitis
and cirrhosis of the liver. The test is performed to
detect the antibodies to HCV in the blood of those
at risk for the infection and transmission of the virus
as a blood donor. Antibody formation can take as
long as a year after exposure to the virus.
Hepatitis D is caused by a “defective” virus that
can produce infection only when HBV is present.
HDV antigens do not circulate and are found only in
hepatocytes. Hepatitis D occurs with HBV and can
result in more serious disease in individuals with
chronic HBV infection. Hepatitis D is also known as
delta agent hepatitis.
Hepatitis E is similar in presentation and disease
course to hepatitis A. It occurs primarily in Asia,
Africa, and South America.32
INTERFERING FACTORS

The administration of radionuclides within 1

SECTION I—Laboratory

Tests

body fluids, personal contact through sexual
activity, or presence of pregnancy (the infection
could be transmitted to the infant).33

Reference Values
Hepatitis A
Anti-HAV

Negative

THE PROCEDURE

IgM

Negative

IgG

Negative

A venipuncture is performed and the sample
collected in a red-topped tube. For screening tests,
the directions accompanying the test kit are
followed. For traditional testing, the sample should
be sent to the laboratory promptly, with the test
performed within 7 days or frozen for future analysis.

Hepatitis B
Surface antigen (HBsAg)

Negative

Surface antibody (HBsAb)

Negative

B antigen (HBeAg)

Negative

B antibody (HBeAb)

Negative

Core antibody (anti-HBcAb)

Negative

Hepatitis C
C antibody (anti-HCV)

Negative

Hepatitis D
Delta antibody (anti-HDV)

Negative

week of testing using the RIA technique can cause
inaccurate results.
Rheumatoid factor and competing IgG-specific
antibody can cause inaccurate positive and negative results.
INDICATIONS FOR HEPATITIS TESTS

Detection of the presence of antigen or antibody
to a specific type of hepatitis depending on symptoms and stage of the disease in the diagnosis of
the condition
Determination of possible hepatitis carrier status
Determination of past exposure or immunity
status in those with a history of hepatitis
Screening of pretransfusion donors for a history
or presence of hepatitis, especially if asymptomatic and information source questionable
Determination of progression to chronic hepatitis
or persistent signs and symptoms of liver dysfunction
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Obtain a thorough history regarding possible
ingestion of contaminated water or foods, environmental sanitation factors conducive to occurrence, recent blood transfusion, parenteral
exposure to materials contaminated by blood or

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Abnormal values: Note and report presence of
antigen or antibody to a specific type of hepatitis.
Provide rest and energy-saving assistance as
needed, skin care for jaundice and pruritus, and
adequate nutritional and fluid intake.
Disease transmission: Note and report type of
hepatitis. If hepatitis A, place client on enteric
precautions. If hepatitis B, C, or D, observe standard precautions for blood-borne pathogens (see
Appendix III for hand protection, personal
protection, and needles and sharps), and instruct
in precautions against transmission via sharing of
needles by IV drug abusers and sexual contact.
Disease prevention: Hepatitis A and B vaccines
for active immunity. Instruct client to avoid
donating blood for 6 months if a transfusion has
been received and to never donate blood if diagnosis of hepatitis B has been made.

ACQUIRED IMMUNODEFICIENCY
SYNDROME TESTS
AIDS and the early stages of HIV infection are
diseases of the immune system caused by the human
immunodeficiency virus or HIV-2. This virus is
responsible for infecting and destroying the T-helper
lymphocytes (CD4 cells). This destruction, in turn,
affects the ability of the body to produce antibodies
and suppresses cellular immune responses, leading
to disorders and infections by many opportunistic
infectious agents. The average time from HIV infection to development of full-blown AIDS is approximately 10 years. The clinical manifestations of the
infection also can vary from an initially mild illness
to an acute state. Those at high risk for the disease
include male homosexuals, hemophiliacs, recipients
of blood or blood products before 1985, and IV drug

CHAPTER 3—Immunology

users who share needles. Heterosexual transmission
of the virus is on the rise.34
After the virus has been acquired, antigens are
detectable in the blood serum as early as 2 weeks,
and they remain for 2 to 4 months. At this time, antibodies appear. Late in the disease, antigens reappear
and antibodies decrease, indicating a poor prognosis. The most common tests to screen for HIV-1
virus antibodies are the EIA, also known as the
enzyme-linked immunosorbent assay (ELISA), and
the immunofluorescence assay. The test is repeated if
the results are positive or borderline. Repeat testing
after a positive value requires confirmation by the
Western immunoblot (WIB) assay, which has the
ability to identify antibodies to at least nine different
epitopes of HIV-1. Antigen testing in the early stages
of HIV-1 infections before antibodies are detected
can be undertaken to monitor clients for progression of the disease and response to therapy. It is also
useful to diagnose HIV-1 infection in infants when
maternal antibodies are passively transferred and
diagnosis based on serologic testing is difficult.35
Reference Values
Negative for HIV antigen by antigen capture
assay during initial infectious state and in
advanced state of the disease
Negative for HIV antibodies by antibody detection methods, EIA, and immunofluorescence
assay
Negative for confirmation test for HIV antibodies by WIB

and Immunologic Testing

INDICATIONS FOR ACQUIRED
IMMUNODEFICIENCY SYNDROME TESTS

Detection of the core p24 protein and antibodies
to the identified protein in the diagnosis and staging or progression of infections in AIDS
Confirmation of positive test results obtained by
EIA to ensure accurate results
Determination of the extent of CD4 (T-helper
lymphocytes) cell decreases in relation to normal
or increased levels of CD8 (T-suppressor) cells to
predict immunodeficiency state
Prediction of exacerbation of the disease by
increased protein 2-microglobulin, indicating
destruction of lymphocytes and macrophages
Assistance in the diagnosis of AIDS in the presence of opportunistic infections determined by
culture and microorganism identification
Screening of those in high-risk groups for the
development of AIDS
Screening of blood donors by blood banks before
obtaining blood donations
Screening of blood before using for transfusion or
preparation of blood products
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Obtain a history regarding possible contact with
the virus such as sexual practices, drug abuse with
needle sharing, transfusion with contaminated
blood products, or presence of pregnancy (virus
could be transmitted to the infant). Inform the
client of confidentiality and legal requirements
regarding the test performance and test results.

INTERFERING FACTORS

Negative results can occur in infected individuals
because of lack of antibody formation early in the
disease and in late stages because of loss of ability
to produce antibodies.
Inaccurate results can occur with the use of test
kits that contain proteins if an individual has been
exposed to the media used in the kits.
Cross-reactive antibodies directed to antigenic
determinants found in nonpathogenic retroviruses can result in inaccurate positive results.36
Children who become infected before birth
through an infected mother can have inaccurate
negative results.
Corticosteroids can affect lymphocyte subset test
results.
Protease inhibitors can inhibit replication of
infected cells and cell-to-cell spread of HIV.

THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped (antigen or antibody) or
lavender-topped (lymphocyte or microglobulin)
tube, depending on the tests to be performed.
Appropriate apparel (gloves and mask) and precautions for blood-borne pathogens are carried out
when obtaining and caring for the blood samples
(see Appendix III).
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Abnormal values: Note and report positive test
results. Inform client of the most current information regarding medications, economic and

SECTION I—Laboratory

Tests

social assistance, and possible psychological counseling services. Instruct client in adequate nutritional and fluid intake. Provide a sensitive,
nonjudgmental, and caring environment for the
client.
Disease transmission: Instruct client in precautions to take during sexual activity; advise to avoid
sharing needles during drug use and to avoid
donating blood. Provide care using standard
precautions and observing transmission-based
isolation procedures for blood-borne pathogens.
Medicolegal aspects: Observe regulations for
confidentiality in reporting test results, such as
use of computer or telephone. Maintain confidentiality of records containing test results. Carry out
state regulation regarding the reporting of positive results. Provide a form for physician to sign
regarding any risks associated with testing and
obtain a signed informed permission request
before the test. Contact Centers for Disease
Control and Prevention (CDC) for the latest
guidelines on reporting HIV status and appropriate follow-up and counseling.

IMMUNOLOGIC TESTS
RELATED TO CANCER
Tumor markers are defined as substances produced
by malignant or benign cells in response to the presence of cancer. They are detected by the examination
of body fluids and tissue specimens. Their use
includes tumor prediction, detection, and identification; monitoring of the course and prognosis; and
evaluation of therapy protocols. The most desirable
markers are those that can detect malignancy in a
remote area by the analysis of body fluids (serum,
urine, fluid from effusion, and CSF) rather than by
invasive procedures to obtain a tissue sample. The
markers are classified as endocrine (hormones),
metabolic consequences associated with tumor
(albumin, blood cells, lipids), enzymes and
isozymes, oncofetal antigens or glycoproteins, and
gene alteration or oncogenes. Current tumor markers and some clinical associations in use at this time
are listed in Table 3–14.37,38 Panels of tumor markers
to assist in the identification or confirmation of a
malignancy in relation to tissue site and to assist in
monitoring the course and prognosis of the malignancy are also performed.
Malignancies or cancer can invade organ tissues,
access vascular channels, and metastasize to other
body sites. They are characterized by an abnormal
number of cells that grow without the normal
control and immune abilities of the body. There is
no single molecular or morphologic characteristic

specific to malignancies.39 This allows for the presence of abnormal reference values associated with
benign cells and conditions other than cancer.
Complete specific test information regarding the
blood cells, enzyme, hormone, endocrine, and metabolic markers listed in Table 3–14 is included in the
respective chapters. These tests are commonly
performed to obtain information about many other
disorders, and differentiation is made when analyzing the results in the diagnosis of malignancy.
Antigens and globulins, used in the diagnosis and
treatment of cancer and commonly found in fetal
life, are considered individually in this section. These
substances are considered abnormal in adults if
present in excessive amounts.

SERUM -FETOPROTEIN TEST
During the first 10 weeks of life, the major serum
protein is not albumin, but -fetoprotein (AFP).
Fetal liver synthesizes huge quantities of AFP until
about the 32nd week of gestation. Thereafter,
synthesis declines until, at 1 year of age, the serum
normally contains no more than 30 ng/mL.
Resting liver cells (hepatocytes) normally manufacture very little AFP, but rapidly multiplying hepatocytes resume synthesis of large amounts.40 Thus,
the test’s greatest usefulness is in monitoring for
recurrence of hepatic carcinoma or metastatic
lesions involving the liver. Note that 30 to 50 percent
of Americans with liver cancer do not have elevated
AFP levels. More consistent elevations are seen in
those Asian and African populations with a very
high incidence of hepatocellular carcinoma.41
Measurement of AFP levels in maternal blood and
amniotic fluid is used to detect certain fetal abnormalities, especially neural tube defects such as anencephaly, spina bifida, and myelomeningocele (see
Chapter 10). Routine prenatal screening includes
determination of the mother’s serum AFP level at 13
to16 weeks of pregnancy. If maternal blood levels are
elevated on two samples obtained 1 week apart, an
ultrasound may be performed, and AFP levels in
amniotic fluid may be analyzed. Other possible
causes of elevated AFP levels during pregnancy
include multiple pregnancy and fetal demise.
INDICATIONS FOR SERUM -FETOPROTEIN TEST

Monitoring for hepatic carcinoma or metastatic
lesions involving the liver, as indicated by highly
elevated levels (e.g., 10,000 to 100,000 ng/mL)
Monitoring for response to treatment for hepatic
carcinoma, with successful treatment indicated by
an immediate drop in levels
Monitoring for recurrence of hepatic carcinoma,

CHAPTER 3—Immunology

TABLE 3–14

•

and Immunologic Testing

Cancer Tests and Tumor Markers

Marker

Clinical Association

Alkaline phosphatase (ALP) (enzyme isozyme)

Osteogenic sarcoma, osteoblastic carcinoma
metastasis

-Fetoprotein (AFP) (oncofetal antigen)

Testicular, hepatic carcinoma

CA 15-3 antigen (oncofetal antigen)

Breast malignancy

CA 19-9 antigen (oncofetal antigen)

Stomach, colon, pancreatic carcinoma

CA 50 antigen (oncofetal antigen)

Stomach, colon, pancreatic carcinoma

CA 125 antigen (oncofetal antigen)

Ovarian, fallopian tube carcinoma

Calcitonin (polypeptide hormone)

Thyroid medullary carcinoma

Carcinoembryonic antigen (CEA) (oncofetal antigen)

Breast, colon, lung carcinoma

Catecholamines (vanillylmandelic acid metabolite)

Neuroblastoma and pheochromocytoma

Creatine kinase isoenzyme (CK-BB) (enzyme isoenzyme)

Breast, pulmonary carcinoma

DU-PAN-2 (glycoprotein antigen)

Pancreatic carcinoma

Galactosyltransferase (GT II) (enzyme isoenzyme)

Pancreatic carcinoma

Genetic mutation (DNA, oncogenes)

Predisposition to development of carcinoma,
leukemia, lymphoma

Human chorionic gonadotropin (hCG) (glycoprotein
hormone)

Testicular carcinoma

5-Hydroxyindoleacetic acid (5-HIAA) (serotonin
metabolite)

Carcinoid tumor

Immunoglobulins produced by B lymphocytes

Multiple myeloma, lymphomas

Lactate dehydrogenase (LD) (enzyme isoenzyme
LD1)

Renal carcinoma, leukemia, lymphoma

Lymphocyte B- and T-cell surface antigens (blood
cell)

Lymphomas, lymphoblastic leukemia

Neuron-specific enolase (NSE) (enolase isoenzyme)

Neuroblastoma, lung carcinoma

Prostate-specific antigen (PSA) (serine protease)

Prostatic carcinoma

Prostatic acid phosphatase (PAP) (enzyme isozyme)

Prostatic carcinoma

Tissue polypeptide antigen (TPA) (oncofetal antigen)

Breast, lung, liver, pancreas, colorectal, stomach,
ovary, prostate, bladder, head and neck, thyroid
carcinoma

Squamous cell carcinoma (SCC) antigen (protein
antigen)

Cervical, lung, esophageal, head and neck carcinoma

Vasoactive intestinal peptide (VIP)

Intestinal tumor

Reference Values

Neonates
1 yr old to adults

Conventional Units

SI Units

600,000 ng/mL

600,000 g/L

30 ng/mL

30 g/L

SECTION I—Laboratory

Tests

with elevated levels occurring 1 to 6 months
before the client becomes symptomatic
Suspected hepatitis or cirrhosis, as indicated by
slightly to moderately elevated levels (e.g., 500
ng/mL)
Routine prenatal screening for fetal neural tube
defects and other disorders, as indicated by
elevated levels
Suspected intrauterine fetal death, as indicated by
elevated levels
Support for diagnosing embryonal gonadal teratoblastoma, hepatoblastoma, and ataxia-telangiectasia

diseases and in smokers (Table 3–15). Although the
test is not diagnostic for any specific disease, it is
used primarily when various types of carcinomas are
suspected.
Reference Values
Less than 2.5 ng/mL

INTERFERING FACTORS

Levels may be elevated in smokers who do not
have malignancies.

NURSING CARE BEFORE THE PROCEDURE

For serum studies, client preparation is the same as
that for any study involving the collection of a
peripheral blood sample (see Appendix I).
For amniotic fluid studies, the client is prepared
for amniocentesis, as described in Chapter 10.
THE PROCEDURE

For serum studies, a venipuncture is performed and
the sample collected in a red-topped tube. The
sample must be handled gently to avoid hemolysis
and transported promptly to the laboratory. For
amniotic fluid studies, amniocentesis is performed
(see Chapter 10).
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedures are the
same as for any study involving collection of a
peripheral blood sample or amniocentesis (see
Chapter 10).
Abnormal adult values: Note and report
increased levels and relate to tissue healing or
regeneration. Assess history for presence or treatment of malignancy; assist in coping with need
for additional treatments.
Abnormal fetal values: Note and report increased
levels in amniotic fluid analysis results or pregnant woman’s serum test results. Assess for fear
and anxiety levels while waiting for test results.
Provide information about genetic counseling,
termination of pregnancy, or both.

CARCINOEMBRYONIC ANTIGEN TEST
Carcinoembryonic antigen (CEA) is a glycoprotein
normally produced only during early fetal life and
during rapid multiplication of epithelial cells, especially those of the digestive system. Elevations of
CEA occur with many cancers, primary and recurrent, as well as with a number of nonmalignant

INDICATIONS FOR CARCINOEMBRYONIC
ANTIGEN TEST

Monitoring of clients with inflammatory intestinal disorders with a high risk of malignancy
Suspected carcinoma of the colon, pancreas, or
lung, because these cancers produce the highest
CEA levels
Monitoring of response to therapy for cancer,
with effective treatment indicated by normal
levels within 4 to 6 weeks
Monitoring for recurrence of carcinoma, with
elevated levels occurring several months before
the client becomes symptomatic
Suspected leukemia, gammopathy, or other disorder associated with elevated CEA levels (see Table
3–15)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving collection of a
peripheral blood sample.
Abnormal values: Note and report increased
values or return of increased values. Assess history
for presence of malignancy and site or treatment
of malignancy. Assist client and family in coping
with need for additional treatments or poor prognosis.

CHAPTER 3—Immunology

TABLE 3–15

•

and Immunologic Testing

Causes of Alterations in CEA Levels
Percentage with CEA Levels, ng/mL

2.5

2.6–5

5.1–10

Nonsmokers

Smokers

Ex-smokers

Colorectal

Pulmonary

Gastric

Breast

Head/neck

Cause of Alteration

Carcinomas

Pancreatic

Other

Leukemias

Lymphoma

Sarcoma

Benign tumors

Benign breast disease

Pulmonary emphysema

Alcoholic cirrhosis

Ulcerative colitis

Regional ileitis

Gastric ulcer

Colorectal polyps

Diverticulitis

CA 15-3, CA 19-9, CA 50, AND CA 125
ANTIGEN TESTS
Cancer antigens are substances detected in serum or
tissue and are defined by one or two monoclonal
antibodies. Immunologic methods are used to detect
the substances in serum and immunohistochemical
methods in tissue. Assay kits for these markers are
available to ensure consistent values among agencies
performing the tests. These tumor markers are not
used for screening malignancy in asymptomatic
populations.
CA 15-3 is a serum antigen defined by two monoclonal antibodies found in breast cancer and breast

cancer metastasis to the liver as well as in benign
diseases of the breast. CA 19-9 is a serum antigen
defined by a monoclonal antibody found in malignancies of the pancreas, gallbladder, salivary glands,
and endocervix as well as in benign disorders such
as acute pancreatitis, inflammatory bowel disease,
and hepatobiliary disease. The test is commonly
performed to monitor the course of a malignancy
that is known to produce the antigen. CA 50 is a
serum antigen defined by a monoclonal antibody
found in pancreatic, colorectal, and gastrointestinal
malignancies. Besides its diagnostic value, CA 50 is
used to monitor the course of a tumor that produces
the antigen.

SECTION I—Laboratory

Tests

Reference Values
Conventional Units

SI Units

CA 15-3

35 U/ml

35 kU/L

CA 19-9

37 U/ml

37 kU/L

CA 50

37 U/ml

37 kU/L

CA 125

35 U/ml

35 kU/L

CA 125 is a serum antigen defined by a monoclonal antibody found in ovarian and pelvic organ
malignancies as well as in breast and pancreatic
malignancies. Nonmalignant conditions such as
ascites of benign cause, pregnancy, menstruation,
endometriosis, and pelvic inflammatory disease also
cause increases in this antigen. The test is undertaken to monitor surgical removal of malignant
ovarian tumor for recurrence and metastasis.
Another test, tissue polypeptide antigen (TPA), is a
marker identified in serum and tissue in those with
a variety of malignancies in relation to the extent of
the disease and subsequent recurrence or regression
after surgical removal of the tumor.42
INTERFERING FACTORS

Chemotherapeutic agents administered to treat
tumor.
Levels can be increased in the absence of disease
or in benign disorders and can affect diagnostic
findings for malignancy.
INDICATIONS FOR CA 15-3, CA 19-9, CA 50,
AND CA 125 ANTIGEN TESTS

Diagnosis and confirmation of presence of local
and metastatic malignancy, suggested by an
increased level or a gradual rise in levels of the
specific cancer antigen
Determination of residual tumor after surgical
intervention to remove the malignancy
Monitoring of course of the malignancy and
effectiveness of therapeutic regimen to determine
progression, prognosis, or recurrence
Differentiation between malignant and benign
disorders of specific organ tissues
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Obtain a history regarding the presence of other
acute or chronic diseases and the assessment data
that support the diagnoses.

Ensure that neoplastic medication protocols are
administered.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be transported promptly to the laboratory for analysis by immunoassay methods.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Abnormal values: Note and report increased
values or return of increased values. Assess for
presence of malignancy site or metastasis or both,
past or ongoing treatments, and procedures for
malignancy. Assist client and family to reduce
anxiety and to cope with need for additional
treatments or poor prognosis.
REFERENCES
1. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, p 63.
2. Winkelstein, A, et al: White Cell Manual, ed 5. FA Davis,
Philadelphia, 1998, p 61.
3. Ibid, pp 61–62.
4. Ibid, p 63.
5. Ibid, pp 63–64.
6. Ibid, pp 68–71.
7. Ibid, p 74.
8. Sacher and McPherson, op cit, pp 242–243.
9. Ibid, p 244.
10. Winkelstein et al, op cit, p 69.
11. Ibid, p 69.
12. Ibid, pp 69–73.
13. Ibid, pp 72–73.
14. Ibid, p 74.
15. Ibid, p 65.
16. Sacher and McPherson, op cit, p 256.
17. Ibid, p 256.
18. Ibid, pp 252–253.
19. Ibid, pp 252–254.
20. Winkelstein et al, op cit, pp 83–84.
21. Sacher and McPherson, op cit, p 253.
22. Ibid, p 246.
23. Ibid, p 246.
24. Ibid, pp 254–255.
25. Ibid, p 255.
26. Ibid, p 262.

CHAPTER 3—Immunology

27.
28.
29.
30.
31.
32.
33.
34.
35.
36.

Ibid, pp 531–532.
Ibid, p 531.
Ibid, p 531.
Ibid, p 532.
Ibid, p 542.
Centers for Disease Control and Prevention, Hepatitis Branch:
Epidemiology and prevention of viral hepatitis A to E: An
overview. CDC, Atlanta, Ga, 1998.
Sacher and McPherson, op cit, pp 441–442.
Ray, CG, and Minnich, LL: Viruses, rickettsia, and chlamydia. In
James, JB: Clinical Diagnosis and Management by Laboratory
Methods, ed 18. WB Saunders, Philadelphia, 1991, p 1249.
Ibid, pp 1249–1250.
Stevens, RW, and McQuillan, GM: Serodiagnosis of human

37.

38.
39.
40.
41.
42.

and Immunologic Testing

immunodeficiency virus (HIV) and hepatitis B virus (HBV) infections. In James, JB: Clinical Diagnosis and Management by
Laboratory Methods, ed 18. WB Saunders, Philadelphia, 1991, pp
913–914.
Rooney, MT, and Henry, JB: Molecular markers of malignant
neoplasms. In James, JB: Clinical Diagnosis and Management by
Laboratory Methods, ed 18. WB Saunders, Philadelphia, 1991, pp
285–286.
Sacher and McPherson, op cit, p 779.
Rooney and Henry, op cit, p 286.
Sacher and McPherson, op cit, pp 437–438.
Ibid, p 438.
Rooney and Henry, op cit, pp 297–298.

CHAPTER

Immunohematology
and Blood Banking
TESTS COVERED
ABO Blood Typing, 96
Rh Typing, 98
Direct Antiglobulin Test, 99

Indirect Antiglobulin Test, 100
Human Leukocyte Antigen Test, 101

INTRODUCTION

Immunohematology is the study of the antigens present on blood cell
membranes and the antibodies stimulated by their presence. For red cells, more than 300 antigenic configurations have been discovered and classified. A specific biologic role has been identified for only a few of these (e.g., ABO and Rh typing for blood transfusions). One
commonality is that blood cell antigens are inherited, and the genes that determine them follow
the laws of mendelian genetics.1 Thus, the greatest usefulness for many of the blood cell antigens that have been identified to date is in genetic studies.
The focus of this chapter is on tests of blood cell antigens and related antibodies that are used
in determining the compatibility of blood and blood products for transfusions.

ABO BLOOD TYPING
The major antigens in the ABO system are A and B.
An individual with A antigens has type A blood; an
individual with B antigens has type B blood. A
person with both A and B antigens has type AB
blood, and one having neither A nor B antigens has
type O blood. The genes determining the presence
or absence of A or B antigens reside on chromosome
number 9.2 Immunologically competent individuals
more than 6 months of age have serum antibodies
that react with the A and B antigens absent from
their own red cells (Table 4–1). Thus, a person with
type A blood has anti-B antibodies, whereas one
with type B blood has anti-A antibodies.
Individuals with type AB blood have neither of
these antibodies, whereas those with type O blood
96

have both. These antibodies are not inherited, but
develop after exposure to environmental antigens
that are chemically similar to red cell antigens (e.g.,
pollens and bacteria). Individuals do not, however,
develop antibodies to their own red cell antigens.3,4
Anti-A and anti-B antibodies are strong agglutinins and cause rapid, complement-mediated
destruction (see Chapter 3) of any incompatible
cells encountered. Although most of the anti-A and
anti-B activity resides in the IgM class of
immunoglobulins (see Chapter 3), some activity
rests with IgG. Anti-A and anti-B antibodies of the
IgG class coat the red cells without immediately
affecting their viability and can readily cross the
placenta, resulting in hemolytic disease of the
newborn. Persons with type O blood frequently
have more IgG anti-A and anti-B antibodies than do

CHAPTER 4—Immunohematology

TABLE 4–1

•

and Blood Banking

Antigens and Antibodies in ABO Blood Groups
Frequency, % in US Populations

Blood
Group

Antigens on
Red Cells

Antibodies
in Serum

Whites

American
Blacks

Native
Americans

Asians

Anti-B

Anti-A

Neither

Anti-A

A and B

Neither

Anti-B

From Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 11. FA Davis,
Philadelphia, 2000, p. 268, with permission.

individuals with type A or B blood. Thus, ABO
hemolytic disease of the newborn (erythroblastosis
fetalis) affects infants of type O mothers almost
exclusively.5
When blood transfusions are required, the client
is normally given blood of his or her own type to
prevent adverse antigen-antibody reactions. In
emergency situations, however, some individuals
may be given blood of other ABO types. For example, because type O blood has neither A nor B antigens, it may be given to individuals with types A, B,
and AB blood. Thus, a person with type O blood is
called a universal donor. With the advent of colloid
expanders (e.g., dextran), untyped blood is not given
even in cases of hemorrhage. Further, because
persons with type O blood have both anti-A and
anti-B antibodies, they can receive only type O
blood.
The situation is reversed for those with type AB
blood. Because these individuals lack anti-A and
anti-B antibodies, they may receive transfusions of
types A, B, and O blood in emergencies when type
AB blood is not available. Thus, a person with type
AB blood is called a universal recipient.
ABO blood typing is an agglutination test in
which the client’s red cells are mixed with anti-A and
anti-B sera, a process known as forward grouping.
The procedure is then reversed, and the person’s
serum is mixed with known type A and type B cells
(i.e., reverse grouping). When a transfusion is to be
administered, cross-matching of blood from the
donor and the recipient is performed along with
typing. Cross-matching detects antibodies in the
sera of the donor and the recipient that could lead to
a transfusion reaction as a result of red cell destruction.
Other pretransfusion or post-transfusion tests
can be performed to determine the cause of transfusion reactions. The leukoagglutinins are antibodies
in the donor blood that react with white blood cells

in the recipient’s blood, producing fever, cough,
dyspnea, and other lung complications, depending
on the severity of the reaction after the transfusion.
Such a reaction requires that leukocyte-poor blood
be used to transfuse these clients. Platelet antibody
tests are performed to detect specific antibodies that
cause post-transfusion purpuric reactions. Assays as
well as platelet typing can be performed to support a
diagnosis of post-transfusion purpura and thrombocytopenic purpura.6
Reference Values
The normal distribution of the four ABO blood
groups in the United States is shown in Table
4–1. Discrepancies in the results of forward and
reverse grouping may occur in infants, elderly
persons, and persons who are immunosuppressed or who have a variety of immunologic
disorders.7
INDICATIONS FOR ABO BLOOD TYPING

Identification of the client’s ABO blood type,
especially before surgery or other procedures in
which blood loss is a threat or for which replacement may be needed, or both
Identification of donor ABO blood type for stored
blood
Determination of ABO compatibility of donor’s
and recipient’s blood types
Identification of maternal and infant ABO blood
types to predict potential hemolytic disease of the
newborn
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Immunosuppressive drugs taken by the client or

SECTION I—Laboratory

Tests

the presence of an immunologic disorder should
be noted.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube or other type of blood
collection tube, depending on laboratory preference.
The sample must be handled gently to avoid hemolysis and sent promptly to the laboratory.
Although correct client identification is important for all laboratory and diagnostic procedures, it
is crucial when blood is collected for ABO typing.
One of the most common sources of error in ABO
typing is incorrect identification of the client and the
specimens.8
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
The client should be informed of his or her blood
type, and the information should be recorded on
a card or other document (e.g., driver’s license)
that the client normally carries in the event of an
emergency requiring a blood transfusion.
Circulatory overload: Report increased blood
pressure; bounding pulse; and signs of pulmonary
edema such as dyspnea, rapid and labored breathing, cough producing blood-stained sputum, and
cyanosis.
Blood transfusion reaction: Note and report
reduced blood pressure, elevated temperature,
chills, palpitations, substernal or flank pain,
warmth at the infusion site, or anxiety. Discontinue transfusion and infuse saline. Send the leftover unit of blood and a blood and urine
specimen to the laboratory.
Critical values: Notify physician immediately if
an incompatible cross-match occurs.

Rh TYPING
After the ABO system, the Rh system is the group of
red cell antigens with the greatest importance.9 The
antigen was called the Rh factor because it was
produced by immunizing guinea pigs and rabbits
with red cells of rhesus monkeys. Researchers found
that the serum from the immunized animals agglutinated not only the rhesus monkey red cells but also
the red cells of approximately 85 percent of humans.
Thus, human red cells could be classified into two
new blood types: Rh-positive and Rh-negative. This
discovery was a great breakthrough in explaining
transfusion reactions to blood that had been tested
for ABO compatibility as well as in explaining

hemolytic disease of the newborn not caused by
ABO incompatibility between mother and fetus.10
We now know that the Rh system includes many
different antigens. The major antigen is termed Rho
or D. Persons whose red cells possess D are called
Rh-positive; those who lack D are called Rh-negative, no matter what other Rh antigens are present,
because the D antigen is more likely to provoke an
antibody response than any other red cell antigen,
including those of the ABO system. The other major
antigens of the Rh system are C, E, c, and e.11 Among
blacks, there are many quantitative and qualitative
variants of the Rh antigens that do not always fit into
the generally accepted classifications.12
Rh-negative individuals may produce anti-D
antibodies if exposed to Rh-positive cells through
either blood transfusions or pregnancy. Although 50
to 70 percent of Rh-negative individuals develop
antibodies if transfused with Rh-positive blood, only
20 percent of Rh-negative mothers develop anti-D
antibodies after carrying an Rh-positive fetus. This
difference occurs because a greater number of cells
are involved in a blood transfusion than are involved
in pregnancy.
When Rh antibodies develop, they are predominantly IgG. Thus, they coat the red cells and set them
up for destruction in the reticuloendothelial system.
The antibodies seldom activate the complement
system (see Chapter 3). Anti-D antibodies readily
cross the placenta from mother to fetus and are the
most common cause of severe hemolytic disease of
the newborn. Immunosuppressive therapy (e.g.,
with Rho[D] immune globulin [RhoGAM]) successfully prevents antibody formation when given to an
unimmunized Rh-negative mother just after delivery or abortion of an Rh-positive fetus.13
Rh typing involves an agglutination test in which
the client’s red cells are mixed with serum containing anti-D antibodies. Agglutination indicates that
the D antigen is present, and the person is termed
Rh-positive.
Reference Values
The D antigen is present on the red cells of 85
percent of whites and a higher percentage of
blacks, Native-Americans, and Asians.

INDICATIONS FOR RH TYPING

Identification of the client’s Rh type, especially
before surgery or other procedures in which
blood loss is a threat or for which replacement
may be needed, or for both

CHAPTER 4—Immunohematology

Identification of donor Rh type for stored
blood
Determination of Rh compatibility of donor’s and
recipient’s blood
Identification of maternal and infant Rh types to
predict potential hemolytic disease of the
newborn
Determination of anti-D antibody titer after
sensitization by pregnancy with an Rh-positive
fetus
Determination of the need for immunosuppressive therapy (e.g., with RhoGAM) when an Rhnegative woman has delivered or aborted an
Rh-positive fetus
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

Care and assessment after the procedure are the
same as that for any study involving the collection of
a peripheral blood sample.
As with ABO typing, the client should be
informed of his or her Rh type.
Women of childbearing age who are Rh-negative
should be informed of the need for follow-up
should pregnancy occur.
Rh incompatibility: Note and report Rh
factors of mother and father, number of pregnancies, and past transfusions of Rh-positive
blood given to an Rh-negative mother.
Communicate incompatible test results to
the physician. Inform client and prepare client
for administration of Rh immunoglobulins
(RhoGAM).

ANTIGLOBULIN TESTS
(COOMBS’ TESTS)
Antiglobulin (Coombs’) tests are used to detect
nonagglutinating antibodies or complement molecules on red cell surfaces. They are used most
commonly in immunohematology laboratories and

and Blood Banking

blood banks for routine cross-matching, antibody
screening tests, and preliminary investigations of
hemolytic anemias.14,15
The tests are based on the principle that
immunoglobulins (i.e., antibodies) act as antigens
when injected into a nonhuman host. This principle
was originally published by Moreschi in 1908, but
his findings drew little notice. In 1945, Coombs
independently rediscovered the principle when he
prepared antihuman serum by injecting human
serum into rabbits. The rabbit antibody produced
against the human globulin was then collected and
purified. This antihuman globulin was used to
demonstrate incomplete human antibodies that
were adsorbed to red cells and did not cause visually
apparent agglutination unless Coombs’ rabbit serum
was used. The two applications of the test currently
used are (1) the direct antiglobulin test (direct
Coombs’) and (2) the indirect antiglobulin test
(indirect Coombs’).16

DIRECT ANTIGLOBULIN TEST
It is never normal for circulating red cells to be
coated with antibody. The direct antiglobulin test
(DAT, direct Coombs’) is used to detect abnormal in
vivo coating of red cells with antibody globulin
(IgG) or complement, or both.
When this test is performed, the red cells are taken
directly from the sample, washed with saline (to
remove residual globulins left in the client’s serum
surrounding the red cells but not actually attached
to them), and mixed with antihuman globulin
(AHG). If the AHG causes agglutination of the
client’s red cells, specific antiglobulins can be used to
determine if the red cells are coated with IgG,
complement, or both.
The most common cause of a positive DAT is
autoimmune hemolytic anemia, in which affected
individuals have antibodies against their own red
cells. Other causes of positive results include
hemolytic disease of the newborn, transfusion of
incompatible blood, and red cell–sensitizing reactions caused by drugs. In the latter, the red cells may
be coated with the drug or with immune complexes
composed of drugs and antibodies that activate the
complement system.17,18 Drugs associated with such
reactions are listed in Table 4–2. Positive DAT results
may also be seen in individuals with Mycoplasma
pneumonia, leukemias, lymphomas, infectious
mononucleosis, lupus erythematosus and other
immune disorders of connective tissue, and metastatic carcinoma. Other conditions, such as the aftermath of cardiac vascular surgery, are associated with
production of autoantibodies.

100

SECTION I—Laboratory

Tests

•

Drugs That May Cause
Positive Results in Direct
Antiglobulin Tests

TABLE 4–2

Cephaloridine
(Loridine)

Penicillin

Cephalothin (Keflin)

Phenytoin (Dilantin)

Chlorpromazine
(Thorazine)

Procainamide
(Pronestyl)

Hydralazine
(Apresoline)

Quinidine

Isoniazid

Rifampin

Levodopa

Streptomycin

Melphalan (Alkeran)

Sulfonamides

Methyldopa (Aldomet)

Tetracycline

Reference Values
Negative (no agglutination)

INTERFERING FACTORS

Many drugs may cause positive reactions (see
Table 4–2).
INDICATIONS FOR DIRECT ANTIGLOBULIN TEST

Suspected hemolytic anemia or hemolytic disease
of the newborn as indicated by a positive reaction
Suspected transfusion reaction as indicated by a
positive result
Suspected drug sensitivity reaction as indicated by
a positive result
NURSING CARE BEFORE THE PROCEDURE

For samples collected by venipuncture, client preparation is the same as that for any study involving the
collection of a peripheral or cord blood sample (see
Appendix I).
Drugs currently taken by the client should be
noted.
If the test is to be performed on the newborn, the
parent(s) should be informed that a sample of
umbilical cord blood will be obtained at delivery
and will not result in blood loss to the infant.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube or other type of
blood collection tube, depending on laboratory
preference. For cord blood, the sample is collected in
a red- or lavender-topped tube (depending on the

laboratory) from the maternal segment of the cord
after it has been cut and before the placenta has been
delivered.
NURSING CARE AFTER THE PROCEDURE

For venipunctures, care and assessment after the
procedure are the same as for any study involving
the collection of a peripheral blood sample.
Complications and precautions: Note and report
a positive value in cord blood of a neonate with
possible erythroblastosis fetalis for direct
Coombs’ because this test result indicates that
antibodies are attached to the circulating erythrocytes. Assess associated bilirubin and hemoglobin
levels. Prepare the infant for exchange transfusion
of fresh whole blood that has been typed and
cross-matched with the mother’s serum.

INDIRECT ANTIGLOBULIN TEST
The indirect antiglobulin test (IAT, indirect
Coombs’, antibody screening test) is used primarily
to screen blood samples for unexpected circulating
antibodies that may be reactive against transfused
red blood cells.
In this test, the client’s serum serves as the source
of antibody, and the red cells to be transfused serve
as the antigen. The test is performed by incubating
the serum and red cells in the laboratory (in vitro) to
allow any antibodies that are present every opportunity to attach to the red cells. The cells are then
washed with saline to remove any unattached serum
globulins, and AHG is added. If the client’s serum
contains an antibody that reacts with and attaches to
the donor red cells, the AHG will cause the antibody-coated cells to agglutinate.
If no agglutination occurs after addition of AHG,
then no antigen-antibody reaction has occurred.
The serum may contain an antibody, but the red
cells against which it is tested do not have the relevant antigen. Thus, the reaction is negative.19
Reference Values
Negative (no agglutination)
INTERFERING FACTORS

Recent administration of dextran, whole blood or
fractions, or intravenous contrast media may
result in a false-positive reaction.
Drugs that may cause false-positive reactions are
cephalosporins, insulin, isoniazid, levodopa,
mefenamic acid, methyldopa, methyldopa hydrochloride, penicillins, procainamide hydrochloride,

CHAPTER 4—Immunohematology

quinidine, rifampin, sulfonamides, and tetracyclines.
INDICATIONS FOR INDIRECT ANTIGLOBULIN TEST

Antibody screening and cross-matching before
blood transfusions, especially to detect antibodies
whose presence may not be elicited by other
methods such as ABO and Rh typing
Determination of antibody titers in Rh-negative
women sensitized by an Rh-positive fetus
Testing for the weak Rh variant antigen D
Detection of other antibodies in maternal blood
that may be potentially harmful to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Exposure to substances that may cause false-positive reactions should be noted. The medication
history should also be noted.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube or other blood collection tube, depending on laboratory preference. The
sample must be handled gently to avoid hemolysis
and sent promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Complications and precautions: Note and report
a positive value for antibody detection, especially
in a pregnant woman. Inform the client that
further testing will be undertaken to identify the
antibodies.

HUMAN LEUKOCYTE ANTIGEN
TEST
All nucleated cells have human leukocyte antigens
(HLA) on their surface membranes. Although sometimes described as “white cell antigens,” HLA characterize virtually all cell types except red blood cells.
HLA consist of a glycoprotein chain and a globulin
chain. They are classified into five series designated
A, B, C, D, and DR (D-related), each series containing 10 to 20 distinct antigens. A, B, C, and D antigens
characterize the membranes of virtually all cells
except mature red blood cells; DR antigens seem to
reside only on B lymphocytes and macrophages (see
Chapter 3).
Some antigens have been identified with specific

and Blood Banking

101

• Diseases Associated with
Human Leukocyte Antigens

TABLE 4–3

Disease

Associated
Antigen

Ankylosing
spondylitis

B27

Reiter’s syndrome

B27

Diabetes mellitus
(juvenile, or
insulin-dependent)
Multiple sclerosis

B8, Bw15
A3, B7, B18

Acute anterior
uveitis

B27

Graves’ disease

Juvenile rheumatoid
arthritis

B27

Celiac disease

Psoriasis vulgaris

B13, Bw17

Myasthenia gravis

Dermatitis herpetiformis

Autoimmune chronic
active hepatitis

diseases (Table 4–3). Arthritic disorders, for example, have been closely linked to HLA-B27. In addition, HLA typing is valuable in determining
parentage. If the HLA phenotypes of a child and one
parent are known, it is possible to assess fairly accurately whether a given individual is the other
parent.20
Reference Values
HLA combinations vary according to certain
races and populations. The most common B
antigens in American whites, for example, are
B7, B8, and B12. In American blacks, the most
common of the B series are Bw17, Bw35, and a
specificity characterized as 1AG. This combination is in contrast to that of African blacks,
whose most common B antigens are B7, Bw17,
and 1AG. Similar variations among the A antigens also have been found among various races
and populations.
INDICATIONS FOR HUMAN LEUKOCYTE
ANTIGEN TESTS

Determination of donor and recipient compatibility for tissue transplantation, especially when
they are blood relatives21

102

SECTION I—Laboratory

Tests

Determination of compatibility of donor platelets
in individuals who will receive multiple transfusions over a long period of time
Support for diagnosing HLA-associated diseases
(see Table 4–3), especially when signs and symptoms are inconclusive
Determination of biologic parentage
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a green-topped tube or other blood
collection device, depending on laboratory preference. The sample is sent promptly to the laboratory
performing the test (not all laboratories are
equipped to do so).
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

Medicolegal implications: HLA testing results for
biologic parentage exclusion are not allowed as
evidence in all jurisdictions.
REFERENCES
1. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, p 265.
2. Ibid, p 266.
3. Harmening, D: Modern Blood Banking and Transfusion Practices,
ed 4. FA Davis, Philadelphia, 2001, p 79.
4. Sacher and McPherson, op cit, pp 268–269.
5. Ibid, p 269.
6. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed 4.
JB Lippincott, Philadelphia, 1992, pp 556–558.
7. Harmening, op cit, p 89.
8. Ibid, p 80.
9. Sacher and McPherson, op cit, p 269.
10. Harmening, op cit, p 105.
11. Sacher and McPherson, op cit, p 271.
12. Harmening, op cit, p 110.
13. Sacher and McPherson, op cit, pp 272–273.
14. Ibid, p 275.
15. Harmening, op cit, pp 65–66.
16. Ibid, pp 65–66.
17. Ibid, p 66.
18. Sacher and McPherson, op cit, p 276.
19. Ibid, p 279.
20. Harmening, op cit, p 374.
21. Ibid, p 369.

CHAPTER

Blood Chemistry
TESTS COVERED
Blood Glucose (Serum Glucose, Plasma
Glucose), 105
Two-Hour Postprandial Blood Glucose
(Postprandial Blood Sugar), 108
Oral Glucose Tolerance Test, 109
Intravenous Glucose Tolerance Test, 111
Cortisone Glucose Tolerance Test, 111
Glycosylated Hemoglobin, 112
Tolbutamide Tolerance Test, 113
Serum Proteins, 114
1-Antitrypsin Test, 116
Haptoglobin, 118
Ceruloplasmin, 119
Urea Nitrogen, 120
Serum Creatinine, 122
Ammonia, 123
Serum Creatine, 123
Uric Acid, 124
Free Fatty Acids, 127
Triglycerides, 128
Total Cholesterol, 130
Phospholipids, 131
Lipoprotein and Cholesterol Fractionation,
133
Lipoprotein Phenotyping, 135
Bilirubin, 137
Alanine Aminotransferase, 140
Aspartate Aminotransferase, 141
Alkaline Phosphatase, 142
5′-Nucleotidase, 144
Leucine Aminopeptidase, 144
-Glutamyl Transpeptidase, 145
Isocitrate Dehydrogenase, 146
Ornithine Carbamoyltransferase, 146
Serum Amylase, 147
Serum Lipase, 148

Acid Phosphatase, 149
Prostate-Specific Antigen, 150
Aldolase, 150
Creatine Phosphokinase and Isoenzymes,
151
Troponin Levels, 154
Lactic Dehydrogenase and Isoenzymes,
155
Hexosaminidase, 156
-Hydroxybutyric Dehydrogenase, 157
Cholinesterases, 157
Renin, 158
Growth Hormone, 161
Growth Hormone Stimulation Tests, 162
Growth Hormone Suppression Test, 163
Prolactin, 163
Adrenocorticotropic Hormone, 164
Thyroid-Stimulating Hormone, 165
TSH Stimulation Test, 166
FSH/LH Challenge Tests, 168
Luteinizing Hormone, 169
Antidiuretic Hormone, 170
Thyroxine, 172
Triiodothyronine, 173
T3 Uptake, 174
Thyroxine-Binding Globulin, 175
Thyroid-Stimulating Immunoglobulins, 175
Calcitonin, 176
Parathyroid Hormone, 176
Cortisol/ACTH Challenge Tests, 178
Aldosterone Challenge Tests, 180
Catecholamines, 181
Estrogens, 182
Progesterone, 183
Testosterone, 184
Human Chorionic Gonadotropin, 185

103

104

SECTION I—Laboratory

Tests

Human Placental Lactogen, 186
Insulin, 188
C-Peptide, 189
Glucagon, 189
Gastrin, 190
Serum Sodium, 191
Serum Potassium, 192
Serum Chloride, 196
Serum Bicarbonate, 198
Serum Calcium, 200

Serum Phosphorus/Phosphate, 202
Serum Magnesium, 204
Serum Osmolality, 206
Arterial Blood Gases, 207
Vitamin A, 210
Vitamin C, 211
Vitamin D, 212
Trace Minerals, 212
Drugs and Toxic Substances, 213

INTRODUCTION

The blood transports innumerable substances that participate in and
reflect ongoing metabolic processes. Relatively few of these substances are routinely measured.
Some materials are analyzed to provide information about specific organs and processes; other
substances reflect the summed effects of numerous metabolic events.1 “Chemistry” includes the
measurement of glucose, proteins, lipids, enzymes, electrolytes, hormones, vitamins, toxins,
and other substances that may indicate derangement of normal physiological processes. In
recent years, the diagnosis of many disorders associated with abnormal blood chemistries has
become more rapid and accurate with the use of automated analyzers that can measure multiple chemistry components in a single blood sample.

CARBOHYDRATES
The body acquires most of its energy from the
oxidative metabolism of glucose. Glucose, a simple
six-carbon sugar, enters the diet as part of the sugars
called sucrose, lactose, and maltose and as the major
constituent of the complex polysaccharides called
dietary starch. Complete oxidation of glucose yields
carbon dioxide (CO2), water, and energy that is
stored as adenosine triphosphate (ATP).
If glucose is not immediately metabolized, it can
be stored in the liver or muscle as glycogen. Unused
glucose can also be converted by the liver into fatty
acids, which are stored as triglycerides, or into
amino acids, which can be used for protein synthesis. The liver is pivotal in distributing glucose as
needed for immediate fuel or as indicated for storage
or for structural purposes. If available glucose or
glycogen is insufficient for energy needs, the liver
can synthesize glucose from fatty acids or even from
protein-derived amino acids.2
Glucose fuels most cell and tissue functions. Thus,
adequate glucose is a critical requirement for homeostasis. Many cells can derive some energy from
burning fatty acids, but this energy pathway is less
efficient than burning glucose and generates acid
metabolites (e.g., ketones) that are harmful if they
accumulate in the body. Many hormones (Table
5–1) participate in maintaining blood glucose levels

in steady-state conditions or in response to stress.
Measures of blood glucose indicate whether the
regulation is successful. Pronounced departure from
normal, either too high or too low, indicates abnormal homeostasis and should initiate a search for the
etiology.3 The causes of abnormal blood glucose
levels are summarized in Table 5–2.
Two major methods are used to measure blood
glucose: chemical and enzymatic. Chemical methods
use the nonspecific reducing properties of the
glucose molecule. In enzymatic methods, glucose
oxidase reacts with its specific substrate, glucose,
liberating hydrogen peroxide, the effects of which
are then measured. Values are 5 to 15 mg/dL higher
for the reducing (chemical) methods than for enzymatic techniques because blood contains other
reducing substances in addition to glucose. Urea, for
example, can contribute up to 10 mg/dL in normal
serum and even more when uremia exists. Several
different indicator systems are used for automated
enzymatic methods, yielding somewhat different
normal values.4
Note also that, in the past, blood glucose values
were given in terms of whole blood. Today, most
laboratories measure serum or plasma glucose
levels. Because of its higher water content, serum
contains more dissolved glucose, and the resultant
values are 1.15 times higher than are those for
whole blood. Serum or plasma should be separated

CHAPTER 5—Blood

TABLE 5–1

Hormone
Insulin

•

Chemistry

105

Hormones That Influence Blood Glucose Levels

Tissue of Origin
Pancreatic cells

Metabolic Effect
1. Enhances entry of glucose into cells

Effect on
Blood
Glucose
Lowers

2. Enhances storage of glucose as glycogen, or
conversion to fatty acids
3. Enhances synthesis of proteins and fatty
acids
4. Suppresses breakdown of protein into amino
acids; of adipose tissue, into free fatty acids
Somatostatin

Pancreatic D cells

1. Suppresses glucagon release from cells
(acts locally)

Lowers

2. Suppresses release of insulin, pituitary tropic
hormones, gastrin, and secretin
Glucagon

Pancreatic cells

1. Enhances release of glucose from glycogen

Raises

2. Enhances synthesis of glucose from amino
acids or fatty acids
Epinephrine

Adrenal medulla

1. Enhances release of glucose from glycogen

Raises

2. Enhances release of fatty acids from adipose
tissue
Cortisol

Adrenal cortex

1. Enhances synthesis of glucose from amino
acids or fatty acids

Raises

2. Antagonizes insulin
Adrenocorticotropic
hormone (ACTH)

Anterior pituitary

1. Enhances release of cortisol

Raises

2. Enhances release of fatty acids from adipose
tissue
Growth hormone

Anterior pituitary

1. Antagonizes insulin

Raises

Thyroxine

Thyroid

1. Enhances release of glucose from glycogen

Raises

2. Enhances absorption of sugars from
intestine
From Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 11. FA Davis,
Philadelphia, 2000, p. 448, with permission.

promptly because red and white blood cells continue
to metabolize glucose. In blood with very high white
blood cell levels, excessive glycolysis may actually
lower glucose results. Arterial, capillary, and venous
blood samples have comparable glucose levels in a
fasting individual. After meals, venous levels are
lower than those in arterial or capillary blood.5

Blood Glucose (Serum Glucose,
Plasma Glucose)
Blood glucose (serum glucose, plasma glucose) is
measured in a variety of situations. In the fasting

state, the serum glucose level gives the best indication of overall glucose homeostasis.6
Blood glucose levels also can be measured at regular intervals throughout the day to monitor
responses to diet and medications in persons with a
diagnosis of abnormalities of glucose metabolism.
Such monitoring may take place in a hospital setting
or in the home with kits specially designed for selfmonitoring of blood glucose. Serial blood glucose
levels also are used to determine insulin requirements in clients with uncontrolled diabetes mellitus
and for individuals receiving total parenteral or
enteral nutritional support.

106

SECTION I—Laboratory

Tests

TABLE 5–2

•

Causes of Altered Blood Glucose Levels

Hyperglycemia

Hypoglycemia
PERSISTENT CAUSES

Diabetes mellitus

Insulinoma

Hemochromatosis

Addison’s disease

Cushing’s syndrome

Hypopituitarism

Hyperthyroidism

Galactosemia

Acromegaly, gigantism

Ectopic insulin production from tumors (adrenal
carcinoma, retroperitoneal sarcomas, pleural
fibrous mesotheliomas)

Obesity
Chronic pancreatitis
Pancreatic adenoma

Starvation
TRANSIENT CAUSES

Pheochromocytoma

Acute alcohol ingestion

Pregnancy (gestational diabetes)

Severe liver disease

Severe glycogen storage diseases

Acute stress reaction

Stress-related catecholamine excess (“functional”
hypoglycemia)

Shock, trauma
Convulsions, eclampsia

Hereditary fructose intolerance

Malabsorption syndrome

Myxedema

Postgastrectomy “dumping syndrome”
DRUGS

Glucagon

Clonidine

Adrenocorticosteroids

Dextrothyroxine

Oral contraceptives

Niacin

Estrogens

Salicylates

Thyroid hormones

Antituberculosis agents

Anabolic steroids

Sulfonylureas

Thiazide diuretics

Sulfonamides

Loop diuretics

Insulin

Propranolol

Ethanol

Antipsychotic drugs

Clofibrate

Hydantoins

MAO inhibitors

In addition to situations characterized by actual
or potential elevations in blood sugar, glucose levels
are evaluated in individuals suspected or known to
have hypoglycemia.

INTERFERING FACTORS

Elevated urea levels and uremia may lead to falsely
elevated levels.

CHAPTER 5—Blood

Chemistry

107

Reference Values
Newborns
Conventional
Units

Children

Adults

SI
Units

Conventional
Units

SI
Units

Conventional
Units

SI
Units

Whole
blood

25–51
mg/dL

1.4–2.8
mmol/L

50–90
mg/dL

2.8–5.0
mmol/L

60–100
mg/dL

3.3–5.6
mmol/L

Serum/
plasma

30–60
mg/dL

1.7–3.3
mmol/L

60–105
mg/dL

3.3–5.8
mmol/L

70–110
mg/dL

3.9–6.1
mmol/L

Critical
values

30 mg/dL
or 300
mg/dL

1.6
mmol/L
or 16.5
mmol/L

40 mg/dL
or 700
mg/dL

2.2
mmol/L
or 38.6
mmol/L

40 mg/dL
or 700
mg/dL

2.2
mmol/L
or 38.6
mmol/L

Note: Values may vary depending on the laboratory method used.

Extremely elevated white blood cell counts may
lead to falsely decreased values.
Failure to follow dietary restrictions before a fasting blood glucose may lead to falsely elevated
values.
Administration of insulin or oral hypoglycemic
agents within 8 hours of a fasting blood glucose
may lead to falsely decreased values.
INDICATIONS FOR BLOOD GLUCOSE TEST

Routine screening for diabetes mellitus:
Fasting blood glucose levels greater than 126
mg/dL on two or more occasions may be
considered diagnostic of diabetes mellitus if
other possible causes of hyperglycemia are
eliminated as sources of elevation (see Table
5–2).
Random (nonfasting) blood glucose levels of
greater than 200 mg/dL may be pathognomonic of diabetes mellitus.7
Clinical symptoms of hypoglycemia or hyperglycemia
Known or suspected disorder associated with
abnormal glucose metabolism (see Table 5–2)
Identification of abnormal hypoglycemia as indicated by a fasting blood sugar as low as 50 mg/dL
in men or 35 mg/dL in women8
Monitoring of response to therapy for abnormal
glucose metabolism
Determination of insulin requirements (i.e.,
“insulin coverage”)
Monitoring of metabolic response to drugs
known to alter blood glucose levels (see Table
5–2)
Monitoring of metabolic response to parenteral
or enteral nutritional support to determine
insulin requirements

NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
If a fasting sample is to be drawn, food and insulin
or any oral hypoglycemic agent should be withheld for approximately 8 hours before the test
(i.e., the client usually takes only water from
midnight until the sample is drawn in the morning).
For home glucose monitoring, the client should
be instructed in the correct use of the testing
equipment and in the method used to obtain the
blood sample.
THE PROCEDURE

A venipuncture is performed and the sample is
obtained in either a gray- or a red-topped tube,
depending on the laboratory performing the test.
The sample should be handled gently to avoid
hemolysis and transported promptly to the laboratory.
A capillary sample may be obtained in infants and
children as well as in adults for whom venipuncture
may not be feasible. Capillary samples also are used
for self-monitoring of blood glucose.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving collection of a
peripheral blood sample.
Resume food and medications withheld before
the test after the sample is drawn.
Abnormal values: Note and report increased
levels. Assess for symptoms associated with hyperglycemia such as polyuria and possible dehydra-

108

SECTION I—Laboratory

Tests

Reference Values
Children

Adults

Elderly Persons

Conventional
Units

SI
Units

Conventional
Units

SI
Units

Conventional
Units

SI
Units

Blood

120 mg/dL

6.6 mmol/L

120 mg/dL

6.6 mmol/L

140 mg/dL

7.7 mmol/L

Serum/
plasma

150 mg/dL

8.3 mmol/L

140 mg/dL

7.7 mmol/L

160 mg/dL

8.8 mmol/L

Note: Values may vary, depending on the laboratory method used.

tion, polydipsia, or weight loss. Prepare for additional glucose tests for diabetes mellitus. Monitor
intake and output (I&O). Prepare to administer
ordered medications (insulin or oral hypoglycemic) to treat known diabetic condition.
Instruct client on diabetic diet in relation to
medications, activities, and blood and urine test
results. Note and report decreased levels. Assess
for symptoms associated with hypoglycemia such
as weakness, sweating, nervousness, hunger,
confusion, or palpitations. Prepare to administer
sucrose or glucose orally or intravenously (IV).
Instruct client to keep readily absorbed carbohydrates on hand. Instruct client on diet and its relation to medications, activities, and blood and
urine test results.
Critical values: Notify the physician immediately of a blood glucose level of less than 30
mg/dL in infants or less than 40 mg/dL in adults
or a blood glucose level of greater than 300
mg/dL in infants or greater than 700 mg/dL in
adults.

Two-Hour Postprandial Blood
Glucose (Postprandial Blood
Sugar)
The 2-hour postprandial blood glucose (postprandial blood sugar, PPBS) test reflects the metabolic
response to a carbohydrate challenge.9 In normal
individuals, the blood sugar returns to the fasting
level within 2 hours.
In contrast, postprandial hypoglycemia appears
to result from delayed or exaggerated response to the
insulin secreted in relation to dietary blood sugar
rise. It may occur as an early event in individuals
with non-insulin-dependent diabetes mellitus
(NIDDM, type II diabetes mellitus) or in individuals
with gastrointestinal malfunction. Frequently, no
cause is demonstrated and the hypoglycemia is
considered “functional.” Postprandial hypoglycemia
differs from fasting hypoglycemia (i.e., hypoglycemia that occurs after 10 or more hours without
food) in that the latter nearly always has pathologi-

cal significance. It results from either overproduction of insulin or undermobilization of glucose and
is most commonly seen in clients with tumors of the
pancreatic cells (insulinoma), liver disease, and
chronic alcohol ingestion.10
With advancing age, the speed of glucose clearance declines. Two-hour levels in persons who do
not have diabetes and in those with negative family
histories may increase an average of 6 mg/dL for
each decade over age 30 years.11
INTERFERING FACTORS

Failing to follow dietary instructions may alter
test results.
Smoking and drinking coffee during the 2-hour
test period may lead to falsely elevated values.
Strenuous exercising during the 2-hour test
period may lead to falsely decreased values.
INDICATIONS FOR 2-HOUR POSTPRANDIAL
BLOOD GLUCOSE (POSTPRANDIAL BLOOD
SUGAR) TEST

Abnormal fasting blood sugar
Routine screening for diabetes mellitus, as indicated by a blood glucose level greater than the
fasting level and especially by a 2-hour level
greater than 200 mg/mL
Identification of postprandial hypoglycemia and
differentiation of this state from fasting hypoglycemia, with fasting hypoglycemia almost
always indicative of a pathological state
Known or suspected disorder associated with
abnormal glucose metabolism (see Table 5–2)
Monitoring of metabolic response to drugs
known to alter blood glucose levels (see Table
5–2)
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
test involving collection of a peripheral blood
sample.
Specific preparation includes ingesting a meal
(usually breakfast) containing at least 100 g of
carbohydrate 2 hours before the test.

CHAPTER 5—Blood

The American Diabetes Association recommends
a 300-g carbohydrate diet for 2 to 3 days before
the test, but this recommendation is not universally followed.
The time of the last meal before the test should be
noted.
The client should then fast from food and avoid
coffee, smoking, and strenuous exercise until the
sample is obtained.
Although medications are not withheld for this
test, those taken should be noted.
THE PROCEDURE

Two hours after the carbohydrate challenge is
ingested, a venipuncture is performed and the
sample is collected in either a gray- or a red-topped
tube, depending on the laboratory performing the
test. A capillary sample may be obtained in children
and in adults for whom venipuncture may not be
feasible. Capillary samples are also used when the
test is performed for mass screenings. Note that in
some instances a fasting blood sugar level may be
obtained before the carbohydrate challenge.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving collection of a
peripheral blood sample. Resume usual diet and
activities.
Complications and precautions: Abnormal
increased or decreased values are treated in the
same way as for blood glucose testing. If the
glucose level does not return to a fasting state
in 2 hours, an additional glucose tolerance test
is required, and there are no critical values to
report.

Glucose Tolerance Tests
Glucose tolerance tests (GTTs) are used to evaluate
the response to a carbohydrate challenge throughout
a 3- to 5-hour period. When a glucose load is
presented, the normal individual’s blood insulin
level rises in response to it, with peak levels occurring 30 to 60 minutes after the carbohydrate challenge. Blood glucose levels, although elevated
immediately after the carbohydrate challenge, return
to normal fasting levels 2 to 3 hours later. For individuals in whom abnormal hypoglycemia or
gastrointestinal malabsorption is suspected, the test
may be extended to a 5-hour period.12–14
Several methods can be used to perform a glucose
tolerance test. The oral, IV, and cortisone glucose
tolerance tests are discussed in this section.
Tolerance tests also may be performed for pentose,
lactose, galactose, and D-xylose.

Chemistry

109

ORAL GLUCOSE TOLERANCE TEST
The oral glucose tolerance test (OGTT) is used for
individuals who are able to eat and who are not
known to have problems with gastrointestinal
malabsorption. The client should be in a normal
nutritional state and should be capable of normal
physical activity (i.e., not immobilized or on bed
rest), because carbohydrate depletion and inactivity
may impair glucose tolerance. In addition, drugs
that affect blood glucose levels (see Table 5–2)
should not be taken for several days before the test.
Because oral glucose tolerance testing is affected by
so many variables, the results are subject to many
diagnostic interpretations.15
The OGTT may be performed using blood
samples only or using urine samples as well. The
urine is normally negative for sugar throughout the
test; that is, because the average renal threshold for
glucose is 180 mg/dL, the plasma glucose level must
be approximately 180 mg/dL before sugar appears in
the urine. Renal threshold levels vary, however, and
urine testing during an OGTT may show how much
glucose the individual spills, if any, at various blood
glucose levels. As long as the renal threshold is not
surpassed by the blood glucose levels, all of the
glucose presented to the kidneys is reabsorbed from
the glomerular filtrate by the renal tubules, provided
that renal function is normal.
INTERFERING FACTORS

Failure to ingest a diet with sufficient carbohydrate content (e.g., 150 g/day) for at least 3 days
before the test may result in falsely decreased
values.
Impaired physical activity may lead to falsely
increased values.
Excessive physical activity before or during the
test may lead to falsely decreased values.
Smoking before or during the test may lead to
falsely increased values.
Ingestion of drugs known to alter blood glucose
levels may lead to falsely increased or decreased
values (see Table 5–2).
INDICATIONS FOR ORAL GLUCOSE TOLERANCE
TEST

Abnormal fasting or postprandial blood glucose
levels that are not clearly indicative of diabetes
mellitus
Identification of impaired glucose metabolism
without overt diabetes mellitus, which is characterized by a modest elevation in blood glucose
after 2 hours and a normal level after 3 hours
Evaluation of glucose metabolism in women of
childbearing age, especially those who are preg-

110

SECTION I—Laboratory

Tests

Reference Values
Time After Carbohydrate Challenge
1 Hr
2 Hr

30 min
Conventional Units

SI
Units

Conventional Units

SI
Units

Conventional Units

SI
Units

3 Hr
ConvenSI
tional Units Units

Whole
blood
glucose

150
mg/dL

8.3
160
mmol/L
mg/dL

8.8
115
mmol/L
mg/dL

Same as
6.6
fastmmol/L
ing

Same as
fasting

Serum/
plasma

160
mg/dL

8.8
170
mmol/L
mg/dL

9.4
125
mmol/L
mg/dL

Same as
7.1
fastmmol/L
ing

Same as
fasting

Urine
Negative throughout test
glucose
Note: Values for children over age 6 years are the same as those for adults. Values for elderly individuals are 10 to 30 mg/dL higher
at each interval because of the age-related decline in glucose clearance.

nant and have a history of previous fetal loss,
birth of babies weighing 9 pounds or more, or
positive family history for diabetes mellitus
Support for diagnosing hyperthyroidism and
alcoholic liver disease, which are characterized by
a sharp rise in blood glucose followed by a decline
to subnormal levels
Identification of true postprandial hypoglycemia
(5-hour GTT) caused by excessive insulin
response to a glucose load
Support for diagnosing gastrointestinal malabsorption, which is characterized by peak glucose
levels lower than that normally expected and
hypoglycemia in the latter hours of the test (5hour GTT)
Identification of abnormal renal tubular function,
if glycosuria occurs without hyperglycemia

Nursing Alert

Individuals with fasting blood sugars of
greater than 150 mg/dL or postprandial blood
glucose levels greater than 200 mg/dL should
not receive the glucose load required for this
test.
If the client vomits the oral glucose preparation, notify the laboratory and physician
immediately, and implement any treatment
ordered.
If signs and symptoms of hypoglycemia are
observed or reported, obtain a blood sugar
immediately and administer orange juice with
1 tsp of sugar or other beverage containing
sugar; notify the physician that the test has
been terminated.

NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The general procedure for the test, including the
administration of glucose and the frequency of
collection of blood and urine samples
The importance of eating a diet containing at least
150 g carbohydrate per day for 3 days before the
test (Provide sample menus or lists of foods that
demonstrate how this may be accomplished.)
Which medications, if any, are to be withheld
before the test
That no food may be eaten after midnight before
the test but that water is not restricted
The importance of not smoking or performing
strenuous exercise after midnight before the test
and until the test is completed
The symptoms of hypoglycemia and the necessity
of reporting such symptoms immediately

Provide containers for collection of urine
samples.
THE PROCEDURE

A venipuncture is performed and a sample is
obtained for a fasting blood sugar. At the same time,
a second voided (double-voided) urine sample is
collected and tested for glucose. To collect a secondvoided specimen, have the client void 30 minutes
before the required specimen is due. Discard this
urine, then collect the second voided specimen at the
designated time.
The glucose load is administered orally. This is a
calculated dose, either 1.75 g/kg body weight or 50
g/m2 body surface. Several commercial preparations
are available that are flavored for palatability. Blood

CHAPTER 5—Blood

and urine samples are obtained at 1/2-hour, 1-hour,
2-hour, and 3-hour intervals. The second voided
urine specimen is necessary only at the beginning
of the test. The client should drink one glass of
water each time a urine sample is collected to
ensure adequate urinary output for remaining
specimens. If the test is extended to 5 hours, additional samples are collected at 4- and 5-hour intervals.
The test may be performed with blood samples
only, depending on the desired information to be
obtained from the test.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are essentially the same as those for any test involving the
collection of peripheral blood samples.
Resume food and medications withheld before
the test, as well as usual activities.
Complications and precautions: Same as for
blood glucose. Closely monitor those clients
whose pretest levels are greater than 200 mg/dL
for possible reactions to the additional glucose
intake required for the test.

INTRAVENOUS GLUCOSE TOLERANCE
TEST
The intravenous glucose tolerance test (IVGTT) is
essentially the same as the OGTT, except that the
carbohydrate challenge is administered IV instead of
orally. Because the results are somewhat difficult to
interpret, the IVGTT is used only in certain clinical
situations or for research purposes.
Reference Values
The reference values are the same as those for
the OGTT, except that the blood glucose level at
the 1/2-hour interval may be 300 to 400 mg/dL
because of the direct IV administration of the
glucose load.
INTERFERING FACTORS

Those factors that may alter the results of an
OGTT may also alter the results of an IVGTT.
Infusions of total parenteral nutrition (TPN,
hyperalimentation) during the test may lead to
falsely elevated values; alternative solutions with
less glucose should be infused for at least 3 hours
before and during the test.
INDICATIONS FOR INTRAVENOUS GLUCOSE
TOLERANCE TEST

Inability to take or tolerate oral glucose preparations used for the OGTT

Chemistry

111

Suspected gastrointestinal malabsorption problems that interfere with accurate performance of
the OGTT
Evaluation of blood glucose control without the
effects of gastrin, secretin, cholecystokinin, and
gastric inhibitory peptide, all of which stimulate
insulin production after oral ingestion of glucose
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
the OGTT.
If the person is receiving TPN, an alternative solution with less glucose should be prescribed and
infused for at least 3 hours before and during the
test.
THE PROCEDURE

The procedure is essentially the same as that for the
OGTT except that an intermittent venous access
device (e.g., heparin lock) may be inserted to administer the glucose load and to obtain blood samples.
Existing IV lines also may be used to administer the
carbohydrate challenge, which is usually 50 percent
glucose, with the amount to be given determined by
the client’s weight or body surface.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for the OGTT.
If an intermittent venous access device was
inserted for the procedure, remove it after
completion of the test and apply a pressure bandage to the site.
Resume food and medications withheld before
the test, as well as usual activities.
Resume infusions of TPN as ordered.

CORTISONE GLUCOSE TOLERANCE
TEST
The cortisone glucose tolerance test (cortisone
GTT) combines administration of a carbohydrate
challenge with a cortisone challenge. Cortisone
enhances the synthesis of glucose from amino acids
and fatty acids (gluconeogenesis) and, when administered with a glucose load, may produce an abnormal GTT that would not otherwise be evident. The
cortisone GTT is used only in certain clinical situations and for research purposes.
Reference Values
The reference values are similar to those for the
OGTT except that the blood glucose level at the
2-hour interval may be 20 mg/dL higher than
the client’s fasting level.

112

SECTION I—Laboratory

Tests

INTERFERING FACTORS

Those factors that may alter the results of an
OGTT may also alter the results of a cortisone
GTT.
Failure to administer or take the oral cortisone as
prescribed for the test will alter results.
INDICATIONS FOR CORTISONE GLUCOSE
TOLERANCE TEST

Inconclusive results of OGTT when prediabetes
or “borderline” diabetes is suspected, with a 2hour level of greater than 165 mg/dL considered
indicative of diabetes
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
the OGTT.
In addition, the client should be instructed on the
purpose and administration of the oral cortisone
acetate.
THE PROCEDURE

The procedure is the same as that for the OGTT
except that cortisone acetate is administered orally 8
hours and again 2 hours before the standard GTT is
begun.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for the OGTT.

Glycosylated Hemoglobin
Throughout the red blood cell’s life span, the hemoglobin molecule incorporates glucose onto its
chain. Glycosylation is irreversible and occurs at a
stable rate. The amount of glucose permanently
bound to hemoglobin depends on the blood sugar
level. Thus, the level of glycosylated hemoglobin,
designated Hgb A1c, reflects the average blood sugar
over a period of several weeks.
The test is used to evaluate the overall adequacy of
diabetic control and provides information that may
be missed by individual blood and urine glucose
tests. Insulin-dependent diabetics, for example, may
have undetected periods of hyperglycemia alternating with postinsulin periods of normoglycemia or
even hypoglycemia. High Hgb A1c levels reflect inadequate diabetic control in the preceding 3 to 5 weeks.
In addition to providing a more accurate assessment of overall blood glucose control, the test is
more convenient for diabetic clients because it is
performed only every 5 to 6 weeks and because there
are no dietary or medication restrictions before the
test.

Reference Values
Hgb A1c is 3 to 6 percent of hemoglobin.
Hgb A1c is 7 to 11 percent in diabetes under
control.
INTERFERING FACTORS

Individuals with hemolytic anemia and high
levels of young red blood cells may have spuriously low levels.
Individuals with elevated hemoglobin levels or on
heparin therapy may have falsely elevated levels.
INDICATIONS FOR GLYCOSYLATED
HEMOGLOBIN TEST

Monitoring overall blood glucose control in
clients with known diabetes, because the test aids
in assessing blood glucose levels over a period of
several weeks and provides data that may be
missed by random blood or urine glucose tests:
With prolonged hyperglycemia, levels of Hgb
A1c may rise to as high as 18 to 20 percent.
After normoglycemic levels are stabilized, Hgb
A1c levels return to normal in about 3 weeks.16
Monitoring adequacy of insulin dosage for blood
glucose control, especially that administered by
automatic insulin pumps
Evaluating the diabetic client’s degree of compliance with the prescribed therapeutic regimen,
because fasting or adjusting medications shortly
before the test will not significantly alter results
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving collection of a peripheral blood sample
(see Appendix I).
The client should be informed that fasting or
adjusting medications for diabetes shortly before
the test will not significantly alter results.
THE PROCEDURE

A venipuncture is performed and the sample
obtained in a lavender-topped tube. The sample
must be mixed adequately with the anticoagulant
contained in the tube and transported promptly to
the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving collection of a
peripheral blood sample.
Complications and precautions: A value of
greater than 15 percent of total Hgb A1c indicates
that the diabetes is out of control. Notify the
physician at once.

CHAPTER 5—Blood

Chemistry

113

Tolbutamide Tolerance Test

NURSING CARE BEFORE THE PROCEDURE

Tolbutamide (Orinase) is a hypoglycemic agent that
produces hypoglycemia by stimulating the cells of
the pancreas to secrete and release insulin. An IV
infusion of tolbutamide raises the serum insulin and
causes a rapid decrease in the blood glucose level.
Thus, the test demonstrates the pancreatic -cell
response to drug-induced stimulation. Note that the
test can be performed with glucagon or leucine
instead of tolbutamide for clients who are sensitive
to sulfonylureas or sulfonamides.

Client preparation is essentially the same as that for
an OGTT.
The individual should be informed that venous
access will be established with either a continuous
infusion or an intermittent device and that a
medication that lowers blood sugar will be
administered.
The client should be questioned regarding allergies to sulfonylureas or sulfonamides.
Clients with a history of abnormal hypoglycemia
will need reassurance that they will be monitored
closely during the test.

Reference Values
A decrease in serum glucose levels is evident
within 5 to 10 minutes of administration of the
drug. The lowest glucose levels occur in about 20
to 30 minutes and are generally about half of the
client’s usual fasting level. The glucose level
returns to pretest values in 1 to 3 hours.
INTERFERING FACTORS

The factors that may alter the results of an OGTT
may also alter the results of a tolbutamide tolerance test.
INDICATIONS FOR TOLBUTAMIDE TOLERANCE
TEST

Evaluation of fasting or postprandial hypoglycemia by assessing the degree of pancreatic cell response to drug-induced stimulation
Suspected insulinoma (insulin-producing tumor
of the pancreatic cells) as indicated by glucose
levels that drop markedly in response to tolbutamide and take 3 or more hours to return to
normal levels
Suspected prediabetic state that may be characterized by excessive insulin release, as indicated by
glucose levels that are lower than expected but
that follow the overall pattern of a normal
response to the test
Nursing Alert

Because of the expected drop in blood sugar
levels, the test should be performed with
extreme caution, if at all, on individuals with
fasting blood sugars of 50 mg/dL or less.
If the client is allergic to sulfonylureas or
sulfonamides, the test should be performed
using glucagon or leucine instead of tolbutamide.

THE PROCEDURE

Venous access is established and a sample is obtained
for a fasting blood sugar (FBS). The IV catheter is
then connected to an intermittent device (e.g.,
heparin lock) or to a continuous IV infusion of
normal saline at a keep-vein-open (KVO) rate.
Tolbutamide 1.0 g mixed in 20 mL sterile water is
administered IV. Blood glucose samples are obtained
via the IV catheter at 15-minute intervals for the first
hour and then at 11/2-, 2-, and 3-hour intervals.
Observe the client closely for signs and symptoms of
hypoglycemia. If hypoglycemia occurs, obtain a stat
FBS, notify the physician, and initiate an IV infusion
of 5 percent glucose and water, if ordered.
Note any signs or symptoms of sensitivity reaction to tolbutamide. If a reaction occurs, notify the
physician and administer drugs as ordered. Maintain
an open IV line until there is no further danger of
adverse drug reaction.
NURSING CARE AFTER THE PROCEDURE

The venous access device is left in place until any
danger of hypoglycemia is past. It is then removed
and a pressure bandage applied to the site. Food
and medications withheld before the test, as well
as usual activities, should be resumed on its completion.
Continue to observe for signs and symptoms of
hypoglycemia for 2 hours or more, depending on
results of the 3-hour interval blood sugar.
Assess the venipuncture site for signs of
hematoma or phlebitis.
Observe for adequate intake when foods are
resumed.

PROTEINS
Proteins, also called polypeptides, consist of amino
acids linked by peptide bonds. Although all human
proteins are constructed from a mere 20 amino
acids, variations in chain length, amino acid

114

SECTION I—Laboratory

Tests

sequence, and incorporated constituents combine to
make possible an almost infinite number of protein
molecules. All cells manufacture proteins, with
different proteins characterizing different cell types.
The amino acids needed for these processes enter the
body from dietary sources. These amino acids are
rapidly distributed to tissue cells, which promptly
incorporate them into proteins.
Three-fourths of the body’s solid matter is protein
and, except for hemoglobin, relatively little circulates
in whole blood. The major plasma proteins are albumin, the globulins, and fibrinogen. Fibrinogen
evolves into insoluble fibrin when blood coagulates.
The fluid that remains after coagulation is called
serum. Serum and plasma have the same protein
composition except that serum lacks fibrinogen and
several other coagulation factors (prothrombin,
factor VIII, factor V, and factor XIII).
The proteins in circulating blood transport amino
acids from one site to another, providing raw materials for synthesis, degradation, and metabolic interconversion. Circulating proteins also function as
buffers in acid–base balance, contribute to the maintenance of colloidal osmotic pressure, and aid in
transporting lipids, enzymes, hormones, vitamins,
and certain minerals.
Most plasma proteins originate in the liver.
Hepatocytes synthesize fibrinogen, albumin, and
TABLE 5–3

•

60 to 80 percent of the globulins. The remaining
globulins are immunoglobulins (antibodies), which
are manufactured by the lymphoreticular system.
Immunoglobulins are studied as part of the immune
system (see Chapter 3), whereas fibrinogen is
usually studied as part of a coagulation workup
(see Chapter 2). The focus of this section is on the
major serum proteins (albumin and nonantibody
globulins), binding proteins, and protein metabolites.17

Serum Proteins
General assessment of the serum proteins includes
measurement of total protein, albumin, globulin,
and the albumin-to-globulin (A-G) ratio. Although
these tests are being replaced by serum protein electrophoresis (see Chapter 3), they may still be ordered
for screening purposes or as components of multitest chemistry profiles, because they provide an
overall picture of protein homeostasis.
Several disorders can cause alterations in serum
proteins. Those affecting total protein levels are
listed in Table 5–3. Albumin levels show less variation. Except for dehydration, exercise, and effects
of certain drugs (e.g., gallamine triethiodide
[Flaxedil]), elevated albumin levels do not occur.
Albumin may be decreased in a number of situations

Causes of Altered Total Serum Proteins

Increased Levels

Decreased Levels

Kala-azar

Renal disease

Dehydration

Ulcerative colitis

Macroglobulinemias

Water intoxication

Sarcoidosis

Cirrhosis
Severe burns

Drugs

Scleroderma

Adrenocorticotropic hormone, corticosteroids

Malnutrition

Clofibrate

Hodgkin’s disease

Dextran

Hemorrhage

Growth hormone
Heparin

Drugs

Insulin

Ammonium ion

Sulfobromophthalein (Bromsulphalein, BSP)

Dextran

Thyroid preparations

Oral contraceptives

Tolbutamide

Pyrazinamide

X-ray contrast media

Salicylates

CHAPTER 5—Blood

caused, in general, by (1) decreased hepatic synthesis, (2) excessive renal excretion, (3) increased metabolic degradation, and (4) complex combined
disorders. Specific problems associated with hypoalbuminemia are listed in Table 5–4.
Globulin levels show more variation than do
albumin levels, probably because of the multiple
production sites for this protein. Causes of altered
globulin levels are listed in Table 5–5 according to
the type of globulin affected.
The A-G ratio indicates the balance between total
albumin and total globulin and is usually evaluated
in relation to the total protein level. A low protein
level and a reversed A-G ratio (i.e., decreased albumin and elevated globulins) suggest chronic liver
disease. A normal total protein level with a reversed
A-G ratio suggests myeloproliferative disease (e.g.,
leukemia, Hodgkin’s disease) or certain chronic
infectious diseases (e.g., tuberculosis, chronic hepatitis).
INTERFERING FACTORS

High serum lipid levels may interfere with accurate testing.
Numerous drugs may alter protein levels (see
Tables 5–3 and 5–4).
INDICATIONS FOR SERUM PROTEINS TEST

Routine screening as part of a complete physical
examination, with normal results indicating satisfactory overall protein homeostasis
Clinical signs of diseases associated with altered
serum proteins (see Tables 5–3, 5–4, and 5–5)
Monitoring of response to therapy with drugs
that may alter serum protein levels

Chemistry

• Causes of
Hypoalbuminemia

TABLE 5–4

Decreased Synthesis of Albumin
Malnutrition (starvation, malabsorption iron
deficiency)
Chronic diseases (tuberculosis)
Acute infections (hepatitis, brucellosis)
Chronic liver disease
Collagen disorders (scleroderma, systemic lupus
erythematosus)
Drugs
Acetaminophen (Tylenol)
Azathioprine (Imuran)
Conjugated estrogens (Premarin)
Cyclophosphamide (Cytoxan)
Dextran
Ethinyl estradiol (Estinyl)
Heroin
Mestranol/norethynodrel (Enovid)
Niacin
Nicotinyl alcohol (Roniacol)
Increased Loss of Albumin
Ascites
Burns (severe)
Nephrotic syndrome
Chronic renal failure

NURSING CARE BEFORE THE PROCEDURE

Increased Catabolism of Albumin

Client preparation is the same as that for any test
involving collection of a peripheral blood sample
(see Appendix I).
Some laboratories require an 8-hour fast before
the test, as well as a low-fat diet for several days
before the test, because high serum lipid levels
may interfere with accurate testing.

Malignancies (leukemias, advanced tumors)

THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently and sent promptly to the laboratory.

Trauma
Multifactorial Causes
Cirrhosis
Congestive heart failure
Pregnancy
Toxemia of pregnancy
Diabetes mellitus
Myxedema
Rheumatic fever

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving collection of a

115

Rheumatoid arthritis
Hypocalcemia

116

SECTION I—Laboratory

TABLE 5–5
Globulin
1

Tests

•

Causes of Altered Serum Globulin Levels
Increased Levels

Decreased Levels

Pregnancy

Genetic deficiency of
1-antitrypsin

Malignancies
Acute infections
Tissue necrosis
2

Acute infections

Hemolytic anemia

Trauma, burns

Severe liver disease

Advanced malignancies
Rheumatic fever
Rheumatoid arthritis
Acute myocardial infarction
Nephrotic syndrome

Hypothyroidism

Hypocholesterolemia

Biliary cirrhosis
Nephrotic syndrome
Diabetes mellitus
Cushing’s syndrome
Malignant hypertension

Connective tissue diseases (such
as systemic lupus erythematosus
and rheumatoid arthritis)

Nephrotic syndrome

Hodgkin’s disease

Lymphosarcoma

Chronic active liver disease

Drugs

Lymphocytic leukemia

Bacille Calmetté-Guérin
vaccine

Tolazamide (Tolinase)
Tubocurarine

Methotrexate

Anticonvulsants

peripheral blood sample. Resume any foods withheld before the test.
Abnormal values: Note and report increased
levels. Assess for symptoms of dehydration that
can cause hyperproteinemia such as thirst, dry
skin and mucous membranes, or poor skin turgor.
Assess fluid loss resulting from vomiting, diarrhea, or renal dysfunction. Note and report
decreased levels. Assess in relation to hypoalbuminuria and for edema in serum albumin levels as
low as 2.0 to 2.5 g/dL. Assess for causes of hypoalbuminemia such as acute or chronic liver disease
or renal dysfunction. Assess for stress, injury, or
infection that requires increased protein intake.
Prepare for IV administration of albumin replace-

ment in severe conditions. Monitor I&O.
Encourage and instruct in increased dietary
protein intake.

1-Antitrypsin Test
1-Antitrypsin (1-AT) is an 1-globulin produced
by the liver. Its function is inhibition of the proteolytic enzymes trypsin and plasmin, which are
released by alveolar macrophages and by bacteria in
the lungs. As with many other proteins, the 1-AT
molecule has several structural variants. Some of
these variant molecules have different electrophoretic mobility and reduced ability to inhibit
proteolytic enzymes.

CHAPTER 5—Blood

Chemistry

117

Reference Values
The reference values for total protein, albumin, and globulin vary slightly across the life cycle and are listed
accordingly. Values for -globulins are provided for comparison purposes.
Total Protein

Albumin

-Globulins

Globulins

Conventional Units

SI
Units

Conventional Units

SI
Units

Newborns

5.0–7.1
g/dL

50–70 g/L

2.5–5.0
g/dL

25–50 g/L

1.2–4.0
g/dL

12–40
g/dL

0.7–0.9
g/dL

7–9 g/L

3 mo

4.7–7.4
g/dL

47–74 g/L

3.0–4.2
g/dL

30–42 g/L

1.0–3.3
g/dL

10–33
g/L

0.1–0.5
g/dL

1–5 g/L

1 yr

5.0–7.5
g/dL

50–75 g/L

2.7–5.0
g/dL

27–50 g/L

2.0–3.8
g/dL

20–38
g/L

0.4–1.2
g/dL

4–12 g/L

15 yr

6.5–8.6
g/dL

65–86 g/L

3.2–5.0
g/dL

32–50 g/L

2.0–4.0
g/dL

20–40
g/L

0.6–1.2
g/dL

6–12 g/L

Adults

6.6–7.9
g/dL

66–79 g/L

3.3–4.5
g/dL

33–45 g/L

2.0–4.2
g/dL

20–42
g/L

0.5–1.6
g/dL

5–16 g/L

Age

ConvenSI
Conventional Units Units tional Units

SI
Units

A-G ratio 1.5:1–2.5:1
Although discussed in Chapter 3, the normal values for serum protein electrophoresis are repeated next
for reference purposes. Values are reported as percentage of total proteins.
Total Globulins
Conventional
Units
52–68

SI
Units
0.520–

Albumin
Conventional
Units
32–48

0.680

SI
Units
0.320–
0.480

Conventional
Units
10.7–
21.0

2
SI
Units

0.107–
0.210

Inherited deficiencies in normal 1-AT activity
are associated with the development, early in life, of
lung and liver disorders in which functional tissue is
destroyed and replaced with excessive connective
tissue; that is, emphysema and cirrhosis may develop
in children and young adults who are deficient in 1AT, without the usual predisposing factors associated
with onset of these disorders. Such deficiencies are
seen on serum protein electrophoresis as a flat area
where the normal 1-globulin hump should be.
More detailed physiochemical analysis can demonstrate which variant form is present. Decreased levels
of 1-AT also are seen in nephrotic syndrome and
malnutrition.
Reference Values
80 to 213 mg/dL
INTERFERING FACTORS

Pregnancy

Conventional
Units
8.5–

SI
Units

0.085–

14.5

0.145

Conventional
Units
6.6–
13.5

SI
Units

0.066–

Conventional
Units
2.4–5.3

0.135

SI
Units
0.024–
0.053

Oral contraceptive and steroid administration
Extreme physical stress caused by trauma or
surgery
INDICATIONS FOR 1-ANTITRYPSIN TEST

Genetic absence or deficiency of 1-AT, indicated
by decreased levels of the protease
Suspected inflammation, infection, and necrosis
processes, indicated by increased levels of the
protease
Family history of 1-AT deficiency
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving collection of a peripheral blood sample
(see Appendix I).
The client should fast for 8 hours before the test.
Water is not restricted.
Oral contraceptives and steroids should be withheld 24 hours before the study, although this practice should be confirmed with the person
ordering the test.

118

SECTION I—Laboratory

Tests

THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and frozen if
not tested immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume meals or medications withheld before the
test.
Abnormal values: Note and report decreased
levels. Assess for pulmonary or liver disorders and
associated signs and symptoms, smoking history,
and pollution in the home or work environment.
Inform client of stop-smoking clinics and
resources for genetic counseling. Instruct client in
ways to protect pulmonary system from irritants.
Inform client of the importance of medical
follow-up. Suggest ongoing support resources to
assist client in coping with illness and possible
early death.

Binding Proteins
HAPTOGLOBIN
Haptoglobin, an 2-globulin produced in the liver,
binds free hemoglobin released by the hemolysis
of red blood cells in the bloodstream. Most red
blood cells are normally removed in the reticuloendothelial system (e.g., liver, spleen) by a process
known as extravascular destruction. Approximately
10 percent of red blood cells are, however, broken
down in the circulation (intravascular destruction).
This percentage may increase in situations caused by
excessive red blood cell hemolysis (e.g., transfusion
reaction, hemolytic anemia).
The free hemoglobin released from intravascular
red blood cell destruction is unstable in plasma and
dissociates into components (- dimers) that are
quickly bound to haptoglobin. Formation of the
haptoglobin–hemoglobin complex prevents the
renal excretion of plasma hemoglobin and stabilizes
the heme-globin bond. The haptoglobin–hemoglobin complex is removed from the circulation by the
liver.
There is a limit to the capacity of the haptoglobinbinding mechanism, and a sudden intravascular
release of several grams of hemoglobin can exceed
binding capacity. Furthermore, because haptoglobin
itself is removed from the circulation as a haptoglobin–hemoglobin complex and is catabolized by the

liver, a decrease in or absence of haptoglobin may be
used to indicate increased intravascular red blood
cell hemolysis.
Because haptoglobin is formed in the liver,
chronic liver disease with impaired protein synthesis
also may result in decreased haptoglobin levels.
Although haptoglobin is absent in most newborns,
congenital absence of haptoglobin (congenital ahaptoglobinemia) can occur in a very small percentage
of the population.
If haptoglobin is deficient or its binding capacity
overwhelmed, unbound hemoglobin dimers are free
to be filtered by the renal glomerulus, after which
they are reabsorbed by the renal tubules and
converted into hemosiderin (a storage form of iron).
If renal tubular uptake capacity is exceeded, either
free hemoglobin or methemoglobin (a type of
hemoglobin with iron in the ferric, instead of the
ferrous, form) is excreted in the urine. Note that
reabsorption of free hemoglobin may damage the
renal tubules because of excessive deposition of
hemosiderin.18
Elevated haptoglobin levels are seen in inflammatory diseases (e.g., ulcerative colitis, arthritis,
pyelonephritis) and in disorders involving tissue
destruction (e.g., malignancies, burns, acute
myocardial infarction). Steroid therapy may also
elevate haptoglobin levels. Elevated levels are not of
major clinical significance except to indicate that
additional testing may be necessary to determine the
source of the elevation.
Reference Values
Conventional Units

SI Units

Newborns

0–10 mg/dL

0–0.1 g/L

Adults

30–160 mg/dL

0.3–1.6 g/L

INTERFERING FACTORS

Steroid therapy may result in elevated levels.
INDICATIONS FOR HAPTOGLOBIN TEST

Known or suspected disorder characterized by
excessive red blood cell hemolysis, as indicated by
decreased levels
Known or suspected chronic liver disease, as indicated by decreased levels
Suspected congenital ahaptoglobinemia, as indicated by decreased levels
Known or suspected disorders involving a diffuse
inflammatory process or tissue destruction, as
indicated by elevated levels

CHAPTER 5—Blood

TABLE 5–6

•

Chemistry

119

Causes of Altered Levels of Ceruloplasmin

Increased Levels
Acute infections

Decreased Levels
Wilson’s disease

Hepatitis

Malabsorption syndromes

Hodgkin’s disease

Long-term total parenteral nutrition

Hyperthyroidism

Menkes’ kinky hair syndrome

Pregnancy

Nephrosis

Malignancies of bone, lung, stomach

Severe liver disease

Myocardial infarction

Early infancy

Rheumatoid arthritis
Drugs
Oral contraceptives
Estrogens
Methadone
Phenytoin (Dilantin)

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. Some laboratories
require that the sample be placed in ice immediately
upon collection. The sample should be handled
gently to avoid hemolysis, which may alter test
results, and sent promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

CERULOPLASMIN
Ceruloplasmin (Cp) is an 2-globulin that binds
copper for transport within the circulation after it is
absorbed from the gastrointestinal tract. Among the
disorders associated with abnormal ceruloplasmin
levels is Wilson’s disease (hepatolenticular degeneration), an inherited disorder characterized by excessive absorption of copper from the gastrointestinal
tract, decreased ceruloplasmin, and deposition of
copper in the liver, brain, corneas (Kayser-Fleischer
rings), and kidneys. In addition to low ceruloplasmin levels, serum copper levels are decreased

because of excessive excretion of unbound copper in
the kidneys and deposition of copper in the body
tissues. The disorder manifests during the first three
decades of life and is fatal unless treatment is instituted.
Other causes of abnormal ceruloplasmin levels
are listed in Table 5–6.
Reference Values
Conventional Units

SI Units

Newborns

2–13 mg/dL

20–130 mol/L

Adults

23–50 mg/dL

230–500 mol/L

INDICATIONS FOR CERULOPLASMIN TEST

Family history of Wilson’s disease (hepatolenticular degeneration)
Signs of liver disease combined with neurological
changes, especially in a young person, with
Wilson’s disease indicated by decreased levels
Monitoring of ceruloplasmin levels in disorders
associated with abnormal values (see Table 5–6)
Monitoring of response to TPN (hyperalimentation), which may lead to decreased levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving collection of a peripheral blood sample
(see Appendix I).

120

SECTION I—Laboratory

Tests

THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. Some laboratories
require that the sample be placed in ice immediately
on collection. The sample should be handled gently
to avoid hemolysis and sent promptly to the laboratory.

nitrogen; the result is expressed as urea nitrogen.
Nitrogen contributes 46.7 percent of the total weight
of urea. The concentration of urea can be calculated
by multiplying the urea nitrogen result by 2.14.19
INTERFERING FACTORS

Therapy with drugs known to alter urea nitrogen
levels (see Table 5–7)

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Abnormal values: Note and report decreased
levels. Assess for hepatic or neurological or
psychiatric manifestations of Wilson’s disease.
Assess for history of ceruloplasmin deficiency by
Kayser-Fleischer rings determined by slit-lamp
examination. Inform of need for follow-up
medical care and genetic counseling.

INDICATIONS FOR UREA NITROGEN TEST

Known or suspected disorder associated with
impaired renal function, as indicated by increased
levels:
Obstructive, inflammatory, or toxic damage to
the kidneys, nephron loss caused by aging, or
extrarenal conditions that reduce the glomerular filtration rate (GFR) increase retention of
urea.
Monitoring for the effects of disorders associated
with altered fluid balance:
Dehydration or hypovolemia caused by vomiting, diarrhea, hemorrhage, or inadequate fluid
intake raises the urea nitrogen.
Fluid overload decreases the urea nitrogen if
renal function is adequate.
Known or suspected liver disease as indicated by
decreased levels caused by the liver’s inability to
convert ammonia to urea (80 percent of liver
function may be lost before this is evident)
Monitoring for effects of drugs known to be
nephrotoxic or hepatotoxic
Monitoring of response to various disorders
known to result in altered urea nitrogen levels (see
Table 5–7)

Protein Metabolites
Most nitrogen in the blood resides in proteins, and
the amount of nitrogen contained in proteins is high
in relation to amino acid content. When proteins are
metabolized, the nitrogen-containing components
are removed from the amino acids, a process known
as deamination. The resulting protein metabolites
include urea, creatinine, ammonia, creatine, and uric
acid. Levels of these nonprotein nitrogenous
compounds reflect various aspects of protein
balance and metabolism.

UREA NITROGEN
Urea is a nonprotein nitrogenous compound that is
formed in the liver from ammonia. Although urea
diffuses freely into both extracellular and intracellular fluid, it is ultimately excreted by the kidneys.
Blood urea levels reflect the balance between
production and excretion of urea. Changes in
protein intake, fluid balance, liver function, and
renal excretion affect blood urea levels. Specific
causes of alterations are listed in Table 5–7.
Blood urea analysis involves measurement of

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving collection of a peripheral blood sample
(see Appendix I).
Some laboratories require an 8-hour fast before
the test.
THE PROCEDURE

A venipuncture is performed and the sample is
obtained in either a gray-topped or red-topped tube,

Reference Values
Conventional Units [Urea Nitrogen]

SI Units [Urea]

Newborns

4–18 mg/dL

1.4–6.4 mmol/L

Children

7–18 mg/dL

2.5–6.4 mmol/L

Adults

5–20 mg/dL

1.8–7.1 mmol/L

Critical values

100 mg/dL

35.7 mmol/L

CHAPTER 5—Blood

TABLE 5–7

•

Chemistry

Causes of Altered Urea Levels

Increased Levels

Decreased Levels

Congestive heart failure

Inadequate dietary protein

Shock

Severe liver disease

Hypovolemia

Water overload

Urinary tract obstruction

Nephrotic syndrome

Renal diseases

Pregnancy

Starvation

Amyloidosis

Infection

Malabsorption syndromes

Myocardial infarction

Drugs

Diabetes mellitus

IV dextrose

Burns

Phenothiazines

Gastrointestinal bleeding

Thymol

Advanced pregnancy
Nephrotoxic agents
Excessive protein ingestion
Malignancies
Addison’s disease
Gout
Pancreatitis
Tissue necrosis
Advanced age
Drugs
Aspirin
Acetaminophen
Cancer chemotherapeutic agents
Antibiotics (amphotericin B, cephalosporins, aminoglycosides)
Thiazide diuretics
Indomethacin (Indocin)
Morphine
Codeine
Sulfonamides
Methyldopa (Aldomet)
Propranolol (Inderal)
Guanethidine (Ismelin)
Pargyline (Eutonyl)
Lithium carbonate
Dextran
Sulfonylureas

121

122

SECTION I—Laboratory

Tests

depending on the laboratory performing the test.
The sample should be handled gently to avoid
hemolysis and transported promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
If the client’s diet was restricted before the test, the
usual diet may be resumed.
Abnormal levels: Note and report decreased
levels. Assess hydration status for overhydration,
I&O, osmolality, and sodium levels. Note and
report increased levels and assess in relation to
creatinine level. Assess electrolyte panel and for
signs and symptoms of anemia, gastrointestinal
bleeding, oliguria, confusion, and level of
consciousness if urea nitrogen rises to greater
than 20 to 50 mg/dL. Monitor urinary output
every hour. Provide safety measures if consciousness is altered. Instruct as to restriction in fluid
and dietary intake of protein (meat, fish, poultry).

Daily generation of creatinine remains fairly
constant unless crushing injury or degenerative
diseases cause massive muscle damage. The kidneys
excrete creatinine very efficiently. Levels of blood
and urine flow affect creatinine excretion much less
than they influence urea excretion because temporary alterations in renal blood flow and glomerular
function can be compensated by increased tubular
secretion of creatinine. Thus, serum creatinine is a
more sensitive indicator of renal function than is
urea nitrogen.20
INDICATIONS FOR SERUM CREATININE TEST

Critical values: Notify the physician immediately if levels are greater than 100 mg/dL.

SERUM CREATININE
Creatinine is the end product of creatine metabolism. Creatine, although synthesized largely in the
liver, resides almost exclusively in skeletal muscle,
where it reversibly combines with phosphate to form
the energy storage compound phosphocreatine. This
reaction (creatine
phosphate ←
→ phosphocreatine) repeats as energy is released and regenerated,
but in the process small amounts of creatine are irreversibly converted to creatinine, which serves no
useful function and circulates only for transportation to the kidneys. The amount of creatinine generated in an individual is proportional to the mass of
skeletal muscle present; level of muscular activity is
not a critical determinant.

Known or suspected impairment of renal
function, including therapy with nephrotoxic
drugs:
In the absence of disorders affecting muscle
mass, elevated creatinine levels indicate
decreased renal function.
Creatinine levels may be normal in situations
in which a slow decline in renal function occurs
simultaneously with a slow decline in muscle
mass, as may occur in elderly individuals (in
such situations, a 24-hour urine collection
yields lower than normal excretion levels).
Along with a urea nitrogen, to provide additional
client information:
An elevated urea nitrogen with a normal creatinine usually indicates a nonrenal cause for the
excessive urea.
The urea nitrogen rises more steeply than creatinine as renal function declines, and it falls
more rapidly with dialysis.
With severe, permanent renal impairment, urea
levels continue to climb, but creatinine values
tend to plateau (at very high circulating creatinine levels, some is excreted through the
gastrointestinal tract).
Known or suspected disorder involving muscles,
including crushing injury to muscles:
In the absence of renal disease, elevated serum
creatinine levels are associated with trauma or

Reference Values
Conventional Units

SI Units

Children 6 yr

0.3–0.6 mg/dL

24–54 mol/L

Children 6–18 yr

0.4–1.2 mg/dL

36–106 mol/L

Men

0.6–1.3 mg/dL

53–115 mol/L

Women

0.5–1.0 mg/dL

44–88 mol/L

Critical values

10 mg/dL

880 mol/L

Adults

CHAPTER 5—Blood

disorders causing excessive muscle mass
(gigantism, acromegaly).
Decreased levels are associated with muscular
dystrophy.
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving collection of a peripheral blood sample
(see Appendix I).
Some laboratories require an 8-hour fast before
the test.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be sent promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Complications and precautions: Increased levels
should be assessed in relation to the urea nitrogen;
notify the physician immediately if levels are greater than 10 mg/dL unless the client is on dialysis.

AMMONIA
Blood ammonia comes from two sources: (1) deamination of amino acids during protein metabolism
and (2) degradation of proteins by colon bacteria.
The liver converts ammonia to urea, generating glutamine as an intermediary. The kidneys then use
glutamine as a source for synthesizing ammonia for
renal regulation of electrolyte and acid–base
balance. Serum ammonia levels have little effect on
renal excretion of ammonia.
Circulating blood normally contains very little
ammonia because the liver converts ammonia in the
portal blood to urea. When liver function is severely
compromised, especially in situations when
decreased hepatocellular function is combined with
impaired portal blood flow, ammonia levels rise.
Both elevated serum ammonia and abnormal glutamine metabolism have been implicated as etiologic
factors in hepatic encephalopathy (hepatic coma).21
Additional causes of altered serum ammonia levels
are listed in Table 5–8.
Reference Values
Conventional Units

Chemistry

123

INDICATIONS FOR SERUM AMMONIA TEST

Evaluation of advanced liver disease or other
disorders associated with altered serum ammonia
levels (see Table 5–8)
Identification of impending hepatic encephalopathy in clients with known liver diseases (e.g., after
bleeding from esophageal varices or other
gastrointestinal sources, or after excessive ingestion of protein) as indicated by rising levels
Monitoring for the effectiveness of treatment for
hepatic encephalopathy as indicated by declining
levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I). An 8-hour fast from
food is required before the test.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a green-topped tube. Some laboratories
require that the sample be placed in ice immediately
on collection. The sample should be handled gently
to avoid hemolysis and sent promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample. Resume foods withheld
before the test.

SERUM CREATINE
Creatine is a nitrogen-containing compound found
largely in skeletal muscle, where it functions as an
energy source. Its use by muscles results in loss
proportionate to the muscle mass and level of
muscular activity. Measurement of serum creatine
reflects this loss, which is fairly constant under
normal conditions.
Reference Values
Conventional Units

SI Units

Men

0.1–0.4 mg/dL

9–35 mol/L

Women

0.2–0.7 mg/dL

18–62 mol/L

SI Units

Newborns

90–150 g/dL

64–107 mol/L

Children

40–80 g/dL

23–47 mol/L

Adults

15–45 g/dL

11–32 mol/L

INTERFERING FACTORS

Failure to follow dietary restrictions and vigorous
exercise within 8 hours of the test may alter
results.

124

SECTION I—Laboratory

TABLE 5–8

Tests

•

Causes of Altered Blood Ammonia Levels

Increased Levels

Decreased Levels

Liver failure, late cirrhosis

Renal failure

GI hemorrhage

Hypertension

Late congestive heart failure
Drugs
Azotemia

Arginine (R-Gene)

Hemolytic disease of the newborn

Benadryl

Chronic obstructive pulmonary disease

Sodium salts

Leukemias

Glutamic acid (Acidulin)

Reye’s syndrome

MAO inhibitors

Inborn enzyme deficiency

Antibiotics (tetracycline [Achromycin],
kanamycin [Kantrex], neomycin)

Excessive protein ingestion

Potassium salts

Alkalosis
Drugs
Acetazolamide (Diamox)
Ammonium salts
Barbiturates
Colistin (Coly-Mycin S)
Diuretics
Ethanol
Heparin
Isoniazid
Methicillin
Morphine
Tetracycline

INDICATIONS FOR SERUM CREATINE TEST

Signs and symptoms of muscular disease (e.g.,
muscle injury, muscular dystrophies, dermatomyositis), as indicated by elevated levels
Monitoring for the progression of muscle-wasting
diseases with serial measurements indicating the
rate of muscle deterioration
Evaluation of the effects of hyperthyroidism and
rheumatoid arthritis on muscle tissue
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
Food, fluids, and vigorous exercise are not permitted for at least 8 hours before the test.

THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and sent
promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of a
peripheral blood sample.
Resume foods and fluids withheld before the test,
as well as usual activities.

URIC ACID
Uric acid (urate) is the end product of purine
metabolism. Purines are important constituents of

CHAPTER 5—Blood

Chemistry

125

Reference Values
Conventional Units

SI Units

Children

2.5–5.5 mg/dL

0.15–0.33 mmol/L

Men

4.0–8.5 mg/dL

0.24–0.51 mmol/L

Women

2.7–7.3 mg/dL

0.16–0.43 mmol/L

Critical values

12 mg/dL

0.71 mmol/L

nucleic acids; purine turnover occurs continuously
in the body, producing substantial amounts of uric
acid even in the absence of dietary purine (e.g.,
meats, legumes, yeasts) intake. Most uric acid is
synthesized in the liver and excreted by the kidneys.
Serum urate levels are affected by the amount of uric
acid produced as well as by the efficiency of renal
excretion.
Both gout and urate renal calculi (kidney stones)
are associated with elevated uric acid levels. Other
disorders and drugs associated with altered uric acid
levels are listed in Table 5–9.
INTERFERING FACTORS

Therapy with drugs known to alter uric acid levels
(see Table 5–9), unless the test is being conducted
to monitor such drug effects
INDICATIONS FOR URIC ACID TEST

Family history of gout (autosomal dominant
genetic disorder) or signs and symptoms of gout,
or both, with the disorder indicated by elevated
levels
Known or suspected renal calculi, to determine
the cause
Signs and symptoms of disorders associated with
altered uric acid levels (see Table 5–9)
Monitoring for the effects of drugs known to alter
uric acid levels (see Table 5–9), either as a side
effect or as a therapeutic effect
Evaluation of the extent of tissue destruction in
infection, starvation, excessive exercise, malignancies, chemotherapy, or radiation therapy
Evaluation of possible liver damage in eclampsia,
as indicated by elevated levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Some laboratories require an 8-hour fast from
food before the test.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should

be handled gently to avoid hemolysis and sent
promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume foods withheld before the test.
Abnormal values: Note and report increased
level. Assess for symptoms associated with renal
stones and joint pain. Prepare to administer
ordered medications (allopurinol, probenecid,
nonsteroidal anti-inflammatory analgesics).
Increase fluid intake. Instruct client to avoid highpurine fluids and foods (sardines, organ meats,
legumes, alcohol, caffeine-containing beverages).
Critical values: Notify the physician immediately if levels are greater than 12 mg/dL.

LIPIDS
Lipids are carbon- and hydrogen-containing
compounds that are insoluble in water but soluble in
organic solvents. Biologically important categories
of lipids are the neutral fats (e.g., triglycerides), the
conjugated lipids (e.g., phospholipids), and the
sterols (e.g., cholesterol). Lipids function in the body
as sources of energy for various metabolic processes.
Other functions include contributing to the formation of cell membranes, bile acids, and various
hormones.
Lipids are derived from both dietary sources and
internal body processes. Almost the entire fat
portion of the diet consists of triglycerides, which
are combinations of three fatty acids and one glycerol molecule. Triglycerides are found in foods of
both animal and plant origin. The usual diet also
includes small quantities of phospholipids, cholesterol, and cholesterol esters. Phospholipids and
cholesterol esters contain fatty acids. In contrast,
cholesterol does not contain fatty acids, but its sterol
nucleus is synthesized from their degradation products. Because cholesterol has many of the physical
and chemical properties of other lipids, it is included
as a dietary fat. Note that cholesterol occurs only in
foods of animal origin, including eggs and cheese.

126

SECTION I—Laboratory

Tests

TABLE 5–9

•

Causes of Altered Uric Acid Levels

Increased Levels

Decreased Levels

Excessive dietary purines

Fanconi’s syndrome

Polycythemia

Wilson’s disease

Gout

Yellow atrophy of the liver

Psoriasis

Drugs

Type III hyperlipidemia

Probenecid

Chemotherapy, radiation therapy for malignancies

Sulfinpyrazone

von Gierke’s disease

Aspirin (4 g/day)

Sickle cell anemia

Adrenocorticotropic hormone,
corticosteroids

Pernicious anemia

Coumarin

Acute tissue destruction (infection, starvation, exercise)

Estrogens

Eclampsia, hypertension

Allopurinol

Hyperparathyroidism

Acetohexamide (Dymelor)

Decreased excretion from lactic acidosis, ketoacidosis, renal
failure, congestive heart failure

Azathioprine (Imuran)

Drugs

Clofibrate

Alcohol

2-Phenylcinchoninic acid (Cinchophen)

Aspirin (2 g/day)

Chlorprothixene (Taractan)

Thiazide diuretics

Mannitol

Diazoxide (Hyperstat)

Marijuana

Epinephrine
Ethacrynic acid (Edecrin)
Furosemide
Phenothiazines
Dextran
Methyldopa
Ascorbic acid
Aminophylline
Antibiotics (gentamicin)
Griseofulvin
Rifampin
Triamterene (Dyrenium)

Nearly all dietary fats are absorbed into the
lymph. Ingested triglycerides are emulsified by bile
and then broken down into fatty acids and glycerol
by pancreatic and enteric lipases. The fatty acids and
glycerol then pass through the intestinal mucosa and
are resynthesized into triglycerides that aggregate
and enter the lymph as minute droplets called

chylomicrons. Although chylomicrons are
composed primarily of triglycerides, cholesterol and
phospholipids absorbed from the gastrointestinal
tract also contribute to their composition (Table
5–10).
In addition to dietary sources of lipids, the body
itself is able to produce various fats. Unused glucose

CHAPTER 5—Blood

TABLE 5–10
Triglyceride
%

•

Chemistry

127

Lipoprotein Composition

Cholesterol Phospholipid
%
%

Protein
%

Electrophoretic
Mobility

Chylomicrons

85–95

3–5

5–10

1–2

Remain at origin

Very-low-density
lipoproteins

60–70

10–15

2-Lipoprotein, pre--lipoprotein

Low-density
lipoproteins

5–10

20–30

15–25

-Lipoprotein

High-density
lipoproteins

Very little

1-Lipoprotein

From Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 11. FA Davis,
Philadelphia, 2000, p. 473, with permission.

and amino acids, for example, may be converted into
fatty acids by the liver. Similarly, nearly all body cells
are capable of forming phospholipids and cholesterol, although most of the endogenous production
of these lipids occurs in the liver or intestinal
mucosa.
Because lipids are insoluble in water, special
transport mechanisms are required for circulation in
the blood. Free fatty acids travel through blood
combined with albumin and in this form are called
nonesterified fatty acids. Very little free fatty acid is
normally present in the blood; therefore, the major
lipid components found in serum are triglycerides,
cholesterol, and phospholipids. These lipids exist in
blood as macromolecules complexed with specialized proteins (apoproteins) to form lipoproteins.
Lipoproteins are classified according to their
density, which results from the amounts of the various lipids they contain (see Table 5–10). The least
dense lipoproteins are those with the highest triglyceride levels. Lipoprotein densities also are reflected
in the electrophoretic mobility of the various types.
As with the formation of other endogenous lipids,
most lipoproteins are formed in the liver.22,23

FREE FATTY ACIDS
Free fatty acids (FFA) travel through the blood
combined with albumin and in this form are called
nonesterified fatty acids (NEFA). Normally, approximately three fatty acid molecules are combined with
each molecule of albumin. If, however, the need for
fatty acid transport is great (e.g., when needed
carbohydrates are not available or cannot be used for
energy), as many as 30 fatty acids can combine with
one albumin molecule. Thus, although blood levels
of FFA are never very high, they rise impressively
after stimuli to release fat. The same stimuli that
elevate FFA will, in most cases, also elevate serum
triglycerides and may produce alterations in
lipoprotein levels. Specific causes of both elevated

and decreased FFA, including drugs, are listed in
Table 5–11.
Reference Values
Conventional Units
Free fatty
acids

8–25 mg/dL

SI Units

0.30–0.90 mmol/L

INTERFERING FACTORS

Ingestion of alcohol within 24 hours before the
test may result in falsely elevated values.
Failure to follow dietary restrictions before the
test may alter values.
Drugs known to alter FFA levels should not be
ingested unless the test is being performed to evaluate such effects (see Table 5–11).
INDICATIONS FOR FREE FATTY ACIDS TEST

Support for diagnosing uncontrolled or untreated
diabetes mellitus, as indicated by elevated levels
Evaluation of response to treatment for diabetes,
as indicated by declining levels
Suspected malnutrition, as indicated by elevated
levels
Known or suspected disorder associated with
excessive hormone production (see Table 5–11),
as indicated by elevated levels
Evaluation of response to therapy with drugs
known to alter FFA levels (see Table 5–11)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
The client should abstain from alcohol for 24
hours and from food for at least 8 hours before
the test.
Water is not restricted.

128

SECTION I—Laboratory

Tests

•

Factors Associated
with Altered Free Fatty
Acid Levels

TABLE 5–11

Increased Levels

Decreased Levels

Diabetes mellitus

Drugs

Starvation

Aspirin

Pheochromocytoma

Clofibrate

Acute alcohol intoxication

Glucose

Chronic hepatitis

Insulin

Acute renal failure

Neomycin

Glycogen storage disease

Streptozocin

Hypoglycemia
Hypothermia
Hormones
Adrenocorticotropic hormone
Cortisone
Epinephrine, norepinephrine
Growth hormone
Thyroid-stimulating hormone
Thyroxine
Drugs

Abnormal values: Note and report any increased
level. Assess in relation to glucose and ketone and
to lipid and lipoprotein electrophoresis levels.
Assess for recent weight gain or loss. Instruct in
appropriate fat and carbohydrate intake in the
diet.

TRIGLYCERIDES
Triglycerides, which are combinations of three fatty
acids and one glycerol molecule, are used in the body
to provide energy for various metabolic processes,
with excess amounts stored in adipose tissue. Fatty
acids readily enter and leave the triglycerides of
adipose tissue, providing raw materials needed for
conversion to glucose (gluconeogenesis) or for
direct combustion as an energy source. Although
fatty acids originate in the diet, many also derive
from unused glucose and amino acids that the liver
and, to a smaller extent, the adipose tissue convert
into storage energy.
Altered triglyceride levels are associated with a
variety of disorders and also are affected by
hormones and certain drugs, including alcohol
(Table 5–12). Diets high in calories, fats, or carbohydrates will elevate serum triglyceride levels, which is
considered a risk factor for atherosclerotic cardiovascular disease.
Reference Values

Amphetamines
Caffeine

Conventional Units

SI Units

Chlorpromazine

2 yr

5–40 mg/dL

0.06–0.45 mmol/L

Isoproterenol

2–20 yr

10–140 mg/dL

0.11–1.58 mmol/L

Nicotine

20–40 yr
Men

10–140 mg/dL

0.11–1.58 mmol/L

Women

10–150 mg/dL

0.11–1.68 mmol/L

Men

10–180 mg/dL

0.11–2.01 mmol/L

Women

10–190 mg/dL

0.11–2.21 mmol/L

Reserpine
Tolbutamide

40–60 yr
Drugs known to affect FFA levels (see Table 5–11)
may be withheld before the test, although this may
not always be done if the therapeutic effect on
FFA levels is being evaluated.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be sent immediately to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume foods and any drugs withheld before
the test.

Note: Values for serum triglycerides may vary according to
the laboratory performing the test. In addition, values
have been found to vary in relation to race, income level,
level of physical activity, dietary habits, and geographic
location as well as in relation to age and gender, as shown
here.
INTERFERING FACTORS

Failure to follow the usual diet for 2 weeks before
the test may yield results that do not accurately
reflect client status.
Ingestion of alcohol 24 hours before and food 12
hours before the test may falsely elevate levels.

CHAPTER 5—Blood

TABLE 5–12

•

Chemistry

129

Disorders and Drugs Associated with Altered
Triglyceride Levels

Elevated Levels

Decreased Levels
DISORDERS

Primary hyperlipoproteinemia

Acanthocytosis

Atherosclerosis

Cirrhosis

Hypertension

Inadequate dietary protein

Myocardial infarction

Hyperthyroidism

Diabetes mellitus

Hyperparathyroidism

Obstructive jaundice
Hypothyroidism (primary)
Hypoparathyroidism
Nephrotic syndrome
Chronic obstructive pulmonary disease
Down syndrome
von Gierke’s disease
DRUGS

Alcohol

Clofibrate

Cholestyramine

Dextrothyroxine

Corticosteroids

Heparin

Colestipol

Menotropins (Pergonal)

Oral contraceptives

Sulfonylureas

Thyroid preparations

Norethindrone

Estrogen

Androgens

Furosemide

Niacin

Miconazole

Anabolic steroids
Ascorbic acid

Drugs known to alter triglyceride levels should
not be ingested within 24 hours before the test
unless the test is being conducted to evaluate such
effects (see Table 5–12).
INDICATIONS FOR SERUM TRIGLYCERIDES TEST

As a component of a complete physical examination, especially for individuals over age 40 years
or who are obese, or both, to estimate the
degree of risk for atherosclerotic cardiovascular
disease
Family history of hyperlipoproteinemia (hyperlipidemia)
Known or suspected disorders associated with
altered triglyceride levels (see Table 5–12)

Monitoring of response to drugs known to alter
triglyceride levels or lipid-lowering agents
NURSING CARE BEFORE THE PROCEDURE

130

SECTION I—Laboratory

Tests

the test, although this practice should be
confirmed with the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be sent promptly to the laboratory.

INTERFERING FACTORS

Ingestion of alcohol 24 hours before and food 12
hours before the test may falsely elevate levels.
Ingestion of drugs known to alter cholesterol
levels within 12 hours of the test may alter results,
unless the test is being conducted to evaluate such
effects (see Table 5–13).

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume foods and any drugs withheld before the
test.
Abnormal values: Note and report increased
level. Assess in relation to cholesterol and lipoprotein electrophoresis. Instruct in low-fat diet and
weight reduction caloric intake as appropriate.

TOTAL CHOLESTEROL
Cholesterol is necessary for the formation of cell
membranes and is a component of the materials that
render the skin waterproof. Cholesterol also
contributes to the formation of bile salts, adrenocorticosteroids, estrogens, and androgens.
Cholesterol has two sources: (1) that obtained
from the diet (exogenous cholesterol) and (2) that
which is synthesized in the body (endogenous
cholesterol). Although most body cells can form
some cholesterol, most is produced by the liver and
the intestinal mucosa. Because cholesterol is continuously synthesized, degraded, and recycled, it is
probable that very little dietary cholesterol enters
directly into metabolic reactions. Altered cholesterol
levels are associated with a variety of disorders and
also are affected by hormones and certain drugs
(Table 5–13).
Reference Values

INDICATIONS FOR TOTAL CHOLESTEROL TEST

As a component of a complete physical examination, especially for individuals over age 40 years or
those who are obese, or both, to estimate the
degree of risk for atherosclerotic cardiovascular
disease:
In general, the desirable blood cholesterol level
is less than 200 mg/dL.
Cholesterol levels of 200 to 240 mg/dL are
considered borderline, and the person is
considered at high risk if other factors such as
obesity and smoking are present; for the latter
individuals, additional tests such as lipoprotein
and cholesterol fractionation should be
performed.
Cholesterol levels of greater than 250 mg/dL
place the person at definite high risk for cardiovascular disease and require treatment; additional tests such as lipoprotein and cholesterol
fractionation should be performed.
Family history of hypercholesterolemia or cardiovascular disease or both
Known or suspected disorders associated with
altered cholesterol levels (see Table 5–13)
Monitoring of response to dietary treatment of
hypercholesterolemia and support for decisions
regarding need for drug therapy (Cholesterol
levels may fall with diet modification alone over a
period of 6 months, only to return gradually to
previous levels.)
Monitoring for response to drugs known to alter
cholesterol levels (see Table 5–13) or lipid-lowering agents

Conventional Units

SI Units

25 yr

125–200 mg/dL

3.27–5.20 mmol/L

NURSING CARE BEFORE THE PROCEDURE

25–40 yr

140–225 mg/dL

3.69–5.85 mmol/L

40–50 yr

160–245 mg/dL

4.37–6.35 mmol/L

50–65 yr

170–265 mg/dL

4.71–6.85 mmol/L

65 yr

175–265 mg/dL

4.71–6.85 mmol/L

General client preparation is the same as that for any
procedure involving collection of a peripheral blood
sample (see Appendix I).
For this test, the client should abstain from alcohol for 24 hours and from food for 12 hours
before the study.
Water is not restricted.
It also is recommended that drugs that may alter
cholesterol levels be withheld for 12 hours before
the test, although this practice should be
confirmed with the person ordering the study.

Note: Values for total cholesterol may vary according to the
laboratory performing the test. In addition, values have
been found to vary according to gender, race, income
level, level of physical activity, dietary habits, and
geographic location as well as in relation to age, as shown
here.

CHAPTER 5—Blood

TABLE 5–13

•

Chemistry

131

Disorders and Drugs Associated with Altered
Cholesterol Levels

Elevated Levels

Decreased Levels
DISORDERS

Familial hyperlipoproteinemia

Malabsorption syndromes

Atherosclerosis

Liver disease

Hypertension

Hyperthyroidism

Myocardial infarction

Cushing’s syndrome

Obstructive jaundice

Pernicious anemia

Hypothyroidism (primary)

Carcinomatosis

Nephrosis
Xanthomatosis
Pregnancy
Oophorectomy
DRUGS

Adrenocorticotropic hormone

Antidiabetic agents

Androgens

Cholestyramine

Bile salts

Clofibrate

Catecholamines

Colchicine

Corticosteroids

Colestipol

Oral contraceptives

Dextrothyroxine

Phenothiazines

Estrogen

Salicylates

Glucagon

Thiouracils

Haloperidol (Haldol)

Vitamins A and D (excessive)

Heparin
Kanamycin
Neomycin
Nitrates, nitrites
Para-aminosalicylate
Phenytoin (Dilantin)

THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be sent promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

Resume food and any drugs withheld before the
test.

PHOSPHOLIPIDS
Phospholipids consist of one or more fatty acid
molecules and one phosphoric acid radical, and they
usually have a nitrogenous base. The three major
types of body phospholipids are the lecithins, the

132

SECTION I—Laboratory

Tests

cephalins, and the sphingomyelins. In addition to
diet as a source of phospholipids, nearly all body
cells are capable of forming these lipids. Most
endogenous phospholipids are formed, however, in
the liver and intestinal mucosa. The phospholipids
are transported together in circulating blood in the
form of lipoproteins.
Phospholipids are important for the formation of
cell membranes and for the transportation of fatty
acids through the intestinal mucosa into lymph.
Phospholipids also serve as donors of phosphate
groups for intracellular metabolic processes and may
act as carriers in active transport systems. Saturated
lecithins are essential for pulmonary gas exchange,
whereas the cephalins are major constituents of
thromboplastin, which is necessary to initiate the
clotting process. Sphingomyelin is present in large
quantities in the nervous system and acts as an insulator around nerve fibers.24
Phospholipids may be measured as part of an
overall lipid evaluation, but the significance of
altered levels is not completely understood. A direct
relationship between elevated phospholipids and
atherosclerotic cardiovascular disease has not been
demonstrated.
Alterations in phospholipid levels may be seen in
situations similar to those in which serum triglycerides and cholesterol also are abnormal. For example, elevated levels are associated with diabetes
mellitus, nephrotic syndrome, chronic pancreatitis,
obstructive jaundice, and early starvation. Decreased
levels are seen in clients with primary hypolipoproteinemia, severe malnutrition and malabsorption
syndromes, and cirrhosis. Antilipemic drugs (e.g.,
clofibrate) may lower phospholipid levels, and
epinephrine, estrogens, and chlorpromazine tend to
elevate them.
Another clinical application of phospholipid data
is the use of the lecithin:sphingomyelin (L:S) ratio in
estimating fetal lung maturity, with adequate lung
maturity indicated by lecithin levels greater than
those for sphingomyelin by a ratio of 2:1 or greater
(see Chapter 10).
Reference Values
Conventional Units

SI Units

Infants

100–275 mg/dL

1.00–2.75 g/L

Children

180–295 mg/dL

1.80–2.95 g/L

Adults

150–380 mg/dL

1.50–3.80 g/L

Note: Values may vary, depending on the laboratory
performing the test and the age of the client.

INTERFERING FACTORS

Ingestion of alcohol 24 hours before and food
12 hours before the test may falsely elevate
levels.
Ingestion of drugs known to alter phospholipid
levels within 12 hours before the test may alter
results unless the test is being conducted to evaluate such effects.
Antilipemic drugs (e.g., clofibrate) may lower
phospholipid levels.
Epinephrine, estrogens, and chlorpromazine tend
to elevate phospholipid levels.
INDICATIONS FOR SERUM PHOSPHOLIPIDS TEST

Known or suspected disorders that cause or are
associated with altered lipid metabolism:
Altered phospholipid levels are seen in situations similar to those in which serum triglycerides and cholesterol also are altered (see
Tables 5–12 and 5–13).
Elevated levels are associated with diabetes
mellitus, nephrotic syndrome, chronic pancreatitis, obstructive jaundice, and early starvation.
Decreased levels are seen in primary
hypolipoproteinemia, severe malnutrition,
malabsorption syndromes, and cirrhosis.
Support for identifying problems related to fat
metabolism and transport:
Phospholipid formation parallels deposition
of triglycerides in the liver, and severely
decreased levels result in low levels of lipoproteins that are essential for fat transport.
Abnormal bleeding of unknown origin, with
decreased cephalin (a type of phospholipid), a
possible contributor to low levels of thromboplastin
Suspected neurological disorder, which may be
associated with decreased levels of sphingomyelin
(a type of phospholipid)
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
procedure involving collection of a peripheral blood
sample (see Appendix I).
For this test, the client should abstain from alcohol for 24 hours and from food for 12 hours
before the study.
Water is not restricted.
It also is recommended that drugs that may
alter phospholipid levels be withheld for 12
hours before the test, although this practice
should be confirmed with the person ordering
the study.

CHAPTER 5—Blood

THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be sent promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume foods and any drugs withheld before the
test.

LIPOPROTEIN AND CHOLESTEROL
FRACTIONATION
Lipids are transported in the blood as lipoproteins—
complex molecules consisting of triglycerides,
cholesterol, phospholipids, and proteins. Lipoproteins exist in several forms that reflect the different concentrations of their constituents. These
forms, or fractions, are classified according to either
their densities or their electrophoretic mobility.
The lipoprotein fractions in relation to density are
(1) chylomicrons, (2) very-low-density lipoproteins
(VLDL), (3) low-density lipoproteins (LDL), and (4)
high-density lipoproteins (HDL). The least dense
lipoproteins—chylomicrons and VLDL—contain
the highest levels of triglycerides and lower amounts
of cholesterol and protein. LDL and HDL contain

Chemistry

133

the lowest amounts of triglycerides and relatively
higher amounts of cholesterol and protein (see Table
5–10).
Lipoprotein densities correspond to the electrophoretic mobility patterns of the several lipoprotein fractions. The two main fractions of
lipoproteins, as identified by electrophoresis, are
and . -Lipoproteins, which approximate the HDL
(1), migrate with the -globulins. The -lipoproteins, which reflect the VLDL (pre-) and the LDL
(), migrate with the -globulins. Chylomicrons
remain at the origin.
The cholesterol content of the HDL and LDL
fractions also can be determined by measuring total
cholesterol remaining after one fraction has been
removed. Note, however, that HDL cholesterol does
not correlate well with the total cholesterol concentration, is higher in women than in men, and tends
to be inversely proportional to triglyceride levels.
High HDL cholesterol and low LDL cholesterol
levels are predictive of a reduced risk of cardiovascular disease, whereas high LDL cholesterol and low
HDL cholesterol levels are considered risk factors for
atherosclerotic cardiovascular disease. Further, many
health-care providers believe that an adequate lipid
assessment need include only (1) total cholesterol,
(2) HDL cholesterol, (3) serum triglycerides, and (4)
estimate of chylomicron concentration.
Specific conditions associated with altered levels
of lipoprotein fractions are listed in Table 5–14.

Reference Values
Conventional Units

SI Units

Total lipoproteins

400–800 mg/dL

—

Chylomicrons

—

VLDL or pre-

3–32 mg/dL

—

LDL or

38–40 mg/dL

0.98–1.04 mmol/L

HDL or 1

20–48 mg/dL

0.51–1.24 mmol/L

LDL Cholesterol
Age

HDL Cholesterol

Conventional Units

SI Units

Conventional Units

SI Units

25 yr

73–138 mg/dL

1.87–3.53 mmol/L

32–57 mg/dL

0.82–1.46 mmol/L

25–40 yr

90–180 mg/dL

2.30–4.60 mmol/L

32–60 mg/dL

0.82–1.54 mmol/L

40–50 yr

100–185 mg/dL

2.56–4.74 mmol/L

33–60 mg/dL

0.84–1.54 mmol/L

50–65 yr

105–190 mg/dL

2.69–4.96 mmol/L

34–70 mg/dL

0.87–1.79 mmol/L

65 yr

105–200 mg/dL

2.69–5.12 mmol/L

35–75 mg/dL

0.90–1.92 mmol/L

Note: HDL cholesterol values are normally lower in men than in women, with an average range of 22 to 68 mg/dL.

134

SECTION I—Laboratory

TABLE 5–14

•

Lipoprotein
Chylomicrons

Tests

Conditions Associated with Altered Levels of Lipoprotein
Fractions
Increased Level

Decreased Level

Ingested fat

Not applicable—normal value is zero

Ingested alcohol
Types I and V hyperlipoproteinemia
VLDL

Ingested fat

Abetalipoproteinemia

Ingested carbohydrate

Cirrhosis

Ingested alcohol

Hypobetalipoproteinemia

All types of hyperlipoproteinemia
Exogenous estrogens
Diabetes mellitus
Hypothyroidism (primary)
Nephrotic syndrome
Alcoholism
Pancreatitis
Pregnancy
LDL cholesterol

Ingested cholesterol

Types I and V hyperlipoproteinemia

Ingested saturated fatty acids

Hypobetalipoproteinemia

Types II and III hyperlipoproteinemia

Abetalipoproteinemia

Hypothyroidism (primary)

Hyperthyroidism

Biliary obstruction

Cirrhosis

Nephrotic syndrome
HDL cholesterol

Ingested alcohol (moderate amounts)

All types of hyperlipoproteinemia

Chronic hepatitis

Exogenous estrogens

Hypothyroidism (primary)

Hyperthyroidism

Early biliary cirrhosis

Cirrhosis

Biliary obstruction

Tangier disease

INTERFERING FACTORS

Failure to follow usual diet for 2 weeks before the
test may yield results that do not accurately reflect
client status.
Ingestion of alcohol 24 hours before and food 12
hours before the test may alter results.
Excessive exercise 12 hours before the test may
alter results (regular exercise has been found to
lower HDL cholesterol levels).
Numerous drugs may alter results, including
those that are known to alter lipoprotein components (see Tables 5–12 and 5–13).

INDICATIONS FOR LIPOPROTEIN AND
CHOLESTEROL FRACTIONATION

Serum cholesterol levels of greater than 250
mg/dL, which indicate high risk for cardiovascular disease and the need for further evaluation and
possible treatment
Estimation of the degree of risk for cardiovascular
disease:
Individuals with LDL cholesterol levels greater
than 160 mg/dL are considered to be at high
risk.
Individuals at or above the upper reference

CHAPTER 5—Blood

range for HDL cholesterol have half the average
risk, whereas those at or near the bottom have
two, three, or more times the average risk.
Known or suspected disorders associated with
altered lipoprotein levels (see Table 5–14)
Evaluation of response to treatment for altered
levels and support for decisions regarding the
need for drug therapy (LDL cholesterol levels may
decrease with dietary modification alone; if not,
drug treatment is recommended.)
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
procedure involving collection of a peripheral blood
sample (see Appendix I).
For this test, the client should ingest a normal
diet, such that no weight gain or loss will occur for
2 weeks before the study, and should abstain from
alcohol for 24 hours and from food for 12 hours
before the test.
Water is not restricted.
The client also should avoid excessive exercise for
at least 12 hours before the test.
It also is recommended that drugs that may alter
lipoprotein components be withheld for 24 to 48
hours before the test (see Tables 5–12 and 5–13),
although this practice should be confirmed with
the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be sent promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume food and any drugs withheld before the
test, as well as usual activities.
Abnormal values: Note and report increased or
decreased levels indicating atherosclerosis and
high risk for heart disease. Administer ordered
medications. Provide information about a lowfat, low-cholesterol, and low-calorie diet, if
needed.

LIPOPROTEIN PHENOTYPING
Lipoprotein phenotyping is an extension of the
information obtained through lipoprotein fractionation and provides another approach to correlating
laboratory findings with disease.
Six different lipoprotein distribution patterns
(phenotypes) are seen in serums with high levels of

Chemistry

135

cholesterol or triglycerides or both. These phenotypes, which are referred to by their assigned
numbers, have been correlated with genetically
determined abnormalities (familial or primary
hyperlipoproteinemias) and with a variety of
acquired conditions (secondary hyperlipoproteinemias).
Phenotype descriptions have proved useful in
classifying diagnoses and in evaluating treatment
and preventive regimens. Most hyperlipemic serums
can be categorized into lipoprotein phenotypes
without performing electrophoresis if the following
are known: (1) chylomicron status, (2) serum
triglyceride level, (3) total cholesterol, and (4) HDL
cholesterol.
Table 5–15 shows the clinical significance of each
of the lipoprotein phenotypes as primary familial
syndromes and as secondary occurrences caused by
disorders that alter lipid metabolism.
INTERFERING FACTORS

Failure to follow usual diet for 2 weeks before the
test may yield results that do not accurately reflect
client status.
Ingestion of alcohol 24 hours before and food 12
hours before the test may alter results.
Excessive exercise 12 hours before the test may
alter results.
Numerous drugs, including those that are known
to alter lipoprotein components (see Tables 5–12,
5–13, and 5–15) may alter results.
INDICATIONS FOR LIPOPROTEIN PHENOTYPING

Further evaluation of elevated serum cholesterol
levels and results of lipoprotein and cholesterol
fractionation
Family history of primary hyperlipoproteinemia
(hyperlipidemia)
Identification of the client’s specific lipoprotein
phenotype
Known or suspected disorders associated with the
several lipoprotein phenotypes (see Table 5–15)
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
study involving collection of a peripheral blood
sample (see Appendix I).
For this test, the client should ingest a normal
diet, so that no weight gain or loss will occur for 2
weeks before the study, and should abstain from
alcohol for 24 hours and from food for 12 hours
before the test.
Water is not restricted.
The client also should avoid excessive exercise for
at least 12 hours before the test.

136

SECTION I—Laboratory

TABLE 5–15
Phenotype
I

•

Tests

Clinicopathological Significance of Lipoprotein Phenotypes
May Occur
Secondary to

Familial Syndrome
Abdominal pain

Insulin-dependent diabetes

Eruptive xanthomas

Lupus erythematosus

Lipemia retinalis

Dysglobulinemias

Early vascular disease absent

Pancreatitis

Early, severe vascular disease

High-cholesterol diet

Prominent xanthomas

Nephrotic syndrome
Porphyria

Remarks
Lipoprotein lipase is
deficient.

Familial trait is autosomal
dominant; homozygotes
are especially severely
affected.

Hypothyroidism
Dysglobulinemias
Obstructive liver diseases
III

Accelerated vascular disease,
onset in adulthood

Hypothyroidism

Xanthomas, palmar yellowing

Dysglobulinemias

Abnormal glucose tolerance

Uncontrolled diabetes

Diet, lipid-lowering drugs
are very effective.

Hyperuricemia
IV

Accelerated vascular disease,
onset in adulthood

Obesity

Weight loss lowers VLDL.

Abnormal glucose tolerance

High alcohol intake

High-fat diet may convert
to type V.

Hyperuricemia

Oral contraceptives
Diabetes
Nephrotic syndrome
Glycogen storage disease

Abdominal pain

High alcohol intake

Pancreatitis

Diabetes

Eruptive xanthomas

Nephrotic syndrome

Abnormal glucose tolerance

Pancreatitis

Vascular disease not associated

Hypercalcemia

Weight loss does not
lower VLDL.

From Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 11. FA Davis,
Philadelphia, 2000, p. 477, with permission.

It also is recommended that drugs that may alter
lipoprotein components be withheld for 24 to
48 hours or longer before the test (see Tables
5–12, 5–13, and 5–15), although this practice
should be confirmed with the person ordering the
study.
THE PROCEDURE

A venipuncture is performed and the sample

collected in either a red- or lavender-topped tube,
depending on the laboratory’s procedure for determining lipoprotein phenotypes. The sample should
be sent to the laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

CHAPTER 5—Blood

Chemistry

137

Reference Values
Phenotype
I

IIa

IIb

III

Frequency

Very
rare

Common

Uncommon

Very
common

Rare

Chylomicrons

↑↑↑

Normal

Normal or ↑

Normal

↑↑

Pre--lipoproteins
(approximates
VLDL)

↑

↑↑

↑

(these two
bands merge)

↑↑↑

↑↑

-Lipoproteins
(approximates
LDL)

↓

↑↑

Normal
or ↑

Normal
or ↓

1-Lipoproteins
(approximates
HDL)

↓

Normal

Normal
or ↓

Total cholesterol

Normal
or ↑

↑↑

Normal
or ↑

↑↑

Total triglycerides

↑↑↑

Normal

↑

↑↑ or ↑↑↑

↑↑↑

Refrigerated serum
or plasma

“Cream”/
clear or
turbid

Clear

or
turbid

turbid

“Cream”/
turbid

From Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, p 476, with permission.

Resume food and any drugs withheld before the
test, as well as usual activities.

BILIRUBIN
Bilirubin is a degradation product of the pigmented
heme portion of hemoglobin. Old, damaged, and
abnormal erythrocytes are removed from the circulation by the spleen and to some extent by the liver
and bone marrow. The heme component of the red
blood cells is oxidized to bilirubin by the reticuloendothelial cells and released into the blood.
In the blood, the fat-soluble bilirubin binds to
albumin as unconjugated (prehepatic) bilirubin for
transport to the liver. In the liver, hepatocytes detach
bilirubin from albumin and conjugate it with
glucuronic acid, which renders the bilirubin water
soluble. Most of the conjugated (posthepatic) bilirubin is excreted into the hepatic ducts and then into
bile. Only small amounts of conjugated bilirubin
diffuse from the liver back into the blood. Thus,
most circulating bilirubin is normally in the unconjugated form.

Bilirubin is an excretory product that serves no
physiological function in bile or blood. Once the
conjugated bilirubin in bile enters the intestine,
most is converted to a series of urobilinogen
compounds and excreted into the stool as stercobilinogen after oxidation. A lesser amount is recycled
to the liver and either returned to bile or excreted in
urine as urobilinogen, which is oxidized to urobilin.
Bilirubin and its degradation products are
pigments and provide the yellow tinge in normal
serum, the yellow-green hue in bile, the brown in
stools, and the yellow in urine. Abnormally elevated
serum bilirubin levels produce jaundice; obstruction
to biliary excretion of bilirubin may produce lightcolored stools and dark urine.
The terms indirect and direct, which are used to
describe unconjugated (prehepatic) and conjugated
(posthepatic) bilirubin, respectively, derive from the
methods of testing for their presence in serum.
Conjugated bilirubin is described as direct (direct
reacting) because it is water soluble and can be
measured without modification. Unconjugated
bilirubin must be rendered soluble with alcohol or

138

SECTION I—Laboratory

TABLE 5–16

•

Tests

Causes of Elevations in Indirect and Direct Bilirubin Levels

Increased Indirect (Unconjugated) Bilirubin

Increased Direct (Conjugated) Bilirubin

Hemolysis: hemoglobinopathies, spherocytosis,
G-6-PD deficiency, autoimmunity, transfusion
reaction

Intrahepatic disruption: viral hepatitis, alcoholic
hepatitis, chlorpromazine, cirrhosis

Red blood cell degradation: hemorrhage into soft
tissues or body cavities, inefficient erythropoiesis, pernicious anemia

Extrahepatic bile duct obstruction: gallstones;
carcinoma of gallbladder, bile ducts, or head of
pancreas; bile duct stricture from inflammation
or surgical misadventure

Bile duct disease: biliary cirrhosis, cholangitis (idiopathic, infectious), biliary atresiaa

Defective hepatocellular uptake or conjugation:
viral hepatitis, hereditary enzyme deficiencies
(Gilbert, Crigler-Najjar syndromes), hepatic
immaturity in newborns

other solvents before the test can be performed and
is thus referred to as indirect (indirect reacting).
Impaired liver function causes dramatic increases
in serum bilirubin levels (hyperbilirubinemia).
Bilirubin must be in the conjugated form for normal
excretion via bile, stools, and urine. When the liver is
unable to conjugate bilirubin adequately, serum
levels of unconjugated bilirubin rise. Disorders in
which excessive hemolysis of red blood cells is
combined with impaired liver function also produce
hyperbilirubinemia. An example is physiological
jaundice of the newborn, in which the increased
destruction of red blood cells, common after birth, is
combined with the immature liver’s inability to
conjugate sufficient bilirubin. Kernicterus, a complication of newborn hyperbilirubinemia, occurs when
unconjugated bilirubin is deposited in brain tissue.
Impaired excretion of conjugated (posthepatic,
direct) bilirubin from the liver into the bile ducts or
from the biliary tract itself causes this form of bilirubin to be reabsorbed from the liver into the blood,

with resultant elevated serum levels. Because conjugated bilirubin is water soluble and readily crosses
the renal glomerulus, excessive amounts may be
excreted in the urine. The stools, however, are lighter
in color because of diminished amounts of conjugated bilirubin in the gut.
Serum bilirubin levels are measured as total
bilirubin, indirect bilirubin, and direct bilirubin.
Total bilirubin reflects the combination of unconjugated and conjugated bilirubin in the serum and can
be used to screen clients for possible disorders
involving bilirubin production and excretion. If total
bilirubin is normal, the levels of indirect (unconjugated) and direct (conjugated) bilirubin also are
assumed to be normal in most cases.
When total bilirubin levels are elevated, indirect
and direct bilirubin levels are measured to determine the source of the overall elevation. Specific
causes of elevations in indirect and direct bilirubin
are shown in Table 5–16. Numerous drugs also may
alter bilirubin levels.

Reference Values
Conventional Units

SI Units

Total bilirubin
Newborns

2.0–6.0 mg/dL

34.0–102.0 mol/L

48 hr

6.0–7.0 mg/dL

102.0–120.0 mol/L

5 day

4.0–12.0 mg/dL

68.0–205.0 mol/L

1 mo–adults

0.3–1.2 mg/dL

5.0–20.0 mol/L

Indirect bilirubin (unconjugated, prehepatic)
1 mo–adults

0.3–1.1 mg/dL

5.0–19.0 mol/L

0.1–0.4 mg/dL

1.7–6.8 mol/L

Direct bilirubin
1 mo–adults

CHAPTER 5—Blood

INTERFERING FACTORS

Prolonged exposure of the client, as well as of the
blood sample, to sunlight and ultraviolet light
reduces serum bilirubin levels.
Failure of the client to follow dietary restrictions
before the test.
Fasting normally lowers indirect bilirubin levels.
In Gilbert’s syndrome, a congenital defect in
bilirubin degradation, chronically elevated levels
of indirect bilirubin increase dramatically in the
fasting state.
Numerous drugs may elevate bilirubin levels (e.g.,
steroids, sulfonamides, sulfonylureas, barbiturates, antineoplastic agents, propylthiouracil,
allopurinol, antibiotics, gallbladder dyes, caffeine,
theophylline, indomethacin, and any drugs that
are considered hepatotoxic); it is recommended
that such drugs be withheld for 24 hours before
the test, if possible.
INDICATIONS FOR BILIRUBIN TEST

Known or suspected hemolytic disorders, including transfusion reactions, as indicated by elevated
total and indirect bilirubin levels (see also Table
5–16):
Hemolysis alone rarely causes indirect bilirubin
levels higher than 4 or 5 mg/dL.
If hemolysis is combined with impaired or
immature liver function, levels may rise more
dramatically.
Confirmation of observed jaundice:
Jaundice manifests when serum levels of indirect or direct bilirubin reach 2 to 4 mg/dL.
Determination of the cause of jaundice (e.g., liver
dysfunction, hepatitis, biliary obstruction, carcinoma)
Support for diagnosing liver dysfunction as
evidenced by elevated direct and total bilirubin
levels or by elevation of all three levels if bile duct
drainage also is impaired
Support for diagnosing biliary tract obstruction
as evidenced by elevated direct and total bilirubin
levels or by elevation of all three levels if liver
function is impaired25
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
study involving collection of a peripheral blood
sample (see Appendix I).
For these tests, the client should fast from foods
for at least 4 hours before the test.
Water is not restricted.
Because many drugs may alter bilirubin levels (see
section titled “Interfering Factors”), a medication
history should be obtained.

Chemistry

139

It is recommended that those drugs that may alter
test results be withheld for 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample
obtained in a red-topped tube. The sample should
be handled gently to avoid hemolysis and sent
immediately to the laboratory. The sample should
not be exposed for prolonged periods to sunlight
(i.e., more than 1 hour), ultraviolet light, or fluorescent lights. In infants, a capillary sample is obtained
by heelstick.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume food and any drugs withheld before the
test.
Abnormal values: Note and report increased
levels. Assess for associated signs and symptoms
of hyperbilirubinemia such as jaundice, pruritus,
pain caused by liver disease, biliary obstruction,
or food intolerances. Administer phenobarbital if
levels are greater than 12 mg/dL in newborns,
because this can lead to central nervous system
damage. Prepare for exchange transfusion if level
is greater than 15 mg/dL.

ENZYMES
Enzymes are catalysts that enhance reactions without directly participating in them. Individual
enzymes, each of which has its own substrate and
product specificity, exist for nearly all of the metabolic reactions that maintain body functions.
Enzymes are normally intracellular molecules.
Because certain metabolic reactions occur in many
tissues, the involved enzymes exist in many cell
types. Enzymes with more restricted metabolic
functions are found in only one of several specialized cell types. The presence of enzymes in circulating blood indicates cellular changes that have
permitted their escape into extracellular fluid. The
continuous synthesis and destruction of the cells of
the enzymes’ origins, for example, allow small
amounts of enzymes to appear in the blood. Cellular
disruption caused by damage by disease, toxins, or
trauma, as well as increased cell wall permeability,
also elevates serum enzyme levels. Additional causes
of elevated enzyme levels are an increase in the
number or activity of enzyme-containing cells and
decreases in normal excretory or degradation mechanisms.

140

SECTION I—Laboratory

Tests

Decreased serum enzyme levels rarely have diagnostic significance because so few enzymes are present in substantial quantity. Enzyme levels may
decline if the number of synthesizing cells declines,
if generalized or specific restriction in protein
synthesis occurs (enzymes are proteins), or if excretion or degradation increases.
Very few enzymes are studied routinely. Although
highly specialized enzyme analysis is applied to the
study of many genetically determined diseases, most
diagnostic enzyme studies involve only those
enzymes with changing values in serum, providing
inferential or confirmatory evidence of various
pathological processes. A major goal of enzyme
analysis is to localize disease processes to specific
organs, preferably to specific functional subdivisions
or even to specific cellular activities. Enzymes
unique to a single cell type or found in only a few
sites are particularly useful in this regard. The source
of elevations of those enzymes with widespread
distribution also can be determined by partitioning
total activity into isoenzyme fractions. Isoenzymes
are different forms of a single enzyme with
immunologic, physical, or chemical characteristics
distinctive for their tissue of origin.
Efforts to standardize the study of enzymes (enzymology) have led to new terminology for naming
and measuring enzymes. The Commission on
Enzymes of the International Union of Biochemistry
(IUB) has classified enzymes according to their
biochemical functions, assigning to each a numerical designation that embodies class, subclass, and
specification number. The IUB has also assigned
descriptive names according to the specific reaction
catalyzed and, in many cases, a practical name useful
for common reference. One result of this standardization is that enzymes that have been studied for
years have been renamed according to the new
terminology. For example, the liver enzyme that was
formerly called glutamic-oxaloacetic transaminase
(GOT) is now named aspartate aminotransferase
(AST).
Another attempt to standardize enzymology is the
introduction of international units (IU) for reporting enzyme activity. One IU of an enzyme is the
amount that catalyzes transformation of 1 mol of
substrate per minute under defined conditions. The
actual amounts vary among enzymes, and the IU is
not a single universally applicable value that can be
used to compare enzymes of different characteristics.26
In this section, enzymes associated with organs
and tissues such as the liver, pancreas, bone, heart,
and muscle are discussed. Enzymes specific to red
and white blood cells are included in Chapter 1.

Alanine Aminotransferase
Alanine aminotransferase (ALT), formerly known as
glutamic-pyruvic transaminase (GPT), catalyzes the
reversible transfer of an amino group between the
amino acid, alanine, and -ketoglutamic acid.
Hepatocytes are virtually the only cells with high
ALT concentrations, although the heart, kidneys,
and skeletal muscles contain moderate amounts.
Elevated serum ALT levels are considered a sensitive index of liver damage resulting from a variety of
disorders and numerous drugs, including alcohol.
Elevations also may be seen in nonhepatic disorders
such as muscular dystrophy, extensive muscular
trauma, myocardial infarction, congestive heart
failure (CHF), and renal failure, although the
increase in ALT produced by these disorders is not as
great as that produced by conditions affecting the
liver.
This test was formerly known as the serum
glutamic-pyruvic transaminase (SGPT) test.
Reference Values
Conventional Units

SI Units

10–30 U/L

0.17–0.51 kat/L

1–36 U/L

0.02–0.61 kat/L

5–35 U/L

0.08–0.60 kat/L

5–25 U/L

0.08–0.43 kat/L

8–50 U/L

0.14–0.85 kat/L

4–36 U/L

0.07–0.61 kat/L

Note: Reference values vary among laboratories and according to the method used for reporting results.

INTERFERING FACTORS

Numerous drugs, including alcohol, may falsely
elevate levels.
INDICATIONS FOR ALANINE AMINOTRANSFERASE
TEST

Known liver disease or liver damage caused by
hepatotoxic drugs:
Markedly elevated levels (sometimes as high as
20 times normal) are considered confirmatory
of liver disease.
A sudden drop in serum ALT levels in the presence of acute illness after extreme elevation of
blood levels (e.g., as seen in severe viral or toxic
hepatitis) is an ominous sign and indicates that
so many cells have been damaged that no additional source of enzyme remains.

CHAPTER 5—Blood

Monitoring for response to treatment for liver
disease, with tissue repair indicated by gradually
declining levels
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
study involving collection of a peripheral blood
sample (see Appendix I).
For this test, the client should abstain from alcohol for at least 24 hours before the study.
Because many drugs may alter ALT levels, a
medication history should be obtained. It is
recommended that drugs that may alter test
results be withheld for 12 hours before the test,
although this practice should be confirmed with
the person ordering the study.

Chemistry

141

hours, and lactic dehydrogenase, which begins rising
12 hours or more after infarction and remains
elevated for a week or more. Elevation of AST
cannot be used as the single enzyme indicator for
myocardial infarction, because it also rises in several
other conditions included in the differential diagnosis of heart attack. Other disorders associated with
elevated AST, and the magnitude of those elevations,
are listed in Table 5–17. Note also that numerous
drugs, especially those known to be hepatotoxic or
nephrotoxic, may elevate AST levels.27
The test for AST was formerly known as serum
glutamic-oxaloacetic transaminase (SGOT).
INTERFERING FACTORS

Numerous drugs may falsely elevate levels.

THE PROCEDURE

A venipuncture is performed and the sample is
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.

TABLE 5–17 • Conditions Affecting
Serum Aspartate Aminotransferase
Levels

NURSING CARE AFTER THE PROCEDURE

Pronounced Elevation (5 or more times normal)

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any drugs withheld before the test.
Abnormal levels: Note and report increased
levels. Assess symptoms of liver dysfunction associated with increases such as jaundice, anorexia,
and fatigue. Relate increases to other liver function tests. Provide rest and interventions to
conserve energy. Tell client which drugs to avoid
and encourage client to eat a healthy diet.

Aspartate Aminotransferase
Aspartate aminotransferase (AST), formerly known
as glutamic-oxaloacetic transaminase (GOT),
catalyzes the reversible transfer of an amino between
the amino acid, aspartate, and -ketoglutamic acid.
ALT exists in large amounts in both liver and
myocardial cells and in smaller but significant
amounts in skeletal muscles, kidneys, pancreas, and
brain.
Serum AST rises when cellular damage occurs to
the tissues in which the enzyme is found. When
heart muscle suffers ischemic damage, serum AST
rises within 6 to 8 hours; peak values occur at 24 to
48 hours and decline to normal within 72 to 96
hours. Elevation of AST occurs midway in the time
sequence between that of creatine phosphokinase
(CPK), which rises very early and falls within 48

Acute hepatocellular damage
Myocardial infarction
Shock
Acute pancreatitis
Infectious mononucleosis
Moderate Elevation (3–5 times normal)
Biliary tract obstruction
Cardiac arrhythmias
Congestive heart failure
Liver tumors
Chronic hepatitis
Muscular dystrophy
Dermatomyositis
Slight Elevation (up to 3 times normal)
Pericarditis
Cirrhosis, fatty liver
Pulmonary infarction
Delirium tremens
Cerebrovascular accident
Hemolytic anemia
Adapted from Sacher, RA, and McPherson, RA:
Widmann’s Clinical Interpretation of Laboratory
Tests, ed 11. FA Davis, Philadelphia, 2000, p. 415,
with permission.

142

SECTION I—Laboratory

Tests

Reference Values
Conventional Units

SI Units

Newborns

16–72 U/L

0.27–1.22 kat/L

6 mo

20–43 U/L

0.34–0.73 kat/L

1 yr

16–35 U/L

0.27–0.60 kat/L

5 yr

19–28 U/L

0.32–0.48 kat/L

Men

8–46 U/L

0.14–0.78 kat/L

Women

7–34 U/L

0.12–0.58 kat/L

Adults

INDICATIONS FOR ASPARTATE AMINOTRANSFERASE
TEST

Suspected disorders or injuries involving the liver,
myocardium, kidneys, pancreas, or brain, with
elevated levels indicating cellular damage to
tissues in which AST is normally found (see Table
5–17):
In myocardial infarction, AST rises within 6 to
8 hours, peaks at 24 to 48 hours, and declines to
normal within 72 to 96 hours.
Monitoring of response to therapy with potentially hepatotoxic or nephrotoxic drugs
Monitoring of response to treatment for various
disorders in which AST may be elevated, with
tissue repair indicated by declining levels
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
study involving collection of a peripheral blood
sample (see Appendix I).
Because many drugs alter AST levels, a medication
history should be obtained. It is recommended
that any drugs that may alter test results be withheld for 12 hours before the test, although this
practice should be confirmed with the person
ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample is
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any drugs withheld before the test, pending test results.

Complications and precautions: Increases in this
enzyme level in relation to ALT and other assessment data may indicate a cardiac disorder.
Monitor vital signs and cardiac activity by electrocardiogram (ECG).

Alkaline Phosphatase
Phosphatases are enzymes that cleave phosphate
from compounds with a single phosphate group.
Those that are optimally active at pH 9 are grouped
under the name alkaline phosphatase (ALP).
ALP is elaborated by a number of tissues. Liver,
bone, and intestine are the major isoenzyme sources.
During pregnancy, the placenta also is an abundant
source of ALP, and certain cancers elaborate small
amounts of a distinctive form of ALP called the
Regan enzyme. Additional sources of ALP are the
proximal tubules of the kidneys, the lactating
mammary glands, and the granulocytes of circulating blood (see Chapter 1 section titled “Leukocyte
Alkaline Phosphatase”).
Bone ALP predominates in normal serum, along
with a modest amount of hepatic isoenzyme, which
is believed to derive largely from the epithelium of
the intrahepatic biliary ducts rather than from the
hepatocytes themselves. Levels of intestinal ALP
vary; most people have relatively little, but isolated
elevations of this enzyme have been observed.
Intestinal ALP enters the blood very briefly while fats
are being digested and absorbed, but intestinal
disease rarely affects serum ALP levels.
Conditions associated with elevated serum ALP
levels, and the magnitude of those elevations, are
listed in Table 5–18.28 Numerous drugs also may
elevate serum ALP levels.
Decreased levels are seen in cretinism, secondary
growth retardation, scurvy, achondroplasia, and,
rarely, hypophosphatasia.

CHAPTER 5—Blood

Chemistry

143

Reference Values
General Reference
Levels

Bessey-Lowry
Method

Bodansky
Method

King-Armstrong
Method

Newborns

50–65 U/L

—

Children

20–150 U/L

3.4–9.0 U/L

5–14 U/L

15–30 U/L

Adults

20–90 U/L

0.8–2.3 U/L

1.5–4.5 U/L

4–13 U/L

INTERFERING FACTORS

Numerous drugs, including IV albumin, may
falsely elevate levels.

•

Conditions Associated
with Elevated Serum Alkaline
Phosphatase Levels

TABLE 5–18

Pronounced Elevation (5 or more times normal)
Advanced pregnancy
Biliary obstruction
Biliary atresia
Cirrhosis
Osteitis deformans
Osteogenic sarcoma
Hyperparathyroidism (primary, or secondary to
chronic renal disease)
Paget’s disease

Clofibrate, azathioprine (Imuran), and fluorides
may falsely decrease levels.
INDICATIONS FOR SERUM ALKALINE
PHOSPHATASE TEST

Signs and symptoms of disorders associated with
elevated ALP levels (e.g., biliary obstruction,
hepatobiliary disease, bone disease including
malignant processes) (see also Table 5–18)
Differentiation of obstructive biliary disorders
from hepatocellular disease, with greater elevations of ALP seen in obstructive biliary disorders
Known renal disease to determine effects on bone
metabolism
Signs of growth retardation in children
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter ALP levels, a
medication history should be obtained.

Infusion of albumin of placental origin

THE PROCEDURE

Moderate Elevation (3–5 times normal)

Infectious mononucleosis

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.

Metastatic tumors in bone

NURSING CARE AFTER THE PROCEDURE

Granulomatous or infiltrative liver diseases

Metabolic bone diseases (rickets, osteomalacia)
Extrahepatic duct obstruction
Mild Elevation (up to 3 times normal)
Viral hepatitis
Chronic active hepatitis
Cirrhosis (alcoholic)
Healing fractures
Early pregnancy
Growing children
Large doses of vitamin D
Congestive heart failure

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Abnormal levels: Note and report increased
levels. Correlate with serum calcium and phosphorus, serum bilirubin, and isoenzymes to determine reason for treatments, progress, and
prognosis in diseases of the bone or liver. Assess
for jaundice and pathological fracture. If client is
pregnant, handle extremities carefully and protect
from trauma. Administer ordered vitamin D.
Provide comfort measures (soothing bath for
pruritus, pain control, support for body image
changes) to treat jaundice, if it is present. Advise
client to restrict dietary fat.

144

SECTION I—Laboratory

Tests

Alkaline Phosphatase Isoenzymes

THE PROCEDURE

If serum alkaline phosphatase (ALP) levels are
elevated but the clinical picture does not provide
enough information to determine the origin of the
excess, ALP isoenzymes are evaluated. The major
ALP isoenzymes derive from liver, bone, intestine,
and placenta.
ALP isoenzymes may be partitioned by electrophoresis or by exploitation of differences in physical properties on optimal substrates. Electrophoresis has been applied with only modest success.
Hepatic and intestinal isoenzymes are easier to
differentiate with this method than are hepatic and
bone enzymes. Because hepatic ALP is more heat
resistant than bone ALP, the most common way to
differentiate between these two isoenzymes is by
heating the serum to 132.8 F (56 C).
Evaluation of ALP isoenzymes usually focuses on
measuring those of hepatic origin not affected by
bone growth or pregnancy. These are 5′-nucleotidase, leucine aminopeptidase, and -glutamyl
transpeptidase.

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

LEUCINE AMINOPEPTIDASE
Leucine aminopeptidase (LAP), an isoenzyme of
alkaline phosphatase, is widely distributed in body
tissues, with greatest concentrations found in hepatobiliary tissues, pancreas, and small intestine.
Elevated levels are associated with biliary obstruction resulting from gallstones and tumors, including
those of the head of the pancreas, strictures, and
atresia. Advanced pregnancy and therapy with drugs
containing estrogen and progesterone also may raise
LAP levels.

5′-NUCLEOTIDASE

Reference Values

5′-Nucleotidase (5′-N), an isoenzyme of ALP, is a
specific phosphomonoesterase formed in the hepatobiliary tissues. Elevated serum 5′-N levels are associated with biliary cirrhosis, carcinoma of the liver
and biliary structures, and choledocholithiasis or
other biliary obstruction.

Leucine Conventional Units

SI Units

Men

0.80–2.00 mg/dL

61.0–152.0 mol/L

Women

0.75–1.85 mg/dL

57.0–141.0 mol/L

Note: Values may vary depending on the units of measure
used by the laboratory performing the test.

Reference Values
Conventional Units
0–1.6 U

SI Units
27–233 nmol/s/L

0.3–3.2 U (Bodansky)

INDICATIONS FOR 5′-NUCLEOTIDASE TEST

Elevated alkaline phosphatase of uncertain etiology:
Elevated 5′-N levels support the diagnosis of
hepatobiliary disorders as the source of the
elevated alkaline phosphatase.
Normal levels support the diagnosis of bone
disease as the source of the elevated alkaline
phosphatase.
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving collection of a peripheral blood sample
(see Appendix I).

INTERFERING FACTORS

Advanced pregnancy and therapy with drugs
containing estrogen and progesterone may falsely
elevate levels.
INDICATIONS FOR LEUCINE AMINOPEPTIDASE
TEST

Elevated ALP of uncertain etiology:
Elevated levels support the diagnosis of hepatobiliary or pancreatic disease or both as the
source of the elevated ALP.
Normal levels support the diagnosis of bone
disease as the source of the elevated ALP.
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of a peripheral blood sample
(see Appendix I).
Some laboratories require the client to fast from
food for 8 hours before the test.

CHAPTER 5—Blood

THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any food withheld before the test.

-GLUTAMYL TRANSPEPTIDASE
-Glutamyl transpeptidase (GGT), an isoenzyme of
ALP, catalyzes the transfer of glutamyl groups
among peptides and amino acids. Hepatobiliary
tissues and renal tubular and pancreatic epithelia
contain large amounts of GGT. Other sources
include the prostate gland, brain, and heart.
Most GGT in serum derives from hepatobiliary
sources, and elevated levels point to hepatobiliary
disease.
INTERFERING FACTORS

Alcohol, barbiturates, and phenytoin may elevate
GGT levels.
Late pregnancy and oral contraceptives may
produce lower than normal values.
INDICATIONS FOR -GLUTAMYL TRANSPEPTIDASE
TEST

Elevated alkaline phosphatase of uncertain etiology:
Pronounced elevations are seen in clients with
obstructive disorders of the hepatobiliary tract
and hepatocellular carcinoma.

145

Modest elevations occur with hepatocellular
degeneration (e.g., cirrhosis) and with pancreatic or renal cell damage or neoplasms.
Other disorders associated with elevated GGT
levels include CHF, acute myocardial infarction
(after 4 to 10 days), hyperlipoproteinemia (type
IV), diabetes mellitus with hypertension, and
epilepsy.
Normal levels in the presence of elevated ALP
support the diagnosis of bone disease.
Known or suspected alcohol abuse, including
monitoring of individuals participating in alcohol
abstinence programs
About 60 to 80 percent of individuals considered to have alcohol abuse problems have
elevated GGT levels, whether or not other signs
of liver damage are present.
Moderate increases in GGT levels occur with
low alcohol intake.
A significant sustained rise occurs with ingestion of six or more drinks per day.
Normal levels return within 2 to 6 weeks of
abstinence from alcohol.
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any test involving collection of a peripheral blood
sample (see Appendix I).
Some laboratories require the client to fast from
food for 8 hours before the test.
When the test is conducted to determine whether
the liver is the source of elevated ALP, the client
should abstain from alcohol for 2 to 3 weeks
before the test. This restriction may not apply
when the test is used to monitor compliance with
alcohol abstinence programs.
The client’s reported intake (or nonintake) of
alcohol should, however, be noted.

Reference Values
Conventional Units
Newborns

Chemistry

SI Units

5 times children’s (1–2 yr) values

Children
1–2 yr

3–30 U/L

0.05–0.51 kat/L

5–15 yr

5–27 U/L

0.08–0.46 kat/L

Men

6–37 U/L

0.10–0.63 kat/L

Women 45 yr

5–27 U/L

0.08–0.46 kat/L

Women 45 yr

6–37 U/L

0.10–0.63 kat/L

Adults

146

SECTION I—Laboratory

Tests

THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any food withheld before the test.

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any drugs withheld before the test, pending test results.

Isocitrate Dehydrogenase
Isocitrate dehydrogenase (ICD) catalyzes the decarboxylation of isocitrate in the Krebs cycle. This
enzyme is important in controlling the rate of the
cycle, which must be precisely adjusted to meet the
energy needs of cells. ICD is found in the liver, heart,
skeletal muscle, placenta, platelets, and erythrocytes.
Reference Values
Conventional Units

SI Units

Newborns

4.0–28.0 U/L

0.06–0.48 kat/L

Adults

1.27–7.0 U/L

0.02–0.12 kat/L

Ornithine Carbamoyltransferase
Ornithine carbamoyltransferase (OCT), formerly
known as ornithine transcarbamoylase, catalyzes
ornithine to citrulline in the urea cycle before its link
with the citric acid cycle. Its importance stems from
its role in the conversion of ammonia to urea by the
liver. Decreased levels may be seen in inherited
disorders associated with a partial block in the urea
cycle.
Reference Values
Conventional Units

SI Units

8–20 mIU/mL
INTERFERING FACTORS

Numerous drugs, including those that are hepatotoxic, may cause elevated levels.
INDICATIONS FOR ISOCITRATE DEHYDROGENASE
TEST

Elevated serum aspartate aminotransferase (ALT,
SGOT) or ALP of uncertain etiology, or both:
Elevated ICD levels are seen in early viral hepatitis, cancer of the liver, intrahepatic and extrahepatic obstruction, biliary atresia, cirrhosis,
and preeclampsia.
Therapy with potentially hepatotoxic drugs that
may lead to elevated ICD levels early in the course
of treatment
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter ICD levels, a
medication history should be obtained. It is
recommended that any drugs that may alter test
results be withheld for 24 hours before the test,
although this practice should be confirmed with
the person ordering the study.

8–20 U/L

0.02–0.34 kat/L

INTERFERING FACTORS

Hepatotoxic drugs and chemicals may produce
elevated levels.
INDICATIONS FOR ORNITHINE
CARBAMOYLTRANSFERASE TEST

Elevated serum ALP of uncertain etiology:
Elevated OCT levels are seen in viral hepatitis,
cholecystitis, cirrhosis, cancer of the liver, and
obstructive jaundice.
Therapy with hepatotoxic drugs or exposure to
hepatotoxic chemicals, with early effects indicated
by elevated OCT levels
Suspected mushroom poisoning as indicated by
elevated levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter OCT levels, a
medication history should be obtained. It is
recommended that any drugs that may alter test

CHAPTER 5—Blood

results be withheld for 24 hours before the test,
although this practice should be confirmed with
the person ordering the study.

Chemistry

147

• Causes of Elevated
Serum Amylase

TABLE 5–19

THE PROCEDURE

Pronounced Elevation (5 or more times normal)

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.

Acute pancreatitis
Pancreatic pseudocyst
Morphine administration
Moderate Elevation (3–5 times normal)

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any drugs withheld before the test, pending test results.

Advanced carcinoma of the pancreatic head
Mumps
Parotitis
Perforated peptic ulcer (sometimes)
Duodenal obstruction
Mild Elevation (up to 3 times normal)

Serum Amylase
Amylase is a digestive enzyme that splits starch into
disaccharides such as maltose. Although many cells
have amylase activity (e.g., liver, small intestine,
skeletal muscle, fallopian tubes), amylase circulating
in normal serum derives from the parotid glands
and the pancreas. Unlike many other enzymes,
amylase activity is primarily extracellular; it is
secreted into saliva and the duodenum, where it
splits large carbohydrate molecules into smaller
units for further digestive action by intestinal
enzymes.
Elevations in serum amylase are generally seen in
pancreatic inflammations, which cause disruption of
pancreatic cells and absorption of the extracellular
enzyme from the intestine and peritoneal lymphatics. Serum amylase levels also rise sharply after
administration of drugs that constrict pancreatic
duct sphincters. The most common offender is
morphine, and this drug is never indicated for individuals with abdominal pain that could be of
pancreatic or biliary tract origin. Other drugs that
may produce elevated serum amylase levels are
codeine, chlorothiazides, aspirin, pentazocine, corticosteroids, oral contraceptives, pancreozymin, and
secretin. Specific causes of elevated serum amylase,

Chronic pancreatitis (nonadvanced)
Renal failure
Common bile duct obstruction
Gastric resection
Adapted from Sacher, RA, and McPherson, RA:
Widmann’s Clinical Interpretation of Laboratory
Tests, ed 11. FA Davis, Philadelphia, 2000, p. 554,
with permission.

and the magnitude of the elevations produced, are
listed in Table 5–19.
INTERFERING FACTORS

A number of drugs may produce elevated levels
(e.g., morphine, codeine, chlorothiazides, aspirin,
pentazocine, corticosteroids, oral contraceptives,
pancreozymin, and secretin).
High blood glucose levels, which may be a result
of diabetes mellitus or IV glucose solutions, can
lead to decreased levels.
INDICATIONS FOR SERUM AMYLASE TEST

Diagnosis of early acute pancreatitis:
Serum amylase begins rising within 6 to 24

Reference Values
Conventional Units

SI Units

Children

60–160 U/dL

1.88–5.03 kat/L

Adults

80–180 U/dL (Somogyi)

1.36–3.0 kat/L

45–200 U/dL (dye)
Note: Values may vary according to the laboratory performing the test.

148

SECTION I—Laboratory

Tests

hours after onset and returns to normal in 2 to
7 days.
Urine amylase levels may remain elevated for
several days after serum amylase levels return
to normal.
Detection of blunt trauma or inadvertent surgical
trauma to the pancreas as indicated by elevated
levels
Diagnosis of macroamylasemia, a disorder seen in
alcoholism, malabsorption syndrome, and other
digestive problems with circulating complexes of
amylase and high-molecular-weight dextran
(findings include high serum amylase and negative urine amylase)
Support for diagnosing other disorders associated
with elevated serum amylase levels (see Table
5–19)
Support for diagnosing disorders associated with
decreased amylase levels, such as advanced
chronic pancreatitis, advanced cystic fibrosis, liver
disease, liver abscess, toxemia of pregnancy, severe
burns, and cholecystitis

fluids, nasogastric tube (NG) insertion, and bowel
decompression to decrease pancreatic stimulation. Instruct client to avoid alcohol intake and to
reduce carbohydrate intake if absorption problem
exists.

Serum Lipase
Lipases split triglycerides into fatty acids and glycerol. Different lipolytic enzymes have different
specific substrates, but overall activity is collectively
described as lipase. Serum lipase derives primarily
from pancreatic lipase, which is secreted into the
duodenum and participates in fat digestion.
Pancreatic lipase is quite distinct from lipoprotein
lipases, which clear the blood of chylomicrons after
fats are absorbed.
Viral hepatitis and disorders in which bile salts are
decreased may produce low serum lipase levels, as
will protamine and IV infusions of saline.
Reference Values

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter serum amylase
levels, a medication history should be obtained. It
is recommended that any drugs that may alter test
results be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any drugs withheld before the test, pending test results.
Abnormal values: Note and report increased
levels. Correlate with urine amylase, hypocalcemia, hypokalemia, hyperglycemia, and bilirubin
in relation to pancreatic diseases. Assess for fluid
deficit if pancreatic hemorrhage is present, severity of abdominal pain if acute inflammation is
present, jaundice if common bile duct is
obstructed, and bowel sounds. Maintain nothing
by mouth (NPO) status and prepare client for IV

All groups

Conventional Units

SI Units

0–160 U/L

0–2.72 kat/L

INTERFERING FACTORS

Morphine, cholinergic drugs, and heparin may
lead to elevated levels.
Protamine and IV infusions of saline may lead to
decreased levels.
INDICATIONS FOR SERUM LIPASE TEST

Diagnosis of acute pancreatitis, especially if the
client has been ill for more than 3 days:
Serum amylase levels may return to normal
after 3 days, but serum lipase remains elevated
for approximately 10 days after onset.
Support for diagnosing pancreatic carcinoma,
especially if there is a sustained moderate elevation in serum lipase levels
Support for diagnosing other disorders associated with elevated serum lipase levels (e.g.,
peptic ulcer, acute cholecystitis, and early renal
failure)
Support for diagnosing disorders associated with
decreased serum lipase levels (e.g., advanced
chronic pancreatitis, cystic fibrosis, advanced
carcinoma of the pancreas, and viral hepatitis)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving collection of a peripheral blood sample
(see Appendix I).

CHAPTER 5—Blood

Chemistry

149

Reference Values
Conventional Units
Newborns

10.4–16.4 U/L

1 mo–13 yr

0.5–11.0 U/L (King-Armstrong)

Adults

SI Units

6.4–15.2 U/L

108.0–258.0 kat/L

0–0.8 U/L

0.0–14.0 kat/L

0.1–2.0 U/L (Gutman)
0.5–2.0 U/L (Bodansky)
0.1–5.0 U/L (King-Armstrong)
0.1–0.8 U/L (Bessey-Lowry)
0–0.56 U/L (Roy)
The client should fast from food for at least 8
hours before the test.
It is recommended that drugs that may alter test
results be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume food and any drugs withheld before the
test.

Acid Phosphatase
Phosphatases are enzymes that cleave phosphate
from compounds with a single phosphate group.
Those that are optimally active at pH 5 are grouped
under the name acid phosphatase (ACP).
Many tissues (kidneys, spleen, liver, bone) contain
ACP, but the prostate gland, red blood cells (RBCs),
and platelets are especially rich in this activity. Two
isoenzymes, prostatic fraction and RBC/platelet
fraction, are diagnostically significant. These isoenzymes differ from one another in preferred substrate
and in the degree to which they are inhibited by various additives during laboratory testing. Normal
serum contains more RBC/platelet than prostatic
ACP, and small changes in prostatic fraction may be
difficult to detect. Tartaric acid inhibits prostatic

ACP. Thus, many laboratories report tartrateinhibitable ACP as well as total ACP in an effort to
focus more specifically on the prostatic fraction.
Decreased levels of prostatic ACP are seen after
estrogen therapy for prostatic carcinoma and in
clients with Down syndrome. Decreased levels are
associated with ingestion of alcohol, fluorides,
oxalates, and phosphates.
Administration of androgens in women and of
clofibrate in both genders produces elevated levels.
INTERFERING FACTORS

Prostatic massage or rectal examination within 48
hours of the test may cause elevated levels.
Administration of androgens in females and of
clofibrate in either gender may produce elevated
levels.
Ingestion of alcohol, fluorides, oxalates, and phosphates may result in decreased levels.
INDICATIONS FOR SERUM ACID PHOSPHATASE
TEST

Enlarged prostate gland, especially if prostatic
carcinoma is suspected:
Prostatic ACP is elevated in 50 to 75 percent of
individuals with prostatic carcinoma that has
extended beyond the gland.
Cancers that remain within the gland cause
ACP elevation in only 10 to 25 percent of those
affected.
Benign hyperplasia, inflammation, or ischemic
damage to the prostate rarely causes elevated
ACP levels.
Evaluation of the effectiveness of treatment of
prostatic carcinoma:
ACP levels fall to normal within 3 to 4 days of
successful estrogen therapy.

150

SECTION I—Laboratory

Tests

Recurrent elevation strongly suggests that bone
metastases are active.
Support for diagnosing other disorders associated
with elevated prostatic ACP levels (e.g., metastatic
bone cancer, Paget’s disease, osteogenesis imperfecta, hyperparathyroidism, and multiple
myeloma)
Known or suspected hematologic disorder:
Elevated RBC/platelet ACP is seen in hemolytic
anemia, sickle cell crisis, thrombocytosis, and
acute leukemia.
Support for diagnosing other disorders associated
with increased RBC/platelet ACP (e.g., renal
insufficiency, liver disease, Gaucher’s disease, and
Niemann-Pick disease)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of a peripheral blood sample
(see Appendix I).
It is recommended that any drugs that may alter
test results be withheld for 12 to 24 hours before
the test, although this practice should be
confirmed with the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory. If the test cannot
be performed within a few hours, the serum should
be frozen.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any drugs withheld before the test.
Abnormal values: Note and report increased
levels or associated levels of prostate-specific antigen. Provide support in coping with a life-threatening disease, hormonal therapy, and possible
surgical procedure.

Prostate-Specific Antigen
Prostate-specific antigen (PSA) is a glycoprotein
found in the prostate tissues. Its presence is tested by
immunoassay techniques to assist in the detection of
prostatic carcinoma. It is considered to be a more
specific immunohistochemical marker for metastatic tumor of prostate origin than is ACP. ACP is a test
also performed to diagnose prostatic carcinoma, but
it is not entirely specific for this disease, because
increased values have been noted in bladder as well

as in prostatic carcinoma. Increased levels of PSA
correlate with the amount of prostatic tissue, both
malignant and benign.
Reference Values
Conventional Units

SI Units

Men 40 yr

2.0 ng/mL

2.0 g/L

Men 40 yr

2.8 ng/mL

2.8 g/L

INTERFERING FACTORS

Prostatic massage or rectal examination within 48
hours of the test can cause elevated levels.
INDICATIONS FOR PROSTATE-SPECIFIC ANTIGEN
TEST

Screening for early detection of prostate carcinoma and evaluating those who are at risk for this
disease, primarily men over 40 years of age
Diagnosing a malignant tumor of the prostate
gland, revealed by increased levels, depending on
the volume of the tumor
Determining chemotherapeutic regimen protocol
or radiation therapy and monitoring and evaluating the response to therapy, revealed by a decrease
in the PSA level
Evaluating progression or recurrence of the
tumor, revealed by a rise in the PSA level
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The age of the client
should be noted on the laboratory form. The sample
should be refrigerated if the test is not performed
within 24 hours.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

Aldolase
Aldolase (ALS) is a glycolytic enzyme that catalyzes
the breakdown of 1,6-diphosphate into triose phosphate. It is found in many body tissues but is most
diagnostically significant in disorders of skeletal and
cardiac muscle, liver, and pancreas. Three isoen-

CHAPTER 5—Blood

Chemistry

151

Reference Values
Conventional Units

SI Units

Newborns

5.2–32.8 U/L (Sibley-Lehninger)

0.09–0.54 kat/L

Children

2.6–16.4 U/L (Sibley-Lehninger)

0.04–0.27 kat/L

Adults

1.3–8.2 U/L (Sibley-Lehninger)

0.02–0.14 kat/L

Men

3.1–7.5 U/L at 98.6 F (37 C)

0.05–0.13 kat/L

Women

2.7–5.3 U/L at 98.6 F (37 C)

0.04–0.09 kat/L

zymes have been identified: A, originating in skeletal
and cardiac muscle; B, originating in liver, kidneys,
and white blood cells; and C, originating in brain
tissue. Isoenzyme C probably lacks diagnostic capability because it does not cross the blood–brain
barrier.

involving collection of a peripheral blood sample
(see Appendix I).
It is recommended that drugs that may alter test
results be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.

INTERFERING FACTORS

THE PROCEDURE

Hepatotoxic drugs, insecticides, and anthelminthics may cause elevated levels.
Phenothiazines may cause decreased levels.
INDICATIONS FOR ALDOLASE TEST

Family history of Duchenne’s muscular dystrophy:
ALS levels rise before clinical signs appear, thus
permitting early diagnosis.
Signs and symptoms of neuromuscular disorders,
to differentiate muscular disorders from neurological disorders:
Pronounced elevations are seen in clients
having Duchenne’s muscular dystrophy,
polymyositis, dermatomyositis, trichinosis, and
severe crush injuries.
Decreased aldolase levels are seen in those with
late muscular dystrophy, because of loss of
muscle cells, or with use of phenothiazines.
ALS is not elevated in those with multiple sclerosis or myasthenia gravis, both of which are of
neural origin.
Support for diagnosing other disorders associated
with elevated ALS levels:
Moderate increases are associated with acute
hepatitis, neoplasms, and leukemia.
Mild elevations are seen in acute myocardial
infarction (peak elevation occurs in 24 hours,
with gradual return to normal within 1 week).
Evaluation of response to exposure to hepatotoxic
drugs or chemicals, with liver damage indicated
by elevated levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any drugs withheld before the test.
Abnormal values: Note and report increased
levels related to skeletal muscular disorders. Assess
for muscle fatigue and strength related to an acute
or chronic disorder. Provide energy-saving care to
conserve the client’s energy while still maintaining
as much independence as possible. Instruct in a
planned rest and exercise program.

Creatine Phosphokinase and
Isoenzymes
Creatine phosphokinase (CPK), also called creatine
kinase (CK), catalyzes the reversible exchange of
phosphate between creatine and adenotriphosphate
(ATP). Important in intracellular storage and release
of energy, CPK exists almost exclusively in skeletal
muscle, heart muscle, and, to a lesser extent, brain.
No CPK is found in the liver. Anything that damages
skeletal or cardiac muscle elevates serum CPK levels.
Brain injury affects serum CPK levels much less,
probably because relatively little enzyme crosses the
blood–brain barrier.
Spectacular CPK elevations occur in the early
phases of muscular dystrophy, but CPK elevation
diminishes as the disease progresses and muscle

152

SECTION I—Laboratory

Tests

•

Causes of Elevated
Creatine Phosphokinase

TABLE 5–20

Pronounced Elevation (5 or more times normal)
Early muscular dystrophy (CPK-MM, CPK3)
Acute myocardial infarction (CPK-MB, CPK2)
Severe angina (CPK-MB, CPK2)
Polymyositis (CPK-MM, CPK3)
Cardiac surgery
Moderate Elevation (2–4 times normal)
Vigorous exercise
Deep intramuscular injections
Surgical procedures affecting skeletal muscles
Delirium tremens
Convulsive seizures
Dermatomyositis
Alcoholic myopathy
Hypothyroidism
Pulmonary infarction
Acute agitated psychosis
Mild Elevation (up to 2 times normal)
Late pregnancy
Women heterozygous for the gene causing
Duchenne’s muscular dystrophy (CPK-MM, CPK3)
Brain injury (CPK-BB, CPK1)
Adapted from Sacher, RA, and McPherson, RA:
Widmann’s Clinical Interpretation of Laboratory
Tests, ed 11. FA Davis, Philadelphia, 2000, p. 536,
with permission.

mass decreases. Levels of CPK may be normal to low
in late, severe cases. Additional causes of elevated
CPK, and the magnitude of those elevations, are
listed in Table 5–20.
The CPK molecule consists of two parts, which
may be identical or dissimilar. These two constituent
chains are called M (muscle) and B (brain). Three
diagnostically significant isoenzymes have been
identified in relation to the two main components of
CPK. Brain CPK (CPK-BB, CPK1) is almost entirely
BB, cardiac CPK (CPK-MB, CPK2) contains 60
percent MM and 40 percent MB, and skeletal muscle
CPK (CPK-MM, CPK3) contains about 90 percent
MM and 10 percent MB. The isoenzyme normally
present in serum is almost entirely MM, and only
CPK-MM (CPK3) rises when skeletal muscle is

damaged. In contrast, serum CPK-MB (CPK2) rises
only when heart muscle is damaged.
Drugs that may produce elevated CPK levels
include anticoagulants, morphine, alcohol, salicylates in high doses, amphotericin-B, clofibrate, and
certain anesthetics. Any medication administered
intramuscularly (IM) also elevates CPK. In addition
to late muscular dystrophy, decreased levels are seen
in early pregnancy.
Myoglobin is an oxygen-carrying protein
normally found in cardiac and skeletal muscle. In
acute myocardial infarction (AMI), myoglobin levels
rise within 1 hour. Although myoglobin alone is not
particularly sensitive to cardiac damage, in conjunction with CPK-MB it has a diagnostic capability
approaching 100 percent in correctly identifying
AMI.29 See Table 5–21.
INTERFERING FACTORS

Vigorous exercise, deep intramuscular (IM) injections, delirium tremens, and surgical procedures
in which muscle is transected or compressed may
produce elevated levels.
Drugs that may produce elevated CPK levels
include anticoagulants, morphine, alcohol, salicylates in high doses, amphotericin-B, clofibrate,
and certain anesthetics.
Early pregnancy may produce decreased levels.
INDICATIONS FOR CREATINE PHOSPHOKINASE
AND ISOENZYMES TEST

Signs and symptoms of acute myocardial infarction:
Acute myocardial infarction releases CPK into
the serum within the first 48 hours, and values
return to normal in about 3 days.
CPK levels rise before aspartate aminotransferase and lactic dehydrogenase levels rise.
The isoenzyme CPK-MB (CPK2) rises only
when the heart muscle is damaged; it appears
in the first 6 to 24 hours and is usually gone in
72 hours.
Both total CPK and MB fraction may rise in
severe angina or extensive reversible ischemic
damage.30
Recurrent elevation of CPK suggests reinfarction or extension of ischemic damage.
An elevated CPK level helps to differentiate
myocardial infarction from CHF and conditions associated with liver damage.
Family history of Duchenne’s muscular dystrophy:
Spectacular CPK elevations occur in the early
phases of muscular dystrophy, even before clinical signs or symptoms appear.

CHAPTER 5—Blood

Chemistry

153

Reference Values
Conventional Units

SI Units

Total CPK
Newborns

30–100 U/L

0.51–1.70 kat/L

Children

15–50 U/L

0.26–0.85 kat/L

5–55 U/L

—

55–170 U/L

0.94–2.89 kat/L

5–35 g/mL

—

5–25 U/L

—

30–135 U/L

0.51–2.30 kat/L

5–25 g/mL

—

CPK-BB (CPK1)

0% of total CK

—

CPK-MB (CPK2)

0–7% of total CK

—

CPK-MM (CPK3)

5–70% of total CK

—

Myoglobin

100 ng/mL

100 nmol/L

Adults
Men

Women

Isoenzymes

Image/Text rights unavailable

154

SECTION I—Laboratory

Tests

Image/Text rights unavailable
CPK elevation diminishes as the disease
progresses and muscle mass decreases.
Signs and symptoms of other disorders associated
with elevated CPK levels (see Table 5–20)
NURSING CARE BEFORE THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.

Troponin Levels
Differential diagnosis of chest pain remains problematic. It is estimated that 12 percent of patients
with AMI are sent home from the emergency
department.31 Traditional measures to diagnose
AMI include an ECG and measurement of cardiac
enzymes, particularly creatine kinase CK-MB.32 In
recent years, troponin levels have been studied to
determine the efficacy of this laboratory test in diagnosis of AMI. Troponin is a protein found in striated
muscle. There are three specific types: troponin-C
(TnC), troponin-I (TnI), and troponin-T (TnT).
TnT and TnI are specific for cardiac disease, and
several studies have concluded that elevated levels of
these enzymes result in greater sensitivity in diagnosing AMI and determining comprehensive risk
stratification of patients with unstable angina.31,33,34
TnT and TnI will be elevated within 4 hours after
myocardial damage and remain elevated for 10 to 14
days.
Reference Values

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any study involving the collection
of a peripheral blood sample.
Resume any drugs withheld before the test, as well
as usual activities.
Abnormal values: Note and report increased
levels of CPK, CPK-MB, lactic dehydrogenase (in
relation to myocardial infarction), and CPK-MM
(in relation to muscular dystrophy). Monitor vital
signs. Monitor ECG for dysrhythmias. Monitor
for fluid overload (distended neck veins, dyspnea,
crackles on auscultation). Repeat ordered CPK
and lactic dehydrogenase enzyme and isoenzyme
tests.

Presence of cardiac enzyme marker
INTERFERING FACTORS

TnT may be present in renal failure.
INDICATIONS FOR TROPONIN LEVELS TEST

Diagnosis and risk stratification for unstable
angina
Diagnosis of AMI
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any study
involving the collection of a peripheral blood sample
(see Appendix I).

CHAPTER 5—Blood

Chemistry

155

Reference Values
Conventional Units
Total LDH

SI Units

80–120 U (Wacker) @ 636 F (300 C)
150–450 U (Wroblewski)

1.21–3.52 kat/L

71–207 U/L
LDH Isoenzymes

Percentage of Total

Fraction of Total

LDH1

29–37%

0.29–0.37

LDH2

42–48%

0.42–0.48

LDH3

16–20%

0.16–0.20

LDH4

2–4%

0.02–0.04

LDH5

0.5–1.5%

0.005–0.015

Note: Values may vary according to the laboratory performing the test.

THE PROCEDURE

A venipuncture is performed and the sample is
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and sent
promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

Lactic Dehydrogenase and
Isoenzymes
Lactic dehydrogenase (LDH) catalyzes the reversible
conversion of lactic acid to pyruvic acid within cells.
Because many tissues contain LDH, elevated total
LDH is considered a nonspecific indication of cellular damage unless other clinical data make the tissue
origin obvious. Pronounced elevations in total LDH
are seen in clients with megaloblastic anemia,
metastatic cancer (especially if the liver is involved),
shock, hypoxia, hepatitis, and renal infarction.
Moderate elevations occur in those with myocardial
and pulmonary infarctions, hemolytic conditions,
leukemias, infectious mononucleosis, delirium
tremens, and muscular dystrophy. Mild elevations
are associated with most liver diseases, nephrotic
syndrome, hypothyroidism, and cholangitis.
The most useful diagnostic information is
obtained by analyzing the five isoenzymes of LDH
through electrophoresis. These isoenzymes are
specific to certain tissues. The heart and erythrocytes
are rich sources of LDH1 and LDH2; however, the

brain is a source of LDH1, LDH2, and LDH3. The
kidneys contain LDH3 and LDH4; the liver and
skeletal muscle contain LDH4 and LDH5. Certain
glands (thyroid, adrenal, and thymus), pancreas,
spleen, lungs, lymph nodes, and white blood cells
contain LDH3, whereas the ileum is an additional
source of LDH5.
Situations in which isoenzyme analysis is most
useful include distinguishing myocardial infarction
from lung or liver problems, diagnosing myocardial
infarction in ambiguous settings such as the postoperative period or during severe shock and in hemolysis at a time of bone marrow hypoplasia.
Normally, serum contains more LDH2 than
LDH1. Damage to tissues rich in LDH1, however, will
cause this ratio to reverse. The reversed ratio (i.e.,
LDH2 greater than LDH2) is an important diagnostic finding that occurs whether or not total LDH is
elevated. The reversal is short lived. In myocardial
infarction, for example, the LDH1:LDH2 ratio
returns to normal within a week of the infarction
even though total LDH may remain elevated.35 The
tissue sources of LDH isoenzymes and common
causes of elevations are summarized in Table 5–21.
Numerous drugs may elevate LDH levels:
anabolic steroids, anesthetics, aspirin, alcohol, fluorides, narcotics, clofibrate, mithramycin, and
procainamide.
INTERFERING FACTORS

Numerous drugs may produce elevated LDH
levels (e.g., anabolic steroids, anesthetics, aspirin,
alcohol, fluorides, narcotics, clofibrate, mithramycin, and procainamide).

156

SECTION I—Laboratory

Tests

INDICATIONS FOR LACTIC DEHYDROGENASE
AND ISOENZYMES TEST

Confirmation of AMI or extension thereof, as
indicated by elevation (usually) of total LDH,
elevation of LDH1 and LDH2, and reversal of the
LDH1:LDH2 ratio within 48 hours of the infarction
Differentiation of acute myocardial infarction
from pulmonary infarction and liver problems,
which elevate LDH4 and LDH5
Confirmation of red blood cell hemolysis or renal
infarction, especially as indicated by reversal of
the LDH1:LDH2 ratio
Confirmation of chronicity in liver, lung, and
kidney disorders, as evidenced by LDH levels that
remain persistently high
Evaluation of the effectiveness of cancer
chemotherapy (LDH levels should fall with
successful treatment.)
Evaluation of the degree of muscle wasting in
muscular dystrophy (LDH levels rise early in this
disorder and approach normal as muscle mass is
reduced by atrophy.)
Signs and symptoms of other disorders associated
with elevation of the several LDH isoenzymes (see
Table 5–21)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of a peripheral blood sample
(see Appendix I).
It is recommended that drugs that may alter test
results be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.

mental and physical development of the infant, with
death resulting by the third or fourth year of life. The
deficiency of this enzyme is most common in families of Eastern-European Jewish and FrenchCanadian origin. Because of this deficiency,
gangliosides or complex sphingolipids are not
metabolized and accumulate in the brain, causing
the paralysis, blindness, dementia, and mental retardation that develop in the children who have this
disorder.36
Reference Values
56–80 percent of a total normal level
(10.4–23.8 U/L)
INTERFERING FACTORS

Pregnancy decreases the level of hexosaminidase
in relation to the total, resulting in an inaccurate
false positive.
Oral contraceptives can decrease the level.
INDICATIONS FOR HEXOSAMINIDASE TEST

Screening young adults for asymptomatic possession of this gene with or without a family history
of Tay-Sachs disease
Identifying carriers in high-risk clients during
prenatal examination, revealed by a lowered
enzyme activity
Diagnosing Tay-Sachs in infants, revealed by a
very low level or absence of enzyme activity
In utero prenatal diagnosis of amniotic fluid or
cells obtained from chorionic villi
NURSING CARE BEFORE THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.

Client preparation is the same as that for any test
involving the collection of a peripheral blood sample
(see Appendix I).
Food and fluids should be avoided for 8 hours
before the test, and oral contraceptives should be
withheld.

NURSING CARE AFTER THE PROCEDURE

THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any drugs withheld before the test.

A venipuncture is performed and the sample
collected in a red-topped tube. Refer to the procedures to obtain prenatal samples via chorionic villus
biopsy or amniocentesis (see Chapters 10 and 14).

THE PROCEDURE

NURSING CARE AFTER THE PROCEDURE

Hexosaminidase
Hexosaminidase A is a test performed to determine
the presence of the lysosomal disease known as TaySachs, a genetic autosomal recessive condition characterized by early and progressive retardation in the

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any drugs withheld before the test.
Complications and precautions: Recommend

CHAPTER 5—Blood

special genetic counseling for those with a family
history of the disease or with abnormal test
results.

-Hydroxybutyric Dehydrogenase
-Hydroxybutyric dehydrogenase (-HBD, HBD) is
an enzyme similar to two isoenzymes of lactic dehydrogenase: LDH1 and LDH2. The -HBD test,
however, is cheaper and easier to perform than LDH
isoenzyme electrophoresis. Moreover, HBD levels
remain elevated for 18 days after acute myocardial
infarction, providing a diagnosis when the client has
delayed seeking treatment or has not had classic
signs and symptoms.
Reference Values
Conventional Units
70–300 U/L
140–350 U/L
Note: Values may vary according to the laboratory performing the test.
INDICATIONS FOR -HYDROXYBUTYRIC
DEHYDROGENASE TEST

Suspected “silent” myocardial infarction or otherwise atypical myocardial infarction in which the
client delayed seeking care:
HBD levels remain elevated for 18 days after
acute myocardial infarction (i.e., when other
cardiac enzymes have returned to normal
levels).
Support for diagnosing other disorders associated
with elevated HBD levels (e.g., megaloblastic and
hemolytic anemias, leukemias, lymphomas,
melanomas, muscular dystrophy, nephrotic
syndrome, and acute hepatocellular disease)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test

Chemistry

157

involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

Cholinesterases
Cholinesterases hydrolyze concentrated acetylcholine and also cleave other choline esters. Two
types of cholinesterase are measured: (1) acetylcholinesterase (“true” cholinesterase) and (2)
pseudocholinesterase. Acetylcholinesterase (AcCHS)
is found at nerve endings and in erythrocytes; very
little is found in serum. Its substrate specificity is
limited to acetylcholine, and it is optimally active
against very low acetylcholine concentrations.
Pseudocholinesterase (PCE) derives from the liver
and is normally found in the serum in substantial
amounts. It is active against acetylcholine and other
choline esters. PCE is unusual in that the diagnostically significant change is depression, not elevation.
An important application of information about
PCE is in evaluating individuals for genetic variations of the enzyme before surgery in which
succinylcholine, an inhibitor of acetylcholine, is to
be used to induce anesthesia. Persons homozygous
for the abnormal form of PCE have depressed total
serum activity and their enzyme does not inactivate
succinylcholine; persons who receive the drug
during surgery may experience prolonged respiratory depression. Presence of the abnormal form of
PCE is determined by exposing the enzyme to dibucaine. Normal PCE is inhibited by dibucaine,

Reference Values
Conventional Units

SI Units

Acetylcholinesterase (AcCHS)

0.5–1.0 pH units

Pseudocholinesterase (PCE)

0.5–1.3 pH units

Men

274–532 IU/dL

2.74–5.32 kU/L

Women

204–500 IU/dL

2.04–5.00 kU/L

158

SECTION I—Laboratory

Tests

whereas abnormal PCE is found to be “dibucaine
resistant.”37
INTERFERING FACTORS

Numerous drugs may falsely decrease
cholinesterase levels (e.g., caffeine, theophylline,
quinidine, quinine, barbiturates, morphine,
codeine, atropine, epinephrine, phenothiazines,
folic acid, and vitamin K).
INDICATIONS FOR CHOLINESTERASE
DETERMINATIONS

collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.

Renin

Suspected exposure to organic phosphate insecticides:
Red blood cell AcCHS levels decline with severe
exposure; serum PCE decreases occur earlier.
When exposure ceases, serum PCE rises before
red blood cell AcCHS returns to normal.
Red blood cell AcCHS levels are more useful
than are serum PCE levels in determining prior
exposure.
Impending use of succinylcholine during anesthesia:
Persons homozygous for the abnormal form of
PCE have depressed total serum activity, and
their enzyme does not inactivate succinylcholine, with the abnormal PCE indicated as
“dibucaine resistant.”
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter cholinesterase
levels and activity, a medication history should be
obtained. It is recommended that those drugs that
may alter test results be withheld for 12 to 24
hours before the test, although this practice
should be confirmed with the person ordering the
study.

Renin is an enzyme released by the juxtaglomerular
apparatus of the kidney in response to decreased
extracellular fluid volume, serum sodium, and renal
perfusion pressure. It catalyzes the conversion of
angiotensinogen, produced by the liver, to angiotensin I. Angiotensin I is then converted to angiotensin II in the lungs. Angiotensin II elevates
systemic blood pressure by causing vasoconstriction
and by stimulating the release of aldosterone.
Renin released by the kidneys is found initially in
the renal veins. Thus, the output of renin by each
kidney may be determined by obtaining samples
directly from the right and left renal veins and
comparing the results with those obtained from an
inferior vena cava sample. This test is indicated
when renal artery stenosis is suspected, because the
kidney affected by decreased perfusion releases
higher amounts of renin. Renal vein assay for renin
is performed using fluoroscopy and involves cannulation of the femoral vein and injection of dye to aid
in visualizing the renal veins. Because this is an invasive procedure, a signed consent is required.
INTERFERING FACTORS

THE PROCEDURE

A venipuncture is performed and the sample

Failure to follow dietary restrictions, if ordered,
before the test may affect the test results.
Failure to take prescribed diuretics, if ordered,
before the test may affect the test results.
Failure to maintain required positioning (e.g.,
upright versus recumbent) for at least 2 hours
before the test may affect the test results.

Reference Values

Peripheral vein

Conventional Units

SI Units

0.4–4.5 (ng/hr)/mL (normal salt intake, standing position)

0.4–4.5 gh–1 L–1

1.5–1.6 (ng/hr)/mL or more (normal salt intake, supine position)

1.5–1.6 gh–1 L–1

Renal vein assay Difference between each renal sample and the vena cava sample should be 1.4–1.0
Note: Values for peripheral vein samples should be substantially higher (e.g., 2.9–24 [ng/hr]/mL) in clients who are sodium
depleted and in the upright position. These values also may vary according to the laboratory performing the test.

CHAPTER 5—Blood

High-dose adrenocorticosteroid therapy, excessive
salt intake, and excessive licorice ingestion may
produce decreased levels.
INDICATIONS FOR RENIN TEST

Assessment of renin production by the kidneys
when client has hypertension of unknown etiology or when other disorders associated with
altered renin levels are suspected:
Elevated renin levels are seen in renovascular
and malignant hypertension, adrenal hypofunction (Addison’s disease), salt-wasting
disorders, end-stage renal disease, reninproducing renal tumors, and secondary hyperaldosteronism.
Decreased levels are associated with primary
hyperaldosteronism, hypervolemia, excessive
salt ingestion or retention, excessive adrenocorticosteroid levels resulting from either disease
or drug therapy, and excessive licorice ingestion.
Renin levels may be high, low, or normal in
essential hypertension.
In primary hyperaldosteronism, plasma renin
levels are decreased, even with salt depletion
before the test (results should be evaluated in
relation to the serum aldosterone level, which is
elevated in primary hyperaldosteronism).
Suspected renal artery stenosis as the cause of
hypertension, as indicated by renal vein output
of renin by the affected kidney more than 1.4
times that of the vena cava sample
Nursing Alert

The renal vein assay for renin should be
performed with extreme caution, if at all, in
clients with allergies or previous exposure to
radiographic dyes.
NURSING CARE BEFORE THE PROCEDURE

Client preparation varies according to the method
for obtaining the sample and the factors to be
controlled (e.g., salt depletion).
1. Peripheral vein, normal salt intake. Client
preparation is essentially the same as that
for any test involving collection of a peripheral blood sample. The client should follow
a normal diet with adequate salt and potassium intake. Licorice intake and certain
medications may be restricted for 2 weeks or
more before the test, although this practice
should be confirmed with the person ordering
the study. The position relevant to the type of

Chemistry

159

sample (e.g., upright versus recumbent)
should be maintained for 2 hours before the
test.
2. Peripheral vein, sodium depleted. Client preparation is the same as just described, except that
a diuretic is administered for 3 days before the
study and dietary sodium is limited to “no
added salt” (approximately 3 g/day). Sample
menus should be provided. The purpose of the
diuretic therapy and sodium restriction should
be explained, and client understanding and
ability to follow pretest preparation should be
ascertained.
Explain to the client:
The purpose of the study
That a “no added salt” diet must be followed for
3 days before the study
That prescribed diuretics must be taken for 3 days
before the study
Other restrictions in diet (e.g., licorice) or drugs
necessary before the study
That the test will be performed in the radiology
department by a physician and will take about 30
minutes
The general procedure, including the sensations
to expect (momentary discomfort as the local
anesthetic is injected, sensation of warmth as the
dye is injected)
Whether premedications will be given
After-procedure assessment routines (e.g.,
frequent vital signs) and activity restrictions
Encourage questions and verbalization of concerns
appropriate to the client’s age and mental status.
Then:
Question the client about possible allergies to
radiographic dyes.
Ensure that signed consent has been obtained.
To the extent possible, ensure that the dietary and
medication regimens and restrictions are
followed.
Assist the client in maintaining the upright position (standing or sitting) for 2 hours before the
test, if ordered, to stimulate renin secretion.
Take and record vital signs and have the client
void; provide a hospital gown.
Administer premedication, if ordered.
Obtain a stretcher for client transport.
THE PROCEDURE

The procedure varies with the method for obtaining the sample.
1. Peripheral vein. A venipuncture is performed
and the sample collected in a chilled lavendertopped tube. The tube should be inverted
gently several times to promote adequate

160

SECTION I—Laboratory

Tests

mixing with the anticoagulant, placed in ice,
and sent to the laboratory immediately.
2. Renal vein. The client is assisted to the supine
position on the fluoroscopy table, and a site is
selected for femoral vein catheterization. The
skin may be shaved (if necessary), cleansed
with an antiseptic, draped with sterile covers,
and injected with a local anesthetic.
A catheter is inserted into the femoral vein and
advanced to the renal veins under fluoroscopic
observation. Radiographic dye may be injected into
the inferior vena cava at this point to aid in identification of the renal veins. A renal vein is entered and
a blood sample obtained. The other renal vein is
then entered and a second blood sample obtained.
The catheter is then retracted into the inferior vena
cava and a third sample obtained.
The samples are placed in chilled lavender-topped
tubes that are labeled to identify collection sites.
The tubes should be inverted gently several times
to promote adequate mixing with the anticoagulant, placed in ice, and sent to the laboratory immediately.
The femoral catheter is removed after the third
sample is obtained, and pressure is applied to the site
for 10 minutes. A pressure dressing is then applied.
NURSING CARE AFTER THE PROCEDURE

1. Peripheral vein. Care and assessment after the
procedure are the same as for any study involving the collection of a peripheral blood
sample. Pretest diet and medications, which
may have been modified or restricted before
the study, should be resumed.
2. Renal vein. Maintain the client on bed rest for
8 hours after the procedure. Monitor vital
signs and record according to the following
schedule: every 15 minutes for 1 hour, every 30
minutes for 1 hour, and every hour for 4 hours.
Monitor the catheterization site for bleeding or
hematoma each time vital signs are checked.
Resume previous diet and medications.
Abnormal values: Note and report results and
correlate with urinary sodium, serum, and
urinary aldosterone. Monitor blood pressure,
especially if antihypertensive medications have
been withheld. Monitor I&O for fluid deficit or
excess.
Allergic response (renal vein): Note and report
allergic response to dye injection and assess for
rash, urticaria, dyspnea, and tachycardia.
Administer ordered antihistamine or steroids and
oxygen. Have emergency equipment and supplies
on hand.
Vein thrombosis (renal vein): Note and report

any flank or back pain, hematuria, or abnormal
renal test results (blood urea nitrogen, creatinine).

HORMONES
Hormones are chemicals that control the activities
of responsive tissues. Some hormones exert their
effects in the vicinity of their release; others are
released into the extracellular fluids of the body and
affect distant tissues. Similarly, some hormones
affect only specific tissues (target tissues), whereas
others affect nearly all cells of the body. Chemically,
hormones are classified as polypeptides, amines, and
steroids.
Hormones act on responsive tissues by (1) altering the rate of synthesis and secretion of enzymes or
other hormones, (2) affecting the rate of enzymatic
catalysis, and (3) altering the permeability of cell
membranes. Once the hormone has accomplished
its function, its rate of secretion normally decreases.
This is known as negative feedback. After sufficient
reduction in hormonal effects, negative feedback
decreases, and the hormone is again secreted.

Hypophyseal Hormones
The hypophysis, also known as the pituitary gland,
lies at the base of the brain in the sella turcica and is
connected to the hypothalamus by the hypophyseal
stalk. The hypophysis has two distinct portions: (1)
the adenohypophysis (anterior pituitary) and (2) the
neurohypophysis (posterior pituitary). The adenohypophysis arises from upward growth of pharyngeal epithelium in the embryo, whereas the
neurohypophysis arises from the downward growth
of the hypothalamus in the embryo.
Almost all hormonal secretion from the hypophysis is controlled by the hypothalamus. Neurohypophyseal hormones are formed in the
hypothalamus and travel down nerve fibers to the
neurohypophysis, where they are stored and then
released into the circulation in response to feedback mechanisms. Adenohypophyseal hormone
secretion is controlled by releasing and inhibiting
factors that are secreted by the hypothalamus and
carried to the adenohypophysis by the hypothalamic–hypophyseal portal vessels. Hypothalamic
releasing and inhibiting factors identified thus far
include (1) thyrotropin-releasing hormone (TRH);
(2) corticotropin-releasing hormone (CRH); (3)
gonadotropin-releasing hormone (GnRH), also
known as luteinizing hormone–releasing hormone
(LHRH) and follicle-stimulating hormone–releasing factor; (4) growth hormone–releasing hormone
(GHRH); (5) growth hormone–inhibiting hormone

CHAPTER 5—Blood

(GHIH); and (6) prolactin inhibitory hormone
(PIH). A releasing factor for melanocyte-stimulating
hormone also is believed to exist. The releasing
factors either stimulate or inhibit the adenohypophysis in the release of its hormones.
The adenohypophysis consists of three major cell
types: (1) acidophils, (2) basophils, and (3) chromophobes. The acidophils secrete growth hormone
(GH), also called somatotropic hormone (STH, SH)
or somatotropin, and prolactin (HPRL), also known
as luteotropic hormone (LTH), lactogenic hormone,
or lactogen. The basophils secrete adrenocorticotropic hormone (ACTH), also known as adrenocorticotropin and corticotropin; thyroid-stimulating
hormone (TSH), also known as thyrotropin; folliclestimulating hormone (FSH); luteinizing hormone
(LH), also known as interstitial cell–stimulating
hormone (ICSH); and melanocyte-stimulating
hormone (MSH). The chromophobes, which constitute about half of the adenohypophyseal cells, are
resting cells capable of transformation to either
acidophils or basophils.
The hormones stored and released by the neurohypophysis include antidiuretic hormone (ADH),
also known as vasopressin, and oxytocin. Radioimmunoassays are used to determine the blood
levels of the hypophyseal hormones.

GROWTH HORMONE
Growth hormone (GH, STH, SH) is secreted in
episodic bursts, usually during early sleep. The
effects of GH occur throughout the body. GH
promotes skeletal growth by stimulating hepatic
production of proteins. It also affects lipid and
glucose metabolism. Under the influence of growth
hormone, free fatty acids enter the circulation for
use by muscle; hepatic glucose production (gluconeogenesis) also rises. Growth hormone also
increases blood flow to the renal cortex and the
glomerular filtration rate; the kidney excretes more
calcium and less phosphate than usual. GH is
believed to antagonize insulin.
Deficiencies in GH are apparent only in childhood. Children with GH deficiency have very small
statures but normal body proportions. The child
also may be deficient in other hypophyseal
hormones, and this disorder is known as pituitary
dwarfism.
Excessive levels of GH are apparent in all ages.
Excess GH in children causes the long bones of the
skeleton to enlarge and produces gigantism. In
adults, the bones of the skull, hands, and feet thicken
to produce the physical appearance of acromegaly.
In this disorder, the internal organs, skeletal muscle,

Chemistry

161

and heart muscle hypertrophy. Nerves and cartilage
also enlarge and may produce nerve compression
and joint disorders.
Reference Values
Conventional Units

SI Units

Newborns

15–40 ng/mL

15–40 g/L

Children

0–10 ng/mL

0–10 g/L

Adults

0–10 ng/mL

0–10 g/L

Note: Values may vary according to the laboratory
performing the test.

INTERFERING FACTORS

Hyperglycemia and therapy with drugs such as
adrenocorticosteroids and chlorpromazine may
cause falsely decreased levels.
Hypoglycemia, physical activity, stress, and a variety of drugs (e.g., amphetamines, arginine,
dopamine, levodopa, methyldopa, beta blockers,
histamine, nicotinic acid, estrogens) may cause
falsely elevated levels.38
INDICATIONS FOR GROWTH HORMONE TEST

Growth retardation in children with decreased
levels indicative of pituitary etiology
Monitoring for response to treatment of growth
retardation caused by GH deficiency
Suspected disorder associated with decreased GH
(e.g., pituitary tumors, craniopharyngiomas,
tuberculosis meningitis, and pituitary damage or
trauma)
Gigantism in children with increased levels
indicative of pituitary etiology
Support for diagnosing acromegaly in adults as
indicated by elevated levels; acidophil or chromophobe tumors of the adenohypophysis may
account for these elevated levels39
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
The client should be informed that the test will be
performed on 2 consecutive days, between the
hours of 6 and 8 AM.
The client should fast from food and avoid strenuous exercise for 12 hours before each sample is
drawn.
Additionally, it is recommended by some that the
client be maintained on bed rest for 1 hour before
each sample is obtained.

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Tests

Because many drugs may affect serum GH levels,
a medication history should be obtained. It is
recommended that those drugs that alter test
results be withheld for 12 hours before the study,
although this practice should be confirmed with
the person ordering the test.

Reference Values
Conventional Units

SI Units

Arginine
Men

10 ng/mL

10 g/L

THE PROCEDURE

Women

15 ng/mL

15 g/L

The test is performed on 2 consecutive days, between
the hours of 6 and 8 AM. A venipuncture is
performed and the sample collected in a red-topped
tube. The sample should be handled gently to avoid
hemolysis and sent immediately to the laboratory.

L-Dopa

7 ng/mL above
baseline level

7 g/L

NURSING CARE AFTER THE PROCEDURE

GROWTH HORMONE STIMULATION
TESTS
Baseline levels of GH are affected by many factors
and may be misleading at times. Stimulation tests
are performed to determine responsiveness to
substances that normally stimulate GH secretion,
such as arginine and L-dopa. Insulin also may be
given to induce hypoglycemia, which in turn stimulates GH secretion. It has been found that blood
sugar levels of less than 50 mg/dL cause GH levels to
rise 10 times or more in normal individuals.
Idiosyncratic responses to the different stimulants
may occur. Thus, it may be necessary to perform two
or three different stimulation tests before arriving at
diagnostic conclusions.40
INTERFERING FACTORS

Factors that may affect serum GH determinations
also may alter results of GH stimulation tests.
INDICATIONS FOR GROWTH HORMONE
STIMULATION TESTS

Low or undetectable serum GH levels, with
GH deficiency or adult panhypopituitarism

or insulin

confirmed by no increase after administration of
the stimulant
Confirmation of the diagnosis of acromegaly as
evidenced by reduced GH output after L-dopa is
administered as a stimulant (i.e., an idiosyncratic
response is seen in acromegaly)
Nursing Alert

If insulin is used as the stimulant, the client
should be observed carefully during and after
the test for signs and symptoms of extreme
hypoglycemia.
NURSING CARE BEFORE THE PROCEDURE

Initial client preparation is the same as that for
serum GH determinations.
The client should be weighed on the day of the
test because dosage of the stimulant is determined
by weight.
Because several blood samples will be obtained
and because certain of the stimulants (i.e., insulin
and arginine) are administered IV, the client
should be informed that an intermittent venous
access device (e.g., heparin lock) will be inserted.
THE PROCEDURE

An intermittent venous access device is inserted,
usually at about 8 AM, and a venous sample is
obtained and placed in a red-topped tube. The
sample is handled gently to avoid hemolysis and sent
to the laboratory immediately.
The stimulant is then administered. L-Dopa is
administered orally; arginine and insulin are administered IV in a saline infusion. If insulin is used to
lower blood sugar, an ampule of 50 percent glucose
should be on hand in the event that severe hypoglycemia occurs.
After the stimulant is administered, three blood
samples are obtained via the venous access device at
30-minute intervals. The samples are placed in redtopped tubes and sent to the laboratory immediately
upon collection.

CHAPTER 5—Blood

Chemistry

163

NURSING CARE AFTER THE PROCEDURE

THE PROCEDURE

Care and assessment after the procedure are essentially the same as for serum GH determinations.
If an intermittent venous access device was
inserted for the procedure, remove after completion of the test and apply a pressure bandage to
the site.
If insulin was used as the stimulant, resume
dietary intake as soon as possible after the test is
completed and observe for signs of hypoglycemia.
Complications and precautions: If insulin is
used, note and report signs and symptoms of
hypoglycemia such as sweating, tachycardia,
tremors, irritability, or confusion. Prepare client
for IV glucose administration.

A venipuncture is performed and a sample collected
in a red-topped tube. The sample is handled gently
to avoid hemolysis and sent to the laboratory immediately.
The glucose solution (usually 100 g) is administered orally. If the client is unable to drink or retain
the glucose solution, the physician is notified. IV
glucose may be administered, if necessary, to
perform the test.
After 1 to 2 hours, depending on laboratory
procedures, a second blood sample is collected in a
red-topped tube and sent to the laboratory immediately.

GROWTH HORMONE SUPPRESSION
TEST

Care and assessment after the procedure are the
same as for serum GH determinations.
Complications and precautions: Monitor for
hyperglycemia after ingestion of the glucose solution.

Hyperglycemia suppresses GH secretion in normal
individuals. This principle is used in evaluating individuals with abnormally elevated levels and those
who are believed to be hypersecreting GH but who
show normal levels on routine serum GH determinations. Administration of a glucose load that
produces hyperglycemia should decrease serum GH
levels within 1 to 2 hours. In individuals who are
hypersecreting GH, a decrease in serum GH will not
occur in response to hyperglycemia. Note that the
test may require repetition to confirm results.
Reference Values
Conventional Units
3 ng/dL

SI Units
3 g/L

INTERFERING FACTORS

Factors that may affect serum GH determinations
may also alter results of GH suppression tests.
INDICATIONS FOR GROWTH HORMONE
SUPPRESSION TEST

Elevated serum GH levels
Signs of GH hypersecretion with serum GH levels
within normal limits
Confirmation of GH hypersecretion as indicated
by decreased response to GH suppression
NURSING CARE BEFORE THE PROCEDURE

Initial client preparation is the same as that for
serum GH determinations.
The client should be informed that it will be
necessary to drink an oral glucose solution and
that two blood samples will be obtained.

NURSING CARE AFTER THE PROCEDURE

PROLACTIN
Prolactin (hPRL, LTH) is secreted by the acidophil
cells of the adenohypophysis. It is unique among
hormones in that it responds to inhibition via the
hypothalamus rather than to stimulation; that is,
prolactin is secreted except when influenced by the
hypothalamic inhibiting factor, which is believed to
be the neurotransmitter dopamine.
The only known function of hPRL is to induce
milk production in a female breast already stimulated by high estrogen levels. Once milk production
is established, lactation can continue without
elevated prolactin levels. Levels of hPRL rise late in
pregnancy, peak with the initiation of lactation, and
surge each time a woman breast-feeds. The function
of hPRL in men is not known.
Excessive circulating hPRL disturbs sexual function in both men and women. Women experience
amenorrhea and anovulation, and they may have
inappropriate milk secretion (galactorrhea). Men
experience impotence, which occurs even when
testosterone levels are normal, and sometimes
gynecomastia.41
INTERFERING FACTORS

Therapy with drugs such as estrogens, oral
contraceptives, reserpine, -methyldopa, phenothiazines, haloperidol, tricyclic antidepressants,
and procainamide derivatives may produce
elevated levels.
Episodic elevations may occur in response to
sleep, stress, exercise, and hypoglycemia.

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be handled gently to avoid hemolysis and transported promptly to the laboratory.

Reference Values
Conventional Units

SI Units

Children

1–20 ng/mL

1–20 g/L

Men

1–20 ng/mL

1–20 g/L

Nonlactating

1–25 ng/mL

1–25 g/L

Menopausal

1–20 ng/mL

1–20 g/L

Women

Therapy with dopamine, apomorphine, and ergot
alkaloids may produce decreased levels.

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Complications and precautions: Assess for signs
and symptoms of pituitary conditions such as
mood changes; body image changes; sexual
dysfunction in men; and menstrual, milk secretion, and weight gain abnormalities in women.

ADRENOCORTICOTROPIC HORMONE

INDICATIONS FOR SERUM PROLACTIN TEST

Sexual dysfunction of unknown etiology in men
and women, because excessive circulating hPRL
may indicate the source of the problem (e.g.,
damage to the hypothalamus, pituitary adenoma)
Failure of lactation in the postpartum period or
suspected postpartum hypophyseal infarction
(Sheehan’s syndrome), or both, as indicated by
decreased levels
Suspected tumor involving the lungs or kidneys,
with elevated levels indicating ectopic hPRL
production
Support for diagnosing primary hypothyroidism
as indicated by elevated levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter serum hPRL levels,
a medication history should be obtained. It is
recommended that drugs that may alter test
results be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should

Adrenocorticotropic hormone (ACTH) is secreted
by the basophils of the adenohypophysis. ACTH
stimulates the adrenal cortex to secrete (1) glucocorticoids, of which cortisol predominates; (2) adrenal
androgens, which are converted by the liver to
testosterone; and, to a lesser degree, (3) mineralocorticoids, of which aldosterone predominates.
ACTH secretion is closely linked to melanocytestimulating hormone; it also is thought to stimulate
pancreatic cells and the release of GH.
ACTH release, which is stimulated by its corresponding hypothalamic releasing factor, occurs
episodically in relation to decreased circulating
levels of glucocorticoid, increased stress, and hypoglycemia. ACTH levels also vary diurnally; the highest levels occur on awakening, decrease throughout
the day, and then begin to rise again a few hours
before awakening. Circulating aldosterone levels
may influence ACTH secretion to some extent;
however, androgens are believed to have no effect on
ACTH levels. ACTH assays are expensive to perform
and are not universally available.
INTERFERING FACTORS

ACTH levels vary diurnally; highest levels occur
upon awakening, decrease throughout the day,
and then begin to rise again a few hours before
awakening.

Reference Values
Conventional Units

SI Units

BioScience Laboratories

80 pg/mL at 8 AM

17.6 pmol/L

Mayo Clinic

120 pg/mL at 6 to 8 AM

26.4 pmol/L

Note: Normal values vary according to the laboratory performing the test. Results are
usually evaluated in relation to other tests of adrenal-hypophyseal function (e.g., plasma
cortisol).

CHAPTER 5—Blood

Numerous drugs may lead to decreased ACTH
levels (e.g., adrenocorticosteroids, estrogens,
calcium gluconate, amphetamines, spironolactone, and ethanol).
Stress, exercise, and blood glucose levels may
affect results.
INDICATIONS FOR PLASMA ADRENOCORTICOTROPIC
HORMONE TEST

Signs and symptoms of adrenocortical dysfunction:
Elevated ACTH levels with low cortisol levels
indicate adrenocortical hypoactivity (Addison’s
disease).
Low ACTH levels with high cortisol levels indicate adrenocortical hyperactivity (Cushing’s
syndrome) caused by benign or malignant
adrenal tumors.
High ACTH levels, without diurnal variation,
combined with high cortisol levels indicate
adrenocortical hyperfunction caused by excessive ACTH production (e.g., resulting from
pituitary adenoma and nonendocrine malignant tumors in which there is ectopic ACTH
production).
Decreased ACTH levels are associated with
panhypopituitarism, hypothalamic dysfunction, and long-term adrenocorticosteroid
therapy.
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
study involving the collection of a peripheral blood
sample (see Appendix I).
For this test, the client should follow a low-carbohydrate diet for 48 hours and fast from food for 12
hours before the test.
In addition, strenuous exercise should be avoided
for 12 hours before the test, and 1 hour of bed rest
is necessary immediately before the test.
Medications that may alter test results should be
withheld for at least 24 to 48 hours or longer
before the study, although this practice should be
confirmed with the person ordering the test.
The client should be informed that it may be
necessary to obtain more than one sample and
that samples must be obtained at specific times to
detect peak and trough levels of ACTH.
THE PROCEDURE

Between 6 and 8 AM (peak ACTH secretion time), a
venipuncture is performed and the sample collected
in a green-topped tube. The sample must be placed
in a container of ice and sent to the laboratory
immediately. When ACTH hypersecretion is

Chemistry

165

suspected, a second sample may be obtained
between 8 and 10 PM to determine whether diurnal
variation in ACTH levels is occurring.
The ACTH stimulation test can be conducted by
the timed serial laboratory analysis of blood
plasma samples for cortisol levels after the administration of metyrapone. The ACTH suppression
test can be conducted by the laboratory analysis of
blood plasma samples for cortisol levels after the
administration of dexamethasone. The tests are
performed to assist in the diagnosis of Addison’s
disease or Cushing’s syndrome.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume foods and any medications withheld
before the test, as well as usual activities.
Complications and precautions: Note cortisol
level and its relation to increases in ACTH
production by the pituitary gland.

THYROID-STIMULATING HORMONE
Thyroid-stimulating hormone (TSH) is produced
by the basophil cells of the adenohypophysis in
response to stimulation by its hypothalamic releasing factor, thyrotropin-releasing hormone (TRH).
TRH responds to decreased circulating levels of
thyroid hormones, as well as to intense cold,
psychological tension, and increased metabolic
need, and it stimulates the adenohypophysis to
secrete TSH. TSH accelerates all aspects of hormone
production by the thyroid gland and enhances
hPRL release. Measuring TSH provides useful information about both hypophyseal and thyroid gland
function.
Hypersecretion of TSH by the adenohypophysis
(e.g., because of TSH-secreting pituitary tumors)
causes hyperthyroidism as a result of excessive stimulation of the thyroid gland. Elevated TSH levels are
also seen with prolonged emotional stress and are
more common in colder climates. Primary hypothyroidism (i.e., hypothyroidism caused by disorders
involving the thyroid gland itself) leads to elevated
TSH levels because of normal feedback mechanisms.
TSH levels are normally elevated at birth.
Note that increased TSH secretion is associated
with excess secretion of exophthalmos-producing
substance, which also originates in the adenohypophysis. This substance promotes water storage in
the retro-orbital fat pads and causes the eyes to
protrude, a common sign of hyperthyroidism.
Exophthalmos sometimes persists after the hyper-

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thyroidism is corrected and also may occur in
persons with normal thyroid function.
TSH levels are normal in situations in which the
functional ability of the thyroid gland is normal but
the thyroid hormone levels are low, a phenomenon
that is seen in clients with severe illnesses with
protein deficiency (thyroid hormones are proteins)
such as neoplastic disease, severe burns, trauma,
liver disease, renal failure, and cardiovascular problems. Deficiency of thyroid hormone produces a
hypometabolic state. Excess TSH production is not
stimulated, however, because circulating thyroid
levels are appropriate to the client’s metabolic needs
(i.e., the person is metabolically euthyroid). Treatment involves correcting the underlying causes. The
apparent hypothyroidism is not treated, however,
because such treatment could be devastating to a
severely debilitated person.
TSH is measured by radioimmunoassay.
Immunologic cross-reactivity occurs with glycoprotein hormones such as human chorionic gonadotropin (hCG), follicle-stimulating hormone
(FSH), and luteinizing hormone (LH).
Reference Values
Conventional Units
Newborns
Children and
adults

SI Units

25 IU/mL
by day 3

25 mU/L

10 IU/mL

10 mU/L

INTERFERING FACTORS

Aspirin, adrenocorticosteroids, and heparin may
produce decreased TSH levels.
Lithium carbonate and potassium iodide may
produce elevated TSH levels.
Falsely increased levels may occur in hydatidiform
mole, choriocarcinoma, embryonal carcinoma of
the testes, pregnancy, and postmenopausal states
characterized by high FSH and LH levels.42
INDICATIONS FOR THYROID-STIMULATING
HORMONE TEST

Signs and symptoms of hypothyroidism, hyperthyroidism, or suspected pituitary or hypothalamic dysfunction, or hypothyroidism or
hyperthyroidism combined with suspected pituitary or hypothalamic dysfunction:
Elevated levels are seen with primary hypothyroidism.
Decreased or undetectable levels are associated
with secondary hypothyroidism caused by
pituitary or hypothalamic hypofunction.

Decreased levels are seen with primary hyperthyroidism.
Elevated levels may indicate secondary hyperthyroidism resulting from pituitary hyperactivity (e.g., caused by tumor).
Differentiation of functional euthyroidism from
true hypothyroidism in debilitated individuals,
with the former indicated by normal levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving collection of a peripheral blood sample
(see Appendix I).
It is recommended that drugs known to alter TSH
levels be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample is
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.
The test for TSH is used on newborns to screen
for congenital hypothyroidism. It is performed by
obtaining a sample of blood from a heelstick and
saturating a spot on a special filter paper with the
blood. A kit is available for this test; it contains a
comparison chart to identify elevations.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Complications and precautions: Note the relation of TSH to levels of other thyroid tests indicating hypothyroidism as opposed to other
thyroid disorders.

TSH STIMULATION TEST
The TSH stimulation test is used to evaluate the
thyroid–pituitary–hypothalamic feedback loop. In
this test, a purified form of hypothalamic
thyrotropin-releasing hormone (TRH) is administered IV. Normally, TRH stimulates the adenohypophysis to release TSH, which, in turn, causes
hormonal release from the thyroid gland. A normal
response (e.g., elevated TSH levels) indicates that the
adenohypophysis is capable of responding to TRH
stimulation. If thyroid hormones also are measured
as part of the test, elevated levels indicate that the
thyroid gland is capable of responding to TSH stimulation.

CHAPTER 5—Blood

Reference Values
TSH levels rise within 15 to 30 minutes of TRH
administration, peak at 2.5 to 4 times normal,
and return to baseline levels within 2 to 4 hours.
Thyroid hormone secretion (e.g., T3 and T4),
which should be increased by 50 to 75 percent,
occurs in 1 to 4 hours.
INDICATIONS FOR TSH STIMULATION TEST

Low or undetectable serum TSH levels, hypothyroidism, or hyperthyroidism of unknown etiology
or type, or low serum TSH levels combined with
hypothyroidism or hyperthyroidism:
A normal or delayed TSH response in persons
with low baseline TSH levels and signs of
hypothyroidism indicates hypothalamic
dysfunction or disruption of the hypothalamic–hypophyseal portal circulation and
confirms the diagnosis of tertiary hypothyroidism.
A decreased or absent TSH response in persons
with low baseline TSH levels and signs of
hypothyroidism indicates hypopituitarism and
confirms the diagnosis of secondary hypothyroidism.
A normal or increased TSH response in clients
with elevated baseline TSH levels and signs of
hypothyroidism, with persistently decreased
thyroid gland hormone levels, confirms the
diagnosis of primary hypothyroidism.
A decreased or absent TSH response in persons
with low baseline TSH levels and signs of
hyperthyroidism, with persistently elevated
thyroid gland hormone levels, indicates that
thyroid hormone production is occurring
autonomously and confirms the diagnosis of
primary hyperthyroidism.
NURSING CARE BEFORE THE PROCEDURE

Initial client preparation is the same as that for
serum determinations of TSH.
Because several blood samples will be obtained
and because the TRH will be administered IV, the
client should be informed that an intermittent
venous access device (e.g., heparin lock) may be
inserted.
THE PROCEDURE

The procedure varies somewhat according to the
laboratory performing the test. One example of the
procedure is described subsequently.
An intermittent venous access device is inserted
and a venous sample is obtained and placed in a red-

Chemistry

167

topped tube. The sample is handled gently to avoid
hemolysis and sent promptly to the laboratory. The
sample should be labeled either with the time drawn
or as the baseline sample.
A bolus of TRH is then administered IV through
the access device. Additional blood samples are
obtained via the access device 1/2, 1, 2, 3, and 4 hours
after administration of the TRH. Each sample is
placed in a red-topped tube, labeled, and sent to the
laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are essentially the same as for serum TSH determinations.
If an intermittent venous access device was
inserted for the procedure, remove after completion of the test and apply a pressure bandage to
the site.
Complications and precautions: Note increased
levels in relation to other thyroid tests and prepare
client for a nuclear scan laboratory study using
the iodine 131 (131I) radionuclide (see Chapter
20).

FOLLICLE-STIMULATING HORMONE
Follicle-stimulating hormone (FSH) is secreted by
the basophil cells of the adenohypophysis in
response to stimulation by hypothalamic gonadotropin-releasing hormone (GnRH), which also is
called luteinizing hormone–releasing hormone
(LHRH) and follicle-stimulating hormone–releasing factor. FSH affects gonadal function in both men
and women. In women, FSH promotes maturation
of the graafian (germinal) follicle, causing estrogen
secretion and allowing the ovum to mature. In men,
FSH partially controls spermatogenesis, but the
presence of testosterone also is necessary. GnRH
secretion, which in turn stimulates FSH secretion, is
stimulated by decreased estrogen and testosterone
levels. Isolated FSH elevation also may occur when
there is failure to produce spermatozoa, even though
testosterone production is normal. FSH production
is inhibited by rising estrogen and testosterone
levels.
FSH levels are normally low during childhood
but begin to rise as puberty approaches. Surges of
FSH occur initially during sleep but, as puberty
advances, daytime levels also rise. During childbearing years, FSH levels in women vary according
to the menstrual cycle. Decreased FSH levels after
puberty are associated with male and female infertility. After the reproductive years, estrogen and testosterone levels decline, causing FSH levels to rise in
response to normal feedback mechanisms. A 24-

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hour urine specimen also can be collected and tested
for FSH.

FSH/LH CHALLENGE TESTS
The hypothalamic–hypophyseal–gonadal axis can be
evaluated by administering drugs and hormones
known to affect specific hormonal interactions.
These include clomiphene, GnRH, hCG, and progesterone.
Clomiphene, a drug used to treat infertility,
prevents the hypothalamus from recognizing
normally inhibitory levels of estrogen and testosterone. Consequently, the hypothalamus continues
to secrete GnRH, which, in turn, continues to stimulate the adenohypophysis to secrete FSH and LH.
After 5 days of clomiphene, both FSH and LH levels
rise, usually 50 to 100 percent above baseline levels.
In anovulatory women whose ovaries are normal,
clomiphene often enhances FSH and LH levels so
that ovulation is induced. If FSH and LH levels do
not rise with clomiphene administration, either
hypothalamic or hypophyseal dysfunction is indicated. The source of the dysfunction may be identified by administering purified GnRH. If FSH and
LH levels rise, the pituitary gland is normal but
hypothalamic function is impaired. FSH and LH
levels that do not rise indicate hypophyseal dysfunction.
Human chorionic gonadotropin (hCG), a placental hormone with effects similar to those of LH, is
used to evaluate testicular activity in men with low
testosterone levels. Elevated testosterone levels after
hCG administration indicate that testicular function
is normal but that hypothalamic–pituitary activity is
impaired. Failure of testosterone levels to rise
suggests primary testicular dysfunction.

Progesterone, a hormone secreted by the ovary, is
used to evaluate amenorrhea. In the normal
menstrual cycle, the progesterone surge that follows
ovulation inhibits GnRH secretion, and hormonal
levels decline. Menstrual bleeding, also called withdrawal bleeding, occurs when the estrogen-stimulated endometrium experiences a drop in hormonal
stimulation. This normal situation can be simulated
by administering oral or IM progesterone to amenorrheic women already exposed to adequate estrogen levels. If menstrual bleeding occurs, the
underlying cause of the amenorrhea is failure to
ovulate. Lack of bleeding in response to progesterone administration indicates (1) inadequate
estrogen production, resulting from either primary
ovarian failure or inadequate pituitary secretion of
FSH; (2) hypothalamic dysfunction with defective
GnRH secretion; (3) impaired hypophyseal response
to GnRH; or (4) abnormal uterine response to
hormonal stimulation. These possibilities can be
distinguished by administering estrogen to stimulate
the endometrium and then repeating the progesterone challenge. If bleeding occurs, then either
ovarian failure or inadequately responsive hypothalamic–hypophyseal activity is the underlying cause of
the amenorrhea. Measuring FSH, LH, and estrogen
levels helps further to diagnose the problem.43
INTERFERING FACTORS

In menstruating women, values vary in relation to
the phase of the menstrual cycle.
Values are higher in postmenopausal women.
Administration of the drug clomiphene may
result in elevated FSH levels.
Therapy with estrogens, progesterone, and
phenothiazines may result in decreased FSH
levels.44

Reference Values
Conventional Units

SI Units

Children

5–10 mIU/mL

5–10 IU/L

Men

10–15 mIU/mL

10–15 IU/L

Early in cycle

5–25 mIU/mL

5–25 IU/L

Midcycle

20–30 mIU/mL

20–30 IU/L

Luteal phase

5–25 mIU/mL

5–25 IU/L

Women (menopausal)

40–250 mIU/mL

40–250 IU/L

Women (menstruating)

Note: Results should be evaluated in relation to other tests of gonadal function.

CHAPTER 5—Blood

INDICATIONS FOR FOLLICLE-STIMULATING
HORMONE TEST

Evaluation of ambiguous sexual differentiation in
infants
Evaluation of early sexual development in girls
under age 9 years or boys under age 10 years, with
precocious puberty associated with elevated levels
Evaluation of failure of sexual maturation in
adolescence
Evaluation of sexual dysfunction or changes in
secondary sexual characteristics in men and
women:
Elevated levels are associated with ovarian or
testicular failure, with polycystic ovary disease,
after viral orchitis, and with Turner’s syndrome
in women and Klinefelter’s syndrome in men.
Decreased levels may be seen with neoplasms
of the testes, ovaries, and adrenal glands, resulting in excessive production of sex hormones.
Suspected pituitary or hypothalamic dysfunction:
Elevated levels may be seen in pituitary tumors.
Decreased levels are associated with hypothalamic lesions and panhypopituitarism.
Suspected early acromegaly as indicated by
elevated levels
Suspected disorders associated with decreased
FSH levels, such as anorexia nervosa and renal
disease
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
It is recommended that drugs known to alter FSH
levels be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.
In women, the phase of the menstrual cycle
should be ascertained, if possible.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported to the laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Complications and precautions: Note levels in
relation to 24-hour urinary FSH and LH results.
Prepare client for serial samples for testing.

Chemistry

169

LUTEINIZING HORMONE
Luteinizing hormone is secreted by the basophil cells
of the adenohypophysis in response to stimulation
by GnRH, the same hypothalamic releasing factor
that stimulates FSH release. LH affects gonadal function in both men and women. In women, a surge of
LH occurs at the midpoint of the menstrual cycle
and is believed to be induced by high estrogen levels.
LH causes the ovum to be expelled from the ovary
and stimulates development of the corpus luteum
and production of progesterone. As progesterone
levels rise, LH production decreases. In men, LH
stimulates the interstitial Leydig cells, located in the
testes, to produce testosterone.
During childhood, LH levels decrease and are
lower than those of FSH. Similarly, LH levels rise
after those of FSH as puberty approaches. During the
childbearing years, LH levels in women vary according to the menstrual cycle but remain fairly constant
in men. Decreased LH levels after puberty are associated with male and female infertility. After the reproductive years, as gonadal hormones decline, LH
levels rise in response to normal feedback mechanisms. The rise in LH levels, however, is not as
marked as that for FSH levels. A 24-hour urine specimen also can be collected and tested for LH.
INTERFERING FACTORS

In menstruating women, values vary in relation to
the phase of the menstrual cycle.
Values are higher in postmenopausal women.
Drugs containing estrogen tend to cause elevated
LH levels.
Drugs containing progesterone and testosterone
may lead to decreased levels.
INDICATIONS FOR SERUM LUTEINIZING
HORMONE TEST

Evaluation of male and female infertility, as indicated by decreased levels
Support for diagnosing infertility caused by
anovulation as evidenced by lack of the midcycle
LH surge
Evaluation of response to therapy to induce
ovulation
Suspected pituitary or hypothalamic dysfunction:
Elevated levels may be seen in pituitary tumors.
Decreased levels are associated with hypothalamic lesions and panhypopituitarism.
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).

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Tests

Reference Values
Conventional Units

SI Units

Children

5–10 mIU/mL

5–10 IU/L

Men

5–20 mIU/mL

5–20 IU/L

Early in cycle

5–25 mIU/mL

5–25 IU/L

Midcycle

40–80 mIU/mL

40–80 IU/L

Luteal phase

5–25 mIU/mL

5–25 IU/L

Women (menopausal)

75 mIU/mL

75 IU/L

Women (menstruating)

Note: Results should be evaluated in relation to other tests of gonadal function.

It is recommended that any drugs known to alter
LH levels be withheld for 12 to 24 hours before
the test, although this practice should be
confirmed with the person ordering the study.
In women, the phase of the menstrual cycle
should be ascertained, if possible.
If the test is being performed to detect ovulation,
the client should be informed that it may be
necessary to obtain a series of samples over a
period of several days to detect peak LH levels.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.

Psychogenic stimuli (e.g., stress, pain, anxiety) also
may stimulate ADH release, but the mechanism by
which this occurs is unclear.
ADH acts on the epithelial cells of the distal
convoluted tubules and the collecting ducts of the
kidneys, making them permeable to water. Thus,
with ADH, more water is absorbed from the
glomerular filtrate into the bloodstream. Without
ADH, water remains in the filtrate and is excreted,
producing very dilute urine. In contrast, maximal
ADH secretion produces very concentrated urine.
ADH also is believed to stimulate mild contractions
in the pregnant uterus and to aid in promoting milk
ejection in lactation, functions similar to those of
oxytocin, which also is secreted by the hypothalamus
and released by the neurohypophysis.

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Abnormal test results, complications, and
precautions: Respond as for FSH testing, because
LH is usually performed on the same blood
sample.

ANTIDIURETIC HORMONE
Antidiuretic hormone (ADH) is formed by the
hypothalamus but is stored in the neurohypophysis
(posterior pituitary gland). ADH is released in
response to increased serum osmolality or decreased
blood volume. Although as little as a 1 percent
change in serum osmolality will stimulate ADH
secretion, blood volume must decrease by approximately 10 percent for ADH secretion to be induced.

Reference Values
Conventional Units
2.3–3.1 pg/mL

SI Units
2.3–3.1 ng/L

INTERFERING FACTORS

Alcohol, phenytoin drugs, -adrenergic drugs,
and morphine antagonists may lead to decreased
ADH secretion.
Acetaminophen, barbiturates, cholinergic agents,
clofibrate, estrogens, nicotine, oral hypoglycemic
agents, cytotoxic agents (e.g., vincristine), tricyclic
antidepressants,
oxytocin,
carbamazepine
(Tegretol), and thiazide diuretics may lead to
increased ADH secretion.45
Pain, stress, and anxiety may lead to increased
ADH secretion.
Failure to follow dietary and exercise restrictions
before the test may alter results.

CHAPTER 5—Blood

INDICATIONS FOR SERUM ANTIDIURETIC
HORMONE TEST

Polyuria or altered serum osmolality of unknown
etiology, or both, to identify possible alterations in
ADH secretion as the cause
Central nervous system trauma, surgery, or
disease that may lead to impaired secretion of
ADH
Differentiation of neurogenic (central) diabetes
insipidus from nephrogenic diabetes insipidus:
Neurogenic diabetes insipidus is characterized
by decreased ADH levels.
ADH levels may be elevated in nephrogenic
diabetes insipidus if normal feedback mechanisms are intact.
Known or suspected malignancy associated with
syndrome of inappropriate ADH (SIADH) secretion (e.g., oat cell lung cancer, thymoma,
lymphoma, leukemia, and carcinoma of the
pancreas, prostate gland, and intestine), with the
disorder indicated by elevated ADH levels
Known or suspected pulmonary conditions associated with SIADH secretion (e.g., tuberculosis,
pneumonia, and positive pressure mechanical
ventilation), with the disorder indicated by
elevated ADH levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving collection of a peripheral blood
sample (see Appendix I).
The client should fast from food and avoid strenuous exercise for 12 hours before the sample is
obtained. It is recommended that drugs that may
alter ADH levels be withheld for 12 to 24 hours
before the study, although this practice should be
confirmed with the person ordering the test.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a plastic red-topped tube. Plastic is used
because contact with glass causes degradation of
ADH. The sample should be handled gently to avoid
hemolysis and sent to the laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving collection of a
peripheral blood sample.
Resume food and any medications withheld
before the test, as well as usual activities.
Abnormal levels: Note and report increased levels
in relation to renin level. Assess for fluid volume
excess resulting from sodium and water retention.

Chemistry

171

Monitor I&O, weight gain, edema, and increases
in blood pressure. Instruct in diuretic therapy
regimen. Note and report decreased levels in relation to sodium level. Assess for fluid volume
deficit. Monitor I&O and weight loss. Instruct in
long-term fluid, sodium, and corticosteroid therapy regimen.

Thyroid and Parathyroid
Hormones
The thyroid gland synthesizes and releases thyroxine
(T4) and triiodothyronine (T3) in response to stimulation by TSH, which is secreted by the adenohypophysis. The thyroid gland synthesizes its
hormones from iodine and the essential amino acid
tyrosine. Most of the body’s iodine is ingested as
iodide through dietary intake and is absorbed into
the bloodstream from the gastrointestinal tract.
One-third of the absorbed iodide enters the thyroid
gland; the remaining two-thirds is excreted in the
urine. In the thyroid gland, enzymes oxidize iodide
to iodine.
The thyroid gland secretes a protein, thyroglobulin, into its follicles. Thyroglobulin has special properties that allow the tyrosine contained in its
molecules to react with iodine to form thyroid
hormones. The thyroid hormones thus formed are
stored in the follicles of the gland as the thyroglobulin–thyroid hormone complex called colloid.
When thyroid hormones are released into the
bloodstream, they are split from thyroglobulin as a
result of the action of proteases, which are secreted
by thyroid cells in response to stimulation by TSH.
Much more T4 than T3 is secreted into the bloodstream. Upon entering the bloodstream, both immediately combine with plasma proteins, mainly
thyroxine-binding globulin (TBG), but also with
albumin and prealbumin. Although more than 99
percent of both T4 and T3 are bound to TBG, physiological activity of both hormones results from only
the unbound (“free”) molecules. Note also that TBG
has greater affinity for T4 than for T3, which allows
for more rapid release of T3 from TBG for entry into
body cells. T3 is thought to exert at least 65 to 75
percent of thyroidal hormone effects, and it is
believed by some that T4 has no endocrine activity at
all until it is converted to T3, which occurs when one
iodine molecule is removed from T4.46
The main function of thyroid hormones is to
increase the metabolic activities of most tissues by
increasing the oxidative enzymes in the cells. This
increase, in turn, causes increased oxygen consumption and increased utilization of carbohydrates,

172

SECTION I—Laboratory

Tests

proteins, fats, and vitamins. Thyroid hormones also
mobilize electrolytes and are necessary for the
conversion of carotene to vitamin A. Although the
mechanism is not known, thyroid hormones are
essential for the development of the central nervous
system. Thyroid-deficient infants may suffer irreversible brain damage (cretinism). Thyroid deficiency in adults (myxedema) produces diffuse
psychomotor retardation, which is reversible with
hormone replacement. Thyroid hormones also are
thought to increase the rate of parathyroid hormone
secretion.
Alterations in thyroid hormone production may
be caused by disorders affecting the hypothalamus,
which secretes thyrotropin-releasing hormone in
response to circulating T4 and T3 levels; the pituitary
gland; or the thyroid gland itself. Such alterations
may affect all body systems. Hypothyroidism is the
general term for the hypometabolic state induced by
deficient thyroid hormone secretion, whereas hyperthyroidism indicates excessive production of thyroid
hormones.
An additional hormone produced by the thyroid
gland is calcitonin, which is secreted in response to
high serum calcium levels. Calcitonin causes an
increase in calcium reabsorption by bone, thus
lowering serum calcium.47
A number of tests pertaining to thyroid hormones
may be performed, some of which may be grouped
as a “thyroid screen” (e.g., T4, T3, and TSH). A “T7”
is sometimes ordered. This is interpreted as a T4 plus
a T3, because there is no such substance as T7. Before
it was possible to measure thyroid hormones
directly, serum iodine measurements (e.g., proteinbound iodine) were used as indicators of thyroid
function. These tests were severely affected by
organic and inorganic iodine contaminants and are
no longer used to any great extent. Similarly, measurement of thyroidal uptake of radioactive iodine
(131I) has been replaced by direct measurements of
T4 and TSH.48

THYROXINE
Thyroxine (T4) is measured by competitive protein
binding or by radioimmunoassay. In competitive
protein binding, the affinity between T4 and TBG is
exploited. Reagent TBG fully saturated with radiolabeled T4 is incubated with T4 extracted from the
client’s serum. TheT4 from the test serum displaces
the radiolabeled T4 in the amount present. This
procedure is known as T4 by displacement (T4 D), T4
by competitive binding (T4 CPB), and T4 MurphyPattee (T4 MP). T4 measured by radioimmunoassay
(T4 RIA) is the preferred method to measure T4

because it is not affected by circulating iodinated
substances.
Most T4 (99.97 percent) in the serum is bound to
TBG. The remainder circulates as unbound (“free”)
T4 (FT4) and is responsible for all of the physiological activity of thyroxine. Because FT4 is not dependent on normal levels of TBG, as is the case with total
serum thyroxine, FT4 levels are considered the most
accurate indicator of thyroxine and its thyrometabolic activity. It is difficult, however, to measure FT4
directly because quantities are so small and the
interference from bound T4 is great. Free hormone
levels are, therefore, usually calculated by multiplying the values for total T4 by the T3 uptake ratio. The
result is expressed as the free thyroxine index (FT4 I).
The free hormone index varies directly with the
amount of circulating hormone and inversely with
the amount of unsaturated TBG present in the
serum.49
Reference Values
Conventional Units

SI Units

T4 D
Newborns 11.0–23.0 g/dL

140–230 nmol/L

1–4 mo

7.5–16.5 g/dL

95–200 nmol/L

4–12 mo

5.5–14.5 g/dL

70–185 nmol/L

Children

5.0–13.5 g/dL

65–170 nmol/L

Adults

4.5–13.0 g/dL

60–165 nmol/L

T4 RIA

4.0–12.0 g/dL

50–150 nmol/L

FT4

0.9–2.3 ng/dL

10–30 nmol/L

Note: Values may vary according to the laboratory performing the test. Results should be evaluated in relation to
other tests of thyroid function.
INTERFERING FACTORS

Results of T4 D may be altered by circulating iodinated substances; T4 RIA is not similarly affected.
Pregnancy, estrogen therapy, or estrogen-secreting tumors may produce elevated T4 levels.
Ingestion of thyroxine will elevate T4 levels.
Heroin and methadone may produce elevated T4
levels.
Androgens, glucocorticoids, heparin, salicylates,
phenytoin anticonvulsants, sulfonamides, and
antithyroid drugs such as propylthiouracil may
lead to decreased T4 levels.
INDICATIONS FOR THYROXINE TEST

Signs of hypothyroidism, hyperthyroidism, or
neonatal screening for congenital hypothyroidism

CHAPTER 5—Blood

(required in many states), or hypothyroidism
or hyperthyroidism combined with neonatal
screening:
Decreased T4 and FT4 levels indicate hypothyroid states and also may be seen in early
thyroiditis.
Elevated T4 and FT4 levels indicate hyperthyroid states.
Normal T4 and FT4 levels in clients with signs
of hyperthyroidism may indicate T3 thyrotoxicosis.
Normal FT4 levels are seen in pregnancy,
whereas T4 and TBG are usually elevated.
Monitoring of response to therapy for hypothyroidism or hyperthyroidism:
Elevated T4 and FT4 levels indicate response to
treatment for hypothyroidism.
Decreased T4 and FT4 levels indicate response
to treatment for hyperthyroidism.
Evaluation of thyroid response to protein deficiency associated with severe illnesses (e.g.,
metastatic cancer, liver disease, renal disease,
diabetes mellitus, cardiovascular disorders, burns,
and trauma):
T4 is decreased in such disorders because of a
deficiency of TBG, a protein.
FT4 index is normal, if thyroid function is
normal, because FT4 index is not dependent on
TBG levels.

Chemistry

173

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Increased levels: Note and report increased levels
and relation to other thyroid tests and procedures
performed. Assess for signs and symptoms of
hyperthyroidism such as tachycardia, increased
appetite, diaphoresis, elevated temperature,
exophthalmos, weight loss, insomnia, hyperactivity, or inability to handle stress. Prepare for possible radionuclide therapy or surgical intervention.
Administer ordered medications to reduce levels.
Instruct in adequate fluid and nutritional dietary
intake and eye care for exophthalmos. Instruct
client to avoid stressful situations.
Decreased levels: Note and report decreased
levels and relation to other thyroid tests and
proce-dures. Assess for cold intolerance, weight
gain, skin changes, constipation, lethargy, or
fatigue. Administer ordered replacement therapy.
Instruct client in appropriate fluid and low caloric
nutritional dietary intake, long-term thyroid
medication regimen, control of environment
for relaxation and warmth, and care of skin and
hair. Instruct client to avoid sedatives to promote
sleep.

NURSING CARE BEFORE THE PROCEDURE

TRIIODOTHYRONINE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
It is usually recommended that thyroid medications be withheld for 1 month before the test and
that other drugs that may alter thyroxine levels be
withheld for at least 24 hours before the study.
This practice should be confirmed, however, with
the person ordering the test.
For infants, explain to the parent(s) the purpose
of the test and that it may require repetition in 3
to 6 weeks because of normal changes in infant
thyroid hormone levels.

Although produced in smaller quantities than T4,
triiodothyronine (T3) is physiologically more significant. The competitive protein-binding techniques
that are useful in measuring T4 are not used to measure T3 because it is present in smaller amounts and
has less affinity for TBG than for T4. Thus, T3 is
measured only by radioimmunoassay (T3 RIA).
As with T4, most T3 (99.7 percent) in the serum is
bound to TBG. The remainder circulates as
unbound (“free”) T3 (FT3) and is responsible for all
of the physiological activity of T3. Because FT3 is not
dependent on normal levels of TBG, as is the case
with total T3, FT3 levels are the most accurate indicators of thyrometabolic activity. FT3 levels may be
calculated by multiplying total T3 levels by the T3
uptake ratio.

THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.
For neonatal screening, the sample is obtained by
heelstick. A multiple neonatal screening kit is
usually used; the directions provided with the kit
must be followed carefully.

INDICATIONS FOR TRIIODOTHYRONINE TEST

Support for diagnosing hyperthyroidism in
clients with normal T4 levels, with early hyperthyroidism and T3 thyrotoxicosis indicated by
elevated T3 levels in the presence of normal T4
levels

174

SECTION I—Laboratory

Tests

Reference Values
Conventional Units

SI Units

T3 RIA
Newborns

90–170 ng/dL

1.3–2.6 nmol/L

Adults

80–200 ng/dL

1.2–3.0 nmol/L

FT3

0.2–0.6 ng/dL

0.003–0.009 nmol/L

Reverse triiodothyronine (rT3)

38–44 ng/dL

0.58–0.67 nmol/L

Support for diagnosing “euthyroid sick”
syndrome in severely ill clients with protein deficiency, as indicated by low T3 levels, normal FT3
levels, and elevated rT3 levels50

the RT3 U level determined from a pool of normal
serum
Reference Values
Conventional Units

SI Units

T3 resin uptake

25–35%

0.25–0.35

T3 uptake ratio

0.1–1.35

0.1–0.35

NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving collection of a peripheral blood
sample (see Appendix I).
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

T3 UPTAKE
The T3 uptake (RT3 U) test evaluates the quantity of
TBG in the serum and the quantity of thyroxine (T4)
bound to it. In the T3 uptake procedure, a known
amount of resin containing radiolabeled T3 is added
to a sample of the client’s serum. Normally, TBG in
the serum is not fully saturated with thyroid
hormones; the saturation level varies in relation to
the amounts of TBG and thyroid hormones present.
In the T3 uptake test, the radiolabeled T3 binds with
available TBG sites. Results of the test are determined by measuring the percentage of labeled T3
that remains bound to the resin after all available
sites on TBG have been filled. Note that the percentage of T3 bound to the resin is inversely proportional
to the percentage of TBG saturation in the serum.
Results of the T3 uptake test are evaluated in relation to serum levels of total T4 and T3 and also are
used in calculating FT3 and FT4 indices. For these
calculations, the T3 uptake ratio (RT3 UR) is used, a
ratio obtained by dividing the client’s RT3 U level by

INTERFERING FACTORS

Drugs that alter TBG levels or that compete for
TBG-binding sites may affect test results.
Estrogens may lead to increased TBG levels.
Androgens and glucocorticoids may lead to
decreased TBG levels.
Salicylates and phenytoin anticonvulsants
compete with T4 for TBG-binding sites.
Results may vary during pregnancy when TBG
levels are usually elevated.
INDICATIONS FOR T3 UPTAKE TEST

Signs of hypothyroidism or hyperthyroidism:
Decreased levels (indicating a low percentage of
radiolabeled T3 remaining) indicate low serum
T4 levels and hypothyroidism.
Elevated levels (indicating a high percentage of
radiolabeled T3 remaining) indicate high
serum T4 levels and hyperthyroidism.
Known or suspected problems associated with
altered TBG levels (e.g., hereditary abnormality of
TBG synthesis, drug therapy, pregnancy, and
disorders associated with decreased serum
proteins):
Elevated levels may indicate low TBG levels.
Decreased levels may indicate elevated TBG
levels.
Monitoring for response to therapy with drugs
that compete with T4 for TBG-binding sites:
Elevated levels may indicate that TBG-binding
sites are saturated with competing drugs.
Calculation of free T3 and T4 indices

CHAPTER 5—Blood

NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
It is recommended that drugs that alter TBG
levels or compete for TBG-binding sites be withheld for 12 to 24 hours before the test, although
this practice should be confirmed with the person
ordering the study.
THE PROCEDURE

Chemistry

Diagnosis of hereditary abnormality of globulin
synthesis, indicated by decreased levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
It is recommended that drugs that may alter TBG
levels be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the
test.

NURSING CARE AFTER THE PROCEDURE

THYROXINE-BINDING GLOBULIN

THYROID-STIMULATING
IMMUNOGLOBULINS

Thyroxine-binding globulin (TBG) may be measured directly by radioimmunoassay. Estrogens
elevate serum TBG levels; thus, women who are
pregnant, who are receiving estrogen therapy or oral
contraceptives, or who have estrogen-secreting
tumors have higher TBG levels.
Reference Values
Conventional Units
16–32 g/dL

SI Units
120–180 mg/mL

INTERFERING FACTORS

Estrogens elevate serum TBG levels and, thus,
women who are pregnant, who are receiving
estrogen therapy or oral contraceptives, or who
have estrogen-secreting tumors have higher TBG
levels.
Androgens and corticosteriods decrease serum
TBG levels.
INDICATIONS FOR THYROXINE-BINDING
GLOBULIN TEST

Signs and symptoms of hypothyroidism or hyperthyroidism in conditions associated with altered
TBG levels (e.g., pregnancy), to differentiate true
thyroid disorders from problems related to altered
TBG levels

175

Care and assessment after the procedure are the
same as for any study involving collection of a
peripheral blood sample.
Resume any medications withheld before the test.

The globulin formerly known as long-acting thyroid
stimulator (LATS) is one of the biologically unique
autoantibodies with the effect of stimulating the
target cell. Now called thyroid-stimulating
immunoglobulins (TSI, TSIg), these antibodies react
with the cell surface receptor that usually combines
with TSH. The TSI reacts with the receptors, activates intracellular enzymes, and promotes epithelial
cell activity that operates outside the feedback regulation for TSH.
Reference Values
TSI is not normally detected in the serum,
although it may be found in the serum of about
5 percent of people without apparent hyperthyroidism or exophthalmos.
INTERFERING FACTORS

Administration of radioactive iodine preparations
within 24 hours of the test may alter results.
INDICATIONS FOR THYROID-STIMULATING
IMMUNOGLOBULINS TEST

Known or suspected thyrotoxicosis with elevated
levels found in 50 to 80 percent of affected individuals

176

SECTION I—Laboratory

Tests

Determination of possible etiology of exophthalmos as indicated by elevated levels
Monitoring of response to treatment for thyrotoxicosis with possible relapse indicated by
elevated levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
The client should not have received any radioactive iodine preparations within 24 hours of the
test.
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

CALCITONIN
Calcitonin, also called thyrocalcitonin, is secreted by
the parafollicular or C cells of the thyroid gland in
response to elevated serum calcium levels. Its role is
not completely understood, but the following functions are known: (1) It antagonizes the effects of
parathyroid hormone and vitamin D, (2) it inhibits
osteoclasts that reabsorb bone so that calcium
continues to be laid down and not reabsorbed into
the blood, and (3) it increases renal clearance of
magnesium and inhibits tubular reabsorption of
phosphates. The net result is that calcitonin
decreases serum calcium levels.

tonin levels, when serum calcium levels are
normal. (Further verification may require raising
the serum calcium level by IV infusion of calcium
or pentagastrin and measuring the level to which
plasma calcitonin rises in response; a rise of 0.105
to 0.11 ng/mL is to be expected.)
Altered serum calcium levels of unknown etiology
may be caused by a disorder associated with
altered calcitonin levels.
Elevated calcitonin levels are seen in cancers
involving the breast, lung, and pancreas as a result
of ectopic calcitonin production by tumor cells.
Elevated calcitonin levels also are seen in primary
hyperparathyroidism and in secondary hyperparathyroidism resulting from chronic renal failure.
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving the collection of a peripheral
blood sample (see Appendix I).
For this test, the client should fast from food for at
least 8 hours before collection of the sample.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a green-topped tube. The sample should
be handled gently to avoid hemolysis and transported promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving collection of a
peripheral blood sample.
Resume foods withheld before the test.
Complications and precautions: Note increased
levels. Assess in relation to calcium and parathyroid hormone levels. Prepare the client for subsequent treatment decisions (medication protocol,
surgery).

Reference Values
Conventional Units

SI Units

Men

0.155 ng/mL

0.155 g/L

Women

0.105 ng/mL

0.105 g/L

INTERFERING FACTORS

Failure to fast from food for 8 hours before the
test may alter results.
INDICATIONS FOR CALCITONIN TEST

Support for diagnosing medullary carcinoma of
the thyroid gland is indicated by elevated calci-

PARATHYROID HORMONE
Parathyroid hormone (PTH, parathormone) is
secreted by the parathyroid glands in response to
decreased levels of circulating calcium. Actions of
PTH include (1) mobilizing calcium from bone into
the bloodstream, along with phosphates and protein
matrix; (2) promoting renal tubular reabsorption of
calcium and depression of phosphate reabsorption,
thereby reducing calcium excretion and increasing
phosphate excretion by the kidneys; (3) decreasing
renal secretion of hydrogen ions, which leads to
increased renal excretion of bicarbonate and chloride; and (4) enhancing renal production of active

CHAPTER 5—Blood

Chemistry

177

vitamin D metabolites, causing increased calcium
absorption in the small intestine. The net result of
PTH action is maintenance of adequate serum
calcium levels.

calcium also may be obtained. The sample(s) should
be handled gently to avoid hemolysis and transported promptly to the laboratory.

Reference Values

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume foods withheld before the test.
Increased levels: Note and report increased levels
in relation to calcium and phosphate levels. Assess
for signs and symptoms of hypercalcemia (greater
than 10.5 mg/dL) leading to renal calculi formation, susceptibility to fractures, sluggishness,
lethargy, anorexia, and constipation. Instruct in
dietary restriction of calcium, medication regimen (corticosteroids, antineoplastics, phosphates), or signs and symptoms of hypophosphatemia (less than 3 mg/dL) such as irritability, confusion, and functional deficits.
Instruct in dietary intake of foods rich in phosphorus and medication replacement regimen.
Decreased levels: Note and report decreased levels
in relation to calcium levels. Assess for signs and
symptoms of hypocalcemia (less than 8.5 mg/dL),
such as muscle cramping and spasms of hands and
feet. In mild cases, instruct in dietary intake of
calcium and vitamin D supplements; in severe
states, prepare for IV administration of calcium.

Conventional Units
2.3–2.8 pmol/L

SI Units
23–28 g/mL

Note: PTH is measured by radioimmunoassay. Because the
antibody used for the assay directly affects the results,
values vary according to the laboratory performing the
test.

INTERFERING FACTORS

Failure to fast from food for 8 hours before the
test may alter results.
INDICATIONS FOR PARATHYROID HORMONE
TEST

Suspected hyperparathyroidism:
Elevated levels occur in primary hyperparathyroidism as a result of hyperplasia or tumor of
the parathyroid glands.
Elevated levels also may occur in secondary
hyperparathyroidism (usually as a result of
chronic renal failure, malignant tumors that
produce ectopic PTH, and malabsorption
syndromes).
Suspected surgical removal of the parathyroid
glands or incidental damage to them during
thyroid or neck surgery, as indicated by decreased
levels
Evaluation of parathyroid response to altered
serum calcium levels, with elevated serum
calcium levels, especially those resulting from
malignant processes, leading to decreased PTH
production
Evaluation of parathyroid response to other
disorders that may lead to decreased PTH
production (e.g., hypomagnesemia, autoimmune
destruction of the parathyroid glands)51
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
any study involving collection of a peripheral blood
sample (see Appendix I).
For this test, the client should fast from food for at
least 8 hours before collection of the sample.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. A sample for serum

NURSING CARE AFTER THE PROCEDURE

Adrenal Hormones
Adrenal hormones are secreted by two functionally
and embryologically distinct portions of the adrenal
gland. The adrenal cortex, which is of mesodermal
origin, secretes three types of steroids: (1) glucocorticoids, which affect carbohydrate metabolism; (2)
mineralocorticoids, which promote potassium
excretion and sodium retention by the kidneys; and
(3) adrenal androgens, which the liver converts to
testosterone. Cortisol is the predominant glucocorticoid, whereas aldosterone is the predominant
mineralocorticoid. Production and secretion of
cortisol and adrenal androgens are stimulated by
ACTH. Although ACTH also may enhance aldosterone production, the usual stimulants are either
increased serum potassium or decreased serum
sodium.
The adrenal medulla, which constitutes only
about one-tenth of the volume of the adrenal glands,
derives from the ectoderm and physiologically
belongs to the sympathetic nervous system. The
hormones secreted by the adrenal medulla are
epinephrine and norepinephrine, which are collectively known as the catecholamines. Epinephrine is

178

SECTION I—Laboratory

Tests

secreted in response to sympathetic stimulation,
hypoglycemia, or hypotension. Most norepinephrine is manufactured by and secreted from sympathetic nerve endings; only a small amount is
normally secreted by the adrenal medulla.52

CORTISOL
Cortisol (hydrocortisone), the predominant glucocorticoid, is secreted in response to stimulation by
ACTH. Ninety percent of cortisol is bound to cortisol-binding globulin (CBG) and albumin; the free
portion is responsible for its physiological effects.
Cortisol stimulates gluconeogenesis, mobilizes fats
and proteins, antagonizes insulin, and suppresses
inflammation. Cortisol secretion varies diurnally,
with the highest levels seen upon awakening and the
lowest levels occurring late in the day. Bursts of
cortisol excretion also may occur at night.
Elevated cortisol levels occur in Cushing’s
syndrome, in which there is excessive production of
adrenocorticosteroids. Cushing’s syndrome may be
caused by pituitary adenoma, adrenal hyperplasia,
benign or malignant adrenal tumors, and nonendocrine malignant tumors that secrete ectopic
ACTH. Therapy with adrenocorticosteroids also
may produce cushingoid signs and symptoms.
Elevated cortisol levels are additionally associated
with stress, hyperthyroidism, obesity, and diabetic
ketoacidosis.
Decreased cortisol levels occur with Addison’s
disease, in which there is deficient production of
adrenocorticosteroids. Addison’s disease is usually
caused by idiopathic adrenal hypofunction,
although it may also be seen in pituitary hypofunction, hypothyroidism, tuberculosis, metastatic
cancer involving the adrenal glands, amyloidosis,
and hemochromatosis. Addison’s disease may occur
after withdrawal of corticosteroid therapy because of
drug-induced atrophy of the adrenal glands.

CORTISOL/ACTH CHALLENGE TESTS
A variety of tests that stimulate or suppress cortisol/ACTH levels can be used further to evaluate

individuals with signs and symptoms of adrenal
hypofunction or hyperfunction or abnormal cortisol
levels.
Dexamethasone is a potent glucocorticoid that
suppresses ACTH and cortisol production. In the
rapid dexamethasone test, 1 mg of oral dexamethasone is given at midnight; cortisol levels are then
measured at 8 AM. Normally, plasma cortisol should
be no more than 5 to 10 mg/dL after dexamethasone
administration. A 5-hour urine collection test for
17-hydroxycorticoids (17-OHCS), metabolites of
glucocorticoids, also may be collected as part of the
test. Elevated plasma cortisol levels in response to
dexamethasone administration are associated with
Cushing’s syndrome.
Metyrapone is a drug that inhibits certain
enzymes required to convert precursor substances
into cortisol. When the drug is administered, plasma
cortisol levels decrease and ACTH levels subsequently increase in response. The test involves
mainly measurement of urinary excretion of 17OHCS, which should rise if the adenohypophysis is
normally responsive to decreased cortisol levels.
Plasma cortisol levels are measured to ensure that
sufficient suppression has been induced by the
metyrapone such that test results will be valid.
Insulin-induced hypoglycemia (serum glucose of
50 mg/dL or less) also stimulates ACTH production.
Adenohypophyseal response to hypoglycemia is
usually measured indirectly by plasma cortisol levels
because the test is more universally available. A
normal response is an increase of 6 g/dL or more
over baseline cortisol levels. Lack of response to
hypoglycemic stimulation indicates either pituitary
or adrenal hypofunction. They can be differentiated
either by directly measuring plasma ACTH levels or
by administering ACTH preparations and observing
cortisol response.
Purified exogenous ACTH or synthetic ACTH
preparations (e.g., cosyntropin) may be used diagnostically to stimulate cortisol secretion. The usual
response is an increase in plasma cortisol levels of 7
to 18 g/dL over baseline levels within 1 hour of
ACTH administration. Lack of response indicates
adrenal insufficiency.53

Reference Values
8 AM
Conventional Units

4 PM
SI Units

Conventional Units

SI Units

Children

15–25 g /dL

410–690 nmol/L

5–10 g/dL

140–280 nmol/L

Adults

9–24 g /dL

250–690 nmol/L

3–12 g/dL

80–330 nmol/L

CHAPTER 5—Blood

INTERFERING FACTORS

The time of day when the test is performed may
alter results because cortisol levels vary diurnally,
with highest levels being seen on awakening and
lowest levels occurring late in the day.
Stress and excessive physical activity may produce
elevated levels.
Pregnancy, therapy with estrogen-containing
drugs, lithium carbonate, methadone, and ethyl
alcohol may lead to elevated cortisol levels.
Therapy with levodopa, barbiturates, phenytoin
(Dilantin), and androgens may produce decreased
levels.
Failure to follow dietary restrictions, if ordered,
may alter test results.
INDICATIONS FOR CORTISOL ASSAY

Suspected adrenal hyperfunction (Cushing’s
syndrome) from a variety of causes, as indicated
by elevated levels that do not vary diurnally
Evaluation of effects of disorders associated with
elevated cortisol levels (e.g., hyperthyroidism,
obesity, and diabetic ketoacidosis)
Suspected adrenal hypofunction (Addison’s
disease) from a variety of causes, as indicated by
decreased levels
Monitoring for response to therapy with adrenocorticosteroids:
Elevated levels are seen in clients receiving
adrenocorticosteroid therapy.
Decreased levels may occur for months after
therapy is discontinued, resulting from druginduced atrophy of the adrenal glands.
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
study involving collection of a peripheral blood
sample (see Appendix I).
Some laboratories require an 8-hour fast and
activity restriction before the test. Medications
that may alter cortisol levels should be withheld
for 12 to 24 hours before the study, although this
practice should be confirmed with the person
ordering the test.
The client should be informed that it may be
necessary to obtain more than one sample and
that samples must be obtained at specific times to
detect peak and trough levels of cortisol.
THE PROCEDURE

At approximately 8 AM, a venipuncture is performed
and the sample is collected in a green-topped tube.
The sample should be handled gently to avoid
hemolysis and sent promptly to the laboratory. If
cortisol hypersecretion is suspected, then a second

Chemistry

179

sample may be obtained at approximately 4 PM to
determine whether diurnal variation in cortisol
levels is occurring.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume food and any medications withheld
before the test, as well as usual activities.
Increased levels: Note and report increased levels
in relation to urinary cortisol, serum glucose, and
calcium. Assess potential for infection, fluid
volume excess (weight gain, edema, increased
blood pressure), hyperglycemia (thirst, polyuria,
polydipsia), mood changes (euphoria, psychosis),
poor body image (moon face, buffalo hump on
the back, acne, hair growth in undesirable areas in
women, obese trunk, and thin extremities), and
bone or joint pain. Monitor I&O. Provide support
for psychophysiological changes. Help client to
develop coping skills. Instruct client to increase
dietary protein; decrease sodium, calories, and
carbohydrates; and avoid infections.
Decreased levels: Note and report decreased
levels in relation to electrolyte panel (hyponatremia, hyperkalemia) and serum glucose for
hypoglycemia. Assess for fluid volume deficit,
long-term administration of corticosteroid therapy, and changes in body image (pigmentation of
the skin, masculinization in women). Monitor
I&O. Administer ordered corticosteroid regimen.
Provide support for physical changes affecting
body image. Advise client to avoid situations that
cause stress or anxiety. Instruct client in longterm supplemental or replacement cortisone regimen.

ALDOSTERONE
Aldosterone, the predominant mineralocorticoid, is
secreted by the zona glomerulosa of the adrenal
cortex in response to decreased serum sodium,
decreased blood volume, and increased serum
potassium. It is thought that altered serum sodium
and potassium levels directly stimulate the adrenal
cortex to release aldosterone. In addition, decreased
blood volume and altered sodium and potassium
levels stimulate the juxtaglomerular apparatus of the
kidney to secrete renin. Renin is subsequently
converted to angiotensin II, which then stimulates
the adrenal cortex to secrete aldosterone. In normal
states, ACTH does not play a major role in aldosterone secretion. In disease or stress states, however,
ACTH may also enhance aldosterone secretion.

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Aldosterone increases sodium reabsorption in the
renal tubules, gastrointestinal tract, salivary glands,
and sweat glands. This subsequently results in
increased water retention, blood volume, and blood
pressure. Aldosterone also increases potassium
excretion by the kidneys in exchange for the sodium
ions that are retained.

ALDOSTERONE CHALLENGE TESTS
In normal individuals, increased serum sodium
levels and blood volume suppress aldosterone secretion. In primary aldosteronism, however, this
response is not seen. Serum sodium levels may be
elevated through ingestion of a high-sodium diet for
approximately 4 days or by infusing 2 L of normal
saline intravenously. If appropriate control of aldosterone levels is managed through negative feedback
systems and the renin–angiotensin system, plasma
aldosterone levels will be low normal or decreased in
response to the increased sodium load.
Fludrocortisone acetate (Florinef), a synthetic
mineralocorticoid, produces the same effect after 3
days of administration. Aldosterone challenges are
used to differentiate between primary and secondary
hyperaldosteronism.54
Reference Values
Conventional Units

SI Units

Supine

3–9 ng/dL

0.08–0.30 nmol/L

Standing

5–30 ng/dL

0.14–0.80 nmol/L

INTERFERING FACTORS

Upright body posture (see “Nursing Care Before
the Procedure” section), stress, and late pregnancy
may lead to increased levels.
Therapy with diuretics, hydralazine (Apresoline),
diazoxide (Hyperstat), and nitroprusside may lead
to elevated levels.
Excessive licorice ingestion may produce
decreased levels, as may therapy with propranolol
and fludrocortisone (Florinef).
Altered serum electrolyte levels affect aldosterone
secretion.
Decreased serum sodium and elevated serum
potassium increase aldosterone secretion.
Elevated serum sodium and decreased serum
potassium suppress aldosterone secretion.
INDICATIONS FOR PLASMA ALDOSTERONE TEST

Suspected hyperaldosteronism as indicated by
elevated levels:

Primary aldosteronism (e.g., resulting from
benign adenomas or bilateral hyperplasia of
the aldosterone-secreting zona glomerulosa
cells) is indicated by elevated aldosterone and
low plasma renin levels.
Secondary hyperaldosteronism (e.g., resulting
from changes in blood volume and serum
electrolytes, CHF, cirrhosis, nephrotic syndrome, chronic obstructive pulmonary disease
[COPD], and renal artery stenosis) is indicated
by elevated aldosterone and plasma renin levels.
Suspected hypoaldosteronism (e.g., as seen in
diabetes mellitus and toxemia of pregnancy) as
indicated by decreased levels
Evaluation of hypertension of unknown etiology
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
study involving the collection of a peripheral blood
sample (see Appendix I).
The client should not have ingested licorice for 2
weeks before the test. Medications that alter
plasma aldosterone levels also may be withheld
for up to 2 weeks before the test, although this
practice should be confirmed with the person
ordering the study.
If hospitalized, the client should be told not to get
out of bed in the morning until the sample has
been obtained and that it may be necessary to
obtain a second sample after he or she has been up
for about 2 to 4 hours.
Nonhospitalized individuals should be instructed
on when to report to the laboratory in relation to
the length of time to be upright before the test.
THE PROCEDURE

A venipuncture is performed and the sample is
collected in a red-, green-, or lavender-topped tube,
depending on laboratory procedures. The client’s
position and length of time the position was held
should be noted on the laboratory request form. The
sample(s) should be handled gently to avoid hemolysis and sent to the laboratory immediately. A
sample for plasma renin also may be obtained in
conjunction with the test.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Increased levels: Note and report increased levels
related to urinary aldosterone levels. Assess for
fluid volume excess caused by sodium and fluid
retention, and administer ordered diuretics.

CHAPTER 5—Blood

Chemistry

181

Reference Values
Conventional Units
Epinephrine and norepinephrine

SI Units

100–500 ng/L

Epinephrine
Supine

0–110 pg/mL

0–600 pmol/L

Standing

0–140 pg/mL

0–764 pmol/L

Supine

70–750 pg/mL

413–4432 pmol/L

Standing

200–1700 pg/mL

1,182–10,047 pmol/L

Norepinephrine

Note: Results are usually evaluated in relation to urinary measurements of catecholamine metabolites. Several
measurements of plasma levels may also be indicated.

Decreased levels: Note and report decreased
levels related to sodium levels. Assess for fluid
volume deficit. Instruct in sodium and corticosteroid replacement regimen.

CATECHOLAMINES
The adrenal medulla, a component of the sympathetic nervous system, secretes epinephrine and
norepinephrine, which are collectively known as the
catecholamines. A third catecholamine, dopamine, is
secreted in the brain, where it functions as a neurotransmitter.
Epinephrine (adrenalin) is secreted in response to
generalized sympathetic stimulation, hypoglycemia,
or arterial hypotension. It increases the metabolic
rate of all cells, heart rate, arterial blood pressure,
and levels of blood glucose and free fatty acids, and
it decreases peripheral resistance and blood flow to
the skin and kidneys.
Norepinephrine is secreted by sympathetic nerve
endings, as well as by the adrenal medulla, in
response to sympathetic stimulation and the presence of tyramine. It decreases the heart rate, while
increasing peripheral vascular resistance and arterial
blood pressure. Normally, norepinephrine is the
predominant catecholamine.
The only clinically significant disorder involving
the adrenal medulla is the catecholamine-secreting
tumor, pheochromocytoma. Catecholamineproducing tumors also can originate along sympathetic paraganglia; these tumors are known as
functional paragangliomas. Pheochromocytomas
may release catecholamines, primarily epinephrine,
continuously or intermittently. Because the most
common sign of pheochromocytoma is arterial
hypertension, measurement of plasma catecholamines (or the urinary metabolites thereof) is indicated in evaluating new-onset hypertension.55

INTERFERING FACTORS

Catecholamine levels vary diurnally and with
postural changes.
Shock, stress, hyperthyroidism, strenuous exercise, and smoking may produce elevated plasma
catecholamines.
Dopamine, norepinephrine (Levophed), sympathomimetic drugs, tricyclic antidepressants, methyldopa, hydralazine, quinidine, and
isoproterenol (Isuprel) may produce elevated
levels.
A diet high in amines (e.g., bananas, nuts, cereal
grains, tea, coffee, cocoa, aged cheese, beer, ale,
certain wines, avocados, and fava beans) may
produce elevated plasma catecholamine levels,
although this effect is more likely to be seen in
relation to certain urinary metabolites.
INDICATIONS FOR PLASMA CATECHOLAMINES
TEST

Hypertension of unknown etiology or suspected
pheochromocytoma or paragangliomas or both
Identification of pheochromocytoma as the cause
of hypertension as indicated by elevated combined catecholamine and epinephrine levels
Support for diagnosing paragangliomas as indicated by elevated combined catecholamine and
norepinephrine levels
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
study involving the collection of a peripheral blood
sample (see Appendix I).
For this test, the client should fast for 12 hours
and abstain from smoking for 24 hours before the
test. Vigorous exercise should be avoided, with
provision made for rest in a recumbent position
for at least 1 hour before the study.

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Tests

Medications that may alter test results, especially
over-the-counter cold preparations containing
sympathomimetics, may be withheld for up to 2
weeks before the test, although this practice
should be confirmed with the person ordering the
study.
The need for dietary restriction of amine-rich
foods for 48 hours before the test should be
confirmed with the laboratory performing the test
or the person ordering it.
If samples are to be obtained via an intermittent
venous access device (e.g., heparin lock), the
client should be informed of its purpose and that
it may be inserted as long as 24 hours before the
test.

steroids, and their molecular structures and those of
the adrenocorticosteroids are quite similar.
Moreover, small amounts of the gonadal hormones
or precursors thereof are secreted by the adrenal
glands in both men and women.
Secretion of gonadal hormones is regulated via
the hypothalamic–hypophyseal system. When blood
levels of gonadal hormones decline, the hypothalamus is stimulated to release gonadotropin-releasing
hormone, which then stimulates the adenohypophysis to release its gonadotropic hormones. These
tropic hormones are called, in both men and
women, follicle-stimulating hormone and luteinizing hormone, even though the ovarian follicle and
corpus luteum are unique to women.

THE PROCEDURE

If more than one sample is to be obtained, a heparin
lock should be inserted 12 to 24 hours before the
test; the stress of repeated venipunctures could
falsely elevate levels.
For hospitalized individuals, a sample of venous
blood should be collected in a chilled lavendertopped tube between 6 and 8 AM. For nonhospitalized clients, the first sample should be obtained
after approximately 1 hour of rest in a recumbent
position. The sample is handled gently to avoid
hemolysis, packed in ice, and sent to the laboratory immediately.
The client should then be helped to stand for 10
minutes, after which a second sample is obtained.
The time(s) of collection and the position of the
client should be noted on the laboratory request
form.
NURSING CARE AFTER THE PROCEDURE

If an intermittent venous access device was inserted,
remove after completion of the test and apply a pressure bandage to the site.
Resume foods and any medications withheld
before the test, as well as usual activities.
Abnormal levels: Note increased levels in relation
to 24-hour urinary vanillylmandelic acid (VMA)
and metanephrine levels. Assess for pulse and
blood pressure increases, hyperglycemia, shakiness, and palpitations associated with increased
values.

Gonadal Hormones
The gonadal hormones, secreted primarily by the
ovaries and testes, include estrogens, progesterone,
and testosterone. These hormones are essential for
normal sexual development and reproductive function in men and women. All gonadal hormones are

ESTROGENS
Estrogens are secreted in large amounts by the
ovaries and, during pregnancy, by the placenta.
Minute amounts are secreted by the adrenal glands
and, possibly, by the testes. Estrogens induce and
maintain the female secondary sex characteristics,
promote growth and maturation of the female
reproductive organs, influence the pattern of fat
deposition that characterizes the female form, and
cause early epiphyseal closure. They also promote
retention of sodium and water by the kidneys and
sensitize the myometrium to oxytocin.
Elevated estrogen levels are associated with ovarian and adrenal tumors as well as estrogen-producing tumors of the testes. Decreased levels are
associated with primary and secondary ovarian failure, Turner’s syndrome, hypopituitarism,
adrenogenital syndrome, Stein-Leventhal syndrome,
anorexia nervosa, and menopause. Estrogen levels
vary in relation to the menstrual cycle.
Many different types of estrogens have been identified, but only three are present in the blood in
measurable amounts: estrone, estradiol, and estriol.
Estrone (E1) is the immediate precursor of estradiol
(E2), which is the most biologically potent of the
three. In addition to ovarian sources, estriol (E3) is
secreted in large amounts by the placenta during
pregnancy from precursors produced by the fetal
liver. Through radioimmunoassay, plasma levels of
E2 and E3 can be determined. Total plasma estrogen
levels are difficult to measure and are not routinely
performed.
INTERFERING FACTORS

In menstruating women, estrogen levels vary in
relation to the menstrual cycle.
Therapy with estrogen-containing drugs and

CHAPTER 5—Blood

Chemistry

183

Reference Values
Conventional Units

SI Units

Estradiol (E2)
Children under 6 yr

3–10 pg/mL

10–36 pmol/L

12–34 pg/mL

40–125 pmol/L

Early cycle

24–68 pg/mL

90–250 pmol/L

Midcycle

50–186 pg/mL

200–700 pmol/L

Late cycle

73–149 pg/mL

250–550 pmol/L

30–32

2–12 ng/mL

7–40 nmol/L

33–35

3–19 ng/mL

10–65 nmol/L

36–38

5–27 ng/mL

15–95 nmol/L

39–40

10–30 ng/mL

35–105 nmol/L

Adults
Men
Women (menstruating)

Estriol (E3)
Weeks of pregnancy

adrenocorticosteroids will elevate levels, whereas
clomiphene will decrease them.
INDICATIONS FOR ESTROGENS TEST

Infertility or amenorrhea of unknown etiology,
with primary or secondary ovarian failure indicated by low estradiol (E2) levels
Establishment of the time of ovulation
Evaluation of response to therapy for infertility
Suspected precocious puberty with the disorder
indicated by elevated estradiol (E2) levels
Suspected estrogen-producing tumors, as indicated by consistently high estradiol (E2) levels
without normal cyclic variations
High-risk pregnancy with suspicion of fetal
growth retardation, placental dysfunction, or
impending fetal jeopardy, as indicated by
decreased estriol (E3) levels relative to the stage of
pregnancy
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving collection of a peripheral blood sample
(see Appendix I).
It is recommended that drugs known to alter
estrogen levels be withheld for 12 to 24 hours
before the test, although this practice should be
confirmed with the person ordering the study.
In menstruating women, the phase of the
menstrual cycle should be ascertained, if possible.

If the test is being conducted to detect ovulation,
the client should be informed that it may be
necessary to obtain a series of samples over a
period of several days to detect the normal variation in estrogen levels.
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Complications and precautions: Assess increased
or decreased levels in relation to age, gender, pregnancy, and menopausal status and in relation to
associated levels of 24-hour urinary analysis and
serum estradiol and estriol levels.

PROGESTERONE
Progesterone is secreted in nonpregnant women
during the latter half of the menstrual cycle by the
corpus luteum and in large amounts by the placenta
during pregnancy. It also is secreted in minute
amounts by the adrenal cortex in both men and

184

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Tests

Reference Values
Conventional Units

SI Units

100 ng/dL

3 nmol/L

Follicular phase

150 ng/dL

5 nmol/L

Luteal phase

300–1200 ng/dL

10–40 nmol/L

First trimester

1500–5000 ng/dL

50–160 nmol/L

Second and third trimesters

8,000–20,000 ng/dL

250–650 nmol/L

Women (menopausal)

10–22 ng/dL

2 nmol/L

Men
Women (menstruating)

Women (pregnant)

women. Progesterone prepares the endometrium for
implantation of the fertilized ovum, decreases
myometrial excitability, stimulates proliferation of
the vaginal epithelium, and stimulates growth of the
breasts during pregnancy. Although progesterone
may promote sodium and water retention, its effect
is weaker than that of aldosterone, which it directly
antagonizes. The net effect is loss of sodium and
water from the body.
INTERFERING FACTORS

In menstruating women, progesterone levels vary
in relation to the menstrual cycle.
Therapy with estrogen, progesterone, or adrenocorticosteroids may produce elevated levels.
INDICATIONS FOR PLASMA PROGESTERONE TEST

Infertility of unknown etiology with failure to
ovulate, indicated by low levels throughout the
menstrual cycle
Evaluation of response to therapy for infertility
Support for diagnosing disorders associated with
elevated progesterone levels (e.g., precocious
puberty, ovarian tumors or cysts, and adrenocortical hyperplasia and tumors)
High-risk pregnancy with suspicion of placental
dysfunction, fetal abnormality, impending fetal
jeopardy, threatened abortion, or toxemia of pregnancy, as indicated by lower than expected levels
for the stage of pregnancy
Support for diagnosing disorders associated with
decreased progesterone levels (e.g., panhypopituitarism, Turner’s syndrome, adrenogenital
syndrome, and Stein-Leventhal syndrome)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).

It is recommended that any drugs that may alter
progesterone levels be withheld for 12 to 24 hours
before the test, although this practice should be
confirmed with the person ordering the study.
In menstruating women, the phase of the
menstrual cycle should be ascertained, if possible.
If the test is being performed to detect ovulation,
the client should be informed that it may be
necessary to obtain a series of samples over a
period of several days to detect the normal variation in progesterone levels.
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Complications and precautions: Assess increased
or decreased levels in relation to age, menstrual or
pregnancy status, and 24-hour urinary pregnanediol level.

TESTOSTERONE
Testosterone is produced in men by the Leydig cells
of the testes. Minute amounts also are secreted by
the adrenal glands in men and women and by the
ovaries in women. In the male fetus, testosterone is
secreted by the genital ridges and fetal testes.
Testosterone is produced in response to stimulation by luteinizing hormone, which is secreted by
the adenohypophysis in response to stimulation
by gonadotropin-releasing hormone. Testosterone

CHAPTER 5—Blood

Chemistry

185

Reference Values
Conventional Units

SI Units

0.12–0.16 ng/mL

0.41–0.55 nmol/L

60 yr

3.9–7.9 ng/mL

13.59–27.41 nmol/L

60 yr

1.5–3.1 ng/dL

5.20–10.75 nmol/L

Menstruating

0.25–0.67 ng/mL

0.87–2.32 nmol/L

Menopausal

0.21–0.37 ng/mL

0.72–1.28 nmol/L

Children
Men

Women

promotes development of the male sex organs and
testicular descent in the fetus, induces and maintains
secondary sexual characteristics in men, promotes
protein anabolism and bone growth, and enhances
sodium and water retention to some degree.
INTERFERING FACTORS

Testosterone levels vary diurnally, with highest
levels occurring in the early morning.
Administration of testosterone, thyroid and
growth hormones, clomiphene, and barbiturates
may lead to elevated levels.
Therapy with estrogens and spironolactone
(Aldactone) may produce decreased levels.
INDICATIONS FOR TESTOSTERONE TEST

In men, support for diagnosing precocious
puberty, testicular tumors, and benign prostatic
hypertrophy, as indicated by elevated levels
In women, support for diagnosing adrenogenital
syndrome, adrenal tumors or hyperplasia, SteinLeventhal syndrome, ovarian tumors or hyperplasia, and luteomas of pregnancy, as indicated by
elevated levels
In men and women, support for diagnosing
nonendocrine tumors that produce ACTH ectopically, as indicated by elevated levels without diurnal variation
In men, support for diagnosing infertility, with
testicular failure indicated by decreased levels
Support for diagnosing other disorders associated
with decreased testosterone levels (e.g., hypopituitarism, Klinefelter’s syndrome, cryptorchidism
[failure of testicular descent], and cirrhosis)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
It is recommended that drugs that may alter

testosterone levels be withheld for 12 to 24 hours
before the test, although this practice should be
confirmed with the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample collected in either a red- or a green-topped tube, depending on the laboratory performing the test. The
sample should be handled gently to avoid hemolysis
and transported promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Complications and precautions: Assess increased
or decreased levels in relation to age, gender,
menstrual or menopausal status, as well as possible sexual dysfunction and medicolegal aspects of
the abuse of anabolic steroids related to athletic
ability.

Placental Hormones
During pregnancy, the placenta secretes estrogens,
progesterone, human chorionic gonadotropin
(hCG), and human placental lactogen (hPL).
Estrogens and progesterone, which are not specific
to pregnancy, are discussed in the preceding
sections. In contrast, hCG and hPL are fairly specific
to pregnancy, but levels may also be altered in individuals with trophoblastic tumors (e.g., hydatidiform mole, choriocarcinoma) and tumors that
ectopically secrete placental hormones.

HUMAN CHORIONIC GONADOTROPIN
Human chorionic gonadotropin (hCG) is a glycoprotein that is unique to the developing placenta. Its

186

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Tests

presence in blood and urine has been used for
decades to detect pregnancy. Tests using rabbits,
frogs, and rats, however, have now been replaced by
immunologic tests that use antibodies to hCG.
Earlier immunologic tests were not always reliable,
because the antibody used could cross-react with
other glycoprotein hormones such as luteinizing
hormone. Furthermore, it was sometimes not possible to obtain reliable results until 4 to 8 weeks after
the first missed period. Currently, more sensitive and
specific tests use antibody that reacts only with the
subunit of hCG, not with other hormones. The most
sensitive of the radioimmunoassays for hCG can
detect elevated levels within 8 to 10 days after
conception, even before the first missed period.
Because hCG is associated with the developing
placenta, it is secreted at increasingly higher levels
during the first 2 months of pregnancy, declines
during the third and fourth months, and then
remains relatively stable until term. Levels return to
normal within 1 to 2 weeks of termination of pregnancy. Human chorionic gonadotropin prevents the
normal involution of the corpus luteum at the end
of the menstrual cycle and stimulates it to double in
size and produce large quantities of estrogen and
progesterone. It is also thought to stimulate the
testes of the male fetus to produce testosterone and
to induce descent of the testicles into the scrotum.
INDICATIONS FOR HUMAN CHORIONIC
GONADOTROPIN TEST

Suspected testicular tumor as indicated by
elevated levels
Support for diagnosing nonendocrine tumors
that produce hCG ectopically (e.g., carcinoma of
the stomach, liver, pancreas, and breast; multiple
myeloma; and malignant melanoma), as indicated
by elevated levels
Monitoring for the effectiveness of treatment for
malignancies associated with ectopic hCG
production, as indicated by decreasing levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and sent
promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Complications and precautions: Relate age,
gender, and time of gestation to the test results.

HUMAN PLACENTAL LACTOGEN

Early detection of pregnancy (i.e., within 8 to 10
days of conception), especially in women with a
history of infertility or habitual abortion
Prediction of outcome in threatened abortion
(levels below 10,000 mIU/mL are highly predictive that abortion will occur)
Suspected intrauterine fetal demise or incomplete
abortion as indicated by decreased levels56
Suspected hydatidiform mole or choriocarcinoma
as indicated by elevated levels

Human placental lactogen (hPL), also known as
human chorionic somatotropin (hCS), is produced
by the placenta but exerts its known effect on the
mother. Human placental lactogen causes decreased
maternal sensitivity to insulin and causes utilization
of glucose, thus increasing the glucose available to
the fetus. It also promotes release of maternal free
fatty acids for utilization by the fetus. It is also
thought that hPL stimulates the action of growth
hormone in protein deposition, promotes breast

Reference Values
Conventional Units

SI Units

3 mIU/mL

3 IU/L

8–10 days

5–40 mIU/mL

5–40 IU/L

1 mo

100 mIU/mL

100 IU/L

2 mo

100,000 mIU/mL

100,000 IU/L

4 mo–term

50,000 mIU/mL

50,000 IU/L

Nonpregnant women
Pregnant women

CHAPTER 5—Blood

Chemistry

187

Reference Values
Conventional Units

SI Units

0.5 g/mL

Not detected

0.5 g/mL

Not detected

5–27 weeks

4.6 g/mL

4.6 mg/L

28–31 weeks

2.4–6.1 g/mL

2.4–6.1 mg/L

32–35 weeks

3.7–7.7 g/mL

3.7–7.7 mg/L

36 weeks–term

5.0–8.6 g/mL

5.0–8.6 mg/L

Diabetic at term

10–12 g/mL

10.0–12.0 mg/L

Men
Women
Nonpregnant
Pregnant

growth and preparation for lactation, and maintains
the pregnancy by altering the endometrium.
Human placental lactogen rises steadily through
pregnancy, maintaining a high plateau during the
last trimester. Blood levels of hPL correlate with
placental weight and tend to be high in diabetic
mothers. Levels also may be elevated in multiple
pregnancy and Rh isoimmunization, as well as in
nonendocrine tumors that secrete ectopic hPL.
During pregnancy, hPL levels vary greatly with
the individual as well as on a day-to-day basis. Thus,
serial determinations may be necessary with the
client serving as her own control.57
INTERFERING FACTORS

During pregnancy, hPL levels vary greatly with
the individual as well as on a day-to-day basis.
Levels tend to be higher in diabetic mothers,
multiple gestation, and Rh isoimmunization.
INDICATIONS FOR HUMAN PLACENTAL
LACTOGEN TEST

Detection of placental insufficiency as evidenced
by low hPL levels in relation to gestational age
Support for diagnosing intrauterine growth retardation caused by placental insufficiency, as indicated by hPL levels of less than 4 g/mL,
especially when blood estrogen levels are low
Prediction of outcome in threatened abortion as
indicated by lower than expected levels for the
stage of pregnancy
Support for diagnosing hydatidiform mole and
choriocarcinoma as indicated by decreased levels
Support for diagnosing malignancies associated
with elevated levels (e.g., nonendocrine tumors
that secrete ectopic hPL)

Monitoring for the effectiveness of treatment for
malignancies associated with ectopic hPL production as indicated by decreasing levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
The pregnant client should be informed that
several determinations may be necessary throughout the pregnancy.
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.

Pancreatic Hormones
The islets of Langerhans, the endocrine cells of the
pancreas, produce at least three glucose-related
hormones: (1) insulin, which is produced by the beta
cells; (2) glucagon, which is produced by the alpha
cells; and (3) somatostatin, which is produced by the
delta cells.
The overall effect of insulin is to promote glucose
utilization and energy storage. It accomplishes this
by enhancing glucose and potassium entry into most
body cells, stimulating glycogen synthesis in liver
and muscle, promoting the conversion of glucose to

188

SECTION I—Laboratory

Tests

Reference Values
Conventional Units

SI Units

8.0–15.0 U/mL or 0.3–0.6 ng/mL

55–104 pmol/L

25–231 U/mL

173–1604 pmol/L

1 hr

18–276 U/mL

125–1916 pmol/L

2 hr

16–166 U/mL

111–1152 pmol/L

3 hr

4–38 U/mL

27–263 pmol/L

Insulin-to-glucose ratio

0.3:1

Fasting
After 100 g glucose
1

/2 hr

fatty acids and triglycerides, and enhancing protein
synthesis. It exerts its effects by interacting with cell
surface receptors.
In contrast to insulin, glucagon increases blood
glucose levels by stimulating the breakdown of
glycogen and the release of glucose stored in the
liver. Somatostatin inhibits secretion of both insulin
and glucagon. It also inhibits release of growth
hormone, thyroid-stimulating hormone, and
adrenocorticotropic hormone by the adenohypophysis and may decrease production of parathormone,
calcitonin, and renin. In addition, it is thought to
inhibit secretion of gastric acid and gastrin. The
exact physiological roles of glucagon and somatostatin are unknown.
Blood levels of insulin are measured by radioimmunoassay and can be determined in most laboratories. Samples for blood glucagon levels require
special handling, and tests for its presence may not
be routinely available in all laboratories.
Somatostatin may be measured but this test is not
routinely performed. C-peptide, a metabolically
inactive peptide chain formed during the conversion
of proinsulin to insulin, may be measured to provide
an index of -cell activity not affected by exogenous
insulin.

INSULIN
Insulin is secreted by the cells in response to
elevated blood glucose, certain amino acids, ketones,
fatty acids, cortisol, growth hormone, glucagon,
gastrin, secretin, cholecystokinin, gastric inhibitory
peptide, estrogen, and progesterone. Because of
normal feedback mechanisms, high insulin levels
inhibit secretion of insulin. Elevated blood levels of
somatostatin, epinephrine, and norepinephrine also
inhibit insulin secretion.
Abnormally elevated serum insulin levels are seen
with insulin- and proinsulin-secreting tumors

(insulinomas), with reactive hypoglycemia in developing diabetes mellitus, and with excessive administration of exogenous insulin.
A blood glucose level is usually obtained with the
serum insulin determination. Serum insulin levels
may also be measured when glucose tolerance tests
are performed.
INTERFERING FACTORS

Administration of insulin or oral hypoglycemic
agents within 8 hours of the test may lead to
falsely elevated levels.
Failure to follow dietary restrictions before the
test may lead to falsely elevated levels.
Therapy with drugs containing estrogen and
progesterone may produce elevated levels.
INDICATIONS FOR SERUM INSULIN TEST

Evaluation of postprandial (“reactive”) hypoglycemia of unknown etiology
Support for diagnosing early or developing noninsulin-dependent diabetes mellitus as indicated
by excessive production of insulin in relation to
blood glucose levels (best demonstrated with
glucose tolerance tests or 2-hour postprandial
tests)
Confirmation of functional hypoglycemia (i.e., no
known physiological cause for the hypoglycemia)
as indicated by circulating insulin levels appropriate to changing blood glucose levels
Evaluation of fasting hypoglycemia of unknown
etiology
Support for diagnosing insulinoma as indicated
by sustained high levels of insulin and absence of
blood glucose-related variations
Evaluation of uncontrolled insulin-dependent
diabetes mellitus
Differentiation between insulin-resistant diabetes,
in which insulin levels are high, and non-insulinresistant diabetes, in which insulin levels are low

CHAPTER 5—Blood

Support for diagnosing pheochromocytoma as
indicated by decreased levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for the related
blood glucose test (e.g., fasting blood glucose,
glucose tolerance test) with which the serum insulin
determination is performed.
THE PROCEDURE

The general procedure is the same as that for the
related blood glucose test. Blood samples for serum
insulin determinations are obtained in red-topped
tubes and then packed in ice. The samples should be
handled gently to avoid hemolysis and sent immediately to the laboratory.

Chemistry

189

INDICATIONS FOR C-PEPTIDE TEST

Suspected excessive insulin administration in
either diabetic or nondiabetic individuals, as indicated by low C-peptide and elevated serum
insulin levels
Determination of -cell function when insulin
antibodies preclude accurate measurement of
serum insulin production (Insulin antibodies
are most common in diabetic clients receiving exogenous insulin prepared from animal
extracts.)
Support for diagnosing insulinoma, especially
when the tumor secretes more proinsulin than
active hormone, because the normal correlation
between insulin and C-peptide will be altered

NURSING CARE AFTER THE PROCEDURE

NURSING CARE BEFORE THE PROCEDURE

Care and assessment after the procedure are the
same as for the related blood glucose test.
Assess the client for signs of hypoglycemia, which
may occur in response to fasting or excessive
blood glucose load.
Resume foods and any medications withheld
before the test.
Abnormal values: Note and report decreased or
increased levels and relation to type I or II
diabetes mellitus, respectively, and response to
glucose intake.

Client preparation is the same as that for any test
involving the collection of a peripheral blood sample
(see Appendix I).
Some laboratories may require that the client fast
from food for 8 hours before the test.

Critical values: Notify the physician at once if
fasting level is greater than 30 U/mL. Prepare
client for glucose administration.

C-PEPTIDE
Measurement of C-peptide, which is accomplished
through radioimmunoassay techniques, provides an
index of -cell activity that is unaffected by the
administration of exogenous insulin. As the cells
release insulin, they also release equimolar amounts
of metabolically inactive C-peptide. Injectable
insulin preparations are purified to remove Cpeptide. Furthermore, injected insulin elevates
immunoreactive serum insulin levels and suppresses
pancreatic secretion of endogenous insulin and Cpeptide. That is, although exogenous insulin elevates
serum insulin levels, C-peptide levels are either
unaffected or decreased. C-peptide determinations
may be carried out to augment or confirm results of
serum insulin measurements.59

THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis and sent
promptly to the laboratory. The sample also can be
tested for insulin measurement.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume usual diet.

GLUCAGON
Glucagon is secreted by the cells of the islets of
Langerhans in response to decreased blood glucose
levels. Its actions are opposed by insulin. Elevated
glucagon levels are associated with conditions that
produce actual hypoglycemia or a physiological
need for greater blood glucose (e.g., trauma, infection, starvation, excessive exercise) and with insulin
lack. Thus, elevated glucagon levels may be found in
severe or uncontrolled diabetes mellitus, despite
hyperglycemia.
Reference Values

Reference Values
Conventional Units
0.9–4.2 ng/mL

SI Units
0.30–1.39 nmol/L

Conventional Units
50–200 pg/mL

SI Units
50–200 ng/L

190

SECTION I—Laboratory

Tests

INTERFERING FACTORS

Trauma, infection, starvation, and excessive exercise may lead to elevated levels, as will acute
pancreatitis, pheochromocytoma, uncontrolled
diabetes mellitus, and uremia.
Failure to follow dietary restrictions before the
test may lead to falsely decreased levels.
INDICATIONS FOR GLUCAGON DETERMINATION

Suspected glucagonoma as indicated by elevated
levels (as high as 1000 pg/mL) in the absence of
diabetic ketoacidosis, uremia, pheochromocytoma, or acute pancreatitis
Confirmation of glucagon deficiency related to
loss of pancreatic tissue as a result of chronic
pancreatitis, pancreatic neoplasm, or surgical
resection (Arginine infusion, which normally
leads to elevated glucagon levels, may be used for
further confirmation of the deficiency state.)
Suspected renal transplant rejection, as indicated
by rising plasma glucagon levels (Glucagon levels
may rise markedly several days before serum creatinine begins to rise.)
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
test involving collection of a peripheral blood
sample (see Appendix I).
For this test, the client should fast from foods for
8 hours before the study. Water is permitted.
THE PROCEDURE

A venipuncture is performed and the sample is
collected in either a green- or a lavender-topped
tube, depending on the laboratory performing the
test. The sample should be handled gently to avoid
hemolysis and sent to the laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of a
peripheral blood sample.
Resume usual diet as soon as possible after the
sample has been obtained.
Complications and precautions: Assess the test
results in relation to insulin and glucose levels.

Gastric and Intestinal Hormones
The stomach and intestine secrete various enzymes
and hormones that aid in the digestive process. The
hormones secreted include gastrin, cholecystokinin,
secretin, and gastric inhibitory peptide (GIP). Of
these, only gastrin is currently of diagnostic significance.

Gastrin is secreted by the gastrin cells (G cells) of
the gastric antrum, the pylorus, and the proximal
duodenum in response to vagal stimulation and the
presence of food (especially protein) in the stomach.
Gastrin stimulates the secretion of acidic gastric
juice and pepsin and the release of pancreatic
enzymes. It also stimulates motor activities of the
stomach and intestine, increases pyloric relaxation,
constricts the gastroesophageal sphincter, and
promotes the release of insulin.
Cholecystokinin is secreted by the duodenal
mucosa in response to the presence of fats. It
opposes the actions of gastrin, stimulates contraction of the gallbladder, relaxes the sphincter of Oddi,
and with secretin, controls pancreatic secretions.
Secretin is secreted by the duodenal mucosa in
response to the presence of peptides and acids in the
duodenum. It also opposes the actions of gastrin,
and with cholecystokinin, controls pancreatic secretions. GIP inhibits gastric motility and secretion and
stimulates secretion of insulin.

GASTRIN
Measurement of serum gastrin levels, which is
accomplished through radioimmunoassay techniques, is indicated when disorders producing
elevated levels are suspected. Excessive gastrin secretion occurs because of normal feedback mechanisms
in disorders associated with decreased gastric acid
production as a result of cellular destruction or
atrophy (e.g., gastric carcinoma and age-related
changes in gastric acid secretion). Elevated levels
also may be seen in gastric and duodenal ulcers, in
which gastric acid secretion is actually normal or
low; pernicious anemia; uremia; and chronic gastritis. Decreased gastrin levels are associated with
true gastric hyperacidity as may occur with stress
ulcers.
Both protein ingestion and calcium infusions
elevate serum gastrin levels in certain situations.
Thus, these substances can be used to provoke
gastrin secretion when a single serum determination
is inconclusive. In the secretagogue provocation test,
a fasting serum gastrin sample is drawn and the
client is then given a high-protein test meal. A postprandial blood sample is then obtained. In individuals with duodenal or gastric ulcers, gastrin levels will
be markedly higher than in normal persons after
protein-stimulated gastrin secretion. Likewise, an
infusion of calcium gluconate produces elevated
serum gastrin levels in a person with gastrinoma
caused by gastrin production by tumor cells. This
effect is not seen in individuals with peptic ulcer
disease.

CHAPTER 5—Blood

Chemistry

191

ELECTROLYTES

Reference Values
Conventional Units

SI Units

Fasting

50–150 pg/mL

50–150 ng/L

Postprandial

80–170 pg/mL

80–170 ng/L

Note: Postprandial values may vary according to the test
method used.
INTERFERING FACTORS

Protein ingestion and calcium infusions will
elevate serum gastrin levels in some situations;
these substances may be used for “challenge tests”
of gastrin secretion.
INDICATIONS FOR SERUM GASTRIN TEST

Suspected
gastrinoma
(Zollinger-Ellison
syndrome) as indicated by markedly elevated
levels (e.g., greater than 1000 pg/mL) and by
marked response to calcium challenge
Support for diagnosing gastric carcinoma, pernicious anemia, or G-cell hyperplasia as indicated
by elevated levels
Differential diagnosis of peptic ulcer disease from
other disorders, because gastrin levels may be
normal but will rise in response to protein challenge
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
test involving collection of a peripheral blood
sample (see Appendix I).
For this test, the client should fast from food for
12 hours before the study. Water is not restricted.
It also is recommended that medications be withheld for 12 to 24 hours before the test, although
this practice should be confirmed with the person
ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be packed in ice, handled gently to avoid hemolysis,
and transported immediately to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of a
peripheral blood sample.
Resume usual diet and medications.
Complications and precautions: Assess bowel
sounds if levels are increased to 100 to 500 pg/mL,
which indicates Zollinger-Ellison syndrome associated with peptic ulcer disease.

Electrolytes are substances that dissociate into electrically charged ions when dissolved. Cations carry
positive charges and anions carry negative charges.
Both affect the electrical and osmolal (i.e., the
number of particles dissolved in a fluid) functioning
of the body. Body fluids always contain equal
numbers of positive and negative charges, but the
nature of the ions, the number of charges present on
a single molecule, and the nature and mobility of the
charged molecules differ enormously among body
fluid compartments (e.g., intracellular versus extracellular).
Not all charged particles are ions. Proteins, for
example, carry a net negative charge. Whenever fluid
contains protein, there must be accompanying
cations. Similarly, not all solutes found in plasma are
ions. Urea and glucose, for example, do not dissociate; they do not contribute to electrical activity of
fluids and membranes, and they contribute only
moderately to plasma osmolality.
Electrolyte quantities and the balance among
them in the body fluid compartments are controlled
by (1) oxygen and carbon dioxide exchange in the
lungs; (2) absorption, secretion, and excretion of
many substances by the kidneys; and (3) secretion of
regulatory hormones by the endocrine glands.
Quantitatively, the most important body fluid
ions are sodium, potassium, chloride, and bicarbonate. These ions are measured in routine serum electrolyte determinations. Other serum ions that may
be measured include calcium, magnesium, and
phosphorus.60

SERUM SODIUM
Sodium (Na, Na ) is the most abundant cation in
extracellular fluid and, along with its accompanying
chloride and bicarbonate anions, accounts for 92
percent of serum osmolality. Sodium plays a major
role in maintaining homeostasis through a variety of
functions, which include (1) maintenance of
osmotic pressure of extracellular fluid, (2) regulation of renal retention and excretion of water, (3)
maintenance of acid–base balance, (4) regulation of
potassium and chloride levels, (5) stimulation of
neuromuscular reactions, and (6) maintenance of
systemic blood pressure. Serum sodium levels may
be affected by a variety of disorders and drugs (Table
5–22) and are evaluated in relation to other serum
electrolyte and blood chemistry results. Tests of
urinary sodium and osmolality also may be necessary for complete interpretation. Note that falsely
decreased serum sodium levels may occur with

192

SECTION I—Laboratory

Tests

Reference Values
Conventional Units

SI Units

Infants

134–150 mEq/L

134–150 mmol/L

Children

135–145 mEq/L

135–145 mmol/L

Adults

135–145 mEq/L

135–145 mmol/L

Critical values

120 mEq/L or 160 mEq/L

120 mmol/L or 160 mmol/L

elevated serum triglyceride levels and myeloma
proteins.
INTERFERING FACTORS

Elevated serum triglyceride levels and myeloma
proteins may lead to falsely decreased levels.
Adrenocorticosteroids, methyldopa, hydralazine,
reserpine, and cough medicines may lead to
increased levels.
Lithium, vasopressin, and diuretics may lead to
decreased levels.
INDICATIONS FOR SERUM SODIUM TEST

Routine electrolyte screening in acute and critical
illness
Determination of whole body stores of sodium,
because the ion is predominantly extracellular
Known or suspected disorder associated with
altered fluid and electrolyte balance (see Table
5–22)
Estimation of serum osmolality, which is
normally 285 to 310 mOsm/kg, by using the
following formula, where BUN stands for blood
urea nitrogen:
Serum osmolality

2(Na )

glucose
20

BUN
3

Note: If the value for serum osmolality is
greater than 2.0 to 2.3 times the value for serum
sodium, then hyperglycemia, uremia, or metabolic acidosis should be suspected.
Evaluation of the effects of drug therapy on serum
sodium levels (e.g., diuretic therapy)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter serum sodium
levels, a medication history should be obtained. It
is recommended that any drugs that may alter test
results be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.

THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Increased levels: Note and report increased levels.
Assess for symptoms associated with hypernatremia, such as fluid deficit with thirst; dry
mucous membranes and skin; poor skin turgor;
or fluid excess with edema, weight gain, or
elevated blood pressure. Administer fluid replacement at an ordered rate and time if the client
is dehydrated or if diuretics are administered
for fluid excess. Instruct client in a low-sodium
diet.
Decreased levels: Note and report decreased
levels. Assess for symptoms associated with
hyponatremia, such as oliguria, rapid pulse,
abdominal cramping, fluid retention, weight gain,
edema, or elevated blood pressure. Administer
ordered sodium replacement via IV or dietary
intake. Instruct client in sodium intake (food, salt
tablets) to replace and maintain sodium, especially if this electrolyte is lost because of vomiting,
diarrhea, perspiration, or use of diuretics.
Critical values: Notify the physician at once of
levels less than 120 mEq/L or greater than 160
mEq/L.

SERUM POTASSIUM
Potassium (K, K ) is the most abundant intracellular cation; much smaller amounts are found in the
blood. Potassium is essential for the transmission of
electrical impulses in cardiac and skeletal muscle. In
addition, it helps to maintain the osmolality and
electroneutrality of cells, functions in enzyme reactions that transform glucose into energy and amino

CHAPTER 5—Blood

TABLE 5–22

•

Chemistry

193

Disorders and Drugs Associated with Altered Serum
Sodium and Extracellular Fluid Levels

Increased Serum Sodium (Hypernatremia)

Decreased Serum Sodium (Hyponatremia)

Total Body Sodium Normal, ECF Volume Low

Total Body Sodium and ECF Volume Low, but Total
Body Sodium Proportionately Lower

Hypovolemia

Addison’s disease

Dehydration

Salt-losing renal disorders

Fever

Gastrointestinal fluid loss (nasogastric suction, vomiting, diarrhea, fistula, paralytic ileus)

Thyrotoxicosis

Diaphoresis

Hyperglycemic hyperosmolar nonketotic
syndrome

Diuresis

Diabetes insipidus

Burns

Hyperventilation

Ascites

Mechanical ventilation without humidification

Massive pleural effusion
Diabetes ketoacidosis

Total Body Sodium Increased Proportionately
More Than ECF Volume

Total Body Sodium Normal and ECF Volume Normal
to High

Excessive salt ingestion

Acute water intoxication

Inappropriate or incorrect intravenous therapy
with fluids containing sodium

Syndrome of inappropriate antidiuretic hormone
secretion

Cushing’s syndrome

Glucocorticoid deficiency

Hyperaldosteronism

Severe total body potassium depletion

Total Body Sodium Low with ECF Volume
Proportionately Lower

Total Body Sodium and ECF Volume Increased, but
ECF Proportionately Greater

Gastroenteritis

Acute renal failure with water overload

Osmotic diuresis

Congestive heart failure

Diaphoresis

Cirrhosis
Nephrotic syndrome

Drugs

Adrenocorticosteroids

Lithium carbonate

Methyldopa (Aldomet)

Vasopressin

Hydralazine (Apresoline)

Diuretics (thiazides, mannitol, ethacrynic acid,
furosemide)

Reserpine (Serpasil)
Cough medicines
Adapted from Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 11.
FA Davis, Philadelphia, 2000, p 401, with permission.

acids into proteins, and participates in the maintenance of acid–base balance.
Numerous disorders and drugs can affect serum
potassium levels. As shown in Table 5–23, the clinical problems associated with altered serum potas-

sium levels may be categorized as (1) inappropriate
cellular metabolism, (2) altered renal excretion, and
(3) altered potassium intake. False elevations in
serum potassium can occur with vigorous pumping
of the hand after tourniquet application for

194

SECTION I—Laboratory

Tests

venipuncture, in hemolyzed samples, or with high
platelet counts during clotting. Falsely decreased
levels are seen in anticoagulated samples left at room
temperature.
Altered serum potassium levels are of particular
concern because of their effects on cardiac impulse
conduction, especially when the client also is taking
medications that affect cardiac conduction. The
combination of low serum potassium (hypokalemia) and therapy with digitalis preparations, for
example, can produce serious consequences because
of increased ventricular irritability.
Note also that potassium is a very changeable ion,
moving easily between intracellular and extracellular

TABLE 5–23

•

fluids. An example is seen in states of acidosis and
alkalosis. In acidosis (decreased serum pH), potassium moves from the cells into the blood; in alkalosis (increased serum pH), the reverse occurs.
INTERFERING FACTORS

False elevations may occur with vigorous pumping of the hand after tourniquet application for
venipuncture, in hemolyzed samples, or with high
platelet counts during clotting.
Falsely decreased levels are seen in anticoagulated
samples left at room temperature.
Numerous drugs may produce elevated and
decreased levels (see Table 5–23).

Disorders and Drugs Associated with Altered Serum
Potassium Levels

Increased Serum Potassium (Hyperkalemia)

Decreased Serum Potassium (Hypokalemia)

Inappropriate Cellular Metabolism

Acidosis

Alkalosis

Insulin deficiency

Insulin excess

Hypoaldosteronism

Familial periodic paralysis

Cell necrosis (trauma, burns, hemolysis,
antineoplastic therapy)

Rapid cell generation (leukemia, treated
megaloblastic anemia)

Addison’s disease

Chronic excessive licorice ingestion

Decreased Renal Excretion

Increased Excretion

Acute renal failure

Gastrointestinal loss (vomiting, diarrhea,
nasogastric suction, fistula)

Chronic interstitial nephritis

Excessive diuresis

Tubular unresponsiveness to aldosterone

Hyperaldosteronism

Hypoaldosteronism

Laxative abuse
Hypomagnesemia
Renal tubular acidosis
Diaphoresis
Thyrotoxicosis
Cushing’s syndrome

Increased Potassium Intake

Decreased Potassium Intake

Salt substitutes

Anorexia nervosa

Potassium supplements (oral or IV)

Diet deficient in meat and vegetables

Potassium salts of antibiotics

Clay eating (binds potassium and prevents absorption)

Transfusion of old banked blood
IV therapy with inadequate potassium
supplementation

CHAPTER 5—Blood

TABLE 5–23

•

Chemistry

195

Disorders and Drugs Associated with Altered Serum
Potassium Levels

Increased Serum Potassium (Hyperkalemia)

Decreased Serum Potassium (Hypokalemia)

Drugs

Aldosterone antagonists

Furosemide

Potassium preparations of antibiotics

Ethacrynic acid

Amphotericin B

Thiazide diuretics

Tetracycline

Insulin

Heparin

Aspirin

Epinephrine

Prednisone

Marijuana

Cortisone

Isoniazid

Gentamicin
Polymyxin B
Lithium carbonate
Sodium polystyrene sulfonate (Kayexalate)
Ammonium chloride
Aldosterone
Laxatives

Adapted from Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 11. FA
Davis, Philadelphia, 2000, p. 402, with Permission.

Reference Values
Conventional Units

SI Units

Infants

4.1–5.3 mEq/L

4.1–5.3 mmol/L

Children

3.4–4.7 mEq/L

3.4–4.7 mmol/L

Adults

3.5–5.0 mEq/L

3.5–5.0 mmol/L

Critical values

2.5 mEq/L or 6.5 mEq/L

2.5 mmol/L or 6.5 mmol/L

INDICATIONS FOR SERUM POTASSIUM TEST

Routine electrolyte screening in acute and critical
illness
Known or suspected disorder associated with
altered fluid and electrolyte balance, especially
renal disease, disorders of glucose metabolism,
trauma, and burns (see Table 5–23)
Known or suspected acidosis of any etiology,
because potassium moves from the cells into the
blood in acidotic states
Evaluation of cardiac dysrhythmias to determine
whether altered serum potassium level is
contributing to the problem (e.g., the combination of low serum potassium and therapy with

digitalis preparations may lead to ventricular irritability)
Evaluation of the effects of drug therapy (e.g.,
diuretics) on serum potassium levels
Evaluation of response to treatment for abnormal
serum potassium levels
Nursing Alert

Because of the effects of serum potassium
levels on cardiac impulse conduction, abnormal values should be reported to the physician immediately so that treatment may be
instituted.

196

SECTION I—Laboratory

Tests

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter serum potassium
levels, a medication history should be obtained. It
is recommended that drugs that may alter test
results be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. Vigorous pumping of
the hand after tourniquet application should be
avoided, because it may lead to falsely elevated
results. The sample should be handled gently to avoid
hemolysis, which may also falsely elevate results, and
transported immediately to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the
test.
Increased levels: Note and report increased levels.
Assess for symptoms associated with hyperkalemia such as oliguria, irritability, diarrhea, and
ECG tracings for peaked T waves. Assess results of
arterial blood gases (ABGs). Prepare client for IV
administration of medications (sodium bicarbonate for acidosis, calcium gluconate if calcium level
is low) or oral or enema administration of sodium
polystyrene sulfonate. Instruct client in low potassium dietary intake and food restrictions (citrus
juices, bananas, dried fruits, potatoes, and tomatoes).
Decreased levels: Note and report decreased
levels. Assess for symptoms of hypokalemia such
as thirst, vomiting, anorexia, weak pulse, decreased
blood pressure, ECG tracings for depressed T
waves, or prominent U waves. Administer oral or
IV potassium replacement. Instruct client in foods
high in potassium, as already listed.
Critical values: Notify the physician at once of
levels less than 2.5 mEq/L or greater than 6.5
mEq/L (greater than 8.1 mEq/L in infants).

SERUM CHLORIDE
Chloride (Cl, Cl2) is the most abundant anion in
extracellular fluid. It participates with sodium in
the maintenance of water balance and aids in the

regulation of osmotic pressure. It also contributes
to gastric acid (HCl) for digestion and for activation of enzymes. Its most important function is
in the maintenance of acid–base balance. In certain
forms of metabolic acidosis, for example, serum
chloride levels may rise in response to decreased
serum bicarbonate levels; this condition is known
as hyperchloremic acidosis. If bicarbonate levels
fall and serum chloride concentration remains
relatively normal, however, a gap between measured cations (i.e., sodium and potassium) and
measured anions (i.e., chloride and bicarbonate)
occurs. This condition often is called anion gap
acidosis (see also section titled “Anion Gap,” which
follows).
Chloride also helps to maintain acid–base balance
through the chloride-bicarbonate shift mechanism,
in which chloride ions enter red blood cells in
exchange for bicarbonate. Bicarbonate leaves the red
blood cells in response to carbon dioxide, which is
released from the tissues into venous blood and
absorbed into the red blood cells. The carbon dioxide is subsequently converted into carbonic acid,
which dissociates into bicarbonate and hydrogen
ions. When the bicarbonate concentration in the red
blood cells exceeds that of the plasma, bicarbonate
diffuses into the blood, and chloride enters the red
blood cells to supply the anions necessary for electroneutrality. For this reason, the chloride content of
red blood cells in venous blood is slightly higher
than that of arterial red blood cells.
Numerous disorders and drugs may alter serum
chloride levels (Table 5–24).
INTERFERING FACTORS

Drugs such as potassium chloride, ammonium
chloride, acetazolamide (Diamox), methyldopa
(Aldomet), diazoxide (Hyperstat), and guanethidine (Ismelin) may lead to elevated levels.
Drugs such as ethacrynic acid (Edecrin),
furosemide (Lasix), thiazide diuretics, and bicarbonate may lead to decreased levels.
INDICATIONS FOR SERUM CHLORIDE TEST

Routine electrolyte screening in acute and critical
illness
Known or suspected disorder associated with
altered acid–base or fluid and electrolyte balance,
or both conditions
Support for diagnosing disorders associated with
altered serum chloride levels (see Table 5–24)
Differentiation of the type of acidosis (hyperchloremic versus anion gap acidosis), with serum
chloride levels remaining relatively normal in
anion gap acidosis

CHAPTER 5—Blood

TABLE 5–24

•

Chemistry

197

Disorders and Drugs Associated with Altered Serum
Chloride Levels

Increased Serum Chloride (Hyperchloremia)

Decreased Serum Chloride (Hypochloremia)
DISORDERS

Acidosis

Alkalosis

Hyperkalemia

Hypokalemia

Hypernatremia

Hyponatremia

Dehydration

Gastrointestinal loss (vomiting, diarrhea, nasogastric
suction, fistula)

Eclampsia
Renal failure (severe)

Diuresis

Congestive heart failure

Hypoventilation (especially due to chronic obstructive
pulmonary disease)

Hyperventilation (especially due to
neurogenic hyperventilation related
to head injury)

Acute infections

Cushing’s syndrome

Burns

Hyperaldosteronism

Heat stroke

Anemia

Fever

Hypoproteinemia

Diabetic ketoacidosis

Serum sickness

Pyelonephritis

Hyperparathyroidism

Addisonian crisis

Excessive dietary salt

Starvation

Jejunoileal bypass

Inadequate chloride intake

Gastric carcinoma
DRUGS

Potassium chloride

Ethacrynic acid (Edecrin)

Ammonium chloride

Furosemide (Lasix)

Acetazolamide (Diamox)

Thiazide diuretics

Methyldopa (Aldomet)

Bicarbonate

Diazoxide (Hyperstat)
Guanethidine (Ismelin)

Reference Values
Conventional Units

SI Units

Newborns

94–112 mEq/L

94–112 mmol/L

Infants

95–110 mEq/L

95–110 mmol/L

Children

98–105 mEq/L

98–105 mmol/L

Adults

95–105 mEq/L

95–105 mmol/L

Critical values

80 mEq/L or 115 mEq/L 80 mmol/L or 115 mmol/L

198

SECTION I—Laboratory

Tests

Evaluation of the effects of drug therapy on serum
chloride levels (see Table 5–24)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter serum chloride
levels, a medication history should be obtained. It
is recommended that those drugs that may alter
test results be withheld for 12 to 24 hours before
the test, although this practice should be
confirmed with the person ordering the study.

kidneys regulate both the generation of bicarbonate
ions and their rate of urinary excretion. Bicarbonate
also participates with chloride in the bicarbonatechloride shift mechanism involving red blood cells.
Measurement of serum bicarbonate ion concentration may be made directly or indirectly by means
of total CO2 content, because more than 90 percent
of blood CO2 exists in the ionized bicarbonate form.
Bicarbonate also is measured as part of blood gas
determinations. Numerous disorders, especially
those involving acid–base imbalance, and drugs are
associated with altered serum bicarbonate levels
(Table 5–25).

THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Increased levels: Note and report increased levels
(hyperchloremia) in relation to increased sodium
and decreased bicarbonate, and assess for changes
in chloride caused by or resulting in metabolic
acidosis.
Decreased levels: Note and report decreased
levels (hypochloremia). Assess for possible cause
(vomiting, gastric suction, diarrhea, diuretic
medication regimen, chronic lung disease,
increased bicarbonate and decreased potassium
resulting in metabolic alkalosis).
Critical values: Notify the physician at once of
levels less than 80 mEq/L or greater than 115
mEq/L.

SERUM BICARBONATE
Bicarbonate (HCO3, HCO3–) is the major extracellular buffer in the blood; it functions with carbonic
acid (H2CO3) in maintaining acid–base balance.
Normally, the ratio of bicarbonate to dissolved
carbon dioxide (CO2), which derives from H2CO3, is
20:1. If this ratio is altered, acid–base imbalance
occurs. Additional CO2, for example, causes
increased acidity (falling pH), whereas loss of CO2
produces alkalinity (rising pH). Similarly, additional
bicarbonate leads to alkalosis, whereas loss of bicarbonate produces acidosis.
The lungs control regulation of CO2 levels.
Bicarbonate levels are under renal control; the

ANION GAP
The results of serum levels of sodium, potassium,
chloride, and bicarbonate may be used to calculate
the anion gap. The anion gap refers to the normal
discrepancy between unmeasured (i.e., those not
routinely measured) cations and anions in the
blood. Unmeasured anions include the negative
charges contributed by serum proteins and those
of phosphates, sulfates, and other metabolites.
Unmeasured anions normally total about 24 mEq/L.
Cations not routinely measured include calcium and
magnesium, and together they account for about 7
mEq/L. Because there are normally more unmeasured anions than cations, the difference between
the two is called the anion gap. This is normally 12
to 18 mEq/L.
The anion gap can be determined by subtracting
the sum of routinely measured anions, chloride and
bicarbonate, from the sum of routinely measured
cations, sodium and potassium (i.e., [Na K] – [Cl
HCO3]). The concept of anion gap allows consideration of metabolic derangements without measuring specific metabolites. An increase in the anion gap
is seen in acidotic states in which there is no
compensatory rise in chloride levels. Examples of
anion gap acidosis include diabetic ketoacidosis,
lactic acidosis caused by either tissue hypoxia (type
A) or renal or hepatic metabolic defect (type B), and
excessive alcohol ingestion.61
INTERFERING FACTORS

Numerous drugs may alter serum bicarbonate
levels (see Table 5–25).
INDICATIONS FOR SERUM BICARBONATE TEST

Routine electrolyte screening in acute and critical
illness
Known or suspected disorder associated with
altered acid–base or fluid and electrolyte balance,
or both

CHAPTER 5—Blood

TABLE 5–25

•

Chemistry

199

Disorders and Drugs Associated with Altered Serum
Bicarbonate Levels

Increased Serum Bicarbonate

Decreased Serum Bicarbonate
DISORDERS

Metabolic alkalosis

Metabolic acidosis

Compensated metabolic alkalosis

Compensated metabolic acidosis

Respiratory acidosis (slightly elevated or normal)

Respiratory alkalosis (slightly low or normal)

Compensated respiratory acidosis

Compensated respiratory alkalosis

Hypoventilation

Hyperventilation

Chronic obstructive pulmonary disease

Diarrhea

Vomiting

Dehydration

Nasogastric suction

Severe malnutrition

Diuresis

Burns

Aldosteronism

Myocardial infarction

Congestive heart failure

Acute ethanol intoxication

Hypokalemia

Shock

Cushing’s syndrome

Renal disease

Pulmonary edema

Hyperthyroidism

Milk-alkali syndrome
DRUGS

Aldosterone

Triamterene (Dyrenium)

Adrenocorticotropic hormone

Acetazolamide (Diamox)

Sodium bicarbonate abuse

Calcium chloride

Adrenocorticosteroids

Ammonium chloride

Viomycin

Salicylate toxicity

Thiazide diuretics

Paraldehyde
Sodium citrate

Reference Values
Conventional Units

SI Units

Peripheral vein

19–25 mEq/L

19–25 mmol/L

Arterial sample

22–26 mEq/L

22–26 mmol/L

Critical values

15 mEq/L or 35 mEq/L

15 mmol/L or 35 mmol/L

Support for diagnosing disorders associated with
altered serum bicarbonate levels (see Table 5–25)
Determination of the degree of compensation in
acidotic and alkalotic states (Table 5–26)
Evaluation of the effects of drug therapy on serum
bicarbonate levels

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter serum bicarbonate

200

SECTION I—Laboratory

Tests

TABLE 5–26

•

Blood Gases in Acid–Base Imbalance
pH

pCO2

HCO3

Base Excess (BE)

↓

↑

Normal

Sl ↓ or normal

↑

Normal

↓

Normal

↓

Sl ↓ or normal

↓

↑

Normal

↑

Sl ↑ or normal

↑

↓

↑

↓

Respiratory acidosis with compensation

↑

Respiratory alkalosis with compensation

Sl ↑ or normal

↓
↓

↓

Metabolic acidosis with compensation

Metabolic alkalosis with compensation

Mixed respiratory and metabolic acidosis
Sl

slightly.

levels, a medication history should be obtained. It
is recommended that drugs that may alter test
results be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Increased levels: Note and report increased levels
or base excess in relation to hypokalemia and
hypochloremia. Assess for vomiting, presence of
gastric suctioning, diuretic therapy, or excessive
intake of oral bicarbonate (baking soda, antacids).
Assess for respiratory changes, tingling in fingers,
or more severe muscular irritability symptoms.
Assess for cardiac dysrhythmias if hypokalemia is
present. Administer ordered oral or IV electrolyte
replacement (potassium, chloride). Administer
fluids (juices, broth) to replace electrolytes if
decreases are not extreme.
Decreased levels: Note and report decreased
levels or base deficit in relation to other electrolytes. Assess gastrointestinal losses such as
vomiting leading to acidosis and diarrhea leading
to alkalosis, I&O, metabolic acidosis with change
in respirations (Kussmaul’s breathing), confusion,

or lethargy. Prepare for IV sodium bicarbonate.
Monitor I&O closely to prevent fluid and electrolyte imbalance.
Critical values: Notify the physician at once of
levels less than 15 mEq/L or greater than 35
mEq/L.

SERUM CALCIUM
Calcium (Ca, Ca ) is the most abundant cation in
the body and participates in virtually all vital
processes. About half the total amount of calcium
circulates as free ions that participate in blood coagulation, neuromuscular conduction, intracellular
regulation, glandular secretion, and control of skeletal and cardiac muscle contractility. The remaining
calcium is bound to circulating proteins and plays
no physiological role. Serum calcium measurement
includes both ionized and protein-bound calcium.
Calcium ions undergo continuous turnover, with
bone serving as the major reservoir. Serum contains
only a small amount at any one time, but the serum
level reflects overall calcium metabolism. Calcium
levels are largely regulated by the parathyroid glands
and vitamin D. Other substances affecting calcium
levels include estrogens and androgens, calcitonin,
and ingested carbohydrates. Increased or decreased
serum proteins also may affect levels of proteinbound calcium.62
Table 5–27 shows the various disorders and drugs
associated with altered calcium levels. Abnormal
serum calcium may produce cardiac dysrhythmias.
Furthermore, serum calcium levels have a reciprocal
relationship with serum phosphate levels; if one
rises, the other tends to fall.

CHAPTER 5—Blood

TABLE 5–27

•

Chemistry

201

Disorders and Drugs Associated with Altered Serum
Calcium Levels

Increased Levels (Hypercalcemia)

Decreased Levels (Hypocalcemia)
DISORDERS

Acidosis

Alkalosis

Hyperparathyroidism

Hypoparathyroidism

Cancers involving bone

Pseudohypoparathyroidism

Paget’s disease of bone

Inadequate dietary intake of calcium and/or vitamin D

Prolonged immobility

Vitamin D–resistant rickets

Leukemia

Malabsorption syndromes

Multiple myeloma

Hypoproteinemia

Lymphomas

Laxative abuse

Hyperproteinemia

Acute pancreatitis

Polycythemia vera

Burns

Bone growth or active bone formation

Osteomalacia

Vitamin D intoxication

Peritonitis

Hyperthyroidism (severe)

Pregnancy

Milk-alkali syndrome

Overwhelming infections
Hypomagnesemia
Renal failure
Phosphate excess
DRUGS

Thiazide diuretics

Barbiturates

Hormones (androgens, progestins, estrogens)

Anticonvulsants

Vitamin D

Acetazolamide (Diamox)

Calcium supplements

Adrenocorticosteroids
Cytotoxic drugs

INTERFERING FACTORS

Values are higher in children because of growth
and active bone formation.
Numerous drugs may alter serum calcium levels
(see Table 5–27).
Increased or decreased serum protein levels may
alter results.
INDICATIONS FOR SERUM CALCIUM TEST

Evaluation of the effects of various disorders on
overall calcium metabolism, especially diseases
involving bone (see Table 5–27)
Detection of parathyroid gland loss after thyroid

or other neck surgery, as indicated by decreased
levels
Monitoring of the effects of renal failure on
calcium levels, which are usually decreased in the
disorder
Evaluation of cardiac dysrhythmias to determine
whether altered serum calcium level is contributing to the problem
Evaluation of coagulation disorders to determine
whether altered serum calcium level is contributing to the problem
Monitoring for the effects of various drugs on
serum calcium levels (see Table 5–27)
Evaluation of the effectiveness of treatment for

202

SECTION I—Laboratory

Tests

Reference Values
Conventional Units
Newborns

SI Units

7.0–11.5 mg/dL

1.75–2.90 mmol/L

3.7–7.0 mEq/L
Infants

8.6–11.2 mg/dL

2.15–2.80 mmol/L

5.0–6.0 mEq/L
Children

12.0 mg/dL

3 mmol/L

6.0 mEq/L
Adults

9–11 mg/dL

2.25–2.75 mmol/L

4.5–5.5 mEq/L
Critical values

6 mg/dL or 13 mg/dL

abnormal calcium levels, especially in deficiency
states
Nursing Alert

Because altered serum calcium levels may
produce cardiac dysrhythmias, abnormal
values should be reported to the physician
immediately so that treatment may be instituted.

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter serum calcium
levels, a medication history should be obtained. It
is recommended that drugs that may alter test
results be withheld for 12 to 24 hours before the
test, although this practice should be confirmed
with the person ordering the study.
THE PROCEDURE

1.5 mmol/L or 3.25 mmol/L

nausea and vomiting, or increased intake of
dietary calcium. Encourage fluid intake. Instruct
client to restrict foods and medications high in
calcium (milk and other dairy foods, eggs, some
antacids).
Decreased levels: Note and report decreased
levels. Assess for symptoms associated with
hypocalcemia such as muscular irritability
(tingling in fingers and around mouth, muscle
cramping or twitching, facial spasm or Chvostek’s
sign, carpopedal spasm or Trousseau’s sign, and
tetany). Instruct client to eat foods and fluids high
in calcium. Administer oral calcium supplement
or replacement; prepare for IV calcium replacement in more severe cases.
Critical values: Notify the physician at once of
levels less than 6 mg/dL or greater than 13
mg/dL.

SERUM PHOSPHORUS/PHOSPHATE
Phosphorus (P), the dominant intracellular anion,
is measured in serum as phosphate (HPO4– –,
H2PO4–). Results are reported as inorganic phosphorus (Pi). Phosphates are vital constituents of
nucleic acids, intracellular energy storage compounds, intermediary compounds in carbohydrate
metabolism, and various regulatory compounds,
including that which modulates dissociation of
oxygen from hemoglobin. Phosphorus also aids in
regulation of calcium levels and functions as a buffer
in the maintenance of acid–base balance. It
contributes to the mineralization of bones and teeth,
promotes renal tubular reabsorption of glucose,
and, as a component of phospholipids, aids in fat
transport.
As with calcium, phosphorus ions undergo
continuous turnover, with bone serving as the major

CHAPTER 5—Blood

TABLE 5–28

•

Chemistry

203

Disorders and Drugs Associated with Altered Serum
Phosphorus/Phosphate

Increased Levels (Hyperphosphatemia)

Decreased Levels (Hypophosphatemia)
DISORDERS

Diabetic ketoacidosis

Recovery phase of diabetic ketoacidosis

Renal failure

Renal tubular acidosis

Vitamin D intoxication

Hypocalcemia

Hypercalcemia

Vitamin D deficiency

Prolonged immobilization

Hyperparathyroidism

Hypoparathyroidism

Carbohydrate ingestion

Pseudohypoparathyroidism

Malnutrition

Bone growth or active bone formation

Malabsorption syndromes

Hyperthyroidism

Hypothyroidism

Acromegaly

Hypopituitarism

Sarcoidosis

Alcoholism

Pyloric obstruction

Prolonged vomiting and diarrhea

Milk-alkali syndrome
DRUGS

Sodium phosphate

Acetazolamide (Diamox)

Heparin

Aluminum hydroxide

Phenytoin (Dilantin)

Insulin

Posterior pituitary injection (Pituitrin)

Epinephrine

Androgens

Reference Values
Conventional Units

SI Units

Infants

4.5–6.7 mg/dL

1.45–2.16 mmol/L

Children

4.5–5.5 mg/dL

1.45–1.78 mmol/L

Adults

2.4–4.7 mg/dL

0.78–1.50 mmol/L

Critical values

1 mg/dL

0.32 mmol/L

Note: Phosphorus is measured in terms of phosphate; the results cannot
be expressed in milliequivalents because different phosphate groups
have different valences.

reservoir. Serum contains a relatively small amount
of phosphorus at any given time. Phosphorus levels
are largely regulated by the parathyroid glands and
vitamin D, and they are normally reciprocal to those
of serum calcium. The equilibrium between serum
phosphate levels and intracellular stores is affected
by carbohydrate metabolism and blood pH. When
persons with diabetic ketoacidosis are treated with

insulin, for example, phosphate enters the cells along
with glucose and potassium. Phosphate excretion is
controlled by the kidneys. Disorders and drugs associated with altered phosphorus levels are listed in
Table 5–28. Note that several disorders associated
with decreased phosphorus levels are the same as
those causing elevated serum calcium levels (e.g.,
hyperparathyroidism).

204

SECTION I—Laboratory

Tests

INTERFERING FACTORS

Phosphate levels are higher in children because of
bone growth and active bone formation.
Values vary diurnally, being higher at night than
in the morning.
A number of drugs may alter serum phosphate
levels (see Table 5–28).
Hemolysis of the sample may cause falsely
elevated values resulting from release of phosphate from red blood cells.
INDICATIONS FOR SERUM
PHOSPHORUS/PHOSPHATE TEST

Support for diagnosing disorders associated with
altered phosphorus/phosphate levels, especially
bone disorders, parathyroid disorders, renal
disease, and alcoholism (see Table 5–28)
Monitoring of the effects of renal failure on phosphorus levels, which are usually increased in the
disorder
Support for identification of the cause of growth
abnormalities in children
Monitoring for the effects of various drugs on
serum phosphate levels (see Table 5–28)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Because many drugs may alter serum phosphorus/phosphate levels, a medication history should
be obtained. It is recommended that any drugs
that may alter test results be withheld for 12 to 24
hours before the test, although this practice should
be confirmed with the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis, which may
falsely elevate levels, and transported promptly to
the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Increased levels: Note and report increased levels
(hyperphosphatemia) and associated calcium
levels. Instruct client to avoid foods high in phosphorus (milk and dairy products, poultry, fish,
grain cereals).
Decreased levels: Note and report decreased

levels (hypophosphatemia) in relation to calcium
levels. Instruct client to include foods and fluids
high in phosphorus, as already listed.
Critical values: Notify the physician at once of
levels less than 1 mg/dL.

SERUM MAGNESIUM
Magnesium (Mg, Mg ) is an essential nutrient
found in bone and muscle. In the blood, magnesium
is most abundant in the red blood cells, with relatively little found in the serum. Magnesium functions in (1) control of sodium, potassium, calcium,
and phosphorus; (2) utilization of carbohydrates,
lipids, and proteins; and (3) activation of enzyme
systems that enable B vitamins to function.
Magnesium also increases intestinal absorption of
calcium and is required for bone and cartilage
formation. It is essential for oxidative phosphorylation, nucleic acid synthesis, and blood clotting.
Magnesium is so abundant in foods that dietary
deficiency is rare. Decreased serum magnesium
levels are seen, however, in chronic alcoholism.
Elevated levels most commonly occur in renal failure. A variety of other disorders and drugs also are
associated with altered magnesium levels (Table
5–29). Altered magnesium levels are associated with
cardiac dysrhythmias, especially decreased levels,
which may lead to excessive ventricular irritability.
INTERFERING FACTORS

A number of drugs may alter serum magnesium
levels (see Table 5–29).
Because magnesium is found in red blood cells,
hemolysis of the sample may lead to falsely
elevated values.
INDICATIONS FOR SERUM MAGNESIUM TEST

Determination of magnesium balance in renal
failure and chronic alcoholism
Evaluation of known or suspected disorders associated with altered magnesium levels (see Table
5–29)
Evaluation of cardiac dysrhythmias to determine
whether altered serum magnesium level is
contributing to the problem (i.e., decreased
magnesium levels may lead to excessive ventricular irritability)
Monitoring of the effects of various drugs on
serum magnesium levels (see Table 5–29)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).

CHAPTER 5—Blood

TABLE 5–29

•

Chemistry

Disorders and Drugs Associated with Altered Serum
Magnesium Levels

Increased Levels (Hypermagnesemia)

Decreased Levels (Hypomagnesemia)
DISORDERS

Addison’s disease

Hyperaldosteronism

Adrenalectomy

Hypokalemia

Renal failure

Hypocalcemia

Diabetic ketoacidosis

Diabetic ketoacidosis (resolving)

Dehydration

Alcoholism, cirrhosis

Hypothyroidism

Hyperthyroidism

Hyperparathyroidism

Hypoparathyroidism
Acute pancreatitis
Gastrointestinal loss (vomiting, diarrhea,
nasogastric suction, fistula)
Malabsorption syndromes
Malnutrition
Nephrotic syndrome
Toxemia of pregnancy
High-phosphate diet
DRUGS

Antacids and laxatives containing magnesium

Thiazide diuretics

Salicylates

Ethacrynic acid (Edecrin)

Lithium carbonate

Calcium gluconate
Amphotericin B
Neomycin
Insulin
Aldosterone
Ethanol

Reference Values
Conventional Units

SI Units

Newborns

1.4–2.9 mEq/L

0.58–1.19 mmol/L

Children

1.6–2.6 mEq/L

0.65–1.07 mmol/L

Adults

1.5–2.5 mEq/L

0.61–1.03 mmol/L

1.8–3.0 mg/dL

0.74–1.23 mmol/L

1 mg/dL or 4.9 mg/dL

0.41 or 2.02 mmol/L

Critical values

205

206

SECTION I—Laboratory

Tests

Because many drugs may alter serum magnesium
levels, a medication history should be obtained. It
is recommended that those drugs that may alter
test results be withheld for 12 to 24 hours before
the test, although this practice should be
confirmed with the person ordering the study.
THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Increased levels: Note and report increased levels.
Assess for symptoms associated with hypermagnesemia, such as a decrease in muscle activity,
which can affect respiration and lead to respiratory arrest and coma. Instruct client to avoid
foods high in magnesium (meats, fish, whole
grains, green vegetables) and medications
containing magnesium (antacids or laxatives).
Decreased levels: Note and report decreased
levels. Assess for symptoms of hypomagnesemia,
such as weakness, tremors, paresthesia, and tetany,
which can lead to convulsions. Assess for decreases
in potassium, sodium, and calcium. Administer
ordered magnesium replacement. Instruct client
to eat foods high in magnesium, as already listed.
Critical values: Notify the physician at once of
levels less than 1.0 mg/dL or greater than 4.9
mg/dL.

SERUM OSMOLALITY
Osmolality refers to the concentration of solutes in
plasma or serum (particle number) or in urine
(number of particles). Osmolality affects the movement of fluids across body membranes and the
kidney’s ability to concentrate or dilute the urine.

Dehydration causes an increase in osmolality, and
overhydration causes a decrease. Increased osmolality causes an increase in antidiuretic hormone
(ADH) secretion, which results in increased reabsorption of water by the kidneys, increased concentration in urine, and decreased concentration in
serum. This lower concentration in serum osmolality normally reduces ADH secretion, which then
decreases water reabsorption by the kidneys and
excretion of diluted urine. Urine is normally more
concentrated than plasma; the ratio of urine to
serum osmolality ranges from 1:1 to 3:1 in normal
states. A decrease in the 1:1 ratio is seen in fluid overload or in diabetes insipidus, and a ratio that does
not rise above 1.2:1.0 indicates a loss of renal
concentration function.63
Serum osmolality is mostly used to monitor fluid
and electrolyte balance; urine osmolality is used to
monitor the concentrating ability of the kidneys and
fluid and electrolyte balance. Decreased levels in
serum osmolality are seen in fluid excess or overhydration, hyponatremia, and syndrome of inappropriate ADH (SIADH) secretion. Decreased levels in
urine osmolality are seen in diabetes insipidus, excess
fluid intake or overhydration, hypokalemia, hypercalcemia, and severe renal disease. Increased levels in
serum osmolality are seen in dehydration, hypercalcemia, hypernatremia, hyperglycemia, diabetes
insipidus, ketosis, severe renal disease, alcohol ingestion, and mannitol therapy. Increased levels in urine
osmolality are seen in Addison’s disease, SIADH,
hypernatremia, shock or acidotic states, and CHF.
INTERFERING FACTORS

A delay of longer than 10 hours in testing the
specimen can affect test results.
Osmotic diuretics and mineralocorticoids can
affect test results.
Improper technique such as tourniquet in place
for an extended time can cause hemostasis.
INDICATIONS FOR SERUM OSMOLALITY TEST

Screening for alcohol ingestion revealed by
increase in osmolality level as the alcohol level in
the blood is increased

Reference Values
Conventional Units

SI Units

Children

270–290 mOsm/kg

270–290 mmol/kg

Adults

280–300 mOsm/kg

280–300 mmol/kg

Critical values

240 mOsm or 360 mOsm

240 or 360 mmol/kg

CHAPTER 5—Blood

Monitoring fluid and electrolyte balance (especially sodium) and determining a state of dehydration or overhydration
Evaluating ADH secretion or suppression
Monitoring IV fluid replacement therapy to
prevent fluid excess or overload
Evaluating the effect of renal dialysis therapy and
course of renal failure
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Obtain a history of conditions affecting renal
function, a medication regimen, and the results of
an electrolyte panel. Any medications that may
affect test results should be withheld, although
this practice should be confirmed with the person
ordering the study.
Inform the client that a urine specimen can be
collected, tested, and compared with the results of
the blood test.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be handled gently to avoid hemolysis or hemostasis
and transported promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume any medications withheld before the test.
Increased levels: Note and report increased levels.
Assess for symptoms associated with dehydration,
such as thirst, dry skin and mucous membranes,
and poor skin turgor. Assess relationship to urine
osmolality and electrolyte panel. Prepare to
increase fluid intake orally or IV.
Decreased levels: Note and report decreased levels.
Assess for symptoms associated with overhydration such as edema, weight gain, dyspnea, cough,
and venous distention. Assess relationship to urine
osmolality and electrolyte panel. Administer
ordered medications such as diuretic therapy.
Critical values: Notify physician at once of
levels less than 240 mOsm or greater than 360
mOsm.

ARTERIAL BLOOD GASES
Arterial blood gas (ABG) determinations are made
not only to determine levels of actual blood gases
(i.e., oxygen and carbon dioxide) but also to assess

Chemistry

207

the client’s overall acid–base balance. Thus, ABG
levels may indicate hypoxia, hypercapnia or
hypocapnia, acidosis, alkalosis, and physiological
compensation for acid–base imbalance. The components of an ABG determination are as follows:
1. pH reflects the number of hydrogen ions in the
body and is influenced primarily by the ratio
of bicarbonate ions (HCO3–) to carbonic acid
(H2CO3), which is essentially carbon dioxide
(CO2), in the blood. The normal HCO3–-toCO2 ratio is 20:1. When the hydrogen ion
concentration increases (acidosis), the pH
falls; when the hydrogen ion concentration
decreases (alkalosis), the pH rises. Bicarbonate
levels are regulated by the kidneys, whereas
carbon dioxide levels are controlled by the
lungs. Both the lungs and the kidneys respond
to alterations in pH levels by either retaining or
excreting carbon dioxide and bicarbonate,
respectively.
2. pO2 indicates the partial pressure of oxygen in
the blood. When oxygen levels are lower than
normal, the client is hypoxic. Hypoxemia may
be caused by either low cardiac output or
impaired lung function.
3. pCO2 indicates the partial pressure of carbon
dioxide in the blood, which is regulated by the
lungs. Except in cases of compensation for
metabolic acid–base imbalances, elevated
levels (hypercapnia, hypercarbia) indicate
impaired gas exchange in the lungs so that
excess CO2 is not eliminated. Decreased levels
(hypocapnia, hypocarbia) indicate increased
loss of CO2 through the lungs (hyperventilation).
4. HCO3– indicates the bicarbonate ion concentration in the blood, which is regulated by the
kidneys. Altered levels are associated with
metabolic acid–base imbalances or reflect
response to respiratory alterations in CO2
levels.
5. O2 saturation (O2 Sat, SaO2) indicates the
oxygen content of the blood expressed as
percent of oxygen capacity (the amount of
oxygen the blood could carry if all of the
hemoglobin were fully saturated with oxygen).
If the blood is 50 percent saturated, for example, the oxygen content is one-half of the
oxygen capacity.
6. Base excess (BE) usually indicates the difference between the normal serum bicarbonate
(HCO3–) level and the client’s bicarbonate
level. Positive values indicate excess bicarbonate relative to normal values, whereas negative
values indicate decreased HCO3– levels.

208

SECTION I—Laboratory

Tests

Reference Values
Conventional Units

SI Units

pH
Newborns

7.32–7.49

Adults

7.35–7.45

pO2
Newborns

60–70 mm Hg

Adults

75–100 mm Hg

pCO2

35–45 mm Hg

HCO3

–

Newborns

20–26 mEq/L

20–26 mmol/L

Adults

22–26 mEq/L

22–26 mmol/L

O2 saturation

96–100%

Base excess
Critical values
pH
pO2
Infants
Adults
pCO2
HCO3–
O2 saturation

1 to –2
7.2 or 7.6
37 mm Hg or 92 mm Hg
40 mm Hg
20 mm Hg or 70 mm Hg
10 mEq/L or 40 mEq/L
60%

INTERFERING FACTORS

Fever may falsely elevate pO2 and pCO2;
hypothermia may lower them.
Suctioning of respiratory passages within 20 to 30
minutes of the test may alter results. Excessive
heparin in the sample will lower pH and pCO2.
Exposure of the sample to atmospheric air (e.g.,
air bubbles in the sample) may alter results.
Exposure of the sample to room temperature for
more than 2 minutes may alter test results.
INDICATIONS FOR ARTERIAL BLOOD GASES TEST

Evaluation of the effectiveness of pulmonary
ventilation in maintaining adequate oxygenation
and in removing carbon dioxide, especially in
disorders such as chronic pulmonary disease,
neurological insults, and drug intoxication
Evaluation of the effectiveness of cardiac output
in maintaining adequate oxygenation, especially
in shock and acute myocardial infarction
Determination of the need for oxygen therapy
(Oxygen is generally indicated if the pO2 is 70 mm
Hg or less, except in pulmonary disorders charac-

10 mmol or 40 mmol/L

terized by chronic hypoxemia in which lower
oxygen levels may be tolerated by the client without supplemental oxygen.)
Determination of respiratory failure, which is
defined as a pO2 of 50 mm Hg or less with a pCO2
of 50 mm Hg or more
Determination of acid–base balance, type of
imbalance, and degree of compensation (see Table
5–26)
Determination of need for mechanical ventilation
(For example, elevated or rising pCO2 levels may
indicate the need for mechanical ventilation,
especially when pO2 is decreased.)
Evaluation of effectiveness of mechanical ventilation and indication for modification of ventilator
settings
Evaluation of response to weaning from mechanical ventilation
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That repeat determinations may be necessary
until cardiopulmonary function or acid–base
balance, or both, are stabilized

CHAPTER 5—Blood

The method and site for obtaining the sample
(e.g., arterial puncture or arterial line sample)
Any anticipated discomforts (Arterial punctures
cause a brief, sharp pain unless a local anesthetic
is used.)
That if an arterial puncture is performed, it will be
necessary to maintain digital pressure on the
puncture site for 5 minutes or more, after which a
pressure dressing will be applied
Prepare the client for the procedure:
Take the client’s temperature. Fever may falsely
elevate pO2 and pCO2; hypothermia may lower
them.
The client should not have had a respiratory therapy treatment, been suctioned, or had ventilator
settings changed less than 20 to 30 minutes before
the sample is obtained.
If the test is being conducted to determine the
need for oxygen therapy or response to weaning
from mechanical ventilation, the client should be
off oxygen, off mechanical ventilation, or on a
weaning mode for a preset time, which is specified
by the person ordering the test.
If the sample is to be obtained by radial artery
puncture, the Allen test should be performed to
assess patency of the ulnar artery; in the event that
thrombosis involving the radial artery occurs after
the puncture:
Extend the client’s wrist over a rolled towel or
similar support.
Ask the client to clench the fist; if the client
cannot clench the fist, elevate the hand above
heart level.
Apply digital pressure over both radial and
ulnar arteries.
Ask the client to unclench the fist while pressure is maintained on the arteries.
Observe the palm for blanching, which is the
expected response.
Release pressure on the ulnar artery while
continuing to maintain pressure on the radial
artery.
Observe the palm for returning pinkness,
which is a positive result.
If the palm remains blanched or if return of
pinkness takes longer than approximately 5
seconds (a negative result), do not use the wrist
for arterial punctures.
Inform the client’s physician of a negative
response to the Allen test.
THE PROCEDURE

The procedure varies slightly with the method for
obtaining the sample.

Chemistry

209

Arterial Puncture. A blood gas collection kit is
obtained. If prepackaged kits are not available,
obtain a 3-mL syringe, heparin (usually in the
concentration of 100 U/mL), 20-gauge or 21-gauge
needles, povidone-iodine or alcohol swabs or
sponges, gauze pads, and tape. Fill a plastic or paper
cup or a small plastic bag about halfway with ice.
If the syringe is not preheparinized, draw approximately 1 mL of heparin into the syringe, pull the
plunger back to about the 3-mL line, and rotate the
barrel. Then expel all except approximately 0.1 mL
of heparin and change the needle. Excess heparin in
the syringe will lower the pH and pCO2 of the
sample.
Palpate the artery to be used. The radial artery is
usually the most accessible, but the brachial or the
femoral artery also may be used. If the radial artery
is to be used, extend the client’s wrist over a rolled
towel or similar support.
Cleanse the site with povidone-iodine and allow
to dry. It is recommended by some that the iodine
solution be removed with an alcohol swab before
arterial puncture. If the client is allergic to iodine,
use only alcohol to prepare the site. Some authorities also advocate anesthetizing the puncture site
with a small amount of 1 percent lidocaine (Xylocaine).
Using the heparinized syringe with needle
attached, puncture the artery. A 45-degree angle is
used for radial artery punctures; a 60- to 90-degree
angle is used for brachial arteries. A 90-degree angle
is generally used for femoral artery punctures.
Advance the needle until blood begins to enter the
syringe; it should not be necessary to pull back on
the plunger. After 2 to 3 mL of blood have been
obtained, withdraw the needle and immediately
apply firm pressure to the puncture site with a sterile gauze pad. Inform the client that the discomfort
felt after the puncture will disappear in a few
minutes.
Meanwhile, expel any air or air bubbles from the
syringe, because mixing with atmospheric air may
alter test results. The needle may be plugged by
inserting it into a rubber cap, or it may be removed
and the rubber cap supplied in the blood gas collection kit placed on the hub of the syringe. The sample
is then placed in ice to inhibit metabolic blood activity; failure to do this within 2 minutes of collecting
the sample will alter test results.
The sample is sent immediately for analysis.
On the ABG request form or sample label, note
the time the sample was collected, the client’s
temperature, and whether the client was breathing
room air, receiving oxygen, or using mechanical
ventilation.

210

SECTION I—Laboratory

Tests

Arterial Line Sample. See Appendix I, the section
titled “Indwelling Devices and Atrial Venous
Catheters.”
NURSING CARE AFTER THE PROCEDURE

For arterial punctures, maintain digital pressure
on the site for 5 minutes and then apply a sterile
pressure dressing. If the client is receiving anticoagulants or has bleeding tendencies, apply digital
pressure for 10 to 15 minutes.
Observe the arterial puncture site for bleeding or
hematoma formation every 5 to 10 minutes for
one-half hour after the pressure dressing is
applied.
Check for presence of pulses distal to the site
when performing site observations, if the brachial
or the femoral artery was used.
Check for signs of nerve impairment distal to the
site.
Provide support when test findings are revealed
and if repeated or serial testing is necessary in
acute conditions.
Evaluate the results of pH with electrolytes
(particularly hypokalemia or hyperkalemia) and
oxygen, carbon dioxide, and bicarbonate associated with respiratory or metabolic acidosis or
alkalosis.
Assess respiratory pattern, level of consciousness,
neuromuscular irritability, fluid and electrolyte
imbalances, and symptoms of impaired tissue
perfusion as a result of hypoxia, any of which can
be associated with abnormal ABGs.
Notify physician at once of critical lab values.

VITAMINS AND TRACE
MINERALS
Vitamins are essential organic substances that
perform various metabolic functions. Vitamins
cannot be synthesized in adequate amounts by the
body and, therefore, inadequate dietary intake
causes deficiency diseases. Vitamins are classified as
fat soluble and water soluble. The fat-soluble vitamins are vitamins A, D, E, and K. Because they are
stored in the body, excessive ingestion of exogenous
fat-soluble vitamins may cause abnormally elevated
levels. Vitamin C and the B-complex vitamins are
water soluble and are not stored in the body. The Bcomplex vitamins include B1 (thiamine), which is
involved in carbohydrate metabolism; B2 (riboflavin), which is involved in the transport of
oxidative metabolism and fatty acids; B3 (niacin),
which is involved in the transport of cellular respiration; and B6 (pyridoxine), which is involved as a
cofactor of enzymes and in the conversion of trypto-

phan to nicotinic acid. A vitamin B6 deficiency
causes beriberi, and a vitamin B3 deficiency causes
pellagra.
For diagnostic purposes, blood levels of vitamins
A and C and a metabolite of vitamin D are measured. Vitamin B12 and folic acid also are measured in
studies pertaining to hematologic function (see
Chapter 1).

VITAMIN A
Vitamin A is obtained from foods of animal origin,
such as eggs, milk, butter, and liver. Its precursor,
carotene, a yellowish pigment, is obtained from
yellow or orange vegetables and fruits and from leafy
green vegetables.
Vitamin A promotes normal vision by permitting
visual adaptation to light and dark, and it prevents
night blindness (xerophthalmia). It also contributes
to the growth of bone, teeth, and soft tissues;
supports the formation of thyroxine; maintains
epithelial cellular membranes; aids in spermatogenesis; and maintains the integrity of skin and mucous
membranes as barriers to infection.
Reference Values
Conventional Units
Vitamin A 65–275 IU/dL

SI Units
—

0.15–0.60 mg/mL 0.52–2.09 mol/L
Carotene
Infants

0–40 g/dL

0–0.7 mol/L

Children

40–130 g/dL

0.7–2.4 mol/L

Adults

50–300 g/dL

0.9–5.5 mol/L

INTERFERING FACTORS

Pregnancy and oral contraceptive use can lead to
falsely elevated levels, as can hyperlipidemia,
hypercholesterolemia of diabetes, myxedema, and
nephritis.
Excessive ingestion of mineral oil, low-fat diets,
and liver disease may lead to decreased levels.
Failure to follow dietary and drug restrictions
before the test may alter results.
Excessive exposure of the sample to light may alter
results.
INDICATIONS FOR VITAMIN A AND CAROTENE
TEST

Evaluation of skin disorders, with vitamin A deficiency a possible cause

CHAPTER 5—Blood

Support for diagnosing xerophthalmia (night
blindness) as indicated by decreased levels
Suspected vitamin A deficiency caused by fat
malabsorption or biliary tract disease
Support for diagnosing excessive vitamin A or
carotene ingestion, or both, as indicated by
elevated blood levels
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
study involving collection of a peripheral blood
sample (see Appendix I).
For this test, the client should fast for 8 hours
before the study. Water is not restricted.
Vitamin supplements containing vitamin A
should be withheld for at least 24 hours before the
test.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should
be covered to protect it from light, which may alter
test results; handled gently to avoid hemolysis; and
sent promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of a
peripheral blood sample.
Resume usual diet.
Vitamin supplements may be resumed pending
test results.
Decreased level: Note and report symptoms of
deficiency or decreased level. Administer ordered
vitamin A supplement orally, and instruct client
to eat foods high in vitamin A to correct deficiency.
Increased level: Note and report symptoms of
excesses or increased level. Discontinue the oral or
topical medication administered for acne or other
skin conditions.

VITAMIN C
Vitamin C (ascorbic acid) functions in many metabolic processes, especially in those related to collagen
formation and the stress response. In addition, vitamin C helps to maintain capillary strength, facilitates the release of iron from ferritin for hemoglobin
formation and red blood cell maturation, and may
maintain the integrity of the amniotic sac.
Elevated vitamin C levels are associated with
excessive intake of the vitamin within 24 hours of
the test. Decreased intake produces scurvy with low
vitamin C levels.

Chemistry

211

Reference Values
Conventional Units

SI Units

Children

0.6–1.6 mg/dL

34–91 mol/L

Adults

0.2–2.0 mg/dL

11–113 mol/L

INTERFERING FACTORS

Excessive intake of vitamin C within 24 hours of
the test will produce elevated levels.
Failure to follow dietary restrictions before the
test may alter results.
INDICATIONS FOR VITAMIN C TEST

Evaluation of the effects of major stressors (e.g.,
pregnancy, major surgery, burns, infections,
malignancies) on vitamin C levels
Evaluation of the effects of malabsorption
syndromes on vitamin C levels
Evaluation of the effectiveness of therapy with
vitamin C in treating deficiency states
NURSING CARE BEFORE THE PROCEDURE

General client preparation is the same as that for any
study involving collection of a peripheral blood
sample (see Appendix I).
For this test, the client should fast from food for 8
hours beforehand.
Vitamin C preparations also should be withheld
for 24 hours before the study.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a black-topped tube. The sample is
handled gently to avoid hemolysis and transported
promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of a
peripheral blood sample.
Resume usual diet.
Vitamin C preparations may be resumed pending
test results.
Decreased level: Note and report symptoms of
deficiency or decreased level such as bleeding and
poor wound healing. Instruct client to eat foods
high in vitamin C to correct deficiency.
Administer oral vitamin C supplement in ordered
dosage.
Increased level: Note and report symptoms of
excesses or increased level. Discontinue the oral
intake to prevent overdose; high doses taken as a
preventive treatment can cause renal calculi.

212

SECTION I—Laboratory

Tests

VITAMIN D
The form of vitamin D most easily and accurately
measured is 25-hydroxy-cholecalciferol [vitamin D3,
25(OH)D3, cholecalciferol], a monohydroxylated
form that leaves the liver for subsequent dihydroxylation by the kidney. Indirect measurement of vitamin D by serum alkaline phosphatase, calcium, and
phosphorus determinations preceded 25(OH)D3
assays and may still be used in the diagnosis of disorders of calcium metabolism.
Vitamin D aids in the maintenance of
calcium–phosphorus balance and in the deposition
of calcium and phosphorus in the bone. It also facilitates absorption of calcium and phosphorus from
the small intestine and aids in the renal excretion of
phosphorus.
Reference Values
Conventional Units

SI Units

25(OH)D3

0.7–3.3 IU/mL

10–55 ng/mL

25–100 pmol/L

INTERFERING FACTORS

Excessive ingestion of vitamin D leads to elevated
levels.
Therapy with anticonvulsants and glucocorticoids
may produce decreased levels.
INDICATIONS FOR VITAMIN D TEST

Differential diagnosis of hypercalcemia caused by
parathyroid adenoma or vitamin D toxicity
Confirmation of vitamin D deficiency as the cause
of bone disease
Confirmation of vitamin D deficiency caused by
malabsorption syndromes, hepatobiliary disease,
and chronic renal failure
Evidence of interference with vitamin D levels as
a result of anticonvulsant or steroid therapy
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any study
involving the collection of a peripheral blood
sample.
It is recommended that anticonvulsant and
steroid medications be withheld for 24 hours
before the test, although this practice should be
confirmed by the person ordering the study.
THE PROCEDURE

A venipuncture is performed and the sample
collected in a red-topped tube. The sample should

be handled gently to avoid hemolysis and transported promptly to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any study involving the collection of a
peripheral blood sample.
Resume medications withheld before the test.
Decreased level: Note and report symptoms of
deficiency or decreased level such as bone deformities. Instruct client to eat foods that are
enriched with vitamin D. Administer ordered oral
supplement.
Increased level: Note and report symptoms of
excesses or increased levels taken in medications
or vitamin supplements, or both (intoxication,
renal calculi, gastrointestinal intolerance).
Discontinue the oral intake of vitamin D, and
instruct client to avoid foods high in vitamin D.

TRACE MINERALS
Seven trace minerals are known to be essential to
human function even though they are present in
minute quantities in the body. These essential
minerals are cobalt, copper, iodine, iron, manganese,
molybdenum, and zinc.
Cobalt is a constituent of vitamin B12 and is
essential to the formation of red blood cells.
Copper participates in cytochrome oxidation of
tissue cells for energy production, promotes
absorption of iron from the intestines and transfer
from tissues to plasma, and is essential to hemoglobin formation. It also promotes bone and brain
tissue formation and supports the maintenance of
myelin. Iodine is an essential component for the
synthesis of thyroid hormones. Iron, which is
discussed in Chapter 1, is an essential component of
hemoglobin.
Manganese functions as a coenzyme in urea
formation and in the metabolism of proteins, fats,
and carbohydrates. Molybdenum facilitates the
enzymatic action of xanthine oxidase and liver aldehyde oxidase in purine catabolism and functions in
the formation of carboxylic acid. Zinc is an essential
component of cellular enzymes such as alkaline
phosphatase, carbonic anhydrase, lactic dehydrogenase, and carboxypeptidase, which function in
protein and carbohydrate metabolism. It also aids in
the storage of insulin, functions in deoxyribonucleic
acid (DNA) replication, assists in carbon dioxide
exchange, promotes body growth and sexual maturation, and may affect lymphocyte formation and
cellular immunity.
Other trace minerals are found in the body, but

CHAPTER 5—Blood

Chemistry

213

Reference Values
Conventional Units

SI Units

Cobalt

1 g/dL

1.7 nmol/L

Copper

130–230 g/dL

20.41–36.11 mol/L

Iodine (protein-bound)

4–8 g/dL

Manganese

4–20 mg/dL

Zinc

50–150 g/dL

7.6–23.0 mol/L

Chromium

0.3–0.85 g/L

5.7–16.3 nmol/L

their functions remain unclear. These minerals
include chromium, fluorine, lithium, arsenic,
cadmium, nickel, silicon, tin, and vanadium.
Deficiencies of trace minerals are likely only in
individuals dependent on parenteral nutrition,
because the normal diet provides adequate intake.
Elevated blood levels are usually caused by environmental contamination, either in industrial settings
or through water pollution.
INDICATIONS FOR TRACE MINERALS TEST

Monitoring of response to parenteral nutrition,
which may lead to deficiencies of trace minerals
Suspected exposure to environmental toxins,
which may be indicated by elevated levels of trace
minerals
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of a peripheral blood sample
(see Appendix I).
THE PROCEDURE

A venipuncture is performed and the sample
collected in a metal-free tube. The sample is handled
gently to avoid hemolysis and transported immediately to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of a
peripheral blood sample.
Abnormal values: Note and report deficiency or
decreased levels associated with anemia, poor
wound healing, reduced sexual maturation,
growth retardation, and the administration of
total parenteral nutrition that can eliminate some
trace minerals. Instruct client to eat foods high in
trace minerals. Administer oral supplements as
ordered.

DRUGS AND TOXIC SUBSTANCES
Blood levels of drugs are used to monitor attainment
of therapeutic drug levels, compliance with therapeutic regimens, and potential excess dosing. They
are also used in situations when accidental or deliberate drug overdose is suspected. In therapeutic situations, serial samples may be drawn to determine
peak (highest) and trough (lowest) blood levels of
drugs. Samples for peak drug levels are generally
drawn within 30 to 60 minutes of drug administration. Trough levels are drawn immediately before the
next dose of the drug is to be given. It is necessary to
know as exactly as possible the time the drug was
administered or ingested for accurate interpretation
of test results.
Many potential toxins are present in the household and in industrial settings. Data regarding circulating levels of toxic substances may be used to
diagnose either acute or chronic poisoning with
metals or common commercial substances.
Reference Values
Therapeutic and toxic levels of various drugs are
shown in Table 5–30. Toxic doses and effects of
industrial and household toxins are listed in
Table 5–31. For child values, refer to agency
laboratory information.
INDICATIONS FOR BLOOD LEVELS OF DRUGS
AND TOXIC SUBSTANCES TEST

Determination of therapeutic levels of prescribed
drugs, especially those with narrow therapeutic
ranges or serious toxic effects, or both
Evaluation of the degree of compliance with the
therapeutic regimen
Known or suspected drug overdose
Known or suspected exposure to environmental
toxins

214

SECTION I—Laboratory

Tests
TABLE 5–30

Drug

Peak Time

•

Blood Levels of Drugs
Duration
of Action

Therapeutic
Level

Toxic Level

2 days

20–25 g/mL

35 g/mL

34–43 mol/L

60 mol/L

4–8 g/mL

12 g/mL

8.4–16.8 mol/L

25.1 mol/L
35 g/mL

Antibiotics
Amikacin

IM: 1/2 hr
IV: 15 min

SI units
Gentamicin

IM: /2 hr

2 days

IV: 15 min
SI units
Kanamycin

1/2 hr

2 days

20–25 g/mL
42–52 mol/L

73 mol/L

/2–11/2 hr

5 days

25–30 g/mL

30 g/mL

IV: 15 min

2 days

2–8 g/mL

12 g/mL

4–17 mol/L

25 mol/L

SI units
Streptomycin
SI units
Tobramycin
SI units
Anticonvulsants
Barbiturates and barbiturate-related
Amobarbital

IV: 30 sec

10–20 hr

7 g/mL

30 g/mL

30 mol/L

132 mol/L

IV: 30 sec

15 hr

4 g/mL

15 g/mL

18 mol/L

66 mol/L
55 g/mL

SI units
Pentobarbital
SI units
Phenobarbital

15 min

80 hr

10 g/mL
43 mol/L

230 mol/L

PO: 3 hr

7–14 hr

1 g/mL

10 g/mL

4 mol/L

45 mol/L

SI units
Primidone
SI units
Benzodiazepines
Clonazepam (Klonopin)

1–4 hr

60 hr

SI units
Diazepam (Valium)

1–4 hr

1–2 days

SI units

5–70 ng/ml

70 ng/mL

55–222 mol/L

222 mol/L

5–70 ng/mL

70 ng/mL

0.01–0.25 mol/L

0.25 mol/L

10–20 g/mL

20 g/mL

40–80 mol/L

80 mol/L

Hydantoins
Phenytoin (Dilantin)

3–12 hr

7–42 hr

SI units
Succinimides
Ethosuximide (Zarontin)
SI units

1 hr

8 days

40–80 g/mL

100 g/mL

283–566 mol/L

708 mol/L

CHAPTER 5—Blood

TABLE 5–30
Drug

•

Duration
Peak Time

Chemistry

215

Blood Levels of Drugs
Therapeutic
of Action

Level

Toxic Level

Miscellaneous
Carbamazepine (Tegretol)

4 hr

2 days

SI units
Valproic acid (Depakene)

1–4 hr

2–10 g/mL

12 g/mL

8–42 mol/L

50 mol/L

50–100 g/mL

100 g/mL

350–700 mol/L

700 mol/L

8–9 hr

10–18 g/mL

20 g/mL

25–30 hr

2–4.5 g/mL

9 g/mL

5.9–13 mol/L

26 mol/L

2.4–5 g/mL

6 g/mL

7–15 mol/L

18 mol/L

4–8 g/mL

12 g/mL

17–35 mol/L

50 mol/L

2–8 g/mL

30 g/mL

24 hr

SI units
Bronchodilators
Aminophylline/theophylline

PO: 2 hr
IV: 15 min

Cardiac Drugs
Disopyramide (Norpace)

PO: 2 hr

SI units
Quinidine

PO: 1 hr

20–30 hr

IV: immediate
SI units
Procainamide (Pronestyl)

PO: 1 hr

10–20 hr

IV: /2 hr
SI units
NAPA (N-acetyl
procainamide,
a procainamide
metabolite)

—

IV: immediate

5–10 hr

7–29 mol/L

108 mol/L

2–6 g/mL

9 g/mL

8–25 mol/L

38 mol/L

6–8 hr

5–10 g/kg

30 g/kg

5–10 g/kg

15 g/kg

SI units
Lidocaine
SI units
Bretylium
Verapamil

15–30 min
PO: 5 hr

8–10 hr

IV: 3–5 min

IV: 1/2–1 hr

Diltiazem

PO: 2–3 hr

3–4 hr

50–200 ng/mL

200 ng/mL

Nifedipine

1–3 hr

3–4 hr

5–10 mg

90 mg

Digitoxin

4 hr

30 days

10–25 ng/mL

30 ng/mL

13–33 nmol/L

39 nmol/L

0.5–2 ng/mL

2.5 ng/mL

0.6–2.5 nmol/L

3.0 nmol/L

10–18 g/mL

20 g/mL

40–71 mol/L

80 mol/L

2.3–5 g/mL

5 g/mL

7–15 mol/L

15 mol/L

SI units
Digoxin

2 hr

7 days

SI units
Phenytoin (Dilantin)

PO: 2 hr

96 hr

SI units
Quinidine

IV: 1 hr
—

SI units

—

(Continued on the following page)

216

SECTION I—Laboratory

Tests

Evaluation of chronic exposure to industrial
products known to be toxic
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of a peripheral blood sample
(see Appendix I).

TABLE 5–30
Drug

•

THE PROCEDURE

Blood Levels of Drugs (Continued)

Duration
Peak Time

Therapeutic
of Action

Level

Toxic Level

Salicylates
2–20 mg/dL

30 mg/dL

SI units

0.1–1.4 mmol/L

2.1 mmol/L

2–30 mg/dL

40 mg/dL

SI units

0.1–2.1 mmol/L

2.8 mmol/L

0.005 mg/dL

Aspirin

15 min

12–30 hr

Narcotics
Codeine

—

17 nmol/L

SI units
Hydromorphone (Dilaudid)

0.1 mg/dL
350 nmol/L

SI units
Methadone

—

0.2 mg/dL
6.46 mol/L

SI units
Meperidine (Demerol)

0.5 mg/dL
20 mol/L

SI units
Morphine

—

0.005 mg/dL

—

10 g/mL

55 g/mL

43 mol/L

230 mol/L
30 g/mL

Barbiturates
Phenobarbital
SI units
Amobarbital

—

7 g/mL
30 mol/L

130 mol/L

—

4 g/mL

15 g/mL

17 mol/L

66 mol/L

3 g/mL

10 g/mL

12 mol/L

42 mol/L

0.1 g/dL

100 mg/dL

SI units
Pentobarbital
SI units
Secobarbital

—

SI units
Alcohols
Ethanol

—

(legal level for
intoxication)
Methanol

—

20 mg/dL

CHAPTER 5—Blood

TABLE 5–30
Drug

•

Chemistry

217

Blood Levels of Drugs

Duration
Peak Time

Therapeutic
of Action

—

Level

Toxic Level

Psychiatric Drugs
Amitriptyline (Elavil)
SI units
Imipramine (Tofranil)

—

SI units
Lithium (Lithonate)

1–4 hr

—

SI units

100–250 ng/mL

300 ng/mL

361–902 nmol/L

1083 nmol/L

100–250 ng/mL

300 ng/mL

357–898 nmol/L

1071 nmol/L

0.8–1.4 mEq/L

1.5 mEq/L

0.8–1.4 mol/L

1.5 mol/L

0–25 g/mL

150 g/mL

0–170 mol/L

1000 mol/L
4 hr after
ingestion

Miscellaneous
Acetaminophen

—

SI units

Prochlorperazine

—

0.5 g/mL

1.0 g/mL

Bromides

—

75–150 mg/dL

150 mg/dL

7–15 mmol/L

15 mmol/L

SI units

administered or ingested should be noted on the
laboratory request form.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of a
peripheral blood sample.
It may be necessary to withhold subsequent doses
of drugs administered for therapeutic reasons
until test results are available, but this practice
should be confirmed with the person prescribing
the medication.
Abnormal values: Note and report both therapeutic and toxic values for the drug test
performed. Notify the physician at once if any
value is at a critical level. Prepare for immediate
interventions to prevent cardiac arrest or other
manifestations of toxicity, such as ECG monitor-

ing, oxygen, or intubation and ventilation.
Administer ordered antidote or other medications.
Long-term drug therapy: Support client and
instruct in long-term medication regimen, which
symptoms to note and report, and when to
discontinue the medication.
Medicolegal aspects: Collection, delivery, possession, and transportation of the specimen should
be witnessed by a legally responsible person, and
the possession of it must remain unbroken from
the time of collection to the completion of any
legal court action (chain of evidence). Seal specimen to prevent tampering and label “Medicolegal
Case.” In some cases a number is used instead of a
name for identification. Toxicology tests to determine abuse, suicide, intentional overdose, or
suspected murder or attempted murder require
these considerations.

218

SECTION I—Laboratory

TABLE 5–31

•

Tests

Toxic Doses and Effects of Industrial and Household Toxins

Substance

Toxic Dose

Toxic Effects

Aniline

50 mg/kg

Methemoglobinemia, hepatotoxicity,
nephrotoxicity

Arsenic/antimony

5 mg/kg

Gastric hemorrhage, shock

Barium salts

—

Bloody diarrhea, cardiac depression,
muscle spasms, respiratory failure, renal
failure

Benzene products

50 mg/kg

CNS depression, respiratory failure, cardiac
arrest, bone marrow depression, liver
damage

Bismuth

0.1–3.5 g/L

Weakness, fever, anorexia, black gum line,
renal damage

Cadmium

41 ng/mL

Severe gastroenteritis, liver damage, acute
renal failure; if inhaled as dust or fumes,
pulmonary edema

Carbon tetrachloride

5–10 mL (total)

CNS depression, liver and kidney failure

Chlorate or bromate salts

50 mg/kg

Methemoglobinemia, intravascular hemolysis, acute renal failure

Cobalt

0.11–0.45 g/L

Nerve damage, thyroid dysfunction

Copper salts

50 mg/kg

Generalized capillary damage, kidney and
liver damage

Cyanide

5 mg total (0.5 mg/100
mL of blood)

Confusion, dyspnea, convulsions, death
from respiratory failure

DDT

50 mg/kg

Fatigue, confusion, ataxia, convulsions,
death from respiratory failure

2.4-D

—

Lethargy, diarrhea, cardiac arrest, hyperpyrexia, convulsion, coma

Ergot

5 mg/kg

Gastrointestinal inflammation, renal
damage, gangrene of fingers and toes
caused by persistent peripheral vascoconstriction

Ethylene glycol

5 mg/kg

CNS depression, death from renal failure or
respiratory paralysis

Iron salts

500 mg/kg

Bloody diarrhea, shock, liver damage

Fluoride

50 mg/kg (0.2–0.3 mg/dL of
blood)

Hemorrhagic gastroenteritis, tremors,
hypocalcemia, shock

Formaldehyde

500 mg/kg

Hemorrhagic gastroenteritis, renal failure,
circulatory collapse

Hydrogen sulfide

0.1–0.2% in air

Death from respiratory paralysis

Sodium hypochlorite

Several ounces of household bleach

Edema of pharynx, glottis, larynx; perforation of esophagus or stomach, pulmonary
edema from fumes

Iodine

5 mg/kg

Bloody diarrhea, renal damage, death from
asphyxia or circulatory collapse

CHAPTER 5—Blood

TABLE 5–31

•

Chemistry

219

Toxic Doses and Effects of Industrial and Household Toxins

Substance

Toxic Dose

Toxic Effects

Ipecac, syrup or fluid
extract

1–2 oz fluid extract (14
times more concentrated
than syrup)

Shock caused by intractable vomiting and
diarrhea, death from cardiac depression

Isopropyl alcohol

500 mg/kg

Severe CNS depression, death from respiratory failure or circulatory collapse

Kerosene

500 mg/kg if swallowed;
few mL lethal if aspirated

Severe chemical pneumonitis, coma

Lead

30 g/kg (120 g/L blood
level)

Gastrointestinal inflammation, liver and
kidney damage, encephalopathy in children, paralysis of extremities, death from
encephalopathy or peripheral vascular
collapse

Lye, sodium and potassium hydroxide

10 g total dose may be
fatal

Laryngeal or glottic edema, perforation of
esophagus or stomach, severe diarrhea,
shock, death

Mercury salts

5 mg/kg

Acute: Death from acute renal failure or
peripheral vascular collapse
Chronic: Progressive peripheral neuritis,
death from renal failure

Naphthalene (mothballs)

5 g/kg

CNS excitement or depression, acute
hemolytic anemia, convulsions

Nicotine

5 mg/kg

CNS stimulation followed by depression;
vomiting, diarrhea, dyspnea, death from
respiratory paralysis

Oxalic acid

50 mg/kg

Shock caused by severe gastroenteritis,
hypocalcemia, convulsions, renal
damage, coma, death

Parathion/organophosphorus insecticides

5 mg/kg

Vomiting, diarrhea, generalized muscle
weakness, convulsions, coma, death, all
caused by inhibition of acetylcholinesterase and accumulation of
cholinesterase at myoneural junctions

Phosphorus

5 mg/kg

Penetrating burns; liver, kidney, and cardiac
damage

Quaternary ammonium
germicides

5 mg/kg

CNS depression, dyspnea, death from
asphyxia

Rotenone

50 mg/kg

Severe hypoglycemia, tremors, convulsions, respiratory stimulation followed by
depression, death from respiratory arrest

Selenium

58–234 g/L

Metallic taste, nausea, vomiting, headache,
pulmonary disorders

Silver salts

3.5–35 g total dose

Bloody diarrhea, severe corrosion of the
gastrointestinal tract, coma, convulsions,
death
(Continued on the following page)

220

SECTION I—Laboratory

TABLE 5–31

Substance

•

Tests

Toxic Doses and Effects of Industrial and Household
Toxins (Continued)
Toxic Dose

Toxic Effects

Strychnine

5 mg/kg

Stimulation of spinal cord, tetanic convulsions, death in 1–3 hr (with the face fixed
in a grin and the body arched in hyperextension) from anoxia

Thallium salts

5 mg/kg (50 g/L blood
level)

Hemorrhagic gastroenteritis, encephalopathy (delirium, convulsions, coma), death

Turpentine

500 mg/kg

Aspiration pneumonitis, vomiting, diarrhea,
CNS excitement (delirium), stupor,
convulsions, coma, death from respiratory failure

Zinc

70–50 g/L

Hypertension, tachycardia nausea, vomiting, diarrhea, cough, metallic taste

REFERENCES
1. Sacher, RA, and McPherson, RA: Widmann’s Clinical Inter-pretation of Laboratory Tests, ed 11. FA Davis, Philadelphia, 2000, p 321.
2. Ibid, pp 322–323.
3. Ibid, p 323.
4. Ibid, p 324.
5. Ibid, p 323.
6. Ibid, p 325.
7. Ibid, p 605.
8. Ibid, p 611.
9. Ibid, p 326.
10. Ibid, pp 610–611.
11. Ibid, p 606.
12. Ibid, p 326.
13. Springhouse Corporation: Nurse’s Reference Library, Diagnostics,
ed 2. Springhouse, Springhouse, PA, 1986, p 242.
14. Fischbach, FT: A Manual of Laboratory Diagnostic Tests, ed 4. JB
Lippincott, Philadelphia, 1992, p 303.
15. Sacher and McPherson, op cit, p 606.
16. Ibid, p 607.
17. Ibid, p 433.
18. Hillman, RS, and Finch, CA: Red Cell Manual, ed 7. FA Davis,
Philadelphia, 1996, p 23.
19. Sacher and McPherson, op cit, p 328.
20. Ibid, p 329.
21. Ibid, pp 433–434.
22. Ibid, p 338.
23. Guyton, AC: Textbook of Medical Physiology, ed 6. WB Saunders,
Philadelphia, 1981, pp 849–850.
24. Ibid, pp 856–857.
25. Sacher and McPherson, op cit, pp 332, 425.
26. Ibid, pp 397–398.
27. Ibid, pp 402–403.
28. Ibid, pp 400–401, 427–428.
29. Kontos, MC, et al: Use of the combination of myoglobin and CKMB mass for rapid diagnosis of acute myocardial infarction. Am J
Emerg Med, 15(1):14–19, 1997.
30. Sacher and McPherson, op cit, pp 406–409.
31. Collinson, PO: Troponin T or troponin I or CK-MB (or none?).
Eur Heart J, 19(Suppl N):N16–24, 1998.

32. Sommers, M, and Johnson, S: Davis’s Manual of Nursing
Therapeutics for Diseases and Disorders. FA Davis, Philadelphia,
1997.
33. Kost, GJ, Kirk, JD, and Omand, K: A strategy for the use of cardiac
injury markers (troponin I and T, creatine kinase-MB mass and
isoforms, and myoglobin) in the diagnosis of acute myocardial
infarction. Arch Pathol Lab Med, 122(3):245–251, 1998.
34. Lindahl, B, Venge, P, and Wallentin, L: The FRISC experience with
troponin T. Use as decision tool and comparison with other prognostic markers. Eur Heart J, 19(Suppl N):N51–58, 1998.
35. Sacher and MacPherson, op cit, pp 411–412.
36. Berkow, R (ed): The Merck Manual, ed 16. Merck Research
Laboratories, Rahway, NJ, 1992, p 1839.
37. Sacher and McPherson, op cit, pp 405–406.
38. Ibid, pp 555–556.
39. Ibid.
40. Ibid, p 557.
41. Ibid, pp 557, 634.
42. Ibid, pp 583, 587, 590–591.
43. Ibid, pp 621–623.
44. Ibid, pp 617–627.
45. Ibid, pp 559–562.
46. Ibid, pp 582–583.
47. Guyton, op cit, pp 931–937, 984.
48. Sacher and McPherson, op cit, pp 585–586, 588.
49. Ibid, pp 586–587.
50. Ibid, pp 582–583, 590–592.
51. Ibid, pp 594, 598–601.
52. Ibid, pp 562, 577.
53. Ibid, pp 565–568.
54. Ibid, pp 572–573.
55. Ibid, pp 577–579.
56. Ibid, pp 631–632.
57. Ibid, pp 633–634.
58. Ibid, pp 603–604.
59. Ibid, pp 604, 611.
60. Ibid, pp 367–368.
61. Ibid, pp 379, 383.
62. Ibid, pp 357, 596.
63. Ibid, pp 380–381.

CHAPTER

Studies of Urine
TESTS COVERED
Routine Urinalysis, 222
Clearance Tests and Creatinine Clearance,
239
Tubular Function Tests and
Phenolsulfonphthalein Test, 240
Concentration Tests and Dilution Tests,
241
Electrolytes, 244

Pigments, 247
Enzymes, 250
Hormones and Their Metabolites, 252
Proteins and Their Metabolites, 261
Vitamins and Minerals, 263
Microbiologic Examination of Urine, 264
Cytologic Examination of Urine, 265
Drug Screening Tests of Urine, 265

OVERVIEW OF URINE FORMATION AND ANALYSIS Because urine results from
filtration of blood, many of the substances carried in the blood are also found in the urine. The
nature and amount of the substances present in urine reflect ongoing physiological processes
in health and disease states. The comparative ease of obtaining urine samples ensures the
continued use of urine studies as an aid to diagnosis.1
Urine is an ultrafiltrate of plasma from which substances essential to the body are reabsorbed
and through which substances that are not needed are excreted. Normally, 25 percent of the
cardiac output perfuses the kidneys each minute. This perfusion results in the production of
180 L of glomerular filtrate per day, 90 percent of which is reabsorbed. In addition to water,
substances reabsorbed include glucose, amino acids, and electrolytes. Substances excreted from
the body include urea, uric acid, creatinine, and ammonia. The major electrolytes lost are chloride, sodium, and potassium. Other substances found in urine include pigments, enzymes,
hormones and their metabolites, vitamins, minerals, and drugs. Red blood cells, white blood
cells, epithelial cells, crystals, mucus, and bacteria may also be found in urine.2,3
In general, the concentration of most substances normally found in the urine reflects the
plasma levels of the substances. If the plasma concentration of a substance is high, more of it is
lost in the urine in the presence of normal renal function. Conversely, if the plasma concentration is abnormally low, the substance is reabsorbed. The concentration of substances found in
the urine is also affected by factors such as dietary intake, body metabolism, endocrine function, physical activity, body position, and time of day.4 For these reasons, results of urine tests
must be evaluated in relation to the client’s history and current health status. For some studies,
urine specimens are collected at certain times of day or over 24-hour periods. Dietary intake
may also be modified for certain studies.
Commercially prepared reagent dipsticks are available to perform simple and quick testing
in hospitals, clinics, physicians’ offices, and homes. They are used for routine screening of single
or multiple urinary evaluations of protein, glucose, ketones, hemoglobin, urobilinogen, and
nitrites as well as pH. The strips contain reagents that react with specific substances by changing color. Color change is observed and compared to a color chart for the presence of abnor221

222

SECTION I—Laboratory

Tests

mal levels of substances. Special care in their use is required to prevent inaccurate results, and
confirmation of quantitative tests is appropriate if results from the dipstick testing reveal
abnormalities.
Urine samples for more exhaustive laboratory testing may be obtained through a variety of
methods. These are described in Appendix II. Urine studies include routine urinalysis, clearance tests, tubular function tests, concentration tests, and analyses for specific substances such
as electrolytes, pigments, enzymes, hormones and their metabolites, proteins, and vitamins and
minerals. Microbiologic and cytologic examination of urine may also be performed.

ROUTINE URINALYSIS
A routine urinalysis (UA) has two major components: (1) macroscopic analysis and (2) microscopic
analysis. Macroscopic analysis includes examining
the urine for overall physical and chemical characteristics. The microscopic component of a UA
involves examining the sample for formed elements,
also termed urinary sediment.
Urine samples for routine analysis are best
collected first thing in the morning. Urine that has
accumulated in the bladder overnight is more
concentrated, thus allowing detection of substances
that may not be present in more dilute random
samples.5 The sample should be examined within 1
hour of collection. If this is not possible, the sample
may be refrigerated until it can be examined. Failure
to observe these precautions may lead to invalid
results. If, for example, the sample is allowed to stand
for long periods without refrigeration, the glucose
level may drop and the ketones may dissipate. The
color of the urine may also deepen. Similarly,
urinary sediment begins deteriorating within 2
hours of sample collection. If bacteria are present,
they may multiply if the sample is neither examined
promptly nor refrigerated. Also, the pH of the
sample may be altered, rendering it more alkaline. If
the sample is exposed to light for long periods of
time, bilirubin and urobilinogen may be oxidized.6

MACROSCOPIC ANALYSIS
COLOR

The color of urine is mainly a result of the presence
of the pigment urochrome, which is produced
through endogenous metabolic processes. Because
urochrome is normally produced at a fairly constant
rate, the intensity of the yellow color may indirectly
indicate urine concentration and the client’s state of
hydration.7,8 Pale urine with a low specific gravity
may occur, for example, in a normal person after
high fluid intake. Note, however, that an individual
with uncontrolled or untreated diabetes may also

produce pale urine. The pale urine in this case is
caused by osmotic diuresis resulting from the excessive glucose load. The client actually may be dehydrated. Further, the specific gravity of the urine from
such an individual could be high because of the
presence of excessive glucose.9 Similarly, deeper
colored urine may not always indicate concentrated
urine. The presence of bilirubin may produce darker
urine in normally hydrated individuals.
Urine color may be described as pale yellow,
straw, light yellow, yellow, dark yellow, and amber.
For the most accurate appraisal of urine color, the
sample should be examined in good light against a
white background. If the sample is allowed to stand
at room temperature for any length of time, the
urochrome will increase and the color of the sample
may deepen.10
Numerous factors that affect the color of urine are
listed in Table 6–1.
APPEARANCE (CLARITY)

The term appearance generally refers to the clarity of
the urine sample. Urine is normally clear or slightly
cloudy. In alkaline urine, cloudiness may be caused
by precipitation of phosphates and carbonates. In
acidic urine, cloudiness may be caused by precipitation of urates, uric acid, or calcium oxalate. The
accumulation of uroerythrin, a pink pigment
normally present in urine, may produce a pinkish or
reddish haze in acidic urine.
The most common substances that may cause
cloudy urine are white blood cells, red blood cells,
bacteria, and epithelial cells. Presence of these
substances may indicate inflammation or infection
of the urinary and genital tracts and must be
confirmed through microscopic examination. Other
substances that may produce cloudy urine are
mucus, yeasts, sperm, prostatic fluid, menstrual and
vaginal discharges, fecal material, and external
substances such as talcum powder and antiseptics.11
Proper client instruction and specimen collection
may aid in reducing the presence of such substances
in the urine.

CHAPTER 6—Studies

•

TABLE 6–1
Urine Color
Very pale yellow

Factors Affecting the Color of Urine

Cause
Excessive fluid intake

Urine Color
Green

Diabetes insipidus

Vitamins

Nephrotic syndrome

Psychoactive drugs

Alcohol

Proprietary diuretics
Blue

Nitrofurans

Anxiety

Proprietary diuretics

Underhydration

Methylene blue
Brown

Acid hematin

Urobilin

Myoglobin

Carrots

Bile pigments

Phenacetin

Levodopa

Cascara

Nitrofurans

Nitrofurantoin

Some sulfa drugs

Chlorpromazine
Quinacrine
Riboflavin
Sulfasalazine
Bilirubin
Phenazopyridine
(Pyridium)

Red

Biliverdin
Pseudomonas

Bilirubin

Orange

Cause

Diabetes mellitus

Diuretics

Dark yellow, amber

of Urine

Rhubarb
Black, brownish
black

Melanin
Homogentisic acid
Indicans
Urobilin

Azo drugs

Red blood cells
oxidized to
methemoglobin

Phenothiazine

Levodopa

Oral anticoagulants

Cascara

Red blood cells

Iron complexes

Hemoglobin

Phenols

Myoglobin
Porphyrins
Porphobilinogen
Many drugs and dyes
Rifampin
Phenolsulfonphthalein
Fuscin
Beets
Rhubarb
Senna

223

224

SECTION I—Laboratory

Tests

Lymph and fat globules in urine can also yield
cloudy specimens. The presence of lymph in the
urine is most often associated with obstruction of
abdominal lymph flow and rupture of lymphatic
vessels into portions of the urinary tract. Fat globules in the urine are most commonly associated with
nephrotic syndrome but may also be seen in clients
with fractures of the long bones or pelvis.12
ODOR

Normally, a fresh urine specimen has a faintly
aromatic odor. As the specimen stands, the odor of
ammonia predominates because of the breakdown
of urea. Ingestion of certain foods and drugs impart
characteristic odors to urine; this is especially true of
asparagus.
Some unusual odors are indicative of certain
disease states. Urine with a fruity odor, for example,
may indicate ketonuria resulting from uncontrolled
diabetes mellitus or starvation. Other abnormal
odors are associated with amino acid disorders.
Urine with a “mousy” smell is associated with
phenylketonuria (PKU), whereas urine that smells
like maple syrup is associated with maple syrup
urine disease. Urine with a “fishy” or fetid odor is
generally associated with bacterial infection. This
odor is especially noticeable when urine is allowed to
stand for some time. Occasionally, urine may lack an
odor. This characteristic is seen in acute renal failure
because of acute tubular necrosis and failure of
normal mechanisms of ammonium secretion.13,14
SPECIFIC GRAVITY

The specific gravity of urine is an indication of the
kidney’s ability to reabsorb water and chemicals
from the glomerular filtrate. It also aids in evaluating hydration status and in detecting problems
related to secretion of antidiuretic hormone. By definition, specific gravity is the density of a liquid
compared with that of a similar volume of distilled
water when both solutions are at the same or similar
temperatures. The normal specific gravity of
distilled water is 1.000. The specific gravity of urine
is greater than 1.000 and reflects the density of the
substances dissolved in the urine. Both the number
of particles present and their size influence the
specific gravity of urine. Large urea molecules, for
example, influence the specific gravity more than do
small sodium and chloride molecules. Similarly, if
large amounts of glucose or protein are present in
the sample, the specific gravity will be higher.15
The specific gravity of the glomerular filtrate is
normally 1.010 as it enters Bowman’s capsule. A
consistent urinary specific gravity of 1.010 usually
indicates damage to the renal tubules such that

concentrating ability is lost. Urine with a low specific
gravity may be seen in clients with overhydration
and diabetes insipidus. Urine with a high specific
gravity is associated with dehydration, uncontrolled
diabetes mellitus, and nephrosis. High specific gravities may also be seen in clients who are receiving
intravenous (IV) solutions of dextran or other highmolecular-weight fluids and in those who have
received radiologic contrast media.
The specific gravity of urine provides preliminary
information. For a more thorough evaluation of
renal concentrating ability, urine osmolality may be
determined, and concentration tests may be
performed.16
PH

The pH of urine reflects the kidney’s ability to regulate the acid–base balance of the body. In general,
when too much acid is present in the body (i.e.,
respiratory or metabolic acidosis), acidic urine (low
pH) is excreted. Conversely, alkaline urine (high pH)
is excreted in states of respiratory or metabolic alkalosis. Various foods and drugs also affect urinary pH.
The kidney controls the acid–base balance of the
body through regulation of hydrogen ion excretion.
Various acids are excreted via the glomerulus along
with sodium ions. In the renal tubules, bicarbonate
ions are reabsorbed and hydrogen ions are secreted
in exchange for sodium ions. Additional hydrogen
ions are excreted as ammonium.
Disorders involving the renal tubules affect regulation of pH. In renal tubular acidosis, for example,
the ability of the distal tubules to secrete hydrogen
ions and form ammonia is impaired. Metabolic
acidosis results. Similarly, in proximal tubular acidosis, bicarbonate is wasted.
As noted previously, the acidity or alkalinity of
the urine generally reflects that of the body. A paradoxic situation can occur, however, in clients with
hypokalemic alkalosis, which can occur with
prolonged vomiting or excessive use of diuretics. In
this situation, an acidic urine may be produced
when hydrogen ions are secreted instead of potassium ions (which are deficient) to maintain electrochemical neutrality in the renal tubules.17
The pH or urine samples must be evaluated in
relation to the client’s dietary and drug intake. A diet
high in meat and certain fruits such as cranberries
produces acidic urine. A diet high in vegetables and
citrus fruits produces an alkaline urine. Drugs such
as ammonium chloride and methenamine mandelate produce an acid urine, whereas sodium bicarbonate, potassium citrate, and acetazolamide result
in alkaline urine.
The changes in urinary pH that occur in relation

CHAPTER 6—Studies

to ingestion of certain foods and drugs are applied to
the treatment of certain urinary tract disorders.
Maintenance of an acidic urine may be used in the
treatment of urinary tract infections (UTIs) because
urea-splitting organisms do not multiply as rapidly
in an acidic environment. These same organisms
cause the pH of a urine specimen to rise if it is
allowed to stand for a period of time.18 Acidic urine
also helps to prevent the formation of ammonium
magnesium kidney stones, which are more likely to
form in alkaline urine. Other types of kidney stones
are more likely to be prevented if the urine is alkaline. The induction of alkaline urine may also be
used in the treatment of UTIs with drugs such as
kanamycin, in sulfonamide therapy, and in the treatment of salicylate poisoning.19
Urine is generally less acidic after a meal (the
“alkaline tide”) because of secretion of acids into the
stomach. Urine tends to be more acidic in the morning as a result of the mild respiratory acidosis that
normally occurs during sleep.20 Thus, the time of
day at which the sample is collected may influence
evaluation of urinary pH.
PROTEIN

Urine normally contains only a scant amount of
protein, which derives from both the blood and the
urinary tract itself. The proteins normally filtered
through the glomerulus include small amounts of
low-molecular-weight serum proteins such as albumin. Most of these filtered proteins are reabsorbed
by the proximal renal tubules. The distal renal
tubules secrete a protein (Tamm-Horsfall mucoprotein) into the urine. Other normal proteins in urine
include microglobulin, immunoglobulin light
chains, enzymes and proteins from tubular epithelial
cells, leukocytes, and other cells shed by the urinary
tract. More than 200 urinary proteins have been
identified.21
Normal protein excretion must be differentiated
from that which is caused by disease states. Persons
who do not have renal disease may have proteinuria
after strenuous exercise or during dehydration.
Functional (nonrenal) proteinuria may also be seen
in congestive heart failure (CHF), cold exposure,
and fever.22
Postural (orthostatic) proteinuria may also occur
in a small percentage of normal individuals. In this
situation, the client spills protein while in an upright
posture but not when recumbent. Postural proteinuria is evaluated by having the client collect a urine
sample on first arising and then approximately 2
hours later after having been up and about. The
second sample should be positive for protein; the
first should be negative. Orthostatic proteinuria is

of Urine

225

generally a benign condition, although the client
should be reevaluated periodically for persistent,
nonpostural proteinuria.
Persistent proteinuria is generally indicative of
renal disease or of systemic disorders leading to
increased serum levels of low-molecular-weight
proteins. Renal disease resulting in proteinuria may
be a result of damage to the glomerulus or to the
renal tubules. When the glomerular membrane is
damaged, greater amounts of albumin pass into the
glomerular filtrate. If damage is more extensive,
large globulin molecules are also excreted. Nephrotic
syndrome is an example of renal disease primarily
associated with glomerular damage. In this disorder
there is heavy proteinuria accompanied by decreased
serum albumin. In contrast, renal disease resulting
from tubular damage is characterized by loss of
proteins that are normally reabsorbed by the tubules
(i.e., low-molecular-weight proteins). An example of
renal disease primarily associated with tubular
damage is pyelonephritis. The proteinuria that
occurs in disorders involving the renal tubules is
generally not as profound as that associated with
glomerular damage.23,24
Systemic disorders that result in excessive production or release of hemoglobin, myoglobin, or
immunoglobulins may lead to proteinuria and may,
in addition, lead to actual renal disease.
Myoglobinemia, for example, which may occur with
extensive destruction of muscle fibers, leads to
excretion of myoglobin in the urine and may lead to
acute renal tubular necrosis.25 Multiple myeloma, a
neoplastic disorder of plasma cells, is another example of a systemic disorder that may cause proteinuria. In this disorder, the blood contains excessive
levels of monoclonal immunoglobulin light chains
(Bence Jones protein).26 This protein overflows
through the glomerulus in quantities greater than
the renal tubules can absorb. Thus, large amounts of
Bence Jones protein appear in the urine. As with
myoglobinuria, the excessive amounts of protein can
ultimately damage the kidney itself.
Because proteinuria may indicate serious renal or
systemic disease, its detection on UA must always be
further evaluated for possible cause. Proteinuria
occurring in the latter months of pregnancy also
must be carefully evaluated because it may indicate
serious complications of pregnancy.
GLUCOSE

Normally, glucose is virtually absent from the urine.
Although nearly all glucose passes into the glomerular filtrate, most of it is reabsorbed by the proximal
renal tubules through active transport mechanisms.
In active transport, carrier molecules attach to mole-

226

SECTION I—Laboratory

Tests

cules of other substances (e.g., glucose) and transport them across cell membranes. Usually there are
enough carrier molecules to transport all of the
glucose from the renal tubules back to the blood. If
plasma glucose levels are very high, however, such
that carrier mechanisms are overwhelmed, glucose
will appear in the urine. The point at which a
substance appears in the urine is called its renal
threshold.27 The renal threshold for glucose ranges
from 160 to 200 mg/dL, depending on the individual. That is, the blood sugar must rise to its renal
threshold level before glucose appears in the urine.
The most common cause of glycosuria is uncontrolled diabetes mellitus. Because even a normal
person may have elevated blood glucose levels
immediately after a meal, urine samples for glucose
are best collected immediately before meals, when
the blood sugar should be at its lowest point.
Similarly, urine that has been accumulating in the
bladder overnight may contain excessive amounts of
glucose resulting from increased concentration of
urine and perhaps also from something eaten the
previous evening. Because a negative test result for
urinary sugar may not necessarily indicate a normal
blood sugar level and because there is a great deal of
variation in individual renal thresholds for glucose,
recent trends for diabetes control have moved away
from urinary glucose monitoring to blood glucose
monitoring. Evaluation of glucose in routine urine
specimens, however, remains a useful screening
technique.
In addition to diabetes mellitus, many other
disorders can result in glycosuria. In general, these
disorders fall into two general categories: (1) those
in which the blood sugar is elevated and (2) those in
which the blood sugar is not elevated but in which
renal tubular absorption of glucose is impaired.
Disorders that may lead to elevated blood glucose
levels and, thus, to glycosuria are listed in Table 6–2.
In addition, several drugs are known to elevate the
blood sugar enough to produce glycosuria. These
also are listed in Table 6–2.
When renal tubular reabsorption of glucose is
impaired, glucose may appear in the urine without
actual hyperglycemia. In disorders involving the
renal tubules, glycosuria is one of many abnormal
findings. Reabsorption of amino acids, bicarbonate,
phosphate, sodium, and water may also be impaired.
Disorders associated with altered renal tubular function and glycosuria are listed in Table 6–2.
Pregnancy represents a special case in which glycosuria may be present without hyperglycemia.
During pregnancy, the glomerular filtration rate
(GFR) is increased so that it may not be possible for
the renal tubules to reabsorb all of the glucose
presented. Glucose may appear in the urine even

though blood glucose levels are within normal
limits. This situation must be distinguished from
actual diabetes with elevated blood sugar levels, a
serious complication of pregnancy.28
Certain drugs are known to produce false-positive
results when testing for glucose in urine, especially
when copper sulfate reduction testing methods (e.g.,
Clinitest tablets, Benedict’s solution) are used. These
drugs are listed in Table 6–3. Allowing urine specimens to remain at room temperature for long periods may produce false-positive results.
The presence of nonglucose sugars in the urine
may also produce false-positive results in tests for
glycosuria. These sugars include lactose, fructose,
galactose, pentose, and sucrose. Lactose may appear
in the urine during normal pregnancy and lactation,
in lactase deficiency states, and in certain disorders
affecting the intestines (e.g., celiac disease, tropical
sprue, and kwashiorkor). Fructose may appear in the
urine after parenteral feedings with fructose and in
clients with inherited enzyme deficiencies, which are
generally benign in nature. Galactose in the urine
also is associated with certain inherited enzyme deficiencies. Pentose may appear in the urine after ingestion of excessive amounts of fruits. Similarly, sucrose
may be found if large amounts of sucrose are
ingested, but it may also be found in clients with
intestinal disorders associated with sucrase deficiency (e.g., sprue).29
Glycosuria may, therefore, indicate a number of
pathological states or may result from drug and food
ingestion. A thorough history and further evaluation
through additional laboratory tests are indicated
whenever glycosuria occurs.
KETONES

The term ketones refers to three intermediate products of fat metabolism: acetone, acetoacetic acid, and
-hydroxybutyric acid. Measurable amounts of
ketones are not normally present in urine. With
excessive fat metabolism, however, ketones may be
found. Excessive fat metabolism can occur in several
situations: (1) impaired ability to metabolize carbohydrates, (2) inadequate carbohydrate intake, (3)
excessive carbohydrate loss, and (4) increased metabolic demand.30 The disorder most commonly associated with impaired ability to metabolize
carbohydrates is diabetes mellitus. Because carbohydrates cannot be used to meet the body’s energy
needs, fats are burned, leading to the presence of
ketones in the urine. A similar situation occurs when
carbohydrate intake is inadequate to the body’s
needs. This is seen in weight-reduction diets and
starvation. Excessive loss of carbohydrates (e.g.,
caused by vomiting and diarrhea) and increased
metabolic demand (e.g., acute febrile conditions and

CHAPTER 6—Studies

TABLE 6–2

•

of Urine

Disorders and Drugs That May Result in Glycosuria

Glycosuria with High Blood Sugar
Diabetes mellitus

Glucosuria without High Blood Sugar
Renal tubular dysfunction

Gestational diabetes

Fanconi’s syndrome

Acromegaly

Galactosemia

Cushing’s syndrome

Cystinosis

Hyperthyroidism

Lead poisoning

Pheochromocytoma

Multiple myeloma

Advanced cystic fibrosis

Pregnancy (must be distinguished from gestational diabetes)

Hemochromatosis
Severe chronic pancreatitis
Carcinoma of the pancreas
Hypothalamic dysfunction
Brain tumor or hemorrhage
Massive metabolic derangement
Severe burns
Uremia
Advanced liver disease
Sepsis
Cardiogenic shock
Glycogen storage disease
Obesity
Medication-induced hyperglycemia
Adrenal corticosteroids
Adrenocorticotropic hormone
Thiazides
Oral contraceptives
Excessive IV glucose
Dextrothyroxine

TABLE 6–3

227

•

Drugs That May Produce False-Positive Glycosuria Results

Ascorbic acid

Oxytetracycline (Terramycin)

Cephalosporins

Para-aminobenzoic acid (PABA)

Chloral hydrate

Paraldehyde

Levodopa

Penicillins

Metaxalone (Skelaxin)

Salicylates

Morphine

Streptomycin

Nalidixic acid (NegGram)

Radiographic contrast media

228

SECTION I—Laboratory

Tests

toxic states, especially in infants and children) can
also produce ketonuria. Other disorders in which
ketones may be found in the urine include lactic
acidosis and salicylate toxicity. Ketonuria also has
been found after anesthesia and is believed to be a
result of both decreased food intake before surgery
and increased metabolic demand in relation to physiological stressors.
As with glucose, ketones in the urine are associated with elevated blood ketone levels. Because
ketone bodies are acids, ketonuria may indicate
systemic acidosis. Ketones in urine are measured
most frequently in clients with diabetes mellitus and
in those on weight-reduction diets. The finding of
ketones on UA requires further follow-up through
history and laboratory tests to determine the source.
Individuals receiving levodopa, paraldehyde,
phenazopyridine (Pyridium), and phthalein
compounds may produce false-positive results when
tested for ketonuria.
BLOOD

Blood can be present in the urine as either red blood
cells or hemoglobin. If enough blood is present, the
color of the sample can range from pink-tinged to
red to brownish-black. Very small amounts of blood,
although clinically significant, may not be detected
unless the sample is tested with reagent strips
(“dipsticks”) or by microscopic examination. The
dipstick approach for macroscopic UA provides a
useful screening approach. Positive results require
further evaluation to determine the nature and
source of the blood.31,32
The presence of red blood cells in urine (hematuria) is relatively common, whereas the presence of
hemoglobin in urine (hemoglobinuria) is seen
much less frequently. Hematuria is usually associated with disease of or damage to the genitourinary
tract. When hematuria is accompanied by significant
proteinuria, kidney disease is generally indicated
(e.g., acute glomerulonephritis). In contrast, hematuria with only small amounts of protein is associated with inflammation and bleeding of the lower
urinary tract (e.g., cystitis).33 Other disorders
commonly associated with hematuria include
pyelonephritis, tumors of the genitourinary tract,
kidney stones, lupus nephritis, and trauma to the
genitourinary tract. Nonrenal causes of hematuria
include bleeding disorders and anticoagulant therapy. Hematuria may also occur in healthy individuals after excessive strenuous exercise because of
damage to the mucosa of the urinary bladder.34
Free hemoglobin is not normally found in the
urine. Instead, any hemoglobin that could be

presented to the glomerulus combines with haptoglobin. The resultant hemoglobin–haptoglobin
complex is too large to pass through the glomerular
membrane. If the amount of free hemoglobin
exceeds the amount of haptoglobin, however, the
hemoglobin will pass through the glomerulus and
ultimately be excreted into the urine.35 Any disorder
associated with hemolysis of red blood cells and
resultant release of hemoglobin can lead to the
appearance of hemoglobin in the urine. Common
causes of hemoglobinuria include hemolytic
anemias, transfusion reactions, trauma to red blood
cells by prosthetic cardiac valves, extensive burns,
trauma to muscles and blood vessels, and severe
infections. Hemoglobinuria may also occur in
healthy individuals and is thought to be caused by
trauma to small blood vessels.36
Note that hemoglobin is broken down in the renal
tubular cells into ferritin and hemosiderin.
Hemosiderin may, therefore, be found in urine a few
days after an episode of acute red cell hemolysis.
Hemosiderin also is found in the urine of individuals with hemochromatosis, a disorder of iron metabolism.37
BILIRUBIN AND UROBILINOGEN

If the urine sample for UA appears dark or if the
client is experiencing jaundice, the specimen can be
tested for the presence of bilirubin and excessive
urobilinogen. Both of these substances are bile
pigments that result from the breakdown of hemoglobin (Fig. 6–1).
The average life span of red blood cells is 120 days.
Old and damaged cells are broken down primarily in
the spleen and to some extent in the liver. The breakdown products are iron, protein, and protoporphyrin. The body reuses the iron and protein; the
protoporphyrin is converted into bilirubin and is
released into the circulation, where it combines with
albumin. This form of bilirubin is called unconjugated or prehepatic bilirubin. It does not pass into
the urine because the complex is insoluble in water
and is too large to pass through the glomerular
membrane. When circulating unconjugated bilirubin reaches the liver, it is conjugated with glucuronic
acid. The conjugated (posthepatic) bilirubin is
normally absorbed into the bile ducts, stored in the
gallbladder, and ultimately excreted via the intestine.38 In the intestine, bilirubin is converted into
urobilinogen by bacteria. Approximately half of the
urobilinogen is excreted in the stools, where it is
converted into urobilin; the remaining half is reabsorbed from the intestine back into the bloodstream.
From the bloodstream, urobilinogen is either recir-

CHAPTER 6—Studies

of Urine

229

Figure 6–1. Hemoglobin degradation. (From Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis, Philadelphia,
2001, p 56, with permission.)

culated to the liver and excreted with bile or excreted
via the kidneys. Normally, only a small amount of
urobilinogen is found in the urine.39
Bilirubin may be found in the urine in liver
disease and is usually found in clients who have
biliary tract obstructions. Excessive urobilinogen
may also be found in the urine of those with liver
disease or hemolytic disorders. Urobilinogen is
absent from the urine in disorders that cause
complete obstruction of the bile ducts (Table 6–4).
Bilirubinuria can occur in clients with liver
disease when the integrity of liver cells is disrupted
and conjugated bilirubin leaks into the circulation;
this leakage may be seen in hepatitis and cirrhosis. In
fact, in these disorders, bilirubin may appear in the
urine before the client actually becomes jaundiced. If
liver function is impaired such that the liver cannot
conjugate bilirubin, excessive bilirubin will not be
found in the urine. Similarly, excessive bilirubin is
not seen in the urine of clients with hemolytic disorders. These disorders have marked destruction of
red blood cells with resultant high levels of unconjugated bilirubin. The normally functioning liver is
unable to conjugate the excessive load, and although
serum levels of unconjugated bilirubin rise, urinary
bilirubin excretion remains relatively unchanged.
TABLE 6–4

•

This condition, again, is a result of the kidney’s
inability to excrete unconjugated bilirubin.
If bile duct obstruction occurs, the conjugated
bilirubin cannot pass from the biliary tract into the
intestine. Instead, excess amounts are absorbed into
the bloodstream and excreted via the kidneys. Also,
because little or no bilirubin passes into the intestine, where urobilinogen is formed, the urine will be
negative for urobilinogen. Absence of urobilinogen
in urine is associated with complete obstruction of
the common bile duct. When absence of urobilinogen is combined with the presence of blood in the
stool, carcinoma involving the head of the pancreas
may be indicated.40
As noted previously, approximately half of the
urobilinogen formed in the intestines is reabsorbed
into the bloodstream. Normally, most of this
urobilinogen is circulated to the liver, where it is
processed and excreted via bile. A smaller amount is
excreted in the urine. When liver cells are damaged,
excretion of urobilinogen in bile is decreased,
whereas its urinary excretion is increased. This
condition may be seen in clients with cirrhosis,
hepatitis, and CHF with congestion of the liver.
Excessive urobilinogen also appears in the urine
in persons with hemolytic disorders. As noted, in

Urine Bilirubin and Urobilinogen in Jaundice
Urine Bilirubin

Bile duct obstruction

Urine Urobilinogen
Normal

Liver damage

Hemolytic disease

Negative

From Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis, Philadelphia, 2001, p 57, with permission.

230

SECTION I—Laboratory

Tests

such disorders the amount of unconjugated bilirubin produced is more than the liver can handle, but
the liver attempts to compensate, and increased
amounts of urobilinogen are ultimately formed.
When this urobilinogen is recirculated back to the
liver, however, the liver is unable to process it further
and additional amounts are excreted in the urine.
A number of factors can cause spurious results
when urine is tested for bilirubin and urobilinogen.
Because excessive exposure of a urine sample to light
and room air may lead to false-negative results for
bilirubin, only fresh urine specimens should be
used. Large amounts of ascorbic acid and nitrates in
the urine also cause false-negative results. Note that
bilirubin excretion is enhanced in alkalotic states.
This also is true of urobilinogen and is a result of
decreased tubular reabsorption from alkaline urine.
Similarly, acidic urine results in decreased urinary
levels of urobilinogen. As noted, urobilinogen is
formed by bacterial action in the intestine. Broadspectrum antibiotics impair this process and result
in decreased urobilinogen production. As with
bilirubin, high levels of nitrates in the urine may also
cause false-negative results in tests for urobilinogen.41,42
NITRITE

Testing urine samples for nitrite is a rapid screening
method for determining the presence of bacteria in
the specimen. This test is based on the fact that
nitrate, which is normally present in urine, is
converted to nitrite in the presence of bacteria. The
test is performed by the dipstick method and, if
positive, indicates that clinically significant bacteriuria is present. Positive test results should always be
followed by a regular urine culture.
Several factors can interfere with the accuracy of
tests for nitrite. First, not all bacteria reduce nitrate
to nitrite. Those that do so include the gram-negative bacteria, the organisms most frequently involved
in UTIs. Because yeasts and gram-positive bacteria
may not convert nitrate to nitrite, the presence of
these organisms can cause a false-negative test result.
For bacteria to convert nitrate to nitrite, the
organisms must be in contact with urinary nitrate
for some period of time. Thus, freshly voided
random samples or urine that is withdrawn from a
Foley catheter may produce false-negative results.
The best urine samples for nitrite testing are first
morning samples from urine that has been in the
bladder overnight. Other causes of false-negative
results include inadequate amounts of nitrate in the
urine for conversion (may occur in individuals who
do not eat enough green vegetables), large amounts
of ascorbic acid in the urine, antibiotic therapy, and

excessive bacteria in the urine so that nitrite is
further reduced to nitrogen, which is not detected by
the test. False-positive reactions will occur if the
container in which the sample is collected is
contaminated with gram-negative bacteria.43,44
LEUKOCYTE ESTERASE

Testing urine samples for the presence of leukocyte
esterase is a rapid screening method for determining
the presence of certain white blood cells (i.e.,
neutrophils) in the sample and, thus, the possibility
of a UTI. This test is performed by the dipstick
method and is based on the fact that the esterases
present in neutrophils will convert the indoxyl
carboxylic acid ester on the dipstick to indoxyl,
which is converted to indigo blue by room air.
Approximately 15 minutes are needed for this reaction to take place if neutrophils are present. If positive, the test should be followed by a regular urine
culture.45
Some factors can interfere with the accuracy of
tests for leukocyte esterases. False-positive results
can occur if the sample is contaminated with vaginal
secretions.46 False-negative results can occur if high
levels of protein and ascorbic acid are present in the
urine. If the urine contains excessive amounts of
yellow pigment, a positive reaction will be indicated
by a change to green instead of blue.47

MICROSCOPIC ANALYSIS
The microscopic component of a UA involves examining the sample for formed elements, or urinary
sediment, such as red and white blood cells, epithelial cells, casts, crystals, bacteria, and mucus.
Microscopic analysis is performed by centrifuging
approximately 10 to 15 mL of urine for about 5
minutes. The resulting sediment is then examined
under the microscope. Microscopic analysis is the
most time-consuming component of the UA. It
involves both identifying and quantifying the
formed elements present.48
Note that the Addis count is a variation of the
microscopic urinalysis. For an Addis count, all urine
is collected for 12 hours and then the nature and
quantity of formed elements are determined. This
test, which was once used to follow the progress of
acute renal disease, is seldom used today, because
microscopic analysis of a single random sample
usually is sufficient.49
RED BLOOD CELLS

Red blood cells are too large to pass through the
glomerulus; thus, the finding of red blood cells in
the urine (hematuria) is considered abnormal. If red

CHAPTER 6—Studies

blood cells are present, damage to the glomerular
membrane or to the genitourinary tract is indicated.
For this test, the number of red blood cells is
counted. The result may indicate the nature and
severity of the disorder causing the hematuria.
Renal and genitourinary disorders associated with
the presence of red blood cells in the urine include
glomerulonephritis, lupus nephritis, nephritis associated with drug reactions, tumors of the kidney,
kidney stones, infections, trauma to the kidney, renal
vein thrombosis, hydronephrosis, polycystic kidney
disease, acute tubular necrosis (occasionally), and
malignant nephrosclerosis (occasionally).50
Red blood cells may also be seen with some
nonrenal disorders: acute appendicitis; salpingitis;
diverticulitis; tumors involving the colon, rectum,
and pelvis; acute systemic febrile and infectious
diseases; polyarteritis nodosa; malignant hypertension; and blood dyscrasias. Drugs that may lead to
hematuria include salicylates, anticoagulants,
sulfonamides, and cyclophosphamide. Strenuous
exercise can also cause red blood cells to appear in
the urine because of damage to the mucosa of the
bladder.51 Contamination of the sample with
menstrual blood may lead to false-positive results.
WHITE BLOOD CELLS

Normally, only a few white blood cells are found in
urine. Increased numbers of leukocytes in the urine
generally indicate either renal or genitourinary tract
disease. As with red blood cells, white blood cells
may enter the urine either through the glomerulus
or through damaged genitourinary tissues. In addition, white blood cells may migrate through undamaged tissues to sites of infection or inflammation. An
excessive amount of white blood cells in the urine is
termed pyuria.52
The most frequent cause of pyuria is bacterial
infection anywhere in the renal or genitourinary
system (e.g., pyelonephritis, cystitis). Noninfectious
inflammatory disorders, however, may also lead to
pyuria. Such disorders include glomerulonephritis
and lupus nephritis. In addition, tumors and renal
calculi may cause pyuria because of the resultant
inflammatory response.
A higher than normal number of leukocytes may
be seen if the sample is contaminated with genital
secretions. This finding is especially true in women.
White blood cells disintegrate in dilute, alkaline
urine and in samples that are allowed to stand at
room temperature for more than 1 to 2 hours.53
EPITHELIAL CELLS

Epithelial cells found in urine samples are derived
from three major sources: (1) the linings of the male

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231

and female lower urethras and the vagina (squamous epithelial cells); (2) the linings of the renal
pelvis, bladder, and upper urethra (transitional
epithelial cells); and (3) the renal tubules themselves.
Because it is normal for old epithelial cells to slough
from their respective areas, finding a few epithelial
cells in a urine sample is not necessarily abnormal.
Presence of a large numbers of cells, especially those
of renal tubular origin, is considered a pathological
situation. When large numbers of renal tubular cells
are shed, tubular necrosis is indicated. In addition to
acute tubular necrosis (ATN), excessive numbers of
tubular epithelial cells may be seen in renal transplant rejection, any ischemic injury to the kidney,
glomerulonephritis, pyelonephritis, and damage to
the kidney by drugs and toxins.54
Renal tubular epithelial cells may contain certain
lipids and pigments. Cells that contain lipoproteins,
triglycerides, and cholesterol are called oval fat
bodies. Presence of oval fat bodies occurs in lipid
nephrosis and results from lipids leaked through
nephrotic glomeruli. Histiocytes are fat-containing
cells that are larger than oval fat bodies and that
usually can be distinguished from the latter on
microscopic examination. Histiocytes may be seen
in nephrotic syndrome and in lipid-storage
diseases.55
Pigments that may be absorbed into renal tubular
epithelial cells include hemoglobin that is converted
to hemosiderin, melanin, and bilirubin.
Hemoglobin and bilirubin have been discussed
previously. Melanin may be found in tubular epithelial cells in the presence of malignant melanoma that
has metastasized to the genitourinary tract.
Finding increased epithelial cells from the lower
genitourinary tract is generally not of major clinical
significance, with one exception. If excessive
numbers of transitional epithelial cells are found in
large clumps, or sheets, carcinoma involving any
portion of the area from the renal pelvis to the bladder may be indicated.56
CASTS

Casts are gel-like substances that form in the renal
tubules and collecting ducts. They are termed casts
because they take the shape of the area of the tubule
or collecting duct in which they form. TammHorsfall protein, a mucoprotein secreted by the
distal renal tubular cells, is the major constituent of
casts. This protein forms a framework in which
other elements may be trapped (e.g., red and white
blood cells, bacteria, fats, urates). Healthy individuals may normally excrete a few casts, especially if
there is a low urinary pH, increased protein in the
urine, increased excretion of solutes, and decreased

232

SECTION I—Laboratory

Tests

rate of urine flow.57 As noted previously, proteinuria
may occur after strenuous exercise. This may lead to
the formation and excretion of an increased number
of casts in healthy individuals. Red blood cells may
also be found in casts excreted in response to such
exercise. Otherwise, excretion of an excessive
number of casts is usually associated with widespread kidney disease that involves the renal
tubules.58
Casts are classified according to the nature of the
substances present in them (Table 6–5). As can be
seen in the table, the finding of excessive numbers of
casts requires further diagnostic follow-up, because
such a condition may indicate serious renal disease.
CRYSTALS

Crystals form in urine because of the presence of the
salts from which they are precipitated. Of the
numerous types of crystals (Table 6–6), many are
not of major clinical significance. Also, several
factors affect the formation of urinary crystals: (1)
pH of the urine, (2) temperature of the urine, and
(3) concentration of the substances from which the
crystals are formed. Table 6–6 shows the pH of the
urine at which the several types of crystals are most
likely to be formed. In terms of the temperature of
the sample, crystals are most likely to be seen in
samples that have stood at room temperature for
several hours or have been refrigerated, depending
on the type of crystal. The concentration of various
substances that lead to the formation of crystals is
important in that the greater the concentration, the
greater the likelihood of precipitation of the
substance into the urine in crystal formation.
In analyzing crystals on microscopic examination,
it is important to determine the type of crystal present. The presence of certain crystals may indicate
disease states (e.g., liver disease, cystinuria). In addition, drug therapy or use of radiographic dyes can
cause precipitation of crystals that may portend
renal damage by blocking the tubules.59
OTHER SUBSTANCES

A number of other substances may be found on
microscopic urinalysis: bacteria, yeast, mucus, spermatozoa, and parasites. Bacteria are not normally
present but may be seen if UTI is present or if the
sample was contaminated externally. The number of
bacteria will increase if the specimen is allowed to
stand at room temperature for several hours.
Bacteria in the urine are generally not of major
significance unless accompanied by excessive
numbers of white blood cells, which may indicate an
infectious or inflammatory process. Yeast in the
urine usually indicates contamination of the sample

with vaginal secretions in women with yeast infections such as Candida albicans. Yeasts may also be
seen in the urine of clients with diabetes. Mucus in
urine generally reflects secretions from the genitourinary tract and is usually associated with
contamination of the sample with vaginal secretions. Spermatozoa may be found in urine after
sexual intercourse or nocturnal emissions. Parasites
are frequently of vaginal origin and may indicate
vaginitis caused by Trichomonas vaginalis. A true
urinary parasite is Schistosoma haematobium, seen in
the urine of individuals with schistosomiasis, an
uncommon disorder in the United States. If
pinworms and other intestinal parasites are found,
contamination of the sample with fecal material is
indicated.60
SUMMARY

The UA, which consists of macroscopic and microscopic components, yields a great deal of information about the client. All the tests may be performed
separately, especially those associated with macroscopic analysis. The most complete picture, however,
is obtained by synthesizing the data obtained from
the various tests.
Although a variety of disorders may be indicated
by abnormal results on a UA test, the most common
disorders indicated are the several types of renal
disease. Table 6–7 shows ways in which the results
of macroscopic and microscopic analyses are
combined to indicate certain types of renal disease.
Other types of disorders associated with abnormal
urinalysis results are listed in the indications for the
UA test.
INTERFERING FACTORS

Improper specimen collection so that the sample
is contaminated with vaginal secretions or feces
Use of collection containers contaminated with
bacteria
Therapy with medications or ingestion of foods
that may alter the color, odor, or pH of the sample
Delay in sending unrefrigerated samples to the
laboratory within 1 hour of collection, which may
lead to:
Deepening of the color of the sample
Increased alkalinity of the sample
Increased concentration of glucose, if already
present
Oxidation of bilirubin, if present, and
urobilinogen
Deterioration of urinary sediment
Multiplication of bacteria, if present
Failure to time properly those tests done by the
dipstick method (e.g., glucose and ketones)

CHAPTER 6—Studies

TABLE 6–5

•

Type
Hyaline

of Urine

233

Summary of Urine Casts
Origin

Tubular secretion of Tamm-Horsfall protein

Clinical Significance
Glomerulonephritis
Pyelonephritis
Chronic renal disease
Congestive heart failure
Stress and exercise

Red blood cell

Attachment of red blood cells to Tamm-Horsfall
protein matrix

Glomerulonephritis
Strenuous exercise
Lupus nephritis
Subacute bacterial endocarditis
Renal infarction
Malignant hypertension

White blood cell

Attachment of white blood cells to Tamm-Horsfall
protein matrix

Inflammation or infection
involving the glomerulus
Pyelonephritis
Lupus nephritis

Epithelial cell

Tubular cells remaining attached to Tamm-Horsfall
protein fibrils

Renal tubular damage

Granular

Disintegration of white cell casts

Stasis of urine flow

Bacteria

Urinary tract infection

Urates

Stress and exercise

Tubular cell lysosomes

Acute glomerulonephritis

Protein aggregates

Renal transplant rejection
Pyelonephritis
Lead poisoning

Waxy

Hyaline casts in an advanced stage of development

Stasis of urine flow
Renal transplant rejection
Renal tubular inflammation
and degeneration
Chronic renal failure
End-stage renal disease

Fatty

Renal tubular cells

Nephrotic syndrome

Broad casts

Oval fat bodies

Nephrotic syndrome

Formation in collecting ducts (i.e., casts are larger
than those formed in the tubules)

Extreme stasis of urine flow
Renal failure (severe)
Chronic glomerulonephritis

Adapted from Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis, Philadelphia, 2001, p 93.

234

SECTION I—Laboratory

TABLE 6–6

Crystal

•

Tests

Major Characteristics and Clinical Significance of
Urinary Crystals
pH

Color

Clinical Significance

NORMAL

Uric acid

Acid

Yellow-brown

Gout
Leukemias and lymphomas, especially
if client is receiving chemotherapy

Amorphous urates

Acid

Brick dust or
yellow-brown

Not of major clinical significance

Calcium oxalate

Acid/neutral
(alkaline)

Colorless
(envelopes)

High doses of ascorbic acid
Severe chronic renal disease
Ethylene glycol toxicity
Crohn’s disease, hypercalcemia

Amorphous
phosphates

Alkaline,
neutral

White
colorless

May be found in urine that has
stood at room temperature for
several hours

Calcium phosphate

Alkaline,
neutral

Colorless

Not of major clinical significance

Ammonium biurate

Alkaline

Yellow-brown
(thorny apples)

Not of major clinical significance

Calcium carbonate

Alkaline

Colorless
(dumb-bells)

Not of major clinical significance

Triple phosphate

Alkaline

Colorless
(coffin lids)

Not of major clinical significance

Cystine

Acid

Colorless

Cystinuria (inherited metabolic
defect that prevents reabsorption of
cystine by the proximal tubules)

Cholesterol

Acid

Colorless
(notched plates)

High serum cholesterol
More likely to be seen in
refrigerated specimens

Leucine

Acid/neutral

Yellow

Severe liver disease

ABNORMAL

Tyrosine

Acid/neutral

Colorless, yellow

Severe liver disease

Sulfonamides

Acid/neutral

Green

Therapy with sulfonamides

Radiographic dye

Acid

Colorless

Dye excretion

Ampicillin

Acid/neutral

Colorless

Therapy with ampicillin

Adapted from Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis, Philadelphia, 2001. pp 115–116.

INDICATIONS FOR ROUTINE URINALYSIS

The routine urinalysis is a screening technique that
is an essential component of a complete physical
examination, especially when performed on admission to a health-care facility or before surgery. It may
also be performed when renal or systemic disease is
suspected. Note that the components of a UA may be

performed separately, if necessary. This may be done
to monitor previously identified conditions. Other
indications or purposes for a UA include the following:
Detection of infection involving the urinary tract
as indicated by urine with a “fishy” or fetid odor
and presence of nitrite, leukocyte esterase, white
blood cells, red blood cells (possibly), and bacteria

TABLE 6–7

•

Laboratory Correlations in Renal Diseases

Disease

Macroscopic Examination

Acute glomerulonephritis

Macroscopic hematuria

RBCs

ASO titer ↑

Specific gravity ↑

RBC casts

GFR ↓

Protein 5 g/day

Granular casts

Sed rate ↑

Microscopic Examination

Remarks

Other Laboratory Findings

Microscopic hematuria remains
longer than proteinuria

WBCs

Macroscopic hematuria
Protein

RBCs
WBCs
Granular casts

BUN ↑
Creatinine ↑
FDP ↑
GFR ↓
Cryoglobulins ↑

Oliguria

Chronic glomerulonephritis

Macroscopic hematuria

RBCs

BUN ↑

Oliguria or anuria

Specific gravity 1.010

WBCs

Creatinine ↑

Nocturia

Protein

All types of casts
Broad casts

Serum phosphorus ↑
Serum calcium ↓

Anemia

Membranous
glomerulonephritis

Blood
Protein

RBCs
Hyaline casts

Positive ANA
Positive HBsAg

Microscopic hematuria

Membranoproliferative
(mesangioproliferative)
glomerulonephritis

Macroscopic hematuria
Protein

RBCs
RBC casts

BUN ↑
Creatinine ↑
ASO titer ↑
Complement ↓

Hematuria may be microscopic

Focal glomerulonephritis

Blood
Protein

RBCs
Fat droplets

IgA deposits on
membrane

Macroscopic or microscopic
hematuria

of Urine

(Continued on the following page )

CHAPTER 6—Studies

“Smoky” turbidity
Rapidly progressive
(crescentic)
glomerulonephritis

235

236

•

Laboratory Correlations in Renal Diseases (Continued)

Disease

Macroscopic Examination

Minimal change disease

Blood

Microscopic Examination

Other Laboratory Findings
Serum protein ↓

Oval fat bodies

Serum albumin ↓

Hematuria may be absent

Tests

RBCs

Remarks

Fat droplets
Hyaline casts
Fatty casts
Nephrotic syndrome

Protein

Oval fat bodies

Serum lipids ↑

Fat droplets

Serum protein ↓

Generalized casts

Serum albumin ↓

Heavy proteinuria 5 g/day

Waxy casts
Fatty casts
Pyelonephritis

Cloudy

WBCs

Protein

WBC casts

Nitrite

Bacteria

Leukocytes

RBCs

SECTION I—Laboratory

TABLE 6–7

Concentrating ability decreased
in chronic cases

Adapted from Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis, Philadelphia, 2001, pp 124–130.
ANAantinuclear antibody, ASOantistreptolysin O, BUNblood urea nitrogen, FDPfibrin degradation products, GFRglomerular filtration rate, HbsAghepatitis B
surface antigen, IgAimmunoglobulin A.

CHAPTER 6—Studies

of Urine

237

Reference Values
Macroscopic Analysis
Color

Pale yellow to amber

Appearance

Clear to slightly cloudy

Odor

Mildly aromatic

Specific gravity

1.001–1.035 (usual range 1.010–1.025)

4.5–8.0

Protein

Negative

Glucose

Negative

Other sugars

Negative

Ketones

Negative

Blood

Negative

Bilirubin

Negative

Urobilinogen

0.1–1.0 Ehrlich units/dL (1–4 mg/24 hr)

Nitrate

Negative

Leukocyte esterase

Negative

Microscopic Analysis
Red blood cells (RBCs)

0–3 per high-power field (HPF)

White blood cells (WBCs)

0–4 per HPF

Epithelial cells

Few

Casts

Occasional (hyaline or granular)

Crystals

Occasional (uric acid, urate, phosphate, or calcium oxalate)

Critical values: RBC 0.50, WBC, or pathological crystals, as well as grossly bloody
urine, and 3 to 41 glucose or ketones, or both

Detection of uncontrolled diabetes mellitus as
indicated by the presence of glucose and ketones
(seen primarily in insulin-dependent diabetes
mellitus) and by urine with low specific gravity
Detection of gestational diabetes during pregnancy
Detection of possible complications of pregnancy
as indicated by proteinuria
Detection of bleeding within the urinary system,
as indicated by positive dipstick test for blood and
detection of red blood cells on microscopic examination
Detection of various types of renal disease (see
Table 6–7)
Detection of liver disease as indicated by the presence of bilirubin (possibly), excessive urobilinogen, and leucine or tyrosine crystals, or both
Detection of obstruction within the biliary tree as
indicated by presence of bilirubin and absence of
urobilinogen

Detection of multiple myeloma as indicated by
the presence of Bence Jones protein
Monitoring of the effectiveness of weight-reduction diets as indicated by the presence of ketones
in the urine
Detection of excessive red blood cell hemolysis
within the systemic circulation as indicated by the
presence of free hemoglobin and elevated
urobilinogen levels
Detection of extensive injury to muscles as
indicated by the presence of myoglobin in the
urine
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That results are most reliable if the specimen is
obtained upon arising in the morning, after urine
has accumulated overnight in the bladder
(Exception: Serial urine samples for glucose
should consist of fresh urine.)

238

SECTION I—Laboratory

Tests

Nursing Alert

Improper collection and disposition of sample
for UA may lead to spurious results (see
“Interfering Factors” section). The best
samples, in general, are those that are
collected first thing in the morning after urine
has collected in the bladder overnight. The
sample should be received in the laboratory
within 1 hour of collection. If this is not
possible, the sample can be refrigerated.
The time of collection and the source of the
sample must be noted, because this information is important in evaluating the results and
in distinguishing normal from abnormal
results.
Because many drugs and foods may alter
results, a thorough medication and diet
history is necessary for evaluating the data
obtained.

The proper way to collect the sample, if the client
is to do this independently (see Appendix II)
The importance of the sample being received in
the laboratory within 1 hour of collection
Prepare for the procedure:
The client should be provided with the proper
specimen container.
For women, a clean-catch midstream kit should
be provided.
Techniques for collecting samples from children
are described in Appendix II.
For catheterized specimens, a catheterization tray
is needed if an indwelling catheter is not already
present.
THE PROCEDURE

A voided or catheterized sample of approximately 15
mL is collected (see Appendix II).
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include observing
the color, clarity, and odor of the sample when it is
obtained. Perform dipstick tests for glucose, ketones,
protein, and blood on separate portions of the
sample, if desired.
Hydration state: Note and report intake and
output (I&O) ratio and adequacy, changes in
urinary pattern and diuresis, and dehydration and
fluid shifts. Monitor I&O and effect on specimen
collection and testing, urinary sample characteristics and amount, and urinary pattern changes.

Correct techniques: Store dipsticks in a dry, cool,
dark place. Immerse dipstick in the urine for an
appropriate time and examine in a well-lit place
after an appropriate time interval. Confirm all
abnormal test results.
Specific gravity: Note and report increases over
1.020. Monitor I&O. Assess for dehydration.
Administer additional fluids, if allowed. Note
decreases below 1.009. Monitor I&O and weight
for fluid overload. Assess for renal dysfunction.
Inform and instruct client in fluid intake necessary to maintain adequate hydration.
pH: Note and report increases over 6 (alkaline
urine). Assess for risk of or presence of UTI or
renal calculi. Increase fluid intake and restrict
foods that leave an alkaline ash (milk, citrus
fruits). Administer ordered vitamin C. Note
decreases below 6 (acid urine). Administer
medications to promote an alkaline urine. Assess
for possible metabolic or respiratory acidotic
states.
Protein: Note and report any trace or range of
protein from 0 to 41 or 10 to 1000 mg/dL. Collect
another specimen and test or prepare the client
for an ordered 24-hour urine analysis.
Glucose: Note and report any trace or range of
glucose from 0 to 41. Assess blood glucose level.
Also assess for drugs that cause elevations,
increased urinary output and thirst, or possible
dehydration state. Prepare for further testing for
glucose levels in the blood and urine.
Ketones: Note and report moderate acetone level
and blood level over 50 mg/dL. Assess weight,
dietary regimen, diarrhea, presence of diabetes
mellitus, or possible ketoacidotic state. Administer ordered insulin or other medications.
Blood: Note and report microscopic or macroscopic amounts of blood. Assess for anticoagulant
therapy, urinary tract or renal disorders, or toxic
response to drug therapy.
Bilirubin: Note and report presence of bilirubin.
Assess for jaundice of mucous membranes and
sclera and for clay color of stool. Also assess for
liver or biliary tract disorders and drug regimens
that cause liver damage.
Nitrite: Note and report positive result. Obtain a
clean-catch urine specimen for culture tests.
Leukocyte esterase: Note and report positive
results with a positive nitrite test. Obtain a cleancatch urine specimen for culture tests.
Critical values: Physician should be notified
immediately of a positive microscopic result of
high levels of red blood cells, greater than 50
white blood cells, or pathological crystals, as
well as grossly bloody urine, and 3 to 41 or 1 to

CHAPTER 6—Studies

2 percent of glucose or ketones, or both, by
dipstick testing.

TESTS OF RENAL FUNCTION
Renal function tests are used to evaluate the excretory, secretory, and osmolar regulation dynamics of
the kidney. Broad categories of such tests include (1)
clearance tests, (2) tubular function tests, and (3)
concentration tests.

CLEARANCE TESTS AND CREATININE
CLEARANCE
The term clearance refers to the relationship between
the renal excretory mechanisms and the circulating
blood levels of the materials to be excreted.
Clearance reflects the overall efficiency of glomerular functioning.
Substances filtered through the glomerulus are
(1) excreted into the urine unaltered by the renal
tubules, (2) reabsorbed partially or entirely by the
renal tubules, or (3) added to by the renal tubules.
For the purpose of clearance tests, substances that
pass through the glomerulus and are not altered by
the renal tubules are analyzed. The assumption is
that all of the substance is cleared from the plasma
via the glomerulus and is excreted unchanged into
the urine. Substances that may be measured in clearance tests include inulin, urea, para-aminohippuric
acid (PAH), and creatinine.61
Inulin is an inert sugar that is not metabolized,
absorbed, or secreted by the body. To determine
renal clearance, inulin must be infused IV at a
constant rate throughout the testing period. Renal
clearance is then calculated by measuring the
urinary excretion of inulin in relation to plasma
concentration. Because this test involves administration of an exogenous substance, it is not used
frequently.62 PAH is similar to inulin in that it also
must be administered IV for clearance tests.
Urea, an end product of protein metabolism, is
formed in the liver and excreted relatively
unchanged by the kidneys. Blood urea levels are
affected by a variety of factors, and, therefore, it is
not the ideal substance for renal clearance tests.
Blood urea levels may be elevated if shock, trauma,
sepsis, or tumors cause increased protein metabolism. A high-protein diet or state of dehydration will
also cause elevated blood urea levels. High blood
urea levels could result in normal clearance test
values even though renal function is depressed.
Creatinine is the ideal substance for determining
renal clearance because a fairly constant quantity is
produced within the body. As discussed in Chapter

of Urine

239

5, creatinine is the end product of creatine metabolism. Creatine resides almost exclusively in skeletal
muscle, where it participates in energy-requiring
metabolic reactions. In these processes, a small
amount of creatine is irreversibly converted to creatinine, which then circulates to the kidneys and is
excreted. The amount of creatinine generated in an
individual is proportional to the mass of skeletal
muscle present and remains fairly constant unless
there is massive muscle damage caused by crushing
injury or degenerative muscle disease.63 Because
muscle mass is usually greater in men than in
women, the quantity of creatinine excreted is usually
greater in men.
Creatinine clearance is a sensitive indicator of
glomerular function because those factors affecting
creatinine clearance are primarily caused by alterations in renal function. These factors include the
number of functioning nephrons, the efficiency with
which they function (i.e., if there is decreased functioning of some nephrons, others may function
more efficiently to compensate), and the amount of
blood entering the nephrons. In general, a 50 percent
reduction in functioning nephrons causes creatinine
clearance to be slightly decreased. Loss of two-thirds
of the nephrons, however, produces a sharp
decrease. Note that creatinine clearance tends to
decline with normal aging. Thus, it is important to
know the client’s age when interpreting test results.64
Renal disease is the major cause of reduced creatinine clearance. Other disorders that can result in
decreased creatinine clearance include shock, hypovolemia, and exposure to nephrotoxic drugs and
chemicals.
The creatinine clearance test is performed by
collecting all urine for 24 hours, measuring the creatinine present, and calculating clearance according
to the basic formula shown here. As indicated by the
formula, it is necessary to determine the plasma level
of creatinine at some point during the test.
C UV
P
where
C creatinine clearance
U amount of creatinine in urine
V volume of urine excreted per 24 hours
P plasma creatinine level
INTERFERING FACTORS

Incomplete urine collection may yield a falsely
lowered value.
Excessive ketones in urine and presence of
substances such as barbiturates, phenolsulfon-

240

SECTION I—Laboratory

Tests

Reference Values
Creatinine Clearance

Conventional Units

SI Units

Men

85–125 mL/min

1.41–2.08 mL/s/1.73 m2

Women

75–115 mL/min

1.21–1.91 mL/s/1.73 m2

phthalein, and sulfobromophthalein (Bromsulphalein [BSP]) may cause falsely lowered values.
INDICATIONS FOR CLEARANCE TESTS AND
CREATININE CLEARANCE

Determination of the extent of nephron damage
in known renal disease (i.e., at least 50 percent of
functioning nephrons must be lost before values
will be decreased)
Monitoring for the effectiveness of treatment in
renal disease
Determination of renal function before administering nephrotoxic drugs or drugs that may build
up if glomerular filtration is reduced
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The necessity of collecting all urine for 24 hours
How to maintain the sample (e.g., on ice, refrigerated) if being collected at home
That a blood sample also will be collected once
during the test
Prepare for the procedure:
Provide the proper collection container.
Provide for proper preservation of the sample.
Use the techniques for collecting a 24-hour
sample as described in Appendix II.
THE PROCEDURE

Creatinine Clearance. A 24-hour urine sample is
collected (see Appendix II). A preservative may be
added to the collection container by the laboratory
to prevent degradation of the creatinine. If a preservative is not available, the urine should be kept on ice
or refrigerated throughout the collection period. A
blood sample is obtained at some point during the
urine collection to determine plasma creatinine level.
NURSING CARE AFTER THE PROCEDURE

Special aftercare interventions are not required for
this test.
Compromised renal function: Note and report
creatinine clearance that has decreased in
comparison to an increased serum creatinine and
estimated GFR. Monitor I&O and fluid and
protein restrictions. Instruct client in dietary,
fluid, and medication inclusions and exclusions.

TUBULAR FUNCTION TESTS AND
PHENOLSULFONPHTHALEIN TEST
Tubular function tests assess the ability of the renal
tubules to remove waste products and other
substances (e.g., drugs) from the blood and secrete
them into the urine. Normal tubular function is
dependent on two main factors: (1) adequate renal
blood flow and (2) effective tubular function.
According to Sacher and McPherson,65 although
tests of tubular function may provide valuable
physiological insight, they provide little diagnostic
information in individual clinical situations.
More appropriate information may be obtained by
measuring blood and urine levels of substances
such as glucose and electrolytes and comparing
the results. Elevated serum potassium levels, for
example, combined with decreased potassium in the
urine indicate impaired tubular secretion of potassium. Failure to excrete an appropriate acidic or
alkaline urine in relation to blood pH levels also
indicates disruption of normal tubular secreting
mechanisms.
If tubular function tests are to be performed, they
are usually carried out by injecting phenolsulfonphthalein (PSP) IV and then measuring its excretion
in serial urine samples. PSP is a dye that binds to
albumin in the bloodstream and, therefore, cannot
be excreted through the glomerulus. To be excreted,
the dye must be secreted by renal tubular cells. In the
proximal renal tubules, the dye has greater affinity
for the cells lining the tubules than it does for the
protein. When it dissociates from the protein, it can
be secreted by the tubules.66 Because it is a dye, PSP
imparts a pinkish color to alkaline urine upon excretion. Within 2 hours of injection, 75 percent of the
dose is excreted if renal blood flow and tubular function are normal.
Measurement of the dye that is present is accomplished with a spectrophotometer. Thus, any
substances that alter the color of urine (see Table
6–1) may also alter test results. The client must be
well hydrated so that renal perfusion is adequate and
urine flow is brisk. If the urine lacks sufficient alkalinity, substances such as sodium hydroxide may be
added to the sample in the laboratory to produce the
necessary pH for testing.

CHAPTER 6—Studies

of Urine

241

Reference Values
Adults

After 15 min, 25% of the dose is excreted
After 30 min, 50–60% of the dose is excreted
After 60 min, 60–70% of the dose is excreted
After 2 hr, 70–80% of the dose is excreted

Children

Amounts excreted are 5–10% higher at the preceding time intervals

INTERFERING FACTORS

Failure to collect the urine samples at the required
times (Reference Values are based on these times.)
Failure to completely empty the bladder each time
a specimen is collected
Presence in the urine of any substance that alters
the color of urine (see Table 6–1), because results
are based on dye excretion
Inadequately hydrated client such that the kidneys
are inadequately perfused or urine flow is
decreased
Presence in the blood of radiographic dye, salicylates, sulfonamides, and penicillin that may lead
to decreased excretion of the dye
High serum protein levels, which may lead to
decreased excretion of the dye
Severe hypoalbuminemia, excessive albuminuria,
or severe liver disease, which may lead to
increased excretion of the dye
INDICATIONS FOR TUBULAR FUNCTION TESTS
AND PHENOLSULFONPHTHALEIN TEST

Assessment of renal blood flow and tubular
secreting ability (The PSP test is of limited clinical
usefulness.)
Nursing Alert

The PSP excretion test should not be
performed on clients who have demonstrated
previous allergy to the dye.
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The importance of increased fluid intake before
the test
That foods and drugs that impart color to the
urine (e.g., carrots, beets, rhubarb, azo drugs)
should be avoided for 24 hours before the test
That a dye that circulates through the blood and
then is excreted by the kidneys will be injected IV
That four urine specimens will be obtained at
timed intervals (i.e., 15 minutes, 30 minutes, 1
hour, and 2 hours) after injection of the dye

The importance of completely emptying the bladder each time a urine sample is obtained
Obtain a signed permission consent form. Then:
Ensure to the extent possible that dietary and
medication restrictions are followed.
Provide sufficient fluids to promote adequate
hydration.
Obtain four containers for the urine samples.
THE PROCEDURE

PSP Excretion Test. PSP dye is injected IV, after
which a pressure dressing is applied to the injection
site. Urine samples are then collected at 15-minute,
30-minute, 1-hour, and 2-hour intervals. Each specimen should consist of at least 50 mL. If the client
cannot void at the required time, a Foley catheter
may be inserted and the specimen obtained. The
catheter is then clamped until the next specimen
is due.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include resuming
any withheld foods and medications.
Monitor the dye injection site for inflammation
and hematoma formation.
Remove a catheter if one has been inserted for the
test, and assess voiding pattern.
Allergic response: Note and report skin rash,
urticaria, and change in pulse and respirations.
Administer ordered antihistamine and steroid
therapy. Have resuscitation equipment and
oxygen on hand.
Urinary infection: Note and report urinary
pattern changes and characteristics (cloudy, foul
smelling). Obtain urine specimen for culture.
Monitor I&O. Administer antimicrobial therapy
as ordered.

CONCENTRATION TESTS AND
DILUTION TESTS
Concentration tests assess the ability of the renal
tubules to appropriately absorb water and essential
salts such that the urine is properly concentrated.
The glomerular filtrate entering the renal tubules

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normally has a specific gravity of 1.010. If the renal
tubules are damaged such that they cannot effectively reabsorb water and salt, the specific gravity of
the excreted urine will remain at 1.010. Loss of tubular concentrating ability is one of the earliest indicators of renal disease and may occur before blood
levels of urea and creatinine rise. In addition to the
various forms of renal disease, other situations in
which renal concentrating ability may be impaired
include failure to secrete antidiuretic hormone
(central diabetes insipidus), lack of renal response to
antidiuretic hormone (nephrogenic diabetes
insipidus), prolonged overhydration, osmotic diuresis (especially that caused by uncontrolled diabetes
mellitus), hypokalemia, hypocalcemia, lithium and
ethanol use, severe hypoproteinemia, multiple
myeloma, amyloidosis, sickle cell disease or trait, and
psychogenic polydipsia.
The concentration of urine may be determined by
measuring either the specific gravity or the osmolality of the sample. In some cases, a single early-morning specimen will suffice. In other situations, timed
tests conducted over 12 to 24 hours may be necessary. Another approach is to measure both the serum
and the urine osmolality and to compare the results.
Measuring the osmolality of urine is considered
more accurate than determining the specific gravity.
As noted previously, both the number and the size of
particles present influence the specific gravity of
urine. In contrast, osmolality is affected only by the
number of particles present. Thus, smaller molecules such as sodium and chloride, which are of
interest in renal concentration tests, contribute more
to urine osmolality measures than they do to specific
gravity determinations. In the laboratory, osmolality
is reported as milliosmols (mOsm).
Normally, the kidneys can concentrate urine to an
osmolality of about three to four times that of
plasma (normal plasma osmolality is 275 to 300
mOsm). If the client is overhydrated, the kidneys
will excrete the excess water and produce urine with
an osmolality as low as one-fourth or less that of
plasma.67 Because factors such as fluid intake, diet
(especially protein and salt intake), and exercise
influence urine osmolality, it has been difficult to
establish exact reference values. It is considered
more reliable to measure serum and urine osmolalities and compare the two in terms of a ratio relationship (see Chapter 5).
Timed concentration tests are performed if earlymorning samples indicate inadequate overnight
urine concentrating ability. In the Fishberg test, an
attempt is made to maximally concentrate urine
through fluid restriction. In the standard version of
this test, the client consumes no fluid for 24 hours

(from breakfast one day to breakfast the next). In the
simplified version, fluids are restricted from the
evening meal until breakfast the next morning (see
“The Procedure” later in this section).68 The 24hour fluid restriction should produce the maximum
concentration possible. The 12-hour overnight
restriction will increase the concentration to about
75 percent of maximum, partly because of the
normal increase in urine concentration that occurs
at night.69
The Mosenthal test also derives from the principle
of increased urine concentration at night. In this
test, two consecutive 12-hour urine specimens are
collected, one from approximately 8 AM to 8 PM and
one from 8 PM to 8 AM. If kidney function is normal,
the specific gravity of the nighttime collection
should be greater than that of the daytime collection.70
Note that tests of the kidney’s ability to produce
dilute urine are rarely performed. These tests involve
overhydrating the client and then observing for the
appearance of dilute urine with low specific gravity
and osmolality. The danger is that not all clients can
tolerate the fluid load needed to produce the desired
results.
INTERFERING FACTORS

Concentration Tests
Failure of the client to follow the fluid restrictions
necessary for the Fishberg test
Ingestion of a diet with an excessive or inadequate
amount of protein, sodium, or both
Presence of disorders that alter serum protein or
sodium levels
Dilution Tests
Inability of the client to ingest the required fluids
for the test
Inability of the client to tolerate the fluid load
required for the test
INDICATIONS FOR CONCENTRATION TESTS
AND DILUTION TESTS

Concentration Tests
Early detection of renal tubular damage (i.e.,
before serum levels of urea and creatinine are
elevated) as indicated by loss of tubular concentrating ability
Detection of disorders that impair renal concentrating ability (e.g., diabetes insipidus)
Differentiation of psychogenic polydipsia from
organic disease as indicated by a normal response
to timed concentration tests (e.g., Fishberg test)
Detection of excessive or prolonged overhydration

CHAPTER 6—Studies

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243

Reference Values
Concentration Tests
Specific gravity

1.001–1.035 (usual range 1.010–1.025)

Osmolality

50–1400 mOsm (usual range 300–900 mOsm; average 850 mOsm)

Ratio of urine to
serum osmolality

1.2:1 to 3:1

Fishberg test (standard)

Specific gravity 1.026 or higher on at least one sample

Fishberg test (simplified)

Specific gravity 1.022 or higher on at least one sample

Mosenthal test

Specific gravity 1.020 or higher with at least a 7-point
difference between the specific gravities of the daytime and nighttime
samples

Dilution Tests
Specific gravity

1.003

Osmolality

100 mOsm

Determination of decreased osmolality (overhydration) and increased osmolality (dehydration)
Dilution Tests
Evaluation of renal tubular response to high fluid
volume as indicated by production of urine with
low specific gravity and osmolality
Nursing Alert

Dilution tests should not be performed on
clients who may have difficulty tolerating an
increased fluid load (e.g., clients with CHF).

NURSING CARE BEFORE THE PROCEDURE

Urine Osmolality
There is no specific preparation other than reviewing with the client when the specimen is to be
obtained (e.g., first-voided morning urine) and
providing a collection container.
Fishberg Test (Standard Version)
Explain to the client:
That no fluids are to be taken after breakfast the
initial morning of the test until the test is
completed the next morning
That solid (dry) foods are not restricted
That client should completely empty the bladder
at approximately 10 PM before retiring
That client should remain in bed during the night
(i.e., during the usual hours of sleep)
That a urine specimen will be obtained at 8 AM
after 24 hours without fluids

That client should return to bed for 1 hour after
the first specimen is collected
That a second specimen will be collected at 9 AM
That client should resume normal activity for 1
hour after the second specimen is collected
That a third specimen will be collected at 10 AM
Prepare for the procedure:
Ensure to the extent possible that fluid restrictions
are followed.
Provide the proper specimen containers.
Fishberg Test (Simplified Version)
Explain to the client:
That no fluids should be taken from the time of
the evening meal until the test is completed
That client should completely empty the bladder
at approximately 10 PM before retiring
That urine samples will be collected at 7 AM, 8 AM,
and 9 AM, after approximately 12 hours without
fluids
Note: Some laboratories require that the evening
meal consist of a high-protein, low-salt diet with no
more than 200 mL fluid. If this is the case, the client
should be so informed. Then:
Ensure to the extent possible that fluid restrictions
are followed.
Provide the proper specimen containers.
Mosenthal Test
Explain to the client:
That two consecutive 12-hour urine collections
will be obtained: one from 8 AM to 8 PM in one
container and one from 8 PM to 8 AM in another
container

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The importance of collecting all urine voided
during the time period
That there are no diet or fluid restrictions
Prepare for the procedure:
Provide the proper specimen containers.
Dilution Tests
Explain to the client:
That it will be necessary to drink approximately
3 pt (1500 mL) of water in a 1/2-hour period
That hourly urine specimens will be obtained for
4 hours after ingestion of the water
That any symptoms of fluid excess (e.g., palpitations, shortness of breath) should be reported
immediately
Ensure to the extent possible that the client
consumes or receives the required fluids. Then:
Provide the proper specimen containers.
THE PROCEDURE

Specific Gravity and Urine Osmolality. A random
urine specimen of at least 15 mL is collected, preferably first thing in the morning.

NURSING CARE AFTER THE PROCEDURE

Specific Gravity and Urine Osmolality. There are
no special aftercare interventions.
Fishberg Tests. Resume normal fluid intake and
diet.
Mosenthal Test. There are no special aftercare
interventions.
Dilution Tests. Monitor response to the fluid load.
Note especially increased pulse rate or difficulty
breathing.
Hydration state: Note and report I&O ratio and
adequacy, changes in urinary pattern, and diuresis. Assess for dehydration signs and symptoms.
Monitor I&O and effect on specimen collection
and testing. Also monitor urinary amounts and
characteristics.
Critical values: Notify physician immediately if
the osmolality result is less than 100 mOsm
(overhydration) or greater than 800 mOsm
(dehydration).

Fishberg Test (Standard Version). The client eats
his or her usual breakfast, after which no further
fluids are ingested until the test is completed the
next morning. Solid (dry) foods are allowed. The
client voids at approximately 10 PM or before retiring. Urine specimens are collected the next morning
at 8 AM, 9 AM, and 10 AM. The client is to remain in
bed between the 8 AM and 9 AM specimens and to
resume normal activities between the 9 AM and 10
AM specimens.

MEASUREMENT OF OTHER
SUBSTANCES

Fishberg Test (Simplified Version). The client eats
his or her evening meal, after which no fluids are
ingested until the test is completed the next morning. Some laboratories require that the evening
meal consist of a high-protein, low-salt diet with no
more than 200 mL of fluid. The client voids at
approximately 10 PM or before retiring. Urine
samples are collected the next morning at 7 AM,
8 AM, and 9 AM.

One of the major functions of the kidney is the regulation of electrolyte balance. Electrolytes are filtered
through the glomerulus and reabsorbed in the renal
tubules. Those electrolytes most commonly measured in urine are sodium, chloride, potassium,
calcium, phosphorus, and magnesium. Tests for
electrolytes in urine usually involve 24-hour urine
collections. Serum determinations of electrolyte
levels are, therefore, preferred to the more cumbersome urinary determinations (see Chapter 5). An
exception is magnesium, which indicates deficiency
earlier than does serum assay.

Mosenthal Test. Two separate but consecutive 12hour urine collections are obtained, one from 8 AM
to 8 PM and one from 8 PM to 8 AM the next day.
Dilution Tests. These tests, although rarely
conducted, may be performed upon completion of
the Fishberg tests. The client ingests 1500 mL of
water over a 1/2-hour period. An alternative
approach is to administer IV fluids, with the type
and amount determined by the physician ordering
the test. Urine samples are collected every hour for 4
hours after ingestion or administration of the fluid.

A variety of substances can be measured in urine to
detect alterations in physiological function. Among
these are electrolytes, pigments, enzymes, hormones
and their metabolites, proteins and their metabolites, and vitamins and minerals.

ELECTROLYTES

SODIUM

Most of the sodium filtered through the glomerulus
is reabsorbed in the proximal renal tubule.
Additional amounts may be reabsorbed in the distal
tubule under the influence of aldosterone, a
hormone (mineralocorticoid) released by the adrenal cortex. Aldosterone is released in response to
decreased serum sodium, decreased blood volume,

CHAPTER 6—Studies

and increased serum potassium. Enhanced sodium
reabsorption is reflected in decreased amounts being
excreted in the urine. This may be seen in situations
such as hyperaldosteronism, hemorrhage, shock,
CHF with inadequate renal perfusion, and therapy
with adrenal corticosteroids. Increased loss of
sodium into the urine is associated with excessive
salt intake, diuretic therapy, diabetic ketoacidosis,
adrenocortical hypofunction, toxemia of pregnancy,
hypokalemia, and excessive licorice ingestion. Renal
failure may cause either retention or loss of sodium.
In acute renal disease involving the renal tubules
(e.g., ATN), excessive loss of sodium into the urine
may occur, because the tubules are too impaired to
reabsorb sodium normally.
CHLORIDES

Chlorides are generally reabsorbed passively along
with sodium. The kidney may also secrete either
chloride or bicarbonate, depending on the acid–base
balance of the body. Chloride excretion is directly
influenced by chloride intake. It is also influenced by
factors that affect sodium excretion. Chloride excretion may be impaired in certain types of renal
disease.71
POTASSIUM

Like sodium, potassium is filtered through the
glomerulus and reabsorbed through the tubules.
Adequate excretion of potassium from the body also
requires that the distal tubules and collecting ducts
secrete potassium into the urine. Aldosterone also
influences potassium excretion in that potassium is
excreted in exchange for the sodium that is reabsorbed. Urinary excretion also varies in relation to
dietary intake. Causes of excessive potassium loss in
the urine include diabetic ketoacidosis, therapy with
diuretics, and consumption of large amounts of
licorice. The most common cause of decreased
potassium in the urine is chronic renal failure, in
which tubular secretory activity is impaired.
CALCIUM

Calcium is the most abundant cation in the body,
with bone its major reservoir. Only a small amount
of calcium circulates in the blood, and most calcium
excretion takes place via the stools. Serum calcium
levels are largely regulated by the parathyroid glands
and vitamin D. Urinary calcium excretion varies
directly with the serum calcium level. If blood levels
are high, more calcium is excreted. Blood levels of
calcium vary with dietary intake, although they are
more influenced by increased intake than by
decreased intake. Calcium excretion is highest just
after a meal and lowest at night.72 Although many

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245

disorders may alter calcium excretion, determination of urinary calcium is made primarily to evaluate individuals with kidney stones or with suspected
parathyroid disorders.
Seventy-five percent of all kidney stones contain
calcium compounds. Contrary to popular belief, the
most common cause of calcium-containing kidney
stones is not excessive calcium intake. The hypercalcemia and increased calcium excretion associated
with calcium kidney stones are the result of lack of
appropriate renal tubular reabsorption of calcium,
increased calcium reabsorption in the intestines, loss
of calcium from bone, or low serum phosphorus
levels. A variety of disorders can cause these basic
defects,73 among them hyperparathyroidism;
sarcoidosis; renal tubular acidosis; cancers of the
lung, breast, and bone; multiple myeloma; and
metastatic cancer. Drugs that may lead to excessive
calcium excretion include toxic doses of vitamin D,
adrenocorticosteroids, and calcitonin.
Decreased calcium in the urine is related to
hypoparathyroidism, nephrosis, acute nephritis,
chronic renal failure, osteomalacia, steatorrhea, and
vitamin D deficiency. Drugs associated with
decreased calcium in the urine are thiazides and
viomycin.
As noted, a 24-hour urine collection is made to
determine the quantity of calcium lost in the urine.
Sulkowitch’s test, a qualitative measure, can be used
to determine the presence of calcium in random
urine specimens. If necessary, clients may be taught
to perform this test at home.
PHOSPHORUS

As with calcium, serum contains relatively small
amounts of phosphorus, with bone serving as the
major reservoir. Phosphorus levels also are regulated
by the parathyroid glands and vitamin D, with excretion controlled primarily by the kidneys. Causes of
increased loss of phosphorus in the urine include
hyperparathyroidism and renal tubular acidosis.
Causes of decreased loss in the urine are
hypoparathyroidism, nephrosis, nephritis, and
chronic renal failure. Toxic doses of vitamin D may
also result in decreased urinary excretion of phosphorus. Dietary intake of phosphates also influences
urinary excretion.
MAGNESIUM

Magnesium is an essential nutrient found in bone,
muscle, and red blood cells. Relatively little is found
in serum. Magnesium participates in the control of
serum electrolyte levels and increases intestinal
absorption of calcium. Signs and symptoms of
magnesium imbalance are manifested primarily in

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the central nervous and neuromuscular systems.
Urinary measures of magnesium may be used
instead of serum measures because changes in
magnesium levels are reflected more quickly in the
urine than in the blood and may facilitate prompt
diagnosis of the client’s problem. Causes of
increased magnesium excretion include alcoholism,
adrenocortical insufficiency, renal insufficiency,
hypothyroidism, hyperparathyroidism, and excessive ingestion of magnesium-containing antacids.
Thiazide diuretics and ethacrynic acid may also
produce excessive urinary excretion of magnesium.
Decreased urinary excretion is associated with
malabsorption syndromes, dehydration, hyperaldosteronism, diabetic acidosis, pancreatitis, and
advanced chronic renal disease. Increased calcium
intake also results in decreased urinary excretion of
magnesium.
INTERFERING FACTORS

antacids may lead to increased excretion of
magnesium.
INDICATIONS FOR MEASUREMENT OF URINARY
ELECTROLYTES

With the exception of magnesium, electrolytes are
more likely to be measured by serum determinations
than by urinary measures of the substances. General
reasons for analyzing electrolytes in urine are as
follows:
Suspected renal disease
Suspected endocrine disorder
History of kidney stones
Suspected malabsorption problem
Central nervous system (CNS) signs and symptoms of unknown etiology, especially if thought to
be a result of magnesium imbalance, which is
detected earlier in urine than in blood
NURSING CARE BEFORE THE PROCEDURE

Dietary deficiency or excess of the electrolyte to
be measured may lead to spurious results.
Increased calcium intake may result in decreased
magnesium excretion.
Increased sodium and magnesium intake may
cause increased calcium excretion.
Diuretic therapy with excessive loss of electrolytes
into the urine may falsely elevate results.
Therapy with adrenocorticosteroids may lead to
decreased sodium loss and increased calcium loss.
Excessive ingestion of magnesium-containing

For quantitative studies (i.e., studies to determine the
amount of the electrolyte present), client preparation
is the same as that for any test involving the collection of a 24-hour urine sample (see Appendix II).
For calcium studies, some laboratories require
that the client be on a diet with a set amount of
calcium for at least 3 days before beginning the
urine collection. If this is the case, the client
should be instructed about the diet.
Medications are not usually withheld, but the
laboratory should be informed about those taken.

Reference Values
Conventional Units

SI Units

Sodium

30–280 mEq/24 hr

30–280 mmol/day

Chloride

110–250 mEq/24 hr 110–250 mmol/day

Potassium

40–80 mEq/24 hr

40–80 mmol/day

Men

275 mg/24 hr

6.8 mmol/day

Women

250 mg/24 hr

6.2 mmol/day

Calcium
Quantitative

Qualitative
Sulkowitch’s test 0 to 2 turbidity
Phosphorus

0.9–1.3 g/24 hr

Magnesium

150 mg/24 hr
6.0–8.5 mEq/24 hr
3.0–4.3 mmol/day

29–42.0 mmol/day

CHAPTER 6—Studies

If the Sulkowitch test, a qualitative study, is used
for home monitoring of urinary calcium, the
client should be instructed in the procedure.
THE PROCEDURE

Quantitative Tests. A 24-hour urine collection is
obtained (see Appendix II). Check with the laboratory or individual ordering the test to see whether
the diet is to be modified for calcium studies. The
laboratory should be informed of any medications
taken by the client that may alter test results (see
“Interfering Factors” section).
Qualitative Tests (Sulkowitch’s Test). A random
urine specimen is obtained, 5 mL of which is poured
into a test tube. Acetic acid (5 mL of a 10 percent
solution) is added to the sample and the mixture is
boiled to remove protein. Distilled water is then
added to the sample until the original volume is
restored. Sulkowitch’s reagent (5 mL), which
contains oxalic acid and ammonium oxalate, is then
added. This reagent reacts with the calcium in the
sample and produces turbidity (cloudiness) in the
sample. Turbidity is graded on a scale of 0 to
14.74.74,75
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include resuming
the client’s diet after the specimen collection is
completed.

PIGMENTS
Pigments that may be found in urine consist primarily of those substances involved in the synthesis
and breakdown of hemoglobin. These substances
consist of hemoglobin, hemosiderin, bilirubin,
urobilinogen, and porphyrins. Myoglobin, which is
related to hemoglobin but found primarily in skeletal muscle, is another type of pigment, as is melanin,
which is found in hair and skin. With the exceptions
of urobilinogen and porphyrins, these substances
are not normally found in urine.
Hemoglobin, hemosiderin, bilirubin, and
urobilinogen were previously discussed, as was
myoglobin. The presence of myoglobin is associated
with extensive damage to skeletal muscles. Melanin,
which may be incorporated into tubular epithelial
cells, is seen in malignant melanoma. The focus of
this section, therefore, is on the porphyrins.
PORPHYRINS

Porphyrins are produced during the synthesis of
heme (Fig. 6–2). If heme synthesis is deranged, these
precursors accumulate and are excreted in the urine

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247

in excessive amounts. Conditions producing
increased levels of heme precursors are called
porphyrias. The two main categories of genetically
determined porphyrias are erythropoietic porphyrias, in which major diagnostic abnormalities occur
in red cell chemistry, and hepatic porphyrias, in
which heme precursors are found in urine and feces.
Erythropoietic and hepatic porphyrias are very rare.
Acquired porphyrias are characterized by greater
accumulation of precursors in urine and feces than
in red blood cells. Lead poisoning is the most
common cause of acquired porphyria.
Those porphyrins for which urine may be tested
include aminolevulinic acid (ALA), porphobilinogen (PBG), uroporphyrin, and coproporphyrin.
Knowing the type of porphyrin excreted in excess
aids in diagnosing specific disorders. Tests for
porphyrins usually involve collection of 24-hour
urine samples to determine the quantity of the
specific substance present. Screening tests on
random specimens to determine the presence of
excessive amounts of porphyrins (i.e., qualitative
studies) also are available.
The presence of ALA in the urine is associated
with lead poisoning. It is also found in liver disease
(e.g., hepatic carcinoma and hepatitis) and in acute
intermittent and variegate porphyria. PBG is found
in the same disorders and may also be seen in clients
taking griseofulvin. Rifampin, elevated urobilinogen, and light exposure can falsely elevate values.
Uroporphyrin and coproporphyrin also are seen in
clients with lead poisoning and liver disease as well
as in those with uroporphyria and porphyria
cutanea tarda. Uroporphyrin may be found in
hemochromatosis, a disorder of iron metabolism
that affects the liver and certain other body organs.
Coproporphyrin is associated with obstructive jaundice and exposure to toxic chemicals.
Porphyrins are reddish fluorescent compounds.
Depending on the type of porphyrin present, therefore, the urine may be reddish or the color of port
wine (see Table 6–1). The presence of congenital
porphyria may be suspected when an infant’s wet
diaper shows a red discoloration. PBG is excreted as
a colorless compound. If a sample containing PBG is
acidic and is exposed to air for several hours,
however, a color change may occur.76
INTERFERING FACTORS

For random samples, delay in sending the specimen to the laboratory within 1 hour of collection
may lead to oxidation of bilirubin, if present, and
of urobilinogen; random samples for porphyrin
tests must be fresh and, thus, must be sent to the
laboratory immediately upon collection.

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Figure 6–2. Pathway of heme
formation, including stages
affected by the major disorders
of porphyrin metabolism. (From
Strasinger, SK: Urinalysis and
Body Fluids, ed 4. FA Davis,
Philadelphia, 2001, p 142, with
permission.)

For 24-hour samples, failure to collect the specimen in a dark container or in a container covered
with aluminum foil or a dark plastic bag can result
in invalid results. The specimen must also be
refrigerated or kept on ice throughout the collection period unless a preservative has been added
to the container by the laboratory. (If the client
has a Foley catheter, the drainage bag must be
covered with a dark plastic bag and placed in a
basin of ice.)
Therapy with griseofulvin, rifampin, and barbiturates may falsely elevate values in tests for
porphyrins.

INDICATIONS FOR ANALYSIS OF URINARY
PIGMENTS

Detection of liver disease as indicated by the presence of bilirubin (possible), excessive urobilinogen, and elevated porphyrins
Diagnosis of the source of obstructive jaundice
(i.e., obstruction in the biliary tree) as indicated
by the presence of bilirubin, absence of urobilinogen, and elevated coproporphyrins
Detection of suspected lead poisoning as indicated by elevated porphyrins, especially ALA and
PBG

CHAPTER 6—Studies

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249

Reference Values
Conventional Units

SI Units

Hemoglobin

Negative

Hemosiderin

Negative

Bilirubin

Negative

Urobilinogen
Random specimen
24-hr urine

0.1–1.0 Ehrlich U/dL

Negative

1–4 mg/24 hr

Myoglobin

Negative

Melanin

Negative

Porphyrins
Aminolevulinic acid
38.1 mol/L

Random specimen
Children

0.5 mg/dL

Adults

0.1–0.6 mg/dL

24-hr urine

7.6–45.8 mol/L

1.5–7.5 mg/dL/24 hr

11.15–57.2 mol/day

Porphobilinogen
Random specimen
24-hr urine

Negative

Negative
0–66 mol/day

0–1.5 mg/24 hr

Uroporphyrin
Random specimen

Negative

24-hr urine

10–30 g/24 hr
(Values may be slightly higher
in men than in women.)

12–37 nmol/day

Coproporphyrin
Random specimen
Adults

0.045–0.30 mol/L

24-hr urine
Children
Adults

0–80 g/24 hr

0–0.12 mol/day

50–160 g/24 hr
(Values may be slightly higher
in men than in women.)

Detection of excessive red blood cell hemolysis
within the systemic circulation as indicated by the
presence of free hemoglobin, elevated urobilinogen levels, and presence of hemosiderin a few days
after the acute hemolytic episode
Detection of extensive injury to muscles as indicated by the presence of myoglobin in the urine
Detection of malignant melanoma as indicated by
the presence of melanin in the urine

0.075–0.24 mol/day

NURSING CARE BEFORE THE PROCEDURE

For quantitative studies, client preparation is the
same as that for any test involving collection of a 24hour urine sample (see Appendix II).
The client should receive the proper container
and instructions for maintaining the collection
(e.g., refrigerated, protected from light).
For studies involving the porphyrins, medications

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Tests

such as griseofulvin, rifampin, and barbiturates
may be withheld. This practice should be
confirmed with the person ordering the test.
For random samples, there is no specific preparation other than informing the client that the
sample must be protected from light and sent
to the laboratory within 1 hour of collection.
The proper container should be provided to the
client.
THE PROCEDURE

Quantitative Tests. A 24-hour urine collection is
obtained in a dark container or in one covered with
aluminum foil or a dark plastic bag. The sample
must be kept refrigerated or on ice throughout the
collection period unless a preservative has been
added to the container by the laboratory. If the client
has a Foley catheter, the drainage bag must be
covered with a dark plastic bag and placed in a basin
of ice.
Random Specimens (Qualitative Tests). A random
sample is collected and sent promptly (within 1
hour) to the laboratory. The specimen must be
protected from excessive exposure to light.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the tests include resuming
any withheld medications after the specimen collection has been completed.

ENZYMES
As noted in Chapter 5, enzymes are catalysts that
enhance reactions without directly participating in
them. Enzymes are normally intracellular molecules.
When the cells and tissues in which these molecules
are found are damaged, enzymes are released and
increased levels are found in the blood and the
urine. Because some enzymes are specific to only
certain tissues, elevated levels may aid in pinpointing
the source of pathophysiological problems.
Although many enzymes can be measured in
blood, only a few are analyzed in urine, including
amylase, arylsulfatase A, lysozyme (muramidase),
and leucine aminopeptidase. All studies of urinary
enzymes involve the collection of 24-hour urine
samples, with the exception of amylase, which may
be evaluated in timed specimens over shorter periods of time (e.g.,1 or 2 hours).
AMYLASE

Amylase is a digestive enzyme that splits starch into
disaccharides such as maltose. Although many cells
have amylase activity, amylase circulating in serum

(and ultimately excreted in urine) derives from the
parotid glands and the pancreas. Unlike many other
enzymes, amylase activity is primarily extracellular;
it is secreted into saliva and the duodenum, where it
splits large carbohydrate molecules into smaller
units for further digestive action by intestinal
enzymes.
Urinary amylase levels generally parallel the levels
found in blood. There is, however, a lag time
between the rise of blood levels and urinary levels.
Elevated urine levels also return to normal more
slowly than blood levels. This difference between
blood and urinary levels of amylase aids in diagnosing and monitoring disorders associated with
elevated amylase levels.
ARYLSULFATASE A

Arylsulfatase A (ARS A) is a lysosomal enzyme
found in all body cells except mature red blood cells.
Its main sites of activity are in the liver, pancreas,
and kidney.
LYSOZYME (MURAMIDASE)

Lysozyme is a bactericidal enzyme present in tears,
saliva, mucus, and phagocytic cells. Lysozyme is
produced in granulocytes and monocytes.
LEUCINE AMINOPEPTIDASE

Leucine aminopeptidase (LAP) is an isoenzyme of
alkaline phosphatase, an enzyme that cleaves phosphate from compounds and is optimally active at a
pH of 9. Although widely distributed in body tissues,
LAP is most abundant in hepatobiliary tissues,
pancreas, and small intestine.
INTERFERING FACTORS

Incomplete specimen collection and improper
specimen maintenance may lead to spurious
results.
Amylase
Ingestion of drugs that may falsely elevate values
(morphine, codeine, meperidine, pentazocine,
chlorothiazides, aspirin, corticosteroids, oral contraceptives, alcohol, indomethacin, bethanechol
[Urecholine], secretin, and pancreozymin)
Inadvertent addition of salivary amylase to the
sample because of coughing or talking over it
may falsely elevate values.
Arylsulfatase A
Contamination of the sample with blood, mucus,
and feces may falsely elevate levels.
Abdominal surgery within 1 week of the collection may falsely elevate levels.

CHAPTER 6—Studies

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251

Reference Values

Amylase

Conventional Units

SI Units

10–80 amylase U/hr (Mayo Clinic)

265–680 U/day*

35–260 Somogyi U/hr

SI U/hr
6.5–48.1*

Arylsulfatase A
Children

1 U/L

Men

1.4–19.3 U/L

Women

1.4–11 U/L

Lysozyme (muramidase)

1.3–3.6 mg/24 hr

Leucine aminopeptidase

2–28 U/24 hr

* These values reflect routine testing methods used in many laboratories, not those under the Conventional
Units heading.

Lysozyme (Muramidase)
Presence of bacteria in the sample, which will
falsely decrease levels
Presence of blood and saliva in the sample, which
will falsely elevate levels
Leucine Aminopeptidase
Advanced pregnancy and therapy with drugs
containing estrogen and progesterone may falsely
elevate levels.
INDICATIONS FOR URINARY ENZYME TESTS

Amylase
Retrospective diagnosis of acute pancreatitis
when serum amylase levels have returned to
normal but urine levels remain elevated for 7 to
10 days77
Diagnosis of chronic pancreatitis revealed by
persistently elevated urinary amylase levels
Monitoring for response to treatment for pancreatitis
Assistance in identifying the cause of “acute
abdomen”
Differentiation between acute pancreatitis and
perforated peptic ulcer (Urinary amylase levels
are higher in pancreatitis.)
Diagnosis of macroamylasemia, a disorder seen in
alcoholism and malabsorption syndromes, as
revealed by elevated serum amylase and normal
urinary amylase
Confirmation of the diagnosis of salivary gland
inflammation
Arylsulfatase A
Suspected malignancy involving the bladder,

colon, or rectum as indicated by elevated
levels
Suspected granulocytic leukemia as indicated by
elevated levels
Family history of lipid storage diseases (e.g.,
mucolipidoses II and III), with support for the
diagnosis indicated by elevated levels
Suspected metachromatic leukodystrophy as indicated by decreased levels
Lysozyme (Muramidase)
Suspected acute granulocytic or monocytic
leukemia as indicated by elevated levels
Monitoring for the extent of destruction of
monocytes and granulocytes in known leukemias
Suspected renal tubular damage as indicated by
elevated levels
Monitoring of response to renal transplant with
rejection indicated by elevated levels78
Leucine Aminopeptidase
Elevated serum alkaline phosphatase or LAP
levels of unknown etiology
Suspected liver (cirrhosis, hepatitis, cancer),
pancreatic (pancreatitis, cancer), and biliary
diseases (obstruction caused by gallstones, strictures, atresia), especially when serum LAP levels
are normal (Urinary elevations lag behind serum
elevations.)
NURSING CARE BEFORE THE PROCEDURE

Amylase. Client preparation is the same as that for
any study involving a 24-hour or timed urine collection (see Appendix II). The proper container and
instructions for maintaining the collection (e.g.,

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refrigerated, protected from exposure to salivary
secretions) should be provided.
Drugs that may alter test results (see “Interfering
Factors” section) may be withheld during the test,
although this practice should be confirmed with
the person ordering the study.
Arylsulfatase A. Client preparation is the same as
that for any study involving a 24-hour urine collection. The proper container and instructions for
maintaining the collection (e.g., refrigerated, placed
on ice) should be provided.
Lysozyme (Muramidase). Client preparation is the
same as that for any study involving a 24-hour urine
collection. The proper container and instructions
for maintaining the collection (e.g., refrigerated,
placed on ice) should be provided. The client
should be cautioned to avoid touching the inside
of the collection container to avoid bacterial
contamination of the sample. The client also should
be cautioned to avoid contaminating the sample
with saliva (e.g., coughing over the specimen) or
blood.
Leucine Aminopeptidase. Client preparation is the
same as that for any study involving a 24-hour urine
collection. The proper container and instructions
for maintaining the collection (e.g., refrigerated,
placed on ice) should be provided. Because drugs
containing estrogens and progesterone may falsely
elevate levels, a medication history regarding these
types of drugs should be obtained.
THE PROCEDURE

Amylase. A timed urine collection is obtained. The
collection may be made over 1-, 2-, 6-, 8-, and 24hour periods. The sample must be kept refrigerated
or on ice throughout the collection period unless the
laboratory has added a preservative to the container.
If the client has a Foley catheter, the drainage bag
must be placed in a basin of ice. Care must be taken
to avoid adding salivary secretions to the sample by
coughing or talking over the specimen. The sample
should be sent promptly to the laboratory when the
collection is completed.
Arylsulfatase A. A 24-hour urine collection is
obtained. The sample must be kept refrigerated or
on ice throughout the collection period unless a
preservative has been added to the container by the
laboratory. If the client has a Foley catheter, the
drainage bag must be placed in a basin of ice. Care
must be taken not to contaminate the sample with
blood, mucus, or feces. The sample should be sent
promptly to the laboratory when the collection is
completed.

Lysozyme (Muramidase). A 24-hour urine collection is obtained. The sample must be kept refrigerated or on ice throughout the collection period
unless a preservative has been added to the container
by the laboratory. If the client has a Foley catheter,
the drainage bag must be placed on ice. Care must be
taken not to contaminate the sample with bacteria,
blood, or saliva. The sample should be sent promptly
to the laboratory when the collection is completed.
Leucine Aminopeptidase. A 24-hour urine collection is obtained. The sample must be kept refrigerated or on ice throughout the collection period
unless a preservative has been added to the container
by the laboratory. If the client has a Foley catheter,
the drainage bag must be placed on ice. The sample
should be sent promptly to the laboratory when the
collection is completed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include resuming
any withheld medications after the specimen collection has been completed.

HORMONES AND THEIR METABOLITES
Hormones are chemicals that control the activities
of responsive tissues. Some hormones exert their
effects in the vicinity of their release; others are
released into the extracellular fluids of the body and
affect distant tissues. Numerous hormones can be
measured in blood (see Chapter 5). Most urinary
measures focus on the hormones secreted by the
adrenal cortex, the adrenal medulla, the gonads, and
the placenta. Either the hormone itself or the
metabolites thereof can be measured.
Urinary measures of hormones and their metabolites usually involve collection of 24-hour urine
specimens. The advantage of such quantitative
measures over single blood level determinations is
that overall levels of hormone secretion are reflected.
This is important because blood levels of hormones
tend to vary, depending on time of day.
CORTISOL

The adrenal cortex secretes three types of steroids:
(1) glucocorticoids, which affect carbohydrate
metabolism; (2) mineralocorticoids, which promote
potassium excretion and sodium retention by the
kidneys; and (3) adrenal androgens, which the liver
converts primarily to testosterone. Cortisol is the
predominant glucocorticoid. It is produced and
secreted in response to adrenocorticotropic
hormone (ACTH), which is secreted by the adenohypophysis. Ninety percent of cortisol is bound to

CHAPTER 6—Studies

cortisol-binding globulin (CBG) and albumin. The
“free” (unbound) portion is responsible for its physiological activity and also is the portion excreted into
the urine. Cortisol stimulates gluconeogenesis,
mobilizes fats and proteins, antagonizes insulin, and
suppresses inflammation.
The purpose of urinary measures of cortisol is to
detect elevated levels of free cortisol, which may not
be apparent in random blood samples. Elevated
cortisol levels occur in Cushing’s syndrome, in
which there is excessive production of adrenocorticosteroids. Cushing’s syndrome may be caused by
pituitary adenoma, adrenal hyperplasia, benign or
malignant adrenal tumors, and nonendocrine
malignant tumors that secrete ectopic ACTH.
Therapy with adrenal corticosteroids may also
produce cushingoid signs and symptoms. Elevated
cortisol levels are additionally associated with stress,
hyperthyroidism, obesity, diabetic ketoacidosis,
pregnancy, and excessive exercise. Other drugs that
may elevate cortisol levels include estrogens, oral
contraceptives, lithium carbonate, methadone, alcohol, phenothiazines, amphetamines, morphine, and
reserpine.
ALDOSTERONE

Aldosterone, the predominant mineralocorticoid, is
secreted by the zona glomerulosa of the adrenal
cortex in response to decreased serum sodium,
decreased blood volume, and increased serum
potassium. Aldosterone is released in response to
direct stimulation by altered serum sodium and
potassium levels. In addition, decreased blood
volume and altered sodium and potassium levels
stimulate the juxtaglomerular apparatus of the
kidney to secrete renin. Renin is subsequently
converted to angiotensin II, which then stimulates
the adrenal cortex to secrete aldosterone. In normal
states, ACTH does not play a major role in aldosterone secretion. In disease states, however, ACTH
may also enhance aldosterone secretion.
Aldosterone increases sodium reabsorption in the
renal tubules, gastrointestinal tract, salivary glands,
and sweat glands. This subsequently results in
increased water retention, blood volume, and blood
pressure. Aldosterone also increases potassium
excretion by the kidneys in exchange for the sodium
ions that are retained.
Excessive aldosterone levels are categorized as
primary and secondary hyperaldosteronism.
Primary hyperaldosteronism represents inappropriate aldosterone secretion, which is usually caused by
benign adenomas or bilateral hyperplasia of the
aldosterone-secreting zona glomerulosa cells. In
primary aldosteronism, aldosterone is secreted inde-

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253

pendently of the renin–angiotensin system. A hallmark of primary aldosteronism is low plasma renin
levels.
Secondary hyperaldosteronism indicates an
appropriate response to pathological changes in
blood volume and electrolytes. Common causes of
secondary hyperaldosteronism include CHF, cirrhosis, nephrotic syndrome, chronic obstructive
pulmonary disease (COPD), and renal artery stenosis. Other causes of elevated aldosterone levels are
stress, excessive exercise, pregnancy, and several
drugs (diuretics, Apresoline, diazoxide, and nitroprusside). In secondary hyperaldosteronism, plasma
renin levels are elevated.
Decreased aldosterone levels are associated with
Addison’s disease, hypernatremia, hypokalemia,
diabetes mellitus, toxemia of pregnancy, excessive
licorice ingestion, and certain drugs (propranolol
and fludrocortisone).

17-HYDROXYCORTICOSTEROIDS
All glucocorticoids are degraded by the liver to
metabolites, which as a group are called 17-hydroxycorticosteroids (17-OHCS). These steroid metabolites also are called Porter-Silber chromogens
because of the method used to measure them in
urine. Because 80 percent of urinary 17-OHCS are
metabolites of cortisol, those disorders that are associated with elevated cortisol levels also are associated
with elevated 17-OHCS (e.g., Cushing’s syndrome).
Decreased levels of 17-OHCS are associated with
Addison’s disease, hypopituitarism, and myxedema.
As with cortisol, numerous drugs may alter urinary
excretion of 17-OHCS. Thus, a thorough medication history is necessary. Some medications may be
withheld before and during the test.
When adrenocortical hypofunctioning or hyperfunctioning is suspected, 17-OHCS may be measured in urine as part of the diagnostic process. Note,
however, that measurement of urinary cortisol levels
provides more accurate quantification than does
measurement of 17-OHCS levels in individuals
receiving drugs that alter hepatic metabolism of
steroids.

17-KETOSTEROIDS
17-Ketosteroids (17-KS) are metabolized from
androgenic hormones. In men, two-thirds of 17-KS
originate in the adrenal cortex and one-third derive
from the testes. In women, virtually all 17-KS originate in the adrenal cortex. 17-Ketosteroids do not
include testosterone. Components of 17-KS, which
can be measured individually, include androsterone,
dehydroepiandrosterone, etiocholanolone, 11hydroxyandrosterone, 11-hydroxyetiocholanolone,

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SECTION I—Laboratory

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11-ketoandrosterone, 11-ketoetiocholanolone, pregnanediol, pregnanetriol (see following section), 5pregnanetriol, and 11-ketopregnanetriol.
Levels of 17-KS are elevated in clients having
adrenogenital syndrome (congenital adrenal hyperplasia), Cushing’s syndrome, hormone-secreting
tumors of the adrenal glands or gonads, adrenocortical carcinoma, hyperpituitarism, and stressful
conditions. Decreased levels of 17-KS are associated with Addison’s disease, liver disease, hyopituitarism, hypothyroidism, gout, nephrotic
syndrome, and starvation. As with other urinary
hormones, drugs may alter the excretion of 17KS. Thus, a thorough medication history is necessary.

17-KETOGENIC STEROIDS
Cortisol and its many metabolites can be manipulated in the laboratory to form 17-ketosteroids. The
substances thus formed are called 17-ketogenic
steroids (17-KGS) and can be studied as an index of
overall glucocorticoid metabolism. Before urinary
17-KGS can be evaluated, the 17-KS of androgenic
origin must be either removed or measured separately.79 Because such a large array of steroid
metabolites is reflected in 17-KGS measures, this test
provides for a good overall assessment of adrenal
function.
PREGNANETRIOL

Pregnanetriol is a metabolite of the cortisone
precursor 17-hydroxyprogesterone. It should not be
confused with pregnanediol, which is a metabolite of
the hormone progesterone, secreted by the corpus
luteum and the placenta (see preceding discussion).
Elevated pregnanetriol levels are associated with
adrenogenital syndrome. In this disorder, cortisol
synthesis is impaired at the point of 17-hydroxyprogesterone conversion. The substance accumulates and its metabolite, pregnanetriol, is excreted in
the urine in increased amounts. Excessive amounts
of 17-hydroxyprogesterone, and the resultant pregnanetriol, are produced in response to feedback
mechanisms. Because cortisol synthesis is impaired,
serum cortisol levels are low. This, in turn, stimulates the adenohypophysis to secrete ACTH, which
normally causes cortisol levels to rise. Because cortisol synthesis is impaired, however, pregnanetriol
accumulates instead. Furthermore, the feedback
mechanism continues to stimulate ACTH production. Note that excessive 17-hydroxyprogesterone
can be converted to androgens. This conversion plus
excessive androgen secretion in response to ACTH
may result in virilization in women and in sexual
precocity in boys.

CATECHOLAMINES

The adrenal medulla, a component of the sympathetic nervous system, secretes epinephrine and
norepinephrine, which are collectively known as the
catecholamines. A third catecholamine, dopamine, is
secreted in the brain, where it functions as a neurotransmitter. Dopamine is a precursor of epinephrine
and norepinephrine. Serotonin, an amine related to
the catecholamines, is found in the platelets and in
the argentaffin cells of the intestines.
Epinephrine (adrenalin) and norepinephrine are
normally secreted in response to generalized sympathetic nervous system stimulation. Epinephrine
increases the metabolic rate of all cells, heart rate,
arterial blood pressure, blood glucose, and free fatty
acids. Norepinephrine, the predominant catecholamine, decreases heart rate while increasing
peripheral vascular resistance and arterial blood
pressure.
The most clinically significant disorder involving
the adrenal medulla is the catecholamine-secreting
tumor, pheochromocytoma. Pheochromocytomas
may release catecholamines—primarily epinephrine—continuously or intermittently. For this
reason, urinary measurements are helpful in quantifying overall excretory levels. Because the most
common sign of pheochromocytoma is arterial
hypertension, measurement of either plasma (see
Chapter 5) or urinary catecholamines and their
metabolites is indicated in new-onset hypertension
of unknown etiology.
Total catecholamines can be measured in either
random or 24-hour urine specimens. The individual
catecholamines, epinephrine and norepinephrine,
can be measured in 24-hour urine collections, as can
metanephrine, a metabolite of epinephrine.
Numerous drugs may alter blood and urine levels of
catecholamines, and stress, smoking, and strenuous
exercise may produce elevated levels. Thus, a thorough health history is required before testing.
VANILLYLMANDELIC ACID

Vanillylmandelic acid (VMA) is the predominant
catecholamine metabolite found in urine. VMA is
easier to detect by laboratory methods than are the
catecholamines themselves. Therefore, this test is
frequently used when pheochromocytoma is
suspected.
A disadvantage of the test is the need for a special
diet for 2 days before the study as well as on the day
the 24-hour urine specimen is collected. The following foods are restricted on a “VMA diet”: bananas,
nuts, cereals, grains, tea, coffee, gelatin foods, citrus
fruits, chocolate, vanilla, cheese, salad dressing, jelly,

CHAPTER 6—Studies

candy, chewing gum, cough drops, most carbonated
beverages, licorice, and foods with artificial flavoring
or coloring. Ingestion of such foods will falsely
elevate VMA levels. Note, however, that, as laboratory methods become more precise, it may be possible to dispense with the VMA diet in urinary
measures of VMA.80
HOMOVANILLIC ACID

Homovanillic acid (HVA) is a metabolite of
dopamine, a major catecholamine itself, as well as a
precursor to the catecholamines epinephrine and
norepinephrine. HVA is synthesized in the brain and
is associated with disorders involving the nervous
system. As with other metabolites, numerous drugs,
stress, and excessive exercise may alter HVA levels.

5-HYDROXYINDOLEACETIC ACID
5-Hydroxyindoleacetic acid (5-HIAA) is a metabolite of serotonin, which is normally present only in
the platelets and in the argentaffin cells of the intestines.
ESTROGENS AND ESTROGEN FRACTIONS

Estrogens are secreted in large amounts by the
ovaries and, during pregnancy, by the placenta.
Minute amounts are secreted by the adrenal glands
and, possibly, by the testes. Estrogens induce and
maintain the female secondary sex characteristics,
promote growth and maturation of the female
reproductive organs, influence the pattern of fat
deposition that characterizes the female form, and
cause early epiphyseal closure. They also promote
retention of sodium and water by the kidneys and
sensitize the myometrium to oxytocin.
Total estrogens as well as the estrogen fractions
(estrone, estradiol, and estriol) can be measured in
urine. In blood tests, only the fractions are routinely
measured (see Chapter 5). Estrone (E1) is the immediate precursor of estradiol (E2), which is the most
biologically potent fraction. Estriol (E3), in addition
to ovarian sources, is secreted in large amounts by
the placenta during pregnancy. It is also secreted by
maternal and fetal adrenal glands. Normally, estriol
levels should rise steadily during pregnancy.
In addition to advancing and multiple pregnancy,
elevated estrogen levels are associated with ovarian
and adrenal tumors as well as estrogen-producing
tumors of the testes. Drugs that elevate estrogen
levels include estrogen-containing drugs, adrenocorticosteroids, tetracyclines, ampicillin, and phenothiazines.
Decreased estrogen levels are seen with primary
and secondary ovarian failure, Turner’s syndrome,
hypopituitarism, adrenogenital syndrome, Stein-

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255

Leventhal syndrome, anorexia nervosa, and
menopause. Low or steadily decreasing levels of
estriol during pregnancy may indicate placental
insufficiency, impending fetal distress, fetal anomalies (e.g., anencephaly), and Rh isoimmunization.
Decreased estriol levels are also associated with
diabetes, hypertensive disorders, and other maternal
complications of pregnancy.
Note that, in ovulating women, estrogen levels
vary in relation to the menstrual cycle. Thus, the
date of the last menstrual period should be noted
when analysis of urinary estrogens is performed.
PREGNANEDIOL

Pregnanediol is the chief metabolite of progesterone,
which is secreted by the corpus luteum and by the
placenta during pregnancy. Progesterone also is
secreted in minute amounts by the adrenal cortex in
both men and women. Progesterone prepares the
endometrium for implantation of the fertilized
ovum, decreases myometrial excitability, stimulates
proliferation of the vaginal epithelium, and stimulates growth of the breasts during pregnancy. During
pregnancy, after implantation of the embryo, progesterone production increases, thus sustaining the
pregnancy. This increased production continues
until about the 36th week of pregnancy, after which
levels begin to diminish.
Although serum determination of progesterone
can be made (see Chapter 5), the study of its
metabolite, pregnanediol, in urine reflects overall
progesterone levels, which may not be apparent in
single blood measures. In addition to pregnancy,
elevated pregnanediol levels may be associated with
ovarian tumors and cysts, adrenocortical hyperplasia and tumors, precocious puberty, and therapy
with adrenocorticosteroids. Biliary tract obstruction
may also produce elevated levels.
Decreased levels of pregnanediol are associated
with placental insufficiency, fetal abnormalities
or demise, threatened abortion, and toxemia of
pregnancy. Other causes of decreased levels include
panhypopituitarism, ovarian failure, Turner’s
syndrome, adrenogenital syndrome, and SteinLeventhal syndrome. Therapy with drugs containing
progesterone may also lead to decreased pregnanediol levels.
In ovulating women, pregnanediol levels vary in
relation to the menstrual cycle. Thus, the date of the
last menstrual period should be noted when analysis
of pregnanediol is performed.
HUMAN CHORIONIC GONADOTROPIN

Human chorionic gonadotropin (hCG) is produced
only by the developing placenta, and its presence in

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blood (see Chapter 5) and urine has been used for
decades to detect pregnancy. Human chorionic
gonadotropin is secreted at increasingly higher levels
during the first 2 months of pregnancy, declining
during the third and fourth months, and then
remaining relatively stable until term.
Qualitative screening test kits for hCG are available for home use to determine pregnancy as early as
8 to 10 days after conception. These screening kits
have almost eliminated quantitative testing for hCG
to confirm pregnancy. A positive result indicates that
a visit to a physician is necessary to obtain confirmation tests and prenatal care, and a negative result
in the presence of symptoms of pregnancy indicates
that a visit to a physician is necessary for further
evaluation.
Elevated levels may be seen in nonendocrine
tumors that produce hCG ectopically (e.g., carcinomas of the stomach, liver, pancreas, and breast;
multiple myeloma; and malignant melanoma).
Decreased levels of hCG are associated with ectopic
pregnancy, fetal demise, threatened abortion,
and incomplete abortion. Drugs that may alter
test results include phenothiazines and anticonvulsants.
INTERFERING FACTORS

Improper specimen collection and improper
specimen maintenance may lead to spurious
results.
Numerous drugs may alter test results. A thorough medication history should be obtained
before testing. Some medications may be withheld.
Cortisol
Excessive exercise and stressful situations during
the testing period may lead to falsely elevated
levels.
Aldosterone
Ingestion of certain foods may lower levels (e.g.,
licorice and excessive sodium intake).
Excessive exercise and stressful situations during
the testing period may falsely elevate levels.
Radioactive scans within 1 week of the study may
alter results because urinary aldosterone determinations are made by radioimmunoassay method.
17-Hydroxycorticosteroids
Excessive exercise and stressful situations during
the testing period may falsely elevate levels.
17-Ketosteroids
Blood in the specimen may alter test results; the
test should be postponed if the female client is
menstruating.

Excessive exercise and stressful situations during
the testing period may falsely elevate levels.
17-Ketogenic Steroids
Excessive exercise and stressful situations during
the testing period may falsely elevate levels.
Pregnanetriol
None, except drugs and improper specimen
collection and maintenance
Catecholamines
Excessive exercise and stressful situations during
the testing period may falsely elevate levels.
Vanillylmandelic Acid
Numerous foods may falsely elevate levels; the
client must follow a special diet for this test.
Excessive exercise and stressful situations during
the testing period may falsely elevate levels.
Homovanillic Acid
Excessive exercise and stressful situations during
the testing period may falsely elevate levels.
5-Hydroxyindoleacetic Acid
Certain foods (bananas, plums, pineapples, avocados, eggplants, tomatoes, and walnuts) will falsely
elevate levels and must be withheld for 4 days
before the test.81
Severe gastrointestinal disturbance or diarrhea
may alter test results.
Estrogens and Estrogen Fractions
Maternal disorders (e.g., hypertension, diabetes,
anemia, malnutrition, hemoglobinopathy, liver
disease, intestinal disease) may result in decreased
estriol levels during pregnancy.
Threatened abortion, ectopic pregnancy, and
early pregnancy may result in falsely decreased
estriol levels.
Pregnanediol
None, except drugs and improper specimen
collection and maintenance
Human Chorionic Gonadotropin
Proteinuria and hematuria may lead to falsely
elevated levels.
INDICATIONS FOR MEASUREMENT OF URINARY
HORMONES AND THEIR METABOLITES

Cortisol
Diagnostic evaluation of signs of Cushing’s
syndrome without definitive elevation of plasma
cortisol levels (Adrenal hyperplasia raises the
urinary cortisol level more significantly than it
does the plasma cortisol level.)
Diagnostic evaluation of obesity of undetermined

CHAPTER 6—Studies

of Urine

257

Reference Values
Conventional Units
Cortisol
Aldosterone

20–90 g/24 hr
2–26 g/24 hr

SI Units
55–230 mol/day
5.6–72 nmol/day

17-Hydroxycorticosteroids
Children

1.5–4.0 mg/24 hr (age related: the younger
the child, the less hormone secreted)

Men

5.5–14.4 mg/24 hr

15.2–39.7 mol/day

Women

4.9–12.9 mg/24 hr

13.5–35.6 mol/day

4.1–11.0 mol/day

17-Ketosteroids
Children

1–3 mg/24 hr (age related: the younger
the child, the less hormone secreted)

3–10 mol/day

Men

8–25 mg/24 hr

27–85 mol/day

Women

5–15 mg/24 hr

17–52 mol/day

Elderly persons

4–8 mg/24 hr

13.5–28 mol/day

17-Ketogenic steroids
Children

2–6 mg/24 hr (age related: the younger
the child, the less hormone secreted)

6–17 mol/day

Men

5–23 mg/24 hr

17–80 mol/day

Women

3–15 mg/24 hr

10–52 mol/day

Elderly persons

3–12 mg/24 hr

10–42 mol/day

Pregnanetriol
Children, 6 yr

Up to 0.2 mg/24 hr

0.6 mol/day

Children, 7–16 yr

0.3–1.1 mg/24 hr

0.9–3.3 mol/day

Adults

3.5 mg/24 hr

10.4 mol/day

Catecholamines
Total
Random urine

0–14 g/dL

0.73 nmol/day

24-hour urine

100 g/24 hr

160 nmol/day

Epinephrine

10 ng/24 hr

55 nmol/day

Norepinephrine

100 ng/24 hr

591 nmol/day

Metanephrine

0.1–1.6 mg/24 hr

0.5–8.7 mol/day

0.7–6.8 mg/24 hr

3–34 mol/day

0–25 mg/24 hr

1–126 mol/day

Vanillylmandelic acid (VMA)
Homovanillic acid (HVA)
Children
1–2 yr
2–10 yr

0.5–10 mg/24 hr

3–55 mol/day

10–15 yr

0.5–12 mg/24 hr

3–66 mol/day

258

SECTION I—Laboratory

Tests

Reference Values (continued)
Conventional Units
Adult
5-Hydroxyindoleacetic acid

8 mg/24 hr
2–9 mg/24 hr

SI Units
1–14 mol/day
10.4–46.8 mol/day

Estrogens
Total
4–24 g/24 hr

4–24 g/day

5–25 g/24 hr

5–25 g/day

Ovulatory phase

24–100 g/24 hr

24–100 g/day

Luteal phase

12–80 g/24 hr

12–80 g/day

Adult men
Nonpregnant women
Preovulatory phase

Postmenopausal women

10 mg/24 hr

10 mg/day

Estrone
Children

0.2–1 g/24 hr

0.7–4 nmol/day

Men

3.4–8.2 g/24 hr

12–37 nmol/day

Early in cycle

4–7 g/24 hr

1.6–3.5 mmol/mol

Luteal phase

11–31 g/24 hr

4.6–15.7 mmol/mol

Nonpregnant women

Postmenopausal women

0.8–7.1 g/24 hr

Estradiol
Children

0–0.2 g/24 hr

0–0.69 nmol/day

Men

0–0.4 g/24 hr

0–1.39 nmol/day

Early in cycle

0–3 g/24 hr

0–10.4 nmol/day

Luteal phase

4–14 g/24 hr

Nonpregnant women

Postmenopausal women

0–2.3 g/24 hr

13.9–49.6 nmol/day
0–8.0 nmol/day

Estriol
Children

0.3–2.4 g/24 hr

1.04–8.33 nmol/day

Men

0.8–7.5 g/24 hr

2.8–26.0 nmol/day

Early in cycle

0–15 g/24 hr

0–52.0 nmol/day

Luteal phase

13–54 g/24 hr

6.1–187.4 nmol/day

Nonpregnant women

Postmenopausal women

0.6–6.8 g/24 hr

2.08–23.6 nmol/day

Pregnant women

Up to 28 mg/24 hr (When
plotted on a graph, levels
should steadily rise during
pregnancy.)

Up to 97 mol/day

CHAPTER 6—Studies

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259

Reference Values
Conventional Units

SI Units

Pregnanediol
Men

1.5 mg/24 hr

4.7 mol/day

0.5–1.5 mg/24 hr

1.6–4.7 mol/day

2–7 mg/24 hr

6.2–22 mol/day

0.2–1 mg/24 hr

0.6–3.1 mol/day

Nonpregnant women
Proliferative phase
Luteal phase
Postmenopausal women
Pregnant women
16 wk

5–21 mg/24 hr

15–65 mol/day

20 wk

6–26 mg/24 hr

18–81 mol/day

24 wk

12–32 mg/24 hr

37–100 mol/day

28 wk

19–51 mg/24 hr

59–160 mol/day

32 wk

22–66 mg/24 hr

68–206 mol/day

36 wk

22–77 mg/24 hr

40–240 mol/day

40 wk

23–83 mg/24 hr

72–197 mol/day

Human chorionic gonadotropin
Random urine

Negative if not pregnant

Men

Not measurable

Nonpregnant women

Not measurable

1st trimester

Up to 500,000 IU/24 hr

Up to 500,000 IU/L6

2nd trimester

10,000–25,000 IU/24 hr

10,000–25,000 IU/L6

3rd trimester

5,000–15,000 IU/24 hr

5,000–15,000 IU/L6

24-hr urine

Pregnant women

etiology (Obesity may raise plasma cortisol levels
but does not significantly elevate free cortisol
levels in urine.)
Quantification of cortisol excess, regardless of its
source
More accurate quantification than 17-OHCS in
individuals receiving drugs that alter hepatic
metabolism of steroids
Aldosterone
Suspected hyperaldosteronism, especially when
serum aldosterone levels are not definitive for the
diagnosis
17-Hydroxycorticosteroids
Signs and symptoms of adrenocortical hypofunctioning or hyperfunctioning

Suspected Cushing’s syndrome as indicated by
elevated levels
Suspected Addison’s disease as indicated by
decreased levels
17-Ketosteroids
Suspected adrenocortical dysfunction, especially
if urinary levels of 17-OHCS are normal
Suspected Cushing’s syndrome as indicated by
elevated levels
Suspected adrenogenital syndrome as indicated
by elevated levels
Monitoring of response to therapy for adrenogenital syndrome
17-Ketogenic Steroids
Suspected adrenal hypofunctioning or hyperfunc-

260

SECTION I—Laboratory

Tests

tioning (The test provides a good overall assessment of adrenal function.)
Suspected Cushing’s syndrome as indicated by
elevated levels
Suspected Addison’s disease as indicated by
decreased levels
Monitoring for response to therapy with corticosteroid drugs or other drugs that alter adrenal
function

Detection of placental and fetal problems as indicated by estriol levels that fail to show a steady
increase over several days or weeks (A sharp
decline over several days indicates impending fetal
demise; consistently low levels may indicate fetal
anomalies.)
Detection of maternal disorders of pregnancy as
indicated by estriol levels that fail to show a steady
increase over several days or weeks

Pregnanetriol
Suspected adrenogenital syndrome (virilization in
women, precocious sexual development in boys)
as indicated by elevated levels
Family history of adrenogenital syndrome
Monitoring of response to cortisol therapy for
adrenogenital syndrome82
Suspected testicular tumors as indicated by
elevated levels
Suspected Stein-Leventhal syndrome as indicated
by elevated levels

Pregnanediol
Verification of ovulation in planning a pregnancy
or in determining the cause of infertility as indicated by normal values in relation to the
menstrual cycle
Diagnosis of placental dysfunction, as indicated
by either low levels or failure of levels to progressively increase, and identification of the need for
progesterone therapy to sustain the pregnancy
Detection of fetal demise as indicated by
decreased levels, although levels may remain
within normal limits if placental circulation is
adequate

Catecholamines
Hypertension of unknown etiology
Suspected pheochromocytoma as indicated by
elevated levels
Acute hypertensive episode (A random sample is
collected in such cases.)
Suspected neuroblastoma or ganglioneuroma as
indicated by elevated levels
Vanillylmandelic Acid
Hypertension of unknown etiology
Suspected pheochromocytoma as indicated by
elevated levels
Suspected neuroblastoma or ganglioneuroma as
indicated by elevated levels
Homovanillic Acid
Suspected neuroblastoma or ganglioneuroma as
indicated by elevated levels
Diagnosis of benign pheochromocytoma as indicated by normal HVA levels with elevated VMA
levels
Diagnosis of malignant pheochromocytoma as
indicated by elevated HVA and VMA levels
5-Hydroxyindoleacetic Acid
Detection of early carcinoid tumors (argentaffinomas) of the intestine as indicated by elevated
levels
Estrogens and Estrogen Fractions
Suspected tumor of the ovary, testicle, or adrenal
gland as indicated by elevated total estrogens and
fractions
Suspected ovarian failure as indicated by
decreased total estrogens and fractions

Human Chorionic Gonadotropin
Confirmation of pregnancy within 8 to 10 days
after conception, especially in women with a
history of infertility or habitual abortion or in
women who may desire a therapeutic abortion
Suspected hydatidiform mole as indicated by
elevated levels
Suspected choriocarcinoma or testicular tumor as
indicated by elevated levels
Suspected nonendocrine tumor that produces
hCG ectopically as indicated by elevated levels
Threatened abortion as indicated by decreased
levels
NURSING CARE BEFORE THE PROCEDURE

All urine studies for hormones and their metabolites
involve collecting 24-hour urine samples (see
Appendix II); exceptions are catecholamines and
hCG, which can also be analyzed in random
samples. The client should, therefore, be instructed
on how to collect the sample. The proper container
and instructions for maintaining the collection (e.g.,
refrigerated or on ice) should be provided.
Drugs that may alter test results may be withheld
during the test, although this practice should be
confirmed with the person ordering the study.
The client should be cautioned to avoid excessive
exercise and stress during the following studies:
cortisol, aldosterone, 17-OHCS, 17-KS, 17-KGS,
catecholamines, VMA, and HVA.
The client also should be instructed on the following dietary restrictions in relation to specific tests:

CHAPTER 6—Studies

(1) aldosterone—maintain a normal salt intake;
(2) VMA—maintain a “VMA diet” (see earlier
discussion) for 2 days before the test and for the
day of the test; and (3) 5-HIAA—maintain a diet
low in serotonin (see earlier discussion) for 4 days
before the test.
For gonadal and placental hormone studies, the
date of the last menstrual period should be noted.

of Urine

261

protein) as an indicator of the accuracy of the collection because the amount excreted in 24 hours
should be fairly constant. Measurement of urinary
levels of uric acid are discussed later. Amino acids
are also products of protein metabolism. As
discussed later, abnormal metabolism and congenital disorders (e.g., phenylketonuria) are associated
with excessive levels of certain amino acids.

THE PROCEDURE

URIC ACID

All urine studies for hormones and their metabolites
involve collecting 24-hour urine specimens; exceptions are catecholamines and hCG, which can also be
analyzed in random samples. For 24-hour collections, an acidifying preservative is added to the
container by the laboratory. In addition, some laboratories require that the sample be refrigerated or
placed on ice throughout the collection period.
Special diets may be required before collection of
24-hour urines for VMA and 5-HIAA (see preceding
“Nursing Care Before the Procedure” section).
Random samples for catecholamines can be
collected at any time but frequently are obtained
after a hypertensive episode. Random samples for
hCG are more reliable if collected first thing in the
morning because dilute urine may lead to falsenegative results.
All specimens should be sent promptly to the
laboratory when the collection is completed.

Uric acid is an end product of purine metabolism.
Purines are constituents of nucleic acids in the body
and appear in the urine in the absence of dietary
sources of purines. Dietary sources of purines
include organ meats, legumes, and yeasts. Uric acid
is filtered, absorbed, and secreted by the kidneys and
is a common constituent of urine.
The amount of uric acid produced in the body
and the efficiency of renal excretion affect the
amount of uric acid found in urine. Excessive
amounts of uric acid may be found in excessive
dietary intake of purines, in massive cell turnover
with degradation of nucleic acids, and in disorders
of purine metabolism. The body’s ability to filter,
reabsorb, and secrete uric acid affects the amount of
uric acid ultimately found in urine.83
Elevated urinary uric acid is commonly associated
with neoplastic disorders such as leukemia and
lymphosarcoma. It may be found also in individuals
with pernicious anemia, sickle cell anemia, and polycythemia. Disorders associated with impaired renal
tubular absorption (e.g., Fanconi’s syndrome and
Wilson’s disease) also lead to elevated uric acid levels
in urine.84
Drugs used to treat elevated serum uric acid levels
frequently work by increasing urinary excretion of
the substance. Such drugs include probenecid and
sulfinpyrazone. Allopurinol also decreases serum
uric acid levels but without necessarily leading to
excessive urinary levels.85 Note that colchicine, a
drug frequently used to treat gout, does not alter
urinary levels of uric acid. Other drugs associated
with elevated urinary uric acid include aspirin (large
doses), adrenocorticosteroids, coumarin anticoagulants, and estrogens.
Although gout is associated with elevated serum
uric acid levels (see Chapter 5), decreased amounts
of uric acid are often found in urine because of
impaired tubular excretion. Decreased amounts of
urinary uric acid also are associated with various
renal diseases for the same reason. Decreased
urinary uric acid levels are associated with lactic
acidosis and ketoacidosis because of impaired renal
excretion and also with ingestion of alcohol, aspirin
(small doses), and thiazide diuretics.

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include resuming
the client’s usual diet, medications, or activities at
completion of specimen collection.

PROTEINS AND THEIR METABOLITES
Normally, the urine contains only a scant amount of
protein. Excessive amounts of protein in the urine
are generally associated with renal disease. Thus,
part of the screening process in a UA is to test
the sample for protein. If increased amounts are
found, a quantitative 24-hour urine collection is
performed. The presence of certain types of proteins
in urine also is diagnostic of specific disease states.
The presence of Bence Jones protein in the urine, for
example, is associated with multiple myeloma.
Protein metabolites such as creatinine and uric
acid can also be measured in urine. Creatinine,
which is produced at a fairly constant rate within the
body, is a sensitive indicator of glomerular function
because factors affecting creatinine clearance are
primarily the result of alteration in renal function.
Creatinine levels can also be measured along with
24-hour measures of other substances in urine (e.g.,

262

SECTION I—Laboratory

Tests

AMINO ACIDS

Elevated amino acid levels in urine are associated
with congenital defects and disorders of amino acid
metabolism. The major inherited disorders include
phenylketonuria (PKU), tyrosyluria, and alkaptonuria. PKU occurs when the normal conversion of
phenylalanine to tyrosine is impaired, leading to the
excretion of increased keto acids such as
phenylpyruvate in the urine, which can be detected
on screening tests. If undetected and untreated, PKU
results in severe mental retardation. Blood tests for
PKU may also be performed.
Tyrosyluria occurs because of either inherited
disorders or metabolic defects. It is most frequently
seen in premature infants with underdeveloped liver
function, but it seldom results in permanent
damage. Acquired severe liver disease also leads to
tyrosyluria, as well as to the appearance of tyrosine
crystals in the urine.
Alkaptonuria represents another defect in the
phenylalanine–tyrosine conversion pathway. In this
disorder, homogentisic acid accumulates in the
urine. Alkaptonuria generally manifests in adulthood and leads to deposition of brown pigment in
the body, arthritis, liver disease, and cardiac disorders.86
URINE HYDROXYPROLINE

A special urinary test for a specific amino acid is
measurement of urine hydroxyproline, a component
of collagen in skin and bone. Foods such as meat,
poultry, fish, and foods containing gelatin falsely
elevate levels and must, therefore, be restricted for at
least 24 hours before the test. Drugs such as ascorbic
acid, vitamin D, glucocorticoids, aspirin, mithramycin, and calcitonin will also elevate levels, as will
skin disorders such as burns and psoriasis.87
INTERFERING FACTORS

Improper specimen collection and improper
specimen maintenance
Ingestion of foods and drugs that may alter test
results or failure to ingest certain foods (e.g., a
low-purine diet leads to decreased levels of
urinary uric acid; lack of protein intake may lead
to false-negative PKU test results in infants)
Skin disorders such as psoriasis and burns that
may falsely elevate urine hydroxyproline levels
INDICATIONS FOR MEASUREMENT OF
URINARY PROTEINS

Protein
Detection of various types of renal disease as indicated by elevated levels

Detection of possible complications of pregnancy
as indicated by elevated levels
Bence Jones Protein
Detection of multiple myeloma
Creatinine
Assessment of glomerular function with
decreased levels indicating impairment (see also
preceding “Reference Values” section)
Assessment of the accuracy of 24-hour urine
collections for other substances
Uric Acid
Monitoring for urinary effects of disorders that
cause hyperuricemia
Monitoring for response to therapy with uricosuric drugs
Comparison of urine levels with serum uric acid
levels to provide for an index of renal function
Amino Acid Screening Tests
Detection of inherited and metabolic disorders
such as PKU, tyrosyluria, alkaptonuria, cystinuria,
and maple syrup urine disease
Urine Hydroxyproline
Detection of disorders associated with increased
bone reabsorption (e.g., Paget’s disease, metastatic
bone tumors, and certain endocrine disorders)
Monitoring of treatment for Paget’s disease
NURSING CARE BEFORE THE PROCEDURE

The client should be instructed in the method to be
used for obtaining the sample (e.g., 24-hour urine,
2-hour urine, clean-catch midstream sample).
A medication history should be obtained.
Drugs that may alter test results may be withheld
during the test, although this practice should be
confirmed with the person ordering the study.
The client also must be instructed in any dietary
modifications needed for the test. Such dietary
modifications may be necessary in uric acid and
urine hydroxyproline tests.
THE PROCEDURE

Protein, Creatinine, and Uric Acid. A 24-hour
urine specimen is collected. For creatinine measures,
a preservative is usually added to the collection
container by the laboratory. It may be necessary also
to refrigerate the sample.
Bence Jones Protein. An early morning sample of
at least 60 mL is collected. The sample should be sent
promptly to the laboratory. It is recommended that
the sample be collected using the clean-catch
midstream technique (see Appendix II) to avoid

CHAPTER 6—Studies

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263

Reference Values
Conventional Units
Protein

SI Units

0–150 mg/24 hr

0–150 mg/day

Men

1–1.9 g/24 hr

8.8–17.6 mmol/day

Women

0.8–1.7 g/24 hr

7–15.8 mmol/day

Bence Jones protein

Negative

Uric acid

250–750 mg/24 hr

1.5–4.5 mmol/day

Negative

Men

0.4–5 mg/2 hr

3.1–38 mol/2 hr

Women

0.4–2.9 mg/2 hr

3.1–22 mol/2 hr

14–45 mg/24 hr

0.11–0.36 mmol/day

Notify physician of protein
levels 4 g/24 hr

Notify physician of protein
levels 50 nmol/day

Creatinine

Amino acids
Screening tests (e.g., for PKU,
tyrosyluria, alkaptonuria,
cystinuria, maple
syrup urine disease)
Urine hydroxyproline
2-hour sample

24-hour sample
Adults
Critical values

Note: Values are higher in children and during the third trimester of pregnancy

contaminating the sample with other proteins from
bodily secretions.
Amino Acid Screening Tests. A random urine specimen of at least 20 mL is collected. In infants, collection involves application of a urine-collecting
device. The specimen should be sent immediately to
the laboratory. The PKU (phenylpyruvic acid) test is
performed no fewer than 3 days after birth. It is
performed by pressing a Phenistix reagent strip on a
wet diaper or by dipping the strip into a sample
obtained with a urine-collecting device, waiting
30 seconds, and comparing it to a color chart. The
chart is scaled at milligram concentrations of the
substance, ranging from 0 to 100.
Urine Hydroxyproline. A 2- or 24-hour urine specimen is collected in a container to which preservative
has been added. It may also be necessary to refrigerate the sample.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include resuming

the any withheld or modified diet and medications.
Compromised renal function: Note and report
presence of or increases in proteins. Monitor I&O
and fluid and protein restrictions. Instruct in
dietary and fluid inclusions and exclusions.
Critical values: Notify physician immediately
of a protein level of greater than 4 g/24 hr.

VITAMINS AND MINERALS
The functions and serum assays of vitamins and
minerals are discussed in Chapter 5. In general,
serum assays are preferred to the more cumbersome
urine level determinations, which require 24-hour
urine collections.
VITAMINS

Fat-soluble vitamins are not readily excreted in
the urine, and therefore urinary determinations
focus on water-soluble vitamins B and C. Urinary
determinations for vitamins B1 (thiamine), B2
(riboflavin), and C may be made in suspected defi-

264

SECTION I—Laboratory

Tests

ciency states. The Schilling test for vitamin B12
absorption is discussed in Chapter 20, because it is
used to diagnose an abnormality of hematopoiesis.
MINERALS

Minerals are essential to normal body metabolism.
In urine, three commonly measured minerals
include iron (found in hemosiderin), copper, and
oxalate. Copper aids in the formation of hemoglobin
and is a component of certain enzymes necessary for
energy production.88 Elevated urinary copper levels
are associated with Wilson’s disease, an inherited
disorder of copper metabolism. Oxalate is found in
combination with calcium in certain kidney stones.
Elevated urinary oxalate levels are seen in hyperoxaluria, a disorder in which oxalate accumulates in
soft tissues, especially those of the kidney and bladder.89 Oxalate levels can also be elevated by excessive
ingestion of strawberries, tomatoes, rhubarb, or
spinach.
INTERFERING FACTORS

Improper specimen collection and maintenance
may affect test results.
Ingestion of strawberries, tomatoes, rhubarb, or
spinach may falsely elevate oxalate levels.
INDICATIONS FOR MEASUREMENT OF VITAMINS
AND MINERALS IN URINE

Detection of vitamin deficiency states
Screening for and detection of Wilson’s disease as
indicated by elevated urinary copper levels
Detection of hyperoxaluria as indicated by
elevated oxalate levels

NURSING CARE BEFORE THE PROCEDURE

The client should be instructed in the method of
obtaining the sample (i.e., usually a 24-hour urine
collection).
THE PROCEDURE

A 24-hour urine specimen is collected. Samples for
oxalate should be collected in containers that have
been protected from light and to which hydrochloric
acid has been added.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include resuming
the client’s usual diet, medications, or activities at
completion of specimen collection.

MICROBIOLOGIC EXAMINATION
OF URINE
Urine tests for culture and sensitivity (C&S) indicate
the type and number of organisms present in the
specimen (culture) and the antibiotics to which the
organisms are susceptible (sensitivity). In urine, it is
common to culture out only one organism, although
polymicrobial infections may be seen in individuals
with Foley catheters. Most organisms infecting the
urinary tract are derived from fecal flora that have
ascended the urethra. Organisms commonly found
in urine include Escherichia coli, Enterococcus,
Klebsiella, Proteus, and Pseudomonas.90
After treatment with the appropriate antibiotic, as
indicated by sensitivity tests, follow-up urine
cultures may be undertaken to determine the effectiveness of treatment.

Reference Values
Conventional Units

SI Units

Vitamins
B1 (thiamine)

100–200 g/24 hr

B2 (riboflavin)
Men

0.51 mg/24 hr

1356 nmol/day

Women

0.39 mg/24 hr

1037 nmol/day

C (ascorbic acid) 30 mg/ 24 hr
Minerals
Copper

15–60 g/24 hr

0.24–0.94 mol/day

Oxalate

40 mg/24 hr

456 mol/day

CHAPTER 6—Studies

Reference Values
Negative for pathologic organisms
Critical values: Notify physician if the culture
result is greater than 100,000 organisms/mL (SI
1,000,000 CFU/L).

of Urine

265

to detect cancer of the bladder and cytomegalic
inclusion disease.91 In these disorders, abnormal
cells are shed into the urine and can be detected
upon examination of the sample.
Reference Values
Negative for abnormal cells and inclusions

INTERFERING FACTORS

Improper specimen collection so that the sample
is contaminated with nonurinary organisms
Delay in sending the specimen to the laboratory
(Bacteria may multiply in nonrefrigerated
samples.)
INDICATIONS FOR MICROBIOLOGIC
EXAMINATION OF URINE

Suspected UTI
Identification of antibiotics to which the cultured
organism is sensitive
Monitoring for response to treatment for UTIs

INTERFERING FACTORS

Improper specimen collection such that the
sample is contaminated with extraneous cells
Delay in sending the sample to the laboratory
(Cells may begin to disintegrate.)
INDICATIONS FOR CYTOLOGIC
EXAMINATION OF URINE

Suspected cancer of the bladder or other urinary
tract structure, especially in individuals exposed
to environmental carcinogens
Suspected infection with cytomegalovirus

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of either a clean-catch
midstream urine specimen, a catheterized specimen,
or a suprapubic aspiration (see Appendix II).

NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of a clean-catch midstream
urine specimen, a catheterized specimen, or a suprapubic aspiration (see Appendix II).

THE PROCEDURE

A sample of at least 5 to 10 mL is obtained either by
clean-catch technique, catheterization, or suprapubic aspiration. The sample is placed in a sterile
container and is transported to the laboratory
immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include assessing
the suprapubic site for inflammation if the specimen
was obtained by aspiration. Cover the area with a
sterile dressing.

THE PROCEDURE

A sample of at least 180 mL in adults and 10 mL
in children is obtained either by the clean-catch
technique, catheterization, or suprapubic aspiration.
Depending on the laboratory, a special container
or preservative, or both, may be needed. The
sample must be transported to the laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Critical values: Notify physician immediately if
the culture result is greater than 100,000 organisms/mL (SI 1,000,000 CFU/L).

Care and assessment after the test include assessing
the suprapubic site for inflammation if the specimen
was obtained by aspiration.
Cover the area with a sterile dressing.

CYTOLOGIC EXAMINATION
OF URINE

DRUG SCREENING TESTS
OF URINE

Cytology is the study of the origin, structure, function, and pathology of cells. In clinical practice, cytologic examinations are generally performed to detect
cell changes caused by malignancies or inflammatory conditions.
Cytologic examination of urine is performed
when cancer or inflammatory disorders of the
urinary tract are suspected. It is especially indicated

Toxicological analysis of urine is performed to identify drugs that have been used and abused. Urine is
preferred for drug screening because most drugs are
detectable in urine but not in blood. The exception
is testing for alcohol concentration. The screening
tests are performed in groups according to the pharmacological classification of the drugs. Commonly
used substances that involve a risk for psychological,

266

SECTION I—Laboratory

Tests

physical, or both psychological and physical dependence and are tested are the following:
Sedatives: benzodiazepines, methaqualone
Depressants: alcohol, barbiturates, opiates
(codeine, morphine, methadone)
Stimulants: amphetamines, cocaine, “crack,”
methylphenidate
Hallucinogens:
cannabinoids
(marijuana,
hashish), phencyclidine (PCP), lysergic acid
diethylamide (LSD), mescaline92
Drug abuse includes the recreational use of drugs
(illicit use); unwarranted use of drugs to relieve
problems or symptoms, leading to dependence and
later continued use; and therapeutic use to prevent
the consequences of withdrawal. These substances
act on the CNS to reduce anxiety and tension,
produce euphoria and other pleasurable mood
changes, increase mental and physical ability, and
alter sensory perceptions and change behaviors.93
Detection of levels varies with the time of the last
dose of a specific drug and can range from hours to
days to weeks.
Anabolic steroids (synthetic derivatives of testosterone) are used to enhance athletic performance
primarily in power-related sports and, in some
instances, to improve appearance. Its use (known as
“sports doping”) results in a change in body bulk,
strength, and energy. Psychological effects include
mood swings, aggressiveness, and irrational behavior. Physical effects include liver dysfunction and
cardiovascular dysfunction that result from hypertension and increased low-density lipoproteins.
Anabolic steroid metabolites can be detected in the
urine for up to 6 months after drug use.94
Reference Values
Negative for drugs in group tested
INTERFERING FACTORS

High or low pH of urine (alkaline or acid levels)
Blood or other abnormal constituents in the urine
Urine that has a low specific gravity, causing dilution
INDICATIONS FOR DRUG SCREENING
TESTS OF URINE

Determination of abuse of drugs before or during
employment in which public welfare is at stake
Identification of use of drugs to enhance athletic
ability and success
Detection and identification of specific drugs
when use and abuse is suspected so as to differentiate it from other causes of a set of signs and
symptoms

Confirmation of a diagnosis of drug overdose
after death
Detection of drug use before prescribing a
medication or treatment regimen
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any test involving the collection of a random urine specimen (see
Appendix II).
If drug abuse is suspected, the collection and
delivery of the urine sample should be witnessed
by a legally responsible person and labeled with a
code instead of a name and other personal information.
The client should be informed of the procedure to
collect and test the specimen, the reporting protocol, and possible implications of the results.
THE PROCEDURE

A random sample of 50 to 100 mL of urine is
collected in a clean container and covered with a lid
and labeled with a code while a trained witness
observes to ensure that the specimen has been
obtained from the correct client. The specimen
container is placed in a plastic bag and sealed to
ensure that any tampering with the package will
be revealed. The signatures of the individual
who collects the specimen and anyone who handles
it in any way are required on a document. The
specimen is examined by enzyme immunoassay
or fluorescence polarization immunoassay procedures. Confirmation tests are performed to ensure
that false-positive results are resolved. Because
of the legal implications, documented testing
procedures for a positive, negative, or unconfirmed
result with evidence to support the result should
accompany the test report. After the complete
testing of the specimen, the sample is resealed in the
labeled bag and stored for 30 days or as long as
needed.95
NURSING CARE AFTER THE PROCEDURE

No specific care is needed after these tests. Inform
the client of the possible economic, psychological,
and legal implications of a confirmed positive test.
Abnormal results: Note and report effect of
results on client’s psychological and physical
health, economic status (work, sports), and legal
status (illicit drug use). Ensure that correct testing
and confirmation were performed and reported.
Advise client to consider drug abuse counseling or
educational programs, or both, provided by
school officials, coaches, physicians, and other
health-care professionals.

CHAPTER 6—Studies

REFERENCES
1. Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis,
Philadelphia, 2001, p 25.
2. Ibid, pp 25–26.
3. Porth, CM: Pathophysiology: Concepts of Altered Health States, ed
5. JB Lippincott, Philadelphia, 1998, p 580.
4. Strasinger, op cit, p 25.
5. Ibid, p 27.
6. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, p 699.
7. Ibid, p 699.
8. Strasinger, op cit, p 35.
9. Schweitzer, GB, and Schumann, GB: Examination of urine. In
Henry, JB: Clinical Diagnosis and Management by Laboratory
Methods, ed 18. WB Saunders, Philadelphia, 1991, p 393.
10. Strasinger, op cit, p 35.
11. Ibid, p 36.
12. Schweitzer and Schumann, op cit, p 394.
13. Ibid, p 395.
14. Strasinger, op cit, p 41.
15. Ibid, p 37.
16. Ibid, p 38.
17. Schweitzer and Schumann, op cit, p 400.
18. Strasinger, op cit, p 46.
19. Schweitzer and Schumann, op cit, p 399.
20. Ibid, p 399.
21. Ibid, p 400.
22. Ibid, p 402.
23. Ibid, p 401.
24. Strasinger, op cit, p 48.
25. Schweitzer and Schumann, op cit, p 401.
26. Strasinger, op cit, p 47.
27. Porth, op cit, p 573.
28. Schweitzer and Schumann, op cit, p 405.
29. Ibid, pp 407–408.
30. Strasinger, op cit, p 53.
31. Ibid, p 54.
32. Schweitzer and Schumann, op cit, p 409.
33. Ibid, p 410.
34. Ibid, p 410.
35. Strasinger, op cit, p 55.
36. Schweitzer and Schumann, op cit, p 410.
37. Ibid, p 410.
38. Strasinger, op cit, p 56.
39. Ibid, p 58.
40. Schweitzer and Schumann, op cit, p 415.
41. Ibid, p 415.
42. Strasinger, op cit, pp 60–61.
43. Ibid, p 61.
44. Schweitzer and Schumann, op cit, p 416.
45. Strasinger, op cit, p 62.
46. Schweitzer and Schumann, op cit, p 417.

47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
78.
79.
80.
81.
82.
83.
84.
85.
86.
87.
88.
89.
90.
91.
92.
93.
94.
95.

of Urine

267

Strasinger, op cit, p 62.
Ibid, pp 68.
Schweitzer and Schumann, op cit, p 421.
Strasinger, op cit, p 77.
Schweitzer and Schumann, op cit, p 421.
Strasinger, op cit, p 79.
Schweitzer and Schumann, op cit, p 423.
Ibid, p 424.
Ibid, p 424.
Ibid, p 424.
Strasinger, op cit, p 87.
Schweitzer and Schumann, op cit, p 425.
Strasinger, op cit, pp 95–99.
Ibid, p 103.
Sacher and McPherson, op cit, pp 711–712.
Strasinger, op cit, p 15.
Sacher and McPherson, op cit, p 711.
Ibid, p 712.
Ibid, p 713.
Strasinger, op cit, p 20.
Sacher and McPherson, op cit, p 714.
Strasinger, op cit, p 18.
Sacher and McPherson, op cit, p 715.
Strasinger, op cit, p 37.
Corbett, JV: Laboratory Tests and Diagnostic Procedures with
Nursing Diagnoses, ed 3. Appleton & Lange, Norwalk, Conn, 1992,
p. 127.
Sacher and McPherson, op cit, p 721.
Schweitzer and Schumann, op cit, p 433.
Ibid, p 459.
Strasinger, op cit, pp 36–37.
Strasinger, op cit, pp 142–143.
Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 374.
Ibid, pp 376–377.
Sacher and McPherson, op cit, p 564.
Ibid, p 581.
Ibid, pp 403–404.
Ibid, pp 394–396.
Ibid, p 330.
Nurse’s Reference Library, op cit, p 423.
Sacher and McPherson, op cit, p 331.
Strasinger, op cit, pp 138–139.
Nurse’s Reference Library, op cit, pp 418–419.
Ibid, p 451.
Ibid, pp 464–465.
Sacher and McPherson, op cit, p 499.
Fischbach, FT: A Manual of Laboratory Diagnostics Tests, ed 4. JB
Lippincott, Philadelphia, 1992, pp 709–710.
Sacher and McPherson, op cit, pp 686–688.
Berkow, R (ed): The Merck Manual, ed 16. Merck Sharp and
Dohme Research Laboratory, Rahway, NJ, 1992, p 1549.
Ibid, p 2277.
Fischbach, op cit, p 186.

CHAPTER

Sputum Analysis
TESTS COVERED
Gram Stain and Other Stains, 269
Culture and Sensitivity, 271

Acid-Fast Bacillus Smear and Culture, 272
Cytologic Examination, 272

OVERVIEW OF SPUTUM PRODUCTION AND ANALYSIS

Sputum is the material
secreted by the tracheobronchial tree and, by definition, brought up by coughing. The submucosal glands and secretory cells of the tracheobronchial mucosa normally secrete up to 100 mL
of mucus per day as part of bronchopulmonary cleansing. The secretions form a thin layer over
the ciliated epithelial cells and travel upward toward the oropharynx, carrying inhaled particles
away from the bronchioles. From the oropharynx the secretions are swallowed; therefore, the
healthy person does not produce sputum.
In addition to its mechanical cleansing action, mucus attacks inhaled bacteria directly. This
antibacterial effect is primarily the result of antibodies, which are predominantly IgA, but
also of lysozymes and slightly acid pH. Normally, the contents of the lower respiratory tract are
sterile.
Environmental factors, drugs, and respiratory tract disease alter tracheobronchial secretions
and may lead to sputum production. Tobacco smoke, cold air, alcohol, and sedatives depress
ciliary action and may cause stasis of secretions. Respiratory infections cause an increase in
secretions and may lead to a more acidic pH and changes in the chemical composition. A pH
below 6.5 inhibits ciliary action, as does increased sputum viscosity. Leukocytes present in
respiratory secretions also rise during infection, and membrane permeability increases because
of the normal inflammatory response. Thus, antibiotics and other elements normally found in
the blood may be present in the sputum. The quantity of sputum produced in pathological
states is roughly parallel to the severity of the problem. Specific characteristics and constituents
of sputum help to determine the nature of the disorder.1
The most common laboratory tests performed on sputum are (1) Gram stain and other
staining tests, (2) culture and sensitivity, (3) examination for acid-fast bacilli (AFB), and (4)
cytologic examination. The gross appearance of the specimen should, however, be observed
and documented before sending the sample to the laboratory. Respiratory secretions are
normally clear, colorless, odorless, and slightly watery.
Abnormal sputum can be described as mucoid (consisting of mucus), mucopurulent
(consisting of mucus and pus), and purulent (consisting of pus). Expectoration of mucoid
sputum is seen in chronic bronchitis and asthma. A change from mucoid to mucopurulent
sputum indicates infection superimposed on the chronic inflammatory condition.2 Purulent
sputum may indicate acute bacterial pneumonia, bronchiectasis, or rupture of a pulmonary
abscess. Foul-smelling sputum is also associated with bronchiectasis and lung abscess, as well as
with cystic fibrosis. Viscous (tenacious) secretions are seen in clients with cystic fibrosis,
Klebsiella pneumonia, and dehydration.3
268

CHAPTER 7—Sputum

Analysis

269

Purulent sputum is yellow to green. Gray sputum may indicate inhaled dust; grayish-black
sputum is seen after smoke inhalation. Frothy pink or rusty-colored sputum is associated with
congestive heart failure (CHF). It is abnormal to expectorate blood (hemoptysis), whether the
quantity involves only a few scant streaks or a life-threatening hemorrhage. In addition to being
associated with CHF, rusty-colored sputum may be seen also in pneumococcal pneumonia,
whereas bright streaks of blood are associated with Klebsiella pneumonia. Dark blood in small
amounts is associated with tuberculosis, tumors, and trauma caused by instrumentation.
Bright blood in moderate to large amounts is associated with cavitary tuberculosis, broncholithiasis, and pulmonary thrombosis.

SPUTUM TESTS
GRAM STAIN AND OTHER STAINS
Gram staining is one of the oldest and most useful
microbiologic staining techniques. It involves
smearing a small amount of sputum on a slide and
then exposing it to gentian or crystal violet, iodine,
alcohol, and safranine, a red dye. This technique
allows for morphological examination of the cells
contained in the specimen and differentiates any
bacteria present into either gram-positive organisms, which retain the iodine stain, or gram-negative
organisms, which do not retain the iodine stain but
can be counterstained with safranine.
Gram staining can be used to differentiate true
sputum from saliva and upper respiratory tract
secretions. True sputum contains polymorphonuclear leukocytes and alveolar macrophages. It should
also contain a few squamous epithelial cells.
Excessive squamous cells or the absence of polymorphonuclear leukocytes usually indicates that the
specimen is not true sputum.
Another stain used in sputum examinations is
polychromase chain reaction, used when pulmonary
alveolar proteinosis or Pneumocystis carinii pneumonia is suspected. A characteristic of pulmonary
alveolar proteinosis is compacted protein, which can
be found either inside mononuclear cells, free in
round or laminated clumps, or in aggregates with
cleftlike spaces. The round and laminated clumps
may resemble the cysts of P. carinii.
Reference Values
Normal sputum contains polymorphonuclear
leukocytes, alveolar macrophages, and a few
squamous epithelial cells.

INTERFERING FACTORS

Improper specimen collection
Delay in sending specimen to the laboratory

INDICATIONS FOR GRAM STAIN AND OTHER
STAIN TESTS

Gram Stain
Differentiation of sputum from upper respiratory
tract secretions, the latter being indicated by
excessive squamous cells or the absence of polymorphonuclear leukocytes
Determination of types of leukocytes present in
sputum (e.g., neutrophils indicating infection and
eosinophils seen in asthma)
Differentiation of gram-positive from gram-negative bacteria in respiratory infections
Identification of Curschmann’s spirals, which are
associated with asthma, acute bronchitis, bronchopneumonia, and lung cancer4
Wright’s Stain
Confirmation of the types of leukocytes present in
sputum
Polychromase Chain Reaction
Identification of compacted proteins associated
with pulmonary alveolar proteinosis
Identification of cysts associated with P. carinii
infections
Confirmation of the presence of cysts associated
with P. carinii infections
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That results are most reliable if the specimen is
obtained in the morning upon arising, after secretions have accumulated overnight
That a sample of secretions from deep in the
respiratory tract, not saliva or postnasal drainage,
is needed
The methods by which the specimen will be
obtained (i.e., by coughing or by tracheal suctioning)
That increasing fluid intake before retiring for the
night aids in liquefying secretions and may make
them easier to expectorate

270

SECTION I—Laboratory

Tests

That humidifying inspired air also helps to liquefy
secretions
That, if feasible, the client should brush the teeth
or rinse the mouth before obtaining the specimen
to avoid excessive contamination of the specimen
with organisms normally found in the mouth
Proper handling of the container and specimen, if
the client is to obtain the specimen independently
The number of samples to be obtained, because it
may be necessary to analyze more than one
sample for accurate diagnosis
Prepare for the procedure:
Assist in providing extra fluids, unless contraindicated, and proper humidification.
Assist with mouth care as needed.
Provide sputum collection container(s).
If the specimen is to be obtained by tracheal
suctioning, it is recommended that oxygen be
administered for 20 to 30 minutes before the
procedure.
Hyperventilation with 100% O2 should be
performed before and after suctioning.
THE PROCEDURE

The procedure varies with the method for obtaining
the sputum specimen. The nurse should wear gloves,
face mask, and possibly glasses or goggles when
obtaining the sputum sample.
Expectorated Specimen. The client should sit
upright, with assistance and support (e.g., with an
overbed table) as needed. The client should then
take two or three deep breaths and cough deeply.
Any sputum raised should be expectorated directly
into a sterile container. The client should not touch
the lip or the inside of the container with the hands
or mouth. A 10- to 15-mL specimen is adequate.
If the client is unable to produce the desired
amount of sputum, several strategies may be
attempted. One approach is to have the client drink
two glasses of water and then assume the positions
for postural drainage of the upper and middle lung
segments. Support for effective coughing may be
provided by placing the hands or a pillow over the
diaphragmatic area and applying slight pressure.
Another approach is to place a vaporizer or other
humidifying device at the bedside. After sufficient
exposure to adequate humidification, postural
drainage of the upper and middle lung segments
may be repeated before attempting to obtain the
specimen.
It may also be helpful to obtain an order for an
expectorant and administer it along with additional
water approximately 2 hours before attempting to
obtain the specimen. In addition, chest percussion

and postural drainage of all lung segments may be
used. If the client still is unable to raise sputum, the
use of an ultrasonic nebulizer (“induced sputum”)
may be necessary. This is usually undertaken by a
respiratory therapist.
Tracheal Suctioning. Suction equipment, a suction
kit, and a Lukens tube or in-line trap are obtained.
The client is positioned with head elevated as high as
tolerated. Sterile gloves are applied, with the dominant hand maintained as “sterile” and the nondominant hand as “clean.” The suction catheter is
attached with the “sterile hand” to the rubber tubing
of the Lukens tube or in-line trap. The suction
tubing is then attached to the male adapter of the
trap with the “clean” hand. The suction catheter is
lubricated with sterile saline.
Nonintubated clients should be instructed, if
feasible, to protrude the tongue and take a deep
breath as the suction catheter is passed through the
nostril. When the catheter enters the trachea, a reflex
cough is stimulated; the catheter is immediately
advanced into the trachea, and suction is applied.
Suction should be maintained for approximately
10 seconds and never for more than 15 seconds. The
catheter is then withdrawn without applying
suction. The suction catheter and suction tubing are
separated from the trap, and the rubber tubing is
placed over the male adapter to seal the unit. The
specimen is labeled and sent to the laboratory
immediately.
For clients who are intubated or have a
tracheostomy, the aforementioned procedure is
followed, except that the suction catheter is passed
through the existing endotracheal or tracheostomy
tube rather than through the nostril. The client
should be hyperoxygenated before and after the
procedure in accordance with usual protocols for
suctioning such clients.
NURSING CARE AFTER THE PROCEDURE

For specimens obtained by expectoration or nasotracheal suctioning, care and assessment after the
procedure include mouth care offered or provided
after the specimen has been obtained.
Provide a cool beverage to aid in relieving throat
irritation caused by coughing and suctioning.
Assess the client’s color and respiratory rate, and
administer supplemental oxygen as necessary.
For specimens obtained by endotracheal tube or
tracheostomy, hyperoxygenate the client after the
procedure according to usual protocols.
Additional suctioning may be necessary to clear
secretions raised during suctioning to obtain the
specimen.

CHAPTER 7—Sputum

The characteristics (e.g., color, consistency,
volume) of the sample should be noted and documented.
Infection or hypoxemia: Note and report tachypnea, dyspnea, diminished breath sounds, change
in skin color (cyanosis), and elevated temperature. Administer oxygen and have emergency
intubation equipment on hand.
Transmission of respiratory pathogens: Place on
respiratory precautions. Use mask when in
contact with client. Dispose of used articles
according to standard precautions and transmission-based isolation procedures.
Critical values: Notify physician immediately if
test result is positive.

CULTURE AND SENSITIVITY
Sputum tests for culture and sensitivity (C&S) indicate the type and number of organisms in the specimen (culture) and the antibiotics to which the
organisms are susceptible (sensitivity). Although
examination of the organisms found in sputum by
microscopy or stain may lend support in the diagnosis of suspected infectious disorders, growth of a
pathogen in culture is more definitively diagnostic.
The pathogenic organisms most often cultured
from the sputum of individuals with bacterial pneumonia are Streptococcus pneumoniae, Haemophilus
influenzae, Staphylococcus, and gram-negative
bacilli. Other pathogens that may be identified in
sputum cultures include Klebsiella pneumoniae,
Mycobacterium tuberculosis, fungi such as Candida
and Aspergillus, Corynebacterium diphtheriae, and
Bordetella pertussis. In contrast, other organisms that
can cause pneumonia, such as mycoplasmas, respiratory viruses, and rickettsiae, are not detected on
routine culture.5 Sputum collected by expectoration
or suctioning with catheters and by bronchoscopy
cannot be cultured for anaerobic organisms. Instead,
transtracheal aspiration or lung biopsy must be
used.6
Interpretation of the results of sputum cultures
requires knowledge of the client’s symptomatology
and the nature of the pathogen cultured. Pathogens
may be identified in the sputum of individuals who
do not have pneumonia or whose pneumonia is
actually caused by an organism not identified on
culture. Similarly, a person may be diagnosed as
having pneumonia on the basis of sputum cultures,
when the infection is caused by an obstruction by
tumors or foreign bodies, pulmonary infarction, or
pulmonary hemorrhage. If Candida or Aspergillus is
found on culture, the client must be further evalu-

Analysis

271

ated, because these environmental contaminants
may be the cause of serious pulmonary disease.7 In
legionnaires’ disease, sputum cultures and Gram
staining are negative, despite clinical signs of severe
pneumonia. When this disease is suspected, confirmation must be obtained through immunologic
blood tests (see Chapter 3).8
Rapidity of results from sputum cultures varies
according to the rate of growth of the organisms.
Routine cultures of M. tuberculosis, for example,
may take weeks to become positive. To provide more
rapid and reliable diagnostic information, some
laboratories use immunologic methods such as
counterimmunoelectrophoresis (CIEP) to identify
microbial pathogens. In CIEP, antibodies specific
to the suspected organisms are used, and rapid
confirmation of significant tissue involvement is
possible.9
Reference Values
Normal respiratory flora include Moraxella
catarrhalis, C. albicans, diphtheroids, -hemolytic streptococci, and some staphylococci.
INTERFERING FACTORS

Improper specimen collection
Delay in sending specimen to the laboratory
C&S should be performed before antimicrobial
therapy to evaluate effectiveness of therapy.
INDICATIONS FOR CULTURE AND SENSITIVITY
TEST

Support for diagnosing the cause of respiratory
infection as indicated by the presence or absence
(e.g., viral infections, legionnaires’ disease) of
organisms in culture
Confirmatory diagnosis of tuberculosis (see also
AFB smear and culture)
Monitoring for response to treatment for respiratory infections, especially tuberculosis
Identification of antibiotics to which the cultured
organism is sensitive
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of sputum or lower respiratory secretions (see section under “Gram Stain and
Other Stains”).
THE PROCEDURE

The procedures for obtaining the specimen are the
same as those described in the “Gram Stain and
Other Stains” section.

272

SECTION I—Laboratory

Tests

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving collection of sputum
or lower respiratory secretions.
Depending on the nature of the suspected or
confirmed infection, respiratory isolation or
drainage and secretion precautions may be used,
although these infection-control protocols may
have been already implemented before obtaining
sputum cultures.
Abnormal test results, complications, and
precautions: Respond the same as for stains (see
earlier section). The client should be informed
that culture results for the more common pathogenic microorganisms can be obtained in 24 to 48
hours and that sensitivity results can cause a
change in antimicrobial therapy.

ACID-FAST BACILLUS SMEAR
AND CULTURE
The acid-fast staining method is used primarily to
identify tubercle bacilli (M. tuberculosis). Acid-fast
bacilli have a cell wall that resists decolorization by
acid treatment10; that is, they retain the stain applied
to the specimen, a small portion of which is smeared
on a slide, even after treatment with an acid-alcohol
solution.
Because the tubercle bacillus is slow growing and
culture results may take weeks, an acid-fast bacillus
(AFB) smear aids in early detection of the organism
and timely initiation of antituberculosis therapy. In
addition to organisms of the Mycobacterium genus,
Nocardia spp. and Actinomyces spp. can also be identified by acid-fast techniques.
AFB cultures are used to confirm both positive
and negative results of AFB smears. By specifying
that AFB is the organism to be detected on culture,
the laboratory is alerted to the fact that several weeks
may be needed for conclusive results. As noted,
immunologic methods may also be used in diagnosing tuberculosis by sputum analysis.
Reference Values
Negative for AFB

Monitoring for response to treatment for
pulmonary tuberculosis
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of sputum or lower respiratory secretions (see section under “Gram Stain and
Other Stains”).
The client should be informed that it may be
several weeks before culture results are available.
THE PROCEDURE

The procedures for obtaining the specimen are the
same as those described in the section under “Gram
Stain and Other Stains”).
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of
sputum or lower respiratory secretions.
If tuberculosis is suspected, the client may be
placed on AFB or respiratory isolation, pending
AFB smear results.

CYTOLOGIC EXAMINATION
Cytology is the study of the origin, structure, function, and pathology of cells. In clinical practice, cytologic examinations are generally performed to detect
cell changes resulting from malignancies or inflammatory conditions. Lipid droplets contained in
macrophages may be found on cytologic examination and may indicate lipoid or aspiration pneumonia.11
Sputum specimens for cytologic examination
may be collected by expectoration alone, during
bronchoscopy, or by expectoration after bronchoscopy. The method of reporting results of cytologic examinations varies according to the
laboratory performing the test. Terms used to report
results include negative (no abnormal cells), inflammatory, benign atypical, suspect for malignancy, and
positive for malignancy.
Reference Values
Negative for abnormal cells, Curschmann’s
spirals, fungi, ova, and parasites

INTERFERING FACTORS

Improper specimen collection
Delay in sending specimen to the laboratory
INDICATIONS FOR ACID-FAST BACILLUS SMEAR
AND CULTURE

Suspected pulmonary tuberculosis

INTERFERING FACTORS

Improper specimen collection
Delay in sending specimen to the laboratory
INDICATIONS FOR CYTOLOGIC EXAMINATION

Suspected lung cancer

CHAPTER 7—Sputum

History of cigarette smoking, which may lead to
metaplastic (nonmalignant) cellular changes
History of acute or chronic inflammatory or
infectious lung disorders, which may lead to
benign atypical or metaplastic cellular changes
Known or suspected viral disease involving the
lung
Known or suspected fungal or parasitic infection
involving the lung
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of sputum or lower respiratory secretions (see section under “Gram Stain and
Other Stains”).
THE PROCEDURE

The procedures for obtaining the specimen are the
same as those described in the “Gram Stain and
Other Stains” section. It is common practice to
collect three sputum specimens for cytologic examination, usually on three separate mornings. After
bronchoscopy, however, serial specimens may be
obtained from sputum expectorated within 12 to 24
hours of the procedure. Specimens are collected in
either sterile containers or sterile containers to

Analysis

273

which 50 percent alcohol has been added, depending
on specific laboratory procedures.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of
sputum or lower respiratory secretions.
Abnormal test results, complications, and
precautions: The client should be offered additional support if the diagnostic findings indicate a
premalignant or malignant condition and if
further diagnostic procedures or chemotherapy/
radiation therapy is advised.
REFERENCES
1. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 10. FA Davis, Philadelphia,
1991, p 747.
2. Ibid, p 748.
3. Ibid, p 749.
4. Ibid, p 749.
5. Ibid, p 749.
6. Ibid, p 453.
7. Ibid, p 749.
8. Ibid, p 456.
9. Ibid, pp 460–461.
10. Ibid, pp 460-461.
11. Ibid, p 749.

CHAPTER

Cerebrospinal
Fluid Analysis
TESTS COVERED
Routine Cerebrospinal Fluid Analysis, 275
Microbiologic Examination of
Cerebrospinal Fluid, 279

Cytologic Examination of Cerebrospinal
Fluid, 281
Serologic Tests for Neurosyphilis, 281

OVERVIEW OF CEREBROSPINAL FLUID FORMATION AND ANALYSIS
Cerebrospinal fluid (CSF) is secreted into the ventricles of the brain by specialized capillaries
called choroid plexuses. Most of the CSF arises in the lateral ventricles, although additional
amounts are secreted in the third and fourth ventricles. CSF formed in the ventricles circulates
into the central canal of the spinal cord and also enters the subarachnoid space through an
opening in the wall of the fourth ventricle near the cerebellum, after which it circulates around
the brain and spinal cord. Although 500 to 800 mL of CSF are formed daily, only 125 to 140 mL
are normally present. Thus, almost all of the CSF formed is reabsorbed via arachnoid granulations, which project from the subarachnoid space into the venous sinuses, and is subsequently
returned to the venous circulation. The functions of CSF include cushioning the brain against
shocks and blows, maintaining a stable concentration of ions in the central nervous system
(CNS), and providing for removal of wastes.1
CSF is produced by the processes of filtration, diffusion, osmosis, and active transport.
Initially, sodium is actively transported into the CSF; then water follows passively by osmosis.
Facilitated diffusion allows glucose to move between the blood and CSF. Although similar in
composition to plasma, CSF generally contains more sodium and chloride and less potassium,
calcium, and glucose. Most constituents of CSF, however, parallel those found in plasma and
are found in amounts equal to or slightly less than those in the blood.2,3
In addition to entering CSF via the choroid plexuses, substances may pass into CSF from the
blood through capillaries in the parenchyma and meninges of the brain and spinal cord.
“Barriers” exist between the blood and the CSF and between the brain and the CSF; that is,
substances do not pass as readily into the CSF as they would pass into extracellular fluid
through other capillary beds. Water, carbon dioxide, oxygen, glucose, small molecules, lipidsoluble substances, nonionized substances, and some drugs (e.g., erythromycin and sulfadiazine) pass rapidly into CSF, whereas large molecules, ionized substances, various toxins, and
certain other drugs (e.g., chlortetracyclines and penicillins) do not pass readily into CSF.4
Under pathological conditions, elements normally held back by the blood–brain barrier may
enter CSF. Red cells and white cells can enter the CSF either from rupture of vessels or from
meningeal reaction to irritation. Unconjugated (prehepatic) bilirubin may be found after
intracranial hemorrhage, whereas conjugated bilirubin may be found if the circulating plasma
274

CHAPTER 8—Cerebrospinal

Fluid Analysis

275

contains large amounts. Fibrinogen, which is normally absent from CSF, may be found along
with albumin and globulins when inflammatory disorders cause increased permeability of the
blood–brain barrier. Urea, lactic acid, and glutamine levels in CSF will rise if plasma levels of
these or related substances are elevated. Bacteria and fungi found in CSF indicate infection with
these organisms.5
As a general rule, routine CSF analysis includes a cell count and differential as well as determinations of protein and glucose levels. In addition, CSF may be analyzed for electrolytes, lactic
acid, urea, glutamine, and enzymes. Microbiologic studies of CSF include culture and sensitivity (C&S), Gram stain and other stains, acid-fast bacillus (AFB) smear and culture, and the
Limulus assay for gram-negative bacteria. Cytologic examination for malignant cells, as well as
serologic tests for syphilis, may be performed on CSF.
The gross appearance, opening pressure, and closing pressure should be noted during the
procedure and documented. The pH of the sample may also be noted. CSF is normally clear,
colorless, and of the consistency of water. Turbidity indicates the presence of a significant
number of leukocytes (i.e., greater than 200 to 500 white cells per cubic millimeter). Yellowish
discoloration of CSF (xanthochromia) usually indicates previous bleeding but may also be seen
when CSF protein levels are greatly elevated. Fresh blood in the specimen may be due to traumatic spinal tap, although clearing should be noted as the second and third tubes are withdrawn
in such a case. Bleeding from a traumatic tap adds approximately one to two white cells and 1
mg/dL of protein for every 1000 red cells per cubic millimeter contained in the sample. If blood
does not clear as subsequent samples are obtained, bleeding due to subarachnoid hemorrhage
is usually indicated. Brown CSF generally indicates a chronic subdural hematoma with CSF
stained from methemalbumin.6
Because fibrinogen is normally absent from CSF, the sample should not clot. Clotting may
occur, however, when the protein content of the sample is elevated. In conditions involving
spinal subarachnoid block, CSF may be yellow and have a tendency toward rapid spontaneous
clotting. The pH of CSF is normally slightly lower than that of blood, with a range of 7.32 to
7.35 when arterial blood pH is within normal limits.7
CSF specimens must be transported to the laboratory immediately. Within 1 hour of collection, any red cells contained in the sample begin to lyse and may cause spurious coloration of
the specimen. Neutrophils and malignant cells may also disintegrate in a short time. Bacteria
and other cells will continue to metabolize glucose, such that delays in analysis may alter chemical values.8
The opening CSF pressure (OP) is measured after the spinal needle is determined to be in the
subarachnoid space. CSF pressure may be elevated if clients are anxious and hold their breath
or tense their muscles. It may also be elevated if there is venous compression such as may occur
if the client’s knees are flexed too firmly against the abdomen. Significant elevations in CSF
pressure may occur with intracranial tumors and with purulent or tuberculous meningitis. Less
marked increases (i.e., 250 to 500 mm of water) are associated with low-grade inflammatory
processes, encephalitis, or neurosyphilis. Decreases in CSF pressure are rare but may occur with
dehydration, high obstruction to CSF flow, or previous aspiration of spinal fluid.9
The closing pressure (CP) is recorded before removal of the spinal needle from the subarachnoid space. Normally, CSF pressure decreases 5 to 10 mm of water for every milliliter of CSF
withdrawn. The expected decrease in CSF pressure does not occur in disorders in which the
total quantity of CSF is increased (e.g., hydrocephalus). In contrast, a large drop in pressure
indicates a small CSF pool and is seen in tumors or spinal block.10

CEREBROSPINAL FLUID TESTS
ROUTINE CEREBROSPINAL
FLUID ANALYSIS
Routine CSF analysis includes a cell count and
differential, as well as determinations of protein

and glucose levels. CSF may also be analyzed for
electrolytes, lactic acid, urea, glutamine, and
enzymes.
CELL COUNT AND DIFFERENTIAL

Normal spinal fluid is free of cells. Note that crypto-

276

SECTION I—Laboratory

Tests

coccal organisms in the sample may be mistaken for
small lymphocytes.
PROTEINS

CSF normally contains very little protein because
most proteins cannot cross the blood–brain barrier.
In addition to determining the amount of protein
present in CSF, levels of certain types of protein may
also be measured. Albumin, for example, is a relatively small molecule and may pass more easily into
CSF. For this reason, the albumin-to-globulin (A-G)
ratio is normally higher in CSF than in serum.
Protein electrophoresis may also be performed on
CSF samples.
The protein concentration in CSF may rise as a
result of increased permeability of the blood–brain
barrier because of inflammation and infection. CSF
protein levels may also be elevated in clients with
diabetes mellitus and cardiovascular disease because
of increased permeability of the blood–brain
barrier.11
GLUCOSE

The glucose concentration of CSF is altered by the
presence of microorganisms. Because all types of
organisms consume glucose, levels will be decreased
if the CSF contains bacteria, fungi, protozoa, or
tubercle bacilli. However, this decrease is not as
pronounced or may not be seen at all in viral meningitis.
Bacterial and other cells present in CSF continue
to metabolize glucose even after the sample has been
collected. Thus, spuriously low glucose levels may be
found in CSF if analysis is delayed.
OTHER SUBSTANCES

Other substances for which CSF may be analyzed
include electrolytes, lactic acid, urea, glutamine, and
enzymes. The electrolyte levels found in CSF are
similar to those of plasma, with the exceptions of
sodium and chloride, which are higher, and potassium and calcium, which are lower. The significance
of electrolyte levels in CSF is questionable. Some
writers, for example, indicate that chlorides are
decreased in tuberculosis and bacterial meningitis.12,13 Others state that chloride levels provide no
specific diagnostic information.14 The calcium
found in CSF is that fraction not bound by protein
and is about half that of serum levels. Calcium levels
rise with CSF protein levels; it is more important to
determine the protein level in such cases, however,
than to measure calcium.15
Lactic acid in CSF reflects local glycolytic activity
and adds to diagnostic information when results of
other analyses are inconclusive. Severe systemic
lactic acidosis causes CSF lactate to rise accordingly.

Elevated CSF lactate without a parallel elevation in
serum level indicates increased CSF glucose metabolism, which is usually due to bacterial or fungal
meningitis. In early or partially treated bacterial or
fungal meningitis, CSF cell count and glucose levels
may be similar to those found in viral meningitis or
noninfectious conditions. Lactate levels above 35
mg/dL rarely occur, however, unless the client has
bacterial or fungal meningitis. Lactate levels remain
elevated until the individual has received effective
antibiotic therapy for several days. Persistent elevation of CSF lactate levels indicates inadequate treatment of meningitis.16
Urea levels in CSF and blood are approximately
equal; thus, CSF urea levels rise when blood levels
are elevated, as in uremia. Urea is sometimes administered intravenously (IV) to lower intracranial pressure. In such cases, the subsequent elevation in CSF
urea levels causes fluid to shift from the brain to the
CSF. CSF urea levels may remain elevated for 24 to
48 hours after IV administration of urea. Glutamine
is synthesized in the CNS from ammonia and
glutamic acid. CSF glutamine levels rise when blood
ammonia levels are high, a situation seen in cirrhosis with altered hepatic blood flow and encephalopathy. Glutamine levels in CSF have been found to
correlate as well or better than blood ammonia levels
with the degree of hepatic encephalopathy. Enzymes
that have been measured in CSF include lactic dehydrogenase (LDH), alanine aminotransferase (ALT,
SGPT), and aspartate aminotransferase (AST,
SGOT). Levels of these enzymes are normally lower
than those found in the blood. CSF enzymes may
rise in inflammatory, hemorrhagic, or degenerative
diseases of the CNS. CSF enzyme levels are not
measured under routine conditions, however, and
may not add to the diagnostic information obtained
from more routinely available tests.17
INTERFERING FACTORS

Delay in transporting sample to the laboratory
(may cause spurious discoloration as a result of
lysis of any red cells present, disintegration of any
neutrophils present, and false decrease in glucose
as a result of continued utilization by cells in the
sample)
Blood in the sample caused by traumatic tap
(adds one to two white cells and 1 mg/dL of
protein for every 1000 red cells per cubic millimeter contained in the sample)
INDICATIONS FOR ROUTINE CEREBROSPINAL
FLUID ANALYSIS

Suspected viral meningitis, cerebral thrombosis,
or brain tumor as indicated by a cell count of 10
to 200 per cubic millimeter, consisting mostly of

CHAPTER 8—Cerebrospinal

Fluid Analysis

277

Reference Values
Conventional Units
Color

SI Units

Clear

Pressure
Children

50–100 mm H2O

Adults

75–200 mm H2O (120 mm H2O average)

Cell count and differential
Children

Up to 20 small lymphocytes per cubic millimeter

Adults

Up to 5 small lymphocytes per cubic millimeter
No RBC or granulocytes

Protein
Total proteins
Infants

30–100 mg/dL

0.30–1.0 g/L

Children

14–45 mg/dL

0.14–0.45 g/L

Adults

15–45 mg/dL (lumbar area) or less
than 1% of serum levels

0.15–0.45 g/L

A-G ratio

8:1

IgG

3–12% of total protein

Glucose
Infants

20–40 mg/dL

1.11–2.22 mmol/L

Children

35–75 mg/dL

1.94–4.16 mmol/L

Adults

40–80 mg/dL or less than 50–80% of blood
glucose level 30–60 min earlier

2.22–4.44 mmol/L

Chloride

118–132 mEq/L

118–132 mmol/L

Calcium

2.1–2.7 mEq/L

1.05–1.35 mmol/L

Sodium

144–154 mEq/L

144–154 mmol/L

Potassium

2.4–3.1 mEq/L

2.4–3.1 mmol/L

Lactic acid (lactate)

10–20 mg/dL

1.1–2.2 mmol/L

Urea

10–15 mg/dL

3.6–5.3 mmol/L

Glutamine

Less than 20 mg/dL

1370.0 mol/L

Lactic dehydrogenase (LDH)

1/10 that of serum level

Electrolytes

lymphocytes, a mild elevation (to 300 mg/dL) in
total proteins, and normal or slightly decreased
glucose level
Suspected multiple sclerosis or neurosyphilis as
indicated by a normal or slightly elevated cell
count, consisting mostly of lymphocytes, slightly
elevated protein (less than 100 mg/dL), slightly

elevated globulins, elevated IgG on protein electrophoresis, and a normal or slightly decreased
glucose level
Suspected acute bacterial or syphilitic meningitis,
herpes infection of CNS as indicated by a cell
count of greater than 500 per cubic millimeter,
consisting largely of granulocytes, moderate or

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SECTION I—Laboratory

Tests

pronounced elevation in protein (greater than 300
mg/dL), pronounced decrease in glucose, and
decreased chloride18
Suspected tuberculous meningitis as indicated by
a cell count of 200 to 500 per cubic millimeter,
consisting of lymphocytes or mixed lymphocytes
and granulocytes, moderate or pronounced
elevation in proteins, pronounced reduction in
glucose, and decreased chloride
Suspected early bacterial or fungal meningitis as
indicated by CSF lactate level above 35 mg/dL,
even when cell count and glucose level are only
slightly altered
Evaluation of effectiveness of treatment for bacterial or fungal meningitis, with effective treatment
indicated by decreasing lactate levels after several
days of antimicrobial therapy
Suspected CNS leukemia as indicated by a cell
count of 200 to 500 per cubic millimeter, consisting mainly of blast cells and a moderate reduction
in glucose
Suspected spinal cord tumor as indicated by a cell
count of 10 to 200 per cubic millimeter, moderate
or pronounced elevation in protein, and normal
or slightly decreased glucose
Support for diagnosing subarachnoid hemorrhage as indicated by the presence of red blood
cells, elevated proteins, and a moderate reduction
in glucose
Support for diagnosing hepatic encephalopathy as
indicated by elevated glutamine levels
Support for diagnosing Guillain-Barré syndrome
(ascending polyneuritis) as indicated by pronounced elevation in proteins
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician and requires 20 to 30 minutes
The positioning used for the procedure and the
necessity of remaining still while the procedure is
being performed
That a local anesthetic will be injected at the
needle insertion site
That the needle is inserted below the end of the
spinal cord (for lumbar punctures)
That a sensation of pressure may be felt when the
needle is inserted
The necessity of remaining flat in bed for 6 to 8
hours after the procedure (for lumbar punctures)
and that turning from side to side is permitted as
long as the head is not raised
That taking fluids after the procedure will aid in
returning the CSF volume to normal (provided
that this is not contraindicated for the particular
client)

Prepare the client for the procedure:
Have the client void.
Provide a hospital gown.
Take and record vital signs, assess legs for neurological status (strength, movement, and sensation) for comparison with postprocedure
assessment.
Obtain a signed informed consent if required by
the agency.
THE PROCEDURE

The necessary equipment is assembled (e.g., lumbar
puncture tray). The client is assisted to a side-lying
position, with the head flexed as far as comfortable
and the knees drawn up toward, but not pressing on,
the abdomen. Support in maintaining this position
may be provided by placing one hand on the back of
the client’s neck and the other behind the knees.
Lumbar punctures may also be performed with the
client seated while leaning forward with arms resting
on an overbed table or other support.
The lumbar area is cleansed with an antiseptic
and protected with sterile drapes. The skin is infiltrated with a local anesthetic and the spinal needle
with stylet is inserted into a vertebral interspace
between L2 to S1, usually L3–4 or L4–5. The stylet is
then removed and, if the needle is properly positioned in the subarachnoid space, spinal fluid will
drip from the needle. A sterile stopcock and
manometer are then attached to the needle. The
opening pressure is read (see earlier discussion) and,
if indicated, Queckenstedt’s test is performed. When
the needle and manometer are properly positioned,
the CSF level should fluctuate several millimeters
with respiration.19
Queckenstedt’s test is based on the principle that
a change in pressure in one area of the closed
system—composed of the ventricular spaces,
intracranial subarachnoid space, and vertebral
subarachnoid space—will be reflected in other areas
of the system as well. The test is indicated when total
or partial spinal block (e.g., due to tumor) is
suspected, and it is performed by compressing both
jugular veins while monitoring lumbar CSF pressure. Temporary occlusion of the jugular veins
impairs the absorption of intracranial fluid and
produces an acute rise in CSF pressure. If CSF flow
is unimpeded, the pressure elevation will be transmitted to the lumbar area, and the fluid level in the
manometer will rise. Total or partial spinal block is
diagnosed if the CSF pressure fails to rise or if more
than 20 seconds is required for the pressure to return
to the pretest level after pressure on the jugular veins
is released. Queckenstedt’s test is risky in clients with
increased intracranial pressure of highly reactive
carotid body receptors. Radiologic examinations

CHAPTER 8—Cerebrospinal

such as myelograms and computed axial tomography (CAT) scans may give more information and
carry less risk.20
The manometer is then removed and CSF is
allowed to drip into three sterile test tubes, 3 to 10
mL per tube. The tubes are numbered in order of
filling, labeled with the client’s name, and sent to the
laboratory immediately. The manometer may then
be reattached and the closing pressure recorded. The
spinal needle is removed, and pressure is applied to
the site. If no excessive bleeding or CSF leakage is
noted, an adhesive bandage is applied to the site and
the client is assisted to a recumbent position.
Alternatives to the lumbar puncture include
cisternal and ventricular punctures. These procedures may be used when lumbar puncture is not
feasible because of bony abnormalities or infection
at the lumbar area. For a cisternal puncture, the
client is assisted to a side-lying position with the
neck flexed and the head resting on the chest. The
back of the neck may require shaving before the
procedure. After the skin is infiltrated with local
anesthetic, the needle is inserted at the base of the
occiput, between the first cervical vertebra and the
foramen magnum. CSF samples are then obtained in
the same manner as for lumbar punctures. Cisternal
punctures are considered somewhat hazardous,
because the needle is inserted close to the brainstem;
however, clients are said to be less likely to experience postprocedure headaches and may resume
usual activities within a few hours of the procedure.21
Ventricular punctures are surgical procedures
(i.e., usually performed in an operating room) in
which CSF samples are obtained directly from one of
the lateral ventricles in the brain. For this procedure,
a scalp incision is made and a burr hole is drilled in
the occipital area of the skull. The needle is then
inserted through the hole and into the lateral ventricle, and CSF samples are obtained. This procedure is
rarely performed.22
The cell count and protein content of CSF
samples obtained by cisternal or ventricular punctures are normally lower than those found in lumbar
samples. The higher levels of cells and protein found
in CSF from lumbar punctures are thought to be
caused by stagnation of CSF, which occurs in the
lumbar sac.23
NURSING CARE DURING THE PROCEDURE

Note any distress, especially dyspnea, that may be
caused by positioning.
Observe for signs of brainstem herniation such as
decreased level of consciousness, irregular respirations, and a unilaterally dilating pupil (uncal
herniation).

Fluid Analysis

279

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to a recumbent position and
having the client maintain a flat position for 6 to 8
hours to prevent the occurrence of headache.
Remind the client that turning from side to side is
permitted, as long as the head is not raised.
Assist the client in taking liberal amounts of
fluids to replace the CSF loss, unless otherwise
contraindicated.
A dressing can be applied after pressure to the
puncture site.
Care after cisternal and ventricular punctures is
essentially the same as that for lumbar punctures.
For cisternal punctures, provide bed rest for only
2 to 4 hours, after which usual activities may be
resumed. For ventricular punctures, maintain bed
rest for 24 hours.
Take and record vital signs every hour for the first
4 hours and then every 4 hours for 24 hours (for
hospitalized clients).
Perform a neurological check each time vital signs
are taken to determine nerve damage affecting the
legs.
Assess the puncture site for bleeding, CSF
drainage, and inflammation each time vital signs
are taken during the first 24 hours and daily thereafter for several days. (Family members or
support persons should be instructed to do this
for nonhospitalized clients.)
Observe for signs of meningeal irritation such as
fever, nuchal rigidity, and irritability indicating
infection.
Assess the client’s comfort level, noting presence
or absence of headache. Administer an ice bag to
the head and a mild analgesic if ordered.

MICROBIOLOGIC EXAMINATION
OF CEREBROSPINAL FLUID
Microbiologic studies of CSF include C&S, Gram
stain and other stains, AFB smear and culture, and
the Limulus assay for gram-negative bacteria.
Numerous microorganisms can cause meningitis,
encephalitis, and brain abscess. Thus, whenever CNS
infection is suspected, CSF should be tested for the
presence of bacteria, fungi, protozoa, and tubercle
bacilli, because more than one organism may be
present.24 The CSF is also tested for bacterial antigens in addition to culturing for bacteria. CSF rarely
contains abundant organisms, so specimens for
microbiologic examination must be collected and
handled with strict aseptic technique. The usual
laboratory procedure is to centrifuge a few milliliters
of CSF to concentrate any organisms present. After

280

SECTION I—Laboratory

Tests

culture plates with several different media are inoculated, the remaining CSF sediment is examined
with Gram staining and AFB staining techniques
(see Chapter 7).25
Failure to isolate organisms on stained smear does
not necessarily mean that organisms are absent from
the CSF sample. Reliably positive results are
obtained only when at least 105 bacteria per milliliter
are present. Gram stains, for example, are positive in
only 80 to 90 percent of individuals with untreated
meningitis. CSF is almost routinely examined and
cultured for AFB when the cause of the CNS disorder is unknown, because tuberculous meningitis can
develop insidiously and presents with few clear diagnostic indicators.26
When infection with the fungus Cryptococcus is
suspected, the specimen may be examined by testing
for cryptococcal antigen.27 The cryptococcal antigen
test, in which a strong anticryptococcal antibody is
used, may elicit antigenic elements even when cryptococcal organisms are undetected by other methods.28
Amebae may also cause meningitis, especially in
individuals who swim in lakes or indoor swimming
pools. A wet-mount preparation of CSF is examined
for motile cells when such an infection is suspected.29
Spinal fluid is normally cultured on several different media to test for different organisms. The
meningococcal organism (Neisseria meningitidis),
for example, prefers to grow in a medium with
a high carbon dioxide atmosphere. Counterimmunoelectrophoresis (CIEP) can also be used to detect
bacterial antigens when usual techniques fail to
demonstrate bacteria in CSF.30
The presence of gram-negative organisms in CSF
can be demonstrated rapidly with the Limulus assay.
This test uses the bloodlike fluid of the horseshoe
crab of the genus Limulus, which is coagulated by
gram-negative endotoxins. This test, therefore,
provides a quick means of diagnosing gram-negative
infections of the CNS and gram-negative endotoxemia. The test is more reliable when performed on
CSF than when performed on blood.31
Acute bacterial meningitis occurs most
commonly in children younger than age 5 years and
in adults who have experienced head trauma. Gramnegative bacilli (Escherichia coli, Klebsiella,
Enterobacter, Proteus) are the usual etiologic agents
of meningitis in premature infants and newborns. In
infants, the causative agents include Streptococcus
agalactiae (group B) and Listeria monocytogenes. In
young children, meningitis is most frequently
caused by gram-negative bacilli (Haemophilus
influenzae). In adolescents, the agent is most likely to

be N. meningitidis. In adults, meningitis may also be
caused by Streptococcus pneumoniae. In elderly
persons, the agent is a gram-negative bacillus. Viral
infections, tuberculous meningitis, and fungal and
protozoal infections may occur at any age and often
present as insidious or misleading syndromes.32
Reference Values
Organisms are not normally present in CSF.

INTERFERING FACTORS

Delay in transporting the sample to the laboratory
(Organisms may disintegrate if the sample is held
at room temperature for more than 1 hour.)
Contamination of the sample with normal skin
flora or other organisms because of improper
collection or handling of the sample
INDICATIONS FOR MICROBIOLOGIC EXAMINATION
OF CEREBROSPINAL FLUID

Suspected meningitis, encephalitis, or brain
abscess
CNS disorder of unknown etiology without clear
diagnostic indicators
Head trauma with possible resultant CNS infection
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of CSF samples (see section
under “Routine Cerebrospinal Fluid Analysis”).
THE PROCEDURE

The procedures for obtaining the specimen are the
same as those described in the “Routine Cerebrospinal Fluid Analysis” section. Extreme care must
be used in obtaining and collecting the sample, so as
not to contaminate the sample or introduce organisms into the CNS.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of a CSF
sample (see section under “Routine Cerebrospinal
Fluid Analysis”).
Depending on the nature of the suspected or
confirmed infection, use infectious disease
precautions.
Complications and precautions: Note and report
signs and symptoms of brain disorder such as
fever, irritability, or headache. Perform neurological checks and take and record vital signs. Notify
physician immediately of a positive stain result.

CHAPTER 8—Cerebrospinal

CYTOLOGIC EXAMINATION OF
CEREBROSPINAL FLUID
Cytologic examination of CSF is performed primarily to detect malignancies involving the CNS.
Cellular changes caused by malignancies whose
primary site is the CNS (e.g., brain tumors) or
malignancies that have metastasized to the CNS
from other sites (e.g., breast and lung) may be
detected. Abnormal cells resulting from acute
leukemia involving the CNS may also be seen.
Reference Values

Fluid Analysis

281

ment fixation tests and the Venereal Disease
Research Laboratory (VDRL) and rapid plasma
reagin (RPR) flocculation tests. The best specific test
is the fluorescent treponemal antibody (FTA) test.
Nonspecific reagin tests are usually used for
routine testing of CSF because they are cheaper and
more readily available than the FTA test. The falsepositive results that can occur when blood is tested
with reagin tests occur fairly rarely in CSF specimens. Nonspecific tests are, however, less sensitive
than the FTA test. Thus, if neurosyphilis is a serious
diagnostic consideration, the FTA is the test of
choice.33

No abnormal cells
Reference Values
INTERFERING FACTORS

Delay in transporting the sample to the laboratory
(Cells may disintegrate if the sample is held at
room temperature for more than 1 hour.)
Contamination of the sample with skin cells
INDICATIONS FOR CYTOLOGIC EXAMINATION
OF CEREBROSPINAL FLUID

Suspected malignancy with primary site in the
CNS
Suspected metastasis of malignancies to the CNS
Suspected CNS involvement in acute leukemia
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of CSF samples (see section
under “Routine Cerebrospinal Fluid Analysis”).
THE PROCEDURE

The procedures for obtaining the specimen are the
same as those described in the “Routine Cerebrospinal Fluid Analysis” section. Care must be
taken not to contaminate the sample with skin cells.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of a CSF
sample (see section under “Routine Cerebrospinal
Fluid Analysis”).

SEROLOGIC TESTS FOR NEUROSYPHILIS
When syphilis involving the CNS (neurosyphilis) is
suspected, serologic tests are performed on samples
of CSF. Blood tests for syphilis (see Chapter 3)
consist of two main types: (1) nonspecific tests that
demonstrate syphilitic reagin and (2) specific tests
that demonstrate antitreponemal antibodies. Reagin
tests include the Wassermann and Reiter comple-

Negative
INTERFERING FACTORS

Delay in transporting the sample to the laboratory
(Organisms may disintegrate if the sample is held
at room temperature for more than 1 hour.)
INDICATIONS FOR SEROLOGIC TESTS FOR
NEUROSYPHILIS

Suspected neurosyphilis
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for any test
involving the collection of CSF samples (see section
under “Routine Cerebrospinal Fluid Analysis”).
THE PROCEDURE

The procedures for obtaining the specimen are the
same as those described in the “Routine
Cerebrospinal Fluid Analysis” section.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any test involving the collection of a CSF
sample (see section under “Routine Cerebrospinal
Fluid Analysis”).
REFERENCES
1. Porth, CM. Pathophysiology: Concepts of Altered Health, ed 5. JB
Lippincott, Philadelphia, 1998, pp 868–869.
2. Ibid, p 868.
3. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, p 537.
4. Porth, op cit, p 870.
5. Sacher and McPherson, op cit, pp 731, 735.
6. Ibid, p 729.
7. Ibid, p 732.
8. Ibid, p 733.
9. Ibid, p 730.
10. Ibid, p 731.
11. Ibid, pp 732–733.

282

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Tests

12. Fischbach, FT: A Manual of Laboratory Diagnostic Tests, ed 4. JB
Lippincott, Philadelphia, 1992, p 255.
13. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 776.
14. Sacher and McPherson, op cit, p 735.
15. Ibid, p 735.
16. Ibid, p 733.
17. Ibid, pp 733, 735.
18. Ibid, pp 731–732.
19. Ibid, p 730.
20. Ibid, pp 730–731.
22. Nurse’s Reference Library, op cit, p 779.

23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.

Ibid, p 779.
Sacher and McPherson, op cit, p 732.
Ibid, p 735.
Ibid, p 495.
Ibid, p 735.
Ibid, p 735.
Ibid, p 735.
Ibid, p 735.
Ibid, p 735.
Ibid, p 734.
Ibid, p 734
Ibid, p 736.

CHAPTER

Analysis of Effusions
TESTS COVERED
Pericardial Fluid Analysis, 284
Pleural Fluid Analysis, 286

Peritoneal Fluid Analysis, 289
Synovial Fluid Analysis, 292

OVERVIEW OF EFFUSIONS Effusions are excessive accumulations of fluid in body cavities lined with serous or synovial membranes. Such cavities normally contain only small
amounts of fluid (i.e., less than 50 mL). Serous membranes line the closed cavities of the thorax
and abdomen and cover the organs within them. Membranes lining cavities are termed parietal
membranes; membranes covering organs are called visceral membranes. Serous membranes
consist of a layer of simple squamous epithelium (mesothelium) that covers a thin layer of
connective tissue.1 Serous membranes secrete a small amount of watery fluid into the potential
space between the parietal and visceral membranes. Serous fluid serves as a lubricant, allowing
the internal organs to move without excessive friction. Although there is no actual space
between visceral and parietal serous membranes, the potential space between them is called a
cavity. In certain disease states, these cavities may contain large amounts of fluid (i.e., effusions). Three such serous cavities are the pericardial cavity, the pleural cavity, and the peritoneal
cavity.
Synovial membranes line the cavities of most joints, the bursae, and the synovial tendon
sheaths. These membranes consist of fibrous connective tissue, which overlies loose connective
tissue and adipose tissue.2 Synovial cells are found in layers one to three cells thick; wide gaps
are often found between adjacent synovial cells. Synovial membranes secrete a thick, colorless
fluid with a high mucin content. As with serous fluid, synovial fluid acts as a lubricant in joint
cavities. It also provides nourishment to articular cartilage.3
Serous fluid is formed by diffusion from adjacent capillaries via interstitial fluid and may be
described as an ultrafiltrate of plasma. Thus, substances that normally diffuse from capillaries
(e.g., water, electrolytes, glucose) diffuse into serous fluid. Similarly, substances can diffuse from
serous fluid back into the capillaries. Protein may also collect in serous cavities because of capillary leakage. Protein and excess fluids are normally removed from these cavities by the
surrounding lymphatics.
Synovial fluid is formed in a manner similar to that of serous fluid but additionally contains
a hyaluronate–protein complex (i.e., a mucopolysaccharide containing hyaluronic acid and a
small amount of protein) that is secreted by the connective tissue cells of the synovial
membrane.4 As with serous cavities, excess proteins and fluids are normally drained from
synovial cavities by the lymphatics.
Changes in fluid production and drainage can lead to the development of effusions in serous
and synovial cavities. Mechanical factors that can cause effusions include increased capillary
permeability, increased capillary hydrostatic pressure, decreased capillary colloidal osmotic
pressure, increased venous pressure, and blockage of lymphatic vessels. Damage to the serous
283

284

SECTION I—Laboratory

Tests

and synovial membranes (e.g., caused by inflammation or infection) can also cause excessive
fluid buildup.
Effusions involving serous cavities may be differentiated as transudates or exudates.
Transudates occur because of abnormal mechanical factors and are generally characterized by
low-protein, cell-free fluids. Exudates are caused by infection or inflammation and contain cells
and excessive amounts of protein. Pleural and peritoneal effusions can be either transudates or
exudates; pericardial effusions, however, are almost always exudates.5 Chylous effusions caused
by the escape of chyle from the thoracic lymphatic duct may form in the pleural and peritoneal
cavities. Accumulation of large amounts of fluid in the peritoneal cavity is termed ascites.
Samples of effusions for laboratory analysis are obtained by needle aspiration. Centesis is a
suffix denoting “puncture and aspiration of.”6 Thus, aspiration of pericardial fluid is called pericardiocentesis, aspiration of pleural fluid is called thoracentesis, aspiration of peritoneal fluid is
called paracentesis, and aspiration of synovial fluid is called arthrocentesis.
Serous fluids are normally clear and pale yellow, occurring in amounts of 50 mL or less in the
pericardial and peritoneal cavities and 20 mL or less in the pleural cavity. Cloudy (turbid) fluid
suggests an inflammatory process that may be caused by infection. Milky fluid is associated with
chylous effusions or chronic serous effusions (pseudochylous effusions). Bloody fluid may indicate a hemorrhagic process or a traumatic tap. Bloody pericardial fluid is associated with a
number of disorders, including hemorrhagic and bacterial pericarditis, postmyocardial infarction and postpericardiectomy syndromes, metastatic cancer, aneurysms, tuberculosis, systemic
lupus erythematosus (SLE), and rheumatoid arthritis. Bloody pleural effusions are most often
the result of malignancies involving the lung but may also be seen in pneumonia, pulmonary
infarction, chest trauma, pancreatitis, and postmyocardial infarction syndrome. Bloody pleural
transudates also have been noted in congestive heart failure (CHF) and cirrhosis of the liver.
Bloody peritoneal fluid is associated primarily with malignant processes and abdominal
trauma. Greenish peritoneal fluid is seen in perforated duodenal ulcers, intestines, and gallbladders, as well as with cholecystitis and acute pancreatitis.7
As with serous fluid, synovial fluid is normally clear and pale yellow, occurring in amounts
of approximately 3 mL or less per joint cavity. Synovial fluid is more viscous than serous fluid
because of the presence of the hyaluronate–protein complex secreted by the synovial cells.
Arthritis and other inflammatory conditions involving the joints may affect the production of
hyaluronate and lead to decreased viscosity of synovial fluid. The mucin clot test (Ropes test),
in which synovial fluid is added to a 2 to 5 percent acetic acid solution, can be used to assess the
viscosity of synovial fluid in relation to the type of clot formed (e.g., solid, soft, friable, or
none).8 This test, however, is not as accurate as specific synovial fluid cell counts and other
analyses.9
Cloudy synovial fluid suggests an inflammatory process. Substances such as crystals, fibrin,
amyloid, and cartilage fragments can also result in cloudy synovial fluid. Milky synovial fluid is
associated with various types of arthritis as well as with SLE. Purulent fluid may be seen in acute
septic arthritis, whereas greenish fluid may occur in Haemophilus influenzae septic arthritis,
chronic rheumatoid arthritis, and acute synovitis caused by gout. Bloody synovial fluid may be
the result of a traumatic tap but is most commonly associated with fractures or tumors involving the joint and traumatic or hemophilic arthritis.10
Tests of serous and synovial effusions include cell count and differential, measurement of
substances normally found in the fluid (e.g., glucose), culture and sensitivity (C&S) testing, and
cytologic examination. These tests are discussed subsequently in relation to the cavity from
which the fluid is obtained.

TESTS OF EFFUSIONS
PERICARDIAL FLUID ANALYSIS
Pericardial effusions are most commonly caused by
pericarditis, malignancy, or metabolic damage. As
noted previously, most pericardial effusions are

exudates. Tests commonly performed on pericardial
fluid include red cell count, white cell count and
differential, determination of glucose level, and
cytologic examination. Gram stains and cultures of
pericardial fluid are not routinely performed unless
bacterial endocarditis is suspected.11

CHAPTER 9—Analysis

of Effusions

285

Reference Values
Red blood cells

None normally present

White blood cells

1000/mm3

Glucose

80–100 mg/dL or essentially the same as the blood
glucose level drawn 2–4 hr earlier

Cytologic examination

No abnormal cells

Gram stain and culture

No organisms present

Critical values

Positive Gram stain or culture

Cytologic examination of pericardial fluid is
undertaken to detect malignant cells. Gram stain
and culture reveal the causative agent when infection
is suspected.
INTERFERING FACTORS

Blood in the sample because of traumatic pericardiocentesis
Undetected hypoglycemia or hyperglycemia
Contamination of the sample with skin cells and
pathogens
INDICATIONS FOR PERICARDIAL FLUID ANALYSIS

Pericardial effusion of unknown etiology
Suspected hemorrhagic pericarditis as indicated
by the presence of red cells and an elevated white
cell count
Suspected bacterial pericarditis as indicated by
the presence of red cells, elevated white cell
count with a predominance of neutrophils, and
decreased glucose
Suspected postmyocardial infarction syndrome
(Dressler’s syndrome) as indicated by the presence of red cells and elevated white cell count with
a predominance of neutrophils
Suspected tuberculous or fungal pericarditis as
indicated by the presence of red cells and an
elevated white cell count with a predominance of
lymphocytes
Suspected viral pericarditis as indicated by the
presence of red cells and an elevated white cell
count with neutrophils predominating
Suspected rheumatoid disease or SLE as indicated
by the presence of red cells, elevated white cell
count, and decreased glucose levels
Suspected malignancy as indicated by the presence of red cells, decreased glucose, and presence
of abnormal cells on cytologic examination
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician and will require approximately 20 minutes

Where the test will be performed (i.e., it is sometimes performed in the cardiac laboratory)
Any dietary restrictions (fasting for 6 to 8 hours
before the test may be required)
That an intravenous (IV) infusion will be started
before the procedure and discontinued afterward
That a sedative may be administered before the
procedure
That the skin will be injected with a local anesthetic at the chest needle insertion site and that
this may cause a stinging sensation
That, after the skin has been anesthetized, a needle
will be inserted through the chest wall below and
slightly to the left of the breast bone into the fluidfilled sac around the heart
That a sensation of pressure may be felt when the
needle is inserted to obtain the pericardial fluid
That heart rate and rhythm will be monitored
during the procedure
The importance of remaining still during the
procedure
Any activity restrictions after the test (usually a
few hours of bed rest)
Prepare for the procedure:
Withhold anticoagulant medications and aspirin
as ordered.
Have the client void.
Provide a hospital gown.
Take and record vital signs.
Administer premedication as ordered.
THE PROCEDURE (PERICARDIOCENTESIS)

The necessary equipment is assembled, including a
pericardiocentesis tray with solution for skin preparation, local anesthetic, 50-mL syringe, needles of
various sizes including a cardiac needle, sterile
drapes, and sterile gloves. Sterile test tubes (same as
those used for collecting blood samples) also are
needed; at least one red-topped, one green-topped,
and one lavender-topped tube should be available.
Containers for culture and cytologic analysis of pericardial fluid samples may also be needed. Cardiac
monitoring equipment should be obtained, along

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with an alligator clip for attaching a precordial (V)
lead to the cardiac needle.
The client is assisted to a supine position with the
head elevated 45 to 60 degrees. The limb leads for
the cardiac monitor are attached to the client, and
the IV infusion is started. The skin is cleansed with
an antiseptic solution and protected with sterile
drapes. The skin at the needle insertion site is then
infiltrated with local anesthetic. Strict aseptic technique is used during the entire procedure.
The precordial (V) cardiac lead wire is attached to
the hub of the cardiac needle with the alligator clip.
The needle is then inserted just below and slightly to
the left of the xiphoid process. Gentle traction is
sustained on the plunger of the 50-mL syringe until
fluid appears, indicating that the needle has entered
the pericardial sac. Fluid can be aspirated with ultrasound guidance. Fluid samples are then withdrawn
and placed in appropriate tubes. The samples are
labeled and sent promptly to the laboratory.
When the desired samples have been obtained,
the cardiac needle is withdrawn. Pressure is applied
to the site for 5 minutes. If there is no evidence of
bleeding or other drainage, a sterile bandage is
applied. If the client’s cardiac rhythm is stable,
cardiac monitoring is discontinued.
NURSING CARE DURING THE PROCEDURE

Observe the client for respiratory or cardiac distress.
Possible complications of a pericardiocentesis
include cardiac dysrhythmias (atrial or ventricular),
laceration of the pleura, laceration of the cardiac
atrium or coronary vessels, injection of air into a
cardiac chamber, and contamination of pleural
spaces with infected pericardial fluid.
Monitor the electrocardiograph for position of
the needle tip to note any puncture of the right
atrium.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to a position of comfort and
reminding the client of any activity restrictions.
Resume any foods or fluids withheld before the
test and any medications withheld on the physician’s order.
Continue IV fluids until vital signs are stable and
the client is able to resume normal fluid intake.
Take and record vital signs as for a postoperative
client (i.e., every 15 minutes for the first hour,
every 30 minutes for the second hour, every hour
for the next 4 hours, and then every 4 hours for 24
hours). Assess for abnormalities in ECG patterns.
Assess the puncture site for bleeding, hematoma
formation, and inflammation each time vital signs

are taken and daily thereafter for several days.
Observe the client for any cardiac or respiratory
distress.
Provide support when diagnostic findings are
revealed.
Note relief of symptoms of cardiac tamponade or
pericarditis: absence of distended neck veins;
normal cardiac output, heart rate, and heart
sounds; absence of chest pain and pulsus paradoxus.
Administer antibiotics specific to the causative
agent and anti-inflammatory drugs to reduce the
inflammatory response.
Notify physician immediately if the Gram stain
and culture are positive.

PLEURAL FLUID ANALYSIS
Pleural effusions are most commonly caused by
CHF, hypoalbuminemia (e.g., resulting from cirrhosis of the liver), hypoproteinemia (e.g., resulting
from nephrotic syndrome), neoplasms, and
pulmonary infections (e.g., pneumonia, tuberculosis). Other causes include trauma and pulmonary
infarctions, both of which are associated with
hemorrhagic effusions, rheumatoid disease, SLE,
pancreatitis, and ruptured esophagus. Chylous pleural effusions occur when damage or obstruction to
the thoracic lymphatic duct has occurred. Pleural
effusions can be either transudates or exudates.
Tests commonly performed on pleural fluid
include red cell count, white cell count and differential, Gram stain, C&S, and cytologic examination.
The pH of the sample is usually determined, and the
fluid is tested for levels of glucose, protein, lactic
dehydrogenase (LDH), and amylase. Triglycerides
and cholesterol may also be measured when chylous
effusion is suspected.
Gram stain and C&S tests are generally performed
to identify the causative organism when infection is
suspected. Cytologic examination is undertaken to
detect malignant cells.
Pleural effusions may also be tested for levels of
immunoglobulins, complement components, and
carcinoembryonic antigen (CEA) (see Chapter 3)
when disorders of immunologic and malignant
origin are suspected. Elevated immunoglobulins and
CEA or decreased complement levels, or both, are
seen in inflammatory or neoplastic reactions involving the pleural membranes.12
INTERFERING FACTORS

Blood in the sample because of traumatic thoracentesis
Undetected hypoglycemia or hyperglycemia

CHAPTER 9—Analysis

of Effusions

287

Reference Values
Red blood cells

0–1000/mm3

White blood cells

0–1000/mm3, consisting mainly of lymphocytes

Gram stain and culture

No organisms present

Cytologic examination

No abnormal cells

7.37–7.43 (usually 7.40)

Glucose

Parallels serum levels

Protein

3.0 g/dL

Pleural fluid:serum protein ratio

0.5 or less

Lactic dehydrogenase

71–207 IU/L

Pleural fluid:serum LDH ratio

0.6 or less

Amylase

180 Somogyi U/dL or 200 dye U/dL

Triglycerides
Cholesterol
Immunoglobulins
Carcinoembryonic antigen (CEA)
Complement
Critical values

Parallel serum levels

Positive Gram stain or culture

Contamination of the sample with skin cells and
pathogens
INDICATIONS FOR PLEURAL FLUID ANALYSIS

Pleural effusion of unknown etiology
Differentiation of pleural transudates from
exudates (Table 9–1)
Suspected traumatic hemothorax as indicated by
bloody pleural fluid, elevated red cell count, and
hematocrit similar to that found in whole blood
Suspected pleural effusion caused by pulmonary
tuberculosis as indicated by presence of red blood
cells (fewer than 10,000 per cubic millimeter);
white cell count of 5,000 to 10,000 per cubic
millimeter, consisting mostly of lymphocytes;
presence of acid-fast bacilli (AFB) on smear and
culture; pH of less than 7.30, decreased glucose
(sometimes); and elevated protein, pleural
fluid:serum protein ratio, LDH, and pleural
fluid:serum LDH ratio
Suspected pleural effusion caused by pneumonia
(parapneumonic effusion) as indicated by presence of red blood cells (5,000 per cubic millimeter); white cell count of 5,000 to 25,000 per cubic
millimeter, consisting mainly of neutrophils and
sometimes including eosinophils; pH less than
7.40; and elevated protein, pleural fluid:serum

protein ratio, LDH, and pleural fluid:serum LDH
ratio. (If the pneumonia is of bacterial origin, the
organism may be demonstrated on culture and
the pleural fluid glucose level may be decreased.)
Suspected bacterial or tuberculous empyema as
indicated by red cell count of less than 5,000 per
cubic millimeter; white cell count of 25,000 to
100,000 per cubic millimeter, consisting mostly of
neutrophils; pH less than 7.30; decreased glucose;
and increased protein, LDH, and related ratios13
Suspected pleural effusion caused by carcinoma as
indicated by presence of red blood cells (1,000 to
more than 100,000 per cubic millimeter); white
cell count of 5,000 to 10,000 per cubic millimeter,
consisting mostly of lymphocytes and sometimes
including eosinophils; detection of malignant
cells on cytologic examination; pH less than
7.30; decreased glucose (sometimes); increased
protein, LDH, and related ratios; elevated CEA
and immunoglobulins; and decreased complement14
Suspected pleural effusion caused by pulmonary
infarction as indicated by red cell count of 1,000
to 100,000 per cubic millimeter; white cell count
of 5,000 to 15,000 per cubic millimeter, consisting
mainly of neutrophils and sometimes including
eosinophils; pH greater than 7.30; normal

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SECTION I—Laboratory

TABLE 9–1

•

Tests

Differentiation of Pleural Transudates From Exudates
Transudates

Exudates

Appearance

Clear

Cloudy; may be bloody

Red blood cells

1000/mm

1000/mm3 (usually)

White blood cells

1000/mm3

7.40 or higher

7.40

Glucose

Parallels serum level

May be less than serum level

Protein

3.0 g/dL

Pleural fluid:serum protein ratio

0.5

Lactic dehydrogenase

200 IU/L

Pleural fluid:serum LDH ratio

0.6

Common causes

Congestive heart failure

Pneumonia

Cirrhosis

Tuberculosis

Nephrotic syndrome

Empyema
Pulmonary infarction
Rheumatoid disease
Systemic lupus erythematosus
Carcinoma
Pancreatitis

glucose; and elevated protein, LDH, and related
ratios15
Suspected pleural effusion caused by rheumatoid
disease as indicated by a normal red cell count; a
white cell count of 1,000 to 20,000 per cubic
millimeter with either lymphocytes or neutrophils predominating; pH less than 7.30; decreased
glucose; elevated protein, LDH, and related ratios;
and elevated immunoglobulins16
Suspected pleural effusion caused by SLE as indicated by findings similar to those in rheumatoid
disease, except that glucose is not usually
decreased
Suspected pleural effusion caused by pancreatitis
as indicated by red cell count of 1,000 to 10,000
per cubic millimeter; white cell count of 5,000 to
20,000 per cubic millimeter, consisting mostly of
neutrophils; pH greater than 7.30; normal
glucose; elevated protein, LDH, and related ratios;
and elevated amylase
Suspected pleural effusion caused by esophageal
rupture as indicated primarily by a pH as low as
6.0 and elevated amylase17
Differentiation of chylous pleural effusions
caused by thoracic lymphatic duct blockage from
pseudochylous (chronic serous) effusions, with

chylous effusions indicated primarily by a triglyceride level two to three times that of serum;
decreased cholesterol; and markedly elevated
chylomicrons
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician and requires approximately 20 minutes
That there are no food or fluid restrictions before
the test
That a sedative is not usually given before the
procedure, although a cough suppressant may be
given to prevent coughing
The positioning used for the procedure
(supported sitting or side-lying)
That the skin will be injected with a local anesthetic at the chest needle insertion site and that
the injection may cause a stinging sensation
That, after the skin has been anesthetized, a needle
will be inserted through the posterior chest into
the space near the lungs where excessive fluid has
accumulated
That a sensation of pressure may be felt when the
needle is inserted
The importance of remaining still during the

CHAPTER 9—Analysis

procedure and the need to control breathing,
coughing, and movement
Any activity restrictions after the test (usually 1
hour of bed rest)
Prepare for the procedure:
Withhold anticoagulant medications and aspirin
as ordered.
Have the client void.
Provide a hospital gown.
Take and record vital signs.
Administer cough suppressant, if ordered.
THE PROCEDURE (THORACENTESIS)

The necessary equipment is assembled, including a
thoracentesis tray with solution for skin preparation,
local anesthetic, 50-mL syringe, needles of various
sizes including a thoracentesis needle, sterile drapes,
and sterile gloves. Sterile collection bottles and
containers for culture and cytologic examination
also are needed.
The client is assisted to the position that will be
used for the test. The usual position is sitting on the
side of a bed or treatment table, leaning slightly
forward to spread the intercostal spaces, with arms
supported on an overbed table with several pillows.
Alternatively, the client may sit on the bed or table
with legs extended on it and arms supported as
described earlier. If the client cannot assume either
sitting position, the side-lying position is used. In
such situations, the client lies on the unaffected side.
The skin is cleansed with an antiseptic solution
and protected with sterile drapes. The skin at the
needle insertion site is then infiltrated with local
anesthetic. The thoracentesis needle is inserted.
When fluid appears, a stopcock and 50-mL syringe
are attached to the needle and the fluid is aspirated.
The pleural fluid samples are placed in appropriate
containers, labeled, and sent promptly to the laboratory.
If the thoracentesis is being performed for therapeutic as well as diagnostic reasons, additional pleural fluid may be withdrawn. When the desired
amount of fluid has been removed, the needle is
withdrawn, and slight pressure is applied to the site
for a few minutes. If there is no evidence of bleeding
or other drainage, a sterile bandage is applied to the
site.
NURSING CARE DURING THE PROCEDURE

Observe the client for signs of respiratory distress or
pneumothorax (e.g., anxiety, restlessness, dyspnea,
cyanosis, tachycardia, and chest pain). Possible
complications of a thoracentesis include pneumothorax, mediastinal shift, and excessive reaccumulation of pleural fluid.

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289

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client in lying on the unaffected side
and reminding the client that this position should be
maintained for approximately 1 hour.
Elevate the head for client comfort.
Prepare for a post-thoracentesis chest x-ray examination ordered to ensure that a pneumothorax as
a result of the tap has not occurred and to evaluate the amount of fluid removed.
Take and record vital signs as ordered (e.g., every
15 minutes for the first half hour, every 30
minutes for the next hour, and then every 4 hours
for 24 hours or until stable).
Observe the client for respiratory distress or
hemoptysis, diaphoresis, or skin color changes.
Auscultate breath sounds. Absent or diminished
breath sounds on the side used for the thoracentesis may indicate pneumothorax.
Assess the puncture site for bleeding, hematoma
formation, and inflammation each time vital signs
are taken and daily thereafter for several days.
Provide support when diagnostic findings are
revealed and information is given about subsequent therapy based on the findings.
Note relief of chest pain, dyspnea, or diminished
breath sounds.
Note response to antibiotic or cytotoxic drugs if
injected into the cavity after fluid removal.
Notify physician immediately if the Gram stain or
culture is positive.

PERITONEAL FLUID ANALYSIS
Peritoneal transudates are most commonly caused
by CHF, cirrhosis of the liver, and nephrotic
syndrome. Peritoneal exudates occur with
neoplasms including metastatic carcinoma, infections (e.g., tuberculosis, bacterial peritonitis),
trauma, pancreatitis, and bile peritonitis. Chylous
peritoneal effusions occur when there is damage or
obstruction to the thoracic lymphatic duct.
Accumulation of large amounts of fluid in the peritoneal cavity is termed ascites, and the peritoneal
fluid is referred to as ascitic fluid.
Peritoneal fluid is removed by paracentesis or by
paracentesis and lavage with normal saline or
Ringer’s lactate. Lavage involves instilling the desired
solution over 15 to 20 minutes, then removing it and
analyzing it for cells and other constituents.
Tests commonly performed on peritoneal or
ascitic fluid include red cell count, white cell count
and differential, Gram stain, C&S, AFB smear and
culture, and cytologic examination. The fluid may

290

SECTION I—Laboratory

Tests

also be tested for glucose, amylase, ammonia, alkaline phosphatase, and CEA. Urea and creatinine may
be measured if there is suspicion of ruptured or
punctured urinary bladder.
Gram stain and C&S tests are generally performed
to identify the causative organism when infection is
suspected. If tuberculous effusion is suspected, an
AFB smear and culture can be performed, although
positive results are seen in only 25 to 50 percent
of cases.18 Cytologic examination is used to detect
malignant cells.
INTERFERING FACTORS

Blood in the sample as a result of traumatic paracentesis
Undetected hypoglycemia or hyperglycemia
Contamination of the sample with skin cells and
pathogens
INDICATIONS FOR PERITONEAL FLUID ANALYSIS

Ascites of unknown cause
Suspected peritoneal effusion caused by abdominal malignancy as indicated by elevated red cell
count, decreased glucose, elevated CEA, and
detection of malignant cells on cytologic examination
Suspected abdominal trauma as indicated by
elevated red cell count of greater than 100,000 per
cubic millimeter19

Suspected ascites caused by cirrhosis of the liver as
indicated by elevated white cell count, neutrophil
count of greater than 25 percent but less than 50
percent, and an absolute granulocyte count of less
than 250 per cubic millimeter
Suspected bacterial peritonitis as indicated by
elevated white cell count, neutrophil count
greater than 50 percent, and an absolute granulocyte count of greater than 250 per cubic
millimeter20
Suspected tuberculous peritoneal effusion as indicated by elevated lymphocyte count, positive AFB
smear and culture in about 25 to 50 percent of
cases, and decreased glucose
Suspected peritoneal effusion caused by pancreatitis, pancreatic trauma, or pancreatic pseudocyst
as indicated by elevated amylase levels
Suspected peritoneal effusion caused by gastrointestinal perforation, strangulation, or necrosis as
indicated by elevated amylase, ammonia, and
alkaline phosphatase levels21
Suspected rupture or perforation of the urinary
bladder as indicated by elevated ammonia, creatinine, and urea levels
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test will be performed by a physician and
takes approximately 30 minutes

Reference Values
Red blood cells

100,000/mm3

White blood cells

300/mm3 (undiluted peritoneal fluid)
500/mm3 (lavage fluid)

Neutrophils

25%

Absolute granulocyte count

250/mm3

Gram stain and culture

No organisms present

AFB smear and culture

No AFB present

Cytologic examination
Glucose
Amylase
Ammonia
Alkaline phosphatase
Creatinine
Urea
Carcinoembryonic antigen
Critical values

No abnormal cells present

Parallel serum levels

Positive Gram stain or culture

CHAPTER 9—Analysis

That there are no food or fluid restrictions before
the test
The positioning used for the procedure (seated or
in high-Fowler’s position)
That the skin will be injected with a local anesthetic at the abdominal needle insertion site
and that this injection may cause a stinging sensation
That, after the skin has been anesthetized, a large
needle will be inserted through the abdominal
wall
That a “popping” sensation may be experienced as
the needle penetrates the peritoneum
The importance of remaining still during the
procedure
Any activity restrictions after the test (usually 1
hour or more of bed rest)
Prepare for the procedure:
Withhold anticoagulant medications and aspirin
as ordered.
Have the client void, or catheterize the client if he
or she is unable to void to ensure an empty bladder that is not as likely to be punctured by the
needle.
Provide a hospital gown and have the client put it
on with the opening in the front.
Take and record vital signs.
If the client has ascites, obtain weight and measure abdominal girth.
If the abdomen is hirsute, it may be necessary to
shave the area of the puncture site.
THE PROCEDURE (PARACENTESIS)

The necessary equipment is assembled, including a
paracentesis tray with solution for skin preparation,
local anesthetic, 50-mL syringe, needles of various
sizes including large-bore paracentesis needle or
trocar and cannula, sterile drapes, and sterile gloves.
Specimen collection tubes and bottles for the tests to
be performed also are needed.
The client is assisted to the position that will be
used for the test. The usual position is sitting on the
side of a bed or treatment table, with the feet and
back supported. An alternative approach is to place
the client in bed in a high-Fowler’s position.
The skin is cleansed with an antiseptic solution
and protected with sterile drapes. The skin at the
needle or trocar insertion site is then infiltrated with
local anesthetic. The paracentesis needle is inserted
approximately 1 to 2 inches below the umbilicus. If
a trocar with cannula is to be used, a small skin incision may be made to facilitate insertion. The 50-mL
syringe with stopcock is attached to the needle or
cannula after the trocar has been removed. Gentle
suction may be applied with the syringe to remove

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291

fluid. For peritoneal lavage, sterile normal saline or
Ringer’s lactate may be infused via the needle or
cannula over 15 to 20 minutes. The client is then
turned from side to side before the lavage fluid is
removed.
Samples of peritoneal or ascitic fluid are obtained,
placed in appropriate containers, labeled, and sent
promptly to the laboratory. If the paracentesis is
being performed for therapeutic as well as diagnostic reasons, additional fluid is removed. No more
than 1000 to 1500 mL of fluid should be removed at
any one time to avoid complications such as hypovolemia and shock resulting from abdominal pressure changes and massive fluid shifts into the space
that has been drained by paracentesis.
When the desired amount of fluid has been
removed, the needle or cannula is withdrawn and
slight pressure is applied to the site for a few
minutes. If there is no evidence of bleeding or other
drainage, a sterile dressing is applied to the site.
NURSING CARE DURING THE PROCEDURE

If feasible, check the client’s vital signs every 15
minutes during the procedure.
Observe the client for pallor, diaphoresis, vertigo,
hypotension, tachycardia, pain, or anxiety. Rapid
removal of fluid may precipitate hypovolemia and
shock.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to a position of comfort and
reminding the client of any activity restrictions.
Redress the puncture site using sterile technique if
excessive drainage is present.
Take and record vital signs as for a postoperative
client (i.e., every 15 minutes for the first hour,
every 30 minutes for the next 2 hours, every hour
for the next 4 hours, and then every 4 hours for
24 hours). Take temperature every 4 hours for
24 hours. Monitor intake and output for at least
24 hours.
Assess the puncture site for bleeding, excessive
drainage, and signs of inflammation each time the
vital signs are taken and daily thereafter for several
days.
Continue to observe the client for pallor, vertigo,
hypotension, tachycardia, pain, or anxiety for at
least 24 hours after the procedure.
If a large amount of fluid was removed, measure
abdominal girth and weigh the client.
Provide support when diagnostic findings are
revealed and information is given about subsequent therapy (antibiotics) based on findings.
Have IV fluids and albumin on hand if hypoten-

292

SECTION I—Laboratory

Tests

sion results from the fluid shift from the vascular
space.
Note severe abdominal pain. Rigid abdominal
muscles indicate that peritonitis is developing
from the paracentesis.
Notify physician immediately of a positive Gram
stain or culture.

SYNOVIAL FLUID ANALYSIS
Synovial fluid is a clear, pale yellow, and viscous
liquid formed by plasma ultrafiltration and by secretion of a hyaluronate–protein complex by synovial
cells. It is secreted in small amounts (i.e., 3 mL or
less) into the cavities of most joints. Synovial effusions are associated with disorders or injuries involving the joints. Samples for analysis are obtained by
aspirating joint cavities. The most commonly aspirated joint is the knee, although samples can also be
obtained from the shoulder, hip, elbow, wrist, and
ankle if clinically indicated.
Synovial fluid analysis is used primarily to determine the type or cause of joint disorders. Joint disorders can be classified according to five categories
based on synovial fluid findings: (1) noninflammatory (e.g., degenerative joint disease), (2) inflammatory (e.g., rheumatoid arthritis, SLE), (3) septic (e.g.,
acute bacterial or tuberculous arthritis), (4) crystal
induced (e.g., gout or pseudogout), and (5) hemorrhagic (e.g., traumatic or hemophilic arthritis).22
Tests commonly performed on synovial fluid
include red cell count, white cell count and differential, white cell morphology, microscopic examination for crystals, Gram stain, and C&S. Determination of protein, glucose, and uric acid levels
also aids in diagnosis. Various immunologic tests
such as determination of complement, rheumatoid
factor, and antinuclear antibodies also have been
used in synovial fluid analysis. In the recent past, the
mucin clot test has been used in analyzing synovial
fluid, but this test is not considered as reliable as
specific cell counts and other measurements of
synovial fluid constituents. Lactate and pH measurements can be used as nonspecific indicators of
inflammation and to differentiate between infection
and inflammation.23
Table 9–2 lists the types of white blood cells and
inclusions seen in synovial fluid, along with the
disorders with which the presence of such cells is
associated.
Examination of synovial fluid for crystals is used
in diagnosing crystal-induced arthritis. The several
types of crystals that can be identified are listed in
Table 9–3. Monosodium urate (MSU) crystals are
associated with arthritis caused by gout, whereas

calcium pyrophosphate (CPP) crystals are seen in
pseudogout. Cholesterol crystals are associated with
chronic joint effusions, which may be caused by
tuberculous or rheumatoid arthritis. Arthritis associated with the presence of apatite crystals is
commonly recognized as a cause of synovitis.
Corticosteroid crystals may be seen for a month or
more after intra-articular injections of steroids and
may induce acute synovitis. Although usually of a
rhomboid shape, corticosteroid crystals are sometimes needle shaped and may be confused with MSU
or CPP crystals. Not shown in Table 9–3 are talcum
crystals. These crystals, which are shaped like
Maltese crosses, are most commonly seen after joint
surgery and reflect contamination of the joint with
talcum powder from surgical gloves.24
Gram stain and C&S tests are used to identify the
causative organisms when infection is suspected.
AFB smear and culture can be performed when
tuberculous arthritis is suspected, but results are
frequently negative. When the results of microbiologic tests of synovial fluid are inconclusive, synovial
biopsy may be necessary to establish the diagnosis.25
The need to perform immunologic tests of
synovial fluid is indicative of the association of the
immune system with inflammatory joint disorders.
Substances measured include rheumatoid factor
(RF), antinuclear antibodies (ANA), and complement, all of which can also be measured in serum
(see Chapter 3).
Determination of complement levels in synovial
fluid aids in differentiating arthritis of immunologic
origin from that with nonimmunologic causes.
Decreased synovial fluid complement levels are
seen in approximately 60 to 80 percent of individuals with rheumatoid arthritis and SLE. Decreased
complement levels are occasionally seen in rheumatic fever, gout, pseudogout, and bacterial arthritis; however, synovial complement levels may be
high in these disorders if serum levels also are
elevated. Complement levels in synovial fluid can be
measured as total complement (CH50) or as individual components (C1q, C4, C2, and C3). Because
synovial fluid complement levels parallel synovial
fluid protein levels, complement levels can be
expressed as ratios in relation to protein levels to
ensure that abnormal findings are not caused by
changes in synovial fluid membrane filtration.26,27
INTERFERING FACTORS

Blood in the sample caused by traumatic arthrocentesis
Undetected hypoglycemia or hyperglycemia or
failure to comply with dietary restrictions before
the test, or both

CHAPTER 9—Analysis

TABLE 9–2

•

of Effusions

293

White Blood Cells and Inclusions Seen in Synovial Fluid

Cell/Inclusion
Neutrophil

Description

Significance

Polymorphonuclear leukocyte

Bacterial sepsis
Crystal-induced inflammation

Lymphocyte

Mononuclear leukocyte

Nonseptic inflammation

Macrophage (monocyte)

Large mononuclear leukocyte; may be
vacuolated

Normal
Viral infections

Synovial lining cell

Similar to macrophage but may be multinucleated, resembling a mesothelial cell

Normal

LE cell

Neutrophil containing characteristic
ingested “round body”

Lupus erythematosus

Reiter cell

Vacuolated macrophage with ingested
neutrophils

Reiter’s syndrome
Nonspecific inflammation

RA cell (ragocyte)

Neutrophil with dark cytoplasmic granules
containing immune complexes

Rheumatoid arthritis
Immunologic inflammation

Cartilage cells

Large, multinucleated cells

Osteoarthritis

Rice bodies

Macroscopically resemble polished rice

Tuberculosis, septic and
rheumatoid arthritis

Microscopically show collagen and fibrin
Fat droplets

Refractile intracellular and extracellular
globules

Traumatic injury

Stain with Sudan dyes
Hemosiderin

Inclusions within synovial cells

Pigmented villonodular
synovitis

From Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis, 2001, p 182, with permission.

TABLE 9–3

•

Synovial Fluid Crystals

Crystal

Shape

Monosodium urate

Needles

Calcium pyrophosphate

Rods
Needles
Rhombics

Cholesterol

Notched rhombic plates

Apatite

Small needles

Corticosteroid

Flat, variable-shaped plates

Adapted from Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis, 2001, p 183.

294

SECTION I—Laboratory

Tests

Reference Values
Red blood cells

2000/mm3

White blood cells

200/mm3

Neutrophils

25%

White cell morphology

No abnormal cells or inclusions (see Table 9–2)

Crystals

None present (see Table 9–3)

Gram stain and culture

No organisms present

Acid-fast bacillus smear and culture

No AFB present

Protein

3 g/dL

Glucose

Not 10 mg/dL of blood level or not 40 mg/dL

Uric acid

Parallels serum level

Lactate

0.6–2.0 mmol/L or 5–20 mg/dL

Antinuclear antibodies
Rheumatoid factor
Complement

Critical values

Contamination of the sample with pathogens
Improper handling of the specimen (Refrigeration of the sample may result in an increase in
MSU crystals because of decreased solubility of
uric acid. Exposure of the sample to room air with
a resultant loss of carbon dioxide and rise in pH
encourages the formation of calcium CPP crystals.)28
INDICATIONS FOR SYNOVIAL FLUID ANALYSIS

Joint effusion of unknown etiology
Suspected trauma, tumors involving the joint, or
hemophilic arthritis as indicated by an elevated
red cell count, elevated protein level, and possibly
fat droplets if trauma is involved (see Table 9–2)
Suspected joint effusion caused by noninflammatory disorders (e.g., osteoarthritis, degenerative
joint disease) as indicated by a white cell count of
less than 5000 per cubic millimeter with a normal
differential and the presence of cartilage cells (see
Table 9–2)
Suspected rheumatoid arthritis as indicated by a
white cell count of 2,000 to 100,000 per cubic
millimeter with an elevated neutrophil count (i.e.,
30 to 50 percent), presence of rheumatoid arthritis cells and possibly rice bodies (see Table 9–2),
cholesterol crystals if effusion is chronic, elevated
protein level, decreased glucose level, moderately
elevated lactate level (i.e., 2 to 7.5 mmol/L),

Parallel serum levels
Positive Gram stain or culture

decreased pH, presence of RF (60 percent of
cases), and decreased complement
Suspected SLE involving the joints as indicated by
a white cell count of 2,000 to 100,000 per cubic
millimeter with an elevated neutrophil count (i.e.,
30 to 40 percent), presence of LE cells (see Table
9–2), elevated protein level, decreased glucose
level (i.e., 2 to 7.5 mmol/L), decreased pH, presence of ANA (20 percent of cases), and decreased
complement
Suspected acute bacterial arthritis as indicated by
a white cell count of 10,000 to 200,000 per cubic
millimeter with a markedly elevated neutrophil
count (i.e., as high as 90 percent), positive Gram
stain (50 percent of cases), positive cultures (30 to
80 percent of cases), possible presence of rice
bodies (see Table 9–2), decreased glucose, lactate
level greater than 7.5 mmol/L, pH less than 7.3,
and complement levels paralleling those found in
serum (i.e., may be elevated or decreased)29
Suspected tuberculous arthritis as indicated by a
white cell count of 2,000 to 100,000 per cubic
millimeter with an elevated neutrophil count (i.e.,
30 to 60 percent), possible presence of rice bodies
(see Table 9–2), cholesterol crystals if effusion is
chronic, positive AFB smear and culture in some
cases (results are frequently negative), decreased
glucose, elevated lactate levels, and decreased pH
Suspected joint effusion caused by gout as indi-

CHAPTER 9—Analysis

cated by a white cell count of 500 to 200,000 per
cubic millimeter with an elevated neutrophil
count (i.e., approximately 70 percent), presence of
MSU crystals (see Table 9–3), decreased glucose,
elevated uric acid levels, and complement levels
paralleling those of serum (may be elevated or
decreased)30,31
Differentiation of gout from pseudogout as indicated primarily by finding CPP crystals (see Table
9–3), which are associated with pseudogout
(Other findings in pseudogout are similar to those
of gout except that the white cell count may not be
as high.)
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That it will be performed by a physician and
requires approximately 20 minutes
Any dietary restrictions (fasting for 6 to 12 hours
before the test is recommended if the synovial
fluid is to be tested for glucose)
The positioning to be used (seated or supine for
knee, shoulder, elbow, wrist, or ankle aspiration;
supine for hip joint aspiration)
That the skin at the site will be injected with a
local anesthetic and that it may cause a stinging
sensation
That, after the skin has been anesthetized, a large
needle will be inserted into the joint capsule
That discomfort may be experienced as the joint
capsule is penetrated
The importance of remaining still during the
procedure
Any activity restrictions after the test (The client
usually is advised to avoid excessive use of the
joint for several days after the procedure to
prevent pain and swelling.)
That ice packs or analgesics or both may be
prescribed after the procedure to prevent swelling
and alleviate discomfort
Prepare for the procedure:
Withhold anticoagulant medications and aspirin
as ordered.
Ensure to the extent possible that any dietary
restrictions are followed.
Have the client void.
Provide a hospital gown if necessary to allow
access to the site without unduly exposing the
client.
Take and record vital signs.
If the client is extremely hirsute, it may be necessary to shave the area of the puncture site.
THE PROCEDURE (ARTHROCENTESIS)

The necessary equipment is assembled, including an

of Effusions

295

arthrocentesis tray with solution for skin preparation, local anesthetic, a 20-mL syringe, needles of
various sizes, sterile drapes, and sterile gloves.
Specimen collection tubes and containers for the
tests to be performed also are obtained. For cell
counts and differential, lavender-topped tubes
containing ethylenediaminetetra-acetic acid (EDTA)
are used. Green-topped tubes containing heparin are
used for certain immunologic and chemistry tests,
whereas samples for glucose are collected in either
plain red-topped tubes or gray-topped tubes
containing potassium oxalate. Plain sterile tubes
(e.g., red-topped tubes) are recommended for
microbiologic testing and crystal examination.32
The client is assisted to the position that will be
used for the test (sitting or supine). The skin is
cleansed with antiseptic solution, protected with
sterile drapes, and infiltrated with local anesthetic.
The aspirating needle is inserted into the joint space
and as much fluid as possible is withdrawn. The
specimen should contain at least 10 mL of synovial
fluid, but more may be removed to reduce swelling.
Manual pressure may be applied to facilitate fluid
removal.
If medication is to be injected into the joint, the
syringe containing the sample is detached from the
needle and replaced with the one containing the
drug. The medication is injected with gentle pressure. The needle is then withdrawn and digital pressure is applied to the site for a few minutes. If there
is no evidence of bleeding, a sterile dressing is
applied to the site. An elastic bandage may also be
applied to the joint.
The samples of synovial fluid are placed in the
appropriate containers, labeled, and sent to the laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to a position of comfort.
Apply an ice pack to the site and administer analgesics as needed.
Resume any foods, fluids, or medications withheld before the test on the physician’s order.
Remind the client of any activity restrictions and,
if indicated, site care requirements.
Apply an elastic bandage to the joint to provide
support and to minimize edema formation.
Take and record vital signs.
Assess comfort level and response to measures
such as ice packs and analgesics.
Assess the puncture site for bleeding, bruising,
inflammation, and excessive drainage of synovial
fluid approximately every 4 hours for 24 hours
and then daily thereafter for several days.

296

SECTION I—Laboratory

Tests

Provide support when diagnostic findings are
revealed and information is provided about
subsequent treatment based on findings (antiinflammatory drugs, immobilization of the joint,
analgesics).
Notify physician immediately of a positive Gram
stain or culture.
REFERENCES
1. Hole, JW: Human Anatomy and Physiology, ed 4. Wm C Brown,
Dubuque, Iowa, p 158.
2. Ibid, p 158.
3. Kjeldsberg, CR, and Krieg, AF: Cerebrospinal fluid and other body
fluids. In Henry, JB: Clinical Diagnosis and Management by
Laboratory Methods, ed 18. WB Saunders, Philadelphia, 1991, p
457.
4. Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis,
Philadelphia, 2001, p 191.
5. Kjeldsberg and Krieg, op cit, p 463.
6. Miller, BF, and Keane, CB: Encyclopedia and Dictionary of
Medicine, Nursing and Allied Health, ed 4. WB Saunders,
Philadelphia, 1987, p 226.
7. Kjeldsberg and Krieg, op cit, p 468.

8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.

Strasinger, op cit, p 173.
Kjeldsberg and Krieg, op cit, p 461.
Ibid, p 458.
Strasinger, op cit, p 182.
Ibid, p 182.
Ibid, p 180.
Ibid, p 182.
Kjeldsberg and Krieg, op cit, p 464.
Strasinger, op cit, p. 183.
Kjeldsberg and Krieg, op cit, p 465.
Ibid, p 469.
Ibid, p 468.
Strasinger, op cit, p 184.
Kjeldsberg and Krieg, op cit, p 469.
Strasinger, op cit, pp 172–173.
Kjeldsberg and Krieg, op cit, pp 461–462.
Ibid, pp 459–460.
Ibid, pp 462–463.
Ibid, p 462.
Strasinger, op cit, p 178.
Ibid, p 174.
Ibid, p 177.
Ibid, p 174.
Kjeldsberg and Krieg, op cit, p 462.
Strasinger, op cit, p 172.

CHAPTER

Amniotic Fluid Analysis
TESTS COVERED
Tests for Genetic and Neural Tube
Defects, 298

Tests for Hemolytic Disease of the
Newborn, 299
Tests for Fetal Maturity, 300

OVERVIEW OF AMNIOTIC FLUID FORMATION AND ANALYSIS

Amniotic fluid
is produced in the membranous sac that surrounds the developing fetus. This sac appears
during the second week of gestation and arises from a membrane called the amnion. Amniotic
fluid is derived from the exchange of water from maternal blood across fetal membranes, from
fetal cellular metabolism, and later in pregnancy from fetal urine. Amniotic fluid serves several
purposes. It prevents the amniotic membranes from adhering to the embryo and protects the
fetus from shocks and blows. It also aids in controlling the embryo’s body temperature and
permits the fetus to move freely, thus aiding in normal growth and development.1 Amniotic
fluid can be thought of as an extension of the extracellular fluid space of the fetus.2 Testing
samples of amniotic fluid for various constituents and substances can, therefore, be used to
assess fetal well-being and maturation. Specifically, amniotic fluid analysis is used to test for
various inherited disorders, anatomic abnormalities such as neural tube defects, hemolytic
disease of the newborn, and fetal maturity.
Amniotic fluid is normally clear and colorless in early pregnancy. Later in pregnancy, it may
appear slightly opalescent because of the presence of particles of vernix caseosa and may be pale
yellow because of fetal urine. The presence of meconium in amniotic fluid is normal in breech
presentations but abnormal in vertex presentations and indicates relaxation of the anal sphincter from hypoxia. Amniotic fluid stained the color of port wine generally indicates abruptio
placentae.
As the fetus begins to produce urine, it also swallows amniotic fluid in amounts that nearly
equal urinary output (i.e., 400 to 500 mL per day).3 Failure to swallow sufficient amounts of
amniotic fluid results in excessive accumulation of fluid in the amniotic sac (polyhydramnios).
This occurrence is commonly associated with anencephaly and esophageal atresia but can also
occur in the presence of maternal diabetes and hypertensive disorders of pregnancy. Excessive
amounts of amniotic fluid also are seen with fetal edema, which is associated with fetal heart
failure, hydrops fetalis, and multiple births. Excessive swallowing of amniotic fluid results in
decreased volume (oligohydramnios) and is associated with chronic illness of the fetus, placental insufficiency, fetal urinary tract malformations, and multiple births.4 By the 14th to 16th
weeks of pregnancy, the amniotic sac normally contains at least 50 mL of fluid; at term, the sac
contains 500 to 2500 mL of amniotic fluid, with an average volume of 1000 mL.
Samples of amniotic fluid are obtained by needle aspiration (Fig. 10–1). As noted in Chapter
9, centesis is a suffix denoting “puncture and aspiration of ”; thus, aspiration of fluid from the
amniotic sac is called amniocentesis. For suspected genetic and neural tube defects, amniocen297

298

SECTION I—Laboratory

Tests

tesis is generally performed early in the
second trimester of pregnancy (i.e., 14th to
16th weeks), when there is sufficient amniotic fluid for sampling yet enough time for
safe abortion, if desired. For hemolytic

Figure 10–1.

disease of the newborn, a series of amniocenteses may be performed beginning with the
26th week. Tests for fetal maturity usually are
not performed until at least the 35th week of
gestation.

Amniocentesis with needle placement to obtain an amniotic fluid sample.

TESTS OF AMNIOTIC FLUID
Tests of amniotic fluid are discussed hereafter in
relation to the three general purposes for which they
are performed: (1) to detect genetic and neural tube
defects, (2) to test for hemolytic disease of the
newborn, and (3) to assess fetal maturity.

TESTS FOR GENETIC AND NEURAL
TUBE DEFECTS
Tests for genetic and neural tube defects include
gender determination, chromosome analysis, and
measurement of -fetoprotein (AFP) and acetylcholinesterase levels. Determination of the gender
of the fetus is indicated when sex-linked inherited
disorders are suspected (e.g., hemophilia, Duchenne’s muscular dystrophy). In such disorders, the
abnormal gene is carried by women, although the
disorder itself is inherited only by male offspring.
Although no specific tests for these disorders are
currently available, knowing the gender of the fetus
may aid in deciding whether to continue the preg-

nancy. Some couples carrying these disorders, for
example, choose to abort all male fetuses, even
though some would have been normal.5
Determining the chromosomal makeup (karyotype) of the fetus may also assist in the prenatal
diagnosis of disorders such as Down syndrome
(trisomy 21) and Tay-Sachs disease. Karyotyping,
especially when augmented by staining techniques,
includes determination of the number of chromosomes as well as specific morphologic changes in the
chromosomes that may indicate various genetic
disorders. Karyotyping is performed by culturing
fetal cells and then photographing individual chromosomes during the metaphase of mitosis.6 Among
the disorders that can be detected are alterations in
carbohydrate, lipid, and amino acid metabolism.
Karyotyping can take from 2 to 4 weeks before
results are available to the client. Specimens for
chromosome analysis must be delivered promptly to
the laboratory performing the test. If immediate
culturing is not possible, the sample must be incubated at normal body temperature for no longer
than 2 days.7

CHAPTER 10—Amniotic

Neural tube and other anatomic defects in the
fetus can be determined by measuring levels of AFP
and acetylcholinesterase in amniotic fluid. In the
embryo, the central nervous system develops from
the neural tube, which begins to form at about 22
days of gestation. Failure of the neural tube to close
properly can result in disorders such as anencephaly,
spina bifida, and myelomeningocele. During gestation, the major fetal serum protein is AFP. Similar to
albumin, this protein is manufactured in large
quantities by the fetal liver until the 32nd week
of gestation, with peak production occurring at 13
weeks (see Chapter 3). With a severe neural tube
defect, higher than normal amounts of AFP escape
into the amniotic fluid as well as into the maternal
circulation. Routine prenatal screening includes
determination of the mother’s serum AFP level at 13
to 16 weeks of pregnancy. Causes of elevated maternal AFP levels are listed in Table 10–1. If maternal
levels are elevated on two samples obtained 1 week
apart, an ultrasound is performed to determine
gestational age and to check for twins or gross fetal
anomalies.
If the ultrasound is normal, amniotic fluid
samples are obtained and analyzed for AFP levels.8,9
If AFP levels are elevated in amniotic fluid, the presence of acetylcholinesterase in the fluid can be
determined to confirm the presence of a neural tube
defect. Using electrophoretic methods, the isoenzyme of acetylcholinesterase, which originates in
fetal spinal fluid, can also be demonstrated and is
more specific to the diagnosis of neural tube
defect.10
AFP and acetylcholinesterase may be falsely

Fluid Analysis

299

elevated if the sample is contaminated with fetal
blood. The level of the fetal spinal fluid isoenzyme of
acetylcholinesterase is not, however, so affected.

TESTS FOR HEMOLYTIC DISEASE OF
THE NEWBORN
One of the oldest uses of amniotic fluid analysis is in
evaluating suspected hemolytic disease of the
newborn, in which the mother builds antibodies
against fetal red blood cell antigens (isoimmunization). The result is hemolysis of fetal erythrocytes
with release of bilirubin into the amniotic fluid. The
most common causes are ABO and Rh incompatibilities (e.g., an Rh-negative mother carrying an Rhpositive fetus), although other red cell antibodies
may also be involved. Maternal IgG antibodies may
cross the placenta to react with fetal red blood cells
as early as the 16th week of pregnancy. As fetal red
blood cells are broken down, bilirubin is released
and can be detected in the amniotic fluid.11
Normally, the bilirubin level in amniotic fluid is
highest between the 16th and 30th weeks of gestation. Much of this bilirubin is in the unconjugated
form and can be excreted by the placenta. As the fetal
liver matures, it begins to conjugate the bilirubin;
this can occur as early as 28 weeks of gestation. The
conjugated bilirubin is not, however, cleared by the
placenta; instead, it is excreted by the fetal biliary
tract and absorbed by the intestine. After the 30th
week of gestation, the bilirubin level in amniotic
fluid normally decreases as pregnancy progresses.
This is partly because of dilution of any bilirubin
present by the normal increase in amniotic fluid

Image/Text rights unavailable

300

SECTION I—Laboratory

Tests

volume. At term, bilirubin is nearly absent from
amniotic fluid.12
In hemolytic disease of the newborn, fetal red cell
destruction leads to excessive bilirubin levels, which
overwhelm both placental and fetal liver mechanisms for its clearance. Bilirubin levels in amniotic
fluid continue to rise throughout the pregnancy and
consist primarily of unconjugated bilirubin.13 The
amount of bilirubin present in the amniotic fluid
indicates the degree of fetal red hemolysis and, indirectly, the degree of fetal anemia.
When hemolytic disease of the newborn is
suspected or if maternal IgG levels are elevated, or
both, serial amniocenteses for bilirubin determinations are performed beginning at approximately the
26th week of pregnancy. Bilirubin measurement in
amniotic fluid is performed by spectrophotometric
analysis, with the optical density (OD) of the fluid
measured at wavelength intervals between 365 and
550 mm. When excessive bilirubin is present, a rise
in OD at 450 mm, the wavelength of maximum
bilirubin absorption, is seen.14 The results of spectrophotometric analysis can be compared with the
Liley graph (Fig. 10–2) to predict fetal outcome or to
plan medical management of the problem.
Substances other than bilirubin may cause
abnormal spectrophotometric results. Maternal

hemoglobin from a traumatic amniocentesis,
methemalbumin, and meconium in amniotic fluid
may cause false elevations, as will fetal acidosis. Fetal
hemoglobin can be differentiated from maternal
hemoglobin by staining and cytologic techniques.
The presence of methemalbumin indicates marked
hemolysis and impending fetal demise.15 Falsely
decreased bilirubin levels can occur if the amniotic
fluid sample is exposed to light or if excessive amniotic fluid volume causes dilution. Other disorders
that can cause elevated amniotic fluid bilirubin
levels include anencephaly and intestinal obstruction.16

TESTS FOR FETAL MATURITY
Tests for fetal maturity are generally performed after
the 35th week of pregnancy, when preterm delivery
is being considered because of fetal or maternal
problems. The lungs are the last of the fetal organs to
mature; therefore, the most common complication
of early delivery is newborn respiratory distress
syndrome (RDS). Tests of amniotic fluid for fetal
maturity focus on determining fetal lung maturity
and include the lecithin:sphingomyelin (L:S) ratio,
as well as measures of other lung surface lipids such
as phosphatidylglycerol and phosphatidylinositol.

Image/Text rights unavailable

CHAPTER 10—Amniotic

If the lungs are found to be mature by these tests,
the other body organs also are assumed to be
mature.17,18 Tests of amniotic fluid, which can be
used to indicate maturity of other fetal organ
systems, include creatinine and bilirubin determinations, as well as examination of fetal cells for type
and lipid content.
During the last trimester of pregnancy, fetal lung
enzyme systems initiate the production of surfactant
by type II pneumocytes, which line the alveoli.
Surfactant, a phospholipid mixture, lowers the
surface tension in the alveoli and prevents them
from collapsing during exhalation. The phospholipid components of surfactant are (1) lecithin
(phosphatidylcholine), (2) sphingomyelin, (3) phosphatidyl glycerol (PG), (4) phosphatidylethanolamine (PE), (5) phosphatidylinositol (PI), and (6)
phosphatidylserine (PS). Surfactant appears in
amniotic fluid as a result of fetal respiratory movements that cause it to diffuse from fetal airways.19
L:S RATIO

Lecithin constitutes about 75 percent of surfactant
in mature lungs and is responsible for most of the
surface activity of surfactant. The saturated form of
lecithin, -palmitic -myristic lecithin, is seen early
in the third trimester; the desaturated form,
dipalmitic lecithin (L), begins to appear at approximately 35 weeks’ gestation and continues to increase
throughout the remainder of the pregnancy.
Sphingomyelin, a surfactant component without
major surface activity properties, remains fairly
constant during pregnancy. The L:S ratio measures
the relationship between lecithin and sphingomyelin; if the increasing amount of lecithin over
the relatively constant amount of sphingomyelin
produces a ratio of 2:1 or more, fetal lung maturity
is generally indicated, as long as the pregnancy is
uncomplicated and the amniotic fluid sample is not
contaminated with blood or meconium.20
PHOSPHATIDYL GLYCEROL

A more reliable measure of fetal lung maturity is the
“lung profile,” in which the concentrations of the
several lung surface lipids (i.e., PG, PI, PS, and PE)
are measured in addition to lecithin and sphingomyelin. Next to lecithin, PG is the second major
constituent of surfactant and is believed to aid in
maintaining alveolar stability. PG appears in amniotic fluid at about 36 weeks’ gestation and indicates
secretion of mature surfactant. It has been found
that, if PG is present in amniotic fluid, RDS in the
newborn will not occur. PI is found in amniotic fluid
before the appearance of PG and indicates immature
fetal lungs. PI has a peak concentration at approxi-

Fluid Analysis

301

mately 5 weeks before term and decreases thereafter.
Measurement of PG and PI are most useful because
they are unaffected by the presence of blood and
meconium, although PG is affected by dilution of
the specimen with water and by variations in test
performance techniques. In addition to their usefulness in evaluating bloody or meconium-stained
samples of amniotic fluid, lung profiles aid in determining lung maturity in fetuses of diabetic mothers.
In maternal diabetes, the L:S ratio may indicate fetal
lung maturity even though PG is not present. If the
infant were delivered, RDS would be likely to occur.
Measurement of PG in such situations aids in determining whether delivery should be attempted.21,22
The significance of measures of PS and PE in lung
profiles has not yet been determined.
SHAKE TEST

A bedside test to estimate fetal lung maturity can be
performed when immediate results are needed. The
shake test is based on the ability of surfactant to
form stable foam, even in the presence of alcohol,
which impairs foaming of most other biologic
compounds. In this test, equal amounts of 95
percent ethanol and amniotic fluid are shaken
together vigorously for 15 seconds and then allowed
to stand undisturbed for 15 minutes. If a complete
ring of bubbles is present at the meniscus, the test
result is reported as positive, which indicates that
sufficient lecithin is available for fetal lung maturity.23 The sample of amniotic fluid for the shake test
can also be diluted with saline to various concentrations to estimate fetal lung maturity more accurately. The test result should be positive even when
amniotic fluid has been diluted with two parts of
saline.24
CREATININE BILIRUBIN

Other tests of amniotic fluid for fetal maturity
include creatinine and bilirubin determinations and
examination of fetal cells for type and lipid content.
Creatinine appears in increased amounts in amniotic fluid at about the 36th week of gestation because
of urinary excretion by the fetal kidneys and
increased fetal muscle mass. A creatinine concentration of greater than 2.0 mg/dL indicates a fetal age of
at least 36 to 37 weeks.25,26 As noted previously,
bilirubin levels decline throughout the last several
weeks of pregnancy. Thus, a bilirubin level of less
than 0.025 mg/dL at term is considered an indication of fetal maturity. Note, however, that bilirubin
levels cannot be used to assess fetal maturity in
isoimmunized mothers, because levels will be
elevated as a result of hemolytic disease involving
the fetus.

302

SECTION I—Laboratory

Tests

During the second and third trimesters, fetal
epithelial cells are shed into the amniotic fluid. As
the fetus matures, the percentage of cells containing
lipids increases. The test is performed by staining the
cells with Nile blue stain. Cells containing lipid
appear orange.27 Although only 1 percent of the cells
contain lipid at 34 weeks’ gestation, 10 to 50 percent
contain lipid at 38 to 40 weeks.28 Fetal maturity may
also be evaluated by examining the types of cells
present. Whereas basal cells are present until about
32 weeks’ gestation, cornified cells appear at 36
weeks and are the predominant cell type after 38
weeks.29

exposed to light or if amniotic fluid volume is
excessive.
Contamination of the sample with blood or
meconium may yield inaccurate L:S ratios.
INDICATIONS FOR AMNIOTIC FLUID TESTS

INTERFERING FACTORS

Failure to promptly deliver samples for chromosomal analysis to the laboratory performing the
test or improper incubation of the sample, or
both, such that cells do not remain alive, makes
karyotyping impossible to perform. Sample
should also be protected from light.
AFP and acetylcholinesterase may be falsely
elevated if the sample is contaminated with fetal
blood.
Bilirubin may be falsely elevated if maternal
hemoglobin, methemalbumin, or meconium are
present in the sample. Fetal acidosis may also lead
to falsely elevated bilirubin levels.
Bilirubin may be falsely decreased if the sample is

Familial or parental history of genetic disorders
such as Tay-Sachs disease, mental retardation,
chromosome or enzyme anomalies, or inherited
hemoglobinopathies
Advanced maternal age (Chromosomal analysis is
routine in mothers age 35 years or older.)
Prenatal gender determination when the mother
is a known carrier of a sex-linked abnormal gene
that could be transmitted to male offspring
In utero diagnosis of metabolic disorders such as
cystic fibrosis, diabetes mellitus, or other errors of
lipid, carbohydrate, or amino acid metabolism
Suspected neural tube defect as indicated by
elevated AFP and acetylcholinesterase levels
Known or suspected hemolytic disease involving
the fetus as indicated by rising bilirubin levels,
especially after the 30th week of gestation
Determination of fetal maturity when preterm
delivery is being considered, with fetal maturity
indicated by a L:S ratio of 2:1 or greater, presence
of PG, positive shake test, creatinine greater than
2.0 mg/dL, and bilirubin less than 0.025 mg/dL
(nonisoimmunized mother)

Reference Values
Conventional Units

SI Units

Color

Light straw or colorless

Chromosome analysis

Normal karyotype

-Fetoprotein

13–41 g/mL at 13–14 wk

1–4 g/L

0.2–3.0 g/mL at term

0.02–0.03 g/L at term

Acetylcholinesterase

Absent

Bilirubin

0.075 mg/dL early in pregnancy

1.28 mol/L

0.025 mg/dL at term

0.43 mol/L

L:S ratio

1.6:1 before 35 wk
2.0:1 at term

Phosphatidylglycerol

Present at approximately 36 wk

Phosphatidylinositol

Peak amounts present 5 wk before
term, followed by a decline

Shake test

Positive

Creatinine

1.8–4.0 mg/dL at term

159–354 mol/L

CHAPTER 10—Amniotic

CONTRAINDICATIONS

History of premature labor or incompetent cervix
Presence of placenta previa or abruptio placentae
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician and requires 20 to 30 minutes
The precautions taken to avoid injury to the fetus
(i.e., careful palpation, localization of the fetus
and placenta by ultrasound, and use of strict aseptic technique)
The positioning used for the procedure and the
necessity of remaining still while it is taking place
That the skin will be injected with a local anesthetic at the needle insertion site and that this
injection may cause a stinging sensation
That a sensation of pressure may be felt when the
needle is inserted for the amniotic fluid sample
How to use focusing and controlled breathing for
relaxation during the procedure
That slight cramping may occur after the procedure
That, if the test is being conducted for chromosomal studies, it may be 2 to 4 weeks before results
are available
Prepare for the procedure:
If an ultrasound is to be performed immediately
before the amniocentesis to localize the fetus and
placenta, hydrate the client to ensure a full bladder.
After the ultrasound, have the client empty the
bladder to prevent perforation during the amniocentesis. (The most common nonamniotic fluid
obtained during the procedure is maternal
urine.30)
Provide a hospital gown.
Record maternal vital signs and fetal heart rate.
THE PROCEDURE (AMNIOCENTESIS)

The necessary equipment is assembled, including an
amniocentesis tray with solution for skin preparation, local anesthetic, 10- or 20-mL syringe, needles
of various sizes (including a 22-gauge, 5-inch spinal
needle), sterile drapes, and sterile gloves. Special
specimen collection tubes (either brown or foilcovered) also are needed.
The client is assisted to a supine position. The
head or legs may be raised slightly to promote client
comfort and to relax abdominal muscles. If the
uterus is large, a pillow or rolled blanket is placed
under the client’s right side to prevent hypotension
resulting from great vessel compression.
The skin of the lower abdomen is prepared with
an antiseptic solution and protected with sterile

Fluid Analysis

303

drapes. The local anesthetic is injected. A 5-inch, 22gauge spinal needle is inserted, usually at the
midline, through the abdominal and uterine walls.
The stylet is withdrawn and a plastic syringe of sufficient volume for the sample to be obtained is
attached. A sample of at least 10 mL of amniotic
fluid is withdrawn and placed in appropriate
containers.
When the desired amount of fluid has been
removed, the needle is withdrawn and slight pressure applied to the site. If there is no evidence of
bleeding or other drainage, a sterile adhesive bandage is applied to the site. The specimens should be
sent to the laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to a position of comfort.
If the client is Rh-negative, administer Rho (D)
immune globulin (RhoGAM) intramuscularly to
prevent potential sensitization to fetal blood.
Remind the client to report fever, leaking amniotic fluid, vaginal bleeding, or uterine contractions to her physician.
Changes in fetal activity—either an increase or a
decrease—should also be reported.
Take and record maternal vital signs and fetal
heart sounds every 15 minutes for 1/2 to 1 hour.
Assess the client for contractions, pain, and vaginal bleeding each time vital signs are checked.
Observe the puncture site for bleeding or other
drainage.
Notify the physician if client experiences abdominal pain, fever, chills, vaginal bleeding, or change
in fetal activity.
Provide support when diagnostic findings are
revealed, especially if fetal abnormality is determined.
If appropriate and timely, offer information about
genetic counseling or pregnancy termination
counseling, or both.
REFERENCES
1. Moore, ML: Realities in Childbearing, ed 2. WB Saunders,
Philadelphia, 1983, p 762.
2. Wenk, RE, and Rosenbaum, JM: Analyses of amniotic fluid. In
Henry, JB: Clinical Diagnosis and Management by Laboratory
Methods, ed 18. WB Saunders, Philadelphia, 1991, p 482.
3. Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis,
Philadelphia, 2001, p 198.
4. Wenk and Rosenbaum, op cit, p 482.
5. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
1991, p 656.
6. Ibid, p 655.
7. Strasinger, op cit, p 199.
8. Wenk and Rosenbaum, op cit, pp 483–484.
9. Sacher and McPherson, op cit, p 626.
10. Wenk and Rosenbaum, op cit, p 484.
11. Ibid, p 485.

304
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.

SECTION I—Laboratory

Tests

Ibid, p 485.
Ibid, p 485.
Strasinger, op cit, p 200.
Wenk and Rosenbaum, op cit, pp 488–489.
Fischbach, FT: A Manual of Laboratory Diagnostic Tests, ed. 4. JB
Lippincott, Philadelphia, 1992, p 946.
Wenk and Rosenbaum, op cit, p 490.
Strasinger, op cit, p 200.
Wenk and Rosenbaum, op cit, p 490.
Ibid, pp 490–492.
Ibid, p 492.

22.
23.
24.
25.
26.
27.

Strasinger, op cit, pp 200–201.
Wenk and Rosenbaum, op cit, p 491.
Moore, op cit, p 430.
Strasinger, op cit, p 201.
Moore, op cit, p 430.
Pagana, KD, and Pagana, TJ: Diagnostic Testing and Nursing
Implications: A Case Study Approach, ed 2. CV Mosby, St Louis,
1986, p 175.
28. Moore, op cit, p 430.
29. Ibid, p 430.
30. Wenk and Rosenbaum, op cit, p 489.

CHAPTER

Semen Analysis
TESTS COVERED
Tests for Fertility, 306

Tests for the Presence of Semen, 308

OVERVIEW OF SEMEN FORMATION AND ANALYSIS Semen is a fluid that consists
of sperm suspended in seminal plasma. It is composed of four main fractions that are
contributed by (1) the testis and epididymis, (2) the seminal vesicle, (3) the prostate gland, and
(4) the bulbourethral and urethral glands (Fig. 11–1). Sperm, which are less than 5 percent of
the volume of semen, are produced in the testis and mature in the epididymis. The epididymis
is thought to secrete a number of proteins that are essential to the fertilizing capability of sperm.
Most mature sperm are stored in the vas deferens until released by emission and ejaculation.
While in the vas deferens, sperm are relatively inactive because of the diminished oxygen supply
and acid environments; they can, however, survive for up to 1 month in this location.1,2
The seminal vesicles, which contribute approximately 60 percent to the volume of semen, are
attached to the vas deferens near the base of the urinary bladder. They secrete a viscous, slightly
alkaline fluid with high levels of fructose, flavin, potassium, and citric acid. Fructose provides

Figure 11–1. Diagram of male genitalia. (From Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis,
Philadelphia, 2001, p. 170, with permission.)
305

306

SECTION I—Laboratory

Tests

the major nutrient for sperm after emission. (Sperm can survive in the vagina for more than 72
hours after sexual intercourse.3) Flavin is responsible for the fluorescence of semen in ultraviolet light, thus allowing detection of semen on clothing or other fabrics in rape cases. The
significance of the high potassium and citric acid levels in seminal fluid has not yet been established. The fluid secreted by the seminal vesicles also contains prostaglandins, which are
thought to stimulate muscular contractions in female reproductive organs, and a fibrinogenlike substance that causes semen to coagulate after ejaculation.4,5
The prostate gland, which contributes about 20 percent to the volume of semen, secretes a
milky fluid with a pH of 6.5, due largely to its high citric acid content. Prostatic fluid also is high
in proteolytic enzymes and acid phosphatase. The proteolytic enzymes are believed to act on
seminal fluid, causing coagulation and, subsequently, liquefaction of the ejaculate.6,7 The
bulbourethral and urethral glands secrete a clear, mucuslike fluid that cleanses the urethra and
lubricates the end of the penis in preparation for intercourse. This fluid contributes less than
10 to 15 percent to the volume of semen.8,9
When ejaculation occurs, the components of semen enter the urethra individually but in
rapid succession. Secretion from the bulbourethral and urethral glands occurs first, followed by
prostatic secretion and most of the sperm. Note that the first two components contribute only
about 40 percent of the total ejaculate. Finally, the seminal vesicles empty, contributing the bulk
of the fluid. The sequence in which these fluids appear is an important consideration in the
method of specimen collection for semen analysis. If, for example, coitus interruptus is practiced, it is possible that the sperm-rich portion will be missed and that the sample will consist
primarily of fluid from the seminal vesicles.10
Freshly ejaculated semen is viscous, opaque, and white or grayish white. It coagulates almost
immediately but within 10 to 30 minutes liquefies to become a translucent fluid that pours in
droplets and does not appear clumped or stringy. The pH of semen is slightly alkaline (average
7.7). A pH of less than 7.0 is indicative of a sample consisting mainly of prostatic secretions and
may indicate congenital aplasia of the seminal vesicles. Increased turbidity after liquefaction
may indicate the presence of leukocytes and inflammation. Blood in the sample is abnormal.
The usual volume of the ejaculate is 2 to 5 mL, although the amount may range from 0.7 to 6.5
mL and still be considered normal. Extending the time between ejaculations does not lead to
an increase in volume. Increased volumes of sperm-poor semen are associated with male infertility, whereas greatly decreased volumes may impair penetration of the cervical mucus by those
sperm present.11,12
Semen is examined in the laboratory for four main reasons: (1) to investigate infertility, (2)
to evaluate the effectiveness of vasectomy, (3) to support or disprove sterility in a paternity suit,
and (4) to investigate alleged or suspected rape. For fertility studies, the optimal method of
obtaining a specimen is masturbation, with collection of the ejaculate in a clean glass or plastic container. Other approaches include obtaining the specimen by coitus interruptus and
collection of the sample by using a condom. The problems associated with collecting the specimen by coitus interruptus have been noted previously. The use of condoms presents problems
because many of them contain spermicides. If used, the condom should be thoroughly washed
and dried first.
When rape is alleged or suspected, the specimen can be swabbed from the vagina with a
Papanicolaou stick or cotton-tipped applicator or can be obtained by aspiration with a bulb
syringe to which a rubber catheter is attached, or with saline lavage. Samples of dried semen on
the skin can be obtained by sponging the site with saline-moistened gauze. Sections of clothing
and other fabric samples containing semen can be soaked in saline for 1 hour. The resulting
solution is then subjected to semen analysis.13,14

TESTS OF SEMEN

TESTS FOR FERTILITY

Tests of semen are discussed in relation to those used
to determine fertility and those used when rape is
suspected.

In addition to examining the sample for appearance,
viscosity, and pH, fertility tests include assessment of
sperm count, sperm motility, and sperm morphol-

CHAPTER 11—Semen

Analysis

307

Figure 11–2.
Abnormal sperm morphology. (From Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis,
Philadelphia, 2001, p. 174, with permission.)

ogy. Other tests include determination of the viability of sperm, presence of fructose in the sample,
presence of antibodies to sperm, and ability of
sperm to penetrate the cervical mucus after coitus.
The sperm count is performed in a manner similar to that used for blood counts. With the liquefied
specimen diluted to immobilize the sperm, the
number of sperm in a given microscopic area is
counted and the result multiplied by a factor of
either 100,000 or 1 million to obtain the sperm
count. The normal sperm count ranges from 40 to
160 million per milliliter, with counts of 20 to 40
million per milliliter considered borderline normal.
For postvasectomy tests, only the sperm count is
necessary. It should eventually be negative for sperm
on two consecutive monthly examinations.
Because sperm must migrate through the cervical
mucus and the fallopian tubes, sperm motility is a
key indicator of fertility. For this test, the motility of
at least 200 sperm is examined microscopically. The
percentage of sperm showing progressive forward
motion is recorded and should normally be greater

Image/Text rights unavailable

than 60 percent within 3 hours of collecting the
sample. Those sperm showing progressive motility
can also be graded according to the quality of the
movement observed (Table 11–1).15
Sperm morphology involves microscopic examination of sperm to detect abnormal forms and
shapes that may render the sperm incapable of fertilization. The appearance of both the head and the tail
of a minimum of 200 sperm is evaluated. Normally,
the sperm has an oval head, which measures about
335 mm, and a long, tapering tail.16 Abnormal head
structures (Fig. 11–2) are associated with failure to
penetrate the ovum. Abnormal tail structures are
associated with poor sperm motility. The finding of
numerous immature sperm (spermatids) is also
considered abnormal because sperm usually mature
in the epididymis. In a normal specimen, fewer than
30 percent abnormal sperm will be found.17
If abnormalities in sperm count, motility, or
morphology are detected, additional tests can be
performed. Tests for sperm viability are indicated
when the sperm count is normal but motility
markedly decreased. Sperm viability is tested by
staining the sample such that dead and living sperm
appear different on microscopic examination.18 If
the sperm count is low, the sample may be examined
for the presence of fructose. As noted previously, the
fluid secreted by the seminal vesicles is high in fructose, a major nutrient for sperm. Thus, presence of
fructose in the sample indicates that adequate
support medium is available for the sperm and also
that the ejaculatory ducts are patent.19,20
Both men and women may produce antibodies to
sperm. Male antibodies are suspected when semen
analysis shows decreased sperm motility with
clumping. Female antibodies are suspected when

308

SECTION I—Laboratory

Tests

semen analysis is normal and assessment of the
woman reveals no cause for continuing infertility.
The test is performed by mixing sperm with serum
from either the man or the woman and then observing for agglutination or immobilization of the
sperm. The quantity of antibodies present can be
determined through radioimmunoassay techniques.21
Postcoital tests of semen are performed to determine both the quality of cervical mucus and the
ability of sperm to penetrate the cervical mucus and
still remain active. The test, known as the SimsHuhner test, is performed during the ovulatory
phase of the menstrual cycle, within 6 to 8 hours of
coitus. Normally, at least 10 motile sperm should be
present per high-power microscopic field. During
the ovulatory phase, cervical mucus should be clear
and somewhat watery with a spinnbarkeit of 10 cm.
A spinnbarkeit is a measure of tenacity of the cervical mucus and is determined by grasping a portion
of the cervical mucus with a forceps and seeing how
far it can be drawn before breaking.22,23
The sperm penetration assay assesses the qualitative aspects of sperm function. Oocytes from an
animal such as a hamster are used to determine the
ability of the sperm to penetrate the egg for possible
in vitro fertilization of a human egg.24

TESTS FOR THE PRESENCE OF SEMEN
Tests for the presence of semen are performed when
rape is alleged or suspected. These tests include
examination for sperm, determination of acid
phosphatase, and detection of blood group
substances.
As noted previously, the flavin content of semen is
responsible for the fluorescence of semen in ultraviolet light. Thus, a preliminary scan of the victim’s
clothing may help in identifying specific areas that
may yield samples for analysis. The presence of
sperm in samples obtained from clothing as well as
in vaginal secretions can be detected with various
staining techniques and by microscopic examination. Note, however, that sperm will not be detected
if the man has had a vasectomy or is sterile for some
other reason.
A more sensitive test to ascertain the presence of
semen is the acid phosphatase test, because semen is
the only body fluid high in this substance. The acid
phosphatase test specifically indicates the presence
of prostatic fluid and does not depend on the presence of sperm for a positive result. Vaginal samples
as well as clothing stains may be examined. Acid
phosphatase can be detected in semen stains that are
several months old.25

If the presence of semen is positively determined,
testing for the presence of A, B, or H blood group
substances can be used to ascertain whether the
semen sample is of the same or a different blood
group as that of the suspect. Inheritance of the H
gene is necessary for the normal expression of the
ABO genes and the subsequent development of A, B,
and H antigens and related blood groups. The H
gene is found in more than 99 percent of the population. Inheritance of the A gene leads to conversion
of nearly all of the H antigen on the red blood
cell surface to A antigen sites. Similarly, inheritance
of the B gene leads to conversion of H antigen to
B antigen sites. When both the A and B genes
are inherited, somewhat more H antigen sites
are changed to B than to A. Inheritance of the O
gene does not produce such changes in the H structure. Thus, blood group O has the highest level of
H antigen. In addition to their presence on red blood
cells, A, B, and H antigens are found on white blood
cells and platelets, and in all body secretions—
including semen—in 80 percent of the population.26,27
INTERFERING FACTORS

Improper specimen collection (e.g., use of
condoms containing spermicide, loss of spermrich portion of the sample through use of coitus
interruptus)
Failure to deliver the ejaculated sample to the
laboratory within 1 hour
Failure to maintain the ejaculated specimen at
body temperature until liquefaction occurs (20 to
60 minutes)
INDICATIONS FOR SEMEN ANALYSIS

Investigate infertility
Evaluate the effectiveness of vasectomy as indicated by two sperm-free samples collected 1
month apart
Support or disprove sterility in a paternity suit
Investigate alleged or suspected rape
NURSING CARE BEFORE THE PROCEDURE

Male Clients
Explain to the client:
The various procedures that may be used to
obtain the sample
The desirability of abstaining from sexual activity
for approximately 3 days before sample collection,
to promote the highest sperm count
The importance of transporting the sample
promptly to the laboratory, while maintaining it
at body temperature, if the sample is collected at
home

CHAPTER 11—Semen

Analysis

309

Reference Values
pH

7.0 (average 7.7)

Volume

0.7–6.5 mL/ejaculate (usually 1.5–5 mL)

Sperm count

40–160 million/mL (20–40 million/mL borderline normal)

Sperm motility

60% within 3 hr of specimen collection
Quality greater than grade II (see Table 11–1)

Sperm morphology

30% abnormal sperm

Fructose

Present and/or 150 mg/dL

Sperm antibodies

Negative for male and female antibodies

Postcoital test

At least 10 motile sperm per high-power microscopic field
within 6–8 hr of coitus

Acid phosphatase

2500 King-Armstrong U/mL (average)
SI units: 42 kat/L
Prostatic-enzymatic (SI units): 0.0–1.0 U/L
Prostatic-immunologic (SI units): 0.0–3.0 g/L

Prepare for the procedure:
Provide appropriate specimen collection containers.
Female Clients
Explain to the client:
That samples will be collected through vaginal
examination
That the use of lubricant during intercourse and
of douching after intercourse should be avoided
The positioning on the pelvic examination table
That, if saline lavage is used to collect the sample,
the client may experience a sensation of coldness
Prepare for the procedure:
The rape victim may need additional support to
cope with undergoing a vaginal examination.
Assist the client in donning an examination gown.
If rape is suspected, handle the client’s clothes
carefully because additional specimens may be
obtained from them.
Advise the client to void before the procedure.
Rape victims should not wipe after voiding, so as
not to remove possible semen.
THE PROCEDURE

Ejaculated Sample. The ideal sample is obtained in
the laboratory by masturbation and is collected in a
glass or plastic specimen container. If the sample is
collected at home by masturbation, it must be transported to the laboratory within 1 hour of collection
and must be maintained at body temperature.

If the client is unable to produce the specimen by
masturbation for either religious or psychological
reasons, the specimen may be obtained during the
sexual act through the use of condoms or coitus
interruptus. If a condom is used, it must be washed
and dried thoroughly before use to rid it of possible
spermicides. If coitus interruptus is used, the client
must be informed of the potential for loss of the
sperm-rich portion of the sample.
If none of the aforementioned approaches is
acceptable to the client, a final alternative is to
obtain postcoital samples from the cervical canal
and vagina of his partner.
Cervical/Vaginal Samples. The necessary equipment is assembled, including vaginal speculums,
Papanicolaou sticks, cotton-tipped applicators,
gloves, saline and syringes for lavage (if necessary), slides, and small jars containing 95 percent
ethanol.
The client is assisted to the lithotomy position on
the pelvic examination table. A vaginal speculum is
inserted and the specimen obtained by direct smear,
aspiration, or saline lavage. The specimens are
labeled and sent immediately to the laboratory.
Samples from Skin and Clothing. Samples of dried
semen on the skin can be obtained by sponging the
site with saline-moistened gauze. Sections of clothing and other fabric samples containing semen can
be soaked in saline for 1 hour. The resulting solution
is then subjected to semen analysis.

310

SECTION I—Laboratory

Tests

NURSING CARE AFTER THE PROCEDURE

There is no specific aftercare unless postejaculatory
or postcoital cleansing is desired.
Administer a spermicidal douche in addition to
the prescribed medication for prevention of pregnancy.
A supportive, nonjudgmental attitude can assist a
client through the experience of evaluation of
infertility or sexual function.
Grieving, loss of desired child: Offer counseling
for dealing with infertility. Assist client in developing coping strategies for feelings of inadequacy.
Anticipate client’s need to resolve grief and
express feelings. Offer information about support
groups and alternatives that can be explored.
REFERENCES
1. Cannon, DC: Seminal fluid. In Henry, JB: Clinical Diagnosis and
Management by Laboratory Methods, ed 18. WB Saunders,
Philadelphia, 1991, pp 497–498.
2. Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis,
Philadelphia, 2001, p 184.
3. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 701.

4. Cannon, op cit, pp 497–498.
5. Hole, JW: Human Anatomy and Physiology, ed 4. Wm C Brown,
Dubuque, Iowa, 1987, p 815.
6. Strasinger, op cit, p 184.
7. Cannon, op cit, p 498.
8. Hole, op cit, p 815.
9. Cannon, op cit, p 498.
10. Ibid, p 498.
11. Ibid, pp 498–499.
12. Strasinger, op cit, p 185.
13. Nurse’s Reference Library, op cit, p 701.
14. Cannon, op cit, p 502.
15. Ibid, pp 499–500.
16. Strasinger, op cit, p 187.
17. Ibid, pp 187–188.
18. Ibid, p 188.
19. Ibid, p 188.
20. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2001, p 641.
21. Strasinger, op cit, p 188.
22. Cannon, op cit, p 501.
23. Nurse’s Reference Library, op cit, pp 700, 703.
24. Sacher and McPherson, op cit, p 642.
25. Cannon, op cit, p 502.
26. Ibid, p 502.
27. Pittiglio, DH: Modern Blood Banking and Transfusion Practices.
FA Davis, Philadelphia, 1983, pp 94–96.

CHAPTER

Analysis of Gastric and
Duodenal Secretions
TESTS COVERED
Analysis of Gastric Contents, 312
Tests of Gastric Acidity, 315

Analysis of Duodenal Contents, 317
Duodenal Stimulation Tests, 319

OVERVIEW OF GASTRIC AND DUODENAL SECRETIONS

The stomach secretes
1500 to 3000 mL of gastric juice each day in response to ingestion of food; the sight, smell, or
thought of food; and excessive stress, alcohol, and caffeine. Normally, stomach secretions aid in
preparing ingested food for absorption in the small intestine, initiate the digestion of proteins,
and promote absorption of vitamin B12.
The chief cells of the stomach secrete digestive enzymes. The major enzyme secreted is
pepsinogen, which is converted to pepsin in the presence of hydrochloric acid. Hydrochloric
acid is secreted by the parietal cells of the stomach in a highly concentrated form with a pH of
approximately 0.8. Pepsin, which functions in the initial digestion of proteins, is most active in
an acidic environment. It functions optimally at a pH of 2.0 and a pH of not greater than 5.0.1
In addition to hydrochloric acid, the parietal cells secrete intrinsic factor, which aids in the
absorption of vitamin B12. The goblet cells and mucous glands of the stomach secrete a viscous
alkaline material that protects the stomach lining from damage by the acidic gastric juices.2
Gastric juices also contain other substances such as electrolytes (sodium, potassium, chloride,
and bicarbonate) and other enzymes such as gastric lipase, urease, lysozyme, and carbonic
anhydrase.3
Gastric juices are produced continuously, although amounts vary in relation to food intake
and other factors that stimulate or inhibit gastric secretion. The production of gastric juices is
normally lowest early in the morning. Gastric secretion is mediated by the autonomic nervous
system via the vagus nerve. When an individual ingests food—or thinks of, sees, or smells
food—parasympathetic impulses travel via the vagus nerve to the stomach and stimulate the G
cells of the stomach to secrete the hormone gastrin. Gastrin then stimulates the various cells in
the stomach to increase their secretions.4 In addition to distention of the stomach with food,
exposure of the gastric mucosa to substances called secretagogues also stimulates the secretion
of gastrin. Examples of such substances are alcohol, caffeine, meat extracts, and spices.
Because parasympathetic impulses increase gastric secretions, sympathetic nervous system
activity inhibits them. Gastric secretion, for example, is inhibited when food enters the small
intestine. This inhibition is thought to be caused by sympathetic impulses that are triggered
when acidic gastric contents come into contact with the upper part of the small intestine. These
sympathetic impulses ultimately inhibit those of the vagus nerve. Hormones secreted by the
small intestine also inhibit gastric secretion. These include enterogastrone, secretin, and cholecystokinin-pancreozymin (CCK-PZ).
311

312

SECTION I—Laboratory

Tests

In addition to the normal neural and humoral mechanisms involved in gastric secretion,
numerous other substances, including many drugs, can stimulate or inhibit gastric secretion.
Substances that stimulate gastric secretion include histamine, nicotine, adrenocorticotropic
steroids, insulin, and parasympathetic agents such as acetylcholine, reserpine, and pilocarpine.
Substances that inhibit gastric secretion include belladonna alkaloids (e.g., atropine), anticholinergic drugs (e.g., propantheline bromide [Pro-Banthine]), and histamine receptor antagonists (e.g., cimetidine, ranitidine). Aspirin causes changes in the gastric mucosa and decreases
the secretion of mucus by the stomach, resulting in insufficient protection of the stomach lining
from gastric juices.5
In the small intestine, digestion and absorption of nutrients are completed. This process is
accomplished by a combination of intestinal juices, pancreatic juices, and bile. As with the stomach, intestinal secretions consist of enzymes, hormones, and mucus. Intestinal enzymes include
peptidases, sucrase, maltase, lactase, intestinal lipase, intestinal amylase, and nucleases that
break down ingested proteins, carbohydrates, and fats so that they can be absorbed from the
small intestine into the blood. In addition, enterokinase is secreted. This enzyme activates
trypsin, a peptidase secreted by the pancreas. Other pancreatic enzymes include chymotrypsin,
carboxypeptidase, pancreatic amylase, pancreatic lipase, and nuclease.
Normally, 1200 to 1500 mL of duodenal juices are secreted each day. Digestive juices are clear,
have a high bicarbonate content, and range in pH from 8.0 to 8.5. As noted previously,
hormones secreted by the small intestine include secretin and CCK-PZ. When acidic gastric
contents enter the duodenum, the resultant decrease in pH stimulates the mucosal cells of the
small intestine to produce secretin. Secretin stimulates secretion of pancreatic juices that have a
high bicarbonate content. CCK-PZ also stimulates the pancreas to release its juices, especially
enzymes, although the source of the stimulation in this case is thought to be from the presence
of polypeptides or fatty acids in the small intestine.6
Tests of gastric and intestinal secretions include analysis of contents and tests of normal function (e.g., tests that stimulate gastric and duodenal secretions). Most of these tests involve insertion of a nasogastric (NG) or intestinal tube and may be quite uncomfortable for the client.
Newer nonlaboratory procedures are beginning to replace tests of gastric and intestinal secretions. Such procedures are more accurate, less time consuming, and less uncomfortable for the
client because they do not require long-term tube insertion. These newer procedures include
endoscopy; various radiologic techniques; measurement of hydrogen ion concentration (pH)
via electrodes in the endoscopy tube; radioimmunoassay of serum gastrin levels; cytologic
examination of gastric contents for malignant cells; and serum analysis of intrinsic factor, antiintrinsic factor antibodies, and antiparietal cell antibodies.7,8 Many of these tests are not widely
used at this time; only those tests in more common use are discussed in this chapter.

TESTS OF GASTRIC SECRETIONS
ANALYSIS OF GASTRIC CONTENTS
Gastric fluid analysis has two major components:
(1) macroscopic analysis and (2) microscopic analysis. Macroscopic analysis includes examination of
the specimen for overall physical and chemical characteristics such as color, presence of mucus and
blood, and pH determination. Microscopic analysis
involves examination of the specimen for organisms
such as bacteria and parasites. Cytologic examination for abnormal (i.e., malignant) exfoliated cells
may also be undertaken, although special techniques
must be used so that the cells are not destroyed
before analysis.

Specimens for gastric analysis are normally
collected in the morning after the client has been
fasting for 12 hours. Approximately 20 to 100 mL of
gastric fluid should be present in the stomach at that
time. If digestion is normal and the client has
observed fasting instructions, no food particles
should be present.9
MACROSCOPIC ANALYSIS

Color. Gastric juice is normally a translucent, pale
gray, slightly viscous fluid. If the gastric aspirate is
yellow to green, the presence of bile is indicated.
This finding may be a result of reflux of bile from
excessive gagging when the NG tube was inserted for
the test or it may indicate an obstruction in the

CHAPTER 12—Analysis

small intestine distal to the ampulla of Vater, the site
of bile secretion into the small intestine.10 Pink, red,
or brownish gastric secretions indicate the presence
of blood (see later discussion).
Mucus. Mucus is normally present in gastric secretions and derives mainly from the mucus secreted by
the gastric glands. The mucous content is responsible for the viscosity of gastric secretions. Saliva may
also contribute to the mucous content, but it is
frothy and tends to float on top of the sample. In
tests of gastric secretions, clients are instructed to
expectorate saliva during the test so as not to
contaminate the sample. If mucus from the respiratory tract is present, it tends to be more tenacious
than are gastric secretions and sometimes contains
dust particles. Small amounts of mucus from
duodenal reflux may also be present in the sample.11
Blood. Blood is not normally present in gastric
secretions. Small particles or streaks of fresh blood
may be present because of trauma during NG intubation. Larger amounts of blood or “coffee-ground”
material indicates bleeding of a greater magnitude
and is usually a result of some type of gastric lesion
(e.g., ulcer, gastritis, carcinoma). Blood swallowed
from the mouth, nasopharynx, or lungs may also be
present in the sample. Regardless of whether overt
blood appears in the sample, the specimen should
always be tested for blood.12
pH. The pH of gastric secretions is usually less than
2.0 and is not normally greater than 6.0 if gastric
secretion is normal. Lack of normal gastric acidity is
seen in pernicious anemia; gastric carcinoma; aplastic or hypochromic anemia; and immune-related
disorders of the thyroid, stomach, and connective
tissue. Elevated pH in gastric juice also supports
ruling out peptic ulcer disease as a diagnosis.13 In
addition to peptic ulcer disease, low pH levels are
seen in Zollinger-Ellison syndrome (non--cell
adenomas of the pancreas that produce excessive
gastrin).
MICROSCOPIC ANALYSIS

Red Blood Cells. As noted earlier, the presence of a
few red blood cells may be a result of the trauma of
gastric intubation. Larger numbers, however, may
indicate serious disorders and require additional
diagnostic follow-up.
White Blood Cells. Normally, a few white blood
cells are present in gastric juices. Elevated numbers
may indicate inflammation of the gastric mucosa,
mouth, paranasal sinuses, or respiratory tract. White
blood cells found in gastric aspirates may also be
present because of inflammation of the duodenum,

of Gastric and Duodenal Secretions

313

pancreas, or biliary tract, although it is a less
common finding.14
Epithelial Cells. A few epithelial cells are normally
present because of sloughing from mucosal surfaces.
The presence of clumps of cells may be caused by
dislodgment during intubation. Gastritis may also
lead to the finding of increased epithelial cells in
gastric fluid.
Bacteria and Yeasts. Because of the highly acidic
environment of the stomach, bacteria are not
normally found in gastric contents. In most cases,
those bacteria (and yeasts) that are cultured from
gastric fluid are normal flora of the mouth or respiratory tract. Increased numbers of bacteria may be
found in gastric contents that have an abnormally
high pH. Excessive numbers of yeasts are associated
with retention of gastric contents because of some
type of blockage (e.g., pyloric obstruction).15
Cultures for Mycobacterium tuberculosis are made in
individuals who are suspected of having pulmonary
tuberculosis but who are unable to expectorate
sputum effectively for analysis. Gastric samples for
cytology are best collected through procedures
designed to cause cells to exfoliate (i.e., exfoliative
cytology). In addition to gastric aspiration, samples
can be obtained by gastroscopy and use of balloons
and brushes. The best method is said to be gastric
lavage with a solution containing chymotrypsin.16
Parasites. Parasites may be found in gastric fluid,
mainly resulting from reflux of duodenal contents.
Such parasites include Giardia lamblia, trophozoites
or cysts, Strongyloides larvae, and hookworm ova.
INTERFERING FACTORS

Failure to follow dietary restrictions so that food
particles are present
Exposure to the sight, smell, or thought of food
immediately before the test
Ingestion of drugs that may alter gastric secretions (e.g., alcohol, histamine, nicotine, adrenocorticotropic steroids, insulin, parasympathetic
agents, belladonna alkaloids, anticholinergic
drugs, histamine receptor antagonists, aspirin)
Contamination of the sample with saliva and
respiratory secretions, which should be expectorated rather than swallowed during the procedure
Failure to send the samples to the laboratory
promptly for analysis of cells, which can disintegrate in gastric juices
INDICATIONS FOR ANALYSIS OF GASTRIC
CONTENTS

Suspected peptic ulcer disease, as indicated by low

314

SECTION I—Laboratory

Tests

Reference Values
Macroscopic Analysis
Volume (fasting)

20–100 mL

Color

Pale gray, translucent

Mucus

Present such that the sample is slightly viscous

Blood

Negative

2.0 (never 6.0)
Microscopic Analysis

Red blood cells

Negative to a few

White blood cells

Negative to a few

Epithelial cells

Few

Bacteria

Absent to few

Yeasts

Absent to few

Parasites

Absent

Abnormal cells

Absent

to normal pH and (possibly) the presence of
blood
Suspected Zollinger-Ellison syndrome, as indicated by low to normal pH
Suspected gastric carcinoma, as indicated by lack
of normal gastric acidity, blood (possibly), and
abnormal cells on cytologic examination
Suspected pernicious anemia as indicated by lack
of normal gastric acidity
Suspected pulmonary tuberculosis, as indicated
by positive cultures for M. tuberculosis
Suspected parasitic infestation of the gastrointestinal tract
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The purpose of the test (Note: Gastric analysis is
often performed as a component of specific tests
for gastric acidity.)
That fasting for 12 hours before the test is necessary, although water may be permitted up to 8
hours before the test
That smoking is not permitted for 8 hours before
the test
That certain medications may be withheld, on the
physician’s order, for up to 24 hours before the test
That a stomach tube will be passed through the
nose or mouth into the stomach
That the client will be asked to swallow periodically when the tube is passed, as swallowing facilitates tube passage
That the tube may cause a sensation of burning or

irritation as it is passed and that gagging may
occur when the tubing touches the back of the
throat
That saliva and respiratory secretions should be
expectorated rather than swallowed during the
test
That a sample of stomach juices will be removed
via the tube
That the tube will be removed on completion of
the test
Prepare for the procedure:
Ensure to the extent possible that dietary, smoking, and medication restrictions are followed.
Provide the client with a hospital gown.
Ensure that an informed consent has been
obtained and signed, if required.
THE PROCEDURE

The equipment needed is assembled, including an
NG tube, lubricant, gloves, 50-mL syringe adapted
for use with NG tube, saline, and specimen containers with appropriate labels. Tissues and an emesis
basin also should be available for expectoration of
secretions by the client.
With the client seated comfortably, the NG tube is
passed into the stomach and the syringe is attached.
All gastric contents are aspirated, placed in a
container, and labeled. If a specimen for tubercle
bacilli is to be obtained, gastric washings with saline
may be performed to obtain the sample. This procedure is accomplished by irrigating the NG tube with
saline and withdrawing the contents.

CHAPTER 12—Analysis

When all needed samples are obtained, the NG
tube is removed. The samples should be sent to the
laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include assisting
the client to a position of comfort. Provide mouth
and nose care. Resume any foods and medications
withheld for the test.
Administer lozenges to alleviate sore throat
caused by irritation by the tube.
Assess the client’s comfort level.
Assess the client’s ability to resume normal food
and fluid intake.
Assess for sore throat, abdominal pain, and
nausea; administer gargle, lozenge, or ordered
medication to control nausea or pain.

TESTS OF GASTRIC ACIDITY
Tests of gastric acidity are used to determine the
presence and amount of hydrochloric acid in the
stomach and to diagnose disorders associated with
altered secretion of gastric acids. Three main types
of tests are used to evaluate gastric acidity: (1) basal
gastric acidity test, (2) gastric acid stimulation tests,
and (3) tubeless gastric analysis test. The basal
gastric acidity test usually is performed with tests of
gastric acid stimulation.
BASAL GASTRIC ACIDITY TEST

This test is used to determine elevated gastric acidity, which is seen in Zollinger-Ellison syndrome and
peptic ulcer disease. The sample is examined for
volume, pH, and total acid secretion in each specimen as well as in the total sample. Total acid secretion is expressed as basal acid output (BAO) in
milliequivalents per hour. The BAO is somewhat
lower in elderly people and in women and varies
directly with body weight.17
GASTRIC ACID STIMULATION TESTS

Gastric acid stimulation tests are performed to
determine the response to substances that are
administered to induce increased gastric acid secretion. Elevated acid output is associated with peptic
ulcer disease and Zollinger-Ellison syndrome.
Decreased acid output is usually associated with
pernicious anemia and gastric carcinoma; however,
it may also be seen in a variety of other disorders,
including hypochromic anemia, nutritional megaloblastic anemia, steatorrhea, rheumatoid arthritis,
and myxedema.
Substances used to induce gastric secretion in
these tests include histamine, betazole, and pentagastrin, with the latter being the drug of choice.

of Gastric and Duodenal Secretions

315

Histamine is a substance that occurs naturally in the
body and is implicated in various allergic and
inflammatory responses. It also has the effect of
stimulating gastric acid secretion. Unfortunately,
when used for gastric acid stimulation tests, histamine produces numerous unpleasant side effects
such as flushing, bradycardia, headache, nasal stuffiness, lacrimation, and alterations in blood pressure.18 Betazole is an analogue of histamine that also
produces increased gastric acid secretion but more
slowly. It has minimal side effects but requires a
longer testing period when used for gastric acid
stimulation tests. Pentagastrin is a synthetic
compound that induces gastric secretion as rapidly
as histamine but without major side effects. For
these reasons, it is the current drug of choice for
gastric acid stimulation tests.
As with basal gastric acidity tests, samples
obtained from gastric acid stimulation tests are
examined for volume, pH, and amount of acid
secreted. First, BAO is determined. Maximum acid
output (MAO) is also determined by adding the
total milliequivalents of acid secreted in all samples
after injection of the gastric acid stimulant.19 Peak
acid output may also be determined by adding the
greatest acid output in two consecutive 15-minute
samples. Finally, BAO and MAO are compared as a
ratio, which normally ranges from 0.3 to 0.6. That is,
the maximum output should be 1 1/2 to 3 times the
basal output.20
Hollander Insulin Test. This test is used to evaluate
the effectiveness of vagotomy (i.e., severing vagal
nerve connections to the stomach) as a treatment for
persistent peptic ulcer disease and involves stimulation of the vagus nerve through insulin-induced
hypoglycemia. Hypoglycemia is normally a potent
stimulator of gastric secretions and causes impulses
to be transmitted via the vagus nerve. If the vagus
nerve has been severed, however, the normal physiological response does not occur.
This test is not used very frequently, because it
can be dangerous for the client (i.e., a blood sugar
of less than 45 to 50 mg/dL is needed to provoke
gastric secretion). In addition, data from the test
do not always provide a clear distinction between
normal and abnormal results; false-positive and
false-negative results are common, and the results
do not correlate strongly with recurrent ulcer
disease.
INTERFERING FACTORS

Failure to follow dietary restrictions, resulting in
stimulation of gastric secretions
Exposure to the sight, smell, or thought of food
immediately before and during the test

316

SECTION I—Laboratory

Tests

Reference Values
Volume

20–100 mL (usually 30–60 mL)

Basal acid output

2–6 mEq/hr (Values may be slightly lower in women
and elderly persons; values vary directly with body weight.)

Maximum acid output

16–26 mEq/hr or at least 11/2–3 times the BAO (after stimulation tests)

BAO:MAO ratio

0.3–0.6 (usually 0.4)

Ingestion of drugs that may alter gastric secretions (e.g., alcohol, histamine, nicotine, adrenocorticotropic steroids, insulin, parasympathetic
agents, belladonna alkaloids, anticholinergic
drugs, and histamine receptor antagonists) unless
administered as part of the testing procedure
Dilution of the samples with saliva and respiratory secretions, which should be expectorated
during the test
INDICATIONS FOR TESTS OF GASTRIC ACIDITY

Suspected duodenal ulcer as indicated by elevated
BAO (5 to 7 mEq/hr) and MAO (greater than 40
mEq/hr) (Individuals with stomach ulcers may
have low to normal BAO and MAO.)
Suspected Zollinger-Ellison syndrome as indicated by elevated BAO, normal or elevated MAO
(elevated MAO after gastric stimulation is
frequently not seen in these individuals because
gastric acid output is already at maximum levels),
and a high BAO:MAO ratio
Suspected pernicious anemia as indicated by
decreased or absent gastric acid output with BAO,
MAO, and BAO:MAO ratio frequently at 0
Suspected gastric carcinoma as indicated by
decreased BAO (e.g., 1.0 mEq/hr), decreased
MAO (e.g., 4.0 mEq/hr), and decreased
BAO:MAO ratio (e.g., 0.25)
Evaluation of effectiveness of vagotomy in the
treatment of peptic ulcer disease as indicated by
absence of response to gastric stimulation with
insulin (Hollander insulin test)

that insulin will be injected intravenously (IV) to
lower the blood sugar and should be reassured
that glucose will be available for administration if
necessary.
The client should also be advised that it may be
necessary to insert an intermittent venous access
device (e.g., heparin lock).
The client should be informed that it takes
approximately 2 to 3 hours to complete this test.
Vital signs should be monitored.
Depending on the institution, signed consents
may be required for gastric acid stimulation tests
because they involve injection of drugs.
THE PROCEDURE

Equipment needed for the tests subsequently
discussed is essentially the same as that described in
the “Analysis of Gastric Contents” section. In some
institutions, the serial gastric aspirates are obtained
by connecting the NG tube to a suction device.
Manual aspiration of gastric contents is, however,
the preferred approach. For the Hollander insulin
test, equipment to insert an intermittent venous
access device (i.e., heparin lock) will be needed, as
well as a syringe of 50 percent glucose.

NURSING CARE BEFORE THE PROCEDURE

Basal Gastric Acidity Test. An NG tube is inserted
and the stomach contents aspirated. The tube is
clamped. After 15 minutes, the tube is opened and
the gastric contents aspirated. This procedure is
continued until a total of four samples have been
obtained. Each sample is labeled with the time and
sequence of collection. The samples should be transported promptly to the laboratory.

Client preparation is essentially the same as that for
analysis of gastric contents (see section under
“Analysis of Gastric Contents”).
For gastric stimulation tests using pentagastrin,
betazole, or histamine, the client should be
informed that a medication will be injected to
increase stomach secretions and that the test
requires 2 to 3 hours for completion.
The client should be advised to report unusual
symptoms such as flushing, headache, nasal stuffiness, dizziness, faintness, and nausea.
For the insulin test, the client should be informed

Gastric Acid Stimulation Tests. A basal gastric
acidity test is performed; then the gastric stimulant
(pentagastrin, betazole, or histamine) is injected
subcutaneously. For pentagastrin and histamine
tests, gastric samples are obtained at 15-minute
intervals for 1 hour after injection of the drug; for
betazole, the samples are obtained at 15-minute
intervals for 2 hours after drug injection. If side
effects of the drugs become severe, epinephrine or
ephedrine may be administered. These drugs antagonize the effects of histamine, except for effects on
gastric secretions.21

CHAPTER 12—Analysis

Hollander Insulin Test. A 2-hour basal gastric acidity test is performed. A baseline blood sugar level is
then measured. An intermittent venous access device
(i.e., heparin or saline lock) may also be inserted for
administration of insulin and for glucose, if extreme
hypoglycemia should occur. This device can also be
used to obtain blood sugar samples during the test.
Regular insulin is then administered in a dosage of
15 to 20 units or 0.2 units per kilogram of body
weight. Gastric aspirates are then obtained every 15
minutes for 2 hours. Blood glucose determinations
also are made at 30, 60, and 90 minutes after injection of the insulin.
A syringe of 50 percent glucose should be available for administration if extreme hypoglycemia
occurs. Sweetened orange juice or milk may also be
administered orally, if necessary. Note that a blood
sugar level of 45 to 50 mg/dL is needed to provoke
gastric secretions.
All specimens are labeled with the time and
sequence of collection. The NG tube and venous
access device are removed on completion of the test.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test are the same as for
analysis of gastric contents (see section under
“Analysis of Gastric Contents”).
Gastric stimulation tests: Monitor vital signs
after the test and assess the client for side effects of
drugs administered to induce gastric secretions.
Hollander insulin test: Monitor for hypoglycemia and resume dietary intake immediately
at the conclusion of the test.

TESTS OF DUODENAL
SECRETIONS
ANALYSIS OF DUODENAL CONTENTS
Duodenal fluid analysis is used mainly to evaluate
clients with chronic pancreatitis or suspected carcinoma of the pancreas. It can also be used in evaluating infants with suspected cystic fibrosis or with
diarrhea or steatorrhea of unknown etiology.22
Duodenal fluid samples are more difficult and
time consuming to obtain than are gastric samples.
Duodenal samples are obtained by inserting a
double-lumen tube. One lumen opens into the
stomach and drains gastric secretions so that they do
not interfere with duodenal fluid analysis. The end
of the tube is positioned near the ampulla of Vater so
that the second lumen actually drains duodenal and
pancreatic fluids. Correct tube placement must be
confirmed by fluoroscopic radiologic procedures.
Duodenal samples can be obtained during endoscopic procedures.
Specimens for duodenal analysis are usually

of Gastric and Duodenal Secretions

317

collected in the morning, after the client has been
fasting for 12 hours. Approximately 20 mL of
duodenal fluid should be obtained at that time. If
digestion is normal and if the client has observed
fasting instructions, no food particles should be
present.
MACROSCOPIC ANALYSIS

Color. Duodenal secretions are normally pearly
gray, translucent, and moderately viscous. Yellow or
green coloration indicates that bile is present, but
this finding is generally of no major clinical significance. Pink, red, or brownish secretions may indicate the presence of blood (see next paragraph). If
food particles are present, it may indicate failure to
follow dietary restrictions, intestinal obstruction, or
duodenal diverticula.23
Blood. Blood is not normally present in duodenal
secretions. Small particles or streaks of fresh blood
may be present because of the trauma of intubation.
Larger amounts of blood suggest pancreatic carcinoma.
pH. The pH of duodenal fluid normally ranges
from 8.0 to 8.5. Increased pH is associated with
chronic pancreatitis.
Bicarbonate. Bicarbonate may be measured as part
of a routine analysis but is more likely to be determined as part of stimulation tests. Decreased bicarbonate levels are seen in chronic pancreatitis.
MICROSCOPIC ANALYSIS

Red Blood Cells. As previously noted, the finding of
red blood cells may indicate intubation trauma or
carcinoma of the pancreas.
White Blood Cells and Epithelial Cells. Normally,
a few white blood cells and epithelial cells are present in duodenal aspirates. Larger amounts are associated with inflammation of the duodenum, bile
ducts, or pancreas.
Bacteria. Bacteria are not normally present in
duodenal secretions because of the effects of gastric
acid. Samples for routine analysis are rarely cultured
for bacteria.
Parasites. Parasites are rarely seen in duodenal
secretions. When present, they usually consist of the
following: (1) larvae of Strongyloides stercoralis, (2)
cysts or trophozoites of Giardia lamblia or Entamoeba histolytica, and (3) ova of Necator, Ancylostoma, or Ascaris.24
INTERFERING FACTORS

Failure to follow dietary restrictions, resulting in
the presence of food particles in the aspirate

318

SECTION I—Laboratory

Tests

Reference Values
Conventional Units

SI Units

Macroscopic Analysis
Volume (fasting)

20 mL

Color

Pearl gray, translucent

Blood

Negative

8.0–8.5

Bicarbonate

145 mEq/L

145 mmol/L

Microscopic Analysis
Red blood cells

Negative

White blood cells

Few

Epithelial cells

Few

Bacteria

Negative

Parasites

Negative

Improper tube placement, resulting in aspiration
of gastric secretions
INDICATIONS FOR ANALYSIS OF
DUODENAL CONTENTS

Suspected carcinoma of the pancreas as indicated
by decreased volume, presence of blood (possibly), and normal bicarbonate
Known or suspected chronic pancreatitis as indicated by decreased volume, pH, and bicarbonate
Suspected cystic fibrosis as indicated by decreased
volume, pH, and bicarbonate
Suspected infestation with parasites, especially
G. lamblia
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The purpose of the test (Note: Analysis of duodenal contents is often performed as a component of
duodenal stimulation tests.)
That fasting from foods and fluids for 12 hours
before the test is necessary
That smoking is not permitted for 8 to 12 hours
before the test
That a tube will be passed through the mouth or
nose into the small intestine
That various positions may be required (e.g.,
sitting, lying on side or back) while the tube is
passed (see “The Procedure” section next)
That the client may be asked to swallow or deepbreathe periodically as the tube is passed
That a mild sedative may be administered before
insertion of the tube

That the tube may cause a sensation of burning as
it is passed and that gagging may occur when the
tube touches the back of the throat
That tube placement will be checked by an x-ray
examination
That a sample of juices from the small intestine
will be removed from the tube by using a suction
apparatus
That the tube is removed on completion of the
test
Prepare for the procedure:
Assess the client’s degree of mobility, because the
client must assume various positions (sitting,
side-lying, back-lying) while the tube is passed. If
the client’s mobility is impaired, the individual
performing the test should be so informed so that
sufficient assistance is available for client positioning.
A signed consent may be required for this test,
depending on the institution.
Ensure to the extent possible that dietary and
smoking restrictions are followed.
Provide the client with a hospital gown.
THE PROCEDURE

The needed equipment is assembled, including a
double-lumen intestinal tube to aspirate duodenal
contents, lubricant, gloves, 20- or 50-mL syringe
adapted for use with the intestinal tube, and
specimen containers. Tissues and an emesis
basin also should be available for client use. A
mechanical suction device for removing gastric
secretions continuously during the test will be

CHAPTER 12—Analysis

needed, as will a suction device for removing
duodenal secretions.
With the client seated comfortably, the doublelumen tube is passed into the upper part of the
stomach. The client is then positioned on the left
side and the tube is passed into the lower part of the
stomach. The client is then assisted to a sitting position and asked to lean forward from the waist as far
as possible. He or she also is instructed to take
several deep breaths at this time, which should move
the tip of the tube into the portion of the stomach
near the pyloric sphincter. The client is then assisted
to lie on the right side; this position, along with
normal peristalsis, should move the tube into the
duodenum. The client is then assisted to a backlying position and the tube advanced another 10 to
15 cm. Approximately 15 minutes are required to
pass the tube in this manner. Under fluoroscopic
visualization, the tube is positioned so that the tip is
in the middle of the third portion of the duodenum,
distal to the ampulla of Vater.25 When proper location of the tube is ascertained, the tube is secured to
the client’s face with tape.
The gastric lumen of the tube is connected to a
suction device throughout the procedure. Duodenal
secretions are collected by mechanical suction for 20
minutes and then sent to the laboratory for analysis.
The gastric aspirate is discarded. If tests of duodenal
stimulation are to be made, they will be performed
before removal of the intestinal tube.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test are the same as
that for analysis of gastric contents (see section
under “Analysis of Gastric Contents”).
If a sedative has been administered, delay resumption of diet, fluid intake, and activity until the
medication has worn off.
Assess the client’s comfort level.
Assess the client’s degree of sedation and take
appropriate safety measures.
Assess the client’s ability to resume normal food
and fluid intake.
Provide support when diagnostic findings are
revealed, and assist the client in coping with
possible acute or chronic disorder and therapy.

of Gastric and Duodenal Secretions

319

DUODENAL STIMULATION TESTS
Duodenal stimulation tests involve administering
substances that stimulate pancreatic secretion and
then measuring the pancreatic substances as they
appear in duodenal aspirates. Two such tests are
performed: (1) secretin test and (2) cholecystokininpancreozymin test.
SECRETIN TEST

Secretin is a hormone normally secreted by the
small intestine. It acts to stimulate the pancreas to
secrete increased volumes of pancreatic juices
with high bicarbonate content. In this test, secretin
is administered IV (1 clinical unit per kilogram of
body weight) and three duodenal samples are aspirated at 20-minute intervals. A decreased response
to secretin is seen in any disorder characterized by
chronic inflammation and scarring of the pancreas
(e.g., chronic pancreatitis). This test may also aid
in diagnosing carcinoma of the pancreas, because
bicarbonate values in this disorder are higher than
in chronic pancreatitis after stimulation with
secretin. Deficiency in pancreatic secretion also is
associated with cystic fibrosis. The main use of
this test, however, is to monitor declining pancreatic function in individuals with chronic pancreatitis.26
CHOLECYSTOKININ-PANCREOZYMIN TEST

Cholecystokinin-pancreozymin (CCK-PZ) is a
hormone normally secreted by the small intestine. It
acts to stimulate the pancreas to secrete increased
amounts of pancreatic enzymes. This test, which is
sometimes performed after the secretin test, involves
administration of CCK-PZ and then aspiration of
duodenal secretions. The aspirated samples are then
assayed for the pancreatic enzymes amylase, lipase,
or trypsin, with amylase the enzyme most
commonly measured. The results of this test generally parallel those of the secretin test; that is, if overall pancreatic function is decreased, enzyme
production is also decreased.
INTERFERING FACTORS

Failure to follow dietary restrictions, resulting in

Reference Values
Conventional Units
Volume

2–4 mL/kg body weight

Bicarbonate

90–130 mEq/L

Pancreatic amylase

6.6–35.2 U/kg body weight

SI Units

90–130 mmol/L

320

SECTION I—Laboratory

Tests

stimulation of pancreatic secretion by food particles
Improper tube placement, resulting in aspiration
of gastric secretions
INDICATIONS FOR DUODENAL STIMULATION
TESTS

Monitoring of the progression of chronic pancreatitis, with worsening disease indicated by
decreased volume, decreased bicarbonate, and
decreased enzyme secretion
Suspected cancer of the pancreas as indicated by
decreased volume, normal bicarbonate, and
decreased enzyme secretion
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as that for routine
analysis of duodenal contents (see section under
“Analysis of Duodenal Contents”).
The client should be informed that a medication
will be administered to stimulate pancreatic secretion.
Intradermal skin tests to determine sensitivity to
secretin or CCK-PZ, or both, may be performed
before the test.
Because secretin is administered IV, an intermittent venous access device (i.e., heparin lock) may
be inserted for the test.
THE PROCEDURE

The procedure begins with aspiration of baseline
(fasting) duodenal secretions (see section under
“Analysis of Duodenal Contents”). For the secretin
test, secretin is administered IV in the amount of 1
clinical unit per kilogram of body weight. Three
samples of duodenal aspirate are then obtained at
20-minute intervals. For the CCK-PZ test, the

hormone is administered and samples for pancreatic
enzymes (usually amylase) are withdrawn.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for analysis of duodenal contents (see
section under “Analysis of Duodenal Contents”).
Monitor for allergic reactions to the hormones
even though skin tests have been negative.
REFERENCES
1. Porth, CM: Pathophysiology: Altered States of Health, ed 5. JB
Lippincott, Philadelphia, 1998, p 713.
2. Price, S, and Wilson, L: Pathophysiology: Clinical Concepts of
Disease Process, ed 5. Mosby, St Louis, 1997, p 329.
3. Porth, op cit, p 714.
4. Hole, JW: Human Anatomy and Physiology, ed 4. Wm C Brown,
Dubuque, Iowa, 1987, p 506.
5. Porth, op cit, p 724.
6. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, p 754.
7. Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis,
Philadelphia, 2001, p 215.
8. Kao, YS, and Liu, FJ: Laboratory diagnosis of gastrointestinal tract.
In Henry, JB: Clinical Diagnosis and Management by Laboratory
Methods, ed 18. WB Saunders, Philadelphia, 1991, p 519.
9. Ibid, p 521.
10. Ibid, p 521.
11. Ibid, p 521.
12. Ibid, p 521.
13. Sacher and McPherson, op cit, p 752.
14. Kao and Liu, op cit, p 522.
15. Ibid, p 522.
16. Ibid, p 524.
17. Sacher and McPherson, op cit, pp 751–752.
18. Kao and Liu, op cit, p 522.
19. Ibid, p 520.
20. Sacher and McPherson, op cit, pp 751–752.
21. Bergensen, BS: Pharmacology in Nursing, ed 14. Mosby–Year Book,
St Louis, 1979, p 700.
22. Kao and Liu, op cit, p 526.
23. Ibid, p 525.
24. Ibid, pp 525–526.
25. Kao and Liu, op cit, p 525.
26. Sacher and McPherson, op cit, p 754.

CHAPTER

Fecal Analysis
TESTS COVERED
Microscopic Analysis of Feces, 321
Tests for Specific Substances in Feces,
325

Microbiologic Tests of Feces, 329

COMPOSITION AND CHARACTERSTICS OF FECES

Feces consist mainly of cellulose and other undigested foodstuffs, bacteria, and water (as much as 70 percent). Other
substances normally found in stools include epithelial cells shed from the gastrointestinal tract,
small amounts of fats, bile pigments in the form of urobilin (see Fig. 6–1), gastrointestinal and
pancreatic secretions (see Chapter 12), and electrolytes.1,2 The average adult excretes 100 to 300
g of fecal material per day, the residue of approximately 10 L of liquid material that enters the
intestinal tract each day.3
Feces are normally brown because of bacterial degradation of bile pigments to stercobilin.
The characteristic odor of feces is caused by bacterial action on proteins and other residues that
produce substances such as indole, skatole, phenol, hydrogen, sulfide, and ammonia.4 The
normal consistency of feces is described as “plastic”; that is, stools should not normally be
liquid, mushy, or hard.5 The shape and caliber of normal stools is the same as that of the distal
colon.
Alterations in color, odor, consistency, or shape may indicate the presence of disease.
Although these characteristics are not always specifically studied in the laboratory, the nurse
may observe them when providing care. Feces that are abnormal in terms of gross characteristics require additional diagnostic follow-up. Table 13–1 depicts normal and abnormal characteristics that may be observed and possible causes of alterations.
Laboratory analysis of feces includes microscopic examinations, chemical tests for specific
substances, and microbiologic tests. Laboratory analysis of feces is performed much less
frequently than are studies of blood, urine, and other body fluids. One reason for this is that
clients and health-care providers dislike collecting stool specimens. Furthermore, fecal samples
cannot usually be collected on demand the way blood samples can, with the possible exception
of small samples obtained during rectal examination, which may be sufficient for screening
tests (e.g., occult blood). Despite these disadvantages, analysis of fecal material aids in diagnosing gastrointestinal and other disorders.6

TESTS OF FECES
MICROSCOPIC ANALYSIS OF FECES
Microscopic analysis of stool specimens includes

examining the sample for leukocytes, epithelial cells,
qualitative fat, meat fibers, and parasites. These tests
can be performed singly, in combination with other
tests, or as routine screening tests.
321

322

SECTION I—Laboratory

TABLE 13–1
Characteristic

•

Tests

Normal and Abnormal Gross Characteristics of Feces

Normal

Volume

100–300 g

Odor

Pungent

Shape/caliber

Shape and
caliber of the
distal colon

Alterations

Possible Causes of Alterations

Large volume, malodorous,
floating

Malabsorption of fats or proteins
Cystic fibrosis, pancreatitis, postgastrectomy syndrome, bile duct obstruction,
primary small bowel disease

Large caliber

Dilatation of the colon

Small, ribbonlike

Decreased elasticity of the colon
Partial bowel obstruction

Color

Brown

Red

Lower GI tract bleeding
Red beet ingestion
Bromsulphalein dye, phenazopyridine
(Pyridium) compounds

Black

Upper GI tract bleeding
Charcoal, licorice, iron, or bismuth
ingestion

Dark brown

Hemolytic anemia
Diet high in meat
Prolonged exposure of the sample to air

Gray

Chocolate and cocoa ingestion

Gray, silvery

Steatorrhea

Pasty, gray-white

Barium ingestion
Bile duct obstruction

Very pale gray

Diet high in milk products

Green, yellow-green

Ingestion of spinach, other greens, laxatives of vegetable origin,
indomethacin
Rapid transit time through the intestine,
preventing oxidation of bile pigments

Green-black

Meconium, infant

Green-yellow (watery)

Transitional stool, infant

Yellow, pasty

Breast-fed infant

Yellow-brown

Cow’s milk–fed infant

LEUKOCYTES

Examination of feces for leukocytes, especially
neutrophils and monocytes, is usually performed in
the initial evaluation of diarrhea of unknown etiology. Testing for the presence or absence of leukocytes

can provide important diagnostic clues, and these
tests yield results faster than do stool cultures.
EPITHELIAL CELLS

Normally small to moderate numbers of epithelial
cells are present in feces. Large numbers of epithelial

CHAPTER 13—Fecal

TABLE 13–1
Characteristic
Consistency

•

323

Normal and Abnormal Gross Characteristics of Feces

Normal
Plastic

Analysis

Alterations

Possible Causes of Alterations

Small, round, hard masses

Habitual constipation

Mucoid, watery but without
blood

Irritable bowel syndrome, diffuse superficial bowel inflammation, villous
adenoma

Mucoid, bloody

Inflammatory bowel syndrome, carcinoma, typhoid, Shigella, amebae

Sticky, tarry, black

Upper GI tract bleeding

Voluminous, watery, littleformed material

Osmotic catharsis
Noninvasive infections (cholera toxigenic, Escherichia coli, staphylococcal
food poisoning)

Mucus

Absent

Loose, purulent, or with
necrotic tissue

Diverticulitis, abscess, necrotic tumor,
parasites

Present

Colitis, bacillary dysentery, diverticulitis,
carcinoma

Adapted from Sacher, RA, and McPherson, RA: Widmonn’s Clinical Interpretation of Laboratory Tests, ed 11.
FA Davis, Philadelphia, 2000, pp 751–752, with permission.

cells (or large amounts of mucus), however, indicate
that the intestinal mucosa is irritated.7
QUALITATIVE FATS

Fats are found in the feces primarily in the forms of
triglycerides (neutral fats), fatty acids, and fatty acid
salts. Their presence is determined through various
staining techniques before microscopic examination. Through these methods, the number of fat
droplets and their size can be determined, and the
type of fat can be identified. The finding of more
than 60 fat droplets per high-power field (HPF)
usually indicates steatorrhea, which simply means
excess fat in the stool. The size of the droplet also
must be considered in arriving at a diagnosis. The
fat droplets in steatorrhea are usually larger than
normal.
Excess fat in the stool is usually caused by either
malabsorption syndromes or deficiency in pancreatic enzymes. Microscopic examination for fecal fat
may aid in differentiating between these two disorders. An increase in triglycerides generally indicates
a deficiency of pancreatic enzymes that normally
break down triglycerides to fatty acids. In contrast,
individuals with malabsorption syndromes usually
have normal amounts of triglycerides in their stools
but excessive fatty acids because these clients are
unable to absorb the fats once they are broken
down.8 Other causes of excessive fecal fat include
surgical resection or fistulas of the intestines and

recent intake of excessive amounts of dietary fats.
False-negative results may occur in individuals with
malabsorption problems who restrict their fat intake
because of anorexia.
Microscopic tests for fecal fats are essentially qualitative in nature. The test simply indicates whether
excessive fat is present and, if so, the nature of that
fat. The definitive test for evaluating steatorrhea is
quantitative analysis for fecal fat. This evaluation is
accomplished through a 72-hour stool collection
while the client is on a diet containing 100 g of fat
per day (see later discussion on quantitative fats).9
MEAT FIBERS

Microscopic examination of stool specimens for
meat fibers aids in evaluating the efficiency of digestion. If protein digestion is adequate, meat fibers will
not be found. If they are present, inadequate proteolysis is indicated. The finding of meat fibers in feces
usually correlates positively with the finding of steatorrhea.10 Individuals who have difficulty digesting
proteins also have difficulty digesting fats.
PARASITES

Microscopic tests for parasites and their ova
augment observation of gross characteristics of
stools; that is, certain types of parasites (e.g., tapeworm segments) may be apparent in stool samples
without the aid of a microscope.11 Microscopic
analysis for parasites is usually indicated in individ-

324

SECTION I—Laboratory

Tests

Reference Values
Leukocytes

Negative

Epithelial cells

Few to moderate

Fat (qualitative)

60 normal-sized droplets per HPF

Triglycerides (neutral fats)

1–5%

Fatty acids

5–15%

Meat fibers

Negative

Parasites

Negative

uals with intestinal disorders of unknown etiology,
history of possible exposure to parasites, or
eosinophilia of unknown cause that could be a result
of parasitic infestation.
Parasites commonly found in stools include
roundworms (e.g., Ascaris lumbricoides), tapeworms
(e.g., Diphyllobothrium latum, Taenia saginata),
hookworms (e.g., Necator americanus), ameba (e.g.,
Entamoeba histolytica), and protozoa (e.g., Giardia
lamblia).12 In collecting specimens for parasites, the
sample must be transported immediately to the
laboratory. The best samples are considered to be
those that contain blood and mucus because they
are also most likely to contain parasites.
INTERFERING FACTORS

A diet too high or too low in fat may alter results
of qualitative tests for fats.
Failure to send fresh stool specimens to the laboratory immediately, thereby avoiding excessive
exposure to room temperature and air, may
damage any parasites so that they cannot be identified microscopically.
Contamination of the sample with urine or toilet
bowl water.
Use of laxatives for several days before the tests.
Presence of barium in the stool after x-ray procedures.
Antibiotic therapy.
INDICATIONS FOR MICROSCOPIC ANALYSIS
OF FECES

Abnormal appearance of stools (see Table 13–1)
Diarrhea of unknown etiology:
Diarrhea resulting from disorders involving the
intestinal wall (e.g., ulcerative colitis and bacterial infection with Salmonella, Shigella, Yersinia,
and invasive Escherichia coli) is associated with
the presence of leukocytes in the sample.
Diarrhea resulting from organisms that cause
diarrhea by toxin rather than by intestinal

wall damage (e.g., viruses, Staphylococcus,
noninvasive E. coli, Clostridium perfringens,
Vibrio cholerae, Giardia, Entamoeba) is associated with absence of leukocytes in the
sample.13,14
Suspected inflammatory bowel disorder as indicated by large numbers of epithelial cells
Suspected pancreatitis as indicated by excessive
fecal fat (steatorrhea) with elevated triglycerides
(neutral fats)
Suspected malabsorption syndromes as indicated
by steatorrhea, normal triglycerides, and elevated
fecal fatty acids
Suspected alteration in protein digestion as indicated by the presence of meat fibers
Suspected infestation with intestinal parasites,
ova, and viruses
Eosinophilia of unknown etiology, with suspicion
of parasitic infestation
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The importance of following a normal diet for
several days before the collection or notifying the
physician if this requirement cannot be met
The importance of not taking laxatives for several
days before the collection or notifying the physician if this avoidance is not possible
The method for collecting a sample of a bowel
movement (see section titled “The Procedure”)
The method for transferring the sample from the
specimen pan to the sample container (e.g., using
tongue blades; obtaining the sample from the
midportion of the stool, including any portion of
the stool with visible blood, mucus, pus, or parasites such as tapeworms)
The importance of not contaminating the specimen with urine or water
The importance of delivering the sample to the
laboratory within 30 to 60 minutes of collection or refrigerating the sample if it must be

CHAPTER 13—Fecal

stored longer than 60 minutes (Exception:
Samples for parasites cannot be refrigerated;
they must instead be received in the laboratory
while still warm.)
The importance of placing the sample in a tightly
covered container
Prepare for the procedure:
Ensure to the extent possible that the client has
followed a relatively normal diet and has not used
laxatives for several days before testing.
Provide a specimen collection container (e.g., a
plastic “hat” device, which is placed under the
toilet seat), gloves, and tongue blades.
Provide the specimen container in which the
sample is to be sent to the laboratory.
THE PROCEDURE

The sample is collected in either a plastic hat-type
receptacle, which is placed under the toilet seat, or in
a bedpan. It is important that the hat or bedpan be
clean and dry and that the sample not be contaminated with urine or water. Gloves are worn, and two
clean tongue blades are used to transfer the midportion of the sample to a clean, dry plastic container
with a tightly fitting lid. Any visible blood, mucus,
pus, or parasites should be included in the sample.
The container should be covered tightly as soon as
the sample is obtained.
The tongue blades should be double-wrapped in
paper towels, and they may be inserted into one of
the gloves when they are removed. The collection
container (e.g., plastic hat or bedpan) should be
thoroughly cleansed or disposed of, preferably in a
large plastic bag. Hands should be washed thoroughly.
In infants and young children, samples may be
obtained from diapers, provided that contact with
urine is avoided. To avoid contact, apply a urine
collection bag to catch the urine. Check the bag
frequently because the urine may spill and contaminate the feces.
The sample should be sent, properly labeled, to
the laboratory within 30 to 60 minutes. If this is not
possible, the sample may be refrigerated unless it is
to be tested for parasites, in which case it must be
sent to the laboratory while still warm.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after collection of a feces specimen include hand washing to prevent transmission
of pathogens to others and disposal of the articles
used according to standard precautions and transmission-based isolation procedures.
Diarrhea: Note and report frequency and gross
characteristics of bowel eliminations. Examine

Analysis

325

perianal area for irritation. Administer ordered
antidiarrheal or antibiotic therapy, or both.
Monitor for fluid deficit and replace fluid losses.
Cleanse perianal area after each episode of diarrhea and apply a soothing ointment. Inform client
that follow-up testing is conducted to evaluate
therapy, and instruct the client in the collection,
frequency, and transportation of specimens to the
laboratory. Report a positive result for parasites to
the physician immediately.

TESTS FOR SPECIFIC SUBSTANCES
IN FECES
Fecal samples can be chemically analyzed for a variety of substances including occult (hidden) blood,
qualitative fats, trypsin, urobilinogen, and bile. In
addition, estimates of carbohydrate utilization can
be made.
OCCULT BLOOD

The most frequently performed test of feces is chemical screening for occult blood. The purpose of the
test is to detect pathological lesions (e.g., carcinoma)
before they produce symptoms and while the condition is still amenable to treatment. Indeed, such testing is widely used in mass screening programs for
colorectal cancer, with 75 percent of such cancers
detected while still localized.15
A number of easy-to-use test kits for detection
of occult blood are available. Before the existence
of such kits, the traditional method was to expose
the sample to a sequence of solutions that included
glacial acetic acid, gum guaiac solution, and hydrogen peroxide. A blue color indicated a positive
test result. The test kits use these same principles,
with some using paper impregnated with guaiac.
For these reasons, analysis of feces for occult
blood is sometimes still referred to as a “stool for
guaiac.”
One of the main problems of testing stools for
occult blood is the number of false-positive results
that occur. A diet high in meat, for example, may
cause stools to test positive for blood, as do diets
high in certain vegetables (e.g., horseradish and
turnips) and bananas. In addition, bleeding from the
gums or nasal passages may produce positive results
for occult blood in stools. Therapy with many drugs
may lead to positive results because of direct or indirect drug effects on the gastrointestinal tract. These
drugs include aspirin (as little as one 300-mg tablet
per day), iron preparations, anticoagulants, adrenocorticosteroids, colchicine, and phenylbutazone. In
contrast, ascorbic acid may lead to false-negative
results.

326

SECTION I—Laboratory

TABLE 13–2
Condition

Tests

• Conditions Associated with Gastrointestinal Bleeding
Usual Age of Occurrence

Severity

Other Features

UPPER GI TRACT

Peptic ulcer
(gastric or
duodenal)

Any, including young
children

Variable, from
occult to lifethreatening

Pain, typical history often absent

Erosive gastritis

Usually adults over
age 25 yr

Usually mild; may
be very severe

Aspirin, alcohol use often predispose
Severe uremia, chronic liver disease
predispose

Atrophic gastritis

Adults over age 25 yr

Usually mild

Associated with pernicious anemia,
autoantibodies, decreased gastric
acidity

Esophageal
varices

Adults; children with
portal hypertension

Massive, sudden

Common in alcoholic liver disease
Cirrhosis or portal hypertension
always present

Mallory-Weiss
tears at gastroesophageal
junction

Any, but usually older
adults

Variable, depending on depth,
location of tear

Common in alcohol abusers

Hiatal hernia,
esophagitis

Progressively increasing incidence over
age 40 yr

Usually mild

Persistent, painless bleeding, a
common cause of iron-deficiency
anemia in elderly people

SMALL AND LARGE BOWEL

Meckel’s
diverticulum

Most common in children and young
adults

Moderate; stools
red or maroon

Caused by peptic ulceration of
ectopic gastric mucosa

Polyps

Any age

Usually mild; often
intermittent

Diarrhea, sometimes mucus in stools

Infections
diarrheas

Any age

Usually mild or
moderate

Ameba, Shigella, Clostridium difficile

Inflammatory
bowel disease
(Crohn’s disease,
ulcerative colitis)

Adolescents, adults
under age 60 yr

Usually mild but
may be massive

Diarrhea, pain, weight loss more
common in Crohn’s disease than in
ulcerative colitis
Bleeding more prominent in
ulcerative colitis

Diverticular
disease

Progressively increasing incidence over
age 40 yr

Usually mild,
frequently occult

Often asymptomatic, unless inflammation or abscess develops

Vascular
malformations

Older adults

Usually mild; may
be life-threatening in ~15%

Bleeding often recurrent

Often misdiagnosed as peptic ulcer
or diverticular disease

CHAPTER 13—Fecal

TABLE 13–2
Condition
Carcinoma

Analysis

327

• Conditions Associated With Gastrointestinal Bleeding
Usual Age of Occurrence
Older adults

Severity
Variable, from
occult to
moderate

Other Features
Common cause of iron-deficiency
anemia in older adults
Red blood more common with
distally located tumors

RECTUM AND ANUS

Hemorrhoids

Older adults

Usually mild; blood
is bright red

May be painless or symptomatic
Often associated with constipation

Anorectal fissure

Any age

Usually mild; blood
is bright red

Nearly always painful
Crohn’s disease, anal intercourse
may predispose

Adapted from Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 11. FA
Davis, Philadelphia, 2000, pp 985–986, with permission.

Numerous pathological conditions may cause
bleeding into the intestinal tract. Table 13–2 details
these disorders, including severity of bleeding and
other clinical features.
Sometimes bleeding appears so obvious that one
may be tempted not to confirm visual observations
with appropriate testing. Stools that are grossly red
or black are usually assumed to contain blood. Such
assumptions, however, must always be confirmed
because certain foods and medications may also
impart these colors to stools (see Table 13–1). If
blood is present in sufficient quantity, the color of
the stool reflects the source of the bleeding or the
length of time the blood was in the gastrointestinal
tract, or both. Black stools, for example, are associated with upper GI bleeding when the hemoglobin
has come in contact with gastric acid and has been
converted to acid hematin. In such cases, stools may
remain black for as long as 5 days after the initial
bleeding occurred. If, however, upper GI bleeding is
massive and the volume increases GI motility (e.g.,
as occurs in bleeding from esophageal varices),
stools may be red or maroon and somewhat liquid in
consistency. Generally, though, bright red stools are
associated with lower GI bleeding from hemorrhoids, ulcerative colitis, and carcinomas.16
For occult blood studies, samples are obtained
from rectal examination or portions of bowel movements. The client should follow a meat-free, highbulk diet for 3 days before testing and drugs that can
alter test results should be withheld. In practice,
however, these restrictions frequently are not
applied.

QUANTITATIVE FATS

As noted previously, the definitive test for excessive
fecal fat is the 72-hour quantitative measure, with
the amount of fat present expressed as a percentage
of solid material. Because fat output may vary on a
day-to-day basis, the 3-day collection is believed to
be the most reliable approach. In adults, a controlled
fat diet of 100 g per day also is followed during the
collection. In infants and children, for whom such a
diet could not be used, results of the collection are
based on the estimated intake of dietary fat. Thus, it
is important to know which foods were ingested
during the test period.17
TRYPSIN

Trypsin is an enzyme secreted by the pancreas. It is
normally not present in stools, except in children
under 2 years of age. If it is absent from the stools of
children under age 2 years, pancreatic deficiency is
indicated. Note that trypsin may not be detected if
the child is constipated, because of the prolonged
action of normal intestinal bacteria on the
enzyme.18
CARBOHYDRATE UTILIZATION

Individuals with various disorders related to malabsorption (e.g., celiac disease, tropical sprue, disorders involving the small intestine) may have
difficulty with carbohydrate absorption as well as fat
absorption. Thus, a thorough investigation of the
finding of steatorrhea (excess fat in the stool)
includes evaluation of carbohydrate metabolism.

328

SECTION I—Laboratory

Tests

Reference Values
Occult blood

Negative (0.5–2 mL/day)
5–7% of dietary intake
5 g/24 hr

Quantitative fat (72-hr collection)

10–25% of dry fecal matter
Neutral fat

1–5% of dry fecal matter

Fatty acids

5–15% of dry fecal matter

Trypsin

Positive (2 to 4)

Carbohydrates (Clinitest)

Negative

Urobilinogen
Random sample

Negative

24-hr collection

40–200 mg/24 hr
80–280 Ehrlich units/24 hr

Bile
Children

Positive

Adults

Negative

Such an evaluation includes performing oral and
intravenous (IV) glucose tolerance tests (see Chapter
5) and comparing the results. Persons with carbohydrate malabsorption have normal results on IV
glucose tolerance tests but not on oral glucose tolerance tests.19
If carbohydrates cannot be absorbed normally,
excessive amounts appear in the stool. This condition can be tested by placing a Clinitest tablet (Ames
Company, Elkhart, Indiana) in a portion of stool
that has been emulsified with water. Note that
Clinitest tablets are one of the methods used to
detect excess sugar in urine. When performed on
fecal samples, a positive Clinitest result indicates
carbohydrate malabsorption. This test is easily
performed and can be used as a screening test to
detect metabolic and intestinal disorders.
UROBILINOGEN

Urobilinogen is produced from bilirubin, a breakdown product of red blood cells, and normally
appears in urine (see Chapter 6) and feces. Because
blood and urine samples for products of bilirubin
metabolism are more easily obtained than stool
samples, this test is rarely used. Factors that may lead
to falsely decreased values include antibiotic therapy
and exposure of the sample to light.20

BILE

Bile should not be present in feces of adults because
it is broken down in the intestines during normal
digestion; however, tests for bile may normally be
positive in children. Bile may appear in the stools of
adults if there is rapid transit through the gastrointestinal tract (e.g., diarrhea). It may also be found in
clients with hemolytic anemias that produce jaundice.21
INTERFERING FACTORS

Ingestion of a diet high in meat, certain vegetables
(e.g., horseradish and turnips), and bananas can
cause false-positive results in tests for occult
blood.
Therapy with numerous medications can lead to
positive results in tests for occult blood because of
direct or indirect drug effects; examples of such
drugs are aspirin, anticoagulants, adrenocorticosteroids, iron preparations, colchicine, and
phenylbutazone.
Ingestion of ascorbic acid may lead to falsenegative results in tests for occult blood.
A diet too high or too low in fats or failure to
follow the prescribed diet (100 g of fat per day)
can alter results of quantitative fat tests.

CHAPTER 13—Fecal

Constipation can lead to false-negative results in
tests for fecal trypsin in children.
Ingestion of antibiotics and exposure of the fecal
sample to light can produce false-negative results
in tests for fecal urobilinogen.
INDICATIONS FOR TESTS FOR SPECIFIC
SUBSTANCES IN FECES

Occult Blood
Known or suspected disorder associated with
gastrointestinal bleeding (see Table 13–2)
Therapy with drugs that can lead to gastrointestinal bleeding (e.g., aspirin, anticoagulants)
Quantitative Fats
Suspected intestinal malabsorption or pancreatic
insufficiency as indicated by elevated fat levels
Monitoring of effectiveness of therapy for intestinal malabsorption or pancreatic insufficiency
Trypsin
Suspected pancreatic insufficiency in very young
children as indicated by negative or decreased
results
Carbohydrate Utilization (Clinitest)
Suspected malabsorption syndromes as indicated
by positive results
Urobilinogen
Suspected anemias characterized by decreased red
blood cell production as indicated by decreased
levels
Suspected liver and biliary tract disorders as indicated by decreased levels
Suspected hemolytic anemias as indicated by
increased levels
Bile
Suspected hemolytic anemias, which lead to
excessive levels
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
microscopic analysis of feces (see section under
“Microscopic Analysis of Feces”).
For tests for occult blood, the client should eat a
high-bulk, meat-free diet for 3 days before testing.
Medications that may alter test results (e.g.,
aspirin) may also be withheld for 3 or more days
before the test, although this practice should be
confirmed with the person ordering the study.
For qualitative fat studies, the client should follow
a diet containing 100 g of fat for 3 days before testing as well as during the test.
Alcohol, antacids, laxatives, and antibiotics may
also be withheld.

Analysis

329

The client should be provided with a large
container (usually a gallon paint can) and should
be instructed to refrigerate the sample.
If the test is for urobilinogen, the client should not
be taking antibiotics and should be supplied with
a light-protected container.
THE PROCEDURE

The procedure is essentially the same as that
described in the “Microscopic Analysis of Feces”
section. Fecal specimens for analysis of specific
substances are usually obtained on random samples,
although the test for quantitative fats requires a 72hour collection. Such a study is usually begun early
in the morning of a given day and continued for 3
consecutive days. The sample is maintained in a
large, refrigerated container (usually a gallon paint
can). Fecal studies for urobilinogen may be carried
out on a 24-hour basis.
When random samples are used, the tests are
often repeated on a serial basis, especially in studies
for occult blood. When this approach is used, it is
desirable to obtain the samples on 3 different days.
NURSING CARE AFTER THE PROCEDURE

Care and assessment are the same as for any fecal
specimen collection and analysis (see section under
“Microscopic Analysis of Feces”).
Instruct the client in sample collection procedures
according to the client’s ability to perform the
procedure.
Resume dietary and medication regimens after
the specimen is collected if they were modified to
prepare for the test.
Hemorrhage or anemia: Note and report blood
loss and characteristics; occult blood; pallor,
weakness, and other symptoms of anemia; and
possible site of blood loss. Administer ordered
whole blood or packed red blood cell transfusion.
Monitor vital signs and assist with care activities
to conserve energy.
Malabsorption syndromes: Note and report
presence of steatorrhea in feces and dietary intake
of fats and carbohydrates. Administer ordered
medications to treat pancreatic, liver, or biliary
disorders.

MICROBIOLOGIC TESTS OF FECES
STOOL CULTURES

Certain bacteria are normally found in feces (i.e., the
“normal flora” of the bowel). The presence of pathological types of bacteria may, however, produce diarrhea and other signs of systemic infection. Thus,

330

SECTION I—Laboratory

Tests
TABLE 13–3

Category
Osmotic

•

Types of Diarrhea

Specific Condition

Other Features

Disaccharidase deficiency (lactose
intolerance)

Symptoms follow ingestion of dairy
products.

Indigestible oligosaccharides in
beans, other legumes

Abdominal distention, “gas” very
common.

Saline laxatives

Patient may alternate constipation with
laxative abuse.
History of peptic ulcer symptoms.

Secretory

Nondigestible sugars in artificial
sweeteners

Dietary history is crucial.

Bacterial toxins (cholera, Escherichia
coli, staphylococcal food poisoning)

Epidemiology is more revealing than
stool culture.

Enteroactive hormones (gastrin in
Zollinger-Ellison syndrome; serotonin, others in carcinoid syndrome)

Other systemic symptoms are
common.

Malabsorption syndromes: fat, protein
Irritation by bile acids
Altered structure or
function

Intestinal resection

Follows ileal resection.
Bacterial overgrowth in small intestine.
Apparent from history.

Mucosal damage

Enterocolonic fistula

Complication of diverticular disease or
inflammatory bowel disease.

Irritable bowel syndrome

Pathophysiology remains unclear.

Inflammatory bowel disease (Crohn’s
disease, ulcerative colitis)

Bleeding, pain, weight loss may
accompany.

Invasive organisms (some shigella,
some salmonella, amebae,
campylobacter)

Stool cultures useful early in disease.

Pseudomembranous colitis

Often follows use of broad-spectrum
antibiotics.
May complicate uremia, antibiotic use,
congestive heart failure; intestinal
ischemia.

Adapted from Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 11 FA
Davis, Philadelphia, 2000, p 983, with permission.

most stool cultures are undertaken to evaluate diarrhea of unknown etiology to identify possible
causative bacteria. Bacteria produce diarrhea in
three main ways: (1) The organisms invade the
intestinal wall, damaging tissue; (2) the organisms
produce toxins within the intestine that alter
gastrointestinal motility; and (3) toxins produced by
bacteria are ingested (e.g., via foods) and produce
diarrhea, although the organisms themselves are not
detected in feces.22 Table 13–3 lists the types of diar-

rhea associated with specific conditions. The
primary purpose of stool cultures is to identify
organisms that cause damage to intestinal tissue.
Samples for stool cultures can be obtained either
by rectal swab or by collection of a bowel movement
sample. It is important that such samples not be
exposed to air or to room temperature more than
necessary, because these conditions can damage
bacteria so that they cannot be grown in culture.
Thus, samples obtained by rectal swab must be

CHAPTER 13—Fecal

placed in preservative, whereas those obtained from
bowel movements must be placed in tightly sealed
containers.
Reference Values
Stool culture

Normal flora

INTERFERING FACTORS

Therapy with antibiotics may decrease the type
and amount of bacteria present.
Excessive exposure of the sample to air or to room
temperature may damage bacteria so that they
will not grow in culture.
Failure to transport the sample to the laboratory
within 1 hour of collection may affect results.
INDICATIONS FOR STOOL CULTURES

Diarrhea of unknown etiology that may be caused
by bacteria that damage intestinal tissue (see Table
13–3)
NURSING CARE BEFORE THE PROCEDURE

Client preparation is essentially the same as that for
other tests of feces (see section under “Microscopic
Analysis of Feces”).
If the sample is to be obtained by rectal swab,
explain to the client how this will be accomplished.
THE PROCEDURE

If the sample is to be obtained by rectal swab, a clean
or sterile swab and preservative are needed.
Prepackaged sterile swabs with cylinders containing
preservative are commercially available for obtaining various types of samples for culture (e.g., wound
drainage, throat secretions). The swab is inserted
into the rectum (without the use of a lubricant) past
the anal sphincter. It is rotated gently and then withdrawn.23
For samples of portions of bowel movements, the
procedure is the same as that described in the
“Microscopic Analysis of Feces” section. The sample

Analysis

331

should be placed in a clean, dry container. Because
certain nonpathological bacteria are normally present in feces, it is not necessary for the container to be
sterile.
All samples should be protected from air and sent
to the laboratory within 1 hour of collection.
Samples should not be refrigerated.
NURSING CARE AFTER THE PROCEDURE

Care and assessment are the same as that for any
fecal specimen collection and analysis (see section
under “Microscopic Analysis of Feces”).
Assist or instruct client, or both, in collecting the
specimen, according to his or her ability to
perform the procedure.
Notify physician immediately of a positive culture
for pathogenic microorganisms.
REFERENCES
1. Hole, JW: Human Anatomy and Physiology, ed 4. Wm C Brown,
Dubuque, Iowa, 1987, pp 527–528.
2. Strasinger, SK: Urinalysis and Body Fluids, ed 4. FA Davis,
Philadelphia, 2001, p 205.
3. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, p 759.
4. Hole, op cit, p 528.
5. Sacher and McPherson, op cit, p 750.
6. Ibid, p 749.
7. Ibid, p 745.
8. Strasinger, op cit, p 208.
9. Kao, YS, and Liu, FJ: Malabsorption, diarrhea, and examination of
feces. In Henry, JB: Clinical Diagnosis and Management by
Laboratory Methods, ed 18. WB Saunders, Philadelphia, 1991, p
544.
10. Ibid, p 540.
11. Sacher and McPherson, op cit, p 755.
12. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 526.
13. Strasinger, op cit, p 206.
14. Kao and Liu, op cit, p 536.
15. Strasinger, op cit, p 208.
16. Sacher and McPherson, op cit, pp 756–757.
17. Kao and Liu, op cit, p 544.
18. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed 4.
JB Lippincott, Philadelphia, 1992, p 240.
19. Sacher and McPherson, op cit, p 758.
20. Nurse’s Reference Library, op cit, p 808.
21. Fischbach, op cit, p 240.
22. Sacher and McPherson, op cit, pp 751–752.
23. Nurse’s Reference Library, op cit, p 509.

Analysis of Cells
and Tissues
TESTS COVERED
Papanicolaou Smear, 333
Skin Biopsy, 335
Bone Biopsy, 335
Breast Biopsy, 336
Cervical Punch Biopsy, 337
Biopsy of Bladder/Ureter, 338
Renal Biopsy (Kidney Biopsy), 339
Chorionic Villus Biopsy, 341

Liver Biopsy, 342
Muscle Biopsy, 344
Lymph Node Biopsy, 344
Intestinal Biopsy (Small Intestine), 345
Lung Biopsy, 347
Pleural Biopsy, 348
Prostate Gland Biopsy, 349
Thyroid Gland Biopsy, 350

OVERVIEW OF CYTOLOGIC AND HISTOLOGICAL METHODS

The cells and
tissues of the body can be analyzed by means of cytologic and histological methods. Cytology
refers to the study of the structure, function, and pathology of cells. Histology deals with the
study of the structure, function, and pathology of tissues. Both methods are used primarily to
detect cancer.
Cytologic methods are used mainly as screening procedures to detect precancerous or malignant cells. Laboratory techniques were developed by George Papanicolaou, who identified
characteristics that allowed for differentiation of normal from neoplastic cells. This differentiation is based on changes that occur in the relationships between the cytoplasm and the nucleus
of cells.1 In performing cytologic examinations, slides with cells are stained with various
substances and then examined microscopically. Malignant cells may show large, darkly stained
irregular nuclei.2
The most common site examined through cytologic methods is the uterine cervix and
endometrium (site of the “Pap smear”). Cells from the respiratory tract are also frequently
examined. Samples of such cells can be obtained through sputum specimens (see Chapter 7),
from bronchial brushings or washings obtained during bronchoscopic examinations, or from
postbronchoscopy sputum specimens. Various body fluids can also be examined for abnormal
cells. Such fluids include urine (see Chapter 6); cerebrospinal fluid (see Chapter 8); and pleural, peritoneal, pericardial, and synovial effusions (see Chapter 9).
The method of reporting results of cytologic examinations varies somewhat with the
laboratory. Papanicolaou developed a numerical classification system for the various types of
cells found on cytologic examination. Because of problems with overlapping classes and variation in laboratory interpretation, narrative descriptions of the cells are now more likely to be
used.3

332

CHAPTER 14—Analysis

of Cells and Tissues

333

Note that cellular changes that mimic neoplastic changes can occur in response to inflammatory processes. Thus, the cytologist should be provided with information about the client so
that accurate interpretation of the cell types present can be made.4
In addition to its use in cancer detection, cytologic study may provide other types of diagnostic information. By examining cells obtained from the oral cavity, female sexual chromosomes (Barr bodies) can be identified. Various Papanicolaou stains can elicit cell types
associated with viral or fungal infections. Analysis of cells from effusions can also demonstrate
cell types associated with collagen vascular diseases such as systemic lupus erythematosus (SLE)
and rheumatoid arthritis. The nature of the cells present in vaginal smears can indicate the
client’s estrogen levels.5
Histological methods are used primarily to confirm the diagnosis of cancer when screening
tests are positive for abnormal cells. Histological techniques involve obtaining samples of tissue
by biopsy and examining them microscopically. Such an evaluation involves examining the
structure of the tissues and may also include cytologic study of the cells through the use of various staining techniques. Electron microscopy methods also have been used.6
If the tissue sample is that of a tumor, it is examined in relation to anatomic size, position,
and extent of the tumor. Whether malignant cells have invaded blood or lymphatic channels
also is assessed.7 Sections of tissue obtained at surgery may be frozen (i.e., “frozen sections”)
and analyzed during the surgical procedure to determine whether more extensive surgery is
needed, thus avoiding the client’s being subjected to a second procedure.
In addition to samples obtained during surgery, biopsies of tissues can be performed by local
excision, needle aspiration, or biopsy (Fig. 14–1) or with special instruments such as tissue
punches and curettes. Tissue samples can also be obtained during various endoscopic procedures (see Chapter 16). Common sites for biopsies are the skin, mucous membranes, serous
membranes (e.g., pleurae), synovial membranes that line the joints, various organs (e.g., liver,
kidney, lung), glands (e.g., thyroid, prostate), lymph nodes, bone, muscle, and female reproductive tissues. Bone marrow biopsies also are performed (see Chapter 1).

TESTS OF CELLS AND TISSUES
PAPANICOLAOU SMEAR

Figure 14–1. Types of biopsy needles: 1. Tru-Cut; 2.
Turner; 3. Franseen; 4. Shark Jaw.

The Papanicolaou (Pap) smear is used primarily in
the early detection of cervical cancer. Results of Pap
smears are reported in various ways, depending on
the laboratory’s preference. The traditional method
for reporting results is shown here:
Class I Normal cells only
Class II Atypical cells but not
malignant/inflammatory
Class III Atypical cells, suspicious of
malignancy/mild cervical dysplasia
Class IV Atypical cells, suggestive of
malignancy/severe cervical dysplasia
Class V Cancer cells present, conclusive for
malignancy/cancer
Abnormal results of Pap smears should be
followed by either repeat Pap smears or cervical
biopsies. It is recommended that women between
the ages of 20 and 40 years have a Pap smear at least

334

SECTION I—Laboratory

Tests

every 3 years. Women over age 40 years should have
a Pap smear every year. More frequent examinations
may be performed in women who are at high risk for
developing cervical cancer (e.g., positive family
history).
Reference Values
No abnormal cells (class I Pap smear)
INTERFERING FACTORS

Douching within 24 hours of the test, which may
wash away cells that would have been obtained on
sampling
Use of lubricating jelly on the vaginal speculum,
which may alter the sample
Improper specimen collection (Samples for
cancer screening are obtained from the posterior
vaginal fornix and from the cervix; samples for
hormonal evaluation are obtained from the
vagina.)
Improper preservation of the specimen upon
collection
Collection of the sample during menstruation;
blood in the sample may impair identification of
abnormal cells
INDICATIONS FOR PAPANICOLAOU SMEAR

Routine screening for cervical cancer
Evaluation of estrogen levels and response to therapy with estrogen
Identification of inflammatory tissue changes
Detection of viral and fungal vaginal infections
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test should not be performed when the
client is menstruating
That the client should not douche or have sexual
intercourse for at least 24 hours before the test
That, if client has been using antibiotic vaginal
medication, she should discontinue it and the test
should be delayed for 1 month
That all clothing below the waist must be
removed, except for the shoes, which may be kept
on (If the Pap smear is to be performed along with
a breast examination, it may be necessary to
remove all clothing and don an examination
gown.)
That the examination will be performed with the
client positioned on a gynecologic examination
table
That a metal or plastic vaginal speculum will be
inserted to visualize the cervix

That slight discomfort may be experienced when
the speculum is inserted
That relaxation and controlled breathing aid in
reducing discomfort during the examination
That samples of vaginal and cervical cells will be
obtained with a small wooden spatula or with a
cotton-topped applicator
That the examiner may perform a bimanual
examination involving the vagina, rectum, and
pelvic cavity as part of the examination
That a breast examination may also be performed
as part of the gynecologic evaluation
That the entire procedure should take approximately 15 minutes
Prepare for the procedure:
Ensure that the client voids immediately before
the examination.
Obtain a brief gynecologic history that includes
the date of the last menstrual period, frequency of
periods, duration of periods, type of menstrual
flow, date of last Pap smear, and use of birth
control pills or other medications containing
hormones.
THE PROCEDURE

The equipment needed is assembled, including
vaginal speculum, gloves, wooden spatulas or
cotton-tipped applicators, slides, preservative or
spray fixative, marking pens for labeling the samples,
and lubricant if a bimanual examination is to be
performed after the Pap smear has been obtained.
The client is positioned on the examination table.
The feet should not be placed in the stirrups until
immediately before the Pap smear is to be obtained.
When the feet have been positioned, the client
should be instructed to allow her legs to “drop” to
each side and to attempt to relax as much as possible. The client’s legs should be draped to avoid excessive and unnecessary exposure and chilling and to
reduce embarrassment.
The speculum may be dipped or rinsed in water
to aid in insertion but should not be lubricated.
With the speculum positioned, vaginal and cervical
samples are obtained and placed on slides. The slides
should be fixed with spray or placed in preservative
immediately.
The speculum is removed. If a bimanual pelvic
examination is to be performed, it takes place at this
time. However, a breast examination is usually
performed before obtaining the Pap smear.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client in removing the legs from the

CHAPTER 14—Analysis

stirrups and allowing the client to rest in a supine
position for a period of time.
Cleanse or allow client to cleanse excess lubricant
or secretions from the perineal area.
Provide a perineal pad if cervical bleeding occurs.
Follow-up examination: Note and report results
of the Pap smear, and advise client of the timing
and importance of the next examination. Explain
treatment of dysplasia if it is present.

SKIN BIOPSY
Skin biopsies are performed to detect malignancies
and are indicated when skin lesions have suspicious
appearance or when they change in size, color, or
texture. Skin biopsies can be performed with a
biopsy punch or by scraping or excising the lesion
using a scalpel.
Reference Values
No abnormal cells or tissue present
INDICATIONS FOR SKIN BIOPSY

Evaluation of skin lesions that are suspected of
malignancy
Diagnosis of keratoses, warts, moles, keloids,
fibromas, cysts, or inflammatory lesions
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test involves removing a small skin
sample or portion of a skin lesion
That the test will be performed by a physician
That it may be necessary to shave the site before
the biopsy
That a local anesthetic will be either sprayed onto
or injected at the biopsy site to prevent pain
That one or two sutures may be necessary to close
the biopsy site, depending on its extent
That a dressing or Band-Aid will be applied to the
site after the procedure

of Cells and Tissues

335

solution. A local anesthetic is applied by either topical spray or needle infiltration. Depending on the
size of the lesion to be biopsied, the area may be
draped with sterile drapes.
If the sample is to be obtained by curettage, the
surface of the lesion is scraped with a curette until
adequate tissue samples are obtained. The scrapings
are placed on a microscope slide and preserved with
an appropriate fixative. The sample is sent to the
laboratory immediately. If bleeding occurs, a BandAid is applied to the site.
If the sample is to be obtained by shave or excision, a scalpel is used to remove the portion of the
lesion that protrudes above the epidermis. Bleeding
is controlled with digital pressure. A sterile dressing
or Band-Aid is applied to the site. The sample is
placed in an appropriate fixative (usually in formalin) and sent to the laboratory immediately.
If the sample is to be obtained by punch biopsy, a
small round “cookie-cutter” punch, 4 to 6 mm in
diameter, is rotated into the skin to the desired
depth. The cylinder of skin is pulled upward with a
forceps and separated at its base with a pointed
scalpel or scissors. The site may then be closed using
sutures or other material, and a sterile dressing is
applied. The specimen is placed in an appropriate
fixative and sent to the laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
allowing the client to rest for a period of time, if
needed.
Assess dressing or Band-Aid for excessive bleeding.
Instruct client in care and assessment of the site.
Inform client of follow-up appointment to
remove sutures, if any are present.
Pain or infection, or both, at site: Note and
report excessive bleeding, redness, edema, or pain
at the biopsy site. Instruct the client to maintain a
dry and clean site until it is healed. Change dressing as needed. Administer ordered mild analgesic
and antibiotic therapy.

THE PROCEDURE

The equipment needed is assembled, including sterile drapes (depending on the site and the extent of
the lesion), materials for cleansing the skin, equipment for obtaining the sample, local anesthetic, jar
with formalin to preserve the specimen, suture or
other material to close the biopsy site, sterile gloves,
and dressings or Band-Aids.
The client is assisted to a position of comfort and
the area to be biopsied is adequately supported and
exposed. The area is then cleansed with antiseptic

BONE BIOPSY
A bone biopsy consists of removing a plug of bone
with a special serrated needle or surgically excising a
sample of bone for examination before further
surgery for bone disease. If performed by surgical
excision (i.e., “open” biopsy), the preparation and
procedure are the same as for any orthopedic surgical procedure requiring general anesthesia. Bone
biopsies are generally indicated when x-ray examination shows evidence of a lesion involving bone.

336

SECTION I—Laboratory

Tests

Reference Values
No abnormal cells or tissue present

INDICATIONS FOR BONE BIOPSY

Radiographic evidence of a bone lesion
Differentiation of benign from malignant bone
lesions
Identification of the source of a metastatic lesion
involving bone

The sample is placed in formalin and sent to the
laboratory immediately. The incision may be closed
with sutures or other material and a sterile dressing
applied.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for skin biopsy (see section under “Skin
Biopsy”).
After open biopsy, perform care in the same
manner as for anyone who has had surgery with
general anesthesia.

NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The method that will be used to obtain the sample
(needle biopsy or surgical excision)
That the procedure will be performed by a physician
That foods and fluids are usually not restricted
before a needle biopsy but are restricted before an
open biopsy
That special skin preparation may be required
(e.g., shave, orthopedic skin prep), especially for
an open biopsy
The type of anesthetic to be administered (local
infiltration for needle biopsies, general anesthesia
for open biopsies)
That, if a needle biopsy is to be performed,
momentary discomfort may be experienced when
the periosteum is penetrated
That a dressing will be applied to the site
That analgesics may be administered after the
procedure to alleviate any discomfort
Prepare for the procedure:
For an open biopsy, the physical preparation is the
same as for any surgical procedure requiring
general anesthesia. A shave or orthopedic skin
prep, or both, may be required before the procedure.
For a needle biopsy, a shave and orthopedic skin
prep may be required. The client should be
assisted to disrobe as necessary and should be
provided with a hospital gown.
THE PROCEDURE

For an open biopsy, the samples are obtained
through surgical excision during the operative
procedure.
For a needle biopsy, the client is assisted to a position of comfort, and the biopsy site is supported and
exposed. The skin is cleansed with an antiseptic
solution, injected with local anesthetic, and draped
with sterile drapes. A small incision is made, and the
biopsy needle is inserted to obtain a plug of bone.

BREAST BIOPSY
Breast lesions can be localized by palpation,
mammography, or ultrasound, but the nature of the
lesion can be confirmed only by biopsy. The tissue
sample can be obtained by needle aspiration or by
open incision. Many physicians perform only open
biopsies, excising the entire lesion rather than aspirating only a small sample.
A Mammotest is a more recently developed type
of breast biopsy performed for early detection and
diagnosis of breast malignancy. It is performed in
the x-ray department using a special instrument to
assist in obtaining a core biopsy (small amount of
tissue) of the breast. The site is anesthetized with a
local injection and a small incision is made to introduce the needle to obtain the biopsy. Several areas
can be biopsied if indicated. The method is considered to be as accurate as an open biopsy if the proper
protocol is followed.
Reference Values
No abnormal cells or tissue present
INDICATIONS FOR BREAST BIOPSY

Evidence of a breast lesion by palpation,
mammography, or ultrasound
Observable breast changes such as “peau d’orange” skin, scaly skin of nipple or areola, drainage
from nipple, or ulceration of skin
Differentiation of benign from malignant breast
lesions
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician
The method used to obtain the sample (needle
biopsy or surgical excision)
That foods and fluids are not usually restricted

CHAPTER 14—Analysis

before a needle biopsy but are restricted before an
open biopsy
The type of anesthetic to be administered (local
infiltration for a needle biopsy, general anesthesia
for an open biopsy)
That a dressing will be applied to the site
That analgesics may be administered after the
procedure to alleviate any discomfort
Prepare for the procedure:
For an open biopsy, the physical preparation is the
same as for any surgical procedure requiring
general anesthesia.
For a needle biopsy, the client should disrobe
from the waist up and should be provided with a
hospital gown with the opening in the front.
THE PROCEDURE

For an open biopsy, the sample is obtained
through surgical excision during the operative
procedure.
For a needle biopsy, the client is assisted to a
supine position and the area to be biopsied is
exposed. The skin is cleansed with antiseptic,
injected with local anesthetic, and draped with sterile drapes. A needle (either a Vim-Silverman biopsy
needle or an 18-gauge needle) is inserted into the
mass. A plug of tissue or bolus of fluid is aspirated
via a syringe connected to the needle. The tissue is
placed in a specimen container with normal saline;
fluid is gently expelled into a green-topped
(heparinized) blood collection tube. The samples
should be sent to the laboratory immediately. A sterile dressing is applied to the biopsy site.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for skin biopsy (see section under “Skin
Biopsy”).
After an open biopsy, perform care in the same
manner as for anyone who has had surgery with
general anesthesia.
Pain or infection: Note and report degree of pain
after the procedure. Apply an ice bag to the site.
Inform client to assess for and report redness,
edema, or drainage at the biopsy site. Advise client
to wear a bra with good support 24 hr/day after
the procedure until healing is complete. Administer ordered analgesic and antibiotic therapy.
Breast self-examination: Instruct client to perform monthly breast self-examination (BSE)
and to have a mammogram done annually to
ensure early detection of breast malignancy. Offer
literature from the American Cancer Society
about the prevention and treatment of breast
pathology.

of Cells and Tissues

337

CERVICAL PUNCH BIOPSY
Punch biopsy of the uterine cervix may be
performed during a routine pelvic examination if
abnormal areas are noted, or it may be indicated by
abnormal results of a Pap smear (see earlier section)
or a positive Schiller test. The Schiller test involves
applying iodine solution to the cervix. Normal
tissues stain dark brown, but abnormal tissues fail to
pick up the color. Both the Schiller test and punch
biopsy of the cervix are performed using a colposcope, a specialized binocular microscope that
allows direct visualization of the cervix. Punch
biopsy results may indicate the need for the more
extensive cone biopsy of the cervix. This operative
procedure involves excision of cervical tissue and
requires general anesthesia.
Reference Values
No abnormal cells or tissue present

INDICATIONS FOR CERVICAL PUNCH BIOPSY

Abnormal Pap smear
Schiller test positive for abnormal cells or tissue
Appearance of abnormal cells or tissue (e.g.,
ulceration, leukoplakia, polyps) on colposcopic
examination
Differentiation of benign from malignant cells or
tissue
CONTRAINDICATIONS

Acute pelvic inflammatory disease
Cervicitis
Bleeding disorder
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test should not be performed when the
client is menstruating and is best performed
approximately 1 week after her period has ended
That all clothing below the waist needs to be
removed, except for the shoes, which may be kept
on
That the procedure will be performed with the
client positioned on a gynecologic examination
table
That a metal or plastic vaginal speculum will be
inserted to visualize the cervix
That slight discomfort may be experienced when
the speculum is inserted
That relaxation and controlled breathing aid in
reducing discomfort during the examination
That the cervix may be swabbed with iodine to aid

338

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in identification of abnormal cells (If the client is
allergic to iodine, it should be noted before the
test.)
That a microscope-like device will be used to
more clearly visualize the cervix but that it is not
inserted into the vagina
That a small sample of cervical tissue will be
obtained with forceps
That mild discomfort may be experienced when
the sample is removed as well as after the test
That the entire procedure should take approximately 15 minutes
That a small amount of cervical bleeding may
occur after the procedure
That a gray-green vaginal discharge may persist
for a few days to a few weeks after the procedure
That strenuous exercise should be avoided for 8 to
24 hours after the procedure
That douching and intercourse should be avoided
for approximately 2 weeks after the procedure or
as directed by the physician
Prepare for the procedure:
Ensure that the client voids immediately before
the procedure.

Assist client in cleansing excess lubricant, solutions, or secretions from the perineal area and in
dressing, if needed.
Inform the client that she should remove the vaginal tampon in 8 to 24 hours and wear a pad if
bleeding or drainage is present.
Remind the client that a gray-green vaginal
discharge can persist for a few days to a few weeks
and that strenuous activity should be avoided for
8 to 24 hours and douching and intercourse for 2
weeks or as otherwise directed by the physician.8
Hemorrhage: Note and report excessive and
prolonged vaginal bleeding after the removal of
the tampon. Instruct the client to assess for and
report excessive bleeding.

BIOPSY OF BLADDER/URETER
Biopsies of the bladder and ureter are usually
performed during cystoscopic examinations of the
bladder. Such biopsies are indicated if a bladder
tumor is visualized radiologically, if the symptoms
persist after excision of bladder polyps or tumors,
and if a hydroureter without kidney stones is
evident.

THE PROCEDURE

The client is positioned on the examination table.
The legs are draped and the external genitalia
cleansed with an antiseptic solution. The vaginal
speculum is inserted using water as a lubricant if a
Pap smear is to be performed before the biopsy.
For the biopsy, the cervix is swabbed with 3
percent acetic acid to remove mucus and improve
the contrast between tissue types. If the Schiller test
is to be performed, the cervix is swabbed with iodine
solution to aid in identification of abnormal cells.
The colposcope is inserted through the speculum
and is focused on the cervix. If an area is identified
as abnormal, the biopsy forceps are inserted through
the speculum or colposcope, and tissue samples are
obtained. The samples are placed in specimen
containers with formalin solution. The containers
should be labeled with the source of the samples.
Bleeding, which is not uncommon after a cervical
punch biopsy, can be controlled by cautery or suturing or by applying silver nitrate or ferric subsulfate
to the site. If bleeding persists, a tampon may be
inserted by the physician after removal of the speculum.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to remove the legs from the stirrups and allowing the client to rest for a period of
time.

Reference Values
No abnormal cells or tissue present
INDICATIONS FOR BIOPSY OF BLADDER/URETER

Differentiation between benign and malignant
lesions involving the bladder or ureter, or both,
especially if bladder tumor is evident on radiologic examination or if hydroureter is present
without stones
Monitoring of recurrent lesions of the bladder or
ureter for malignant changes
CONTRAINDICATIONS

Acute cystitis
Bleeding disorders
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a urologist during a cystoscopic examination of the bladder
That a sedative may be administered before the
procedure to promote relaxation
The type of anesthetic to be administered (local
or general anesthesia may be used)
That, if general anesthesia is to be used, foods and
fluids are withheld for 8 hours before the procedure

CHAPTER 14—Analysis

That, if local anesthesia is to be used, only clear
liquids may be taken for 8 hours before the test
That the test will be performed with the client
positioned on a special urologic table and that the
legs will be elevated in stirrups
That after he or she is positioned on the table, the
legs will be draped and the external genitalia will
be cleansed with antiseptic solution
That a special microscope-like instrument will be
inserted into the urethra to visualize the bladder
That, if local anesthesia is used, a sensation of
pressure or of having to void, or both sensations,
may be experienced
That a small amount of tissue will be removed
from the bladder or ureter, or from both, with a
special brush or forceps inserted through the
cystoscope
That, after tissue removal and inspection of the
bladder and urethra, the cystoscope will be
removed
That vital signs and urinary output will be monitored closely after the test
That burning or discomfort on urination may be
experienced for the first few voidings after the test
That urine may be blood tinged for the first and
second voidings after the test
Prepare for the procedure:
Assist the client to disrobe from at least the waist
down and provide a hospital gown, if necessary.
Ensure to the extent possible that dietary or fluid
restrictions, or both, are followed before the test.
If general anesthesia is to be used, the physical
preparation is the same as for any surgical procedure requiring general anesthesia.
If local anesthesia is to be used, the client’s vital
signs are checked and premedication is administered as ordered.
THE PROCEDURE

The client is positioned on the examination table,
and the legs are placed in the stirrups and draped. If
general anesthesia is to be used, it is administered
before positioning the client on the table. The external genitalia are cleansed with antiseptic solution. If
a local anesthetic is to be used, it is instilled into the
urethra and retained for 5 to 10 minutes. A penile
clamp may be used for male clients to aid in retention of the anesthetic.
The cystoscope alone may be used for the examination or a urethroscope may be used to examine
the urethra before cystoscopy. The urethroscope has
a sheath that can be left in place and the cystoscope
can be inserted through it, thus avoiding multiple
instrumentations. After the cystoscope is inserted,
the bladder is irrigated and then inspected. Urine

of Cells and Tissues

339

samples may be obtained before bladder irrigation.
The area of the bladder to be biopsied is identified
and tissues are removed by cytology brush or biopsy
forceps. If a tumor is found and if it is small and
localized, it may be excised. Bleeding can be
controlled using electrocautery. If ureteral samples
are needed, small catheters can be inserted into the
ureters via the cystoscope. Specimens obtained for
biopsy are placed in appropriate containers and sent
to the laboratory immediately.
On completion of cystoscopy and collection of
tissue samples, the cystoscope is withdrawn. The
client’s legs are removed from the stirrups, and the
supine position is assumed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for skin biopsy (see section under “Skin
Biopsy”).
If local anesthesia was used, monitor vital signs
and compare with baseline values.
If general anesthesia was used, perform care in the
same manner as for anyone who has had this type
of anesthesia. Resume food and fluid withheld
before the procedure. Encourage a fluid intake of
3000 mL per 24 hours unless contraindicated.
Hemorrhage: Note and report change in vital
signs or hematuria, or both, after the second voiding. Collect and send urine specimen to the laboratory. Test urine for occult blood with dipstick.
Monitor intake and output (I&O) for 24 hours.
Urinary pattern changes: Note and report
resumption of normal voiding pattern, time and
amount of voidings as well as urine characteristics, bladder distention, incomplete emptying of
the bladder, suprapubic or flank pain, chills, fever,
or bladder spasms. Administer ordered analgesic
and warm sitz or hip baths to alleviate discomfort.
Administer prophylactic antibiotic therapy, if
ordered. Instruct client in monitoring urinary
output and instruct to report pain, chills, bleeding, and fever to physician if client is an outpatient.

RENAL BIOPSY (KIDNEY BIOPSY)
Renal biopsy involves obtaining a sample of kidney
tissue for histological and cytologic evaluation. The
test may be performed by percutaneous needle
biopsy (closed biopsy) or through surgical incision
(open biopsy). Lesions of the kidney can be localized
by renal computed axial tomography (CAT) scan or
ultrasound.
Renal biopsy, especially when performed by the
percutaneous method, is not without its attendant

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Tests

risks. Bleeding within the kidney, damage to
renal tissue, and infection may occur. Therefore,
this procedure is performed only when absolutely
necessary to obtain data not otherwise available
through blood, urine, and noninvasive radiologic
tests.
Reference Values
No abnormal cells or tissue present
INDICATIONS FOR RENAL BIOPSY
(KIDNEY BIOPSY)

Determination of the nature of lesions of the
kidney identified by renal CAT scan or ultrasound
(e.g., benign versus malignant lesions)
Hematuria, proteinuria, or urinary casts, or a
combination of these conditions, of unknown
etiology, to determine the nature of the renal
disorder
Monitoring of the progression of nephrotic
syndrome
Acute or rapidly progressing renal failure of
unknown etiology
Systemic lupus erythematosus (SLE) with urinary
abnormalities, to determine the extent of renal
involvement
Suspected renal cysts to confirm the diagnosis
Monitoring of the function of a transplanted
kidney
CONTRAINDICATIONS

Bleeding disorders
Advanced renal disease with uremia
Severe, uncontrolled hypertension
Solitary kidney (except transplanted kidney)
Gross obesity and severe spinal deformity
(contraindicates percutaneous needle biopsy)
Inability of the client to cooperate during the
procedure (contraindicates percutaneous needle
biopsy)
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician
The method that will be used to obtain the sample
(percutaneous [closed] biopsy or surgical [open]
biopsy)
The type of anesthesia to be administered (local
infiltration for needle biopsies, general anesthesia
for open biopsies)
That foods and fluids are withheld for 6 to 8 hours
before the procedure

Nursing Alert

Renal biopsy, especially when performed by
the percutaneous method, may result in
bleeding within the kidney, damage to renal
tissue, and infection.
Before the procedure the client’s hematologic
status and blood clotting ability must be
assessed; therefore, a complete blood count
(CBC), platelet level, prothrombin time (PT),
partial thromboplastin time (PTT), clotting
time, and bleeding time should be performed
before the test. (In addition, a type and crossmatch for 2 units of blood may be ordered.)
After the procedure, the client’s vital signs,
amount of urine output, characteristics of
urine output, and comfort level must be
monitored closely for early detection of possible complications.

That a sedative may be administered before the
procedure
That, if a needle biopsy is performed, it will be
necessary to remain motionless and breathe as
instructed during certain portions of the procedure
That, if a needle biopsy is performed, a pressure
dressing will be applied to the site
That, after a needle biopsy, the client will be
required to lie on the biopsied side for at least 30
minutes, with a pillow or a sandbag under the site
to prevent bleeding
That bed rest is required for 24 hours after the
procedure
That vital signs and urinary output will be monitored closely for at least 24 hours after the test
That, unless medically contraindicated, the client
should have a fluid intake of approximately 3 qt
(3000 mL) for at least the first 24 hours after the
test
That strenuous activity, sports, and heavy lifting
should be avoided for at least 2 weeks after the test
That any discomfort, especially in the area of the
kidneys, shoulders, or abdomen, should be
reported immediately
Prepare for the procedure:
Ensure that a signed consent for the procedure
has been obtained.
If the skin at the biopsy site is unusually hirsute, it
may be necessary to shave the site before the
procedure.
Ensure to the extent possible that dietary and
fluid restrictions are followed before the test.

CHAPTER 14—Analysis

If an open biopsy is to be performed, the physical
preparation is the same as for any surgical procedure requiring general anesthesia.
For a percutaneous needle biopsy, the client’s vital
signs are taken and compared with baseline levels.
The client should void immediately before the
procedure and be provided with a hospital gown.
(The premedication, if ordered, is administered
30 to 60 minutes before the procedure.)
THE PROCEDURE

For an open biopsy, the samples are collected during
the operative procedure.
For a percutaneous needle biopsy, the client is
assisted to the prone position. A sandbag may be
placed beneath the abdomen to aid in moving the
kidneys to the posterior and in maintaining the
desired position. The biopsy site is exposed, cleansed
with antiseptic, and draped with sterile drapes. The
skin and subcutaneous tissues are then infiltrated
with a local anesthetic.
To facilitate downward movement and subsequent immobilization of the kidneys, the client is
instructed to take a deep breath and hold it as the
biopsy needle (usually a Vim-Silverman needle) is
inserted. As the needle enters the kidney, the client is
instructed to exhale. The needle is rotated to obtain
a plug of tissue and then withdrawn. Manual pressure is applied to the site for 5 to 20 minutes. If there
is no evidence of bleeding, a pressure dressing is
applied. The tissue sample is placed in a container
with buffered saline and sent immediately to the
laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after an open biopsy are the
same as for anyone who has had surgery requiring
general anesthesia.
For a percutaneous biopsy, place the client on the
biopsied side and maintain the position with a
small pillow or sandbag under the biopsy site for
at least 30 minutes.
Maintain complete bed rest for 24 hours after the
test.
Resume foods and fluids withheld before the test.
Unless medically contraindicated, encourage the
client to take in 3000 mL of fluid during the first
24 hours after the procedure.
Collect a urine specimen for culture and sensitivity 24 hours after the test.
Remind client that heavy lifting or any strenuous
activities should be avoided for 1 week after the
procedure.
Take and record vital signs as for a postoperative
client whether the biopsy was performed by open

of Cells and Tissues

341

or closed technique (i.e., every 15 minutes for the
first hour, every 30 minutes for the next 2 hours,
every hour for the next 4 hours, and then every 4
hours for 24 hours).
Assess the biopsy site for bleeding, hematoma
formation, and inflammation each time vital signs
are taken.
Assess the client’s comfort level, and report immediately any complaints of perirenal, shoulder, or
abdominal pain.
Monitor time and amount of each voiding.
Assess each voiding for the presence of blood.
This assessment may involve using dipsticks to
detect microscopic blood. Report immediately
any grossly bloody urine.
Monitor temperature for several days and instruct
client to report burning and frequency of urination or any other change in urinary pattern.

CHORIONIC VILLUS BIOPSY
Chorionic villus biopsy (CVB) is used to detect fetal
abnormalities caused by various genetic disorders.
The advantage of CVB over amniocentesis (see
Chapter 10) is that CVB can be performed as early as
the eighth week of pregnancy, thus permitting earlier
decisions to retain or terminate the pregnancy.
Chorionic villi are fingerlike projections that
cover the embryo and anchor it to the uterine lining
before development of the placenta. Because chorionic villi are of embryonic origin, samples provide
information about the developing baby. Chorionic
villi samples are best obtained between the 8th and
10th weeks of pregnancy. After 10 weeks of pregnancy, the villi are overgrown with maternal cells.
CVB can be used to detect hundreds, and potentially even thousands, of genetic defects. It cannot,
however, be used to detect neural tube defects such
as spina bifida. For the latter condition, amniocentesis is still the test of choice.
CVB is performed in a manner similar to an
amniocentesis, although entry into the amniotic sac
is not necessary. The test carries with it the risks of
damage to the chorionic membrane, bleeding, and
possible spontaneous abortion even as late as 18 to
20 weeks of pregnancy. The number of spontaneous
abortions attributed to CVB is estimated to be as low
as 2 percent.9
In addition to the CVB’s advantage of being
performed earlier than amniocentesis, results are
also available more quickly—many times within 48
hours of the study.
The developing embryo and chorion can be localized before or during the procedure by ultrasound
or endoscopic tests.

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SECTION I—Laboratory

Tests

Reference Values
No chromosomal abnormalities detected
INDICATIONS FOR CHORIONIC VILLUS BIOPSY

Family history of genetic disorders (e.g., chromosomal abnormalities, enzyme deficiencies, sickle
cell anemia or other hemoglobinopathies, TaySachs disease)
Maternal age over 35 years to screen for disorders
such as Down syndrome
Prenatal gender determination when the woman
is a known carrier of a sex-linked disorder such as
hemophilia
Need for early decision to terminate or maintain pregnancy when fetal abnormality is
suspected
CONTRAINDICATIONS

History of incompetent cervix
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician and requires approximately 15 minutes
The precautions taken to avoid injury to the
fetus (e.g., localization of the embryo by ultrasound)
That all clothing below the waist must be
removed, except for the shoes, which may be kept
on
That the procedure will be performed with the
client positioned on a gynecologic examination
table
That a metal or plastic vaginal speculum will be
inserted to visualize the cervix
That slight discomfort may be experienced when
the speculum is inserted
That relaxation and controlled breathing aid in
reducing discomfort during the examination
That a small catheter will be inserted through the
cervix to a site between the wall of the uterus and
the developing embryo
That a small amount of tissue will be removed by
gentle suction
That the suction catheter and speculum will then
be removed
Prepare for the procedure:
Ensure that the client voids immediately before
the procedure.
Take and record vital signs and compare with
baseline readings.
Obtain history of genetic disorders and counseling received.

THE PROCEDURE

The client is positioned on the examination table.
The legs are draped, and the external genitalia may
be cleansed with an antiseptic solution. The vaginal
speculum is then inserted. For the biopsy, a suction
catheter is inserted via the speculum through the
cervical os to the biopsy site. The catheter is then
connected to a 20-mL syringe, and approximately 10
mL of suction is applied. The suction is maintained
as the catheter is withdrawn to avoid introducing
cervical secretions into the uterus. The outside of the
catheter is wiped to remove maternal secretions, and
the tissue sample is flushed onto Petri dishes with an
appropriate culture medium. The samples are
labeled and sent to the laboratory immediately to be
examined for chromosomal abnormalities.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for cervical biopsy (see section under
“Cervical Punch Biopsy”).
Abnormal results: If appropriate and timely, offer
information about genetic counseling or pregnancy termination counseling, or both.
Hemorrhage or infection, or both: Note and
report vital sign and fetal heart rate changes,
abdominal pain, temperature and chills, or excessive vaginal bleeding. Inform the client to monitor
and report these changes to the physician.

LIVER BIOPSY
Liver biopsy involves obtaining a sample of hepatic
tissue for histological and cytologic evaluation. The
test may be performed by percutaneous needle
biopsy (closed biopsy) or through surgical incision
(open biopsy). This test is indicated when liver
disease is suspected but is not evidenced by less invasive procedures such as ultrasounds and CAT scans.
Liver biopsy, especially when performed by the
percutaneous method, is not without its attendant
risks: Bleeding within the liver, damage to hepatic
tissue, and infection may occur. Therefore, this
procedure is performed only when absolutely necessary.
Reference Values
No abnormal cells or tissue present

INDICATIONS FOR LIVER BIOPSY

Suspected disease of the liver parenchyma
(e.g., cirrhosis, malignancy, hemochromatosis,

CHAPTER 14—Analysis

sarcoidosis, hepatitis, amyloidosis) to determine
nature of the pathological problem
Hepatomegaly (enlarged liver) or jaundice of
unknown etiology
Persistently elevated liver enzymes of unknown
etiology
CONTRAINDICATIONS

Bleeding disorders
Suspected vascular tumor of the liver
Ascites, which may obscure location of the liver
for percutaneous biopsy
Subdiaphragmatic or right hemothoracic infection
Infection involving the biliary tract
Inability of the client to cooperate during the
procedure (contraindicates percutaneous needle
biopsy)
Nursing Alert

Liver biopsy, especially when performed by
the percutaneous route, can result in bleeding
within the liver, damage to hepatic tissue, and
infection.
Clients with liver disease frequently have
impaired blood coagulation and are especially
at risk for bleeding during or after this procedure.
Before the procedure, the client’s hematologic
status and blood clotting ability must be
assessed; therefore, a CBC, platelet level, PT,
PTT, clotting time, and bleeding time should
be performed before the study.
After the procedure, the client’s vital signs
must be monitored closely; in addition, the
client’s comfort level must be assessed.
Complaints of right shoulder or pleuritic
chest pain should be reported immediately.
(Respiratory distress caused by bleeding
within the liver or inadvertent pneumothorax
may also occur.)
NURSING CARE BEFORE THE PROCEDURE

of Cells and Tissues

343

That foods and fluids are withheld for 6 to 8 hours
before the procedure
That if a needle biopsy is performed, it will be
necessary to remain motionless and breathe as
instructed during certain portions of the procedure (Allow client to practice holding the breath
after an expiration.)
That if a needle biopsy is performed, the client
may experience slight discomfort in the area of
the right shoulder when the biopsy needle is
introduced
That if a needle biopsy is performed, a pressure
dressing will be applied to the site
That after a needle biopsy, the client must lie on
the right side with a rolled towel or small pillow
under the site to create pressure and prevent
bleeding and that this position must be maintained for at least 2 hours
That bed rest is required for 24 hours after the
procedure
That vital signs will be monitored closely for at
least 24 hours after the test
That any unusual or persistent discomfort or any
difficulty breathing should be reported immediately
Prepare for the procedure:
Ensure that a signed consent for the procedure
has been obtained.
If the skin at the biopsy site is unusually hirsute, it
may be necessary to shave the site before the
procedure.
If an open biopsy is to be performed, the physical
preparation is the same as for any surgical procedure requiring general anesthesia.
For a percutaneous needle biopsy, the client’s vital
signs are taken and compared with baseline readings. The client should void immediately before
the procedure and be provided with a hospital
gown.
Administer a sedative, if necessary, as ordered.
THE PROCEDURE

For an open biopsy, the samples are collected during
the operative procedure.
For a percutaneous needle biopsy, the client is
assisted to the supine or the left lateral position with
the right hand under the head. The biopsy site is
exposed, cleansed with antiseptic, and draped with
sterile drapes. The skin and subcutaneous tissues are
then infiltrated with a local anesthetic. The syringe is
attached to the biopsy needle. The client is then
instructed to take a deep breath, exhale forcefully,
and hold his or her breath. The biopsy needle is
then inserted, rotated to obtain a core of liver tissue,
and quickly removed. It is important that the client

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Tests

remain motionless during biopsy needle insertion.
After the needle is removed, the client may resume
normal breathing. A pressure dressing is applied to
the site. The sample is expelled from the needle into
a container with formalin solution and sent to the
laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after an open biopsy include
care in the same manner as for anyone who has had
surgery requiring general anesthesia.
For a percutaneous biopsy, position client on the
right side with a rolled towel or small pillow
under the biopsy site to create pressure and
prevent bleeding.
Maintain this position for at least 2 hours.
Maintain complete bed rest for 24 hours after the
test.
Resume foods and fluids withheld for the test.
If ordered, administer analgesics for postbiopsy
discomfort.
Advise the client not to cough or strain after the
procedure because it can increase intra-abdominal pressure.
Take and record vital signs as for a postoperative
client, whether the biopsy was performed by open
or closed technique (i.e., every 15 minutes for the
first hour, every 30 minutes for the next 2 hours,
every hour for the next 4 hours, and then every
4 hours for 24 hours).
Assess the biopsy site for bleeding, hematoma
formation, bile leakage, and inflammation each
time vital signs are taken.
Assess the client’s comfort level and immediately
report pleuritic pain, persistent right shoulder
pain, or abdominal pain.
Assess the client’s respiratory status and immediately report any signs or symptoms of respiratory
distress.

MUSCLE BIOPSY
A muscle biopsy consists of obtaining a sample of
tissue, usually from the deltoid or gastrocnemius
muscle, for histological study. Muscle biopsies are
indicated for suspected neuropathy or myopathy.

Neuromuscular disorders of unknown etiology to
differentiate between neuropathy and myopathy
INTERFERING FACTORS

Electromyography, if performed before muscle
biopsy, may produce residual inflammation leading to false-positive biopsy findings.
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician and requires approximately 15 minutes
The site from which the sample will be obtained
(usually the deltoid or gastrocnemius muscle)
That it may be necessary to shave the biopsy site
before the study
That the procedure involves making a small incision over the muscle and removing a small bit of
muscle tissue with a biopsy forceps
That a local anesthetic will be injected at the
biopsy site to alleviate discomfort
That suture or other material may be necessary to
close the biopsy site
That a dressing will be applied to the biopsy site
That the muscle will be tender to touch and
movement for several days after the procedure
That, if the area to be biopsied is hirsute, it may be
necessary to shave it before the biopsy
THE PROCEDURE

The client is assisted to the necessary position
(supine for deltoid biopsy, prone for gastrocnemius
biopsy). The biopsy site is exposed, cleansed with
antiseptic, and draped with sterile drapes. The skin
and subcutaneous tissues are then infiltrated with a
local anesthetic. A small incision is made over the
muscle with a scalpel, and a bit of muscle tissue is
then grasped with a forceps and excised. The sample
is placed in normal saline and sent to the laboratory
immediately. The incision is closed with sutures or
other material, and a sterile dressing is applied.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for skin biopsy (see section under “Skin
Biopsy”).

Reference Values
No abnormal cells or tissue present
INDICATIONS FOR MUSCLE BIOPSY

Family history of Duchenne’s muscular dystrophy
Diagnosis of suspected fungal or parasitic infestation of muscle

LYMPH NODE BIOPSY
Lymph node biopsies are performed when there is
persistent enlargement of lymph nodes or signs and
symptoms of systemic disease that may indicate
malignant or infectious processes. The lymph nodes
most commonly biopsied are the cervical, axillary,
and inguinal nodes. Cervical lymph nodes drain the

CHAPTER 14—Analysis

scalp and face; axillary lymph nodes drain the arms,
breasts, and upper chest; and inguinal nodes drain
the legs, external genitalia, and lower abdominal
wall.
Lymph node biopsies may be performed by
needle aspiration or by surgical excision. The latter
approach is preferred when the node is deeper and
when a larger or more complete sample of the node
is required.
Reference Values
No abnormal cells or tissue present

INDICATIONS FOR LYMPH NODE BIOPSY

Persistent enlargement of one or more lymph
nodes of unknown etiology, especially if accompanied by signs of systemic illness such as weight
loss, fever, night sweats, cough, edema, and pain
Differentiation between benign (e.g., sarcoidosis)
and malignant (e.g., lymphomas, leukemias)
disorders that can lead to enlarged lymph nodes
Suspected fungal or parasitic infections involving
the lymph nodes
Staging of metastatic carcinomas, with the stage
indicated by the extent of lymph node involvement
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The method that will be used to obtain the sample
(needle biopsy or surgical excision)
That foods and fluids are usually not restricted
before a needle biopsy but are restricted before an
excisional biopsy
That the procedure will be performed by a physician
The type of anesthesia to be administered (local
infiltration for needle biopsies, general anesthesia
for excisional biopsies if deeper nodes are to be
removed)
That, if an excisional biopsy is performed, sutures
or other material may be used to close the biopsy
site
That a dressing will be applied to the biopsy site
That analgesics may be administered after the
procedure to alleviate any discomfort
That if the skin at the biopsy site is unusually
hirsute, it may be necessary to shave the site before
the procedure
Prepare for the procedure:
Take and record vital signs and compare with
baseline readings.
Provide a hospital gown.

of Cells and Tissues

345

THE PROCEDURE

The site to be biopsied is exposed, cleansed with
antiseptic, and draped with sterile drapes. If the
biopsy is to be performed under local anesthesia, the
skin and subcutaneous tissues are so infiltrated.
For surgical excision of the node, a small incision
is made over the node. The lymph node is then
grasped with forceps and placed in normal saline
solution. The biopsy site is closed with sutures or
other materials and a sterile dressing is applied.
For a needle biopsy, the lymph node is grasped
with the fingers and a needle with syringe attached is
inserted directly into the node. A specimen is then
aspirated and placed in a container with normal
saline solution. Pressure is applied to the site. If there
is no bleeding, a sterile dressing is applied.
All specimens are sent to the laboratory immediately.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for skin biopsy (see section under “Skin
Biopsy”).
If general anesthesia was used, care is the same as
for anyone who has had this type of anesthetic.
Administer ordered analgesic therapy, if needed.

INTESTINAL BIOPSY (SMALL INTESTINE)
Biopsies of the small intestine are generally
performed during endoscopic procedures. During
these tests, samples of intestinal tissue can be
obtained via the endoscope if abnormal lesions are
visualized.
Reference Values
No abnormal cells or tissue present
INDICATIONS FOR INTESTINAL BIOPSY
(SMALL INTESTINE)

Suspected malignant or premalignant tissue
change on endoscopic visualization
Differentiation between benign and malignant
disorders involving the small intestine
Diagnosis of various intestinal disorders such as
lactose intolerance, enzyme deficiencies, sprue,
and parasitic infestations
INTERFERING FACTORS

Barium swallow within the preceding 48 hours
CONTRAINDICATIONS

Aneurysm of the aortic arch

346

SECTION I—Laboratory

Tests

Inability of the client to cooperate during the
procedure
Bleeding disorders
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed during an
endoscopic examination of the stomach and small
intestine
That foods and fluids are withheld for 6 to 8 hours
before the procedure
That a sedative may be administered before the
procedure to promote relaxation
That full or partial dentures should be removed
before the procedure
That the test may be performed with the client in
a sitting or semireclining position
That a flexible, microscope-like instrument will
be inserted through the mouth and passed into
the stomach and small intestine
That the throat will be sprayed with a local anesthetic to make passage of the tube less uncomfortable
That this anesthetic will have a bitter taste, may
create a sensation of warmth, and may impair
swallowing
That a device may be inserted into the mouth to
protect the teeth and prevent biting the endoscope
That saliva will be removed by suctioning during
the procedure (similar to dental suctioning)
That after the tube is inserted, the client may be
assisted to a side-lying position
That air may be injected into the stomach during
the test to aid in visualization and that it may
cause a sensation of fullness or bloating
That the procedure may take from 45 minutes to
1 hour
That after the stomach and intestine have been
visualized and tissue samples obtained, the endoscope and mouth device will be removed
That vital signs will be monitored closely after the
procedure
That the client will not be permitted to eat or
drink until the local anesthetic has worn off
That activity may be restricted until the premedication has worn off
That the client should report immediately any
chest pain or upper abdominal pain, pain on
swallowing, difficulty in breathing, and expectoration of blood
Prepare for the procedure:
Remove full or partial dentures. If the client has
any permanent crowns on the teeth (i.e., “caps”),
the physician performing the test should be so
informed.

Provide a hospital gown.
Have the client void.
Take and record vital signs, and compare with
baseline values.
Administer premedication as ordered. (Premedication may consist of an analgesic or a tranquilizer to reduce discomfort and promote relaxation,
as well as atropine to reduce secretions.)
THE PROCEDURE

With the client seated in a semireclining position, a
local anesthetic is sprayed into the throat and may
also be swabbed in the mouth. A protective guard is
inserted to cover the teeth. A bite block may also be
inserted to maintain adequate opening of the mouth
without client effort.
The endoscope is passed through the mouth, and
the client is assisted to the left lateral position. The
dental suction device is inserted to drain saliva. The
esophagus may be examined and then the scope is
advanced into the stomach. Gastric lavage may be
performed to clear the stomach of residual. After the
stomach is examined, the scope is advanced into the
duodenum. Air may be injected through the endoscope to aid in visualizing structures. A cytology
brush or biopsy forceps is introduced through the
endoscope to obtain tissue samples. Specimens are
placed in appropriate containers and are sent to the
laboratory immediately. The dental suction device is
removed, the endoscope is withdrawn, and the tooth
guard and bite block are removed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to a position of comfort and
allowing the client to rest for a few minutes.
Maintain side-lying position for 1 to 2 hours to
prevent aspiration of secretions.
Remind the client not to eat or drink until the
local anesthetic has worn off and normal swallowing ability has returned.
Remind the client to report immediately any chest
or upper abdominal pain, pain on swallowing,
difficulty in breathing, and expectoration of
blood.
Take and record vital signs. Additional readings
may be required until vital signs are stable.
Assess and record breath sounds and characteristics of respirations.
Assess the client’s ability to swallow.
Assess the client’s recovery from the premedication.
Assess the client’s comfort level and report immediately any complaints of chest pain, epigastric
pain, periumbilical pain, and pain on swallowing.

CHAPTER 14—Analysis

Assess the client’s ability to resume usual food and
fluid intake.

LUNG BIOPSY
Lung biopsy is the removal of a sample of lung
tissue for cytologic and histological study. The
sample may be obtained through “closed” methods,
such as insertion of a needle through the chest
wall and fiber-optic bronchoscopy, or by “open”
biopsy, which entails a thoracotomy and general
anesthesia.
This test should be performed with caution and
only when necessary to obtain diagnostic information not otherwise available through less invasive
procedures.
Reference Values
No abnormal cells or tissue present
INDICATIONS FOR LUNG BIOPSY

Determination of the cause of diffuse pulmonary
disease of unknown etiology
Diagnosis of suspected malignancy, infection, or
parasitic infestation
Inconclusive results of less invasive tests such as
chest x-ray examinations, computed tomography
scans, and sputum analyses
CONTRAINDICATIONS

Bleeding disorders
Hyperinflation of the lung
Cor pulmonale
Inability of the client to cooperate for the procedure (contraindicates needle biopsies and bronchoscopies performed under local anesthesia)
Nursing Alert

Lung biopsies may result in bleeding into lung
tissue, pneumothorax, hemothorax, and infection.
Before the procedure, the client’s hematologic
status and blood clotting ability must be
assessed; therefore, a CBC, platelet level, PT,
PTT, clotting time, and bleeding time should
be performed.
After the procedure, the client’s vital signs,
lung sounds, and comfort level are monitored
closely for early detection of possible complications.

of Cells and Tissues

347

NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician
The method that will be used to obtain the sample
(needle biopsy, bronchoscopy, or thoracotomy)
The type of anesthesia to be administered (local
anesthesia for needle biopsies, topical or general
anesthesia for bronchoscopy, general anesthesia
for thoracotomy)
That foods and fluids are withheld for 6 to 8 hours
before the procedure, especially if bronchoscopy
is to be performed or general anesthesia is to be
used
That a sedative may be administered before the
procedure
That, if the specimen is to be obtained by bronchoscopy or thoracotomy, full or partial dentures
should be removed before the procedure
That, if a needle biopsy is to be performed, the
client should remain as still as possible and refrain
from coughing after the biopsy needle is inserted
That, if a bronchoscopy is to be performed, a
microscope-like instrument will be inserted
through the mouth and passed into the trachea
(“windpipe”)
That, if a thoracotomy is to be performed, a chest
incision will be made and a chest tube will be
inserted before the incision is closed
That, after the procedure, vital signs and respiratory status will be monitored closely
That, after the procedure, the client should report
immediately any difficulty in breathing or other
discomforts
That sputum samples may be collected after bronchoscopy
The type of activity restrictions that may be
necessary after the procedure
Prepare for the procedure:
For bronchoscopy or thoracotomy, remove full or
partial dentures. If the client has any permanent
crowns on the teeth (i.e., “caps”), the physician
performing the procedure should be so informed.
Provide a hospital gown.
Have the client void.
Take and record vital signs and compare with
baseline readings.
Administer premedication as ordered.
THE PROCEDURE

348

SECTION I—Laboratory

Tests

anesthetic, and draped with sterile drapes. The client
is reminded to remain as still as possible and to avoid
coughing during the procedure. The needle is
inserted through the posterior chest wall into the
selected intercostal space. A small incision may be
made before needle insertion. After insertion, the
needle is rotated to obtain the sample and is then
withdrawn. Pressure is applied to the biopsy site. If
there is no bleeding, a pressure dressing is applied.
The sample is placed in formalin solution and sent
to the laboratory immediately. If cultures are
desired, the sample can be divided into two portions,
with the portion for culture placed in a sterile
container.
For a bronchoscopy, the client is initially positioned in relation to the type of anesthesia to be
used. If general anesthesia is to be administered, the
client is placed in the supine position and anesthetized. The neck is hyperextended and the bronchoscope introduced through the mouth. If local
anesthesia is used, the client is seated and the tongue
and oropharynx are sprayed and swabbed with anesthetic. The client is then assisted to a supine or a
side-lying position and the bronchoscope is introduced through the mouth. Additional anesthetic is
applied through the scope as it approaches the vocal
cords and the carina, eliminating reflexes in these
sensitive areas. After inspection through the bronchoscope, the samples are collected by bronchial
brush or biopsy forceps. Specimens are placed in
appropriate containers and sent to the laboratory
immediately.
Open biopsies are performed in the operating
room under general anesthesia. A thoracotomy is
performed to obtain the sample, and a chest tube is
inserted after the procedure.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after a needle biopsy or bronchoscopy using local or topical anesthesia include
positioning the client in a semi-Fowler’s position to
permit maximum ventilation and allowing the client
to rest for a few minutes.
Monitor vital signs and compare with baseline
levels. Repeat at 15- to 30-minute intervals for 1 to
2 hours or until stable.
If a needle biopsy was performed, assess the
biopsy site for bleeding each time vital signs are
taken.
Assess breath sounds and observe for any signs of
respiratory distress. Evaluate the client’s comfort
level.
Resume foods and fluids withheld for the procedure if assessment data indicate that the client is
stable.

If a bronchoscopy was performed using local
anesthesia, monitor vital signs and observe for
signs of laryngospasm, bronchospasm, and laryngeal edema as indicated by wheezing, stridor,
absence of air movement at the mouth or nares,
anxiety, and cyanosis.
Provide gargles or lozenges for throat discomfort.
For an open biopsy, perform care and observation
in the same manner as for anyone who has had a
thoracotomy under general anesthesia.
Pneumothorax or hemothorax: Note and report
rapid and shallow respirations, dyspnea, air
hunger, chest pain, cough, hemoptysis, or absence
of breath sounds over the area. Prepare for needle
aspiration of air or fluid or for insertion of a chest
tube.
Infection: Note and report change in respiratory
status, chest pain, sputum that is yellow or other
color, or elevated temperature. Monitor vital
signs, administer ordered antibiotic therapy, and
obtain sputum cultures for laboratory analysis.

PLEURAL BIOPSY
Pleural biopsy is the removal of a sample of pleural
tissue for cytologic and histological study. It is
usually performed by needle biopsy and may be
undertaken as part of a thoracentesis (see Chapter
9). Open biopsy, requiring a thoracotomy using
general anesthesia, may also be performed.
This test should be performed with caution and
only when necessary to obtain diagnostic information not otherwise available through less invasive
procedures.
Reference Values
No abnormal cells or tissue present
INDICATIONS FOR PLEURAL BIOPSY

Evidence of pleural effusion of unknown etiology
Suspected tumor involving the pleura
Differentiation between benign and malignant
disorders involving the pleura
Determination of the cause of infection involving
the pleurae (i.e., viral, fungal, bacterial, and parasitic infections)
Diagnosis of fibrosis or collagen vascular disease
involving the pleurae
CONTRAINDICATIONS

Bleeding disorders
Inability of the client to cooperate in the procedure (contraindicates needle biopsies)

CHAPTER 14—Analysis

Nursing Alert

Pleural biopsies may result in bleeding into
lung tissue, pneumothorax, hemothorax, and
infection.
Before the procedure, the client’s hematologic
status and blood clotting ability must be
assessed. Therefore, a CBC, platelet level, PT,
PTT, clotting time, and bleeding time should
be performed.
After the procedure, the client’s vital signs,
lung sounds, and comfort level are monitored
closely for early detection of possible complications.
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician
The method that will be used to obtain the sample
(needle biopsy or open biopsy via thoracotomy)
The type of anesthesia to be administered (local
anesthesia for needle biopsy, general anesthesia
for open biopsy)
That foods and fluids are generally not withheld
before a needle biopsy but are restricted for 6 to 8
hours before an open biopsy
That a sedative may be administered before the
procedure
That, if a thoracotomy is to be performed, full or
partial dentures should be removed before the
procedure
That, if a needle biopsy is to be performed, the
client should remain as still as possible and refrain
from coughing after the biopsy needle is inserted
That, if a thoracotomy is performed, a chest incision will be made and a chest tube will be inserted
before the incision is closed
That, after the procedure, vital signs and respiratory status will be monitored closely
That, after the procedure, the client should immediately report any difficulty in breathing or other
discomfort
The type of activity restrictions that may be
necessary after the procedure
Prepare for the procedure:
For thoracotomy, remove full or partial dentures.
Assist the client to disrobe, and provide a hospital
gown.
Have the client void.
Take and record vital signs and compare with
baseline readings.
Administer premedication as ordered.

of Cells and Tissues

349

THE PROCEDURE

For a needle biopsy, the client is assisted to a sitting
position with arms supported on a pillow on an
overbed table. The needle insertion site is cleansed
with an antiseptic solution, infiltrated with a local
anesthetic, and draped with sterile drapes. The client
is reminded to remain as still as possible and to avoid
coughing during the procedure. The needle is
inserted through the posterior chest wall into the
selected intercostal space, rotated to obtain the
sample, and then withdrawn. Pressure is applied to
the biopsy site. If there is no bleeding, a pressure
dressing is applied. The sample is placed in formalin
solution and sent to the laboratory immediately.
Open biopsies are performed in the operating
room under general anesthesia. A thoracotomy is
performed to obtain the sample, and a chest tube is
inserted after the procedure.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after a needle biopsy include
positioning the client in a semi-Fowler’s position to
permit maximum ventilation.
Monitor vital signs and compare with baseline
levels. Repeat at 15- to 30-minute intervals for 1 to
2 hours or until stable.
Assess the biopsy site for bleeding each time vital
signs are taken.
Evaluate breath sounds and observe for any signs
of respiratory distress.
Evaluate the client’s comfort level.
Resume foods and fluids withheld before the
procedure if assessment data indicate that the
client is stable.
For an open biopsy, provide care and observation
as for anyone who has had a thoracotomy under
general anesthesia.

PROSTATE GLAND BIOPSY
Prostate gland biopsy involves the removal of a
sample of prostatic tissue for histological and cytologic examination. Several approaches to obtaining
the sample are possible: transurethral, transrectal,
and perineal. Possible complications include bleeding and infection at the biopsy site, although they are
not frequent problems.
Reference Values
No abnormal cells or tissue present
INDICATIONS FOR PROSTATE GLAND BIOPSY

Prostatic hypertrophy of unknown etiology

350

SECTION I—Laboratory

Tests

Suspected cancer of the prostate gland
CONTRAINDICATIONS

Bleeding disorders
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician
That foods and fluids are usually not restricted
before the test
That a sedative may be administered to promote
relaxation
The method that will be used to obtain the sample
The type of positioning that may be used for the
test (see “The Procedure”)
That a local anesthetic will be administered to
prevent pain but that the client may feel a “pinching” or “pulling” sensation during the procedure
The importance of remaining still during the
procedure
That an antibiotic may be administered to prevent
infection
That vital signs and urinary output will be monitored closely after the procedure
That, after the procedure, any rectal pain or bleeding, blood in the urine, or fever should be
reported immediately
Any special site care necessary (e.g., a dressing is
applied when the perineal approach is used)
Prepare for the procedure:
Administer enemas, if ordered—if the perineal or
transurethral approach is to be used, one enema is
usually ordered; if the transrectal approach is to
be used, saline enemas until clear may be ordered.
Provide a hospital gown.
Have the client void.
Take and record vital signs and compare with
baseline readings.
Administer premedication as ordered.
THE PROCEDURE

For the transurethral approach, the client is positioned on a urologic examination table as for a
cystoscopy (see Chapter 16). The external genitalia
are cleansed with antiseptic solution and a local
anesthetic is instilled into the urethra. The endoscope is then inserted. The prostate gland is visualized, and the tissue for biopsy is removed with a
cutting loop. The sample is placed in formalin solution and sent to the laboratory immediately. The
disadvantage of this approach is that malignant
nodules or tissue may not be included in the sample,
even though the endoscope is under direct visual
guidance.

For the transrectal approach, the client is assisted
to the Sims’ position, and a rectal examination is
performed to locate potentially malignant nodules.
A biopsy needle guide is then passed along the
examining finger and the stylet removed. The biopsy
needle is inserted through the needle guide and
rotated to obtain a core of tissue. The needle is then
withdrawn and the sample placed in formalin solution. The disadvantage of this approach is the perforation of the rectum and the creation of a tract
through which cells from the nodule may be seeded.
Possible complications include infection, hemorrhage, and perforation of the bladder.
For the perineal approach, the client is assisted to
the position desired by the physician, usually the
jack-knife or the lithotomy position, both achieved
by using a special examination or operative-type
table. The client is draped appropriately with the
perineum exposed. The perineum is cleansed with
an antiseptic solution and infiltrated with a local
anesthetic. A small incision is made and either a
biopsy needle or a biopsy punch inserted. Samples
are taken from several locations and placed in formalin solution. Digital pressure is applied to the site. If
there is no bleeding, a sterile dressing is applied.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to a comfortable position and
allowing the client to rest for a few minutes.
Monitor vital signs and compare with baseline
readings; repeat every 4 hours for 24 hours.
If the perineal approach was used, observe the
biopsy site for bleeding or other drainage.
If the transurethral approach was used, monitor
for resumption of usual voiding patterns.
Observe the appearance of the urine.
Remind the client to report immediately any rectal
pain or bleeding, blood in the urine, or fever.

THYROID GLAND BIOPSY
Thyroid gland biopsy involves the removal of a
sample of thyroid tissue for histological and cytologic examination. Thyroid tissue samples may be
obtained by needle aspiration (closed biopsy) or
surgical incision (open biopsy). Needle biopsies
require local anesthesia, whereas open biopsies are
performed in a manner similar to that used for a
thyroidectomy.
Reference Values
No abnormal cells or tissue present

CHAPTER 14—Analysis

INDICATIONS FOR THYROID GLAND BIOPSY

Abnormal thyroid scan
Thyroid gland enlargement of unknown etiology
Signs and symptoms of thyroiditis or hyperthyroidism
Presence of thyroid nodules of unknown etiology
to differentiate between benign and malignant
nodules
Differentiation between thyroid cysts and solid
tumors
Differentiation between inflammatory thyroid
diseases (Hashimoto’s thyroiditis versus granulomatous thyroiditis)
Confirmation of the diagnoses of hyperthyroidism and nontoxic nodular goiter
CONTRAINDICATIONS

Bleeding disorders

of Cells and Tissues

351

That the client may have a sore throat after the
procedure
Prepare for the procedure:
For a needle biopsy, the client is assisted to the
supine position and a small pillow, sandbag, or
folded blanket is placed under the shoulders; the
skin is cleansed with an antiseptic solution,
injected with a local anesthetic, and draped with
sterile drapes. The client is reminded not to swallow as the local anesthetic is injected. The biopsy
needle is inserted, the specimen obtained, and the
needle withdrawn. Pressure is applied to the
biopsy site. If there is no bleeding, a pressure
dressing is applied to the site. The sample is placed
in formalin solution and sent to the laboratory
immediately.
For an open biopsy, the sample is obtained
through surgical excision during the operative
procedure.

NURSING CARE BEFORE THE PROCEDURE

NURSING CARE AFTER THE PROCEDURE

Explain to the client:
That the procedure will be performed by a physician
The method that will be used to obtain the sample
(needle biopsy or open biopsy)
The type of anesthesia to be administered (local
anesthesia for needle biopsy, general anesthesia
for open biopsy)
That foods and fluids are generally not withheld
before a needle biopsy but are restricted for 6 to 8
hours before an open biopsy
That a sedative may be administered before the
procedure
That, if a needle biopsy is to be performed, the
client will be positioned on an examining table
with a pillow, sandbag, or folded blanket under
the shoulders to make the thyroid gland more
accessible
That, if a needle biopsy is to be performed, the
client should remain as still as possible and should
refrain from swallowing as the local anesthetic is
injected
That, if an open biopsy is to be performed, an
incision will be made at the front of the neck
That, after the procedure, vital signs and respiratory status will be monitored carefully

Care and assessment after a needle biopsy include
allowing the client to rest for a few minutes after the
procedure.
Monitor vital signs and compare with baseline
readings; repeat every 15 minutes for 1 hour,
every hour for 4 hours, and then every 4 hours for
24 hours.
Assess the biopsy site for bleeding each time the
vital signs are taken.
Evaluate the client for dyspnea, hoarseness, and
difficulty swallowing.
Monitor comfort level and administer analgesics
for throat discomfort.
For an open biopsy, provide care and observation
as for a client who has had a thyroidectomy.
REFERENCES
1. Porth, CM, Pathophysiology: Concepts of Altered States of Health,
ed 5, JB Lippincott, Philadelphia, 2000, p 80.
2. Ibid, p 85.
3. Ibid, p 98.
4. Ibid, p 98.
5. Ibid, p 86.
6. Ibid, p 98.
7. Ibid, p 98.
8. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 493.
9. Packer, B: Early prenatal testing—a chorionic villus update. Mothers
Today, May/June 1987, p 12.

CHAPTER

Culture and
Sensitivity Tests
TESTS COVERED
Blood Culture, 353
Eye and Ear Cultures, 354
Nose and Throat Cultures, 355

Wound Culture, 356
Skin Culture, 357
Genital and Anal Cultures, 358

INTRODUCTION

Cultures are the laboratory cultivation of substances collected from a
body site, using appropriate techniques and methods specific to the type of material to be
examined. For most infections, culture is considered the most effective method of laboratory
testing for obtaining a definitive diagnosis. Other methods used to detect and identify infectious microorganisms include microscopic examination (Gram, acid-fast, and other stains) and
immunologic techniques (microbial antigen detection).

CULTURES
A culture involves the introduction of material
to an artificial growth culture medium such as
liquid (broth), solid (agar), or cell culture lines,
which are classified as selective, nonselective, or
differential, depending on the growth support
needed by the suspected microorganisms. Liquid
and solid media are used to cultivate bacteria and
fungi, whereas cell lines are used to culture viruses
and chlamydiae.1 Material to be cultured can be
streaked along the culture medium or injected into
it. Culture media are contained in Petri dishes, test
tubes, and dilution containers. After the material is
introduced into the proper medium, the culture is
incubated for a specific length of time (usually 48 to
72 hours for agar and 3 to 7 days for broth media),
at a specific temperature (usually 95.0F [35C]),
and under other conditions suitable for the
suspected microorganism (e.g., CO2 for anaerobic
culture).2 Another 24 hours are needed to identify
352

the pathogen that is causing a particular infectious
disease.
Any excreted or secreted body fluid, drainage, or
tissue sample can be cultured for microorganism
identification. The types of materials collected and
the procedures followed for culture of sputum,
bronchial washings, feces, urine, tissue biopsy, cerebrospinal fluid, bone marrow, amniotic fluid,
semen, gastrointestinal materials, and body fluids
such as pleural, synovial, peritoneal, and pericardial
effusions are discussed in their respective chapters.
This chapter is confined to the materials collected
for culture tests of blood and from the following
sites: eye and ear; nose and throat; wounds; skin,
nails, and hair; and genital and anal areas.

ANTIMICROBIAL SUSCEPTIBILITY
In conjunction with the culture, microorganisms are
tested for sensitivity to specific antibiotics. This is
known as culture and sensitivity (C&S) testing.

CHAPTER 15—Culture

Bacteria are classified according to their reaction to
a number of antibiotics as (1) resistant (growth not
inhibited), (2) sensitive (growth inhibited), or (3)
intermediately sensitive (some inhibition).
The most common sensitivity test is the agar diffusion test. A special agar plate is inoculated with bacteria, filter disks prepared with antibiotics are applied
to the agar surface, and the plates are incubated. As
the numbers of bacteria increase and the antimicrobial agent concentration changes during incubation,
a zone of inhibition develops around each disk. The
diameters of the inhibition zones are measured and
compared to a sensitivity reference chart.3
Some sensitivity tests are made using a blood
sample containing the infectious agent cultured in a
liquid medium to determine the concentration of an
added antibiotic to inhibit bacterial growth (minimal inhibitory concentration). Penicillins and
cephalosporins are tested for effectiveness using the
-lactamase assay. Some bacteria produce an
enzyme (penicillinase) that renders these antimicrobials ineffective.4

SPECIMEN COLLECTION
REQUIREMENTS
In most instances, the nurse is responsible for
collecting specimens for C&S testing. To obtain the
most accurate diagnostic information, the nurse
should observe these requirements:
1. Use gloves and observe standard precaution
procedures (see Appendix III). Avoid contaminating the sample with the flora indigenous to
skin and mucosa.
2. Collect the specimen from the site with the
most viable and active microorganisms.
3. Collect the specimen at a time when the
microorganisms are present in large numbers,
preferably early in the disease, before antibiotic
therapy is begun.
4. Collect a sufficient quantity for a complete
analysis.
5. Collect the correct number of specimens at the
same time or at the correct time intervals.
6. Collect the specimen in sterile, disposable
containers or introduce into a container without contaminating either the specimen or the
outer surfaces of the container.
7. Take into consideration the microorganism’s
special needs for survival, such as an anaerobic
environment or particular media requirements. Use special kits for collection of such
specimens.
8. Label all specimens correctly with all pertinent
information regarding the client’s history and

and Sensitivity Tests

353

status, site, time, suspected infectious agent,
and tests ordered.
9. Transport the specimen to the laboratory
immediately to avoid overgrowth or death of
the microorganisms.

BLOOD CULTURE
Blood cultures are microbiologic tests undertaken to
assist in the diagnosis of bacteremia, septicemia, or
infectious diseases such as typhoid fever, plague, and
malaria. When bacteria or fungi enter the bloodstream, an infection of greater or lesser severity may
result. Pathogens entering the bloodstream from soft
tissue infection sites, contaminated intravenous (IV)
lines, or invasive procedures such as minor surgery,
tooth extraction, or cystoscopy usually do not result
in infections severe enough to cause sepsis. But if
the infection is persistent or recurrent, it can lead to
septicemia, a life-threatening condition that is
manifested by severe signs and symptoms of infection. In adults, the most common microorganisms
causing septicemia are Staphylococcus aureus, the
gram-negative rods such as Escherichia coli,
Aerobacter spp., and Klebsiella spp.; in infants, the
microorganisms are E. coli and -hemolytic streptococcus.5 In clients who have received antimicrobial
therapy before the test, an antimicrobial removal
device containing a resin is used to remove the
inhibitory effects of antibiotics from the blood
sample before culturing. This practice allows for
more rapid growth and identification of the organism. Test results are recorded as negative with no
growth or as positive if growth occurs.
Reference Values
Negative, no growth of pathogens in a specific
time span
INTERFERING FACTORS

Pretest antimicrobial therapy, which delays
growth of pathogens
Contamination of the specimen by the skin’s resident flora
Inadequate amount of blood or number of blood
specimens drawn for examination
Specimens that are tested more than 1 hour after
collection
INDICATIONS FOR BLOOD CULTURE

Determination of the cause of sudden change in
pulse and temperature with or without chills and
diaphoresis

354

SECTION I—Laboratory

Tests

History of persistent, intermittent fever associated
with a heart murmur
Intermittent or continuous temperature elevation
of unknown origin
Suspected bacteremia after invasive procedures
Identification of the cause of shock in the postoperative period
Immunosuppression, which predisposes to invasion by microorganisms that rarely invade a
healthy host
Fever and chills in debilitated or elderly persons
receiving hyperalimentation or antibiotic therapy
Determination of sepsis in the newborn as a result
of prolonged labor, early rupture of the
membranes, maternal infection, or neonatal aspiration6
Nursing Alert

Absolute sterile technique must be used when
performing the venipuncture and obtaining
the blood samples to prevent possible contamination. Measures must be taken during the
procedure to prevent transmission of infectious agents to the client or personnel.
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any study
involving the collection of a peripheral blood sample
(see Appendix I).
The client should be informed that a sample is
being obtained from the site and that the test
results can take 1 to 3 weeks, depending on the
suspected or underlying conditions.
A history should be obtained regarding the presence of fever of unknown origin, suspected bacterial or fungal infections, and antibiotic therapy.
THE PROCEDURE

The venipuncture site is cleansed with povidoneiodine and allowed to dry. The venipuncture is
performed using strict sterile technique and gloves.
Blood in the amount of 20 mL (30 mL if an infection
is suspected, or 1 to 3 mL in an infant or young
child) is withdrawn without allowing air to
be aspirated into the syringe. The needle is replaced
by a new sterile needle on the syringe. The caps of
the two culture bottles are removed and the tops
cleansed with povidone-iodine, allowed to dry, and
then cleansed with alcohol. Half of the blood is
injected into each bottle of aerobic media and
anaerobic media and gently mixed with the culture
media. The bottles should contain a 1:10 dilution of
blood and media. The bottles can also contain an

adsorbent resin to remove previously administered
antibiotics that can inhibit growth of the microorganisms. If the blood is not inoculated after withdrawal, it can be transported in a sterile tube
containing a preservative and placed in the bottles of
media in the laboratory. The procedure is repeated
at a different site immediately and in 3 hours or during a septic episode. Within 24 hours as many as four
cultures can be obtained to isolate the etiologic
agent.7 Cultures to isolate parasites in blood require
blood collected in a lavender-topped tube or blood
smears for microscopic examination.
Use standard precaution procedures for bloodborne pathogens when handling and disposing of all
articles used in blood culture collection (see
Appendix III).
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedures are the
same as for any study involving the collection of a
peripheral blood sample (see Appendix I).
Abnormal values: Note and report to the physician immediately any positive culture result and
microorganisms indicating bacteremia or
septicemia. Assess for fever, chills, hypotension,
and other signs and symptoms associated with
acute infection. Assess blood glucose and bilirubin in an infant with suspected sepsis. Administer
ordered antimicrobial and antipyretic therapy
orally or IV. Monitor vital signs and temperature,
and provide care and comfort measures for
elevated temperature, fatigue, and other
complaints.
Disease transmission: Note and report type of
infection, infectious agent, and client status (age,
immunosuppression). Observe preventive standards for blood-borne pathogens for hand protection, personal protection, and needles and sharps
(see Appendix III).

EYE AND EAR CULTURES
Eye cultures are performed on pus, corneal scrapings, or aspirate of intraocular fluid to establish the
bacterial or viral infectious agent involved in orbital
cellulitis, conjunctivitis, keratitis, and blepharitis.8
The specimen is obtained with a swab and Culturette. Among the pathogens causing infectious
diseases of the eye are Haemophilus aegyptius, Neisseria gonorrhoeae, Chlamydia, adenovirus, and herpesvirus.
Ear cultures are made on material from the outer,
middle, or inner ear to identify a microorganism
involved in a chronic infectious disease, local lesion
infections, and abscess formation. The specimen is

CHAPTER 15—Culture

obtained with a swab and Culturette. Outer ear and
external ear canal infections are usually associated
with skin conditions, whereas the middle and inner
ear are usually associated with either the spread of
infections from the nasopharynx or a systemic
infection.9 Among the pathogens causing ear infections are E. coli, Chlamydia spp., Proteus spp., hemolytic streptococci, S. aureus, Pseudomonas
aeruginosa, Candida albicans, and Aspergillus spp.
Test results for eye and ear cultures are recorded as
negative with no growth or as positive with the
infectious agent identified.
Reference Values
Negative, no growth of pathogens
INTERFERING FACTORS

Pretest antimicrobial therapy, which will delay
growth of pathogens
Contamination of the specimen by the surrounding skin or mucous membrane
Failure to collect an adequate amount of material
for culture
INDICATIONS FOR EYE AND EAR CULTURES

Ear pain, drainage, changes in hearing
Suspected infection in the outer, middle, or inner
ear
Eye redness, drainage, changes in vision
Determination of the causative agent of infection
of parts of the eye
Determination of effective local or systemic
antimicrobial therapy specific to identified
microorganism and sensitivity
NURSING CARE BEFORE THE PROCEDURE

Client preparation includes informing the client of
the reason for the procedure and the method of
obtaining the specimen (swab and Culturette).
A history should include information regarding
the presence of pain, redness, drainage from the
area, and antimicrobial therapy administered
before the test.

and Sensitivity Tests

355

into the external canal of the ear 1/4 inch and rotated
in the exudate. The swab is removed without touching the sides of the canal and is placed in the tube;
the end of the tube is squeezed to allow for dispersion of the medium.
To obtain an eye culture, the client is requested
to look upward, and a sterile swab is placed in the
inner canthus of the eye or on the affected surface of
the eye; the swab is then rotated to collect the
drainage material. The swab is placed in a Culturette
tube, and the end of the tube is squeezed to allow
for dispersion of the medium, or the swab is placed
in a special bottle of medium depending on the
suspected microorganism to be isolated.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
resuming eye or ear care and treatments.
Abnormal values: Note and immediately report
to the physician any positive culture results and
the microorganisms identified. Administer
ordered antimicrobial therapy. Provide eye or ear
care and treatments. Instruct client to wear dark
glasses, if needed. Instruct client in the procedure
for using eyedrops or eardrops and inform of the
need to avoid rubbing the eyes and the importance of hand washing to prevent transmission of
the microorganism to the other eye or other body
sites.

NOSE AND THROAT CULTURES
Culture sites of the upper respiratory tract include
the nares and the nasopharynx or throat. The
culture material is obtained by swab and Culturette.
The cultures are made to identify suspected infections or carrier states caused by S. aureus, group A
streptococci, N. gonorrhoeae, Corynebacterium diphtheriae, Bordetella pertussis, C. albicans, and
Haemophilus influenzae. The tests are commonly
performed on health personnel to screen for carriers.10 Test results are recorded as negative with
normal flora or as positive with the infectious agent
identified.

THE PROCEDURE

The client is placed in a sitting position with the
head tilted slightly backward for an eye culture or
turned to the side, exposing the ear to be cultured.
To obtain an ear culture, cleanse the area
surrounding the site with a swab containing a
cleansing solution to remove contaminating material or flora that has collected in the external ear.
Cerumen in the ear canal can be removed before
obtaining a specimen. A Culturette swab is inserted

Reference Values
Negative, no growth of pathogens
INTERFERING FACTORS

Pretest antimicrobial therapy, which delays the
growth of pathogens
Contamination of the specimen by the surrounding skin or mucosa

356

SECTION I—Laboratory

Tests

Improper technique or inadequate amount of
material to be tested
INDICATIONS FOR NOSE AND THROAT CULTURES

Screen for carriers of S. aureus or H. influenzae
and differentiate between these states and actual
infection.
Diagnose upper respiratory viral infections causing bronchitis, pharyngitis, croup, and influenza.
Diagnose bacterial infections such as tonsillitis,
diphtheria, thrush, gonorrhea, pertussis, or streptococcal throat infection.
Determine the cause of scarlet fever, rheumatic
fever, and acute glomerulonephritis.
Obtain sputum specimens from children, as
necessary.
Determine effective antimicrobial therapy specific
to identified microorganism and sensitivity.
NURSING CARE BEFORE THE PROCEDURE

Client preparation includes informing the client or
caregiver, or both, of the reason for the procedure
and the method of obtaining the specimen (swab
and Culturette).
A history should include information regarding
the presenting signs and symptoms, past immunizations, and antimicrobial therapy administered
before the test.
THE PROCEDURE

The client is placed in a sitting position or, if a child,
on the caregiver’s lap with the head and body held to
immobilize while the procedure takes place.
To obtain a nasal culture, gently raise the tip of
the nose, insert a flexible swab into the nares and
rotate it in place against the sides. Then remove the
swab and place it in the appropriate medium to be
transported to the laboratory for immediate examination.
To obtain a nasopharyngeal culture, gently raise
the tip of the nose, insert a flexible swab along
the bottom of the nares, and guide it along until
it reaches the posterior pharynx. Rotate the swab
in place to obtain the secretions and then remove.
Then place the swab in the culture tube with
the appropriate medium and transport it to the
laboratory.
To obtain a throat culture, tilt the head slightly
backward, depress the tongue with a tongue blade,
and insert the swab through the mouth to the
pharyngeal and tonsillar area without touching any
part of the oral cavity. Rub the areas, including any
lesions, inflammation, or exudate, with the swab.
Remove the swab and squeeze the Culturette tube
before the swab is introduced into the medium.

Transport the specimen to the laboratory for immediate testing.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
resumption of the treatment regimen for signs and
symptoms of upper respiratory infections.
Abnormal values: Note and report positive
culture results to the physician. Administer
ordered antimicrobial therapy. Provide comfort
measures and treatment such as antiseptic gargles;
warm, moist applications; and inhalants.
Disease transmission: Practice standard precaution procedures in collection and transportation
of specimens and disposal of used articles (see
Appendix III). Instruct client to cover mouth and
nose when coughing or sneezing; advise regarding
tissue disposal and frequent hand washing.
Manage identified carriers among personnel
according to agency policy to prevent transmission to ill clients.

WOUND CULTURE
Wound culture is used to isolate and identify
pathogens that cause infection so that the physician
can prescribe the appropriate therapy. Wound
exudates and drainage as well as tissue samples can
be obtained from the actual site of infection.
Specimens are collected from a superficial wound
with a cotton-tipped sterile swab and Culturette
tube containing the medium. From a deep wound,
specimens are obtained by aspirating drainage with
a syringe and needle and injecting the material into
a tube of culture medium. Wound debridement or
excised tissue specimens can also be collected and
cultured.
Wound infections are most likely to occur after
trauma, surgical incision, or any other condition
that results in abscess or skin breaks, for example,
decubitus ulcer. Both aerobic and anaerobic
microorganisms can be identified in wound culture
specimens. Some bacterial infectious agents found
in wounds are S. aureus, group A streptococci;
Clostridium perfringens, Klebsiella spp., Proteus
spp., Pseudomonas spp., Mycobacterium spp., and the
fungal infectious agents C. albicans and Aspergillus
spp.11 Test results are recorded as either normal flora
and negative for growth or positive with the infectious agent identified.
Reference Values
Negative, no growth of pathogens

CHAPTER 15—Culture

INTERFERING FACTORS

Pretest antimicrobial therapy, which will delay
growth of pathogens
Specimens that are tested more than 1 hour after
collection
A dried specimen, which cannot be effectively
cultured for microorganism isolation
INDICATIONS FOR WOUND CULTURE

Determination of an infectious agent as the cause
of redness, warmth, or edema with drainage at a
site
Presence of pus or other exudate in an open
wound
Suspected abscess or deep wound infectious
process
Suspected wound infection after trauma
that causes break in the first line of defense
(skin)
Stage III and IV decubitus ulcers to determine
presence of infectious agents
Determination of effective antimicrobial therapy
specific to identified microorganism and sensitivity
NURSING CARE BEFORE THE PROCEDURE

Client preparation includes informing the client
of the reason for the procedure and the method
of obtaining the culture specimen (swab or aspiration).
A history should include the presence of pain,
edema, redness, warmth, and drainage of an
area; trauma or invasive procedures; and antimicrobial therapy administered before the suspected
infection.
THE PROCEDURE

The client is placed in a comfortable position
and draped; the site to be cultured should be
exposed. The area around the wound is cleansed to
remove flora indigenous to the skin. A Culturette
swab is placed in the most excessive exudate in a
superficial wound without touching the wound
edges. The swab soaked with the exudate is placed in
the tube, and the tube is squeezed to allow for
dispersion of the medium. More than one swab and
Culturette tube can be used to obtain specimens
from other areas in the wound. A deep wound
specimen is obtained by aspiration with a sterile
syringe and needle inserted directly into the wound.
After the aspiration, the air is expelled from the
syringe and the needle covered with a rubber stopper or the material injected into a tube containing
an anaerobic culture medium.

and Sensitivity Tests

357

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
dressing the wound as appropriate and leaving the
client in a comfortable position.
Abnormal values: Note and immediately report
to the physician any positive culture results and
the microorganisms identified. Assess for signs
and symptoms associated with an infectious
process. Administer ordered antimicrobial therapy. Provide wound care and treatments and
nutritional requirements to promote wound healing.
Disease transmission: Note and report type of
infection, infectious agent, and need for wound
precaution measures. Observe standard precaution procedures in the care of the wound and articles used to collect and test specimens (see
Appendix III).

SKIN CULTURE
Skin culture is performed on skin scrapings or
exudate, nail scrapings, or hair stubs. Skin culture is
used to identify bacterial and fungal infections and
to perform antimicrobial sensitivity testing. Cultural
identification is made from the growth of a microorganism on a specialized agar or broth medium incubated at a specific temperature. Direct slide
preparations are made from scrapings spread on a
slide and stained or unstained for microscopic
viewing. Normally, the hair, skin, and nails contain
nonpathogenic surface contaminants in low
numbers. The same resident microorganisms can
be pathogenic when present in large numbers.
Positive culture results are reported with the name of
the pathogen and the number of colonies. Stains
are reported for the presence and type of inflammatory cells and their staining characteristics.
Pathogens found on the hair include Blastomyces,
Coccidioides, Candida, Trichophyton, and Microsporum. Pathogens found on the nails include
Candida, Cephalosporium, Epidermophyton, and
Trichophyton. Pathogens found on the skin include
Bacteroides, Clostridium, Corynebacterium, Candida,
Epidermophyton, Trichophyton, Aspergillus, Pseudomonas, the common Staphylococcus, and group A
streptococcal organisms.
Reference Values
Normally low numbers of microorganisms on
the skin, hair, and nails
No evidence of large quantities of pathogens
identified

358

SECTION I—Laboratory

Tests

INTERFERING FACTORS

Failure to obtain a specimen from the proper
location or a sufficient quantity of scrapings,
fluid, or other material to be cultured
Failure to transport the specimen as soon as it is
collected
Drying of specimens or use of an improper
container for the specimen
INDICATIONS FOR SKIN CULTURE

Diagnosis of superficial or cutaneous infections of
the integument
Skin eruptions such as pustules, vesicles, or
lesions; scalp or nail abnormality
Determination of sensitivity to specific antimicrobials for use in treatment of the infection
NURSING CARE BEFORE THE PROCEDURE

Inform the client of the reason for the procedure
and the method of obtaining the culture specimen.
Advise the client that the culture is collected
by the physician or nurse in 5 to 10 minutes
and that results should be available in 48 to 72
hours.
Inform the client that little or no pain is associated with the procedure.
The history should include information about
acute and chronic skin conditions, signs and
symptoms indicating a need for a culture, other
skin tests, and the results.
THE PROCEDURE

The client is placed in a comfortable position with
the culture site exposed. The area is gently cleansed
with sterile saline and alcohol and allowed to air-dry.
Hair stubs, including the shaft and root, or scrapings
from the area affected are clipped or plucked with a
sterile forceps and sent to the laboratory in a Petri
dish for incubation and identification of the organism. Nail scrapings are obtained with a sterile scalpel
or clippings with a sterile scissors and placed in a
Petri dish or clean envelope. The specimen is transported to the laboratory for incubation and examination. Skin scrapings from several lesion edges are
obtained with a sterile scalpel and placed in a Petri
dish or spread on a slide for smear examination.
Fluid from a vesicle or pus from a pustule is
obtained by aspiration with a sterile needle and
tuberculin syringe, and the exudate is flushed on the
culture medium in a Petri dish. If fluid is not present, the lesion is opened with a sterile applicator and
swabbed for collection of the material; then the
applicator is placed in a sterile culture tube to be
transported to the laboratory for examination. Dark,

warm, and moist areas in the folds of the skin (axillary, groin, submammary) or nares can also be
cultured to identify causes of rashes with welldefined borders (usually fungal). The result of skin
cultures reveals the specific bacterial, fungal, or viral
infectious agent in sufficient quantities to indicate
pathology.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
telling the client that test results can be expected in
48 to 72 hours and that treatment (topical or
systemic medications) can be prescribed by the
physician at that time.

GENITAL AND ANAL CULTURES
Most genital and anal specimens are cultured to
identify possible sexually transmitted diseases
(STDs). The specimen is obtained with a swab
and Culturette or cultured on various media,
depending on the suspected organism. Immunoassay methods are also used to detect and identify
specific infectious agents. Specimens can be obtained from the mouth-throat, anal-rectal, urethral,
cervical, and vaginal sites. Tests help to identify
infectious processes associated with herpes simplex
virus, Chlamydia, Candida, Mycoplasma, and
Gardnerella vaginalis, as well as other infections
caused by N. gonorrhoeae, Treponema pallidum, and
Trichomonas vaginalis. Tests are also performed
to detect toxin-producing strains of S. aureus in
vaginal infections associated with toxic shock
syndrome.12 Test results are recorded as negative
with normal flora or as positive with the infectious
agent identified.
Reference Values
Negative or no growth of pathogens
INTERFERING FACTORS

Pretest antimicrobial therapy, which delays
growth of pathogens
Contamination of the specimen by the surrounding skin, mucosa, or feces
Improper collection technique or inadequate
amount of material to be tested
INDICATIONS FOR GENITAL AND ANAL CULTURES

Genital itching and purulent drainage
Diagnosis of STDs in those with the signs and
symptoms associated with the mouth and throat
(caused by oral sexual practices), anus (caused by

CHAPTER 15—Culture

anal sexual practices), and vagina or penis (caused
by traditional sexual practices)

and Sensitivity Tests

359

it in a tube of saline medium and transporting it to
the laboratory for immediate testing.

NURSING CARE BEFORE THE PROCEDURE

NURSING CARE AFTER THE PROCEDURE

Client preparation includes informing the client of
the reason for the procedure and the method of
obtaining the specimen (swab).
A history should include information regarding
sexual practices, itching and drainage of the
affected site, and antimicrobial therapy administered before the test.

Care and assessment after the procedure include
resumption of treatment regimen for STDs or other
inflammatory or infectious states of the genitoreproductive tract.
Abnormal values: Note and report positive
culture results to the physician and to the health
department, if appropriate. Administer ordered
antimicrobial therapy. Provide a comfortable,
sensitive, nonjudgmental environment for the
client, who may experience embarrassment with
the diagnosis.
Disease transmission: Practice standard precaution procedures in collection and transportation
of specimens (see Appendix III). Inform client of
safe sex practices for client and partner. Instruct
in vaginal suppository and douche procedures
and topical medication administration to treat
specific conditions.

THE PROCEDURE

Place the client in a lithotomy position and drape for
privacy. Observe standard precautions and procedures including the use of gloves in specimen collection, handling, transporting, and testing of body
drainage materials.
To obtain an anal culture, insert the swab 1 inch
into the anal canal; rotate and move the swab from
side to side to allow it to come in contact with the
microorganisms. Then remove the swab, place it in
the appropriate transport medium, and send it to
the laboratory for immediate testing.
To obtain a urethral culture in men, insert the
loop swab into the penile meatus to obtain a sample
of the discharge by gently scraping the anterior
mucosa. Then place the swab in the appropriate
transport medium and send it to the laboratory for
immediate testing.
To obtain a vaginal and endocervical culture in
women, insert a vaginal speculum and gently cleanse
mucus from the cervix with cotton. Then insert the
swab into the endocervical canal. Rotate the swab to
collect the secretions containing the microorganisms, remove, and place in the appropriate culture
medium, depending on the suspected pathogen.
Vaginal material can also be collected by moving the
swab along the sides of the mucosa and then placing

REFERENCES
1. Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, p 467.
2. Ibid, pp 471–472.
3. Ibid, pp 479-480.
4. Corbett, JV: Laboratory Tests and Diagnostic Procedures with
Nursing Diagnoses, ed 3. Appleton & Lange, Norwalk, Conn, 1992,
p 415.
5. Ibid, p 423.
6. Ibid, p 423.
7. Washington, JA: Medical bacteriology. In Henry, JB: Clinical
Diagnosis and Management by Laboratory Methods, ed 18. WB
Saunders, Philadelphia, 1991, pp 1027–1028.
8. Sacher and McPherson, op cit, p 515.
9. Ibid, p 515.
10. Ibid, p 429.
11. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed 4.
JB Lippincott, Philadelphia, 1992, p 434.
12. Corbett, op cit, p 434.

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SECTION

Diagnostic
Tests and
Procedures

361

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CHAPTER

Endoscopic Studies
PROCEDURES COVERED
Laryngoscopy, 364
Bronchoscopy, 367
Mediastinoscopy, 371
Thoracoscopy, 372
Esophagogastroduodenoscopy, 374
Endoscopic Retrograde
Cholangiopancreatography, 376
Proctosigmoidoscopy, 379

Colonoscopy, 381
Cystoscopy, 383
Colposcopy, 385
Culdoscopy, 387
Amnioscopy, 388
Laparoscopy, 389
Arthroscopy, 394

INTRODUCTION

Internal body structures can be visualized directly using an endoscope,
a tubular instrument with a light source and a system of lenses through which body organs and
hollow cavities can be observed. The endoscope can be inserted through a natural body orifice
or through a small incision.1
Endoscopes are of two basic types: rigid metal tubes (Fig. 16–1) and flexible fiber-optic
scopes (Fig. 16–2). Rigid metal tubes are the earliest type of endoscope available and are still
used in certain situations, usually when a larger tube diameter is needed, depending on the
body structures to be visualized and the purpose of the procedure. Flexible fiber-optic scopes
involve the transmission of images over flexible, light-carrying bundles of glass fibers. Because
flexible fiber-optic scopes are capable of transmitting light around curves, they can provide
views of body areas that are inaccessible with rigid scopes. The scopes contain a part for the
insertion of medications, instruments for suctioning, and other instruments that can be used
in the procedure. Specialized instrument accessories give these scopes additional capabilities,
such as obtaining biopsy specimens, coagulating bleeding vessels, removing foreign objects, and
obtaining photographs for future reference and comparisons. A cross-section of the bending
portion of a fiber-optic scope is shown in Figure 16–3. Because they cause less discomfort, the
fiber-optic scopes have better client acceptance and can be used with local rather than general
anesthesia in adults.
Specialized endoscopes of varying diameters and lengths are available, depending on the
type of procedure to be performed and whether the client is an adult or child. Emerging technical applications include the use of lasers, video systems, and computers with endoscopic
devices.
Endoscopic procedures are generally considered invasive, and a signed informed consent is
required unless specified otherwise in some of the procedures. Client preparation for an adult
is similar to that of a minor surgical procedure with local anesthesia and for a child it is the same
as a surgical procedure requiring general anesthesia. Endoscopic examinations or surgical
procedures are performed in specially equipped endoscopy rooms, in operating rooms, in the
363

364

SECTION II—Diagnostic

Tests and Procedures

Figure 16–1. Standard rigid endoscope.

Figure 16–2. Fiber-optic endoscope.

Figure 16–3. Cross-section view of the fiber-optic
endoscope.

outpatient department, or at the bedside, depending on the study. Physicians with special training and expertise in procedures related to their specialties perform the procedures; that is, a
bronchoscopy is performed by a pulmonologist, and a colonoscopy by a gastroenterologist.
Procedures and treatments by endoscopy are performed using sterile technique and standard
precaution procedures.

ENDOSCOPIC PROCEDURES
Endoscopic procedures are named for the organ or
body area to be examined or treated, including the
larynx, trachea, bronchi, pleurae, mediastinum,
pericardium, esophagus, stomach, duodenum,
pancreas, bile ducts, liver, colon, rectum/sigmoid
colon, bladder, urethra, ureters, prostate, vagina,
cervix, uterus, fetus, fallopian tubes, ovaries, and
joints.

LARYNGOSCOPY
Laryngoscopy is the visualization of the larynx. It
can be performed by indirect or direct technique.
The larynx is an organ that connects the pharynx
with the trachea. It is associated with speech and

protects the lungs as the epiglottis covers the larynx
during swallowing, preventing foods and fluids from
entering the trachea and lungs.
INDIRECT LARYNGOSCOPY

Indirect laryngoscopy is the visualization of the
reflected image of the larynx using a laryngeal
mirror, a head mirror, and a light source2 (Fig.
16–4). This procedure can be performed by a nurse,
physician, or other health-care professional in
almost any setting. A signed informed consent is
required only if tissue is to be removed.
DIRECT LARYNGOSCOPY

Direct laryngoscopy is performed with a rigid laryngoscope or a flexible fiber-optic endoscope and

CHAPTER 16—Endoscopic

Studies

365

Figure 16–4. Indirect laryngoscopy.

permits a more prolonged and thorough visualization of the larynx than does an indirect laryngoscopy. It is usually performed by a physician, but it
can be carried out by a nurse anesthetist in an emergency if a laryngoscope is used. In an emergency, the
procedure can be performed in almost any setting
provided that the necessary equipment is available.
Reference Values
Normal larynx with no inflammation, abnormal
growths, or foreign objects
INTERFERING FACTORS

Indirect Laryngoscopy
Inability to cooperate with the procedure
Excessive gagging
Large oropharyngeal mass or severe hypertrophy
of tonsillar tissue
INDICATIONS FOR LARYNGOSCOPY

Indirect Laryngoscopy
History of ingestion or inhalation of a foreign
body, with removal if visualized and accessible
Determination of the source of laryngeal stridor
of unknown etiology in the presence of actual or
risk for airway obstruction
Persistent cough, hemoptysis, throat pain, hoarseness or irritation, to identify possible cause such
as lesions or inflammation of the larynx
Simple excision of laryngeal polyps
Direct Laryngoscopy
History or symptoms, or both, of laryngeal
obstruction or disease (see previous section)
Determination of the presence of strictures,
edema, or other abnormalities
Suspected tumor to aid in the diagnosis of a
malignancy

Removal of a benign lesion or foreign body in the
larynx3
Removal of tissues or secretions, or both, for laboratory examination
Examination of areas that cannot be visualized as
clearly by the indirect laryngoscopy method
Examination of the larynx in children and adults
who require general anesthesia or who are otherwise unable to cooperate in an indirect laryngoscopy
Examination of the larynx in clients who have a
strong gag reflex
Suspected congenital laryngeal stridor, subglottic
stenosis, laryngeal webs, or Pierre Robin
syndrome in infants4
CONTRAINDICATIONS

Indirect Laryngoscopy
Presence of epiglottitis in children with its potential for edema and airway obstruction after the
procedure (Note: If absolutely necessary, this
examination can be performed by a physician if
supplies and equipment for intubation or
tracheostomy are available.)
Nursing Alert

Attempts to visualize the larynx or epiglottis
using a tongue depressor or any other article
in children with epiglottitis can precipitate
laryngospasm, complete obstruction, and
death.

NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The location for the procedure and the person
performing it
The method by which the examination will be
performed (direct or indirect)

366

SECTION II—Diagnostic

Tests and Procedures

That, after the procedure, the client should immediately report any difficulty in breathing
That discomfort will be minimized by local or
general anesthesia (age and mentation dependent)
If indirect laryngoscopy is to be performed, explain
to the client:
That there are no fluid and food restrictions
before the procedure
That the procedure requires 5 minutes or less
That the client will be requested to maintain a
sitting position and protrude the tongue as far as
possible
That the tongue can be held in the protruded
position by the client or an assistant to maintain
the tongue’s position throughout the procedure
That the client will be observed after the procedure and offered comfort measures, if needed
If direct laryngoscopy is to be performed, explain to
the client:
That the procedure requires about 15 to 30
minutes
That food and fluids are restricted for 6 to 8 hours
before the procedure
That anesthesia can be achieved by spraying or
swabbing the throat while in a sitting position or
that a general anesthetic can be administered, if
warranted, depending on the client’s age and
condition
That the local anesthetic has a bitter taste and can
cause sensations such as a thickened tongue and
difficulty in swallowing
That a sedative or antianxiety agent can be
administered before the procedure to promote
relaxation and that, possibly, a medication can be
administered to reduce secretions
That the client will be observed and activities
restricted after the procedure until the medication
or anesthesia has worn off
That foods and fluids will be withheld until the
ability to swallow has returned (usually about 2
hours after the procedure)
That comfort measures and medications will be
administered to alleviate throat discomfort after
the procedure
Prepare for the procedure:
Obtain a history of allergies to medications or
anesthetics and known or suspected upper respiratory disorders.
Ensure that dietary and fluid restrictions have
been followed before the procedure.
Remove full or partial dentures and inform the
person performing the test whether the client has
any permanent crowns on the teeth (caps).
If direct laryngoscopy is performed:

Have the client disrobe from the waist up and
provide a hospital gown.
Have the client void.
Obtain and record baseline vitals signs for later
comparison readings.
Administer premedications, if ordered, subcutaneously (SC) or orally with a small amount of
water 30 to 60 minutes before the procedure.
(Premedications can include an analgesic such as
meperidine [Demerol] to reduce discomfort, a
sedative or an antianxiety agent such as diazepam
[Valium] to promote relaxation, or an anticholinergic such as atropine sulfate to reduce secretions.)
THE PROCEDURE

The procedure varies with the type of endoscopic
study to be performed and the type of anesthesia
used.
Indirect Laryngoscopy. The client is seated in a
chair and the light source is positioned to reflect the
light from the operator’s head mirror into the
mouth (see Fig. 16–4). The throat is sprayed or
swabbed with a local anesthetic. The client is
instructed to concentrate on controlled breathing to
prevent gagging. A laryngeal mirror is placed in the
mouth as far posteriorly as possible and rotated to
reflect light into the larynx. If the examination
requires more than 2 to 3 minutes, the client is
permitted to swallow, and the examination is
resumed. Tissue can be excised for examination and
foreign bodies can be removed during the procedure. Specimens that are collected are placed in
appropriate containers, properly labeled, and
promptly sent to the laboratory.
Direct Laryngoscopy. The initial portion of the
procedure can vary, depending on the type of anesthesia used. If general anesthesia is used, the client is
placed in the supine position and the anesthesia
administered. If local anesthesia is used, the client is
placed in a sitting position and the mouth and
throat swabbed or sprayed, or both, with the anesthetic. When loss of sensation is adequate after the
local administration, the client is placed in the
supine position with the neck extended and
supported by an assistant. A laryngoscope or flexible
endoscope is introduced into the mouth and
advanced through the pharynx into the larynx for
visualization. Tissue can be excised and foreign
objects removed. Specimens are placed in appropriate containers, properly labeled, and promptly sent
to the laboratory. The scope is removed and the
client, if conscious, is placed in a semi-Fowler’s position. The client who has received a general anesthetic

CHAPTER 16—Endoscopic

Studies

367

is placed in a side-lying position with the head
slightly elevated.
NURSING CARE AFTER THE PROCEDURE

Indirect Laryngoscopy. Provide the client with a
cool drink or mouthwash to alleviate dryness of the
tongue and lozenges for any postprocedure discomfort when the gag reflex returns.
If a local anesthetic is used, monitor the ability to
swallow until sensation returns.
Direct Laryngoscopy. Maintain the client for about
2 hours in the position appropriate to the type of
anesthesia used. Monitor vital signs, compare with
baselines, and assess swallowing ability continuously.
Advise the client to refrain from smoking for
several hours after the procedure and to withhold
food and fluids until swallowing ability returns.
Apply cool compresses to the throat to reduce any
laryngeal edema resulting from trauma of the
scope or removal of tissue.
Provide warm saline gargles, lozenges, or viscous
lidocaine (Xylocaine) to alleviate throat discomfort.
Remind the client to report any excessive bleeding
or breathing difficulty immediately.
Assist with client’s transportation home if the test
is performed in an ambulatory care setting.
Reaction to anesthetic agent: Note and report
tachycardia, palpitations, hyperpnea, or hypertension. Administer ordered antihistamine. Initiate
intravenous (IV) line and resuscitation procedure
if needed.
Persistent bleeding: Note and report amount of
excessive hemoptysis or changes in vital signs for
potential hypovolemia. Provide tissues and an
emesis basin, and caution client against coughing
and throat clearing, which can dislodge a clot at
the tissue excision site and precipitate bleeding.
Initiate IV line and prepare to replace fluid loss.
Prepare client for laryngeal examination to
control bleeding at the site.
Tracheal perforation during the procedure: Note
and report difficulty in breathing or subcutaneous
crepitus on the face or neck indicating subcutaneous emphysema. Assist to initiate resuscitation
or tracheostomy procedures to maintain ventilation.

BRONCHOSCOPY
Bronchoscopy is the direct visualization of the
larynx, trachea, and bronchial tree by means of
either a rigid or a flexible bronchoscope. Its purposes

Figure 16–5. Bronchoscopy with fiber-optic endoscope.

are both diagnostic and therapeutic (Fig. 16–5). The
trachea divides into the left and right primary
bronchi, with the right shorter and wider and the left
longer and narrower. The primary bronchi divide
into the secondary bronchi, which divide to form the
segmental bronchi. Branching continues until the
terminal bronchioles are formed.5 Bronchial smooth
muscle tone is controlled by the autonomic nervous
system. The narrowing of bronchioles caused by
bronchospasm of these muscles results in impaired
airflow and ineffective breathing pattern and airway
clearance.
The rigid bronchoscope is designed to allow visualization of the larger airways, including the lobar,
segment, and subsegmental bronchi, while maintaining effective gas exchange. The lumen of the
bronchoscope is large enough to allow for the insertion of instruments such as biopsy forceps and electrocautery devices. A rigid bronchoscope is used
with laser therapy to remove lesions. A specialized
attachment allows for mechanical ventilation during
the procedure. Although it can require general anesthesia, rigid bronchoscopy is preferred to flexible
bronch for aspirating large volumes of blood or
secretions, or both; for removing foreign bodies; for
obtaining larger sized biopsy specimens than is
possible with a fiber-optic bronchoscope; and for
performing most bronchoscopies in children.6
The flexible fiber-optic bronchoscope has a
smaller lumen than that of the rigid bronchoscope
and is designed to allow for visualization of all

368

SECTION II—Diagnostic

Tests and Procedures

segments of the bronchial tree, entry into all thirdorder bronchi and half of the sixth-order bronchi,
and visualization of the openings of most sixthorder bronchi. Some now allow for visualization of
tenth-order bronchi. It is in the smaller airways that
bronchogenic carcinomas arise; therefore, this type
of bronchoscope allows for the detection and biopsy
of tissues that cannot be visualized with a rigid
bronchoscope via an accessory lumen. In general,
they are less traumatic to the surrounding tissues
than are the larger rigid scopes. Most fiber-optic
bronchoscopies are performed under local anesthesia, and client tolerance is better than for rigid bronchoscopy.7
Bronchoscopies can be performed in almost any
setting. In an emergency, a bedside bronchoscopy
can be performed, provided that equipment is available for oxygen delivery, cardiac monitoring, and
cardiopulmonary resuscitation.8
Reference Values
Normal larynx, trachea, bronchi, bronchioles,
and alveoli; absence of tracheoesophageal fistula
in infant if contrast studies are performed with
the bronchoscopy
INTERFERING FACTORS

Inability to cooperate during the procedure if it is
performed under local anesthesia
Failure to follow dietary and fluid restrictions
Improper handling and care of a specimen
removed for examination
INDICATIONS FOR BRONCHOSCOPY

Determination of the cause of persistent cough,
hemoptysis, or hoarseness of unknown etiology
Determination of the cause of unexplained chest
x-ray abnormalities such as pulmonary infiltrates
or tumor
Coughing, choking, or cyanosis of an infant
during feeding
Respiratory distress and tachypnea if secretions
are aspirated in an infant to rule out tracheoesophageal fistula or other congenital anomaly
Determination of the cause of unexplained
abnormal cytologic findings in sputum
Suspected bronchogenic carcinoma to obtain
samples by bronchial washings or brushings or by
biopsy for cytologic analysis
Determination of the stage of known bronchogenic carcinoma to assist in determining the
approach to treatment protocols
Local treatment of known lung cancer through

instillation of chemotherapeutic agents, implantation of radioisotopes, or laser palliative therapy
Abnormal exudate secured by thoracentesis to
determine the cause (cancer, infection, tuberculosis) by performing a pleuroscopy via bronchoscopy into the pleural space9
Identification of hemorrhagic and inflammatory
changes seen in endobronchial Kaposi’s sarcoma
associated with acquired immunodeficiency
syndrome
Diagnosis of opportunistic lung infections caused
by Pneumocystis, Nocardia, cytomegalovirus, invasive fungi, and parasites, especially in immunosuppressed clients
Diagnosis of tuberculosis, abscesses, pulmonary
infections (coccidioidomycosis, histoplasmosis,
blastomycosis, phycomycosis)
Inhalation of a foreign body, with removal if visualized and accessible
Smoke inhalation injury or other traumatic injury
to the tracheobronchial tree to determine the
nature and extent of tissue damage
Evaluation of airway patency in clients suspected
of having stenosis, strictures, tumors, or abnormal
bifurcation of the bronchi
Identification of bleeding sites within the tracheobronchial tree, with removal of blood and clots,
and the tamponade or coagulation of bleeding
sites
Aspiration of deep or retained secretions or
mucous plugs to improve airway patency, especially in clients with atelectasis
Evaluation of possible airway obstruction in
clients with a known or suspected sleep apnea
condition
Intubation of clients in situations using the fiberoptic bronchoscope as a guide for the endotracheal tube when technical difficulties can be
encountered, as in cervical spine injuries or
massive upper airway edema
Evaluation of endotracheal tube placement
Evaluation of possible adverse sequelae of intubation or tracheostomy
CONTRAINDICATIONS

Bleeding disorders, especially those associated
with uremia and cytotoxic chemotherapy
Hypoxemic or hypercapnic states that require
continuous oxygen administration
Pulmonary hypertension that can be associated
with an increased risk of hemorrhage from the
procedure
Cardiac conditions or dysrhythmias that can be
exacerbated as a result of the procedure
Disorders that limit extension of the neck that can

CHAPTER 16—Endoscopic

be contraindicated if the procedure is to be
performed with the rigid bronchoscope
Severe obstructive tracheal conditions such as
stenosis that prevent passage of the scope or
prevent air passage around the scope for ventilation during the procedure
Presence of or potential for respiratory failure,
because introduction of the bronchoscope alone
can cause a 10 to 20 mm Hg drop in arterial
pO2.10 (If the procedure must be performed, the
client should be intubated and mechanically
ventilated before the procedure, which should
then be accomplished with a ventilating bronchoscope.)
Nursing Alert

The smaller airway lumen in children is
further compromised by a bronchoscope that
causes some edema and can result in hypoxia.
Resuscitation equipment should be on hand
for use if needed.
The use of morphine sulfate in clients with
asthma or other pulmonary disease in which
bronchospasms are common can further exacerbate the spasms and respiratory impairment.
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The location for the procedure and the fact that
a physician will explain and perform the procedure
That the procedure requires about 30 to 45
minutes
That foods and fluids are withheld for 6 to 8 hours
before the procedure
That an analgesic, sedative, or antianxiety agent
will be administered before the procedure to
promote relaxation and alleviate potential
discomfort
That a medication can also be given before the
procedure to reduce secretions and cause the
mouth to feel dry
The type of anesthesia to be administered, usually
general for rigid bronchoscopies and local for
fiber-optic bronchoscopies
That the mouth and throat can be sprayed or
swabbed with the local anesthetic while the client
is in a sitting position, but the procedure itself is
performed in a supine position
That the local anesthetic has a bitter taste and can
cause sensations such as a thickened tongue and
difficulty in swallowing and that additional anes-

Studies

369

thetic is applied as the scope is advanced through
the airway passages
That a microscope-like instrument will be
inserted through the mouth or nose and passed
into the trachea (“windpipe”)
That the client will be able to breathe through the
nose during the procedure even though he or she
feels uncomfortable; an opportunity will be
provided for the client to practice nose breathing
with the mouth open before the procedure
That oxygen can be administered and secretions
removed via the bronchoscope
That vital signs and respiratory status will be
monitored closely during and after the procedure
and that an instrument will be attached to a finger
to monitor oxygen saturation
That, if needed, heart activity can be monitored
during and after the procedure
That measures will be provided to treat any
discomfort resulting from the procedure
Prepare for the procedure:
Obtain a history of allergies to medications or
anesthetics, known or suspected respiratory
disorders, and treatment regimen.
Ensure that dietary and fluid restrictions have
been followed before the procedure.
Ensure that, before the procedure, hematologic
status and blood clotting ability have been assessed
to include complete blood count (CBC), platelet
level, prothrombin time (PT), partial thromboplastin time (PTT), clotting time, and bleeding
time as well as arterial blood gases (ABGs).
Note and record results of electrocardiogram
(ECG), chest x-ray, and pulmonary function studies if the client is over 40 years of age and if a heart
or lung disease is present.
Remove full or partial dentures, and inform the
person performing the test whether the client has
any permanent crowns on the teeth (caps).
Remove glasses, contact lenses, or eye prosthesis if
applicable, and store in a safe place.
Provide mouth care to reduce bacterial flora in
the oral cavity.
Provide hospital gown.
Obtain and record baseline vital signs for later
comparison readings.
Have the client void.
Administer premedications SC or intramuscularly
(IM) as ordered. (Premedications can include an
analgesic such as meperidine [Demerol] to reduce
discomfort, a sedative, an antianxiety agent such
as diazepam [Valium] to promote relaxation, or
an anticholinergic such as atropine sulfate to
reduce secretions and prevent vagal stimulation
that can cause bradycardia.11)

370

SECTION II—Diagnostic

Tests and Procedures

THE PROCEDURE

The procedure varies with the type of bronchoscope and the type of anesthesia used. If needed,
cardiac monitoring and cardiopulmonary equipment should be available during both types of
bronchoscopy procedures. Specimens obtained
during the procedures should be placed in appropriate containers, properly labeled, and promptly sent
to the laboratory for cytologic or microbiologic
study.
Rigid Bronchoscopy. The client is placed in the
supine position and general anesthesia is administered. The neck is hyperextended and the lightly
lubricated bronchoscope is inserted orally and
advanced through the glottis. If necessary, the bronchoscope can be inserted via a laryngoscope. The
segments of the tracheobronchial tree accessible
with a rigid bronchoscope are visualized. The client’s
head can be turned or repositioned to aid visualization of various segments as in turning the head to
the left to evaluate the right tracheobronchial tree.12
After inspection, the bronchial brush, suction
catheter, or biopsy forceps can be introduced to
obtain tissue or sputum specimens for cytologic or
microbiologic study. Specimens can also be obtained
by bronchial washing, a procedure that entails the
instillation of small amounts of solution into the
airways and then removing it. Bronchial washing is a
useful technique for the identification of occult
malignancies and opportunistic infections in
immunocompromised clients.13 When the examination is completed, the bronchoscope is removed and
the client placed in a side-lying position with the
head slightly elevated.
Fiber-Optic Bronchoscopy. This procedure is
usually performed using local anesthesia. The client
is placed in a sitting position and the tongue and
oropharynx sprayed or swabbed with the local anesthetic. When the loss of sensation is established, the
client is placed in the supine position. The fiberoptic scope is introduced into the nose, the mouth,
an endotracheal tube, a tracheostomy tube, or a rigid
bronchoscope. The most common insertion site is
the nose. Clients who have copious secretions or
massive hemoptysis or who are more likely to have
airway complications can be intubated before the
bronchoscopy.14
Additional local anesthetic is applied through the
scope as it approaches the vocal cords and the carina,
eliminating reflex activity in these sensitive areas.
The right lung is usually examined first, followed by
the left lung. In contrast to rigid bronchoscopy, the
fiber-optic approach allows for visualization of

airway segments without having to move the client’s
head through various positions. After inspection,
specimens can be obtained for cytologic and microbiologic study. Note that fiber-optic bronchoscopies
can be performed with the aid of fluoroscopy if
biopsies of small airways or lung parenchyma are to
be obtained. When the examination is completed,
the bronchoscope is removed. The client who
receives a local anesthetic is placed in a semiFowler’s position.
NURSING CARE AFTER THE PROCEDURE

If the bronchoscopy is performed under general
anesthesia, care and assessment after the procedure
are the same as for anyone who is recovering from
this type of anesthesia.
If local anesthesia is used, maintain the client in a
semi-Fowler’s position for about 2 hours and turn
to the side as needed.
Monitor vital signs including lung sounds and
cardiac rhythm; compare with baselines, and
continually assess swallowing ability.
Administer oxygen and monitor for hypoxemia
(oxygen saturation) by means of the oximeter
attached to a finger.
Supply tissues and an emesis basin for expectoration of secretions.
If postbronchoscopy sputum samples are to be
obtained, provide the client with the appropriate
containers and instruct in the procedure to secure
the specimens.
Advise the client to refrain from smoking for
several hours after the procedure and to withhold
food and fluids for 4 to 6 hours until swallowing
ability returns.
Inform the client that activities can be resumed
when the anesthesia and medications have worn
off.
Remind the client that some soreness and possibly
hoarseness can be expected after the procedure
and that these are of short duration.
Provide warm saline gargles, throat lozenges, and
a cool compress to the neck to alleviate throat
pain or hoarseness.
Provide pencil and paper for those clients who
find it difficult to speak to enable them to
communicate.
When the gag reflex and swallowing return,
provide soft foods and warm, soothing fluids.
Encourage fluids to assist in easier expectoration
or removal of secretions.
Remind the client to report immediately any
excessive bleeding, breathing difficulty, or unusual
discomforts or sensations.
If the procedure is performed in an ambulatory

CHAPTER 16—Endoscopic

care setting, assist with arrangements for the
client’s transportation home.
Reaction to anesthetic agent or medications:
Note and report tachycardia, palpitations, hyperpnea, or hypertension. Administer ordered antihistamine. Initiate IV line and resuscitation
procedure if needed.
Persistent bleeding: Note and report amount of
excessive hemoptysis and changes in vital signs for
potential hypovolemia; caution against coughing
and throat clearing that can dislodge a clot at the
excision site and precipitate bleeding. Initiate IV
line and prepare to replace fluid loss. Prepare the
client for bronchoscopy examination to control
bleeding at the site.
Infection: Note and report elevated temperature,
yellowish or other abnormal color of sputum, or
changes in breathing pattern. Administer ordered
antibiotic therapy.
Respiratory depression, pneumothorax: Note
and report laryngospasm or bronchospasm, chest
pain, increased anxiety, dyspnea, cyanosis, audible
wheezing, stridor, or other changes in respiratory
pattern, abnormal or absent breath sounds, or
hypoxemia. Initiate oxygen and IV line. Prepare
and administer ordered medications. Arrange for
ABG monitoring. Prepare the client for chest xray. Have resuscitation and tracheostomy equipment on hand for immediate use.
Subcutaneous emphysema: Note and report
subcutaneous crepitus on the face or neck or any
changes in breathing pattern. Prepare the client
for thoracentesis. Prepare to initiate resuscitation
or tracheostomy to maintain ventilation.
Cardiopulmonary arrest, cardiac dysrhythmias:
Note and report ECG rhythm changes, chest pain,
or alterations in vital signs. Administer ordered
medications. Prepare to initiate resuscitation
procedure and secure assistance.

Studies

371

of their proximity to the aorta.15 Nodes in the left
side of the mediastinum may require biopsy by
mediastinotomy, involving a left anterior thoracotomy procedure.16
Reference Values
Normal appearance of mediastinal structures;
no abnormal lymph node tissue
INTERFERING FACTORS

None
INDICATIONS FOR MEDIASTINOSCOPY

Lack of confirmation of a diagnosis by bronchoscopy, x-ray, scan, or sputum examination17
Radiologic or cytologic evidence of carcinoma or
sarcoidosis to confirm the disease
Radiologic evidence of a thoracic infectious
process of an indeterminate nature to establish
the diagnosis of granulomatous infections, histoplasmosis, coccidioidomycosis, or tuberculosis18
Support for diagnosis of Hodgkin’s disease involving the lymph nodes19
Determination of the stage of known bronchogenic carcinoma as evidenced by the extent of
mediastinal lymph node involvement
Support for diagnosis of metastasis of a malignancy into the anterior mediastinum or
extrapleurally into the chest
Signs and symptoms of obstruction of mediastinal lymph flow in clients with a history of head or
neck malignancy, or both, to determine recurrence or spread of the cancer
CONTRAINDICATIONS

Previous mediastinoscopy that resulted in scarring and could make insertion of the scope and
biopsy of lymph nodes difficult or impossible

MEDIASTINOSCOPY
Mediastinoscopy is the direct visualization of the
structures that lie beneath the sternum and between
the lungs. These structures include the trachea, the
esophagus, the heart and its major vessels, the
thymus gland, and the lymph nodes that receive
drainage from the lungs. The procedure is
performed primarily to palpate and biopsy the
mediastinal lymph nodes through a small incision at
the base of the neck (suprasternal notch).
The lymph nodes in the right side of the mediastinum are those most accessible and safest to
biopsy with this procedure. The nodes on the left
side are more difficult to explore and biopsy because

Nursing Alert

Inadvertent puncture of the trachea, esophagus, or major blood vessels during mediastinoscopy requires an immediate
thoracotomy.
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The location for the procedure (operating room)
and the fact that a physician will explain and
perform the procedure
That the procedure requires about 1 hour

372

SECTION II—Diagnostic

Tests and Procedures

That food and fluids are withheld for at least 8
hours before and after the procedure until recovery from anesthesia
That the skin at the incisional site may be shaved
before the procedure
That a sedative is administered before the procedure to promote relaxation and an IV infusion is
started to administer fluids and medications
That general anesthesia is administered and the
client is asleep during the procedure
That a small incision is made at the base of the
neck for insertion of a microscope-like instrument to examine the structures under the breastbone and between the lungs
That the incision is sutured closed after the examination and a small dressing applied to the area
That vital signs and respiratory status are monitored closely during and after the procedure, that
an instrument will be attached to the finger to
monitor oxygen saturation, and that cardiac activity is monitored, if needed
That some chest and throat discomfort may be
experienced after the procedure and that an analgesic will be administered for these discomforts
Prepare for the procedure:
Obtain a history of allergies to medications or
anesthetics, thoracic or hematologic disorders,
and treatment regimen.
Ensure that blood typing and cross-matching are
obtained and recorded before the procedure in
the event that an emergency thoracotomy must be
performed.
Shave and prepare the site of insertion, if needed
and ordered.
THE PROCEDURE

The client is placed in a supine position and an IV
infusion is started. General anesthesia is administered via an endotracheal tube. An incision is made
at the suprasternal notch, and a path for the mediastinoscope is made using finger dissection. The
lymph nodes can be palpated at this time, followed
by insertion of the scope through the incision into
the superior mediastinum. The area is then
inspected and can be photographed for future reference and comparison. Biopsy and culture specimens
are obtained, placed in their appropriate containers,
properly labeled, and promptly sent to the laboratory. The scope is removed and the incision closed. If
the client is stable and no further surgery is immediately indicated, the endotracheal tube is removed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for anyone who is recovering from general

anesthesia, including monitoring of vital signs,
breath sounds, and comfort level.
Observe the incision site for excessive bleeding or
drainage. Assess for pain and administer analgesics accordingly.
Administer warm gargles or lozenges for throat
soreness resulting from endotracheal tube insertion for general anesthesia.
Resume any foods or fluids withheld before the
procedure, as well as other activities, when the
client has recovered from anesthesia.
Instruct the client in the observation and care of
the incision site.
Infection: Note and report elevated temperature,
yellowish or other abnormal color of sputum,
changes in breathing pattern, redness, pain,
edema, and drainage at the incision site.
Administer ordered antibiotic therapy. Perform
wound care and dressing change.
Pneumothorax: Note and report difficulty in
breathing and abnormal breath sounds or chest
pain. Administer ordered medications. Prepare
the client for portable chest x-ray for confirmation and for chest tube insertion.
Left recurrent laryngeal nerve damage: Note and
report dysphagia, hoarseness, or changes in vocal
patterns. Advise the client not to use the voice.
Provide the client with pencil and paper for
communication.
Tracheal perforation during the procedure: Note
and report subcutaneous crepitus on face or neck
or changes in breathing pattern. Provide for and
assist with resuscitation or tracheostomy.
Puncture of esophagus or major blood vessels
during the procedure: Note and report hemoptysis and amount or changes in vital signs for potential hypovolemia. Provide for post-thoracotomy
care with chest tubes in place.

THORACOSCOPY
Thoracoscopy is the direct visualization of the
thoracic cavity, which includes the examination of
the parietal and visceral pleurae, pleural spaces,
thoracic walls, mediastinum, and pericardium of the
heart. It can be undertaken as a means of performing laser procedures.20 Thoracoscopy allows more
accurate diagnosis of pulmonary conditions than
other diagnostic methods. It requires the insertion
of a chest tube connected to negative thoracic
suction and a drainage system until the lung reinflates.
INTERFERING FACTORS

None

CHAPTER 16—Endoscopic

Reference Values
Normal appearance of thoracic cavity; no
abnormality of the parietal and visceral pleurae,
pleural spaces, chest cavity wall, mediastinum,
or pericardium
INDICATIONS FOR THORACOSCOPY

Radiologic evidence of pleural effusion to establish the diagnosis of inflammatory processes
Evaluation of lung involvement in sarcoidosis
Obtaining of tissue for biopsy to support diagnosis of malignancy and size of tumor, extent of
growth, and metastasis within the thoracic cavity
Confirmation of cause or predisposing factors
associated with pneumothorax
Evidence of emphysema, empyema, or other
chronic pulmonary disease by x-ray, scan, or
sputum examination
Performance of laser procedure to reduce the size
of a tumor
CONTRAINDICATIONS

Severely compromised respiratory status caused
by obstructive or restrictive pulmonary disease
Presence of or risk for respiratory failure as indicated by ABG levels for pO2 and CO2
Nursing Alert

Respiratory distress after the procedure
requires resuscitation equipment to be on
hand.
NURSING CARE BEFORE THE PROCEDURE

Client teaching is the same as that described in the
“Mediastinoscopy” section.
The client should also be informed that a local
anesthetic may be used instead of a general anesthetic and that the incision is made in the chest
with the scope inserted through the incision to
examine the structures in the chest cavity and
possibly to obtain a biopsy.
The client should be informed that a chest tube is
inserted and connected to a suction apparatus
after the procedure and will remain in place for
about 24 hours or until the lung has reexpanded.
The client should be instructed and provided with
an opportunity to practice coughing and breathing exercises to assist with lung reexpansion and
prevent atelectasis after general anesthesia.
Physical preparation is the same as that outlined
in the “Bronchoscopy” and “Mediastinoscopy”
sections.

Studies

373

Additional diagnostic test and procedure results
should be recorded before the procedure, such as
ABGs, routine blood tests and urinalysis, and
chest x-ray and ECG for those over 40 years of age
or with cardiac or pulmonary conditions.
An IV line should be initiated to administer fluids
and medications if needed.
THE PROCEDURE

The client is positioned to expose the insertion site,
and local anesthetic is injected or general anesthetic
administered via an endotracheal tube. An incision is
made to allow insertion of the scope into the
thoracic cavity. The areas are inspected and specimens obtained or treatment performed by laser or
other method. The tissue biopsy or culture material,
or both, are placed in appropriate containers, properly labeled, and promptly sent to the laboratory. A
chest tube is inserted and connected to negative pressure suction after the scope is removed. The client is
extubated when the condition is determined to be
stable; he or she is then taken to a hospital room.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for anyone who is recovering from general
anesthesia, including monitoring of vital signs,
breath sounds, and comfort level.
Monitor the amount and color of drainage from
the chest tube, chest tube patency, and suction
functioning in removing the fluid. Assess respiratory status based on ABG determinations and
breathing.
Assist with a chest x-ray if performed to determine whether air or fluid is present in the pleural
space.
Observe the incision site for excessive bleeding or
drainage, and assess for pain and administer analgesics accordingly.
Encourage coughing and deep-breathing exercises, with splinting of the incision site.
Resume any foods or fluids withheld before the
procedure when the client has recovered from
general anesthesia.
Resume other activities after removal of the chest
tube and healing of the incision wound.
Infection (empyema): Note and report temperature elevation and changes in sputum color and
breathing pattern indicating infection. Administer
antibiotic therapy.
Hemorrhage: Note and report hemoptysis and
amount, blood loss in chest drainage bottle, or
changes in vital signs indicating hypovolemia.
Initiate IV fluid replacement. Prepare for invasive
procedure to stop bleeding, if necessary.

374

SECTION II—Diagnostic

Tests and Procedures

Figure 16–6. Esophagogastroduodenoscopy with fiber-optic endoscope.

Respiratory distress: Note and report dyspnea,
hypoxia based on ABG levels, or abnormal breath
sounds. Administer oxygen and ordered medications. Prepare for intubation and assisted ventilation.

ESOPHAGOGASTRODUODENOSCOPY
Esophagogastroduodenoscopy (EGD) is the direct
visualization of the mucosa of the upper gastrointestinal tract, which includes the esophagus, stomach, and upper duodenum, using a flexible
fiber-optic endoscope (Fig. 16–6). Any or all of the
three structures can be included in the examination
and can be referred to as esophagoscopy,
gastroscopy, or duodenoscopy, or a combination of
these, that is, esophagogastroduodenoscopy. The
upper small intestinal tract procedure, referred to as
enteroscopy, can also be performed with a longer
scope to obtain biopsies and diagnose pathologies in
this area of the tract.21
Direct visualization yields greater diagnostic data
than is possible through radiologic procedures such
as upper gastrointestinal (UGI) x-ray studies and is
gradually replacing them as the diagnostic study of
choice.22 The EGD procedure can be performed for
therapeutic as well as diagnostic purposes.
The standard flexible fiber-optic endoscope used
for EGD contains one to three channels that allow
for passage of various instruments needed to
perform therapeutic or diagnostic procedures.
Smaller endoscopes are available for use in children
and in adults in whom passage of a larger endoscope
can be difficult; however, the technical capabilities
of the instrument are often correspondingly
reduced.23

Reference Values
Normal appearance of the mucosa of the esophagus, stomach, and duodenum; no inflammation, ulceration, stricture, or other abnormality
INTERFERING FACTORS

Inability to cooperate with the procedure
Failure to follow dietary restrictions before the
procedure, although some gastric contents can be
aspirated via the endoscope
Barium swallow within the preceding 48 hours,
because the retained barium can hinder adequate
visualization
Severe UGI bleeding; blood and clots can interfere
with visualization (Gastric lavage is performed
before endoscopy in this instance.)
INDICATIONS FOR
ESOPHAGOGASTRODUODENOSCOPY

Signs and symptoms of reflux esophagitis or
esophageal strictures to confirm the diagnosis
Signs and symptoms of hiatal hernia to confirm
the diagnosis
Signs and symptoms of gastric or duodenal ulcer
to confirm the diagnosis, especially when radiologic studies yield unsatisfactory or equivocal
results
Persistent symptoms of peptic ulcer disease,
despite therapy, to determine the nature of the
problem
Bleeding from the UGI tract to determine the
source, such as esophageal varices, Mallory-Weiss
tears, peptic ulcer, stress ulcer, and stoppage of
bleeding, if possible, by sclerotherapy or coagula-

CHAPTER 16—Endoscopic

tion. (Note: If a perforated viscus is suspected,
EGD is contraindicated, and surgery is
performed.)
Suspected immunologic, anatomic, and neoplastic disorders involving the UGI tract to confirm
diagnosis through tissue biopsy24
Suspected strictures involving the antrum or
pylorus of the stomach to confirm diagnosis, with
dilatation if indicated
Diagnosis of tumors, malformation, and other
pathology of the upper small intestine
History of ingestion of a foreign body that
cannot or has not passed through the gastrointestinal system, with removal if visualized and
accessible
History of ingestion of chemicals that can injure
the esophagus or stomach to determine the extent
of damage
Suspected inflammatory or infectious process
involving the esophagus, such as Candida
esophagitis, to confirm the diagnosis through
microbiologic analysis
Evaluation of client status after surgery on the
UGI tract
Performance of endoscopic surgery with a laser
beam
CONTRAINDICATIONS

Aneurysm of the aortic arch because of the risk of
rupture during EGD instrumentation
Unstable cardiac status, because mild hypoxemia
can be induced by EGD (If it is absolutely necessary to perform the procedure, the client can be
intubated and mechanically ventilated before and
during the procedure.)
Known or suspected perforated viscus, because
the situation indicates surgery, not endoscopy,
and because endoscopic instrumentation can
further aggravate the situation
Large Zenker’s diverticulum involving the esophagus, because perforation can occur during insertion of the instrument
Suspected aortoduodenal fistula with persistent
or major bleeding, because surgical intervention
is indicated
History of dysphagia, unless previous radiologic
studies such as esophagram indicate the nature of
the problem and potential hazards involved in
passing the endoscope
Recent gastrointestinal surgery in which anastomosis can be disrupted by the insufflation of the
organ with air
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the

Studies

375

same as those described in the “Bronchoscopy”
section.
Inform the client that the procedure takes at least
1 hour, that an IV line is initiated to administer
fluid and additional medications immediately
before the procedure, and that the type of anesthesia is usually local but can be general if the
client is unduly apprehensive.
Inform the client that the instrument is inserted
through the mouth and passed into the stomach
and small intestine.
Obtain a history that includes known and
suspected gastrointestinal tract disorders, treatment regimen, and other diagnostic tests and
procedures.
THE PROCEDURE

The client is seated in a semireclining position and
the oropharynx is sprayed or swabbed with a topical
local anesthetic. Note that not all endoscopists use
local anesthesia, because it is not thought to be
necessary in the adequately sedated client.25 The
client is then assisted to the left lateral position, with
the right hand at the side, the left hand under the
pillow at the head, the neck slightly flexed, and the
knees drawn up at a right angle to the body.
Additional IV sedation can be given, usually
diazepam (Valium), at this time. Depending on
the client’s condition, vital signs and cardiac rhythm
can be monitored throughout the procedure.
Cardiopulmonary resuscitation equipment is available for use if needed. In an emergency such as
bleeding esophageal varices, EGD can be performed
at the bedside provided that cardiac status is monitored continuously and equipment is on hand for
resuscitation if needed.
A protective guard is inserted into the mouth to
cover the teeth, and a bite block can also be inserted
to maintain an open mouth without client effort or
control. The client is informed that speaking is not
possible but that breathing is not affected. Advise
the client that breathing deeply will help to allay
gagging and choking. The endoscope is then
directed through the mouth and down the pharynx.
A dental-type suction device is used to drain secretions from the mouth. The esophagus is examined,
and the scope is advanced into the stomach. If the
client retches or vomits when the scope is introduced into the esophagus, the emesis is removed by
the suction apparatus attached to the endoscope. Air
can be introduced through the endoscope to inflate
and smooth out the folds of the stomach for more
thorough visualization, and the client should be
informed that it causes a feeling of fullness or bloating. Excessive introduction of air causes client

376

SECTION II—Diagnostic

Tests and Procedures

discomfort and leads to uncontrollable belching.26
The endoscope is then advanced through the pyloric
sphincter, and the duodenum is visualized.
At any point in the examination of the organs,
accessory equipment such as a cytology brush,
biopsy forceps, and camera can be introduced to
obtain specimens or photographs. Specimens are
placed in appropriate containers, properly labeled,
and promptly sent to the laboratory. When the
examination is completed, the dental suction device
is removed, the endoscope is withdrawn, and the
tooth guard and bite block are removed.
NURSING CARE AFTER THE PROCEDURE

If the procedure is performed under general anesthesia, care and assessment are the same as for
anyone who is recovering from this type of anesthesia, including monitoring of vital signs, breath
sounds, and comfort level.
After local anesthesia, assist the client to a position
of comfort with the head slightly elevated, and
encourage the client to expectorate any accumulated secretions.
Maintain the client in a side-lying position for 1 to
2 hours to prevent aspiration of secretions.
Monitor vital signs and cardiac rhythm as well as
respiratory status, and compare with baselines.
Assess swallowing ability, site, and degree of pain
continuously.
Advise the client to withhold food and fluids for
4 to 6 hours, until swallowing ability returns.
Restrict activities until the sedative or anesthetic
has worn off and the client is awake and alert.
Provide warm saline gargles or throat lozenges to
alleviate throat discomfort.
When the gag reflex and swallowing return,
provide soft foods and warm, soothing fluids.
Remind the client that belching, bloating, or flatulence is the result of air insufflation.
Instruct the client to report immediately any
postprocedural discomfort or pain in the chest,
neck, back, or upper abdomen; pain on swallowing; difficulty in breathing; or blood expectoration.
Reaction to anesthetic agent or medications:
Note and report tachycardia, palpitations, hyperpnea, or hypertension. Administer ordered antihistamines. Initiate IV line and resuscitation
procedure if needed.
Perforation of esophagus: Note and report neck
pain or pain on swallowing, hemoptysis and
amount (bleeding at the cervical level), substernal
or epigastric pain, chest pain that increases with
breathing (bleeding at the thoracic level), or

changes in vital signs for potential hypovolemia.
Initiate IV line for fluid replacement. Prepare for
intervention to repair damaged area.
Perforation of diaphragm or stomach: Note and
report pain in the shoulder, dyspnea (diaphragm),
abdominal or back pain (stomach), or changes in
vital signs for potential hypovolemia. Initiate IV
line for fluid replacement. Prepare for intervention to repair damaged area.
Persistent bleeding: Note and report hemoptysis;
hematemesis and amounts; black, tarry stools;
or changes in vital signs for potential hypovolemia if bleeding is excessive. Initiate IV line
for fluid volume replacement or transfusion of
whole blood or packed red blood cells as
ordered.
Pulmonary aspiration: Note and report dyspnea,
cyanosis, abnormal breath sounds, hypoxemia, or
signs and symptoms of aspiration pneumonia or
pleural effusion. Maintain the client in a sidelying position and suction airway; provide resuscitation procedure as needed for immediate
interventions. Administer antibiotic therapy if
pneumonia is present.
Cardiac abnormalities: Note and report
dysrhythmias, chest pain, or alterations in blood
pressure and pulse. Administer ordered cardiac
medications. Monitor cardiac activity via ECG.

ENDOSCOPIC RETROGRADE
CHOLANGIOPANCREATOGRAPHY
Endoscopic retrograde cholangiopancreatography
(ERCP) is the visualization of the pancreatic and
biliary ducts after they have been injected with dye
(Fig. 16–7). The study involves both endoscopic and
radiologic procedures. A side-viewing flexible fiberoptic endoscope is passed into the duodenum and a
small cannula is inserted into the duodenal papilla
(ampulla of Vater), through which pancreatic juices
and bile normally drain into the duodenum.
Radiographic contrast medium is injected through
the cannula, and the pancreatic and biliary ducts are
visualized by fluoroscopic x-ray. Manometry to
measure the pressure of the ducts can be obtained by
insertion of a catheter into the channel of the scope
and placing it at the sphincter of Oddi. Another
procedure that provides visualization of the ducts is
percutaneous transhepatic cholangiography, an
invasive procedure associated with significant
morbidity.27 The ERCP procedure can be performed
for therapeutic as well as diagnostic purposes,
usually in a special endoscopy suite or in the radiology department.

CHAPTER 16—Endoscopic

Studies

377

Figure 16–7. Endoscopic retrograde cholangiopancreatography.

Reference Values
Normal appearance of the duodenal papilla on
visualization; patent common bile and pancreatic ducts when visualized by fluoroscopic x-ray;
no gallstones, strictures, or abnormal tissue
INTERFERING FACTORS

Inability to cooperate during the procedure,
although it can be performed under general anesthesia, if necessary
Failure to follow dietary restrictions before the
procedure, although some gastric and duodenal
contents can be aspirated via the endoscope
Previous surgery involving the stomach or duodenum, or both, that can cause difficulty in locating
the duodenal papilla
Barium remaining in the stomach or bowel when
a gastrointestinal series has been performed
before the procedure
INDICATIONS FOR ENDOSCOPIC RETROGRADE
CHOLANGIOPANCREATOGRAPHY

Jaundice of unknown etiology to differentiate
biliary tract obstruction from liver disease
Identification of obstruction caused by calculi,
cysts in the ducts, strictures, stenosis, and
anatomic abnormalities
Retrieval of small gallstones from the distal
common bile duct, release of strictures by dilatation within the biliary tree, performance of therapeutic procedures such as sphincterotomy

(sphincter of Oddi), and placement of biliary
drains28
Suspicion of carcinoma involving the duodenal
papilla, head of the pancreas, or biliary tract when
results of other studies such as ultrasound, scans,
or radiography are negative or inconclusive
Signs and symptoms of chronic pancreatitis to
confirm the diagnosis
Signs and symptoms of sclerosing cholangitis to
confirm the diagnosis
Persistent abdominal pain of unknown etiology
when the only alternative to ERCP is exploratory
surgery
Need to obtain tissue biopsy for cytologic analysis
CONTRAINDICATIONS

Unstable cardiopulmonary status, because ERCP
could precipitate cardiac dysrhythmias and
hypoxemia
Blood coagulation defects, especially if sphincterotomy is to be performed
Cholangitis unless the client received antibiotic
therapy before the procedure
Acute pancreatitis unless there are specific indications for the procedure such as suspicion of
hemorrhagic pancreatitis, recurrent acute pancreatitis of unknown etiology, or acute pancreatitis
caused by gallstone blockage29
Pancreatic pseudocyst except when ultrasound
and computed tomography scans have aided in
localizing the cyst and when follow-up surgery is
anticipated30
Large Zenker’s diverticulum involving the esoph-

378

SECTION II—Diagnostic

Tests and Procedures

agus because the scope can find its way into the
diverticulum and perforation can occur during
insertion of the instrument
Nursing Alert

Resuscitation equipment should be available
to treat respiratory depression with hypoxemia, cardiac complications, or adverse effects
of drugs used before and during the procedure.
NURSING CARE BEFORE THE PROCEDURE

Client teaching is the same as that described in the
“Bronchoscopy” and “Esophagogastroduodenoscopy” sections.
Inform the client that an x-ray will be taken
before the procedure and several x-ray films
during the procedure after the endoscope has
been inserted and that additional medication can
be administered to relax the sphincter of the
duodenal papilla.
Advise the client that the position will be changed
to prone after the endoscope reaches the small
intestine to accommodate the visualization of the
duodenal papilla and injection of a dye into the
ducts. Inform the client that a flushed feeling can
be experienced when the dye is injected.
Physical preparation is the same as that for a client
being prepared for bronchoscopy or esophagogastroduodenoscopy (see earlier sections).
Obtain a history that includes known or
suspected gastrointestinal disorders, treatment
regimen, information about sensitivity to iodine
to prevent possible reaction to the dye, and the
date of the last menstrual period to determine the
possibility of pregnancy to prevent exposure of
the developing fetus to x-ray.
Administer morphine sulfate instead of meperidine (Demerol) as a preprocedural medication.
THE PROCEDURE

The client is placed on an x-ray table in the supine
position and a plain film (flat plate) of the abdomen
is taken to observe for any residual contrast media
from previous studies, such as barium studies or
scans using contrast media, which can interfere with
a successful procedure. Because the client will lie on
the table for approximately 1 to 2 hours, it is desirable that the table be padded and that measures be
taken to ensure client comfort. The oropharynx is
sprayed or swabbed with a topical local anesthetic. If
an IV access such as a heparin lock or IV line has not
been established, it is done at this time. The IV access

device or line is placed in the right hand or arm
because the client will be positioned on the left side
during the procedure until the endoscope is passed
into the duodenum.31 Cardiac rhythm and pulse
oximetry for oxygen saturation and vital signs
should be monitored throughout the procedure, and
cardiopulmonary resuscitation equipment should
be available.
The client is then assisted to the left lateral position with the left arm positioned behind the back,
the right hand at the side, and the neck slightly
flexed. A protective guard is inserted into the mouth
to cover the teeth, and a bite block can also be
inserted to maintain an adequate opening of the
mouth without client effort or control. Additional
sedative and analgesic medications are administered
through the IV line at this time. The endoscope is
passed through the mouth with a dental suction
device in place to drain secretions. The scope is then
advanced down the esophagus and into the stomach.
Air can be introduced to smooth out the folds of the
stomach for better visualization of all areas. When
the endoscope reaches the duodenum, medications
such as simethicone (Mylicon) can be instilled via
the scope to reduce the bubbling caused by bile
secretions. Atropine sulfate and glucagon can be
administered through the IV line at this time to relax
the duodenum and reduce motility to allow for
cannulation of the ampulla of Vater.
The client is then turned to the prone position,
and the duodenal papilla is visualized and cannulated with a catheter. The client is requested to
remain very still during this phase of the procedure.
Occasionally the client can be turned slightly to the
right side to aid in visualization of the papilla. Dye
(contrast medium) is injected into the pancreatic
and biliary ducts via the catheter, and a series of
fluoroscopic x-ray films are taken. ERCP manometry can also be performed to measure the pressure in
the bile duct, pancreatic duct, and sphincter of Oddi
at the papilla area via the catheter as it is placed in
the area before the dye is injected.32
Specimens and biopsies for cytologic analysis can
be obtained during the procedure. These are placed
in appropriate containers, properly labeled, and
promptly sent to the laboratory. When the examination is completed, the dental suction device is
removed, the endoscope is withdrawn, and the tooth
guard and bite block are removed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as that described in the “Esophagogastroduodenoscopy” section.
Assess the ability to resume usual voiding patterns

CHAPTER 16—Endoscopic

because anticholinergics (atropine sulfate) can
cause urinary retention.
Reaction to medications or anesthetic agent:
Note and report tachycardia, palpitations, hyperpnea, hypertension, or reactions to the dye, such
as pallor, hypotension, restlessness, and diaphoresis. Administer ordered antihistamines. Initiate
resuscitation procedure if needed.
Perforation of pharynx or esophagus: Note and
report neck or chest pain, pain on swallowing,
hemoptysis, or changes in vital signs for potential
hypovolemia. Initiate IV line for fluid volume
replacement. Prepare for intervention to repair
damaged area.
Respiratory depression: Note and report breathing difficulty, apnea, cyanosis, hypoxemia,
hypotension, bradycardia, or bronchospasm.
Administer oxygen or narcotic antagonist (naloxone), if ordered. Perform resuscitation and
mechanical ventilation if needed.
Cholangitis, septicemia: Note and report
temperature elevation, upper abdominal pain,
culture results identifying Escherichia coli or
Pseudomonas spp. from release of organisms in
infected bile into the bloodstream.33 Administer
ordered antibiotic and analgesic therapy.
Acute pancreatitis: Note and report severe
epigastric and abdominal pain radiating to the
back, abdominal distention, hypoactive bowel
sounds, jaundice, or temperature elevation.
Administer ordered analgesia. Obtain blood specimen for amylase and bilirubin as levels rise in
pancreatitis, although they are usually elevated as
a result of the procedure itself from the pressure
and volume of the dye injected into the pancreatic
duct.34,35
Cardiac abnormalities: Note and report
dysrhythmias, chest pain, or alterations in blood
pressure and pulse. Administer cardiac medications. Monitor cardiac activity via ECG.

PROCTOSIGMOIDOSCOPY
Proctosigmoidoscopy is the direct visualization of
the mucosa of the anal canal (anoscopy), the rectum
(proctoscopy), and the distal sigmoid colon (sigmoidoscopy). The procedure can be performed using a
rigid or flexible fiber-optic endoscope, although the
flexible instrument is generally preferred.
Either procedure can be performed in any setting,
and a signed informed consent is not required for
anoscopy if performed as a single procedure, but it is
required for proctosigmoidoscopy if tissue is to be
removed. Some type of bowel preparation is always
needed before the procedure to clear the rectum and
sigmoid colon of feces to enhance visualization.

Studies

379

Reference Values
Normal mucosa of the anal canal, rectum, and
sigmoid colon; no polyps or other abnormal
tissue, bleeding, or inflammation
INTERFERING FACTORS

Inability to cooperate with the procedure
Severe rectal bleeding or inadequate bowel preparation
INDICATIONS FOR PROCTOSIGMOIDOSCOPY

Cancer screening with identification and polyp
removal in individuals over 40 to 45 years of age
who are asymptomatic, as part of a complete
physical examination36,37
Examination of the distal colon before a barium
enema x-ray to obtain a better view of the area38
Determination of pathology after a barium enema
x-ray with uncertain findings
Excision of tissue for cytologic analysis
Blood, pus, or mucus in the feces, or a combination of these conditions, to determine the cause of
the problem, such as inflammatory bowel disease
Determination of the cause of pain or tissue
prolapse on defecation to determine the cause of
the problem, such as rectal prolapse, abscess,
fistula, or fissure
History of rectal itching, pain, or burning to
determine the cause of the problem, such as
hemorrhoids
Signs and symptoms of diverticular disease involving the sigmoid colon to confirm the diagnosis
Signs and symptoms of Hirschsprung’s disease
and colitis in children to confirm the diagnosis
Treatment to reduce volvulus of the sigmoid
colon
Removal of hemorrhoids by laser therapy
CONTRAINDICATIONS

Suspected bowel perforation, acute peritonitis,
acute fulminant colitis, diverticulitis, toxic megacolon, or ischemic bowel necrosis
Severe cardiopulmonary disease
Large abdominal aortic or iliac aneurysm
Severe bleeding or blood coagulation abnormality
Advanced pregnancy
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The location for the procedure and the fact that a
physician will perform the procedure
That the procedure requires about 15 to 30
minutes

380

SECTION II—Diagnostic

Tests and Procedures

Nursing Alert

A preparation that includes a laxative or
enemas should not be administered to pregnant women or clients with inflammatory
colon diseases unless the physician is notified
and special orders are obtained.

That a light meal the evening before and liquids
the morning of the procedure are allowed
That a laxative and enema can be administered
the night before and that two sodium phosphatesodium biphosphate (Fleet) small-volume
enemas can be given 1 hour before the procedure
to remove feces for better visualization (This
instruction varies with physician or hospital
depending on the procedure to be performed and
whether it is performed in conjunction with other
studies, such as barium enema x-ray.)
That the client will be placed in a knee–chest position for the rigid proctoscopic examination or a
left lateral position for the flexible fiber-optic
procedure; that drapes will be used to avoid exposure and prevent embarrassment; and that the
lubricated scope will be inserted into the rectum
after the physician performs a digital rectal examination
That the urge to defecate can be experienced
when the scope is inserted; that slow, deep breathing through the mouth can help to alleviate this
feeling; that the client will be allowed to practice
this breathing technique beforehand
That specimens can be obtained and suctioning
performed through the scope to remove excess
materials during the examination to enhance
visualization
That slight rectal bleeding can be experienced
after the procedure if polyps or tissue is excised
but that it should not persist for longer than 2
days
Prepare for the procedure:
Obtain a history of bowel disorders, pregnancy
status, and blood studies that indicate a coagulation disorder.
Ensure that dietary and fluid restrictions have
been followed (light meal in the evening and
liquids in the morning before the procedure).
Ensure that bowel preparation has been implemented (laxatives or enema, or both, in the
evening and one or two enemas in the morning
before the study).
Provide the client with a hospital gown to wear as
needed.
Have the client void.

Obtain and record baseline vital signs for later
comparison readings.
THE PROCEDURE

Depending on the type of instrument to be used, the
client is assisted to either the left lateral position with
the buttocks at or extending slightly beyond the edge
of the examination table or bed (fiber-optic scope)
or the knee–chest position on a special examining
table that tilts the client into the desired position
(rigid scope). The client is draped for warmth and
privacy.
After visual inspection of the perianal area, a
preliminary digital rectal examination is performed
with a well-lubricated gloved finger. A fecal specimen can be obtained from the glove when the finger
is removed from the rectum. A lubricated anoscope
is then inserted and the anal canal inspected
(anoscopy). The anoscope is then removed, and a
lubricated proctoscope or flexible sigmoidoscope is
inserted. The lubricant is used to ease passage of the
scope and decrease discomfort. The scope is manipulated gently to facilitate passage, and air can be
injected to improve visualization. Inform the client
that this portion of the procedure can cause flatus to
be expelled. Suction and cotton swabs are used to
remove excess blood, mucus, or liquid feces that can
hinder visualization. Examination also takes place as
the scope is gradually withdrawn. Specimens of
tissue or exudate can be obtained, polyps excised, or
photographs taken via accessories to the endoscope.
Additional examination of the rectal and anal areas
can also be performed. When the examination is
completed, the scope is completely withdrawn and
residual lubricant is cleansed from the anal area.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to the supine position and
allowing him or her to rest for a few minutes or as
needed.
Take vital signs and compare with preprocedure
readings.
Gradually assist the client to a sitting position to
avoid possible orthostatic hypotension. Take vital
signs again, and report to the physician any
changes from the baselines.
Assist the client in cleansing any remaining lubricant from the anal area with commercial wipes or
mild soap and warm water, if needed.
Provide a sitz bath that can soothe and relieve
discomfort.
Remind the client that slight rectal bleeding or
blood in the stool can be noted for up to 2 days.
Instruct the client to report to the physician any

CHAPTER 16—Endoscopic

abdominal pain or distention or pain on defecation.
Persistent bleeding: Note and report amount of
bleeding from the rectum or changes in vital signs
for potential hypovolemia. Prepare for procedure
to control bleeding at the biopsy or polyp removal
site.
Colon perforation: Note and report abdominal
pain and distention, fever, or mucopurulent
drainage or bleeding from the rectum. Initiate IV
line. Prepare the client for surgical repair of the
colon.

COLONOSCOPY
Colonoscopy is the direct visualization of the
mucosa of the entire colon and terminal ileum by
means of a flexible fiber-optic colonoscope (Fig.
16–8). Fluoroscopy can be used to assist in guiding
the advancement of the scope.39 Colonoscopes used
for this procedure vary in length, depending on the
extent of the colon to be examined and the size and
age of the client, with more than 20 different types of
scopes available commercially.40 When the colonoscope has been inserted as far as the cecum, nearly
the entire tube is contained within the colon.41 The
procedure is similar to that for a proctosigmoidoscopy, except that it takes longer to perform (as
long as 2 or more hours).
Reference Values
Normal intestinal mucosa with no polyps or
other abnormal tissues; no bleeding or inflammation

Studies

381

INTERFERING FACTORS

Inability to cooperate with the procedure
Severe gastrointestinal bleeding or inadequate
bowel preparation
INDICATIONS FOR COLONOSCOPY

Signs and symptoms of lower gastrointestinal
disorders, especially when barium enema x-rays
and proctosigmoidoscopy have failed to provide a
definitive diagnosis
Determination of the cause of rectal bleeding,
such as in polyps, diverticular disease, cancer,
vascular abnormalities, with possible hemostasis
by coagulation
Suspicion of cancer involving any part of the
colon
Follow-up of clients previously treated for cancer
of the colon
Follow-up of clients who have had surgery for
recurrence of polyps or lesions
Signs and symptoms of inflammatory bowel
disease such as Crohn’s disease, ulcerative colitis,
infectious colitis
Follow-up of clients who have previously received
radiation therapy to detect radiation colitis
Further evaluation and sclerosis of strictures in
the colon by laser if needed
Evaluation or diagnosis of Hirschsprung’s disease
in children
Evaluation of clients with endometriosis, which
can involve the colon in 30 to 35 percent of those
examined
Removal of polyps and foreign bodies from the
colon
Reduction of sigmoid volvulus and intussusceptions of the colon42
CONTRAINDICATIONS

Suspected bowel perforation, acute peritonitis,
acute fulminant colitis or other type of colitis,
ischemic bowel necrosis
Recent bowel surgery
Advanced pregnancy
Severe cardiac or pulmonary disease
Recent myocardial infarction
Known or suspected pulmonary embolus
Large abdominal aortic or iliac aneurysm
Severe bleeding or blood coagulation abnormality
NURSING CARE BEFORE THE PROCEDURE

Figure 16–8. Colonoscopy with fiber-optic endoscope.

Client teaching is the same as that described in the
“Proctosigmoidoscopy” section.
Inform the client that the procedure requires 30 to

382

SECTION II—Diagnostic

Tests and Procedures

Nursing Alert

A preparation that includes a laxative or
enemas should not be administered to pregnant women or to clients with inflammatory
colon disease unless the physician is notified
and special orders are obtained.
60 minutes to complete and that meals should
consist of a clear liquid diet for 24 to 48 hours
before the examination.
Inform the client that bowel preparation consists
of a laxative during the late afternoon of the day
before the procedure and that warm tap water or
saline enemas until clear are administered 2 hours
before the procedure.
Medications are administered to promote relaxation, alleviate potential discomfort, and reduce
secretions 30 minutes before the procedure, and
an IV line can be started to administer fluids and
additional medications for sedation and relaxation before insertion of the scope.
Obtain history of bowel, anal, or rectal disorders;
blood coagulation disorder; pregnancy status; and
medications such as aspirin or iron preparation
taken 1 week before the procedure, because such
medications affect blood clotting and cause black,
sticky stool that is difficult to remove with bowel
preparation.
Ensure that hematologic status and blood clotting
ability have been assessed to include CBC, platelet
level, PT, PTT, clotting time, and bleeding time
before the procedure.
Ensure that clients with heart valve disorders have
had prophylactic antibiotic therapy.
Ensure that client follows dietary and fluid restrictions of a liquid diet for 24 to 48 hours before the
study and ingests no solid foods for at least 2
hours before oral bowel preparation.
Ensure that the bowel preparation has been
implemented. (This includes 1 day of oral bowel
preparation except in those clients with ulcers,
colitis, or obstructions or in children. It also
includes administering laxatives or enemas, or
both, until clear and free from any solid material.)
Initiate an IV line or venous access device if
ordered.
Provide a hospital gown.
Have the client void.
Obtain and record baseline vital signs for later
comparison readings.
Administer premedications SC or IM as ordered.
(Premedications can include an analgesic such as
meperidine [Demerol] to reduce discomfort, a
sedative or an antianxiety agent such as diazepam

[Valium] to promote relaxation, or an anticholinergic such as atropine sulfate to reduce secretions.)
THE PROCEDURE

The client is assisted to the left lateral position and
draped for privacy with the buttocks exposed. Every
effort should be made to prevent client embarrassment. Cardiac monitoring and cardiopulmonary
resuscitation equipment are available during and
after the procedures. If an IV access such as a
heparin lock or an IV line has not been established,
it is made at this time in the right hand or arm
because the client is positioned on the left side
initially. Additional sedation such as diazepam
(Valium) can be administered through the IV at this
time. After visual inspection of the perianal area, a
preliminary digital rectal examination is performed
with a well-lubricated finger. Before insertion into
the anus, the fiber-optic colonoscope is well lubricated to ease passage of the scope and reduce
discomfort. The client is requested to bear down as
the scope is advanced into the rectum to ease passage
of the tube. Gentle abdominal pressure can be
applied as the scope is advanced through the
sigmoid colon. As the transverse colon is entered, the
client can be assisted to the supine position to facilitate passage of the scope. Small amounts of air can
be insufflated throughout the procedure to aid in
visualization, and sometimes air is removed to
promote passage of the scope. The client should be
informed that this practice can cause flatus during
and after the study. Abdominal pressure can be
applied again when the scope reaches the splenic
flexure. As the scope reaches the hepatic flexure, the
client is requested to take deep breaths to aid in the
movement of the scope downward through the
ascending colon to the cecum. Finally, the scope is
inserted into the terminal portion of the ileum.43
The bowel lumen is studied as the scope is withdrawn and, if indicated, biopsy specimens, cultures,
and smears are obtained and polyps or foreign
bodies removed. Photographs can also be taken for
future reference. Tissue samples are placed in appropriate containers, properly labeled, and promptly
sent to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
assisting the client to a position of comfort and
allowing time to rest.
Take vital signs and compare them with preprocedure readings to assess for changes caused by
vasovagal reflex and other complications as
outlined later in this section.

CHAPTER 16—Endoscopic

Monitor respiratory status and cardiac rhythm as
well as comfort level, and report changes to the
physician.
Provide a sitz bath to relieve discomfort.
Restrict foods and fluids for approximately 2
hours after the procedure as well as activities until
the sedation has worn off.
Discontinue the IV line or access device when the
client is stable.
Remind the client that slight bleeding can cause
blood in the feces for about 2 days if polyps or
biopsy tissues have been excised and to report
immediately any abdominal pain, excessive bleeding, fever, or unusual sensations.
Reactions to medications: Note and report
changes in vital signs (hypotension and bradycardia) or respiratory depression (cyanosis, changes
in breathing pattern, and breath sounds).
Administer ordered antihistamines and other
medications. Initiate oxygen administration or
resuscitation procedure as needed.
Postcolonoscopy distention syndrome: Note and
report abdominal distention and cramping from
air injected into the bowel during the procedure.
Insert rectal tube, perform position changes, and
encourage walking with assistance.
Hemorrhage: Note and report excessive and
persistent bleeding from the rectum if polyps
were removed or biopsy was performed. Also note
and report increased pulse and decreased blood
pressure or grossly bloody feces. Initiate IV line
for fluid volume replacement or blood transfusion as appropriate.
Colon perforation: Note and report abdominal
pain, distention, and rigidity or fever. Administer
ordered medication. Prepare the client for possible surgical repair of the colon.
Cardiac dysrhythmias, myocardial infarction:
Note and report chest pain or changes in pulse
rate and rhythm. Monitor cardiac activity via
ECG. Initiate IV line and administer ordered
medications.

CYSTOSCOPY
Cystoscopy is the direct visualization of the urethra,
urinary bladder, and ureteral orifices by means of a
rigid cystoscope inserted through the urethra (Fig.
16–9). It contains an obturator to assist in the insertion (which is removed after the scope is in place)
and a telescope with a lens and light system. Flexible
fiber-optic cystoscopes are also available and are
used in different sizes and varieties depending on the
reason for the procedure. The purpose of cystoscopy
is primarily to diagnose pathological conditions, but

Studies

383

Figure 16–9. Cystourethroscopy.

it can also be therapeutic to perform or evaluate
treatment protocols. The procedure allows a view of
areas not usually observable with x-ray procedures,
and it can be performed with or after ultrasonography or radiography.
Reference Values
Normal urethra, bladder, and ureters; no polyps
or other abnormal tissues, inflammation or
bleeding, or strictures or anatomic abnormalities

INTERFERING FACTORS

None
INDICATIONS FOR CYSTOSCOPY

Inspection of the lower urinary tract when radiologic studies are abnormal or inconclusive, especially flat plate and excretory urography, to
diagnose the problem
Differentiation of benign and malignant lesions
involving the bladder through tissue biopsy and
laboratory analysis
Evaluation of changes in urinary elimination
patterns that include frequency, nocturia, urgency,
dysuria, dribbling, hesitancy, and incontinence
Hematuria of unknown etiology to determine the
source of the problem
Persistent urinary tract infections (UTIs) that do
not respond to medications to determine the
source of the problem
View of the urethra and neck of the bladder area
to identify prostatic hyperplasia and degree of
obstruction and to perform transurethral prostatectomy
Identification of tumors, polyps, congenital
anomalies such as duplicate ureters, ureteroceles,
urethral or ureteral strictures, diverticula, and
areas of inflammation or ulceration

384

SECTION II—Diagnostic

Tests and Procedures

Removal of small renal calculi from the bladder or
ureters
Removal of polyps and small tumors (including
fulguration) from the bladder
Evaluation of function of each kidney by obtaining urine samples from each ureteral catheter
Dilation of strictures of the urethra or ureters
Placement of ureteral catheters (ureteroscopy) to
drain urine from the renal pelvis or for retrograde
pyelography; placement of ureteral stents before
surgical procedures such as colon resection
Evaluation of blood clots and fulguration of
bleeding sites within the lower urinary tract
Implantation of radioactive seeds into bladder
tumors
CONTRAINDICATIONS

Bleeding disorders, because use of instrumentation can lead to excessive bleeding from the lower
urinary tract
Acute cystitis or urethritis, because instrumentation can allow bacteria to enter the bloodstream
and cause septicemia
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The location for the procedure (cystoscopy suite)
That a physician will perform the procedure
That the study can take 30 minutes or more,
depending on the purpose and type of procedures
to be performed, such as retrograde pyelogram or
transurethral prostatectomy
That food and fluids are withheld for 8 hours
before the procedure if general or spinal anesthesia is used and that intake is restricted to clear
fluids for 8 hours before the procedure if local
anesthesia is used
That an anesthetic will be administered, such as
local, general, or spinal, depending on the age of
the client and the procedure to be performed
That, to prevent infection, an antibiotic can be
administered before and after the procedure
That a special microscope-like instrument will
be inserted into the urethra to visualize the bladder
That, if a local anesthetic is administered, a sensation of pressure, a need to void, or both can be
experienced as the procedure is performed
That, if general anesthesia is to be used, the client
will be instructed in deep-breathing technique
and other postoperative activities and that time
will be allowed to practice techniques
That vital signs and urinary output will be monitored closely after the procedure
That, if a transurethral prostatectomy is perfor-

med, a catheter will remain in place, possibly an
with an irrigation system attached
That a burning sensation or discomfort on urination can be experienced during the first few voidings and that the urine will be blood-tinged for
the first and second voidings after the procedure
Prepare for the procedure:
Obtain history of genitourinary infections, bleeding disorders, or other disorders of the urinary
tract.
Ensure that hematologic status and blood clotting
ability have been assessed to include CBC, platelet
count, PT, PTT, and urinalysis results for abnormal results.
Ensure that dietary and fluid restrictions have
been followed based on the type of anesthesia to
be administered.
Administer enema if ordered.
Provide a hospital gown.
Have client void.
Obtain and record baseline vital signs for later
comparison readings.
Administer ordered antibiotic therapy.
Administer premedications SC or IM as ordered,
depending on the type of anesthesia to be used.
Such premedications include meperidine (Demerol) to promote relaxation and atropine sulfate
to decrease secretions.
THE PROCEDURE

The client is positioned on the special cystoscopy
table with the legs placed in stirrups and draped for
privacy. A general or spinal anesthetic is administered
before positioning. The external genitalia are cleansed
with an antiseptic solution. If a local anesthetic is
used, it is instilled into the urethra and retained for
5 minutes. A penile clamp can be used for male
clients to aid in the retention of the anesthetic.
The cystoscope alone can be used for the examination or an urethroscope can be used to examine
the urethra before the cystoscopy. The urethroscope
has a sheath that can be left in place and the cystoscope inserted through it, avoiding the need for
multiple instrumentation. After the insertion of the
cystoscope, any urine remaining in the bladder can
be drained or a sample of residual urine can be
obtained for culture or other analyses. The bladder is
irrigated using an irrigation system attached to the
scope, usually with sterile water unless an isotonic
solution such as mannitol is used during the
transurethral resection procedure. An isotonic solution is used because of the possibility of the solution’s entering the circulation. Solution instilled into
the bladder aids in visualization to ensure thorough
examination.

CHAPTER 16—Endoscopic

If a tumor is found, it can be biopsied by use of a
cytology brush or biopsy forceps inserted through
the scope. A tumor that is small and localized can be
excised and fulgurated. This procedure is termed
transurethral resection of the bladder (TURB).
Polyps can also be excised if identified.
Other procedures that can be performed via the
cystoscope are fulguration of ulcers or bleeding sites
using electrocautery, crushing and removal of small
renal calculi from the ureters or bladder, dilation of
ureteral or urethral strictures, and instillation of
chemotherapeutic agents. Ureteral catheters can
also be inserted to obtain urine samples from each
kidney for comparative analysis and radiologic studies.
On completion of the examination or treatments,
or both, the cystoscope is withdrawn, the legs
lowered from the stirrups, and the supine position
assumed. Any specimens obtained are placed in the
appropriate container, properly labeled, and
promptly sent to the laboratory.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for anyone who is recovering from general
anesthesia and include monitoring vital signs, breath
sounds, and comfort level.
If a local anesthetic has been administered, allow
the client to rest in the supine position for several
minutes, and then assist him or her from the table.
Assess for the resumption of normal voiding
patterns, the time and amount of voiding, and the
appearance of the urine.
If bladder spasms occur, administer an anticholinergic.
Administer an analgesic such as phenazopyridine
(Pyridium) for dysuria caused by edema, and
provide warm sitz or hip baths for adults or tub
baths for children.
Resume foods and fluids withheld before the
procedure and, if not medically contraindicated,
encourage fluid intake.
Remind the client to report flank or suprapubic
pain, persistent blood-tinged or bloody urine, any
persistent difficulty or change in urinary pattern,
or fever and chills.
UTI: If bacteremia is suspected, note and report
burning on urination; voiding frequency; cloudy
or foul-smelling urine, or both; positive culture
results; or chills and fever. Administer antimicrobial therapy as ordered. Increase fluid intake to
3000 mL within 24 hours of the procedure to
dilute the urine. Instruct the client as to which
foods and medications irritate the bladder and
which fluids promote an acidic urine.

Studies

385

Urinary retention: Note and report dribbling,
hesitancy, frequency of small amounts of urinary
output, or bladder distention. Prepare for
catheterization for residual. Administer cholinergic such as bethanechol (Urecholine) to stimulate
contraction of the bladder. Increase fluid intake to
3000 mL, if appropriate, and monitor intake and
output for at least 24 hours after the procedure.
Hemorrhage: Note and report hematuria (excessive and persistent) and amount if biopsy was
performed; report changes in vital signs indicating hypovolemia. If biopsy was performed, maintain bed rest for 4 hours, if possible.
Bladder perforation: Note and report suprapubic
pain or excessive hematuria. Administer ordered
medications. Prepare for surgical repair.
Ureteral or urethral catheter obstruction: Note
and report drainage difficulty. Maintain patency
and connection to a closed collecting system.
Avoid kinking or tension on catheter. Irrigate only
with order, using proper amount of solution
based on type of catheter. Maintain sterile closed
system, and provide catheter insertion site care as
appropriate.

COLPOSCOPY
Colposcopy is the direct visualization of the vagina
and cervix by means of a special binocular microscope and light system. It allows for accurate diagnostic findings in the prevention of cancer as well as
in the identification and extent of cervical lesions.
Another source of detection of cervical pathology is
cervicography, a photograph of the cervix that can
be made during routine gynecologic examinations
or with colposcopy. The photographs are made into
slides that allow visualization of the entire cervix
and can be used with or without other tests to detect
malignancy.44
Colposcopy can be an alternative to cone biopsy
(conization) of the cervix, a surgical procedure. If
the results of the biopsy obtained from colposcopy
are inconclusive, the conization is performed.
Reference Values
Normal appearance of the vagina and cervix; no
abnormal cells or tissues
INTERFERING FACTORS

Inability to cooperate with the procedure
Failure to adequately cleanse the cervix of secretions and medications

386

SECTION II—Diagnostic

Tests and Procedures

Heavy menstrual flow
Scarring of the cervix
INDICATIONS FOR COLPOSCOPY

Abnormal Papanicolaou (Pap) smear to determine presence of malignant cells
Schiller test positive for abnormal cells
Identification of existing lesions and monitoring
of postsurgical removal of lesions
Monitoring for the development of cancer in
women whose mothers took diethylstilbestrol
during pregnancy
Localization of the area from which cervical
biopsy samples can be obtained because such
areas are not always visible to the naked eye
Evaluation of the male genitalia for diagnosis of
sexually transmitted diseases (STDs), condylomata, and papillomavirus45
CONTRAINDICATIONS

Bleeding disorders, especially if cervical biopsy
specimens are to be obtained
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The location for the procedure and the fact that a
physician or nurse practitioner will perform the
procedure
That the procedure should take about 15 minutes
That there are no food or fluid restrictions
That a vaginal speculum will be inserted to visualize the cervix, causing only slight discomfort,
followed by clearer visualization through the
speculum with a microscope-like device focused
on the cervix
That a small sample of cervical tissue will be
obtained, causing slight discomfort and a minimal amount of bleeding, for laboratory analysis
Prepare for the procedure:
Ensure that the client is not menstruating at the
time of the procedure.
Obtain a history of the last menstrual period,
because the procedure is best performed 1 week
after the end of a period. Also obtain the results of
blood clotting laboratory tests such as CBC,
platelet count, PT, or PTT.
Provide a gown or drape as appropriate.
Have the client void immediately before the
procedure.
THE PROCEDURE

The client is placed on the gynecologic examination
table, legs flexed at the knees, or placed in stirrups
and draped for privacy as for a routine pelvic examination. The external genitalia are cleansed with an

antiseptic solution, and a lubricated metal or plastic
speculum is inserted into the vagina. Water is used as
a lubricant if a Pap smear is also to be collected.
For colposcopy, the cervix is swabbed with 3
percent acetic acid to remove mucus or cream
medications and to improve the contrast between
tissue types. The scope is positioned at the speculum
and is focused on the cervix (the scope itself is not
inserted into the vagina). The client is advised to
relax and control breathing to reduce any discomfort
during the procedure. The area is carefully examined
using light and magnification. Photographs can be
taken for future reference.
Tissues that appear abnormal, such as whitish
epithelia (leukoplakia) or atypical or irregular blood
vessels, are biopsied with forceps inserted through
the speculum. The samples are placed in appropriate
containers with a special preservative solution, properly labeled, and promptly taken to the laboratory.
Bleeding, not uncommon after cervical biopsy, can
be controlled by cautery, suture, or application of
silver nitrate or ferric subsulfate to the site. The
vagina is rinsed with sterile saline or water to remove
the acetic acid and prevent burning after the procedure. If bleeding persists, a tampon can be inserted
by the physician after removal of the speculum.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
cleansing the excess lubricant, solutions, or secretions from the perineal area.
Assist the client to slowly assume a sitting or
standing position and to dress. If cramping
occurs, administer a mild analgesic.
If a biopsy was performed and a vaginal tampon
inserted, inform the client as to when it can be
removed (usually 8 to 24 hours) and that pads can
be worn afterward if there is bleeding or drainage.
Inform clients who have had a biopsy procedure
that a gray-green vaginal discharge can persist for
a few days to a few weeks, that strenuous exercise
should be avoided for 8 to 24 hours, and that
douching and intercourse should be avoided for 2
weeks or as otherwise directed by the physician.
Remind the client to report excessive vaginal
bleeding or abnormal vaginal discharge, abdominal pain, or fever to the physician.
Hemorrhage: Note and report excessive or
persistent vaginal bleeding if biopsy was
performed. Also note and report changes in vital
signs. Weigh pads to determine blood loss.
Pelvic inflammation: Note and report abdominal
pain or fever. Administer ordered antibiotic and
analgesic therapy. Remind client to avoid douching or intercourse for 2 weeks.

CHAPTER 16—Endoscopic

Studies

387

Figure 16–10. Culdoscopy.

CULDOSCOPY
Culdoscopy is the direct visualization of the cul-desac of Douglas by means of a culdoscope, a rigid
endoscope that is introduced through a small incision in the posterior vaginal fornix (Fig. 16–10). The
procedure permits visualization of the pelvic
surfaces of the sigmoid colon and rectum, pelvic
ligaments, fallopian tubes, ovaries, and uterus. It has
been largely replaced by laparoscopy (see following
section), a procedure that provides a wider field of
view with less risk of infection. It can still be used,
however, for very obese women.46
Reference Values
Normal appearance of ovaries, fallopian tubes,
uterus, and pelvic ligaments; normal appearance
of pelvic surfaces of sigmoid colon and rectum
INTERFERING FACTORS

Inability to assume the knee–chest position
Presence of pelvic adhesions
INDICATIONS FOR CULDOSCOPY

Suspected ectopic pregnancy or tubal abnormalities leading to fertility problem in obese clients
who are not candidates for laparoscopy
Pelvic pain or masses of unknown etiology
Tubal ligation procedure in obese clients
CONTRAINDICATIONS

Acute infections involving the vulva or vagina

Acute peritonitis
Pelvic masses that involve the cul-de-sac of
Douglas
NURSING CARE BEFORE THE PROCEDURE

Client teaching is the same as that described in the
“Colposcopy” section.
Inform the client that foods and fluids are withheld for 6 to 8 hours before the procedure.
Inform the client that a local or spinal anesthesia
will be used and that medications will be administered by injection before the procedure to
promote relaxation and comfort.
Explain that a small incision will be made in the
vaginal wall and the scope inserted through the
vagina into the pelvic cavity to examine the
organs but that no sutures are required to close
the incision, which usually heals within 1 week.
Prepare for the procedure:
Provide a hospital gown.
Administer enema or vaginal irrigation, or both,
as ordered.
Perform partial perineal shave as ordered.
To provide venous access during the procedure,
initiate an IV line or access device such as a
heparin lock if ordered.
Obtain and record baseline vital signs for later
comparison readings.
Have the client void.
Administer premedications SC or IV as ordered,
such as an analgesic (meperidine [Demerol]) and
a sedative (diazepam [Valium]).

388

SECTION II—Diagnostic

Tests and Procedures

THE PROCEDURE

AMNIOSCOPY

The client is placed on the operating room table in a
supported knee–chest position and draped for
privacy. The table is tilted to shift the abdominal
contents toward the diaphragm. If a spinal anesthesia is used, it is administered before the client is
placed in this position. If a local anesthesia is used, it
is injected into the posterior vaginal fornix either
before or after the knee–chest position is assumed. A
vaginal speculum or retractors are inserted into the
vagina to provide visualization of the posterior
fornix. A small incision is made in the posterior
vaginal wall, and the culdoscope is inserted into the
vagina and through the incision. The pelvic organs
are examined with the microscope-like instrument
and therapeutic procedures are completed. The
scope is then removed. No sutures are required to
close the incision.

Amnioscopy is the direct visualization of the amniotic fluid by means of an amnioscope inserted into
the cervical canal after dilatation of the cervix. The
procedure allows visualization of the amniotic fluid
through the intact membrane to detect and evaluate
meconium staining. Meconium in the amniotic fluid
is an indication of fetal distress.48 Blood samples can
also be obtained through the amnioscope from the
scalp of the fetus to determine pH level, oxygen,
carbon dioxide, and bicarbonate levels if fetal
distress is suspected.49

NURSING CARE AFTER THE PROCEDURE

INTERFERING FACTORS

Care and assessment after the procedure include
assisting the client to the supine position and allowing her time to rest.
Take vital signs and compare them with baselines.
Cleanse the perineal area of any blood and apply
a clean perineal pad.
Resume foods, fluids, and activities when the
client has stabilized, the sedative has worn off, and
no signs of complications exist.
Administer a mild analgesic to alleviate any
discomfort.
Inform the client that a small amount of “spotting” can occur for 1 to 2 days and that a pad can
be worn after the procedure.
Instruct the client to refrain from douching or
intercourse for 2 weeks or as directed by the
physician.
Remind the client to report to the physician any
excessive vaginal bleeding, blood in the feces or
urine, fever, or unusual discomfort.
Hemorrhage: Note and report amount of excessive vaginal bleeding and change in vital signs,
which includes increased pulse and decreased
blood pressure. Weigh pads to determine blood
loss. Initiate IV line to replace fluid volume loss.
Pelvic infection: Note and report fever or abdominal pain. Administer ordered analgesic and
antibiotic therapy. Remind client to refrain from
douching or intercourse for 2 weeks.
Rectal, bladder, or intestinal perforation: Note
and report abdominal pain or blood in urine or
feces. Administer ordered medication. Prepare
client for possible surgical repair.47

Reference Values
Normal amniotic fluid color with no meconium
staining

None
INDICATIONS FOR AMNIOSCOPY

To evaluate for possible fetal hypoxia by noting
change in color of amniotic fluid caused by
passage of meconium from the rectum of the
fetus
To secure a fetal scalp blood sample to determine
fetal acid–base and blood gases status in the diagnosis of fetal hypoxia and distress
CONTRAINDICATIONS

Clients who are in active labor
Clients with ruptured membranes
Clients with cervical infection or STD such as
gonorrhea
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The location for the procedure
That a physician will explain the benefits, risks,
and precautions taken during the procedure to
prevent complications
That the procedure requires 15 minutes
That food and fluid are not restricted nor will
medications be administered before the procedure
That an amnioscope is inserted into the dilated
cervical canal to view the amniotic sac to evaluate
the color of the fluid and obtain a blood sample
from the scalp of the fetus
That pressure is applied to the puncture site and
that no fluid will be removed

CHAPTER 16—Endoscopic

That some discomfort is experienced during the
procedure
Prepare for the procedure:
Obtain history for presence of cervical or vaginal
infections or other abnormalities to report before
the procedure.
Provide a gown or drape as appropriate.
Have client void immediately before the procedure.
THE PROCEDURE

The client is placed in the lithotomy position with
the legs supported in stirrups and draped for
privacy. The external genitalia are cleansed with an
antiseptic solution and the vaginal speculum is
inserted. The cervix is dilated to 2 cm, and the scope
is inserted into the cervical canal. The amniotic sac
is viewed with the lighted amnioscope for color.
Fluid is not removed from the sac for analysis.
If a fetal scalp blood sample is to be obtained, the
fetal scalp is cleansed with an antiseptic through the
scope and gently dried. A small amount of petrolatum is placed on the scalp, and the skin of the scalp
is pierced with a small lancet. The fetal blood beads
on the site with the assistance of the petrolatum, and
a long capillary tube collects the blood. Firm pressure is applied to the puncture site, and the capillary
tube is sealed with wax, placed on ice, and promptly
labeled and sent to the laboratory.50
The amnioscope is removed after the examination
or collection of the specimen, and a perineal pad is
applied, if needed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
cleansing the perineal area, assisting the client in
removing her legs from the stirrups, and allowing
her time to rest in the supine position.
Assess uterine contractions, and, if a scalp specimen has been obtained, assess the fetus for condition at the site and apply an antibiotic ointment.
Remind the client that some vaginal and cramping discomfort can be experienced for 24 hours
after the procedure.
Inform the client that excessive pain or rupture of
membranes should be reported immediately.
Premature membrane rupture: Note and report
amniotic fluid leakage and amount of loss. Assess
contractions. Provide pads. Instruct to avoid
walking and to report any changes in contractions. Provide support to allay anxiety.
Bleeding from fetal scalp puncture: Note and
report condition of the site and presence of
hematoma or other abnormality.

Studies

389

LAPAROSCOPY
Laparoscopy is the direct visualization of the
abdominal and pelvic contents by means of a rigid
laparoscope that is introduced into the body cavity
through a small periumbilical incision about 1 to 2
cm in length. The procedure has replaced the laparotomy as a method of diagnosis and treatment of
abdominal and pelvic organ disorders. Three types
of laparoscopies can be performed: (1) gastrointestinal, (2) gynecologic, and (3) those associated with
surgical procedures such as vaginal hysterectomy,
cholecystectomy, or splenectomy.
Gastrointestinal laparoscopy, also known as peritoneoscopy, allows for viewing of the liver, gallbladder, spleen, and stomach (greater curvature) after
insufflation with nitrous oxide.51 It is performed on
a special endoscopy table that can be tilted to various
positions to improve visualization. Figure 16–11
depicts a typical gastrointestinal laparoscopy with
the scope positioned in the pneumoperitoneum.
Premedication with sedatives and analgesics as well
as the local anesthetic injection are administered to
minimize discomfort associated with the procedure.52
Gynecologic laparoscopy, also known as pelviscopy, is performed to view the ovaries, fallopian
tubes, and uterus within the pelvic cavity. At this
time, the procedure has generally replaced culdoscopy. Figure 16–12 depicts a typical gynecologic
laparoscopy with the instruments in place to manipulate and view the pelvic organs. For this test, the
abdomen is insufflated with carbon dioxide. Despite
the fact that carbon dioxide can lead to more
discomfort than nitrous oxide and can cause hyper-

Figure 16–11. Gastrointestinal laparoscopy.

390

SECTION II—Diagnostic

Tests and Procedures

Figure 16–12. Gynecologic laparoscopy.

carbia and cardiac dysrhythmias, it is used whenever
general anesthesia and electrocoagulation are used
during the procedure because it is less likely to
support combustion.53
Another endoscopic procedure is the fetoscopy. It
allows for direct visualization of the fetus through a
fiber-optic scope with a light source and telescopic
lens inserted through the abdomen and into the
uterus. Ultrasonography is performed to identify the
area of the fetus to be viewed for insertion of the
fetoscope.54 The procedure takes place at about 18
weeks’ gestation at the time the vessels of the placental surface are of adequate size and areas of the fetus
are more easily identified.55 A signed informed
consent that specifically identifies which procedure
is to be performed is required.
Reference Values
Gastrointestinal Laparoscopy. Normal appearance of the liver, spleen, gallbladder, pancreas, and
other abdominal contents
Gynecologic Laparoscopy. Normal appearance of
the ovaries, fallopian tubes, uterus, and other
pelvic contents
Fetoscopy. Absence of fetal distress, congenital
malformation, or blood disorders
INTERFERING FACTORS

Inability to cooperate during the procedure, if it is
performed with local anesthesia
Obesity

Abdominal or pelvic adhesions
INDICATIONS FOR LAPAROSCOPY

Gastrointestinal Laparoscopy
Evaluation of abdominal pain of unknown etiology when other diagnostic studies are inconclusive
Evaluation for possible appendicitis
Evaluation of an abdominal mass of unknown
etiology
Suspected benign or malignant liver disease to
determine the nature of the problem by obtaining
a biopsy of tissue rather than by performing a
“blind” percutaneous liver biopsy in which malignant cells can be missed56
Diagnosis of cirrhosis of the liver
Determination of stage of malignant disorders
such as Hodgkin’s disease, lymphomas, and
hepatic carcinoma57
“Second look” for possible metastases after
surgery for cancer of the colon58
Evaluation of jaundice of unknown etiology to
determine the cause, such as liver disease; gallstones; malignancies involving the gallbladder,
bile ducts, or liver
Assistance in performing surgical cholecystectomy via the laparoscopic procedure
Diagnosis of disorders involving the pancreas,
such as acute and chronic pancreatitis or cancer of
the pancreas
Evaluation of problems involving the spleen,
especially splenomegaly caused by portal hypertension
Evaluation of problems involving the peritoneum,

CHAPTER 16—Endoscopic

such as ascites caused by portal hypertension;
tuberculosis; and metastatic cancer from primary
sites such as the ovaries, colon, pancreas, lung, and
breast59
In emergency situations, evaluation of abdominal
trauma such as blunt injury or stab wounds to
determine the extent of intra-abdominal bleeding
and the need for exploratory surgery, especially in
clients who are poor surgical risks60
Gynecologic Laparoscopy
Evaluation of amenorrhea and infertility to determine the possible cause
“Second look” after therapy for fertilization
Evaluation of fallopian tubes and anatomic
defects to determine the cause of infertility
Tubal sterilization61
Suspected ectopic pregnancy to determine the
need for surgery
Determination of the cause of pelvic pain or
masses or unknown etiology
Evaluation of known or suspected endometriosis
Treatment of endometriosis through electrocautery or laser vaporization
Diagnosis of pelvic inflammatory disease
Diagnosis of uterine fibroids, ovarian cysts, and
uterine malformation with aspiration of ovarian
cysts during the procedure
Assistance in performing surgical vaginal
hysterectomy via the laparoscopic procedure
Diagnosis of pelvic malignancies by obtaining
tissue biopsy for laboratory analysis during the
procedure
Evaluation for possible removal of adhesions or
foreign bodies such as intrauterine devices62
Fetoscopy
Diagnosis of severe fetal malformations such as
neural tube defect
Obtaining of fetal blood samples for examination
to detect congenital blood disorders such as
hemophilia or sickle cell anemia
Obtaining of fetal skin biopsy for examination to
determine the presence of skin disorders63
CONTRAINDICATIONS

Peritoneal adhesions that could prevent adequate
visualization or lead to bleeding or perforation of
the bowel64
History of peritonitis, because dense adhesions
could have resulted
Presence of peritonitis, palpable abdominal mass,
or large abdominal hernia
History of multiple abdominal operations,
because dense adhesions could have resulted
Acute infection involving the abdominal wall,

Studies

391

because organisms can be introduced into the
normally sterile peritoneal cavity
Intestinal obstructions, because dilated loops of
bowel can be inadvertently perforated
Severe ascites or extreme obesity, because the
procedure would be technically very difficult to
perform
Coagulation disorders, especially those that
cannot be adequately corrected, because the
control of abdominal wall bleeding can be
affected65
Unstable cardiopulmonary status or chronic
tuberculosis
Gestation of less than 18 weeks for fetoscopy
because the fetal parts cannot be identified until
this time, and the blood vessels in the placental
surface are not of the appropriate size to secure
blood samples66
Nursing Alert

Preparation to initiate laparotomy care is
required for uncontrolled bleeding or other
complications of the procedure that can lead
to surgical intervention.
Premature delivery or change in the status of
the fetus requires monitoring of fetal heart
rate (FHR) and fetal and uterine activity
during and after the procedure.

NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The location for the procedure
That a physician will explain the benefits, risks,
and precautions taken during the procedure to
prevent complications
That the procedure requires 30 to 60 minutes to
complete or 1 to 2 hours for fetoscopy
That foods and fluids are withheld for 8 hours
before the procedure regardless of the anesthesia
used
That a local anesthesia is usually used for
gastrointestinal laparoscopy and fetoscopy; a
general anesthesia is usually used for gynecologic
laparoscopy
That, if the laparoscopy is to be performed under
general anesthesia, preparation includes the usual
preoperative activities and instruction
That a sedative is administered before the procedure to promote relaxation and that, if fetoscopy
is to be performed, a medication is administered
to quiet the fetus and facilitate the procedure

392

SECTION II—Diagnostic

Tests and Procedures

That a special microscope-like instrument is
inserted into the abdomen through a small incision near the umbilicus; for fetoscopy, a smaller
instrument is inserted through the abdominal
wall and into the uterine cavity
That vital signs and fetal well-being are monitored during and after the procedure
That the incision is closed with sutures, slips, or
Steri-Strips and a small dressing is applied
Prepare for the procedure:
Obtain a history of gestational age if fetoscopy is
to be performed; medical disorders that could
prevent performing gynecologic laparoscopy or
fetoscopy; blood clotting ability with results of
CBC, platelet count, PT, and PTT; and typing,
cross-matching, and Rh factor if fetoscopy is to be
performed.
Provide a hospital gown.
Remove full or partial dentures and glasses or
contact lenses, and perform other preoperative
activities if general anesthesia is to be administered.
Initiate IV line or venous access device such as
heparin lock, or both, as ordered.
Have the client void. Insert an indwelling catheter
to maintain an empty bladder if gynecologic
laparoscopy is to be performed.
Shave abdomen if unusually heavy hair growth is
present.
Take and record vital signs and FHR as applicable
for later comparison readings.
Administer premedications SC or IM as ordered.
(Premedications can include antibiotic therapy
as a preventive measure, an analgesic such as
meperidine [Demerol] to reduce discomfort, a
sedative such as diazepam [Valium] to promote
relaxation, and an anticholinergic such as
atropine sulfate to reduce secretions.)
THE PROCEDURE

Gastrointestinal Laparoscopy. The client is positioned on the laparoscopy table and shoulder braces,
footrest, and safety belts are applied to prevent
falling or slipping as the table is tilted into various
positions. If not already initiated, an IV infusion is
begun and maintained at a “keep-vein-open” rate to
avoid overdistention of the bladder. Additional sedation can be administered via the IV line at this time.
The abdomen is cleansed with antiseptic solution
and sterile drapes are placed in position around the
incision site.
The site for insertion of the scope is identified and
infiltrated with local anesthetic. After the skin is
anesthetized, deeper layers of the abdominal wall are
injected with anesthetic. Inform the client that this

causes a stinging sensation. A small skin incision
about 10 mm in length is made, and a Veress needle
is inserted into the incision. The Veress (pneumoperitoneum) needle is a special needle with a
blunt inner needle that protrudes beyond a pointed,
sharp outer needle with a beveled edge. During the
insertion, the blunt needle is pushed back, allowing
the sharp needle to penetrate the layers of the
abdominal wall. After insertion, the blunt needle is
pushed beyond the sharp one to prevent damage to
the abdominal viscera.67 Before the insertion of the
Veress needle, the client is requested to tense the
abdomen and perform Valsalva’s maneuver, so that
the abdominal wall is elevated, allowing for maximal
distance between the visceral and parietal peritoneums.68
Nitrous oxide or other gas is injected into the
abdomen to create pneumoperitoneum. This condition separates the abdominal wall from the abdominal viscera to improve visualization and protect the
organs from possible injury and damage from the
laparoscope. An average of 3 L of gas is necessary to
allow for the space required to insert the scope without damage to the abdominal organs. If the client
has ascites, it may be necessary to remove 1 or 2 L of
fluid before instilling the gas.
The Veress needle is then removed and a trocar is
inserted through the incision. The trocar provides a
sleeve through which the scope is inserted (see Fig.
16–11). In addition, some physicians insert a second
trocar in the upper right portion of the abdomen
through which accessory instruments such as
needles can be inserted to perform liver biopsies.
This type of procedure requires an additional injection of local anesthetic.69 The abdomen is then thoroughly explored via the laparoscope, with the table
tilted slightly in various positions such as head up,
head down, and lateral. Tissue samples for biopsy
can be obtained from the liver, peritoneum, and
spleen during the procedure.
When the examination is completed, the laparoscope is removed. Most of the air that was instilled
into the abdomen is then expelled through a valve
on the trocar. The trocar is removed and the skin
incision closed with sutures, clips, or Steri-Strips. A
small dressing or Band-Aid is applied to the incision
site and to the accessory trocar site if used. In an
emergency situation the procedure can be
performed in 15 to 30 minutes, because the primary
purpose is to assess for intra-abdominal bleeding.70
Gynecologic Laparoscopy. The client is placed on
the laparoscopy table and general anesthesia is
administered. The client is then placed in a modified
lithotomy position with the head tilted downward.

CHAPTER 16—Endoscopic

The external genitalia are cleansed with an antiseptic
solution and draped. The client can be catheterized
at this time if an indwelling catheter is not in place.
A bimanual pelvic examination can be performed
before a uterine manipulator is inserted through the
vagina and cervix and then into the uterus to permit
organs such as the ovaries, fallopian tubes, and
uterus to be moved for better visualization71 (see
Fig. 16–12).
The abdomen is cleansed with antiseptic solution
and sterile drapes positioned around the incision
site. A small incision is made and a pneumoperitoneum created, using a technique similar to the one
used for the gastrointestinal procedure except that
the gas used for insufflation is usually carbon dioxide. The pneumoperitoneum needle is removed, and
the trocar and laparoscope are inserted through the
incision. The pelvic organs are visualized and examined, tissue samples collected, and therapeutic
procedures performed such as tubal sterilization.
The scope is withdrawn, carbon dioxide is evacuated
via the trocar, and then the trocar is removed. The
skin incision is closed as outlined previously, the
uterine manipulator is removed, and a perineal pad
is applied after the perineum is cleansed.
Fetoscopy. The client is given meperidine
(Demerol) by injection to quiet the fetus and facilitate the procedure. The client is placed in the supine
position on the examining table and draped with the
abdomen exposed. Ultrasound is performed to
locate the fetus and placenta and to identify the incision site. It also ensures that the fetus and placenta
are normal and will not be affected by the study. The
site is cleansed with antiseptic solution and a local
anesthetic injected. The fetoscope, a very small telescopic instrument, is then inserted through the incision and passed into the uterine cavity near the
placental site. Visualization of the fetus is performed
to view abnormalities present at this stage of fetal
development. Accessory instruments are inserted to
obtain blood samples from the vessels of the umbilical cord or skin samples from the fetus.
After the examination and collection of specimens, the scope is withdrawn. The skin incision is
closed as outlined for the other laparoscopies.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after laparoscopy performed
under local or general anesthesia include placing the
client on a stretcher and transporting to a recovery
area.
Ensure that cardiac monitoring and cardiopulmonary resuscitation equipment are available
after, as well as during, the procedure.

Studies

393

Monitor vital signs, cardiac rhythm, respiratory
status, and comfort level, and compare them with
baseline readings.
If a liver biopsy was performed, place the client on
bed rest for 24 hours.
If fetoscopy has been performed, assess FHR,
and monitor the mother and fetus for changes
in blood pressure, pulse, uterine activity, fetal
activity, vaginal bleeding, and loss of amniotic
fluids.72
Resume food, fluid, and activities when the client
has stabilized and no immediate signs of complications are present (usually within 2 hours after
the procedure).
Administer a mild analgesic and cold applications
for shoulder pain caused by the elevation of the
diaphragm from the air injected into the
abdomen.
Administer Rho(D) immune globulin (RhoGAM)
to Rh-negative mothers unless fetal blood is
found to be Rh-negative.
Caution the client to report persistent shoulder or
abdominal pain, blood in the urine or feces, vaginal bleeding, leakage of amniotic fluid, fever,
painful contractions, or changes at the incision
site, depending on the procedure performed.
Inform the client who has had a fetoscopy to avoid
strenuous activity for 1 to 2 weeks and to keep her
appointment to have ultrasonography the next
day to ensure that the fetus and placenta are
normal and unaffected by the procedure.
Reaction to anesthetic agent or medications:
Note and report tachycardia or bradycardia,
hyperpnea, hypertension, or hypotension.
Administer ordered antihistamine. Initiate IV line
and resuscitation procedure if needed.
Bleeding (abdominal wall, organ, or blood vessel
laceration): Note and report abdominal pain,
blood in urine or feces, guarding or tenderness,
decreased bowel sounds, or decreased blood pressure and increased pulse. Administer ordered
medications and IV fluid to replace fluid loss.
Prepare the client for surgical repair.
Perforation of the gastrointestinal tract or
damage to organs: Note and report signs and
symptoms outlined for laceration or fever if peritonitis is present. Administer ordered antibiotic
therapy and other medications. Prepare for surgical repair.
Cardiac or pulmonary abnormalities: Note and
report cardiac dysrhythmias, chest pain, tachycardia, signs and symptoms of air embolism,
subcutaneous emphysema such as respiratory
difficulty, change in breathing pattern and breath
sounds, tachypnea, or hypercarbia if carbon

394

SECTION II—Diagnostic

Tests and Procedures

dioxide is used to create pneumoperitoneum.73
Initiate oxygen. Administer ordered medications.
Monitor ECG and respiratory status.
Premature membrane rupture or fluid leakage:
Note and report rupture and amount of fluid loss,
FHR, and fetal and uterine activity. Provide pad
and maintain bed rest. Provide support to allay
anxiety.
Premature birth, abortion, intrauterine death:
Note and report fetal and uterine activity and
spontaneous abortion and condition of fetus.
Provide support and monitor postdelivery condition of mother for hemorrhage and infection.

ARTHROSCOPY
Arthroscopy is the direct visualization of the internal
structures of a joint by means of a rigid fiber-optic
arthroscope. The procedure can be preceded by an
arthrography that has indicated some abnormality
to be investigated, but this is not always the case. The
knee is the joint most commonly examined (Fig.
16–13). Other joints that can be evaluated by
arthroscopy include the shoulder, elbow, hip, ankle,
and wrist.74 This procedure is becoming the study of
choice in the diagnosis of injuries and disorders of
the knee, especially when the problem is not readily
identified by plain x-rays. Moreover, arthroscopy
allows 30 percent more visibility in the knee than
does an exploratory arthrotomy.75 Arthroscopy can
be performed for both diagnostic and therapeutic
purposes.

Reference Values
Normal appearance of synovial membranes,
cartilage, ligaments, and tendons; no degenerative changes, inflammation, injury, or foreign
loose bodies.
INTERFERING FACTORS

Inability to cooperate or maintain a position of
the joint to be examined if the procedure is to be
performed under local anesthetic
Arthrography performed within 7 to 10 days of
the procedure if contrast medium remains in the
joint
INDICATIONS FOR ARTHROSCOPY

Suspected injury to the joint, such as torn meniscus in the knee or ruptured or torn ligaments,
especially when other studies such as plain x-rays
or arthrograms (radiologic visualization of a joint
after dye is injected) are inconclusive76
Suspected disorder involving the synovial
membrane, such as in synovitis
Diagnosis of acute and chronic joint disorders,
such as arthritis
Diagnosis of inflammatory disorders of the bone
or cartilage, such as osteochondritis dissecans
Evaluation of disorders involving the patella, such
as chondromalacia
Aspiration of fluid or obtaining of tissue biopsy
for laboratory analysis

Figure 16–13. Arthroscopy of the knee.

CHAPTER 16—Endoscopic

Monitoring of the response to therapy for various
joint disorders77
Correction of disorders involving the knee, such
as torn cartilage (closed meniscectomy) and
removal of degenerative patellar cartilage (patellar
shaving)78
Removal of loose bodies consisting of bone and
cartilage that result from inflammation, degeneration, or injury79
CONTRAINDICATIONS

Severe ankylosis of the joint (stiffness usually
caused by adhesions), because it can impair
adequate manipulation of the knee (flexion of 40
degrees) and scope for complete visualization of
the area
Superficial infection at or near the arthroscope
insertion site, because infectious organisms can be
introduced into the joint and possibly the bloodstream by instrumentation
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for laparoscopy (see preceding section).
Inform the client of the site of scope insertion and
the fact that some discomfort is experienced when
the local anesthetic is injected, that a tourniquet
may be applied to the extremity, and that activities
and weight bearing may be restricted, depending
on the procedure.
Teach crutch-walking, and provide the client with
an opportunity to practice.
Inform the client to report fever, swelling of the
joint, or redness or swelling of the incision site to
the physician.
Obtain a history of known or suspected musculoskeletal disorders, treatment regimen, and tests
and procedures associated with this system.
Perform an orthopedic prep that includes scrubbing the site, applying a sterile wrap, and shaving
the area 6 inches above and below the arthroscopy
site as ordered.
THE PROCEDURE

The procedure varies with the physician and the
joint being examined or treated. Anesthesia can be
local or general, depending on the extent of the
procedure to be performed, with general anesthesia
administered for surgical procedures. After the client
is positioned on the table with the site exposed, the
skin is prepared with an antiseptic solution and
draped. Sterile technique is used throughout the
procedure.
For arthroscopies of the knee (the most common
site examined), the entire leg can be wrapped with

Studies

395

an elastic bandage and elevated to drain blood from
the leg.80 Other measures to control bleeding
include the application of a pneumatic tourniquet
and the addition of epinephrine to the local anesthetic or to the saline solution used to irrigate and
distend the joint during the procedure.
After the desired anesthesia has been achieved, a
small incision is made and a sharp trocar inserted.
Fluid can be aspirated from the joint at this time.
The trocar is removed and the proper-sized scope
inserted, usually with the knee in a flexed position
(see Fig. 16–13). The diameter of the scope depends
on the joint to be examined and the purpose of the
procedure. Saline is injected via the arthroscope to
distend the joint. The arthroscope is also maneuvered within the joint and the extremity manipulated by the examiner as necessary for maximal
visualization of all structures. Culture, biopsy, surgical repair, and removal of loose bodies can take place
as indicated. The joint is irrigated and medication
instilled before the scope is withdrawn and after the
irrigating fluid has been removed by placing pressure on the knee.
For certain procedures such as closed meniscectomy and patellar shaving, the irrigating catheter can
be inserted via a second puncture wound, and a
third puncture site can be used to introduce surgical
instruments into the area.
The wounds are closed at the conclusion of the
procedure with a single suture or with Steri-Strips. A
sterile dressing is applied and the area wrapped with
an elastic bandage. Depending on the extent of the
procedure, the joint can be immobilized with
padding, plaster splints, or commercially made
immobilizers.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
placing the client on a stretcher and transporting to
a recovery area for additional monitoring of vital
signs, peripheral pulses, and comfort level.
Administer a mild analgesic for pain and apply an
ice pack to the site to reduce swelling.
Provide the client with assistive devices such as
crutches or arm sling if needed, and remind the
client of the correct use or application.
Review and instruct the client in any activity and
weight-bearing restrictions, as well as in exercising and positioning of the joint.
Instruct the client in the care of immobilizing
devices that have been applied to the joint and in
the care of the incision area.
Remind the client to report fever, swelling of the
joint, pain at the site, changes in color or sensation
in the extremity, or changes in the incision area.

396

SECTION II—Diagnostic

Tests and Procedures

Reaction to medications or anesthetic: Note and
report changes in vital signs (hypotension, bradycardia) or respiratory changes (cyanosis, changes
in breathing pattern and breath sounds).
Administer ordered antihistamine. Initiate oxygen
or resuscitation procedure, or both, as needed.
Infection: Note and report fever, swelling of the
joint, redness or swelling of the incision site, or
pain at the site or in the joint. Administer ordered
antibiotic and analgesic therapy. Apply ordered
heat treatments.
Thrombophlebitis: Note and report pain or
redness and warmth of the calf area. Elevate leg,
refrain from massaging the area, apply ordered
moist heat, and administer ordered analgesic and
anticoagulant.
Hemarthrosis or joint injury: Note and report
joint pain or swelling. Immobilize limb.
Administer ordered medication for pain.81
Neurovascular damage: Note and report changes
in color, peripheral pulse, capillary refill, sensation, and temperature of the extremity. Perform
neurological and circulatory checks. Monitor
dressing tightness. Instruct in precautions to take
to prevent trauma to the extremity.
REFERENCES
1. Thomas, CL (ed): Taber’s Cyclopedic Medical Dictionary, ed 19. FA
Davis, Philadelphia, 2000.
2. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 641.
3. Ibid, p 641.
4. Smith, MJ, et al: Child and Family: Concepts of Nursing Practice.
McGraw-Hill, New York, 1982, p 635.
5. Porth, CM: Pathophysiology: Concepts of Altered Health States, ed
5. JB Lippincott, Philadelphia,1998, p 478.
6. Haponik, EF, et al: Bronchoscopy and related procedures. In
Fishman, AP: Pulmonary Diseases and Disorders, ed 2, vol 1.
McGraw-Hill, New York, 1988, pp 437–440.
7. Ibid, p 437.
8. Ibid, p 440.
9. Pagana, KD, and Pagana, TJ: Mosby’s Diagnostic and Laboratory
Test Reference. Mosby–Year Book, St Louis, 1992, p 570.
10. Haponik, op cit, p 461.
11. Pagana and Pagana, op cit, p 130.
12. Haponik, op cit, p 442.
13. Ibid, p 445.
14. Ibid, p 441.
15. Nurse’s Reference Library, op cit, p 646.
16. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed 4.
JB Lippincott, Philadelphia, 1992, p 728.
17. Nurse’s Reference Library, op cit, p 646.
18. Fischbach, op cit, p 278.
19. Nurse’s Reference Library, op cit, p 646.
20. Ibid, p 733.
21. Pagana and Pagana, op cit, p 321.
22. Carey, WD: Indications, contraindications, and complications of
upper gastrointestinal endoscopy. In Sivak, MV: Gastroenterologic
Endoscopy. WB Saunders, Philadelphia, 1987, p 296.
23. Sivak, MV: Technique of upper gastrointestinal endoscopy. In
Sivak, MV: Gastroenterologic Endoscopy. WB Saunders,
Philadelphia, 1987, pp 276–277.
24. Carey, op cit, p 297.
25. Sivak, op cit, p 274.

26. Ibid, p 288.
27. Pagana and Pagana, op cit, p 305.
28. Ferguson, DR, and Sivak, MV: Indications, contraindications, and
complications of ERCP. In Sivak, MV: Gastroenterologic
Endoscopy. WB Saunders, Philadelphia, 1987, p 586.
29. Ibid, p 589.
30. Ibid, pp 588–589.
31. Vennes, JA: Techniques of ERCP. In Sivak, MV: Gastroenterologic
Endoscopy. WB Saunders, Philadelphia, 1987, p 565.
32. Fischbach, op cit, p 738.
33. Ferguson and Sivak, op cit, p 593.
34. Ibid, p 594.
35. Nurse’s Reference Library, op cit, p 836.
36. Fischbach, op cit, p 746.
37. Manier, JW: Flexible sigmoidoscopy. In Sivak, MV:
Gastroenterologic Endoscopy. WB Saunders, Philadelphia, 1987, p
983.
38. Ibid, p 983.
39. Kee, JL: Laboratory and Diagnostic Tests with Nursing
Implications, ed 3. Appleton & Lange, Norwalk, Conn, 1997, p 364.
40. Sakai, Y: Technique of colonoscopy. In Sivak, MV:
Gastroenterologic Endoscopy. WB Saunders, Philadelphia, 1987, p
842.
41. Ibid, p 863.
42. Rankin, GB: Indications, contraindications, and complications of
colonoscopy. In Sivak, MV: Gastroenterologic Endoscopy. WB
Saunders, Philadelphia, 1987, pp 868–873.
43. Sakai, op cit, pp 850–865.
44. Fischbach, op cit, p 745.
45. Ibid, p 742.
46. Pagana and Pagana, op cit, p 254.
47. Ibid, p 254.
48. Ibid, p 41.
49. Ibid, p 345.
50. Ibid, p 346.
51. Nord, JH: Technique of laparoscopy. In Sivak, MV:
Gastroenterologic Endoscopy. WB Saunders, Philadelphia, 1987, p
996.
52. Ibid, p 1008.
53. Ibid, p 996.
54. Fischbach, op cit, p 929.
55. Pagana and Pagana, op cit, p 347.
56. Lightdale, CJ: Indications, contraindications, and complications of
laparoscopy. In Sivak, MV: Gastroenterologic Endoscopy. WB
Saunders, Philadelphia, 1987, p 1032.
57. Ibid, p 1030.
58. Ibid, p 1034.
59. Ibid, p 1038.
60. Berci, G: Emergency laparoscopy. In Sivak, MV: Gastroenterologic
Endoscopy. WB Saunders, Philadelphia, 1987, p 1120.
61. Yuzpe, AA: Gynecologic laparoscopy for the gastroenterologist. In
Sivak, MV: Gastroenterologic Endoscopy. WB Saunders,
Philadelphia, 1987, p 1125.
62. Ibid, p 1125.
63. Pagana and Pagana, op cit, p 347.
64. Lightdale, op cit, p 1038.
65. Ibid, p 1039.
66. Pagana and Pagana, op cit, p 347.
67. Nord, op cit, pp 994–995.
68. Ibid, p 1007.
69. Ibid, pp 1016–1018.
70. Berci, op cit, p 1122.
71. Pagana and Pagana, op cit, p 456.
72. Ibid, p 348.
73. Lightdale, op cit, pp 1038–1040.
74. Fischbach, op cit, p 761.
75. Farrell, J: Illustrated Guide to Orthopedic Nursing, ed 3. JB
Lippincott, Philadelphia, 1986, p 229.
76. Nurse’s Reference Library, op cit, p 679.
77. Pagana and Pagana, op cit, p 75.
78. Farrell, op cit, p 230.
79. Ibid, p 233.
80. Nurse’s Reference Library, op cit, p 681.
81. Pagana and Pagana, op cit, p 75.

CHAPTER

Radiologic Studies
PROCEDURES COVERED
Skull Films, 400
Orbital Films, 401
Paranasal Sinus Films, 401
Chest Films, 402
Abdominal Films, 404
Obstruction Series, 405
Pelvimetry, 405
Spinal Films, 406
Extremity Films, 407
Dual Energy X-Ray Absorptiometry (Dual
X-Ray Absorptiometry), 408
Cardiac Films, 409
Chest Tomography, 410
Paranasal Sinus Tomography, 411
Mammography, 411
Barium Swallow, 413
Upper Gastrointestinal Series, 414
Barium Enema, 416

Oral Cholecystography, 417
Intravenous Cholangiography, 419
T-Tube Cholangiography, 420
Operative Cholangiography, 422
Percutaneous Transhepatic
Cholangiography, 422
Antegrade Pyelography, 424
Retrograde Urethrography, 426
Retrograde Cystography, 427
Retrograde Ureteropyelography, 428
Intravenous Pyelogram, 429
Voiding Cystourethrography, 430
Sialography, 430
Arthrography, 431
Bronchography, 432
Hysterosalpingography, 433
Myelography, 434

INTRODUCTION

Radiographs (also called x-rays and roentgenograms) are used to evaluate the bones and soft tissues of the body. The x-rays are produced by applying an electron
beam to a vacuum tube containing tungsten. The resulting rays have a shorter wavelength than
that of visible light rays and are able to penetrate many substances that are opaque to visible
light.
In photographic film, x-rays cause silver to precipitate. This precipitation causes the film to
turn black when it is developed. Objects placed between the beam of x-rays and the photographic film absorb some of the x-rays and cause a shadow to be cast upon the film.1 The
amount of x-rays absorbed varies with the thickness and composition of the object. Metal, for
example, absorbs all of the x-rays and no silver is precipitated; when the film is developed, the
object appears solid white. In contrast, soft tissues absorb only part of the x-rays and cause a
grayish shadow to be cast on the film.2 The usefulness of diagnostic radiography is based on the
differences in the absorption of rays by various substances or objects.
Because x-rays precipitate silver in photographic film slowly, clients may potentially be
exposed to unduly long studies and excessive radiation. To avoid these problems, special film
cassettes are used. These cassettes contain a fluorescent screen that is activated by the x-rays and
emits light rays that augment the effects of x-rays on the photographic film.3
397

398

SECTION II—Diagnostic

Tests and Procedures

For many body parts, such as bones and air-filled soft structures, differences in composition
and density produce natural contrasts that are sufficient for “plain” films of diagnostic quality.
Solid organs and hollow structures that do not normally contain air, however, require either
special filming techniques such as tomography or use of radiopaque contrast media such as
barium sulfate or iodinated dyes for accurate imaging.
Radiographic procedures can be either invasive or noninvasive, and client preparation varies
accordingly. In the case of noninvasive procedures such as plain-film x-rays, tomography, and
those using barium sulfate as a contrast medium, the client should be told what to expect, but
a signed consent form is not required. The only exception to this is mammography, which uses
xeroradiography to create its images. A signed consent form is required for invasive procedures
that use iodinated dyes administered intravenously (IV) or directly into an organ or area to be
examined. The procedures are usually performed in the radiology department or a special
room with x-ray equipment, but some can be performed at the bedside, in the physician’s
office, or at an imaging agency. Such studies can be performed by a qualified radiologist, urologist, or x-ray technician. All invasive radiologic procedures are performed under sterile conditions using standard precaution procedures.

TOMOGRAPHY
Tomography (laminography, planigraphy, stratigraphy) is an imaging technique in which a selected
body plane is isolated from the tissues on either side.
The x-ray source and the film are moved in opposite
directions, resulting in a two-dimensional slice a few
millimeters thick that is imaged with a clarity superior to that of plain films. Tomography is especially
valuable in visualizing air-filled structures such as
the lungs, paranasal sinuses, and kidneys. Used
alone, tomography provides two-dimensional grayscale images; when combined with computers in
computed scans or CTs, tomography produces
three-dimensional images. A disadvantage of
tomography is the high level of radiation exposure
to the client.

FLUOROSCOPY
Fluoroscopy is an imaging technique in which x-rays
are passed through the client to a fluorescent viewing screen coated with calcium tungstate. The viewer
is able to observe movement in the area being filmed
while the study is in progress, making fluoroscopy
particularly useful in evaluating movement of the
diaphragm, heart, and digestive system (esophagus,
stomach, small bowel, colon). It is also used in
catheter guidance for placement during angiography, needle insertion for biopsy or removal of fluid
from a body cavity, and nasogastric (NG) tube insertion for precise placement in the stomach or small
bowel. Fluoroscopy can be used with single films
(spot films) or with videotape if a record of move-

ment is desired. Fluoroscopy is also often used in
combination with other radiologic procedures and
techniques, such as plain films or cineradiography,
and it is frequently augmented by the addition of a
contrast medium such as barium sulfate.
The viewer faces the screen during fluoroscopy
and thus can be exposed to x-rays. For this reason,
the viewer must wear special lead-shielded glasses,
gloves, and aprons for protection. Fluoroscopy delivers much larger doses of radiation than conventional
x-rays. Newer fluoroscopy equipment, which has
image intensifiers that amplify the pictures electronically, allows the studies to be performed in lighted
rooms, thus exposing the client and fluoroscopist to
less radiation.4

CINERADIOGRAPHY
Cineradiography is a rapid-sequence filming technique similar to that used to make motion pictures.
When used with fluoroscopy, it creates a photographic record of the motion under study, such as
swallowing. The resulting film is comparable to
photographs taken with a 16- or 35-mm camera at
speeds of 30 to 200 frames per second. A recording
for later replay allows study in greater detail.

XERORADIOGRAPHY
Xeroradiography is an x-ray imaging technique
that uses a photoelectric process rather than the
photochemical process of conventional x-rays;
this process reduces the amount of radiation exposure to the client. The images are printed on paper in

CHAPTER 17—Radiologic

a manner similar to that of a typical office copier.5
Xeroradiography produces very distinct images with
excellent contrast. Because it is especially useful in
studying soft tissues for small-point abnormalities, it
is used primarily for x-ray studies of the breasts.

CONTRAST-MEDIATED STUDIES
Soft tissues produce poor images on x-ray, and
contrast media are added to enhance the viewing of
structural details. A contrast medium can be administered orally, rectally, IV, intrathecally, or by insufflation. When contrast media are injected to
visualize blood vessels and lymphatics, the studies
are referred to as angiography.
The most commonly used contrast media are
barium sulfate, organic iodides, and iodized oils.
These substances are radiopaque and block the
passage of x-rays. Gases such as oxygen, carbon
dioxide, helium, nitrogen, and air have been used to
render body spaces radiolucent because the spaces
partially block the passage of x-rays. Many of the
studies in which gases are used have now been
replaced by safer, noninvasive CT and other imaging
techniques.
In addition to the radiation hazards inherent in all
x-ray studies, contrast-mediated procedures pose
the additional risk of severe allergic reaction to the
iodinated contrast medium, including vomiting,
laryngospasm, anaphylactic shock, and cardiac
arrest (Table 17–1). Emergency equipment should
be at hand so that resuscitative measures can be
initiated immediately.
Barium sulfate is a chalky emulsion that is
flavored and aerated to the consistency of a milk
shake. Oral ingestion of this medium can lead to
nausea and vomiting as well as to prolonged retention of the barium within the intestinal tract, leading
to constipation and impaction. The color of the feces
will be white or much lighter than usual until the
barium is eliminated from the tract.

RADIATION EXPOSURE RISKS
All radiation studies carry risks of exposure to radiation. Radiation can have adverse effects on both
gonadal and somatic cells. The cells of the developing embryo are especially sensitive to radiation.
Children are at higher risk than adults, so this diagnostic method should be used only when absolutely
necessary. Possible adverse effects of radiation
include genetic mutations, cancer, and congenital
anomalies.6
X-ray studies should not be performed more
often than necessary for diagnosis. Clients should be

Studies

399

• Adverse Reactions to
Iodinated Contrast Media

TABLE 17–1

Manifestations of Reaction
Anxiety
Tachycardia
Diaphoresis
Sneezing, rhinorrhea
Urticaria, rash
Angioneurotic edema
Coughing
Dyspnea, wheezing
Hoarseness
Laryngeal stridor
Hypotension
Pulmonary edema
Shock state
Cardiopulmonary failure
Cardiopulmonary arrest
Medications to Counteract Reactions
Diphenhydramine (Benadryl): PO (orally), IM for
mild reactions
Epinephrine (adrenalin): IV for severe reactions
Aminophylline: IV for severe reactions
Hydrocortisone (Solu-Cortef): IV for severe
reactions

adequately prepared so that the need for repeat films
and studies is reduced. Newer x-ray equipment and
film should be used because they expose clients and
personnel to less radiation than older equipment.
Personnel and clients should be shielded from
unnecessary exposure by lead aprons and gloves.
Women who are pregnant should not be x-rayed,
and women of childbearing age should be assessed
for the date of the last menstrual period to reduce
the possibility of having radiographic studies
performed during pregnancy. If undiagnosed pregnancy is a risk or if a pregnancy is not confirmed, the
study is generally not performed unless it is an
extreme necessity.7

PLAIN FILMS
Plain films are radiologic studies that use external
beams and are performed without contrast media or

400

SECTION II—Diagnostic

Tests and Procedures

Figure 17–1. Cranial and facial bones; cervical spine.

augmentation with other techniques. They are used
for “routine” examinations of areas such as the skull,
chest, abdomen, pelvis, spine, extremities, and bony
structures in other parts of the body. Plain x-rays are
contraindicated in pregnant clients unless the benefits of performing the procedure far outweigh any
risks to the fetus.

SKULL FILMS

Suspected metastatic tumor involving the small
bones or brain tissue revealed by a shift of
intracranial contents
Suspected acromegaly revealed by an enlarged
mandible
Suspected tumor or inflammation involving the
paranasal sinuses
Suspected Paget’s disease revealed by a thickening
of the skull bones
Suspected vascular abnormalities such as chronic
subdural hematoma revealed by calcifications in
brain tissue
Suspected perinatal injury or congenital defect
involving the skull
Evaluation of thinning of bones, separation of
suture lines, widened fontanels, and an enlarged
cranium in the diagnosis of hydrocephalus in
infants
Evaluation of premature closing of the cranial
sutures in the diagnosis of craniostenosis in
infants
CONTRAINDICATIONS

Skull films involve radiographic examination of the
cranial vault and facial bones (Fig. 17–1). A variety
of abnormalities can be identified on skull films,
such as fractures, tumors, and changes in bone
structure or size. Several views are taken, depending
on the signs and symptoms and the suspected
pathology. In cases involving fractures of the cervical
vertebrae, positioning to obtain varied views is
limited.
Reference Values
Normal skull, facial, and jaw bones; normal
brain tissue; normal suture lines and fontanels
in infant
INTERFERING FACTORS

Improper positioning to achieve the desired views
Limitations in positioning from known or
suspected fractures of the cervical vertebrae
Metal objects such as dentures, hearing aids, and
eyeglasses within the x-ray field
INDICATIONS FOR SKULL FILMS

Known or suspected trauma to the face or
cranium to reveal a fracture
Suspected increased intracranial pressure revealed
by abnormal markings on the inside of the cranial
vault
Suspected pituitary tumor revealed by increased
size and erosion of the sella turcica

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
The location for the procedure and the fact that a
technician or radiologist will perform it
That the procedure takes about 15 minutes
That foods, fluids, and medications are not
restricted before the procedure
That no sedation or anesthetic is administered
before the procedure
That views may be taken with the client in various
positions on the x-ray table or in an x-ray chair
That the area to be examined will be immobilized
or the client will be asked to remain still during
the procedure
That the procedure should not cause discomfort,
except possibly from lying on the hard table
Prepare for the procedure:
Obtain a history of known underlying medical
conditions or trauma and (for women) date of
last menstrual period to determine the possibility
of pregnancy.
Ensure that all dental prostheses, jewelry,
eyeglasses, or other metal objects such as hair clips
are removed.
Provide a hospital gown, if needed.
Perform baseline neurological check and vital
signs for later comparison readings.

CHAPTER 17—Radiologic

THE PROCEDURE

The client is placed on the x-ray table or seated in a
chair. Various views of the skull are taken with the
client repositioned and the head stabilized with a
headband, sandbags, or foam pads for each change
of position. For lateral (left and right sides), posterior and anterior (back to front), and basilar (inferior to superior) views, the client is placed in the
prone position; for anterior-posterior (AP) (front to
back) and axial (crown to chin) views, the client is in
the supine position. Varying degrees of neck flexion
are used for the different views. The client is
requested to remain very still while the x-rays are
taken. The positions are maintained while the films
are developed and checked in case more filming is
needed.8
NURSING CARE AFTER THE PROCEDURE

Perform neurological checks and vital signs and
compare with baselines.
Complications and precautions: Note and report
suspected fracture or injury to the cervical spine
or neck pain. Consider this limitation when positioning the neck during the x-ray procedure.

ORBITAL FILMS
Orbital films involve examination of the bony orbits
of the eyes (see Fig. 17–1). The procedure is indicated to diagnose fracture, tumor, or foreign body in
the orbit or in the eye itself as well as craniofacial
anomalies. As with skull films, several views are
taken, depending on known or suspected pathology
or abnormal conditions.
Reference Values
Orbits of normal size; no fractures, bony abnormalities, or foreign bodies

INTERFERING FACTORS

Improper positioning of the client to obtain the
desired views
Metal objects such as eyeglasses, eye prosthesis,
dentures, or jewelry within the x-ray field
INDICATIONS FOR ORBITAL FILMS

Identification of fractures after known or
suspected trauma to the eyes or face
Suspected tumor involving the orbit, hypophysis,
retina, or optic nerve revealed by alterations in the
size of the orbit

Studies

401

Suspected foreign body in the eye or in the orbit
itself
Suspected Paget’s disease revealed by an increased
density of the bone
Suspected congenital microphthalmia or other
craniofacial anomalies revealed by alterations in
the size of the orbit
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
THE PROCEDURE

The client is placed on the x-ray table in a supine
position or seated in an x-ray chair. Different views
of the orbits are taken such as posterior-anterior
(PA), inferior-superior (basilar), and projections
through the optical canal.9 The client is repositioned
for each view, and headbands, sandbags, and foam
blocks are used to stabilize the head for each position during the procedure. The client is requested to
remain very still during the procedure and to wait
while the films are developed and checked before
leaving the department.10
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).

PARANASAL SINUS FILMS
Paranasal sinuses are air-filled cavities lined with
mucous membrane in the frontal, ethmoid, sphenoid, and maxillary bones (see Fig. 17–1). Films are
taken to diagnose and evaluate the sinuses for fracture, inflammation, cysts, tumors, and foreign
bodies.
Reference Values
Normal sinus bones and soft tissues; no fractures, tumors, or inflammation
INTERFERING FACTORS

Inability of client to remain still and maintain
position during filming
Improper positioning for the desired views

402

SECTION II—Diagnostic

Tests and Procedures

Metal objects such as eyeglasses, dental or eye
prostheses, or jewelry within the x-ray field
INDICATIONS FOR PARANASAL SINUS FILMS

Detection of fractures to the head or face after
trauma
Suspected acute or chronic sinusitis revealed by
inflammation of the mucous membranes
Suspected cyst, polyp, or tumor involving the
sinuses revealed by soft tissue changes, bony
abnormalities, or both
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Figure 17–2. Posterior-anterior view for chest radiograph.

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
THE PROCEDURE

The client is seated in a special x-ray chair. The head
is immobilized in a padded brace or vise to maintain
the desired position. The client is requested to
remain very still to prevent any blurring of the image
while films are taken at different angles. Several
views can be taken, and the client is requested to
remain in position until the films are developed and
checked.11 The brace is then removed and the client
is allowed to leave the department.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).

CHEST FILMS
Chest x-rays (CXR) are among the most frequently
performed radiologic studies and yield a great deal
of information about the pulmonary and cardiac
systems. The lung fields, the clavicle and ribs, the
cardiac border, the mediastinum, the diaphragm,
and the thoracic spine can all be studied using CXRs.
Although generally performed in the radiology
department, chest x-rays using portable equipment
can be taken at the client’s bedside in more acute or
critical situations. Although only a single view is
obtained, critical problems such as pneumonia,
atelectasis, pneumothorax, pulmonary edema, and
pleural effusion can be identified. In addition,
portable chest x-ray equipment is often used to evaluate the placement of various tubes, such as central
venous catheters.12

Figure 17–3. Left lateral view for chest radiograph.

Chest x-ray studies can include several views. In
the posterior-anterior (PA) view (Fig. 17–2), the xray beam passes through the client from back to
front. This is a preferred view because it results in
less magnification of the heart than does the anterior-posterior (AP) view.13 The farther away from
the x-ray film an object is situated, such as the heart
in the AP view, the more magnified and less distinct
will be its image.14 Note, however, that portable
chest x-rays are performed using the AP view. The
lateral view (Fig. 17–3) is performed with the client’s
left side placed against the film and the arms positioned to avoid interference with the chest view. The
rationale for this position is the same as for the PA

CHAPTER 17—Radiologic

view; that is, the heart lies toward the left side of the
chest and is less magnified in the left lateral view.15
Lateral views add information that cannot be
obtained through PA filming. Two areas seen more
clearly on lateral views are the anterior portion of
the lungs closest to the mediastinum and the vertebral column.16
Oblique chest films are made by angling the x-ray
beam between the PA and the lateral views.17
Oblique views are helpful in evaluating pulmonary
masses and infiltrates, especially those involving the
mediastinum. These views can be supplemented
with barium swallow studies, because barium in the
esophagus aids in identifying mediastinal abnormalities.18
Lateral decubitus chest films are made by directing the x-ray beam parallel to the floor with the
client in a side-lying, supine, or prone position.19,20
Lordotic chest films are taken with the client leaning backward against the x-ray film with the
abdomen protruding.21 This position allows better
visualization of the apices of the lungs, the area most
commonly involved in pulmonary tuberculosis.
Fluoroscopic studies of the chest can also be
performed to evaluate movement of the chest and
diaphragm during breathing and coughing. It
provides information about bronchiolar obstruction, loss of elasticity, or paralysis of the
diaphragm.22
Reference Values
Normal lung fields, cardiac size, mediastinal
structures, and thoracic spine; no masses, infiltrates, areas of collapse, pleural effusion, fractures of clavicles or ribs, or abnormal elevation
or flattening of the diaphragm

Studies

403

ders such as pneumonia, tuberculosis, or lung
abscess
Diagnosis of obstructive pulmonary lung diseases
such as atelectasis, emphysema, or chronic bronchitis
Diagnosis of interstitial lung diseases such as
sarcoidosis, silicosis, or asbestosis
Diagnosis of pneumothorax or fractures of the
ribs or clavicles resulting from known or
suspected chest trauma
Known or suspected cardiovascular disorders
such as congestive heart failure (CHF), pericarditis, or aortic aneurysm
Monitoring of pulmonary or cardiac disease to
evaluate the effectiveness of therapy
Suspected diaphragmatic hernia
Suspected neoplasm (benign or malignant)
involving the mediastinum, lungs, or chest wall
Suspected pleural effusion or other abnormalities
involving the pleurae or fluid accumulation in the
lungs, as in pulmonary edema
Diagnosis of cystic fibrosis in children
Diagnosis of bronchopulmonary dysplasia, air
leak syndrome, hyaline membrane disease, and
meconium aspiration syndrome in infants
Evaluation of the placement and positioning of
endotracheal tubes, tracheostomy tubes, central
venous catheters, Swan-Ganz catheters, chest
tubes, NG feeding tubes, pacemaker wires, and
intra-aortic balloon pumps23
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).

INTERFERING FACTORS

Improper positioning, especially for views such as
the oblique and lordotic films or for portable
chest x-rays
Inability of client to take and hold deep breaths
during the filming
Improper adjustment of the x-ray equipment to
accommodate obese and thin clients, causing
overexposure or underexposure and poor-quality
films
Metal objects such as closures on undergarments
or hospital gown within x-ray field
INDICATIONS FOR CHEST FILMS

Known or suspected pulmonary infectious disor-

THE PROCEDURE

For Routine Films. The client is positioned in front
of the x-ray machine and against the film holder.
The client can be seated if unable to stand. For the
PA view, the client stands or sits facing the film with
the hands on the hips, neck extended, and shoulders
forward and touching the film holder. The client is
requested to inspire deeply and hold the breath
while the x-ray is taken. For the lateral view, the
client is positioned with the side (usually the left)
against the film holder with the arms raised over the
head and away from the x-ray field. The client is
again requested to hold the breath while the x-ray is
taken.

404

SECTION II—Diagnostic

Tests and Procedures

For Oblique, Decubitus, or Lordotic Views. The
client is assisted to the proper position. If fluoroscopic examination is being performed to visualize
movement of the thoracic contents, especially the
diaphragm and lung expansion and contraction, the
client is asked to breathe and cough as the films are
taken. Tissues are supplied for client use if coughing
is required during the study.
For Portable Chest X-Rays. The client is moved
toward the head of the bed as far as possible. The
head of the bed is raised as high as possible (preferably a 90-degree angle) or to the limit of the client’s
tolerance. Any metal objects on the gown or other
objects (electrodes, tubing) that can interfere with
the visualization of the chest are removed. The client
is helped to lean forward while the film cassette is
placed between the back and the mattress. If the
client cannot maintain a position for filming, a staff
member may assist if he or she wears a lead apron.
The client is eased back onto the cassette and
checked for proper positioning. The client is
requested to hold the breath, if possible, while the xray is obtained.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).

ABDOMINAL FILMS
A plain film of the kidneys, ureters, and bladder
(KUB), also called a scout film or flat plate, consists
of a single AP view of the abdomen (Fig. 17–4). The
abdominal film is commonly taken to assist in the
diagnosis of urologic and gastrointestinal abnormalities.
Reference Values
Normal shape and size of kidneys, with the right
kidney positioned slightly lower than the left;
normal bladder, if visualized; no renal calculi,
abdominal masses, abnormal accumulation of
air or fluid, or foreign objects within the
gastrointestinal tract

Figure 17–4. Supine position for abdominal radiograph.

INDICATIONS FOR ABDOMINAL FILMS

Diagnosis of intestinal obstruction and acute
abdominal pain of unknown etiology
Evaluation of palpable abdominal mass
Determination of size, shape, and position of
kidneys to aid in the diagnosis of congenital
anomalies and diseases such as absence of kidney
or horseshoe kidney, hypoplasia, polycystic
kidney disease, hydronephrosis, or atrophic
kidney
Determination of the size, shape, and position of
liver and spleen in liver cirrhosis, splenomegaly,
and tumors
Suspected abnormal air, fluid, or objects in the
abdomen
Evaluation of size, shape, and location of renal
calculi, revealed by visualization of opaque bodies
Differentiation between the cause of urologic
symptoms and gastrointestinal symptoms
Initial component of a contrast-mediated study of
the renal/urinary and gastrointestinal tract25
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
THE PROCEDURE

INTERFERING FACTORS

Feces, barium or other radiopaque substances,
gas, or ascites
Extreme obesity, uterine and ovarian tumors or
lesions24
Metal objects such as belts or girdles within the xray field

The client is placed on the x-ray table in the supine
position with the arms extended over the head. A
protective shield is placed over the testicular area of
male clients. Usually a single AP film of the
abdomen is taken, although a film with the client in
a sitting or standing position may be performed,
depending on the reason for the study.26 During the

CHAPTER 17—Radiologic

filming, the client is requested to take a deep breath
and hold it or exhale and not breathe. Visualization
of the bladder depends on its density and whether it
contains urine.27
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Monitor bowel sounds in clients who experience
abdominal pain.

OBSTRUCTION SERIES
For an obstruction series, a plain film of the
abdomen is followed by abdominal films in varying
positions. An obstruction series is performed to
reveal bowel obstruction as well as a variety of other
abdominal disorders, such as paralytic ileus. In
mechanical bowel obstruction, the small bowel and
colon become distended with air. This distention is
proximal to the obstruction, because air tends to be
cleared from the portion of the bowel distal to the
obstruction because of peristalsis. In paralytic ileus
both the small and large bowels are distended with
air because peristalsis is decreased. Free air can be
detected in the abdomen if the bowel ruptures.28
Reference Values
Normal small and large intestines; no abnormal
distention, mechanical bowel obstruction, paralytic ileus, or perforation
INTERFERING FACTORS

Feces, barium or other radiopaque substances,
gas, or ascites
Extreme obesity
Metal objects such as belts and girdles within the
x-ray field
INDICATIONS FOR OBSTRUCTION SERIES

Evaluation of acute abdominal pain of unknown
etiology such as appendicitis or abdominal
abscess
Suspected bowel perforation revealed by free air
under the diaphragm
Suspected bowel obstruction revealed by air and
fluid within the intestine that cause bowel distention proximal to the obstruction
Suspected paralytic ileus revealed by small-bowel
and colon distention with air as peristalsis
decreases
Suspected renal calculi revealed by calcification in
the kidney or a ureter

Studies

405

Monitoring of the course of renal or gastrointestinal disease
Suspected abdominal aortic aneurysm revealed by
calcification, especially in older clients29
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
THE PROCEDURE

The client is placed in a standing position. If the
client is unable to stand, he or she is helped into a
side-lying position on the x-ray table, and a left
lateral decubitus film is taken. A second film can be
taken with the client in the supine position with the
arms extended upward over the head for an AP view
of the abdomen. A third film can be taken for a
cross-table lateral view of the abdomen if an aortic
disorder is suspected.30 A single chest x-ray can also
be included in the series. Either a PA or an AP view
can be taken, depending on the client’s ability to
stand for the x-ray. If the client is unable to be transported to the radiology department, the study can be
performed at the bedside with a portable unit.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Monitor bowel sounds and assist with positioning
for comfort if the client is experiencing pain.
Reapply dressings as needed.

PELVIMETRY
Pelvimetry involves x-ray of the pelvis of a pregnant
woman at or near term. It is performed to determine
whether the pelvis is adequate in size relative to the
fetal head. The study is rarely used, but it is helpful
in determining whether a vaginal birth will be possible.31 Because this study does not take place until the
client is at or near term or during labor, the risk to
the fetus is minimal. However, the procedure should
not be performed unless absolutely necessary.
Reference Values
Normal pelvic diameters with size adequate in
relation to the fetal head

406

SECTION II—Diagnostic

Tests and Procedures

INTERFERING FACTORS

Excessive fetal activity
Metal objects within the x-ray field
INDICATIONS FOR PELVIMETRY

Maternal history of problems involving pelvic
bones or birthing process
Abnormal pelvic measurements
Suspected abnormal fetal presentation32
Failure of the fetal head to engage during the
labor phase
Possible administration of oxytocin (Pitocin) to
induce labor in the absence of labor progression
Confirmation of the need for a cesarean birth
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Obtain baseline fetal heart rate (FHR) for postprocedure comparison, if indicated.
Assess trimester of pregnancy, because study is
performed only at term or during labor phase.
THE PROCEDURE

The client is helped to a standing position and a
lateral view is taken to assess the lowest level of the
head in the birth canal. A second film can be taken
with the client in the supine position, supine position with knees flexed (semirecumbent), or sidelying position.33 When the client is in the supine
position and an anterior view is to be obtained, a
metal ruler (pelvimeter) can be placed at the level of
the ischial tuberosities, or it can be placed between
the gluteal folds when the side-lying position is
assumed. While the filming is taking place, the client
is requested to breathe rapidly and then hold the
breath.34

contrast-mediated studies, can be performed. If a
fracture is suspected, appropriate measures must be
taken when positioning the client for x-rays so that
spinal cord injury (SCI) does not inadvertently
occur. The physician who ordered the study should
be consulted before removing braces or other
immobilizing devices.
Reference Values
Normal vertebral bodies; no abnormal curvatures or fracture of the spine

INTERFERING FACTORS

Problems with positioning when fractures are
suspected or if immobilizing devices are in place
Metal objects such as jewelry or clothing fasteners
within the x-ray field
INDICATIONS FOR SPINAL FILMS

Evaluation of back or neck pain of unknown
etiology for possible arthritis, spondylosis, or
spondylolisthesis
Diagnosis of tumor or destruction of vertebral
bodies caused by malignancy or evidence of
spread of cancer to the spine35
Suspected or known vertebral fracture
Abnormal curvatures of the spine, such as scoliosis and kyphosis, in children
Monitoring of progression or treatment of scoliosis or lordosis
Determination of congenital spinal cord defects
in infants
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus

NURSING CARE AFTER THE PROCEDURE

NURSING CARE BEFORE THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Assess fetal heart sounds and signs of progression
of labor, if appropriate.

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Consult the physician before removing braces or
other immobilizing devices.
THE PROCEDURE

SPINAL FILMS
Various segments of the spine can be examined radiologically, including the cervical, thoracic, and
lumbosacral spine (Fig. 17–5). In most cases, such xrays are taken because the client is experiencing
pain. If spinal films are negative for abnormality,
additional diagnostic procedures, such as CT or

The client is placed on the x-ray table in a supine
position. First, an AP film is taken. The client is then
placed in the side-lying position and additional
lateral and oblique views are filmed.36 The oblique is
performed by angling the x-ray beam between AP
and lateral views. Fracture sites are immobilized
during the procedure to prevent further injury to the

CHAPTER 17—Radiologic

Studies

407

Figure 17–5. Thoracic and
lumbosacral spine and rib cage.

spine. The client should be instructed to report any
discomfort during the study.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Reapply braces or other appliances or devices, and
inform the client of any activity restrictions.

EXTREMITY FILMS
Films of all or part of the arms and legs are used to
diagnose a variety of skeletal conditions, including
fractures and other bone and joint disorders (Fig.
17–6). Positioning is important to obtain the desired
views; in some cases, orthopedic devices, joint
mobility, and client discomfort can interfere with
filming and clear imaging. The physician who
ordered the study should be consulted before splints
or other immobilizing devices are removed.
Reference Values
Normal bone, bone ossification, and joint structure; no fractures, dislocations, or congenital
anomalies involving bones or joints

INTERFERING FACTORS

Problems with positioning caused by orthopedic
devices, joint mobility, or client discomfort
Metal objects within the x-ray field
INDICATIONS FOR EXTREMITY FILMS

Evaluation of bone and joint pain of unknown
etiology for possible arthritis or other degenerative or malignant disorders of the bone
Suspected fracture of a bone, joint dislocation, or
fluid accumulation
Monitoring of fracture reduction and healing
process
Detection of changes in bone caused by infectious
diseases such as osteomyelitis
Monitoring of response to treatment for various
bone and joint disorders
Evaluation of skeletal trauma in younger children
Evaluation of growth pattern revealed by wrist
ossification
Determination of alterations in alignment and
configuration of the epiphysis after skeletal injury
Diagnosis and monitoring of improvement after
corrective interventions for congenital hip dysplasia and talipes deformities in infants

408

SECTION II—Diagnostic

Tests and Procedures

Figure 17–6. Bones of the extremities. (Left) Arm and hand. (Right) Leg and foot.

CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Consult the physician before removing any splits
or immobilizing devices.
THE PROCEDURE

The client is placed on the x-ray table with the
extremity to be studied in an appropriate position.
Films can also be taken with the client is a sitting
position. All injured parts are handled gently and
supported when moved or repositioned. A shield
is placed over the abdomen and testicular area
to protect the reproductive organs from radiation. Pillows, sandbags, and other immobilizing
devices are used to position or immobilize a body
part. Usually several different views of an area are
filmed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).

Reapply any immobilizing devices.
Administer a mild analgesic for discomfort and
heat application to a painful joint if ordered.37
Inform the client of any activity restrictions after
the procedure.

DUAL ENERGY X-RAY ABSORPTIOMETRY
(DUAL X-RAY ABSORPTIOMETRY)
Approximately 1.3 million fractures that occur each
year are attributed to osteoporosis.38 Risk factors for
osteoporosis include female gender, advanced age,
and poor intake of dietary calcium. Bone mass
density (BMD) can be measured to determine an
individual’s degree of osteoporosis and subsequent
risk for fractures. BMD can be measured by dual
energy x-ray absorptiometry (DEXA), also referred
to as dual x-ray absorptiometry (DXA). This is the
most sensitive noninvasive procedure for measuring
bone density. A combination of lateral spine and hip
scanning is the most efficient and cost-effective technique.39 Recently, portable scanners measuring bone
density in the forearm and heel have been developed. The advantages of these devices are their
portability and lower cost without significant
compromise of the ability to evaluate risk of fracture. Reference values are calculated using a T score
of bone density for a young normal mean (not age

CHAPTER 17—Radiologic

Studies

409

Reference Values
Diagnostic Category

T Score

Normal

1 SD

Osteopenia
Osteoporosis
Established osteoporosis

1 SD and 2.5 SD
2.5 SD (without fractures)
2.5 SD (with fractures)

From World Health Organization Criteria for Osteoporosis.

adjusted), and BMD is reported as standard deviations (SD) from that mean score.40
INTERFERING FACTORS

Problems with positioning of individuals with
scoliosis or kyphosis
Metal objects such as jewelry or clothing fasteners
causing imaging artifacts
INDICATIONS FOR DEXA SCANS

Evaluation of osteoporosis and risk of fracture
Suspected metabolic bone disease
CONTRAINDICATIONS

Recent (5 days) oral administration of contrast
dye agent
Recent (2 days) nuclear medicine scan
NURSING CARE BEFORE THE PROCEDURE

Teaching and physical preparation are the same as
for any plain x-ray procedure (see section under
“Skull Films”).
Assess client history for osteoporosis, estrogen
deficiency, vertebral abnormality, primary hyperthyroidism, corticosteroid therapy, anorexia
nervosa, chronic renal failure, ovarian or testicular hyperfunction, and rheumatoid arthritis.
THE PROCEDURE

The client is placed in a supine position on the x-ray
table. When positioning the client for PA scan of the
spine, the technologist should make sure that the
client’s spine is centered and straight and that the
iliac crests are visible. For a hip scan, the femoral
shaft should be straight and the hip internally
rotated. For the forearm, the extremity should be
straight and the distal ends of the radius and ulna
visible.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).

CARDIAC FILMS
Cardiac films involve the evaluation of cardiac
diseases and disorders by providing images of the
size, position, and contour of the heart and great
vessels. The cardiac series includes a barium swallow
with subsequent views of the heart with the client
in various positions, which provides a constant
view, by fluoroscopy, of the heart in motion and of
pulsations of the heart and great vessels during
systole and diastole phases.41 Filming of the heart in
motion exposes the client to a higher level of radiation and has generally been replaced by echocardiography.
Reference Values
Normal size, shape, and position of the heart
and great vessels; normal movement of the heart
during systole and diastole
INTERFERING FACTORS

Improper positioning, especially for views taken
by portable x-ray equipment with the client in
bed
Improper adjustment of the x-ray equipment to
accommodate obese and thin clients, resulting in
overexposure or underexposure and poor-quality
films
Inability of client to take deep breaths during
filming or to maintain a position without moving
Metal objects such as jewelry or clothing fasteners
within the x-ray field
INDICATIONS FOR CARDIAC FILMS

Evaluation of heart size, contour, and position for
abnormalities indicating a cardiac disorder
Observation of heart motion and pulsations by
fluoroscopic viewing to determine the presence of
aneurysm, congenital heart disorder, or valve
disorder
Evaluation of prosthetic valve function

410

SECTION II—Diagnostic

Tests and Procedures

Determination of calcifications within the heart,
especially of the valves
Suspected pericardial effusion or other abnormalities involving the area surrounding the heart
Evaluation of the placement and positioning of
pacemaker wires and cardiac catheters42
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Inform the client that a barium contrast medium
is administered orally if a cardiac series is to be
performed.
THE PROCEDURE

For routine, plain cardiac films or portable cardiac
films, the procedure is the same as for routine or
portable chest x-rays (see section under “Chest
Films”). Films of infants are taken in the supine
position. If fluoroscopic examination is performed
to visualize movement of the heart or to verify pacemaker wires or catheter placement, the client is
assisted to the best positions for viewing heart
movement from four directions.43 If a cardiac series
is to be performed, a barium swallow is given and
PA, lateral, right oblique, and left oblique views are
taken.44 The series allows better visualization of the
aortic arch and left heart enlargement, revealed by
esophageal deviations.45
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Place the client in a position of comfort and
replace all tubes or wires in their proper position
if a portable film is taken.
If the cardiac series was performed, administer a
laxative to assist in the elimination of the barium.

CHEST TOMOGRAPHY
Tomograms of the chest are valuable when the
nature of lesions seen on routine chest x-rays must
be determined or when routine films are negative
but an abnormality is suspected. Tomography
provides an image of the organ at different depths
and angles and reveals parts not seen on plain radiographs. Because the client is exposed to more radiation than with plain x-ray filming, tomography is
used only when absolutely necessary. This procedure
has been replaced by computed tomography of the
chest.46,47
Reference Values
Normal lung fields, mediastinal structures, ribs,
and thoracic spine
INTERFERING FACTORS

Inability of client to maintain required positioning and remain still during the study
Improper positioning of the client
Metal objects such as jewelry or clothing fasteners
within x-ray field
INDICATIONS FOR CHEST TOMOGRAPHY

Further evaluation of abnormal pulmonary
vasculature seen on chest x-ray
Suspected lung tumor when plain chest films are
negative
Further evaluation of abnormal results of plain
films of the chest that can include tuberculous
cavitation, lung abscess, or calcifications
Suspected tumor involving mediastinal structures, ribs, and spine48
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).

TOMOGRAPHY

THE PROCEDURE

Tomography provides a two-dimensional image
with clarity superior to that of plain films. It is especially valuable in visualizing air-filled structures
such as the lungs and paranasal sinuses. The studies
are contraindicated during pregnancy, unless the
benefits of performing the procedure far outweigh
the risks to the fetus.

The client is placed on the x-ray table in a supine
position. Side-lying or prone positions can also be
used for this study. The x-ray tube overhead is
moved back and forth in a circular or a figure 8
motion while the films are being taken. The client is
requested to remain very still on the table but to
breathe in a normal pattern.

CHAPTER 17—Radiologic

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).

PARANASAL SINUS TOMOGRAPHY
Tomograms of the paranasal sinuses produce images
in sections, making views possible that are not
obstructed by structures surrounding the sinuses.

Studies

411

same as for any plain x-ray procedure (see section
under “Skull Films”).

XERORADIOGRAPHY
The technique for xeroradiography, as described in
the “Introduction” section of this chapter, provides a
photoelectric view of the organ tissue, especially soft
tissue of the type found in the breasts.

MAMMOGRAPHY
Reference Values
Normal sinuses; no bony abnormalities, masses,
or foreign bodies

INTERFERING FACTORS

Inability of client to remain motionless during the
study while filming is taking place
Improper positioning for the desired views
Metal objects such as dental or eye prostheses or
eyeglasses within the x-ray field
INDICATIONS FOR PARANASAL SINUS
TOMOGRAPHY

Further evaluation of abnormal results of plain
films that reveal evidence of tumors, cysts, or fracture
Suspected fracture or tumor of the nasal bones
and bones surrounding the sinuses when plain
films are negative49
Detection of foreign bodies in the sinuses
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
THE PROCEDURE

The client is seated in a special chair with the head
immobilized in a padded brace or vise to maintain a
proper position. The client is requested to remain
very still while an x-ray tube overhead is moved in
different directions around a pivot point during
filming. Several views can be taken, depending on
the purpose of the study.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the

Mammograms are performed primarily to detect
malignancy of the breast. They can also be
performed to aid in determining the nature of
palpable lesions and to detect breast lesions in
women whose breasts are large, pendulous, and
difficult to examine adequately by palpation. A
signed informed consent form is required for this
procedure.
Mammography is usually performed using
xeroradiography, which is believed to have a
comparatively low radiation exposure level,
although newer conventional x-ray filming now
allows minimal exposure to radiation. The method
selected is mostly a matter of physician preference.
Mammography allows detection of breast tumors
less than 0.5 cm in diameter 2 to 3 years before they
are clinically evident; it carries an 85 percent accuracy rate and less than a 10 percent false-positive rate
in the diagnosis of carcinoma.50 Positive mammography results are confirmed by biopsy but can be
further studied by ultrasonography or diaphanography (transillumination).51 Transillumination is not
as reliable as conventional mammography in the
diagnosis of breast malignancy but is valuable in the
diagnosis of benign tumors and fibrocystic disease,
as well as in the evaluation of silicone-injected or
-augmented breasts.52
The American Cancer Society recommends that
all women between the ages of 35 and 40 years have
a baseline mammogram. From ages 40 to 49 years, a
mammogram should be performed every 1 to 2
years, depending on the client’s history. For example,
women with fibrocystic breast disease, previous
mastectomy, cancer of other organs, or family
history of breast cancer are advised to have yearly
mammograms. After the age of 50 years, it is recommended that all women have an annual mammogram.
Many women find mammography an embarrassing and uncomfortable procedure. Those who have
cystic disease should have the procedure performed
1 week after menses, when tenderness is decreased.
For some who find the procedure painful, a mild

412

SECTION II—Diagnostic

Tests and Procedures

analgesic can be administered before the study. Also,
many women are anxious about the procedure
because of the possibility of malignancy. Effective
client preparation and support are essential. The
importance of performing breast self-examination
(BSE) and having regular mammograms should also
be stressed. If detected early enough, breast cancer
has a high cure rate.
Note that, if a disease involving the mammary
ducts is suspected, mammography can be performed
after a contrast medium is injected into the ducts.
This is done to identify papillomas or ductal
obstruction.
Reference Values
Normal breast tissue; no cysts, tumors, or
abnormal calcifications

INTERFERING FACTORS

Powder, creams, perfumes, lotions, or underarm
deodorant on the skin
Extremely nodular breasts or previous surgery on
the breasts53
Inability to adequately compress the breasts or to
include all of the breast tissue in the films
Hematoma, mastitis, or papillomatosis if a transillumination study is performed54
Metal objects such as jewelry or clothing fasteners
within the x-ray field
INDICATIONS FOR MAMMOGRAPHY

Early detection of malignant tumors of the breast
before they are large enough to be palpated
Previous surgery for breast cancer, history of
cancer involving other organs, or both
Family history of breast cancer, cancer involving
other organs, or both
Evaluation of lumps or areas of thickening tissue
detected on BSE or by health-care practitioner on
clinical examination
Determination of cause of painful breasts
Diagnosis of breast cancer revealed by irregular
masses with poorly defined borders, extension
into surrounding tissue, or both conditions, or
abnormal calcifications in breast or ductal
tissue55,56
Diagnosis of fibrocystic disease of the breasts with
benign cysts revealed by round, smooth masses
with well-defined borders
Diagnosis of mastitis and breast abscess when
symptoms are evident
Evaluation of nipple and skin changes on breast
and association with malignancy

Routine screening procedure for breast cancer
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
study greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Instruct the client to avoid application of any
substance to the skin of the breasts, chest, or
underarms, and administer a mild analgesic if
pain is experienced when breasts are manipulated
or compressed.
THE PROCEDURE

The client is placed in front of the x-ray machine in
a standing or a sitting position. The machine is
adjusted to the level of the breasts. One at a time, the
client’s breasts are positioned on a flat plastic or
metal holder and compressed without creases or
wrinkles under the compression apparatus. If
xeroradiography is used, four views can be taken,
including oblique, lateral, chest wall, or vertical
(craniocaudal). A minimum of two views of each
breast is taken; one is usually chest wall. If conventional x-ray is used, three views can be taken, including oblique, lateral, or vertical, with a minimum of
two views of each breast, of which one view is
usually oblique. The arm is positioned upward and
out of range of the area to be x-rayed. The actual
filming takes place while the client takes a deep
breath and holds it. The client is requested to wait
while the films are developed and checked to be sure
that all the breast tissue was included in the views.
Diaphanography or transillumination is
performed in a dark room with the client in a sitting
position and the torso leaning forward. The examiner directs an infrared lighting device over each
breast. The light is filtered by the breast and densities
are converted into images. The images produced by
the light are photographed by a computerized
camera that is focused on the area.57 Films are developed and reviewed to provide diagnostic information.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plain x-ray procedure (see section
under “Skull Films”).
Teach the client BSE and provide brochures
outlining the procedure and the signs and symptoms to report. Stress the importance of regular
mammography, depending on the client’s age.

CHAPTER 17—Radiologic

CONTRAST-MEDIATED STUDIES
Contrast-mediated studies are performed to visualize soft tissues that produce poor images on x-ray
unless they are enhanced in some way. The most
commonly used contrast media are barium sulfate
and the organic iodides. These substances are
radiopaque and block the passage of the x-rays,
resulting in the images on film. Signed informed
consent forms are not obtained for procedures using
a barium contrast medium but are required for
those using iodinated contrast medium. The risks or
complications associated with the use of either
medium are outlined in the “Introduction” section
of this chapter.

BARIUM SWALLOW
A barium swallow (esophagography) involves the
recording of radiographic images of the esophageal
lumen while the client swallows barium solution.
The test is performed using fluoroscopic and cineradiographic techniques and is recorded on film or
videotape to evaluate both motion and anatomic
structures. A barium swallow is often performed
along with an upper gastrointestinal series. It is also
performed as part of a cardiac series to visualize the
size and shape of the heart and great vessels (see
“Cardiac Films” section).
Barium sulfate solutions of both thick and thin
consistencies are given. A swallowed small cotton
ball soaked in barium can be used to detect foreign
bodies in the esophagus, because swallowing liquid
barium occurs too rapidly for such objects to be
visualized.58 Food items can also be coated with
barium to evaluate both chewing and swallowing.
Barium is not used if perforation or obstruction of
the esophagus is suspected, because deposition of
the barium in soft tissues can cause a serious inflammatory response. In such cases, a water-soluble solution of an iodinated contrast medium such as
diatrizoate meglumine (Gastrografin) is used. Note,
however, that some of these materials are irritating
to the mucosa of the tracheobronchial tree and
should not be used when tracheoesophageal fistula
is suspected.59

Reference Values
Normal peristalsis through the esophagus into
the stomach with normal size and shape of the
esophagus; no inflammation, strictures, ulcerations, polyps, tumors, rupture, foreign bodies,
varices, or hiatal hernia

Studies

413

INTERFERING FACTORS

Inability of client to assume or remain in the
proper position during the procedure
Inability of client to swallow radiopaque
substance or barium-coated items
Foods and fluids ingested within 8 hours of the
study
Metal objects within the x-ray field
INDICATIONS FOR BARIUM SWALLOW

Chronic difficult or painful swallowing (dysphagia), heartburn, or regurgitation of food60
Suspected esophageal motility disorders such as
achalasia, spasms of the esophageal muscles
Diagnosis of esophageal reflux revealed by barium
returning to the esophagus from the stomach
Suspected strictures, polyps, Zenker’s diverticulum, benign or malignant tumor of the esophagus
Determination of whether sharp foreign object is
caught in the esophagus after accidental swallowing
Diagnosis of inflammatory or infectious process
such as acute or chronic esophagitis
Suspected congenital abnormality in infants such
as tracheoesophageal fistula or atresia
Suspected rupture of the esophagus (the study
must be performed with extreme caution)
Suspected esophageal varices, although they are
more likely to be detected by endoscopic procedures
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodine, if an iodinated contrast medium
is used
Suspected presence of intestinal obstruction
Suspected esophageal rupture, unless water-soluble iodinated contrast medium is used
Suspected tracheoesophageal fistula, unless
barium sulfate is used
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That a physician or a technician will perform the
study
That the procedure requires about 45 minutes to
1 hour
That foods and fluids are withheld for at least 8
hours before the procedure and should continue
to be restricted until the study has been
completed
That the client will be requested to swallow a
flavored barium solution while standing in front

414

SECTION II—Diagnostic

Tests and Procedures

of a fluoroscopy x-ray screen and that films will be
taken while the barium moves down the esophagus
That no pain is associated with the procedure,
although swallowing of the contrast medium can
be unpleasant
Prepare for the procedure:
Obtain a history to ascertain the date of the last
menstrual period and pregnancy status, possible
allergy to iodine if an iodinated contrast medium
is to be used, assessment of gastrointestinal system
for signs and symptoms, treatment and medication regimen, and associated diagnostic tests and
procedures.
Ensure that dietary and fluid restrictions have
been followed.
Ensure that all jewelry and clothing are removed
from the waist up and provide the client with a
gown without metal closures.
Assess baseline vital signs to compare with later
readings or to determine any deviations that can
warrant postponement of the study.
THE PROCEDURE

The client is helped onto the x-ray table in a supine
position or into a standing position in front of the xray screen. An initial plain film is taken. The client
stands in front of a fluoroscopic screen and is
requested to swallow a barium solution with or
without a straw. If the client has problems with
chewing or swallowing, small food items coated with
barium can be offered. A water-soluble iodinated
contrast medium can be used if a rupture of the
esophagus is suspected. Barium sulfate, which does
not react with the surrounding mucosa, is used if
tracheoesophageal fistula is suspected.61
The passage of the contrast material through the
esophagus is evaluated using fluoroscopic and
cineradiologic techniques, and spot films are taken
at different angles. The upright position facilitates
the diagnosis of strictures or obstructions of the
esophagus.62 The client is then strapped to the table
and the table rotated or tilted into the head-down
position, or the client is placed in the prone, supine,
and lateral positions for additional films. The client
may be requested to drink additional barium as
these films are taken. Delayed films can also be taken
to evaluate esophageal abnormalities caused by failure of the barium to completely pass through the
esophagus into the stomach.
NURSING CARE AFTER THE PROCEDURE

Resume food and fluids if no additional films are
to be taken.

Monitor vital signs and compare with baselines
for changes that indicate complications.
Administer, or advise client to take, a mild laxative
and increase fluid intake to aid in the elimination
of the barium.
Inform the client that feces will be whitish or light
in color for 2 to 3 days and to notify the physician
if the normal color does not return or if the client
is unable to eliminate the barium.
Reaction to iodinated contrast medium: Note
and report tachycardia, hyperpnea, palpitations,
or hypertension. Administer ordered antihistamine or steroid. Initiate IV line and resuscitation
procedure, if needed (see Table 17–1).

UPPER GASTROINTESTINAL SERIES
An upper gastrointestinal (UGI) series involves radiologic examination of the lower esophagus, stomach, duodenum, and upper jejunum after ingestion
of a solution of barium sulfate. The entire small
bowel can also be evaluated by this study. The
procedure is then referred to as a UGI with smallbowel follow-through. A combination of x-ray and
fluoroscopic techniques is used to perform the study.
Fluoroscopic techniques are used to visualize
passage of the barium from the esophagus into the
stomach and from the stomach into the duodenum.
A complete examination of the small intestine by
fluoroscopy can also be made in addition to the
UGI. This study involves visualization of the small
bowel up to the ileocecal valve by taking films at
specific time intervals (usually every 10 minutes) as
the barium passes through the small intestine. A
more detailed evaluation of the small bowel can be
accomplished by a procedure known as the smallbowel enema. X-ray filming can also be used to
obtain spot films of various areas of the UGI tract.
As with barium swallow, solutions of barium should
not be used if perforation of the stomach or duodenum is suspected, because deposition of barium in
soft tissues can cause a serious inflammatory
response. In such cases, a water-soluble solution of
an iodinated contrast medium, diatrizoate meglumine, is used.

Reference Values
Normal esophageal, stomach, and small intestine motility; normal size and shape of the stomach and small intestine; no ulcerations,
inflammation, tumors, strictures, ruptures,
foreign bodies, or hiatal hernia

CHAPTER 17—Radiologic

INTERFERING FACTORS

Inability of client to assume or remain in the
desired position for the procedure
Inability of client to ingest the radiopaque
substance
Foods and fluids ingested within 8 hours of the
study that affect peristalsis
Medications such as anticholinergics and
narcotics that affect motility
Barium remaining in the tract from other studies
using the contrast medium
Metal objects within the x-ray field
INDICATIONS FOR UPPER GASTROINTESTINAL
SERIES

Persistent epigastric pain or heartburn of
unknown etiology
Possible strictures or varices in the lower esophagus
Hematemesis or presence of blood in the feces
Unexplained weight loss, anorexia, nausea, or
vomiting
Palpable mass in the epigastric area63
Persistent abdominal pain or diarrhea of
unknown etiology
Possible peptic ulcer disease
Suspected tumor of the stomach or small bowel
Inflammatory disorder of the stomach or small
bowel
Diagnosis of obstruction or malabsorption
syndrome and fistula or ulcerations of the small
bowel revealed by diminished or increased motility64
Congenital anomalies such as pyloric stenosis in
children
Malrotation causing bowel obstruction in infants
Suspected hiatal hernia
Suspected foreign body in the UGI tract
Evaluation of treatment regimen for gastrointestinal diseases
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodine, if an iodinated contrast medium
is used
Clients who are combative or generally uncooperative
Evidence of or suspected intestinal obstruction
Suspected rupture involving the stomach or small
intestine, unless the study is performed with
caution and with a water-soluble iodinated
contrast medium

Studies

415

NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Barium Swallow”
section.
Inform the client that medications that interfere
with gastric motion are withheld for 12 to 24
hours, that filming can take as long as 5 hours,
and that it may continue the next day to evaluate
small-bowel function in those with decreased
peristalsis.
THE PROCEDURE

The procedure varies slightly, depending on the
institution. The client can be placed on the x-ray
table in a supine position for an initial plain abdominal film. The client is then assisted to a sitting or
standing position or is strapped to the table, tilted
into a vertical position, and given 8 to 16 oz of
barium solution to drink. The client is informed that
the solution is flavored and chalky in consistency
and not too pleasant to drink. The passage of the
barium through the esophagus, stomach, and
duodenum is filmed and evaluated by fluoroscopy as
the client drinks the barium solution. Visualization
can be improved by using both air and barium as
contrast agents (“double-contrast” study). For this
method, the client sips the barium through a perforated straw, which allows both barium and air to be
introduced into the stomach and promotes viewing
by smoothing the ridges of the gastric rugae.65
After complete ingestion of the barium solution,
films are taken in various positions, including
supine, side-lying, and prone. PA, AP, lateral, and
oblique views are taken. Pressure can be applied to
the epigastric area to ensure adequate coating of the
stomach with the barium or to straighten overlapping bowel loops. Filming takes place throughout
the procedure, and additional barium can be given
to ensure adequate coating of the small intestine if a
small-bowel series is done. Small-bowel filming is
performed at 15- to 30-minute intervals until the
barium reaches the cecum.
If a small-bowel enema study is conducted, a
barium solution is injected into an enteral tube
placed into the duodenum via the mouth or endoscope and films taken as in the small-bowel series.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those described in the “Barium Swallow”
section.
Advise the client that diarrhea can occur if a
water-soluble contrast medium was administered.
Barium aspiration: Note and report choking or

416

SECTION II—Diagnostic

Tests and Procedures

any change in respiratory pattern. Perform
orotracheal suction. Provide ordered oxygen.
Prepare for intubation, if needed.

BARIUM ENEMA
Barium enema (BE), or lower gastrointestinal (LGI)
series, involves radiologic examination of the colon
after the instillation of barium via a rectal tube
inserted into the rectum or an existing ostomy. A
combination of x-ray and fluoroscopic techniques is
used to perform the study. Fluoroscopic techniques
are used to visualize passage of the barium through
the large intestine. X-rays are taken to obtain spot
films of various areas of the colon. Visualization can
be improved by using both air and barium as the
contrast agents. This procedure is known as a
double-contrast study and is especially useful in
improving detection of small lesions and polyps. As
with the barium swallow and UGI series, barium
solutions should not be used if perforation of the
colon is suspected, because leakage of barium can
cause a serious inflammatory response. In such
instances, a water-soluble solution of an iodinated
contrast medium such as diatrizoate meglumine is
used.
For the procedure to be successful, the bowel
must be cleared of fecal matter or barium from
previous studies. Various approaches are used to
cleanse the bowel, as outlined in the following
“Nursing Care Before the Procedure” section, with
modifications made for young children, elderly
clients, and clients with an ostomy or a history of
colitis.66
The proper sequencing of the gastrointestinal
studies in which barium is used as the contrast
medium is also important. Barium enema should be
performed before the UGI series, which in turn
should be performed before the barium swallow, if
the UGI series and barium swallow are performed as
separate studies. Privacy and comfort are preserved:
Most clients find barium enemas uncomfortable and
embarrassing procedures. Effective preparation and
support for this study are essential to ensure that the
procedure will not require repetition.
Reference Values
Normal size, shape, and motility of the colon; no
inflammation, tumors, polyps, diverticula,
congenital anomalies, or foreign bodies
INTERFERING FACTORS

Inability of client to assume or remain in the
desired position

Inability of client to tolerate introduction of or to
retain barium, air, or both, in the bowel
Residual barium or excessive feces in the bowel
resulting from inadequate cleansing or failure to
restrict food intake before the study
Colon spasms that impair visualization67
Metal objects within the x-ray field
INDICATIONS FOR BARIUM ENEMA

Rectal bleeding of unknown etiology
Unexplained blood, pus, or mucus in the feces
Change in bowel patterns that leads to chronic
diarrhea, constipation, or caliber of feces
Unexplained weight loss or anemia
Persistent abdominal pain or distention of
unknown etiology
Identification of benign and malignant polyps
and tumors
Evaluation of genitourinary malignancies to
determine metastasis to the colon
Identification of diverticula, megacolon, or other
structural changes
Suspected inflammatory process of the colon and
of the terminal ileum, such as colitis, ulcerative
colitis, or Crohn’s disease
Suspected abnormality in bowel motility and
obstructions of the bowel
Suspected congenital anomaly involving the
bowel
Reduction of intussusception in children
Suspected foreign body in the colon
Evaluation of colon surgery
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodine, if an iodinated contrast medium
is used
Evidence of intestinal obstruction
Evidence of toxic megacolon, acute ulcerative
colitis, acute diverticulitis, or other acute colon
disorder68
Suspected rupture involving the colon, unless
performed with caution using a water-soluble
iodinated contrast medium
NURSING CARE BEFORE THE PROCEDURE

Client teaching and preparation are the same as
those described in the “Barium Swallow” section,
except that this study requires 45 to 90 minutes.
Dietary regimen and bowel preparation vary with
institutions.
Instruct the client to follow a low-residue diet for
several days before the procedure, to increase
fluids the day before, to ingest a clear liquid diet

CHAPTER 17—Radiologic

Nursing Alert

A client scheduled for several studies using
barium should have the barium enema
performed first because residual barium from
other studies can necessitate repeated bowel
preparation if an LGI series is performed as a
second study.
Lack of adequate fluid intake before or after
the study can cause dehydration if excessive
fluids are removed from the colon during
bowel preparation.
Use of laxatives or cathartics in bowel preparation can cause a life-threatening complication in the presence of obstruction, acute
ulcerative colitis, or diverticulitis.
the evening before, and to take nothing by mouth,
including medications, on the day of the procedure.
Instruct the client to take magnesium citrate
liquid and a bisacodyl tablet the evening before;
inform client that this preparation can cause
cramping and diarrhea.
Administer suppositories and cleansing enemas
before the procedure and evaluate their effectiveness (clear return of the enemas).
Be cautious in the use of enemas and laxatives on
children and elderly people, who are more prone
to fluid and electrolyte imbalances.
Inform clients with an ostomy to follow the same
dietary preparations, to take laxatives the evening
before, and to administer a colostomy irrigation
before the study.
Advise clients with an ostomy that the barium
enema is administered through a Foley catheter
introduced into the ostomy; clients should bring
an appliance and pouch system with them if they
are outpatients.69
THE PROCEDURE

The procedure varies slightly, depending on the
institution and approaches for children, elderly
clients, and clients with ostomies. The client is
placed on the x-ray table in a supine position for an
initial plain abdominal film. The client is then
assisted to a side-lying position and draped with the
anus exposed or to a comfortable supine position
and draped with the stoma exposed. A lubricated
rectal tube is inserted into the anus and a balloon on
the end of the tube is inflated after it is situated
against the anal sphincter.70 A Foley catheter is
inserted into the stoma if an ostomy is present. For
children or elderly clients, the buttocks can be taped

Studies

417

together or a special inflatable retention device can
be used.71
Barium is instilled into the colon. The client
should be informed that this procedure can cause
cramping, sensations of abdominal fullness, and the
urge to defecate. Encourage controlled breathing
and relaxation to aid in tolerance and retention of
the barium. The tube can be left in place after the
instillation is completed to assist in retention of the
barium until all the films are taken. Movement of
the barium through the colon into the ileocecal valve
and then into the terminal ileum is observed by fluoroscopy. The client is assisted into supine, prone,
side-lying, and erect positions while spot films are
taken for different views.
The procedure for performing double-contrast
studies to improve visualization varies with institutions. Double-contrast studies have a higher rate of
accuracy in detecting small lesions and polyps of the
colon. One method allows some of the barium to be
expelled or aspirated and for air to be injected to
distend the colon. Another method involves instilling barium into the descending colon and then
forcefully injecting air without removing any of the
barium.
When the films are completed, the barium is aspirated and the tube removed. The client is assisted to
the bathroom or placed on a bedpan to expel the
barium remaining in the colon. Another film can be
taken after the elimination of the barium.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those described in the “Barium Swallow”
section.
Encourage the client to increase fluid intake and
to rest if feeling fatigued.
Administer a tap water colostomy irrigation to
assist in the removal of the barium.
Fluid imbalance: Note and report signs and
symptoms of dehydration such as decreased
urinary output; warm, dry skin; or poor skin
turgor. Administer fluid orally or IV to replace
losses. Monitor electrolytes.
Perforation of colon: Note and report acute
abdominal pain, nausea, vomiting, or abdominal
distention. Administer ordered analgesic and
antibiotic therapy. Insert NG tube and attach to
suction. Prepare for possible surgery.

ORAL CHOLECYSTOGRAPHY
For an oral cholecystogram (OCG), the dye, usually
iopanoic acid (Telepaque) or ipodate sodium
(Oragrafin), is administered orally in tablet form.

418

SECTION II—Diagnostic

Tests and Procedures

The dye is subsequently absorbed in the small bowel,
transported to the liver, excreted by the liver into
bile, and concentrated in the gallbladder.72
Approximately 12 to 14 hours are required for this
process to occur.73 The dye is administered the
evening before the study. A low-fat diet is also given
so that the gallbladder does not contract and empty.
Gallstones are usually not visualized on plain
films unless they are calcified, which occurs in
approximately 10 percent of all cases of cholelithiasis.74 The concentration of dye in the gallbladder
allows the gallstones to appear as shadows on the xray film.75 In addition to the actual appearance of
gallstones on x-ray, gallstones can be suspected if the
gallbladder is not visualized after administration of
the dye; that is, gallstones can obstruct the bile ducts
and prevent the dye from reaching the gallbladder.
Failure to visualize the gallbladder can also be
caused by inflammation of the bile ducts, impaired
liver function, impaired absorption from the small
intestine, or inadequate dosage of the contrast
medium. Jaundice with elevated bilirubin levels is
also associated with diminished excretion of the dye
and impaired visualization of the gallbladder.76
The study is performed after any study involving
the measurement of iodinated compounds and
before any gastrointestinal study involving the use of
barium as the contrast medium. Ultrasound examination of the gallbladder is more sensitive than the
OCG in detecting gallstones and is replacing this
procedure as the diagnostic test of choice. Magnetic
resonance imaging (MRI) and CT scanning are also
used in selected situations.77
Reference Values
Normal appearance of gallbladder; no calcification of the gallbladder wall, stones, filling
defects, or abnormal accumulation of gas

Inability of the gallbladder to concentrate the dye
for visualization
Jaundice with bilirubin levels over 2 mg/dL and
with impaired excretion of the dye
Metal objects within the x-ray field

INDICATIONS FOR ORAL
CHOLECYSTOGRAPHY
Upper right quadrant (URQ) pain, right epigastric pain, or both, of unknown etiology
Evaluation of symptoms of cholecystitis and gallbladder function revealed by the gallbladder’s
ability to accumulate, concentrate, and expel the
dye
Suspected malignant tumor revealed by calcification of the gallbladder wall78
Suspected gallstones in the gallbladder or
obstructed cystic duct with gallstones, or both
conditions
Determination of the presence of papillomas,
adenomas, and diverticula of the gallbladder
Diagnosis of fistula between the biliary system
and the gastrointestinal tract revealed by gas in
the gallbladder or ducts79
Determination of congenital anomalies of the
gallbladder
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodine or history of allergy to contrast
material
Jaundice with bilirubin of greater than 2 mg/dL
Severe renal or hepatic insufficiency
Severe vomiting, diarrhea, or conditions that
affect absorption of the dye
Nursing Alert

INTERFERING FACTORS

Inability of client to maintain the required positions
Barium in the gastrointestinal tract
Inadequate dose of the oral contrast medium
Vomiting or diarrhea after administration of the
contrast medium
Failure to follow dietary restrictions
Impaired absorption of the dye from the gastrointestinal tract
Impaired liver function, resulting in failure to
excrete the dye into the bile
Cystic duct obstruction, preventing dye from
entering the gallbladder

A client scheduled for barium studies should
have an OCG first to prevent interference
from possible residual barium.
Clients who are scheduled for studies such as
thyroid procedures that involve the measurement of iodinated compounds should have an
OCG after these tests.
Inadequate fluid intake before the study can
lead to impaired renal function and excretion
of the dye.
Assessment and observations for allergic reactions to iodinated contrast medium should be
made on all clients (see Table 17–1).

CHAPTER 17—Radiologic

NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure requires about 1 hour but that
additional films may need to be taken 30 to 60
minutes after a high-fat meal
That a low-fat diet is to be eaten the evening
before the procedure and foods and fluids withheld after midnight
That the contrast material is ingested 2 hours
after the evening meal, with six tablets taken
with a full glass of water, one at a time, every 5
minutes80
That fluid intake should be increased during the
evening before midnight
That the tablets can cause vomiting, diarrhea,
abdominal cramping, and epigastric pain and that
any of these conditions should be reported immediately, because they can cause postponement of
the study
That any symptoms such as palpitations, difficult
breathing, or other complaints after ingestion of
the tablets should be reported immediately
That no pain is associated with the procedure
Prepare for the procedure:
Obtain a history to ascertain the date of the
last menstrual period and possible pregnancy,
allergy to iodine, known or suspected gallbladder or liver disorders, treatment regimen,
associated diagnostic tests and procedures that
include a serum bilirubin for levels greater than
2 mg/dL.
Ensure that the dietary requirements have been
followed and that fluid intake has been sufficient.
Ensure that the full dose of contrast material has
been ingested and retained; that is, no vomiting
or diarrhea has been experienced to indicate
that the dose is not adequate for the study to be
performed.
Administer an ordered suppository or enema to
clear the gastrointestinal tract of solid material,
even if a laxative was taken the evening before the
study.

Studies

419

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
monitoring for adequate fluid intake and urinary
output and allergic response to the dye.
Encourage extra fluid intake in clients with an
ostomy if bowel output increases as a result of the
laxative or enema effect of the dye.81
Instruct the client to resume a normal diet if the
study has been concluded.
Also, inform the client that the dye is excreted
through the kidneys but that the urine does not
change color.
Reaction to iodinated contrast medium: Note
and report anxiety, tachycardia, hyperpnea, or
palpitations. Administer ordered antihistamines
and steroids. Provide oxygen and initiate resuscitation, if needed (see Table 17–1).
Fluid–electrolyte imbalance: Note and report
excessive vomiting, diarrhea, and signs and symptoms of dehydration such as decreased urinary
output; hot, dry skin; and poor skin turgor.
Increase fluid intake orally or initiate IV fluid
replacement as ordered. Monitor electrolytes.

INTRAVENOUS CHOLANGIOGRAPHY
The intravenous cholangiogram (IVC) allows visualization of the biliary ducts. It is performed if the
gallbladder is not visualized on an OCG, if the client
cannot tolerate or is unable to absorb the oral preparation for OCG, or if symptoms persist after cholecystectomy. For this study, the iodinated contrast
medium iodipamide (Cholografin) is administered
IV. A combination of plain and tomographic films is
taken 15 minutes after the injection and periodically
for up to 8 hours. The dye aids in the visualization of
the hepatic and common bile ducts for stones, strictures, or tumors.82
Reference Values
Normal hepatic and common bile ducts; no
stones, strictures, or tumors

THE PROCEDURE

The client is placed on the x-ray table in the supine
position. A sequence of films of the URQ of the
abdomen is taken in prone, left side-lying, and
standing positions. The client can be given a high-fat
meal or a fatty substance to stimulate contraction
and emptying of the gallbladder. The response of the
gallbladder to the fat stimulus is evaluated by fluoroscopy. Additional plain films are also taken to
evaluate emptying of the gallbladder and movement
of the dye through the common bile duct.

INTERFERING FACTORS

Inability of client to maintain positions required
for the procedure
Barium or feces in the gastrointestinal tract
Failure to refrain from eating or drinking 8 to 12
hours before the procedure
Jaundice with a bilirubin level of greater than 2
mg/dL83
Metal objects within the x-ray field

420

SECTION II—Diagnostic

Tests and Procedures

INDICATIONS FOR INTRAVENOUS
CHOLANGIOGRAPHY

Failure to visualize the gallbladder with OCG
Inability of client to tolerate the oral preparation
or its absorption in the gastrointestinal tract with
OCG
Persistence of symptoms after cholecystectomy
Evaluation of the hepatic and bile ducts for
patency, which can be affected by the presence of
stones, tumor, or stricture
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodine or history of allergy to contrast
material
Severe renal or hepatic insufficiency
Jaundice with a bilirubin level of greater than 2
mg/dL
Nursing Alert

A client scheduled for gastrointestinal studies
that use barium should have the IVC first to
prevent interference in imaging caused by
residual barium in the tract.
A client scheduled for studies involving the
measurement of iodinated compounds as in
thyroid tests should have the IVC study
performed after such tests.
Inadequate fluid intake before the study can
lead to impaired renal excretion of the dye
and can adversely affect renal function.
Assessment and observation for allergic reactions to iodinated contrast medium should be
made on all clients (see Table 17–1).
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Oral Cholecystography” section.
Inform the client that the dye is administered IV
instead of orally and that the study can take up to
4 hours.
Advise the client that a sensation of warmth and
nausea can be experienced and, although temporary, it should be reported to the physician.
Initiate an IV line if ordered for administration of
the contrast medium.
Administer an ordered antihistamine or steroid
before the study, because toxic reaction to the dye
is more likely in this procedure than in OCG.84

THE PROCEDURE

The client is placed on the x-ray table in a supine
position and a plain abdominal film of the URQ is
taken. The IV line is initiated, if not already in place,
and the iodinated contrast material is administered
over a 30-minute period. This time allows the dye to
be excreted into the bile ducts by the liver. Films are
taken every 15 to 30 minutes in the prone, sidelying, and erect positions. When the gallbladder is
filled with dye, usually in 2 to 4 hours, additional
films are taken of the gallbladder biliary system.
Filming can continue at intervals until the common
bile duct is visualized. Tomographic evaluation can
be performed after visualization of the ducts.85
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those described in the “Oral Cholecystography” section.
Assess the venipuncture site for inflammation and
bruising.
Inform the client that some discomfort during
urination can be experienced as the dye is
excreted.
Monitor for a delayed reaction to the dye for 24
hours and remind the client to report nausea.
Phlebitis at injection site: Note and report
pain, swelling, and redness at the site. Elevate
and position arm on a pillow. Apply warm
compress.
Inflammation of bile duct: Note and report
chills, fever, and abdominal pain. Administer
ordered antipyretic and antibiotic therapy.
Monitor temperature and vital signs.

T-TUBE CHOLANGIOGRAPHY
The T-tube cholangiogram is performed approximately 7 to 10 days after gallbladder surgery to assess
the patency of the common bile duct and to detect
any remaining stones. It can, however, be performed
during surgery after placement of the tube to ensure
that all stones have been removed. For this study, an
iodinated contrast medium such as diatrizoate
meglumine-diatrizoate sodium (Hypaque) is
injected directly into the T-tube, followed by x-ray
and fluoroscopic examination.86 T-tubes are placed
during surgical exploration of the common bile duct
(Fig. 17–7). The end of the T-tube exits from the
abdomen through a stab wound and is connected to
gravity drainage. T-tube cholangiograms are
performed before removal of such tubes if no stones
are visualized and bile is flowing freely into the
duodenum.

CHAPTER 17—Radiologic

Studies

421

Figure 17–7. Placement of Ttube in common bile duct.

Nursing Alert

Reference Values
Normal biliary ducts; no stones, strictures,
fistula, or neoplasms
INTERFERING FACTORS

Barium in the gastrointestinal tract
Failure to follow dietary restrictions before the
procedure
Air injected into the biliary tract
INDICATIONS FOR T-TUBE CHOLANGIOGRAPHY

Evaluation of biliary duct patency before T-tube
removal
Detection of stones remaining in the biliary tract
after gallbladder surgery
Detection of fistula caused by surgical injury to
the duct
Detection of strictures and neoplasms of the
biliary tract
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodine or history of allergy to contrast
medium
Postoperative wound sepsis
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are
the same as those described in the “Oral Cholecystography” section.
Inform the client that the dye is injected into

A client scheduled for barium studies should
have T-tube cholangiography first to prevent
any interference in visualization.
A client scheduled for studies such as thyroid
studies to measure iodinated compounds
should have T-tube cholangiography after
these procedures.
Assessment and observation for allergic reactions to iodinated contrast media should be
made on all clients (see Table 17–1).
the T-tube, that the tube is clamped before the
filming, and that it remains clamped during the
study.
Bowel preparation may not be included before
this study.
THE PROCEDURE

The T-tube is clamped the day before the scheduled
study. The client is placed on the x-ray table in a
supine position and the area around the T-tube
draped for privacy concerns. The end of the T-tube
is cleansed with an antiseptic and held straight in a
vertical position. A needle that is attached to a tube
is inserted into the open end of the T-tube and the
clamp is removed. The contrast material is injected
into the T-tube, and fluoroscopy is performed to
visualize the dye moving through the duct system.
Inform the client that a feeling of slight pressure or
fullness can be experienced as the dye is injected, and
instruct the client to report any sensations of

422

SECTION II—Diagnostic

Tests and Procedures

warmth and nausea after the dye is injected. The
tube is clamped and films are taken of the URQ in
different positions, such as prone, side-lying, and
erect. An additional film can be taken 15 minutes
later to visualize the passage of the contrast medium
into the duodenum.87
The procedure is performed as early as 8 hours
or as late as 7 to 10 days after cholecystectomy
to determine whether the duct is patent and
whether the T-tube should be removed or left in
place. The total procedure is usually completed
within 30 minutes, depending on biliary tree visualization.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those described in the “Oral Cholecystography” section.
Monitor the T-tube insertion site for pain,
swelling, or redness. If the tube is left in place,
apply a skin protector ointment and sterile dressing taped in place around the T-tube.
Unclamp the tube and attach to a sterile closed
drainage system.

OPERATIVE CHOLANGIOGRAPHY
The operative cholangiogram is performed during
gallbladder surgery to visualize the biliary ducts and
assess for the presence of gallstones, strictures, or
tumors that can affect the patency of these structures.88 For this study, an iodinated contrast
medium, usually diatrizoate meglumine-diatrizoate
sodium, is injected directly into the cystic or
common bile duct with a needle or catheter. It allows
the surgeon to view the ducts by x-ray examination
to correct abnormalities and ensure that no injury to
the ducts has occurred before the surgical procedure
has been completed.
Reference Values
Normal biliary tract; no stones, strictures, or
tumor to obstruct flow of bile

INTERFERING FACTORS

Instruments or other metal objects within the xray field
INDICATIONS FOR OPERATIVE CHOLANGIOGRAPHY

Evaluation of biliary ducts for anatomic abnormalities such as tumors, strictures, or stones that
prevent flow of bile during the cholecystectomy
surgery

Detection of stones in the cystic duct during
surgery89
Detection of trauma to the bile duct during exploration at the time of surgery
Suspected pancreatitis
Presence of jaundice and increase in hepatic
enzymes
CONTRAINDICATIONS

Allergy to iodine or history of allergy to contrast
medium
NURSING CARE BEFORE THE PROCEDURE

There are no client teaching and physical preparations other than those already carried out for the
cholecystectomy because the procedure is
performed during surgery.
THE PROCEDURE

During the cholecystectomy procedure, the
common bile and cystic ducts are explored. A
catheter is inserted into the common bile duct and
the dye injected into the catheter. X-rays are taken,
developed immediately, and viewed by the surgeon
for the presence of abnormal structure, obstructive
lesions, or stones in the ducts. Exploration of the
ducts can be performed, based on the findings of
stones in the ducts and stone removal to ensure
patency for normal flow of bile into the duodenum.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
routine postoperative care.
Monitor the client for delayed adverse effects of
the contrast medium and for signs and symptoms
of an infectious process caused by injection of the
material into the ducts.

PERCUTANEOUS TRANSHEPATIC
CHOLANGIOGRAPHY
The percutaneous transhepatic cholangiogram
(PTHC) allows visualization of the intrahepatic,
extrahepatic, and biliary ducts, as well as the gallbladder, to determine obstruction to biliary flow
caused by stones, tumor, stricture, congenital anomalies, or anatomic abnormalities.90 It is most
commonly performed on clients with jaundice to
determine whether or not the cause can be attributed to obstruction of the ducts. For this study, the
iodinated contrast medium is administered through
a long, fine needle inserted into the liver and, with
the aid of fluoroscopy, into a bile duct (Fig. 17–8).
Fluoroscopic examination of the ducts is made and
spot films taken in various positions.

CHAPTER 17—Radiologic

Studies

423

Figure 17–8. Placement of
needle in the bile duct in the liver.

Reference Values
Normal biliary ducts; no obstruction or deviation of the common bile duct; no anatomic
abnormalities or dilated ducts
INTERFERING FACTORS

Inability of client to remain still and maintain the
position required to perform puncture
Barium in the gastrointestinal tract
Obesity
Failure to follow dietary restrictions before the
procedure
Metal objects within the field
INDICATIONS FOR PERCUTANEOUS TRANSHEPATIC
CHOLANGIOGRAPHY

Evaluation of URQ after cholecystectomy
Differentiation between obstructive and nonobstructive cause of jaundice
Determination of the cause of obstruction of the
ducts, such as stones, tumor, cysts, or strictures
and whether the obstruction is partial or
complete
Diagnosis of biliary sclerosis or sclerosing cholangitis
Determination of congenital or anatomic abnormalities of the ducts that can be the cause of an
obstruction
Determination of biliary duct abnormalities in
clients with previous gastrointestinal surgery that
results in endoscopic inaccessibility
Performing liver biopsy, if ducts are patent, when
hepatitis or cirrhosis of the liver is suspected as
the cause of jaundice
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the

procedure greatly outweigh the risks to the fetus
Client unable to cooperate
Allergy to iodine or history of allergy to iodinated
contrast material
Severe ascites, cholangitis
Uncontrolled coagulopathy with prolonged clotting time, prothrombin time (PT), and abnormal
coagulation factors panel
Nursing Alert

Assess and observe for intra-abdominal bleeding or bile leakage as a result of accidental
puncture of a large vessel. Symptoms include
abdominal pain, distention, and rigidity associated with peritonitis; hypotension; rapid,
thready pulse; and cold, clammy skin associated with hypovolemic shock.91
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Oral Cholecystography” section.
Advise the client that the study takes 30 minutes
to 1 hour.
Inform the client that the site is anesthetized by a
local injection and that some pain is experienced
when the liver is punctured.
Include the results of a complete blood count
(CBC), clotting time, PT or partial thromboplastin time (PTT), and blood typing and crossmatching in the preprocedure history and
assessment.
Advise the client to refrain from using any aspirin
products.
Administer ordered vitamin K based on an
increased PT.
Administer an ordered antibiotic and antihista-

424

SECTION II—Diagnostic

Tests and Procedures

mine to prevent infection and reaction to the
contrast medium. Administer an ordered intramuscular (IM) sedative and analgesic such as
diazepam (Valium) or meperidine (Demerol) for
anxiety and pain control.
THE PROCEDURE

The client is placed on the x-ray table in a supine
position with straps in place to prevent falling when
the table is tilted. The right upper abdomen is
exposed and the skin cleansed with an antiseptic
solution. The area is draped and the insertion site
injected with a local anesthetic, usually lidocaine.
The insertion site is chosen between the eighth and
ninth intercostal space at the midaxillary line to
avoid lung puncture and to place the needle near the
hilus of the liver. An IV line is initiated at this time
and a sedative administered with care so that the
client is not oversedated and is able to cooperate
when needed. A long, fine (21-gauge, 20-cm) needle
is inserted at the site and advanced in a smooth
motion into the liver under fluoroscopic guidance.
The client is requested to hold the breath during
insertion of the needle. When the needle attains its
desired position in the bile duct, the stylet is
removed and a syringe and tubing are connected to
the needle hub. Placement in a duct is evidenced by
the flow of bile, and the dye is injected. The client is
informed that a sensation of fullness or pressure can
be felt. Any nausea, flushing, or sweating after dye
injection should be reported to the physician immediately. The contrast material fills the branching
tubular structures as noted with the fluoroscopic
procedure. Biliary pressure can be measured at this
time. To reduce the risk of septicemia, only enough
contrast material should be injected to enable
proper viewing and diagnosis.92 Spot films are taken
and the table tilted for a side-lying and an erect view
for further filming. The needle is then removed and
a sterile dressing taped in place over the puncture
site. A catheter can be left in the biliary tract if an
obstruction is discovered so that the tract can be
drained and decompressed.93
NURSING CARE AFTER THE PROCEDURE

Have the client rest for 6 hours in a right sidelying position to relieve pressure on the injection
site.
Inform the client that some pain can be experienced in the abdomen and right shoulder.
Monitor vital signs until stable and compare with
baseline readings and monitor for changes indicating intra-abdominal bleeding.
Assess for possible peritonitis caused by bile leaking into the abdominal cavity.

If a catheter is placed in the tract, attach to a sterile closed drainage system.
Assess site for swelling, pain, and drainage because
some bleeding and drainage usually occur.
Resume food intake in 5 to 8 hours if condition
remains stable and no complications have developed.
Administer an ordered mild analgesic if it will not
mask more serious signs and symptoms of infection.
Reaction to iodinated contrast medium: Note
and report anxiety, feeling of warmth or flushing,
itching, urticaria, sweating, nausea or vomiting,
tachycardia, or hyperpnea. Administer ordered
antihistamine or steroid. Initiate resuscitation
procedure as needed.
Peritonitis and septicemia: Note and report
temperature elevation, chills, and abdominal
pain, distention, and rigidity. Administer ordered
antipyretics and antibiotics. Initiate IV line.
Monitor vital signs. Prepare for surgery if needed.
Intra-abdominal hemorrhage: Note and report
hypotension; rapid, thready pulse; cold, clammy
skin; abdominal distention. Obtain CBC and
typing and cross-matching. Administer blood
transfusion. Prepare for surgery if needed.

ANTEGRADE PYELOGRAPHY
The antegrade pyelogram allows visualization of the
kidney’s collecting system. It is performed if the
kidneys are unable to excrete dye administered for
intravenous pyelography (IVP), if ureteral obstruction is present, or if a cystoscopy procedure is
contraindicated.94 For this study, a fine percutaneous needle is inserted into the renal pelvis and the
iodinated contrast medium, diatrizoate sodiumdiatrizoate meglumine (Renografin), is injected
through tubing connected to the needle. Placement
of the needle and injection of the contrast material
are accomplished under the guidance of fluoroscopy
or ultrasonography. The pressure within the kidney
can be measured via a manometer connected to the
tubing, and a collection of urine for cytologic examination can be obtained during the procedure.
Reference Values
Normal outline of the urinary collecting system;
normal size and position of the ureters and
urinary bladder
INTERFERING FACTORS

Inability of client to remain still and maintain
position required for the procedure

CHAPTER 17—Radiologic

Failure to restrict foods or to drink fluids to dilate
the collecting system before the procedure
Metal objects within the x-ray field
INDICATIONS FOR ANTEGRADE PYELOGRAPHY

Evaluating the kidneys and ureters for obstruction
and degree of resulting dilatation
Detecting the cause of an obstruction such as
tumor, stone, or stricture
Determining the patency of the upper collecting
system when an obstruction prevents a retrograde
ureteropyelography from being performed or
when it has been unsuccessfully performed
Examining the upper collecting system to evaluate
an obstruction in a ureter when a cystoscopy is
contraindicated
Determining ureteral obstruction after a surgical
urinary diversion procedure or other ureteral
surgery
Evaluating hydronephrosis in children, caused by
ureteral anomaly or abnormality at the junction
of the ureter with the kidney
Placement of a nephrostomy tube for drainage
Measuring intrarenal pressure for increases indicating obstruction
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Inability of client to cooperate during the procedure
Allergy to iodine or history of allergy to contrast
medium
Obesity that prevents needle placement
Uncontrolled coagulopathy with prolonged clotting time, PT, PTT, and abnormal coagulation
factors panel
Nursing Alert

Assess and observe for accidental puncture of
adjacent organs, leading to pneumothorax or
extravasation of the contrast medium into the
surrounding area.
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Percutaneous
Transhepatic Cholangiography” section.
Inform the client that the procedure takes 1 hour.
The history and assessment should include the
results of blood urea nitrogen (BUN) and creatinine.
Advise the client of fluid intake before the study,
according to agency and physician preference.

Studies

425

THE PROCEDURE

The client is placed on the x-ray table in a prone
position and the injection site is exposed and
draped. The skin is cleansed with an antiseptic solution and injected with a local anesthetic, usually
lidocaine. The client is informed that some pain is
experienced when the local anesthetic is injected.
The client is requested to hold the breath. While
fluoroscopy or ultrasonography is being used, a 21gauge percutaneous needle is inserted at the level of
the second lumbar vertebra below the ribs in the
direction of the kidney. A smaller needle with a stylet
is then advanced through the needle and into the
renal midpelvis. Flexible tubing is attached to the
needle and a syringe is attached to the tubing to
aspirate urine from the kidney.95 A urine specimen
can be obtained and a manometer can be connected
to the tubing at this time to measure intrarenal pressure as an indication of obstruction. The dye is then
injected via the needle after the urine has been aspirated to prevent overdistention of the pelvis. Inform
the client to report any nausea, flushing, or sweating
when the dye is injected. Several views are taken,
including PA, AP, and oblique. After the injection of
the dye, which fills the collecting system, fluoroscopy
can reveal ureteral peristalsis and the point of
obstruction as the contrast material outlines the
organs. If a nephrostomy tube is to be inserted, it is
inserted at this time to treat renal dilatation caused
by intrarenal reflux that leads to nephrosis.96 The
tube is self-retaining and provides continuous
drainage of the renal pelvis. The needle is then
removed and a sterile dressing applied over the
puncture site or nephrostomy tube and taped in
place.
NURSING CARE AFTER THE PROCEDURE

Place the client at rest in a position of comfort,
preferably avoiding the side on which the injection was performed.
Monitor vital signs and compare with baseline
readings until the client is stable, paying special
attention to indications of bleeding.
Assess the site for bleeding and leakage of urine.
Monitor intake and output (I&O) for the first 24
hours for hematuria.
Inform the client to increase fluid intake to 2000
to 3000 mL per day, unless contraindicated.
If a nephrostomy tube is in place, monitor for
patency, gravity drainage, and drainage characteristics.
Administer a mild analgesic for any discomfort
and antibiotic therapy, if ordered, to prevent
infection.

426

SECTION II—Diagnostic

Tests and Procedures

Reaction to iodinated contrast medium: Note
and report anxiety, warmth or flushing, itching,
urticaria, sweating, nausea, or vomiting.
Administer ordered antihistamines or steroids.
Initiate resuscitation procedure as needed.
Hemorrhage: Note and report flank pain,
hypotension, or rapid pulse. Administer blood
transfusion, if ordered. Prepare for surgery to
correct problem.
Septicemia: Note and report elevated temperature, chills, and vital sign changes. Administer
ordered antipyretic and antibiotic therapy.
Puncture of organs: Note and report respiratory
changes for possible pneumothorax; note abdominal or flank pain. Administer ordered medications. Assist with chest tube insertion. Prepare for
surgery to correct organ damage.

RETROGRADE URETHROGRAPHY
A retrograde urethrogram allows visualization of the
male urethral membranous, bulbar, and penile areas
or of the female urethra, if diverticula are suspected.
It is most commonly performed on men postoperatively to evaluate urethral repair and to assist in the
diagnosis of urethral abnormalities and congenital
anomalies. For this study, the iodinated contrast
medium is instilled into a catheter and inserted into
the meatus. Films are made while a portion is
injected and again while the remaining portion is
instilled. A combination of films and fluoroscopy
can be performed to visualize possible trauma to the
urethra.97
Reference Values
Normal size and shape of the urethra; no deviations or diverticula, fistula, stones, or strictures
INDICATIONS FOR RETROGRADE
URETHROGRAPHY

Evaluation of the urethra in male children for
congenital anomalies such as hypospadias, inappropriate passages
Detection of stones, urethral stricture, or meatal
stenosis causing obstruction
Detection of lesions, lacerations, diverticula, or
fistula of the urethra
Evaluation of the male urethra for obstruction at
the neck of the bladder caused by hypertrophy of
the prostate gland
Preparation for balloon dilatation of the prostatic
urethra
Suspected urethral diverticula in females

Determination of the status of the male urethra
after surgical correction or repair
CONTRAINDICATIONS

Inability of client to assume and maintain the
position to perform the procedure
Urinary tract infection (UTI) unless the study is
performed with caution
Extensive injury or trauma to the urethra
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That there are no food or fluid restrictions
That a sedative can be administered before the
study to promote relaxation
That a catheter will be inserted to administer the
contrast medium and that moderate discomfort
will be experienced when the material is injected
Prepare for the procedure:
Obtain a history to ascertain the date of the last
menstrual period and the possibility of pregnancy, allergy to iodine, known or suspected
urinary disorders, and results of associated tests
and procedures.
Administer a sedative or analgesic, or both, such
as meperidine IM or subcutaneously (SC) 30
minutes before the study to promote comfort and
relaxation.
Have client void.
THE PROCEDURE

The client is placed on the x-ray table in a supine
position, and an AP film is taken to view for stones
in the bladder or urethra. The client is draped for
privacy with the genitalia exposed. The meatus is
cleansed with an antiseptic solution. After the
catheter is filled with the contrast medium, the tip is
moistened with water and inserted until the balloon
part of the catheter is within the urethra just past the
meatus. The balloon is then inflated with water and
the client placed in a right oblique posterior position. The right leg is flexed at a right angle and, if the
client is male, the penis is positioned on the right
thigh with the left leg straight. Contrast material is
injected into the catheter and a spot film is taken.
Additional films are taken while the remaining
material is injected into the catheter. If the client is
female, a double balloon catheter is used to anchor
the catheter above and below the meatus.
Fluoroscopic examination can be performed to
reveal trauma to the urethra. On completion of the
films, the water is removed from the balloon and the
catheter is removed.

CHAPTER 17—Radiologic

NURSING CARE AFTER THE PROCEDURE

Monitor vital signs and compare with baselines
until stable.
Monitor I&O for at least 24 hours, with special
attention given to the first voiding and urine characteristics.
Assess for suprapubic pain or absence of urination. Inform the client to increase fluid intake to
promote hydration, to remove the dye from the
urethra, and to prevent dysuria.

Studies

427

abnormalities affecting the insertion of the
catheter into the bladder
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Retrograde
Urethrography” section.
Inform the client that clear liquids are allowed,
depending on agency and physician preference.
Insert a Foley catheter, if one has been ordered.
THE PROCEDURE

RETROGRADE CYSTOGRAPHY
A retrograde cystogram is performed to visualize
and evaluate possible rupture and pathology of the
urinary bladder. Air or an iodinated contrast
medium is instilled into the bladder via a catheter,
the catheter is clamped, and several views are
taken, depending on the extent of the examination
needed and the client’s condition. Filming the bladder and urethra after the catheter is unclamped
and during emptying is known as a voiding
cystourethrogram.98
Reference Values
Normal size, shape, and structure of the urinary
bladder; no tumor, fistula, diverticula, or perforation of the bladder
INTERFERING FACTORS

Barium, feces, or gas in the LGI tract
INDICATIONS FOR RETROGRADE CYSTOGRAPHY

Examination of the bladder when excretory
urography has not provided adequate visualization of the bladder or when cystoscopy is
contraindicated
Suspected neurogenic bladder, that is, hypotonic
or hypertonic bladder
Suspected primary pathology of the bladder
including tumor, fistula, or diverticula99
Abnormal bladder function and filling defects
caused by vesicoureteral reflux and revealed by
backflow of dye into the ureters from the bladder
Determination of rupture or perforated bladder
revealed by extravasation of the contrast medium
Persistent, recurrent UTIs in children
CONTRAINDICATIONS

Acute UTI
Injury to the bladder or urethra
Obstruction of the urethra or other urethral

The client is placed on the x-ray table in a supine
position and an abdominal flat plate (KUB) film is
taken to determine whether stones or calcifications
are present in the urinary tract or whether barium or
gas is present in the gastrointestinal tract. These
substances can interfere with visualization. The
client is draped with the genitalia exposed. A Foley
catheter is inserted, and urine is drained until the
bladder is completely empty. About 300 mL (less for
an infant or child) of the contrast medium is
instilled into the bladder via the catheter by gravity
or a little pressure. Instruct the client to report any
nausea, flushing, or sweating when the dye is
injected. The catheter is then clamped and an AP
view is taken. Additional oblique and lateral views
are taken after position changes of the client. A
protective shield is placed over the male testes to
prevent irradiation; a shield over a woman’s
abdomen would interfere with visualization of the
bladder.100 A PA view can also be taken if the client
is able to assume the jack-knife position. To improve
visualization, it is possible for air to be injected into
the bladder after removal of the dye. This procedure
is known as a double-contrast study. After the filming, the dye is drained from the bladder and the
catheter is removed if the client is able to void.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those described in the “Retrograde
Urethrography” section.
Monitor urinary characteristics and pattern and
instruct the client to report persistent hematuria
caused by the trauma of the procedure or UTI.
If the catheter is left in place, attach to a sterile
closed drainage system.
Reaction to iodinated contrast medium:
Note and report anxiety, warmth, flushing, itching, urticaria, sweating, nausea, or vomiting.
Administer ordered antihistamines or steroids.
Initiate resuscitation procedure as needed.
UTI: Note and report dysuria, urgency, frequency,
or cloudy and foul-smelling urine. Administer

428

SECTION II—Diagnostic

Tests and Procedures

ordered antimicrobial therapy. Obtain urine specimen for culture and sensitivity (C&S).

RETROGRADE URETEROPYELOGRAPHY
The retrograde ureteropyelogram, also known as a
retrograde pyelogram, involves the x-ray filming of
the ureters and the renal collecting system. It is used
when an IVP does not provide satisfactory visualization of the kidneys or when previous IVP findings
must be confirmed.101 Because the dye is not readily
absorbed by the ureters, this study is preferred in
clients who are allergic to an iodinated contrast
medium when administered IV, as in the IVP. The
contrast medium diatrizoate sodium is injected via
ureteral catheters inserted by cystoscopy. Various
views are filmed with the catheters in place and
during and after their removal.
Reference Values
Normal size and shape of the ureters and
kidneys; no stones, tumor, strictures, or other
abnormalities causing actual or risk of obstruction
INTERFERING FACTORS

Barium, feces, or gas in the gastrointestinal tract
INDICATIONS FOR RETROGRADE
URETEROPYELOGRAPHY

Determining presence and location of a stone
in the ureter or kidney when this condition
has not been established with other diagnostic
studies
Diagnosing renal conditions such as impaired
renal function or decreased kidney perfusion
resulting from vascular disorders or congenital
anomaly that could not be identified by excretory
urography (IVP)
Determining tumors, strictures, scarring, and
compression against the ureter with displacement, causing partial or complete obstruction102
Determining whether kidney disease, especially in
cases with one kidney involved, is caused by
ureteral obstruction
CONTRAINDICATIONS

Allergy to the contrast medium (Very little is
absorbed through the mucous membranes of the
ureter, however.)
Pregnancy, unless benefits of performing
the procedure greatly outweigh the risks to the
fetus

NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are generally the same as those described in the “Retrograde
Urethrography” section.
Inform the client that the procedure takes 60 to 90
minutes and involves the insertion of an instrument into the bladder, which causes some
discomfort.
Foods and fluid are restricted for 8 to 12 hours
before the study if general anesthesia is used, but
a clear liquid diet can be given the morning of the
study if a local anesthetic is used.
A laxative, suppository, or enema, or a combination of these measures, should be administered
the evening before the study.
Initiate an IV line and administer IM or SC
meperidine for relaxation and comfort and
atropine sulfate to reduce secretions 1 hour before
the study, if ordered.
Kidney function laboratory tests (BUN, creatinine) should be assessed for levels indicating renal
impairment.
THE PROCEDURE

The client is placed on the x-ray table in the lithotomy position with the legs and feet in stirrups and
a drape for privacy concerns. General anesthesia is
administered or local anesthetic is inserted into the
urethra in the form of a jelly. Oral or IV medications
to promote relaxation and comfort can be administered with the local anesthetic. A cystoscope is
inserted into the bladder and the organ visualized to
observe the size, shape, and presence of abnormalities such as tumor, lesions, or stones. This step is
followed by the insertion of opaque catheters
through the cystoscope and into the ureters up to the
level of the pelves of the kidneys. Placement is verified by x-ray of the opaque catheters. The urine is
drained from the kidneys and a small amount of the
dye is injected through the ureteral catheters.
Instruct the client to report any nausea, flushing, or
sweating after the dye is injected. An AP film is taken
and an additional amount of dye is injected and
lateral and oblique views taken. Films of the ureters
are taken while the catheters are withdrawn and
small amounts of dye are injected. In some instances,
delayed filming is performed 10 to 15 minutes after
complete removal of the catheters to determine
urinary retention.103 At the conclusion, the catheters
can be left in place and allowed to drain to ensure the
return of urinary flow. Otherwise, they are removed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the

CHAPTER 17—Radiologic

same as those described in the “Retrograde
Urethrography” section.
If the catheters are left in place, connect to a sterile closed drainage system and establish flow by
gravity.
Anchor and protect the catheters to prevent backflow and dislodgement.
Assess the catheters for patency and drainage
characteristics (pink-tinged color is not unusual
because of the introduction of instrumentation)
as well as the first urination if catheters are not in
place.
Inform the client to report absence of urination,
bright red blood, or clots in the urine.
UTI: Note and report dysuria; urgency;
frequency; or cloudy, foul-smelling urine.
Administer ordered antimicrobial therapy. Obtain
urine specimen for C&S.

INTRAVENOUS PYELOGRAM
The intravenous pyelogram (IVP), also known as the
excretory urogram (EUG), is most frequently
performed to evaluate the calyces and pelves of the
kidneys, ureters, and urinary bladder when abnormalities of these organs are suspected.104 An abdominal flat plate (KUB) film is taken, an iodinated
contrast medium such as diatrizoate sodium or
diatrizoate meglumine is injected, and then serial
filming is performed. The study can include a
nephrogram because the material concentrates in
the renal tubules. Serial nephrotomography can also
be performed to delineate kidneys for mass thickness without interference from surrounding tissues.
Reference Values
Normal structure, size, and shape of the kidneys,
ureters, and bladder; no tumor, mucosal abnormalities, or impaired renal function

INTERFERING FACTORS

Barium, feces, or gas in the gastrointestinal tract
Impaired renal function causing inability of the
kidneys to excrete the dye
INDICATIONS FOR INTRAVENOUS PYELOGRAM

Suspected diseases or abnormalities of the
kidneys, ureters, or bladder as a result of structural defects or tumors
Determination of tumors, stones, or strictures
causing partial or complete obstruction105
Determination of glomerular disorders revealed
by the rate of dye excretion

Studies

429

Diagnosis of renal artery obstruction as shown by
the failure of the dye to reach a kidney and the
resultant inability to visualize the urinary system
Determination of changes in the size, shape, and
position of the kidneys, caused by pathology
Determination of the results of trauma on the
urinary organs, such as hematoma or lacerations
Diagnosis of congenital abnormalities such as
absence of one kidney, abnormal connection of
the two kidneys in the shape of a horseshoe,
displaced kidneys in the abdomen, or double
ureters106
Suspected urinary residual in the bladder
Determination of the cause of renal hypertrophy,
such as hydronephrosis or polycystic kidney
disease
CONTRAINDICATIONS

Allergy to iodine or iodinated contrast media
(Antihistamine and steroid therapy should be
administered in this case.)
Actual or potential dehydration, especially in children or elderly clients
Abnormal renal function with increases in creatinine and BUN level greater than 40 mg/dL
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Retrograde
Ureteropyelography” section.
Assess laboratory tests and report BUN levels of
greater than 40 mg/dL.
Provide bowel preparation according to institution and physician requirements.
Although food is restricted, allow clear fluids the
morning of the study.
THE PROCEDURE

The client is placed on the x-ray table in a supine
position and draped for privacy. An abdominal flat
plate (KUB) film is taken to determine the presence
of stones, feces, gas, or barium, which can interfere
with visualization. An IV line is initiated and the dye
is injected; the amount of dye depends on the age of
the client. Have the client report any nausea, flushing, or sweating after injection of the dye. While the
client remains in the same position, films are taken at
intervals of 1, 5, 10, 15, 20, and 30 minutes or as long
as it takes the contrast medium to reach the bladder.
Within 5 minutes the material concentrates in the
renal tubules and a nephrogram can be obtained.107
After the filming, the client is requested to void and
another film is taken to visualize the bladder and
determine whether residual urine is present. If filming of the ureters is desired, a rubber bladder is

430

SECTION II—Diagnostic

Tests and Procedures

placed around the abdomen and inflated to trap the
contrast medium in the upper ureters, and an x-ray
is taken. The tube is then deflated and the filming of
the lower ureters and bladder continues.
Nephrotomography can be performed as an
adjunct to the IVP for better visualization of tumors
or occupying lesions. It requires additional films that
delineate layers or slices of the kidneys for mass
thickness without interference in the views from the
surrounding tissue. Serial tomograms are made 10
minutes after the injection of the contrast medium
as the x-ray tube and film cassette move in opposite
directions.108,109 This study can be made without
IVP after the same procedure.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those described in the “Retrograde
Urethrography” section.
Continue IV fluids or provide oral fluids to
promote hydration.
Monitor IV site for hematoma or infiltration, and
discontinue or change site, if appropriate.
Reaction to iodinated contrast medium: Note
and report anxiety, warmth, flushing, itching,
urticaria, sweating, nausea, or vomiting.
Administer ordered antihistamines or steroids.
Initiate resuscitation procedure as needed.
Renal failure: Note and report anuria, oliguria,
increased BUN and creatinine, and fluid intake.
Initiate ordered IV and administer fluids and
medications. Prepare for dialysis, if appropriate.

VOIDING CYSTOURETHROGRAPHY
The voiding cystourethrogram is performed to visualize the filling and emptying of the urinary bladder.
A catheter is inserted into the bladder and an iodinated contrast medium is instilled. Filming is
performed to view the filling process and then
during voiding to demonstrate the emptying
process. The study can be performed in conjunction
with retrograde cystography or as a single procedure.
Reference Values
Normal size, shape, and structure of the urinary
bladder; no abnormality in bladder function or
emptying

INDICATIONS FOR VOIDING
CYSTOURETHROGRAPHY

Suspected or known neurogenic bladder (hypotonic or hypertonic bladder) causing incontinence
Determination of vesicoureteral reflux in adults
and children (Corrective surgery may be
required.)
Determination of strictures, urethral stenosis,
diverticula, ureteroceles, prostatic enlargement
that interferes with bladder function
Evaluation of abnormal bladder function to
determine whether surgery is indicated
Diagnosis of the cause of chronic UTIs
Identification of congenital anomalies in infants
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Acute urethral or bladder infection
Injury to the bladder or urethra
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Retrograde
Urethrography” section.
THE PROCEDURE

The client is placed on the x-ray table in a supine
position and draped for privacy. A Foley catheter is
inserted, and the contrast medium is injected into
the bladder via the catheter. The catheter can then be
clamped and films taken in the supine, lateral, and
oblique positions. The catheter is then unclamped
and removed. The client is requested to void, and
films are taken of the bladder and urethra during
voiding. If the client has difficulty voiding, a standing position can be assumed while the films are
taken. When this procedure is performed on children, they are anesthetized and urine is expressed
from the bladder.110 A protective shield is placed
over the male testes to prevent irradiation. Female
clients cannot be shielded without interfering with
visualization of the bladder.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those described in the “Retrograde
Urethrography” section.

INTERFERING FACTORS

Barium, feces, or gas in the LGI tract
Trauma or embarrassment that prevents voiding
when requested to do so

SIALOGRAPHY
The sialogram involves the x-ray examination of the
salivary ducts, that is, sublingual, submaxillary,

CHAPTER 17—Radiologic

submandibular, and parotid ducts. Filming follows
the injection of an iodinated contrast medium into
the duct to be studied. Views are taken with the
client in various positions to identify pathology in
the ducts.
Reference Values
Normal function of salivary glands and ducts;
no stones, strictures, tumors, or other abnormalities
INTERFERING FACTORS

Stone in a duct that prevents the dye from
entering
INDICATIONS FOR SIALOGRAPHY

Evaluation of persistent pain and edema in the
salivary gland areas111
Suspected stones, tumors, or strictures that
obstruct the salivary ducts
Suspected inflammation of the salivary glands
CONTRAINDICATIONS

Studies

431

and report feeling of warmth, flushing, urticaria,
itching, nausea, or vomiting. Administer ordered
antihistamine.

ARTHROGRAPHY
The arthrogram involves a series of x-rays to examine the joint as well as soft tissues surrounding the
joint, including the meniscus, cartilage, ligaments,
and structures of the joint capsule (rotator cuff,
subacromial bursa).113 The procedure usually
follows chronic, persistent, and unexplained pain in
a joint. The knee and shoulder are the most
common sites for the procedure, but other joints
(hip, wrist, ankle) can also be examined by arthrography. Various views are taken of a joint site after it
has been anesthetized and injected with a contrast
medium.
Reference Values
Normal joint structures including articular
cartilage, bursae, meniscus, ligaments, and joint
space; no fracture, tears, disruptions, or lesions
of the joint

Mouth infection and inflammatory conditions
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plain x-ray procedure (see section
under “Skull Films” at beginning of chapter).
Client should brush teeth and rinse mouth with
mouthwash.
THE PROCEDURE

The client is placed on the x-ray table in a supine
position, and a plain x-ray is taken to determine
whether a stone is present in the duct. A catheter
is inserted into the duct and the dye injected
into the catheter. Various views of the duct are
filmed. The client is then given a sour drink to
encourage salivation. Additional views are taken to
film ductal drainage and evaluate function and
patency.112
NURSING CARE AFTER THE PROCEDURE

Monitor vital signs and compare with baseline
readings.
Encourage fluid intake to assist in elimination of
the dye.
Monitor the injection site for pain and swelling,
and administer a mild analgesic if ordered.
Provide mouth care for comfort and for reduction
of the possibility of infection at the injection site.
Reaction to iodinated contrast medium: Note

INTERFERING FACTORS

Inability of client to cooperate in the procedure
Synovial fluid affecting the concentration of the
contrast medium
INDICATIONS FOR ARTHROGRAPHY

Determining the cause of persistent, unexplained
knee or shoulder pain
Evaluating and differentiating between acute and
chronic conditions of the knee or shoulder
Determining traumatic ligament disorders such
as tears and lacerations
Evaluating meniscal tears, lacerations, fractures,
and extrameniscal lesions such as osteochondritis
or chondromalacia114
Evaluating chronic shoulder dislocations and
resulting joint damage
Determining abnormalities of the synovial
membrane, such as synovitis, tumors, or cysts
Evaluating damage to the cartilage and other joint
structures caused by arthritis
Detecting shoulder abnormalities such as rotator
cuff tear, capsule derangement, capsulitis, or
capsule rupture
Diagnosing conditions of the bursa such as bursitis or tears
Performing surgical procedures on the joint to
correct minor conditions

432

SECTION II—Diagnostic

Tests and Procedures

CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Infectious process of the joint
Acute exacerbation of arthritis
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Percutaneous
Transhepatic Cholangiography” section or for any
study involving the insertion of the contrast
medium directly into the examination site.
The study takes 30 to 45 minutes, fluid and food
are not restricted, and no sedation is administered
before the procedure.
The procedure is performed under a local anesthetic injected into the examination site.
THE PROCEDURE

The client is placed on the x-ray table in a supine
position with the shoulder, knee, or other joint
exposed. The site is cleansed with an antiseptic solution and draped for a sterile procedure. A local injection of lidocaine is given to anesthetize the skin. A
needle is inserted into the joint space and synovial
fluid is aspirated. The fluid can be sent to the laboratory for analysis. The syringe is disconnected and
another syringe containing a soluble dye is attached
after needle placement has been confirmed by fluoroscopic examination. Gas and water as well as the
iodinated dye can also be used as a contrast agent.
The dye is instilled and the joint is manipulated as in
a range-of-motion exercise or the client is requested
to walk to distribute the dye throughout the joint
space. The client is informed that discomfort is
experienced when the dye is injected and movement
of the joint takes place. Films are taken with the joint
manipulated into several positions. After the x-ray
filming, the knee or other joint is bandaged and
wrapped with an elastic bandage.
NURSING CARE AFTER THE PROCEDURE

Assist the client from the x-ray table and place the
joint at rest for at least 12 hours.
Monitor vital signs and compare with baseline
readings.
Apply ice to the site and administer an ordered
mild analgesic.
Inform the client that a crepitant noise in the joint
can last for 1 to 2 days, and instruct to report pain
and swelling that does not subside.
Advise the client to minimize weight bearing, to
avoid strenuous activities if a knee joint was
examined, and to maintain the elastic bandage

over the joint until the physician recommends its
removal.
Reaction to iodinated contrast medium: Note
and report warmth, flushing, itching, nausea, or
changes in breathing pattern. Administer ordered
antihistamines and steroids. Have resuscitation
equipment on hand.

BRONCHOGRAPHY
The bronchogram involves x-ray examination to
visualize the tracheobronchial tree after injection of
an iodinated oil contrast medium via a catheter
inserted into the trachea and bronchi.115 The lining
of the tracheobronchial tree becomes coated and
films are then taken with the client in various positions. Bronchography has been generally replaced as
a diagnostic procedure by bronchoscopy, a study
that provides direct visualization of the area.
Bronchography can be performed to assist with or in
conjunction with bronchoscopy or chest tomography. The major advantage of bronchography is
provision of permanent films for future reference.
Reference Values
Normal structure of the tracheobronchial
airways; no bronchiectasis, airway obstruction,
tumors, cysts, or congenital abnormalities
INTERFERING FACTORS

Excessive secretions in the tracheobronchial space
Coughing that prevents coating of the airways
with the contrast medium
INDICATIONS FOR BRONCHOGRAPHY

Detecting obstructions in the bronchi caused by
tumor, cyst, or foreign object
Determining the cause of persistent hemoptysis
and recurring pneumonia
Diagnosing bronchiectasis, tumors, cysts, or cavities in the pulmonary system
Evaluating the tracheobronchial tree before anticipated surgery
Placing bronchoscope for direct visualization of
the airways when done in conjunction with bronchoscopy
Diagnosing hyaline membrane disease and transient tachypnea in infants
Detecting congenital malformation of the
tracheobronchial tree in infants116
Providing a permanent record of films that
outline pathology of the tracheobronchial tree

CHAPTER 17—Radiologic

CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Respiratory infection
Excessive coughing and mucus production
Condition causing respiratory insufficiency or
possible failure
Nursing Alert

Special precautions should be taken in clients
with chronic obstructive pulmonary disease
(COPD) while contrast medium is injected,
because the medium can exacerbate laryngeal
or bronchial spasms or dyspnea, or both.117
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for bronchoscopy (see section titled
“Bronchoscopy” in Chapter 16).
Inform the client that postural drainage or other
breathing treatments are performed 1 to 3 days
before the study to remove secretions.118
An expectorant can be administered if a cough is
present; oral care can be recommended, with
teeth brushing and mouthwash, to promote
cleanliness and prevent introduction of microorganisms into the airways and lungs.
Take a history that includes last menstrual period
date to determine possibility of pregnancy; allergy
to iodine, iodinated contrast medium, or local
anesthetic; or known or suspected pulmonary
conditions.
Request that the client remove all jewelry,
dentures, and glasses.
Provide pulmonary toilet and mouth care the
evening and morning before the study.
Administer IM or SC diazepam for sedation and
relaxation, atropine sulfate for reduction of secretions and gag reflex, and expectorant 30 minutes
before the procedure for productive cough, if
present.
THE PROCEDURE

The client is placed on the x-ray table in a sitting
position. The throat and nose are sprayed with a
local anesthetic and the client placed in a supine
position. The client is requested to avoid swallowing
the anesthetic. A child or client who is unable to
remain still during the procedure is given a general
anesthetic. A catheter or a bronchoscope is inserted
into the trachea, and an anesthetic is injected into
the airway to include the pharynx, larynx, and

Studies

433

bronchi. Administration of the anesthetic is
followed by injection of the iodinated contrast
medium via the catheter or scope. At this time the
client is instructed to increase breathing to keep
from coughing up the contrast medium.119 The
client is placed in different positions to spread the
contrast medium into the areas of the bronchi to be
viewed. Films are taken in these positions.
NURSING CARE AFTER THE PROCEDURE

Perform postural drainage techniques to remove
the contrast medium from the tracheobronchial
tree. Encourage coughing to assist in this removal.
When the gag reflex returns, resume food and
fluid intake (usually in 2 to 4 hours).
Monitor for laryngospasm or bronchospasm and
respiratory changes that result from those complications.
After the gag reflex returns, administer throat
lozenges and warm fluid gargle for throat soreness
or irritation caused by the catheter, taking care to
prevent aspiration.
Provide for follow-up x-rays to ensure that all the
contrast medium has been removed to prevent
pneumonia.
Reaction to iodinated contrast medium: Note
and report warmth, flushing, itching, and nausea.
Administer ordered antihistamine and steroids.
Have resuscitation equipment on hand.
Pneumonia: Note and report dyspnea, rales,
rhonchi, temperature elevation, change in sputum
color to yellowish green. Administer ordered
antibiotic and oxygen therapy.

HYSTEROSALPINGOGRAPHY
The hysterosalpingogram involves the visualization
of the uterine cavity and the fallopian tubes after the
injection of a water-soluble or oil-based iodinated
contrast medium via a cannula inserted into the
cervix. The flow of the material is viewed fluoroscopically and x-ray films are taken.120 The study is
performed to identify abnormalities of the female
reproductive organs.
Reference Values
Normal uterus and fallopian tube structure and
patency; no tumors, adhesions, fistula, or
foreign bodies
INTERFERING FACTORS

Feces or gas in the LGI tract
Spasms of the fallopian tubes that can appear as a
stricture of the tubes

434

SECTION II—Diagnostic

Tests and Procedures

Excessive traction on the tubes that can appear as
normal when the traction displaces adhesions121
INDICATIONS FOR HYSTEROSALPINGOGRAPHY

Evaluating tubal patency that cannot be determined by ultrasonography
Detecting foreign bodies such as a displaced or
dislodged intrauterine device (IUD) or tubal
pregnancy
Determining tubal obstruction caused by tumors,
scarring, adhesions, kinking, or mucous plugs
Correcting suspected adhesions, mucous plugs, or
kinking by therapeutic clearing of these obstructive conditions as an adjunct to fertility studies
Confirming possible fertility difficulties
Diagnosing uterine tumor, fistula, trauma, or
congenital abnormalities
Evaluating tubal ligation or tubal reanastomosis
procedures
Determining the cause of repeated spontaneous
abortions
CONTRAINDICATIONS

Pregnancy or suspected pregnancy
Infection of the cervix, vagina, endometrium, or
fallopian tubes
Pelvic inflammatory disease
Vaginal bleeding or menstruation
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Retrograde
Urethrography” section.
The history should include assurance of completion of a menstrual period 10 days before the
study.
Depending on agency policy and physician preference, administer a laxative the night before and an
enema, suppository, and douche before the study.
Administer an ordered sedative such as diazepam
to reduce anxiety, promote relaxation, and
prevent spasms of the fallopian tubes.
THE PROCEDURE

The client is placed on the x-ray table in the lithotomy position with the legs and feet supported by
stirrups and draped for privacy. An abdominal flat
plate (KUB) film is taken to ensure that nothing
exists in the lower bowel to interfere with visualization. A vaginal speculum is inserted and the cervix is
cleansed with an antiseptic. A catheter is then
inserted into the cervix and, while it is being viewed
by fluoroscopy, the dye is injected into the uterus
and fallopian tubes until they are filled. The client is
informed that some lower abdominal cramping or

shoulder pain will be experienced as the dye reaches
the peritoneal cavity. The client is also requested to
report any nausea, flushing, or sweating after the dye
is injected. X-ray films are taken and the client’s
position is changed to obtain an oblique view. At
completion of the filming, the catheter is removed.
NURSING CARE AFTER THE PROCEDURE

Monitor vital signs and compare with baseline
readings.
Provide a pad for vaginal discharge and monitor
the drainage for bleeding.
Inform the client that some bloody discharge can
be expected for 2 days after the study.
Assess for cramping and dizziness, and remind
the client to report any delayed reaction to the dye
or possible infection.
Reaction to iodinated contrast medium: Note
and report anxiety, warmth, flushing, urticaria,
itching, nausea, and vomiting. Administer
ordered antihistamines and steroids. Have resuscitation equipment on hand.
Infection: Note and report temperature, abdominal pain, malaise, and vaginal discharge characteristics. Administer ordered analgesic and antibiotic
therapy.
Perforation: Note and report abdominal pain,
profuse vaginal bleeding, and signs and symptoms
of peritonitis. Administer ordered antibiotic therapy. Prepare client for possible surgical repair of
uterus.

MYELOGRAPHY
The myelogram allows visualization of the spinal
subarachnoid space or the spinal canal to determine
abnormalities. A contrast medium is injected into
the spinal canal via a lumbar puncture. Fluoroscopy
provides a view of the flow toward the head as the
table is tilted. X-rays are taken at the same time. A
cisternal puncture can be performed if a lumbar
puncture is contraindicated.122
Reference Values
Normal structure of the subarachnoid spaces of
the spinal column; no spinal abnormalities or
obstructions
INTERFERING FACTORS

Inability of client to remain still during the procedure
Spinal curvatures or other abnormalities that
prevent lumbar or cervical puncture for dye injection

CHAPTER 17—Radiologic

Inaccurate needle placement in the spinal column
Metal objects within the field
INDICATIONS FOR MYELOGRAPHY

Suspected congenital abnormalities or injuries
that place pressure on the spinal posterior fossa of
the skull or on the nerve roots123
Detection of lesions of the spinal column such as
cord or meningeal tumors, cysts, or ruptured
intervertebral disks
Detection of changes in bone structure of the
spinal column caused by arthritis and ankylosing
spondylosis
Determination of the cause of chronic, unrelieved
back pain and pain that radiates down the leg with
associated footdrop
Diagnosis of conditions affecting the subarachnoid space or spinal cord in the presence of
neurological signs and symptoms that suggest an
injury or loss of neuromuscular function
Confirmation of diagnosis or pathology before
anticipated or scheduled surgical procedure
CONTRAINDICATIONS

Pregnancy, unless benefits of performing the
procedure greatly outweigh the risks to the fetus
Known allergy to iodine or iodinated contrast
media
Suspected or confirmed increase in intracranial
pressure
Infection at the puncture site
Chronic neurological disease such as multiple
sclerosis
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Retrograde
Urethrography” section.
The history should include known or suspected
neuromuscular disorders that could be exacerbated or worsened by this procedure and medication regimens that include phenothiazines to treat
seizure disorders.
Food and fluids are restricted for 8 to 12 hours
before the study.
Administer a laxative or enema before the study to
clear the bowel of feces or gas.
Shave the puncture area if it is necessary.
Administer an IM or SC sedative such as
diazepam to promote relaxation and an anticholinergic such as atropine sulfate to reduce
secretions.
Advise the client that the site will be anesthetized
by local injection and a lumbar puncture

Studies

435

performed to inject the dye into the spinal
column to facilitate visualization.
THE PROCEDURE

The client is placed at the edge of a tilted x-ray table
in a side-lying position. The lumbar or cervical
puncture site, depending on the suspected pathology, is cleansed with an antiseptic solution and
draped to provide a sterile field. The site is then
injected with a local anesthetic. The client is
requested to flex the knees and bend the head downward if a lumbar puncture is performed. If a lumbar
puncture is contraindicated, a cisternal puncture is
performed. Placement of the needle is verified by
fluoroscopy, and some cerebrospinal fluid (CSF) can
be collected for laboratory examination. The client is
then placed in a prone position with straps and
shoulder and foot braces to prevent movement or
falling. Contrast medium in the same amount as the
removed CSF, usually 15 mL, is injected via the
needle in the spinal canal. The client is informed that
a burning sensation will be experienced when the
dye is injected. The client is asked to report a warm,
flushed feeling or unusual pain during injection of
the dye. An iodinated water-soluble contrast
medium (metrizoate sodium) is most commonly
used, but an oil-based medium or air contrast can
also be injected. Air contrast studies are performed
to avoid side effects from other media.124 The table
is tilted to distribute the flow of dye and fluoroscopy
is used to follow the dye in a cephalad direction.125
Spot films are taken and obstructions, if present, are
identified. Various views can also be taken with position changes. After conclusion of the filming, the oilbased medium, if used, is aspirated and the needle
removed. The site is bandaged and taped in place.
CT scanning can be performed during or after the
myelogram to identify lesions that are difficult to
diagnose. The specimen, if obtained, is properly
labeled and sent to the laboratory for examination.
NURSING CARE AFTER THE PROCEDURE

Inform the client that a headache can occur.
Elevate the head of the bed to a semi-Fowler’s
position (45 degrees) if a water-soluble medium
was used.
Place the client’s head in a position lower than the
body if air was used.
Keep client in a prone position for 2 hours,
followed by a supine position for 2 to 4 hours if an
oil-contrast medium was used. If the oil was not
withdrawn, elevate the head to prevent the oil
from reaching the brain.
Monitor vital signs and compare with baseline
readings.

436

SECTION II—Diagnostic

Tests and Procedures

Encourage fluid intake to assist in the removal of
the dye and replacement of CSF; monitor voiding
pattern.
Perform neurological checks for presence of
headache, photophobia, stiff neck, or seizure
activity caused by meningeal irritation.
If nausea or vomiting is present, administer an
ordered antiemetic other than a phenothiazine.
Reaction to iodinated contrast medium: Note
and report warmth, flushing, nausea, vomiting, or
itching. Administer ordered antihistamine and
steroids. Have resuscitation equipment on hand.
Meningitis: Note and report severe headache, stiff
neck, irritability, seizure activity, or fever.
Administer ordered medications. Carry out
seizure precautions. Provide a quiet, darkened
environment. Monitor temperature and vital
signs.
REFERENCES
1. Squire, LF: Fundamentals of Radiology, ed 3. Harvard University
Press, Cambridge, Mass, 1982, pp 2–3.
2. Ibid, p 3.
3. Ibid, p 3.
4. Ibid, pp 4, 210.
5. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed
4. JB Lippincott, Philadelphia, 1992, p 632.
6. Ibid, pp 636–639.
7. Ibid, p 639.
8. Springhouse Corporation: Nurse’s Reference Library:
Diagnostics, ed 2. Springhouse Corporation, Springhouse, Pa,
1986, pp 774–745.
9. Ibid, p 754.
10. Ibid, p 754.
11. Fischbach, op cit, p 642.
12. Miller, WT: Radiologic examination of the chest. In Fishman, AP:
Pulmonary Diseases and Disorders, ed 2, vol I. McGraw-Hill, New
York, 1988, p 525.
13. Nurse’s Reference Library, op cit, p 652.
14. Squire, op cit, p 28.
15. Nurse’s Reference Library, op cit, p 652.
16. Miller, op cit, p 479.
17. Nurse’s Reference Library, op cit, p 653.
18. Miller, op cit, p 479.
19. Nurse’s Reference Library, op cit, p 653.
20. Miller, op cit, p 480.
21. Squire, op cit, p 16.
22. Nurse’s Reference Library, op cit, p 657.
23. Umali, CB, and Smith, EH: The chest radiographic examination.
In Reppe, JM, et al: Intensive Care Medicine. Little, Brown & Co,
Boston, 1985, pp 484–485.
24. Nurse’s Reference Library, op cit, p 956.
25. Fischbach, op cit, p 646.
26. Ibid, p 646.
27. Nurse’s Reference Library, op cit, p 955.
28. Squire, op cit, pp 168–171.
29. Pagana, KD, and Pagana, TJ: Mosby’s Diagnostic and Laboratory
Test Reference. Mosby–Year Book, St Louis, 1992, pp 527–528.
30. Ibid, pp 527–528.
31. Ibid, p 549.
32. Ibid, p 549.
33. Ibid, p 550.
34. Ibid, p 550.
35. Ibid, p 681.
36. Ibid, p 681.
37. Corbett, JV: Laboratory Tests and Diagnostic Procedures with
Nursing Diagnoses, ed 3. Appleton & Lange, Norwalk, Conn,
1992, p 519.

38. Editorial: Value of bone densitometry to improve the outcomes of
patients with bone loss remains unproven. Research Activities,
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39. Staud, R. Osteoporosis: Guidelines for measuring bone mineral
density. Dual energy x-ray absorptiometry is the imaging modality of choice. J Musculoskeletal Medicine, 15(9): 25–32, Sept 1998.
40. Lenchick, L, Rochims, P, and Sartoris, D: Optimized interpretation and reporting of dual x-ray absorptiometry (DXA) scans.
AJR, 171:1508–1519, Dec 1998.
41. Fischbach, op cit, pp 643–644.
42. Ibid, p 643.
43. Nurse’s Reference Library, op cit, p 874.
44. Fischbach, op cit, p 644.
45. Nurse’s Reference Library, op cit, p 874.
46. Pagana and Pagana, op cit, pp 172–173.
47. Nurse’s Reference Library, op cit, pp 657–658.
48. Fischbach, op cit, pp 641-642.
49. Ibid, p 642.
50. Ibid, p 668.
51. Kee, JL: Handbook of Laboratory and Diagnostic Tests with
Nursing Implications, ed 3. Appleton & Lange, Norwalk, Conn,
1997, p 400.
52. Fischbach, op cit, pp 670–671.
53. Nurse’s Reference Library, op cit, p 731.
54. Fischbach, op cit, p 671.
55. Ibid, p 669.
56. Nurse’s Reference Library, op cit, p 731.
57. Fischbach, op cit, pp 670–671.
58. Amberg, JR, and Juhl, JH: The pharynx and esophagus. In Juhl,
JH, and Crummy, AB: Paul and Juhl’s Essentials of Radiologic
Imaging, ed 5. JB Lippincott, Philadelphia, 1987, p 521.
59. Ibid, p 515.
60. Ibid, p 514.
61. Ibid, p 515.
62. Nurse’s Reference Library, op cit, p 818.
63. Amberg, JR, and Juhl, JH: The stomach and duodenum. In Juhl,
JH, and Crummy, AB: Paul and Juhl’s Essentials of Radiologic
Imaging, ed 5. JB Lippincott, Philadelphia, 1987, p 525.
64. Pagana and Pagana, op cit, p 672.
65. Nurse’s Reference Library, op cit, p 821
66. Fischbach, op cit, p 653.
67. Pagana and Pagana, op cit, p 82.
68. Nurse’s Reference Library, op cit, p 824.
69. Fischbach, op cit, p 653.
70. Pagana and Pagana, op cit, p 83.
71. Fischbach, op cit, p 653.
72. Amberg, JR, and Juhl, JH: The gallbladder and biliary ducts. In
Juhl, JH, and Crummy, AB: Paul and Juhl’s Essentials of
Radiologic Imaging, ed 5. JB Lippincott, Philadelphia, 1987, p 496.
73. Nurse’s Reference Library, op cit, p 827.
74. Amberg and Juhl, The gallbladder and biliary ducts, op cit, p 492.
75. Fischbach, op cit, p 654.
76. Nurse’s Reference Library, op cit, p 828.
77. Amberg and Juhl, The gallbladder and biliary ducts, op cit, p 492.
78. Ibid, p 492.
79. Ibid, pp 502–503.
80. Pagana and Pagana, op cit, p 188.
81. Fischbach, op cit, p 655.
82. Pagana and Pagana, op cit, p 183.
83. Ibid, p 187.
84. Ibid, p 184.
85. Fischbach, op cit, p 656.
86. Ibid, p 656.
87. Nurse’s Reference Library, op cit, p 833.
88. Pagana and Pagana, op cit, p 697.
89. Ibid, p 697.
90. Ibid, p 551.
91. Nurse’s Reference Library, op cit, p 831.
92. Wojtowycz, M: Interventional Radiology and Angiography. Year
Book Medical Publishers, Chicago, 1990, pp 313–314.
93. Pagana and Pagana, op cit, p 553.
94. Nurse’s Reference Library, op cit, p 969.
95. Ibid, p 50.
96. Ibid, p 964.
97. Ibid, pp 963–964.

CHAPTER 17—Radiologic

98.
99.
100.
101.
102.
103.
104.
105.
106.
107.
108.
109.
110.
111.

Pagana and Pagana, op cit, p 257.
Ibid, p 256.
Ibid, p 257.
Fischbach, op cit, p 664.
Ibid, p 646.
Nurse’s Reference Library, op cit, p 967.
Ibid, p 971.
Pagana and Pagana, op cit, p 432.
Ibid, p 433.
Berkow, R (ed): The Merck Manual, ed 16. Merck Sharp and
Dohme Research Laboratories, Rahway, NJ, 1992, p 1658.
Pagana and Pagana, op cit, p 435.
Nurse’s Reference Library, op cit, pp 956–957.
Ibid, pp 989–990.
Pagana and Pagana, op cit, p 661.

112.
113.
114.
115.
116.
117.
118.
119.
120.
121.
122.
123.
124.
125.

Ibid, p 662.
Nurse’s Reference Library, op cit, p 674.
Ibid, p 676.
Kee, op cit, p 351.
Pagana and Pagana, op cit, pp 126.
Nurse’s Reference Library, op cit, p 659.
Pagana and Pagana, op cit, p 127.
Ibid, p 127.
Kee, op cit, p 394.
Pagana and Pagana, op cit, pp 424–425.
Ibid, pp 515–516.
Nurse’s Reference Library, op cit, p 781.
Pagana and Pagana, op cit, pp 513–514.
Ibid, p 516.

Studies

437

CHAPTER

Radiologic
Angiography Studies
PROCEDURES COVERED
Cardiac Angiography, 440
Adrenal Angiography, 443
Cerebral Angiography, 444
Pulmonary Angiography, 446
Hepatic and Portal Angiography, 447
Renal Angiography, 449

INTRODUCTION

Mesenteric Angiography, 450
Fluorescein Angiography, 451
Lymphangiography, 452
Upper Extremity Angiography, 453
Lower Extremity Angiography, 454

Angiograms are serial radiographs (x-rays) of blood vessels that are used
to evaluate the patency, size, and shape of the veins (venograms); arteries (arteriograms) of
organs and tissues; or lymph vessels and nodes (lymphograms). They are films taken in rapid
sequence after the injection of an iodinated contrast medium into the vessel or vascular system
to be examined.1
The contrast medium can be hand injected into a peripheral vessel via a needle or into a
major vessel via a needle and catheter, or it can be power injected via a catheter placed directly
into a heart chamber and vessels (cardiac catheterization with angiography) to visualize the
chambers, great vessels, and coronary arteries. Successful visualization of any organ or vessel
depends on the position of the client and catheter, size and type of the catheter or needle
lumen, and the amount and rate of the injection of the contrast medium into the vessel.2
Various types and shapes of catheters are available for angiography, depending on the tip
and length of needle required for the selected vessel to be catheterized (Fig. 18–1). Catheters
vary in diameter and length and are made of polyethylene, nylon, polyurethane, and Teflon
to accommodate ease of handling, insertion, and injection rates.3 Injection rates vary with
blood flow of the vessel to be injected with the contrast medium and range from 2 to 3 mL per
second to a high of 20 to 30 mL per second and a duration range of 2 seconds to 10 or 15
seconds.4
The iodinated contrast media that render the vessels radiopaque for visualization have been
until recently ionic agents such as diatrizoate and iothalamate, but these media are now being
replaced by low-osmolality agents such as iohexol and iopamidol when the additional expense
of these newer agents is warranted. The low-osmolality agents cause less pain and fewer adverse
reactions and allergic responses than do the conventional ionic agents. Fatality rates have also
been reduced with these agents. In rare instances, carbon dioxide can replace the iodinated
contrast medium in clients with poor renal function or potentially life-threatening reactions to
the other media.5 Because severe allergic reactions to iodinated contrast media can result in
438

CHAPTER 18—Radiologic

Angiography Studies

439

Figure 18–1. Catheters used in angiography with selected tips for particular area or vessel to be
catheterized. (A) Cobra type: renal and mesenteric arteries. (B) Headhunter type: femoral artery
approach to brachiocephalic vessels. (C) Pigtail type: aortography. (D) Simmons type: aortic and
brachiocephalic arteries. (Adapted from Wojtowycz, M: Angiography and Interventional Procedures,
Mosby–Year Book, St. Louis, 1990, p 11.)

laryngospasms, anaphylactic shock, and cardiac arrest, emergency equipment should be available so that treatment and resuscitative measures can be instituted immediately.
Arterial access for arteriography is achieved by insertion of a catheter through puncture or
cutdown into a femoral, axillary, or brachial artery and advancement into the specific artery or
vascular system to be examined. Peripheral arteriography can also be achieved by a direct injection of the medium into the target artery, as in the femoral artery.
Venous access for venography is achieved by a direct injection of the contrast medium via
venipuncture or cutdown to expose the vein to visualize and evaluate the blood flow of an area.
It can also be achieved by injection of the dye into a catheter that has been threaded into the
venous system of an organ, as in arteriography, to visualize and evaluate the venous supply to
an area.6 Both peripheral and central veins are studied with venography.
Angiographic procedures are considered invasive, and a signed informed consent is
required. Client preparation is similar to that for a minor surgical procedure, with local anesthesia usually administered for an adult and general anesthesia given to a child or an adult who
is unable to cooperate. Cardiopulmonary resuscitation equipment should be available during
all angiographic studies. The procedures are performed in a special angiography laboratory or
treatment room by a physician with special education and expertise in such procedures. All
angiographic procedures are performed under strict sterile conditions and use standard
precaution procedures.

CONVENTIONAL FILM
ANGIOGRAPHY

DIGITAL SUBTRACTION
ANGIOGRAPHY

Angiographic films are obtained in rapid succession
by special magazines and film changers containing
continuous rolls that allow six films per second to be
taken. Spot films can also be taken, but they may not
produce the desired fine detail. Exposures are made
at a rate and for a duration related to the problem
being studied. These films have the advantage of
providing a large field of view, a high spatial resolution, and the opportunity to use different filming
techniques.7 The studies are developed and reviewed
before the procedure is concluded.

Digital subtraction angiography is a radiologic
method of visualizing details of the vascular system
after the intra-arterial injection of a contrast
medium, usually in lower amounts than with
conventional filming. Its greatest advantage is the
removal of images of the surrounding tissue (bone
and soft tissue) that interfere with the view of the
vessels to be studied. The technique uses a computer
to subtract images in real time and store them electronically on a videocassette. This technique allows
immediate review of the angiogram on a television

440

SECTION II—Diagnostic

Tests and Procedures

monitor. More simply stated, the process involves
fluoroscopic images taken before and after injection
of the medium with the C-arm of the machine
rotated into a lateral projection that provides a
visual field. The images taken before the medium is
injected are subtracted from the images taken after
the medium is contained in the vascular system. This
type of study is particularly useful in the detection of
carotid and cerebral conditions that cause bloodflow abnormalities. Other vessels such as the aorta
and renal, abdominal, and peripheral (ankle and
foot) arteries are also studied using this technique.8
A disadvantage of this method is that the client
must be able to remain still and cooperate for the
length of time it takes to obtain the films. If such
cooperation is not possible, conventional filming is
indicated.

given to counteract the prolonged PT or PTT, such
as fresh frozen plasma if warfarin (Coumadin) is the
drug taken orally and protamine sulfate if heparin is
the drug given intravenously (IV) or subcutaneously
(SC).10

ANGIOGRAPHIC PROCEDURES
Angiographic procedures are named for the type of
vessel to be studied and the method or route of the
injection. Among the vessels are arteries (coronary,
aorta), veins (peripheral, deep central), or lymphatics. Also included are the vascular system of organs
such as the brain, heart, lungs, bronchi, adrenal
glands, liver, pancreas, retina, and kidneys, and parts
of the body such as the extremities.

CARDIAC ANGIOGRAPHY
ANGIOGRAPHY RISKS
All angiographic studies carry some risk to the
client. The risk of injury can be direct or indirect.
Direct injuries involve bleeding at the puncture site,
resulting in hematoma, and can be serious enough
to require transfusion or surgical repair. Indirect
injuries are the result of arterial dissection; rupture
of an aneurysm; vasovagal reactions; and renal,
cardiac, and neurological complications.
Reaction to the contrast medium is also a risk and
can range from sneezing, nausea, and urticaria to
respiratory changes to cardiac collapse and death.
Premedication with antihistamines such as diphenhydramine (Benadryl) and steroids such as methylprednisolone (Medrol) can be administered to
reduce the risk of a reaction, especially in those with
a history of sensitivity to the contrast medium
(iodine) or to shellfish.
Nephrotoxicity is a possible risk that can lead to
renal failure if contrast medium is administered to
clients who have renal insufficiency, diabetes, or
multiple myeloma or who are dehydrated (contrast
medium produces diuresis). Special precautions are
taken to protect the client who has these conditions
by administering a lower dose of the dye, ensuring
adequate hydration via the IV or oral route, and, in
some, administering osmotic diuretics such as
mannitol (Osmitrol) and loop diuretics such as
furosemide (Lasix) to ensure renal flow.9
Clients receiving anticoagulant therapy should
have the medication discontinued or reduced before
the procedure to prevent excessive bleeding or possible hemorrhage. Prothrombin time (PT) or partial
thromboplastin time (PTT) can be performed to
determine whether the risk for emergency angiography is too high or whether medications should be

Cardiac and thoracic angiography involves the
examination of the heart, great vessels, and coronary
arteries (Fig. 18–2). A cardiac catheterization is
performed with a catheter inserted into a vein or
artery and guided through the vascular system into
the left or right side of the heart. The femoral or the
brachial artery is the insertion site usually used for
left cardiac catheterization and the femoral or the
antecubital vein is used for right cardiac catheterization. Films that allow for visualization of the heart
structures and activity by cineangiography during
and after injection of the dye are taken at a variety of
angles as the table is tilted. The client can watch the
procedure on a screen, if desired.
A variety of disorders can be diagnosed, depending on which side of the heart is catheterized and
studied. Pulmonary artery abnormalities are identified with right heart examination; coronary artery
and thoracic aorta abnormalities are identified with
left heart examination. The procedure can be
performed for therapeutic reasons as well as diagnostic purposes. Special attention is needed and
given to provide support and allay the anxiety associated with procedures involving the heart.
Many additional studies of heart structure and
function can also be performed during the procedure (see Chapter 24, “Cardiac Catheterization
Study” section).
Reference Values
Normal patent coronary arteries and great
vessels; no evidence of coronary artery obstruction and aortic aneurysm, trauma, or other
abnormalities

CHAPTER 18—Radiologic

Angiography Studies

441

Figure 18–2. Coronary arteries
and large vessels.

INTERFERING FACTORS

Inability of client to cooperate in the procedure
when local anesthesia is used
Catheter occlusion caused by stagnant blood
Atherosclerotic lesions of the vessel to be cannulated, preventing passage of the catheter
Selection of improper catheter and tip or use of
incorrect technique
INDICATIONS FOR CARDIAC ANGIOGRAPHY

Chest pain, especially in clients with cholesterol
levels above normal range
Coronary artery disease, especially in clients with
a family history of heart disease
Identification of abnormalities after questionable
results from resting or exercise electrocardiographic (ECG) studies
Evaluation of angina with frequent and severe
episodes of chest pain
Detection of abnormal coronary circulation and
degree of occlusion of the arteries that indicate
atherosclerotic disease
Detection of the extent of heart damage in heart
disease
Identification of myocardial infarction site and
performance of infusion procedure of streptokinase or other thrombolytic agent into the
occluded vessel11
Evaluation of cardiac status in preparation for
cardiac bypass surgery or angioplasty when a
decreased coronary perfusion is demonstrated
Evaluation of cardiac function and vessel patency
after surgery or angioplasty
Persistent symptoms (e.g., chest pain) after
cardiac revascularization
Location and determination of the extent of
aortic aneurysm and the presence of atherosclerosis of the arch of the great vessel

Diagnosis of aortic abnormalities by left heart
examination such as tumor, diverticula, aortitis,
and trauma that create tears or other disruption
of the vessel
Evaluation of progress or decline in condition to
enable adjustment of existing medical regimen
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing
the procedure greatly outweigh the risks to the
fetus
Allergy to radiopaque contrast medium, unless
prophylactic medications are administered before
the procedure
Severe cardiomegaly
Poor or severely impaired renal function
Poor surgical risk or refusal to undergo surgery if
recommended after the procedure
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That a physician will explain and perform the
procedure
That the time required to complete the procedure
varies with the type of examination performed for
diagnostic or therapeutic purposes but that it can
be 1 to 3 hours
That foods and fluids are withheld for 4 to 8 hours
before the procedure
That some medications can be withheld for 8
hours before the procedure, depending on the
client and the reason for medications taken; that
anticoagulants will be withheld or dosage reduced
to prevent excessive bleeding; and that aspirin
products are withheld for at least a week before
the procedure
That an analgesic, sedative, or antianxiety agent
can be administered by injection before the proce-

442

SECTION II—Diagnostic

Tests and Procedures

dure to promote relaxation and alleviate discomfort, depending on physician orders
That the client is requested to lie still throughout
the procedure
That an IV line is initiated before the procedure to
provide access for the administration of fluids and
medications when needed
That the catheter insertion site will be anesthetized by local injection
That the client may experience some pressure as
the catheter is introduced into the vessel and a
feeling of warmth and possible palpitations when
the dye is injected, but that this lasts only about 30
seconds
That cough, nausea, and headache may be experienced during the procedure or that chest pain
may develop during the injection or during exercises that are part of the examination and that
medications are given if these side effects occur
That continuous monitoring by ECG and vital
signs is performed during and after the procedure
That bed rest is required for about 8 to 12 hours
after the procedure to monitor the insertion site
and vital signs and to observe the client for signs
of complications, although complications are rare
Prepare for the procedure:
Ensure that dietary, fluid, and medication restrictions have been followed before the procedure.
Obtain a history of allergies or sensitivities to the
anesthetics or contrast medium; existing heart,
lung, or renal condition; and date of last
menstrual period in women of childbearing age to
determine the possibility of pregnancy.
Ensure that hematologic status and blood clotting
ability have been assessed to include complete
blood count, platelet count, PT, PTT, clotting
time, and bleeding time as well as routine urinalysis and electrolytes. Note and record results of
ECG and chest x-ray.
Remove all metallic objects, but allow client to
wear dentures, hearing aids, or both.
Obtain and record baseline vital signs, using
peripheral pulses on the appropriate extremity.
Mark these sites on the skin to ensure that the
same location is used to monitor and compare
readings to assess circulatory status after the
procedure.
Shave and cleanse insertion site if needed.
Have client void.
Administer premedication SC or intramuscularly
as ordered. (Premedication can include an analgesic such as meperidine [Demerol], a sedative
such as diazepam [Valium], or an antihistamine
such as diphenhydramine to prevent an allergic

reaction in those with a history of sensitivity to
iodine.)
THE PROCEDURE

The client is placed on a tilting type x-ray table in a
supine position with straps in place to prevent
falling and to keep the client very still during the
procedure. Cardiopulmonary resuscitation equipment, defibrillator, pacemaker, and cardiac medications should be on hand during and after the
procedure.12 The operating room is notified of the
procedure in the event that emergency cardiac
surgery is necessary.
The leads from the ECG machine are attached to
the chest for continuous monitoring. An IV access
line is initiated to keep the vein open for the administration of fluids and drugs when needed. The site is
cleansed and draped to prepare a sterile field. A local
anesthetic is injected at the site, and a small incision
is made. The room is darkened, and a needle with a
guide wire is inserted. When the needle and guide
wire are placed in the desired site in the heart and
coronary vessels or great vessels, the needle only is
removed, and the catheter is threaded onto the wire
and advanced into the vessel under the guidance of
fluoroscopy. The guide wire is then removed, and the
catheter is flushed with heparinized saline solution
to remove any stagnant blood, a procedure that is
repeated every 3 minutes throughout the study.13
The catheter is advanced through the selected vein to
the inferior vena cava and then to the right atrium
and ventricle if the right side is being catheterized or
through the selected artery to the aorta and into the
coronary arteries if the left side is being catheterized.
The coronary arteries can be catheterized singly to
evaluate patency. After correct placement and flushing of the catheter, the iodinated contrast medium is
injected and controlled at a rate determined by the
studies to be performed. A rapid series of x-rays are
taken during and after the injection.
During the procedure, the client can be requested
to deep-breathe or cough to counteract nausea and
to ease catheter placement into the pulmonary
artery as well as to move the diaphragm in a downward position to allow for clearer visualization of the
heart.14 Filming takes place with the table tilted in
different positions, and the client is turned from side
to side to obtain views of the heart at a variety of
angles. Vital signs and heart activity are monitored
continuously to observe for dysrhythmias that can
occur during the procedure. The procedure is terminated if severe chest pain, cardiac dysrhythmias, or
symptoms of cerebral accident are noted. When the
procedure is completed, protamine sulfate is admin-

CHAPTER 18—Radiologic

istered to counteract the effect of the heparin and to
prevent excessive bleeding. The catheter is removed,
the incision site sutured, and a bandage applied and
taped in place.
NURSING CARE AFTER THE PROCEDURE

Remove the client from the x-ray table and place
him or her at rest for 8 to 12 hours after the procedure to prevent bleeding from the puncture site.
Time at rest should depend on pressure at the
insertion site (venous or arterial) and whether
more than one site was used.
Elevate the head of the bed to 45 degrees and
extend the extremity used for the insertion site.
Immobilize the extremity with a sandbag, 8 hours
for a leg and 3 hours for an arm.
Inspect the insertion site for bleeding or
hematoma formation, and change the pressure
dressing as needed.
Apply ice to the site to relieve discomfort and
edema by promoting vasoconstriction of the
vessels at the site.
A mild analgesic can be administered for site pain.
Assess skin color, sensation, and temperature of
the extremity to determine circulation status. Take
peripheral pulses of the extremity used and
compare with preprocedure pulses and pulses of
the other extremity.
Perform this assessment every 15 minutes for the
first hour, then every 30 minutes for the next 2
hours, and then every hour for the next 8 hours or
more if needed.
Take vital signs and apical pulse at the same
frequency.
Encourage movement in bed from side to side to
exercise uninvolved body parts.
To prevent dehydration and promote excretion of
the dye, encourage fluids, first via the IV line and
then orally, when client is able.
Sutures, if used, are removed in a week.
Reaction to anesthetic agent or contrast medium:
Note and report tachycardia, dyspnea, hyperpnea,
or delayed feeling of itching (urticaria, rash).
Administer antihistamines and steroids. Initiate
oxygen and resuscitation procedure if needed.
Dysrhythmias, cardiac tamponade: Note and
report irregular pulse, postprocedural ECG
changes, or signs and symptoms of cardiac
tamponade such as anxiety, tachypnea, muffled
heart sounds, distended neck veins, or narrowing
pulse pressures. Administer ordered cardiac
medications. Monitor vital signs and cardiac
activity via ECG.
Thrombophlebitis: Note and report pain,

Angiography Studies

443

redness, swelling at the site, or changes in the
peripheral pulses. Monitor site for changes. Apply
ordered warm compresses.
Infection at the insertion site: Note and report
pain, swelling, or drainage. Administer ordered
analgesic and antibiotic therapy. Apply heat treatments.
Bleeding, hematoma: Note and report excessive
bleeding from the insertion site or presence of a
hematoma. Apply pressure for 15 minutes after
the procedure. Apply ice bag and pressure dressing.

ADRENAL ANGIOGRAPHY
Adrenal angiography allows x-ray visualization of
the arteries or veins of the adrenal glands. For both
arteries and veins, an iodinated contrast medium is
injected via the femoral artery or through vein
catheterization, depending on whether an arteriogram or a venogram procedure is to be performed.
Fluoroscopy provides viewing during the advancement of the catheter to ensure proper placement in
an artery or vein. Adrenal arteriography is
performed to determine the presence of a tumor or
hyperplasia of one or both of the glands, and venography is performed to obtain blood samples from
the glands for laboratory analysis. Adrenal complications depend on the type of vessel used and the effect
of the pressure placed on the gland tissue by the dye.
The presence of a pheochromocytoma can lead to a
severe hypertensive crisis and death. - and Adrenergic blockers are administered for several
days before the procedure to prevent this life-threatening condition if a tumor is suspected.15
Reference Values
Normal arteries and veins of the adrenal glands;
no evidence of tumor, abnormal hormones, or
abnormal catecholamine levels
INTERFERING FACTORS

Inability of client to cooperate and lie still during
the procedure when it is performed under local
anesthesia
Atherosclerotic lesions causing obstruction or
narrowing of the vessel to be cannulated, preventing passage of the catheter
Incorrect catheter lumen size and tip
INDICATIONS FOR ADRENAL ANGIOGRAPHY

Suspected benign or malignant adrenal tumor

444

SECTION II—Diagnostic

Tests and Procedures

such as pheochromocytoma, adenoma, or carcinoma diagnosed by arteriography
Diagnosis of adrenal hyperplasia in both glands
by arteriography
Differentiation among adrenal tumor types and,
by arteriography and venography of both glands,
determination of unilateral or bilateral tumor
Securing of a blood sample from the adrenal vein
of each gland for analysis of cortisol levels to diagnose Cushing’s syndrome, with an elevation from
one gland indicating a tumor and from both
glands indicating hyperplasia
Securing of a blood sample from the adrenal vein
for analysis of catecholamines to determine the
presence of a unilateral or bilateral pheochromocytoma, with an elevation from one gland indicating the tumor on that side, elevation from both
glands indicating the tumor on both sides, and
absence of elevated level from either side but presence of elevated level in a peripheral venous blood
sample indicating a tumor external to the gland16
Evaluation of adrenal venous blood for other
hormones and substances such as androgen or
aldosterone17
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodinated contrast medium, unless
prophylactic medications are administered or
nonionic contrast medium is used
Presence of bleeding disorder
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any angiographic procedure (see
section under “Cardiac Angiography”).
Assess the client suspected of having a pheochromocytoma for administration of - and adrenergic blockers (propranolol [Inderal] and
phenoxybenzamine [Dibenzyline]) several days
before the procedure to avoid the risk of a hypertensive crisis.
THE PROCEDURE

The client is placed on the x-ray table in a supine
position. The groin is cleansed and draped to
prepare a sterile field for the procedure. The site is
anesthetized with a local injection, and a catheter is
inserted into the femoral vein for venography and
into the femoral artery for arteriography. The client
should be informed that some pain is experienced at
the puncture site when the catheter is inserted. For
arteriography, the catheter is advanced into the aorta
and then into the inferior adrenal artery via the renal

artery. For venography, the catheter is advanced into
the adrenal vein. Both are guided and placed into
position with the assistance of fluoroscopic visualization. Dye is injected into the catheter; then x-ray
films are taken for arteriographic studies and blood
is obtained for laboratory examination with venographic studies. At the conclusion of the study the
catheter is removed, and a pressure dressing is
applied to the insertion site and taped in place.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
ECG monitoring is not necessary, but electronic
monitoring of blood pressure should be
performed every 15 minutes to intervene in or
offset an imminent hypertensive crisis.
Complications and precautions: With the exception of dysrhythmias, these measures are the same
as for any angiographic procedure (see section
under “Cardiac Angiography”), with the following additions:
Hemorrhage at gland site: Note and report signs
and symptoms of adrenal insufficiency such as
hypotension, muscle weakness, fatigue, nausea,
or sodium and potassium imbalance if gland
function has been affected. Administer replacement therapy as ordered.
Hypertensive crisis: Note and report blood pressure elevations, tachycardia, anxiety, or sweating. Administer ordered antihypertensives or
sympathetic inhibitors. Ensure that - and adrenergic blockers have been administered
before the procedure.

CEREBRAL ANGIOGRAPHY
Cerebral angiography involves x-ray visualization of
the cerebral vessels and the carotid and vertebral
arteries (Fig. 18–3). After the injection of an iodinated contrast medium via catheterization of the
femoral (most common site), the carotid, or the
brachial artery, a series of films are taken to obtain
views with the client in various positions. The
femoral site allows visualization of any vascular area
in the brain or in the carotid or vertebral arteries in
which an abnormality is suspected, whereas the
other sites are more area and vessel specific.
Cerebrovascular abnormalities can be diagnosed
by the changes in the size of the vessel lumina or by
vessel occlusion. Tumor detection, whether vascular
or nonvascular, can be diagnosed by vessel displacement indicating the position and type of tumor.
Vascular displacement can also be identified in

CHAPTER 18—Radiologic

Angiography Studies

445

Figure 18–3. Carotid, vertebral,
and cerebral vessels.

conditions such as abscess, hematoma, and
edema.18,19
Reference Values
Normal structure and patency of cerebral vessels
and carotid and vertebral arteries; no evidence
of cerebral aneurysm, plaques, or spasms;
thrombosis; fistulae; tumor; arteriovenous (AV)
malformation; or hematoma

INTERFERING FACTORS

Inability of client to lie still and keep head immobilized during the procedure
Atherosclerotic lesions causing narrowing or
obstruction of the vessel to be cannulated and
difficulty in passage of the catheter
INDICATIONS FOR CEREBRAL ANGIOGRAPHY

Detecting vascular or nonvascular tumor by vessel
displacement
Detecting spasms, abscess, edema, or hematoma
by vascular distortion, displacement, or both
Detecting abnormalities or interruptions in cerebral circulation through the narrowing or occlusion of vessels caused by thrombosis or detecting
AV malformation
Detecting vessel wall changes caused by aneurysm
Detecting atherosclerosis and degree of occlusion
of the carotid arteries
Diagnosing hydrocephalus in an infant or young
child

Determining increased intracranial pressure and
possible cause
Evaluating postoperative placement and status of
shunts or clips to vessels
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodinated contrast medium, unless
prophylactic medications are administered or
nonionic dye is used for those suspected of iodine
sensitivity
Presence of a bleeding disorder
Acute or severe renal or hepatic disease
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
THE PROCEDURE

The client is placed on the x-ray table in a supine
position. The arms are placed at the sides, and the
head is immobilized with sandbags. The groin
(femoral), arm (brachial), or neck (carotid) site is
cleansed and draped to prepare a sterile field for the
procedure. Site selection depends on previous problems with arterial structure or patency. General
anesthesia is administered if the study is to be
performed on a child; otherwise, the selected site is
anesthetized by local injection. The catheter is
advanced under fluoroscopic guidance, and the dye
is injected for visualization of the carotid and verte-

446

SECTION II—Diagnostic

Tests and Procedures

bral arteries, large vessels of the circle of Willis, and
the cerebrovascular system, including the arterial
branches and venous and capillary blood flow. The
catheter is flushed with heparinized normal saline
during the procedure to prevent stagnation of blood.
A series of x-ray films are taken in sequence to reveal
the complete vascular circulation of the brain in
anterior-posterior (AP) and lateral views.
Neurological checks are made and vital signs are
monitored during the study. Depending on the
results, another timed series of filming can follow,
with additional dye injected. At the conclusion of the
procedure, the catheter is removed and pressure is
applied to the site for 10 to 15 minutes. A dressing is
then applied at the insertion site and taped in place.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
Continue neurological checks and vital sign
monitoring during the period of bed rest every
hour for the first 4 hours and then every 4 hours
for 24 hours for changes in breathing pattern or
orientation, especially if the carotid site was used.
If the carotid site was used, elevate the head
slightly and assess the client for visual, facial, and
speech changes resulting from transient ischemic
attacks or breathing and swallowing changes
caused by neck edema.20
Complications and precautions: With the exception of dysrhythmias, complications and precautions are the same as for any angiographic
procedure (see section under “Cardiac
Angiography”), with the following addition:
Embolism if atherosclerotic plaque is dislodged by
catheter: Note and report change in vital signs
or signs of neurological impairment. Prepare
for emergency intervention.

PULMONARY ANGIOGRAPHY
Pulmonary angiography involves x-ray examination
of the pulmonary vessels after the injection of an
iodinated contrast medium into the pulmonary
artery or a branch of this great vessel. The procedure
is considered the definitive standard for the diagnosis of acute pulmonary embolism, but it can also be
used to identify the presence of other arterial and
venous abnormalities. Chest x-ray and radionuclide
scan are performed before angiography if
pulmonary embolism is suspected in order to rule
out the presence of the abnormality or to direct the
study to the location of a disease or perfusion abnormality that will provide a diagnosis.21

Bronchial-intercostal arteriography involves the
examination of the bronchial and intercostal
arteries to determine the cause of recurrent or
severe hemoptysis and to identify the site of the
bleeding.
Cineangiography and digital subtraction angiography techniques can be used in clients if the advantages outweigh the disadvantages of these
alternatives, such as higher radiation dose, smaller
field size, and risk of a reaction to the contrast
medium.22
Reference Values
Normal structure and patency of the pulmonary
circulation vessels; no evidence of pulmonary
embolism, tumor, aneurysm, stenosis, or AV
malformation
INTERFERING FACTORS

Inability of client to cooperate and remain still
during the procedure
Catheter occlusion caused by stagnant blood
Atherosclerotic lesions causing narrowing or
obstruction of the vessel to be cannulated and
difficulty in the passage of the catheter
INDICATIONS FOR PULMONARY ANGIOGRAPHY

Evaluation of vascular changes in pulmonary
circulation
Detection of filling defects caused by acute
pulmonary embolism when lung perfusion and
ventilation scanning have not provided a definitive diagnosis
Diagnosis of chronic pulmonary embolism
Detection of perfusion defects caused by
aneurysms, arterial hypoplasia or stenosis, or
thrombi
Detection of vessel displacement caused by
pulmonary tumor
Detection of vascular obstruction caused by
tumor or inflammatory disease, both for diagnosis and after treatment regimen
Recurrent or massive bleeding caused by tuberculosis, bronchiectasis, sarcoidosis, or aspergilloma23
Location of bleeding site before embolotherapy by
performing bronchial and intercostal angiography
Detection and location of pulmonary embolism
before performing an embolectomy in a lifethreatening situation
Planning of treatment or surgical procedure for
congenital heart disease in children

CHAPTER 18—Radiologic

Evaluation of pulmonary vascular changes associated with emphysema, blebs, and bullae
Suspected aortic laceration after trauma
Diagnosis and evaluation of atherosclerotic
aneurysm of the aorta
Evaluation of aortic masses such as invading
tumor or diverticulum
Evaluation of aortic aneurysm and dissection
before surgery
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing
the procedure greatly outweigh the risks to the
fetus
Allergy to the iodinated contrast medium, unless
prophylactic medications are administered or
nonionic dye is used
Presence of a bleeding disorder
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
THE PROCEDURE

The client is placed on the x-ray table in a supine
position. The leads from the ECG machine are
attached to the chest to provide continuous monitoring of the heart’s activity to identify dysrhythmias
during the procedure. The site is cleansed and
draped to prepare a sterile field for the procedure. A
local anesthetic is injected at the site, and a small
incision is made or a needle inserted. The catheter is
inserted into the femoral, brachial, or jugular vein
and threaded into the inferior vena cava, then into
the right side of the heart under fluoroscopic guidance. From the right ventricle, the catheter is placed
in the pulmonary artery and the dye is injected. If
aortography is to be performed, the femoral artery is

Figure 18–4.
vessels.

Hepatic arterial

Angiography Studies

447

the site of insertion, and the catheter is placed near
the aortic valve before injection of the dye. Injection
rate is dependent on the area to be examined. If
bronchial angiography is to be performed, the
catheter is advanced into the descending thoracic
aorta and then into the right intercostobronchial
trunk and one or two left bronchial arteries before
the dye is injected.24 Serial films are taken during
the injection of the dye to visualize pulmonary
circulation. Rapid sequence films with at least two
views of each lung are obtained after the dye
injection. When the procedure is completed, the
catheter is removed, and pressure is applied at the
site. A pressure dressing is then applied and taped in
place.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).

HEPATIC AND PORTAL ANGIOGRAPHY
Hepatic angiography allows x-ray visualization of
the hepatic arterial and venous systems after injection of a contrast medium in an amount and at a
rate based on the vessel and the suspected liver
abnormality. Normally, the liver blood circulation is
supplied by the hepatic artery and the portal vein.
Figure 18–4 portrays the hepatic arterial and venous
anatomy involved in this procedure.
Portal venography is performed to assess the
patency and size of the portal, splenic, and mesenteric veins. The direction of blood flow and collateral vessel development can also be evaluated.
Abnormalities involving the hepatic artery are
revealed if a malignant tumor is present. Venous
invasion is revealed in hepatocellular carcinoma
resulting from hepatitis and cirrhosis.25

448

SECTION II—Diagnostic

Tests and Procedures

Reference Values
Normal structure and patency of hepatic artery
and portal vein; no evidence of tumors, vascular
obstruction, or other liver abnormalities

INTERFERING FACTORS

Inability of client to cooperate and remain still
during the procedure
Atherosclerotic lesions causing narrowing or
obstruction of the vessel to be cannulated and
difficulty in passage of the catheter
INDICATIONS FOR HEPATIC AND PORTAL
ANGIOGRAPHY

Diagnosis of malignant liver tumor when other
diagnostic procedures such as ultrasonography,
computerized scanning, magnetic resonance
imaging, or needle biopsy fail to provide a definitive diagnosis (Note: Malignant tumors are
supplied by the hepatic artery only, whereas the
normal liver is diffused by both arteries and
veins.)
Determination of the location, number of nodes,
and vascular invasion of a hepatic malignant
tumor before surgery
Determination of the advisability of arterial
infusion of chemotherapy to treat a malignant
tumor
Determination of the stage of cirrhosis of the
liver, which is known to cause a reversal of portal
venous blood flow
Evaluation of liver trauma after injury (Note:
Diagnostic value of the procedure is questionable
for this condition.26)
Definition and determination of hepatic anatomy
and blood flow before hepatic transplantation or
shunt placement
Postoperative evaluation of the surgical placement of a portosystemic shunt
Evaluation of portal vein patency and size after
hepatic transplantation
Diagnosis of nodular hyperplasia or Budd-Chiari
syndrome, which causes hepatic venous flow
obstruction
Evaluation of tumors of the pancreas or other
intra-abdominal masses before surgery to determine advisability of resection
Suspected mesenteric venous thrombosis or
varices of the colon or small bowel
Determination of portal vein pressure to diagnose
portal hypertension as well as other liver diseases
that produce venous obstruction27

CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodinated contrast medium, unless
prophylactic medications are administered before
the procedure or a nonionic dye is used
Bleeding disorder or severely impaired liver or
renal function
Presence of ascites
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
ECG monitoring of heart activity is not necessary
for this procedure unless the client’s cardiovascular status is at risk.
THE PROCEDURE

The client is placed on the x-ray table in a supine
position. The site—usually the femoral for the indirect approach or the upper right quadrant for the
direct approach—is cleansed and draped to prepare
a sterile field for the procedure. The site is anesthetized by local injection. Portal angiography
requires a direct approach that involves transhepatic
or transplenic insertion of a needle through the skin,
as in percutaneous transhepatic cholangiography,
into the splenic or superior mesenteric vein followed
by the injection of the contrast material. Portal
venous pressure can be taken with this procedure
before x-ray filming by the insertion of the catheter
into the hepatic vein until it occludes blood outflow
from the vein.28 In the indirect approach used for
hepatic arteriography or venography, the femoral
site is used. The catheter is inserted into the femoral
artery and advanced to the common hepatic artery
via the superior mesenteric artery or gastric artery in
arteriography. The catheter is inserted into the
femoral vein and advanced into the major hepatic
vein for venography. All catheter or needle placements are guided by fluoroscopic viewing.
Dye injection rates depend on the flow rates
within the vessels and the projected length of times
needed for filming. Filming after dye injection is
rapid for a few seconds and then slowed for about 30
seconds to include parenchymal and venous phases
of hepatic arteriography and portography. When the
procedure is completed, the catheter or needle is
removed and pressure is applied to the site. A pressure dressing is then applied and taped in place.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the

CHAPTER 18—Radiologic

same as for any angiographic procedure (see section
under “Cardiac Angiography”).
Liver or splenic hemorrhage: Note and report
changes in vital signs, such as tachycardia,
hypotension, or abdominal pain. Administer
ordered blood transfusion. Prepare for possible
splenectomy in extreme cases.

RENAL ANGIOGRAPHY
Renal angiography allows x-ray visualization of the
large and small arteries of the renal vasculature and
parenchyma or of the renal veins and their branches,
depending on the studies to be performed. It can be
done to determine the vascularity, arterial supply,
and extent of venous invasion in the evaluation of
renal tumors as well as to identify other abnormalities and to study prospective renal donors.29
The study is performed by catheterization of the
femoral artery or vein, with the advancement of the
catheter through the iliac artery and aorta into the
renal artery or into the inferior vena cava and renal
vein. Imaging for caval patency followed by imaging
to study the renal arterial, parenchymal, and venous
phases can be performed with the catheter in the
inferior vena cava. Depending on the results, insertion of an arterial catheter can follow, including
aortography with subsequent arterial examination.
Reference Values
Normal structure, function, and patency of
renal vessels; no evidence of obstruction,
malformations, cysts, tumors, or variations in
number and size of vessels and organs
INTERFERING FACTORS

Inability of client to cooperate and remain still
during the procedure
Failure to withhold sodium in the diet or medications that interfere with the accurate analysis of a
blood sample taken for renin in renal venography
Presence of gas or feces in the gastrointestinal
tract or barium left in the tract from recent radiologic studies
INDICATIONS FOR RENAL ANGIOGRAPHY

Persistent hematuria of unresolved cause
Detection of renal tumors by the arterial supply,
extent of venous invasion, and tumor vascularity
Differentiation between tumors and renal cysts
for operative planning
Detection of nonmalignant tumors before surgical resection

Angiography Studies

449

Evaluation of renovascular hypertension caused
by the atherosclerotic lesions that result in the
narrowing or occlusion of arteries and renal
insufficiency
Suspected renal artery stenosis causing vessel dilation, collateral vessel formation, or increased
renovascular pressure
Suspected arterial occlusion caused by transection
of the renal artery as a result of trauma or penetrating injury
Detection of abscess or inflammatory conditions,
aneurysm, or AV abnormalities revealed by renal
arteriography
Definition of arterial anatomy to evaluate the
vascularity of a tumor before surgery or
embolization
Evaluation of anatomy of renal vascular system of
prospective kidney donors to detect unsuspected
renal disease before surgery30
Evaluation of postoperative renal transplantation
for function or organ rejection
Diagnosis of thrombosis revealed by renal venography
Detection of small kidney or absence of a kidney
Determination of relationship of the renal arterial
vasculature to the aorta
Determination of renal function in chronic renal
failure, end-stage renal disease, or hydronephrosis
Collection of a sample of blood from the renal
vein for renin analysis in the diagnosis of renovascular hypertension31
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodinated contrast medium, unless
prophylactic medications are administered before
the study
Bleeding disorder
End-stage renal failure or severe thrombosis of the
inferior vena cava or renal vein32
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
Advise the client to eat a special salt-free diet and,
if venography is planned to obtain a blood sample
for renin level, restrict current medications that
include antihypertensives, diuretics, or hormones
before the procedure.
Administer a laxative the day before or an enema
the day of the study to clear the bowel of feces or
barium if ordered.

450

SECTION II—Diagnostic

Tests and Procedures

Figure 18–5. Abdominal aorta,
superior and inferior mesenteric
arterial vessels.

THE PROCEDURE

The client is placed on the x-ray table in a supine
position. The site, usually femoral, is cleansed and
draped to provide a sterile field for the procedure.
The site is injected with a local anesthetic, and the
artery (renal arteriography) or vein (renal venography) is punctured and the guide wire inserted. The
catheter is inserted over the guide wire and advanced
into the aorta and then into the renal artery for arteriography or into the inferior vena cava and then the
renal vein for venography. Catheter advancement
and placement are achieved under the guidance of
fluoroscopic viewing. Blood samples can be
obtained from each renal vein for analysis in venography. The contrast medium is injected, and a series
of rapid x-rays are taken during and after the filling
of the vessels to be examined. Filming can also take
place after the dye injection for additional delayed
studies or for filming the venous phase of the procedure. At the conclusion of the study, the catheter is
removed and pressure is applied to the site. A pressure dressing is then applied and taped in place.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
Renal function tests such as blood urea nitrogen
and creatinine are performed if compromised
renal function as a result of the test is suspected.

MESENTERIC ANGIOGRAPHY
Mesenteric angiography involves the x-ray examination of the gastrointestinal vasculature after the
injection of an iodinated contrast medium. Serial
films that include arterial, capillary, and venous
perfusion are taken of the abdominal vasculature.
The catheter is inserted into the femoral artery with
the advancement into the aorta followed by place-

ment into the superior or inferior mesenteric artery
or the celiac artery (Fig. 18–5).33
The study can include therapeutic as well as diagnostic angiographic procedures involving the
abdominal aorta to identify abnormalities and the
stomach, pancreas, and small and large intestines to
identify an acute bleeding source and perform
perfusion or embolization to control the hemorrhage.
Reference Values
Normal vascular structure and patency; no
bleeding activity or ischemia in the blood vessels
of the gastrointestinal organs

INTERFERING FACTORS

Inability of client to cooperate and remain still
during the procedure
Atherosclerotic lesions in the vessel to be cannulated, preventing passage of the catheter
Presence of gas or feces in the gastrointestinal tract or barium remaining from radiologic studies
INDICATIONS FOR MESENTERIC ANGIOGRAPHY

Diagnosing colonic diverticula, angiodysplasia,
Meckel’s diverticulum, or inflammatory bowel
disease, all of which could become a source of
internal bleeding
Determining the source and cause of stomach,
pancreas, or small- or large-bowel bleeding when
other diagnostic procedures such as endoscopy,
radionuclide scan, or barium studies have failed to
reveal or resolve the problem
Identifying bleeding site in the tract before
surgery or treatment to control hemorrhage
Determining the status of mesenteric circulation
or the condition of the iliac or common femoral

CHAPTER 18—Radiologic

arteries before surgery to correct and perform
graft for abdominal aortic aneurysm
Infusing arterial vasopressin (Pitressin) or
performing arterial embolization therapy with a
gelatin sponge (Gelfoam) when other measures
have failed to control bleeding
Detecting portal or mesenteric venous thrombosis during the venous phase of the study
Diagnosing acute mesenteric ischemia in the presence of thrombus, embolus, or venous occlusion
Evaluating the extent of a suspected abdominal
aortic aneurysm
Detecting islet cell tumor of the pancreas not
diagnosed by other studies such as ultrasonography or computerized scanning34
Evaluating suspected aortoenteric fistula of intestinal angina35
Detecting type (splenic or hepatic) and extent of
rupture or injury from trauma that affects major
vessels
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
Allergy to iodinated contrast medium, unless
prophylactic medications are administered before
the study
Bleeding or coagulation disorder
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
Administer a laxative the day before or an enema
the day of the study to clear the bowel of feces or
barium if ordered.

Angiography Studies

451

lary and venous phases to complete the study. At the
conclusion of the study, the catheter is removed, and
pressure is applied to the site. A pressure dressing is
then applied and taped in place.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
Assess and monitor vital signs if therapeutic
procedures were performed to control bleeding
in order to determine whether bleeding is persisting.

FLUORESCEIN ANGIOGRAPHY
Fluorescein angiography is the rapid filming in color
of the retinal vasculature and circulation after the IV
injection of a contrast medium known as sodium
fluorescein. The study is performed to diagnose eye
abnormalities caused by changes in the retinal
vasculature. The dye is rapidly injected into the antecubital space (vein) and within 12 to 15 seconds fills
the arteries, capillaries, and veins of the retina.36
A special camera is used for this study instead of
the conventional radiologic equipment. The images
taken in sequence and manipulated by a computer
can provide views of abnormalities during any of the
stages involved in the filling and emptying of the dye
in the retinal vessels.
Reference Values
Normal retina and retinal and choroidal vessels;
no evidence of vascular abnormalities such as
hemorrhage, retinopathy, aneurysm, or obstruction as a result of stenosis

THE PROCEDURE

The client is placed on the x-ray table in a supine
position. An abdominal flat plate film can be taken
at this time. The puncture site, usually the femoral
artery, is cleansed and draped to prepare a sterile
field for the procedure. The site is anesthetized by
local injection, and the catheter is inserted and
advanced into the abdominal aorta under fluoroscopic viewing. Dye is injected for filming of the
aortic structure and patency. After filming of the
abdominal aorta, the catheter is advanced into the
celiac superior or inferior mesenteric artery. The
injection of the dye is adjusted to match the blood
flow of these vessels, and a series of rapid films are
made. The catheter can then be further advanced
into the branches of the major artery, and rapid
sequence films can be made during and after the dye
injection. The filming can then be slowed for capil-

INTERFERING FACTORS

Inability of client to keep eyelids open and eyes in
a fixed position
Presence of cataracts
Improper dilation of pupils
INDICATIONS FOR FLUORESCEIN ANGIOGRAPHY

Detecting vascular disorders that affect visual
acuity
Detecting tumors, retinal edema, or inflammation
by the degree or patterns of fluorescence during
the study
Diagnosing past reduced flow or patency of the
vascular circulation of the retina by presence of
neovascularization
Diagnosing macular degeneration in elderly

452

SECTION II—Diagnostic

Tests and Procedures

persons and any associated hemorrhage that
might be present
Diagnosing diabetic retinopathy caused by longterm diabetes mellitus
Detecting microaneurysms caused by hypertensive retinopathy
Detecting collateral circulation resulting from
arterial or venous occlusion caused by stenosis
with a reduced, delayed, or absent flow of the dye
through the vessels or possible leakage of the dye
from the vessel37
CONTRAINDICATIONS

Allergy to iodinated contrast medium, unless
medications are administered before the study
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the time required to complete the procedure
is about 1 hour
That there are no food or fluid restrictions but
that eye medications should be withheld on the
day of the procedure
That eyedrops to dilate the pupils will be instilled
before the procedure
That the client will be exposed to bright light and
will be requested to remain still and fixate the eyes
during the procedure
That the contrast medium is injected into a vein
in the arm, which will cause some nausea or feeling of warmth for a short time
That the dye can cause skin and urine to appear
yellow for 1 to 2 days after the study
Prepare for the procedure:
Ensure that restriction of eye medications has
been followed.
Obtain a history of allergy to iodine or other
sensitivities, visual problems, and known or
suspected eye conditions.
Remove constricting clothing from the waist up
and provide client with a hospital gown, if
needed.
Have client void.
Obtain and record baseline vital signs for later
comparison readings.
Administer ordered mydriatics for pupil dilation,
usually every 5 minutes for 30 minutes.
THE PROCEDURE

The client is seated in a chair that faces the camera.
The eyes are checked to ensure that dilation has been
achieved. Films are taken by the photographic
camera instead of conventional x-ray before any dye
is injected. An IV line is initiated in the brachial vein
to administer the dye. The client is requested to place

the chin and forehead in position and the head is
immobilized. The client is then requested to open
the eyes wide and look straight ahead. The fluorescein dye is then injected into the vein, and a rapid
sequence of photos is taken and repeated after the
dye has reached the retinal vascular system. Followup photographs are then taken in 20 to 30 minutes.38
At the conclusion of the procedure, the IV needle is
removed and a Band-Aid is applied to the site.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
taking vital signs and comparing them with the
baseline readings.
Inform the client that visual acuity and responses
to light can temporarily change and that dark
glasses can be worn if the client so desires.
Inform the client that driving is restricted for 4
hours after the study or until the pupils return to
normal.
Inform the client that the skin and urine may
develop a yellowish cast for up to 2 days, but it will
then disappear.
Reaction to fluorescein dye: Note and report
delayed feeling of faintness, increased salivation,
dry mouth, urticaria, sneezing, and changes in
breathing pattern. Administer antihistamine and
steroid therapy as ordered.

LYMPHANGIOGRAPHY
Lymphangiography involves x-ray examination of
the lymphatic flow and nodal patterns. The
lymphatic vessels in the foot or hand are injected
with an iodinated oil-based contrast medium such
as Lipiodol or Ethiodol and vital dye such as methylene blue or isosulfan blue. Films are taken in
different positions to provide various views of the
abdomen and chest to reveal the lymphatic channels
and any displacement or collateral formation. The
same films are taken in 24 hours to assess the lymph
nodes, making this a 2-day study to formulate a
diagnosis of neoplastic disease.39 Abnormal findings
include pathological nodes identified by enlargement or filling defects and the presence of
obstructed lymphatic flow patterns. In addition to
this procedure, ultrasonography, computerized scan,
and node biopsy can be performed to substantiate
malignancies.
Reference Values
Normal structure and patency of lymphatic
system and nodes; no filling defects, obstruction, or hyperplasia

CHAPTER 18—Radiologic

INDICATIONS FOR LYMPHANGIOGRAPHY

Suspected pathology of the lymphatics, such as
lymphoma or tumor metastasis to lymph nodes,
revealed by node size and filling defects
Determination of the stage of lymphoma between
stage I and stage IV to identify extent of involvement ranging from a single node to diffuse metastasis, especially in Hodgkin’s lymphoma40
Diagnosis of testicular tumor, prostatic carcinoma, and cervical carcinoma when performed in
association with ultrasonography, computerized
scanning, and node biopsy procedures41
Differentiation between primary and secondary
lymphedema in an extremity
Evaluation of nodal involvement before
treat-ment regimen and possible surgical intervention
Evaluation of effectiveness of therapy (chemotherapy or radiation) or progression of the
disease

Angiography Studies

453

fully dissected and then cannulated with a needle
connected to tubing filled with the contrast
medium, usually an ethiodized oil. The dye is slowly
injected into the channel of both feet, and x-ray
films are taken to confirm the filling of the lymphatics. After completion of the study, the needles are
removed and the incisions are sutured. Dressings are
then applied and taped in place.
The filming that follows includes AP and oblique
views of the pelvis and abdomen. A lateral view of
the abdomen and AP view of the chest can also be
filmed.42 These views provide visualization of the
thoracic and supraclavicular as well as the iliac and
aortic nodes. The same procedure performed on the
hands provides visualization of the axillary and
supraclavicular nodes.43 Additional films are taken
in 24 hours and can be repeated for up to 1 year after
the procedure because the oil can remain in the
nodes for that length of time.
NURSING CARE AFTER THE PROCEDURE

CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure outweigh the risks to the fetus
Allergy to the contrast medium, unless prophylactic medications are administered before the study
Poor or severely impaired pulmonary, cardiac,
renal, or hepatic function
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
Inform the client that the procedure can take as
long as 3 hours.
Inform the client that food and fluids are not
restricted and that a temporary blue tinge in the
skin will appear at the entry site and in the urine
and feces after the study because of the dye injection.
THE PROCEDURE

The client is placed on the x-ray table in a supine
position. Injections of Evans blue or methylene blue
dye are administered intradermally into the webs
between the first three toes or into the medial and
lateral webs. The client is requested to walk at this
time to enhance visualization of the lymphatics of
the feet. The feet are then cleansed and draped to
provide a sterile field for the procedure. A local anesthetic is injected over the dorsum of the foot after a
vessel is selected. The client is informed that this
injection causes slight pain. An incision is made
over the selected lymphatic vessel, which is care-

Care and assessment after the procedure are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
Monitor the extremity for sensation changes and
the site for possible infection.
Apply warm compresses to the sites if ordered for
discomfort.
Remind the client to return in 24 hours for more
films.
Inform the client that the skin, urine, and feces
can be blue tinged for about 2 days.
Pulmonary emboli, lipid pneumonia: Note and
report dyspnea, chest pain, or hypotension.
Monitor vital signs, respiratory pattern, and
breath sounds. Administer ordered oxygen and
medications.

UPPER EXTREMITY ANGIOGRAPHY
Upper extremity angiography, not performed as
frequently as lower extremity angiography, involves
x-ray visualization of the arterial or venous system
of the hand and arm after injection of an iodinated
contrast medium (Fig. 18–6). Low-osmolar agents
and digital subtraction angiographic techniques
have reduced the pain associated with the injection of the material to perform this procedure.
Catheterization and injection sites are dependent on
the extent of the arm or hand, or arm and hand, to
be examined and the presenting signs and symptoms
indicating obstruction, ischemia, vasospasms,
lesions, or trauma. Both diagnostic and therapeutic
procedures can be performed.

454

SECTION II—Diagnostic

Tests and Procedures

thrombosis or balloon angioplasty for subclavian
arterial stenosis
CONTRAINDICATIONS

Pregnancy, if filming other than the hand and arm
is planned
Allergy to iodinated contrast medium, unless
prophylactic medications are administered before
the procedure
Edema of the extremity
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
THE PROCEDURE

Figure 18–6. Hand and wrist arterial vessels.

Reference Values
Normal structure and patency of the hand
and arm vascular system; no thrombosis or
obstruction in the veins and no claudication,
aneurysms, or embolization of the arteries
INTERFERING FACTORS

Cold environmental temperature that affects the
vascular tone and blood flow in the digits
Vasospasms that affect the filling of the digital
vessels with dye
INDICATIONS FOR UPPER EXTREMITY
ANGIOGRAPHY

Diagnosis of Raynaud’s phenomenon with or
without a fixed vascular occlusion
Determination of unilateral or bilateral Raynaud’s
phenomenon in the diagnosis of an underlying
arterial condition
Differentiation between atherosclerosis and
thromboangiitis obliterans by the involvement of
proximal or distal vessels, respectively44
Claudication to determine the extent of arterial
involvement
Determination of the cause of embolization, such
as atherosclerosis or aneurysms
Diagnosis of thoracic outlet syndrome by venous
obstruction and thrombosis or arterial compression
Diagnosis of arterial or venous insufficiency
caused by repeated trauma or other injuries such
as thermal or electric shock to the extremity45
Determination of a treatment plan based on study
findings for thrombolysis in arterial or venous

The client is placed on the x-ray table in a supine
position. The groin is cleansed and draped to
prepare a sterile field for a femoral arterial approach.
In cases of proximal disease or atherosclerosis, the
axillary or brachial artery can be used as a site for
cannulation. The site is anesthetized by local injection, and the catheter is inserted and advanced
through the intrathoracic arteries and into the axillary artery for distal injection of the dye and down
into the distal brachial artery if the hand is to be
studied. The dye is then injected, and the filming is
performed. Digital subtraction angiography can also
be performed to reduce the pain associated with the
procedure.
To enhance filling of the vessels, spasms can be
counteracted by the administration of tolazoline
(Priscoline) or phentolamine (Regitine) injected
intra-arterially with immediate filming performed.
The extremity can be warmed with a heating pad
combined with the injection to produce optimal
vascular tone and blood flow for the best filming of
hand angiography.46
At the completion of the procedure, the catheter
is removed and pressure is applied to the site. A pressure dressing is then applied and taped in place.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).

LOWER EXTREMITY ANGIOGRAPHY
Lower extremity angiography allows x-ray visualization of the arteries or veins of the leg or foot after the
injection of an iodinated contrast medium (Fig.
18–7). Abdominal aortography to evaluate
aneurysms preoperatively and pelvic angiography to

CHAPTER 18—Radiologic

Angiography Studies

455

Figure 18–7. Leg and foot arterial and venous vessels.

evaluate mesenteric circulation can also be
performed with these studies.47 In addition to the
diagnostic aspects of the procedure, it can be
performed for therapeutic reasons. Catheterization
or injection sites, or both, are chosen according to
the areas and vessels to be examined. Abnormal
results include filling defects, vasospasms, lesions,
stenosis, and occlusion associated with aortic, arterial, or venous disease.
Reference Values
Normal structure and patency of the leg and
foot vascular system; no arterial occlusion,
embolus, inflammation, or claudication; no
venous thrombosis or incompetence
INTERFERING FACTORS

Inability of client to remain still during the procedure
Improper tourniquet or dye injection technique
INDICATIONS FOR LOWER EXTREMITY
ANGIOGRAPHY

Determining the presence of a tumor compressing the arterial or venous system, causing obstruction
Diagnosing athero-occlusive disease in clients
with diabetes mellitus or peripheral arterial
embolus

Determining the effect of thromboangiitis obliterans on the small and medium-sized vessels of
the extremity
Determining the cause of claudication or thrombosis such as popliteal entrapment syndrome,
cystic adventitial disease, or atherosclerotic
disease
Evaluating AV malformation or other congenital
abnormality
Suspected vascular injury to extremity, penetrating and nonpenetrating, that disrupts or occludes
arteries or veins or both
Determining the level of limb amputation caused
by vascular occlusion after frostbite or electrical
injury
Administering thrombolytic agents such as urokinase (Abbokinase)
Identifying and evaluating veins considered for
use in bypass graft surgery48
Evaluating known or unknown deep venous
thrombosis of lower extremity by a defect in
intraluminal filling when ascending venography is
performed
Evaluating deep venous insufficiency or varicose
vein status before vein ligation or stripping
Suspected venous valvular incompetence by
descending venography in the presence of venous
stasis symptoms
CONTRAINDICATIONS

Allergy to iodinated contrast medium, unless

456

SECTION II—Diagnostic

Tests and Procedures

prophylactic medications are administered before
the study
Edema of the extremity if access to the vessel is
not possible
Impaired renal function or bleeding disorder
Poorly controlled hypertension
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
THE PROCEDURE

For arterial studies, the client is placed on the x-ray
table in the supine position. The femoral arterial site
is used for abdominal aortography and lower
extremity arteriography unless occlusive disease
prevents its use. Alternative sites are the axillary or
the brachial artery. The site is anesthetized by local
injection, and the catheter is advanced into the distal
abdominal aorta under fluoroscopic guidance. A
specified amount of contrast medium is injected at a
calculated rate and period of time. Step-table filming
is performed that includes three films at the level of
the pelvis, then two films at the level of the thighs,
four films of the knees, and then six films at the level
of the calf. Further filming of the distal vessels of the
ankle and foot can be performed in clients with
diabetes mellitus, ulcers, or gangrene. This method
of filming can be complemented with digital
subtraction angiography to perform complete lower
extremity studies by filling in areas of special interest or to examine lower extremities separately in
obese clients. Warming of the feet and legs by application of external heat, use of an occlusive cuff on
the thigh, and intra-arterial injection of a vasodilator such as tolazoline (Priscoline) or dilute nitroglycerin can be administered immediately before the
filming to enhance distal vascular opacification.49
Ascending phlebography or descending venography can be performed for deep venous thrombosis
or venous incompetence as a basis for the study. For
lower limb ascending phlebography, the client is
placed on a tilting table in a supine position. The
dorsum of the foot of the extremity to be examined
is cleansed and the table tilted in a semiupright position that allows more complete filling of the vein.
Weight bearing is allowed on the foot not being
examined to allow for optimal relaxation of the
extremity that is prepared for the study. A superficial
vein is catheterized and the contrast material is
injected slowly after preparation of the site. The flow
is monitored by fluoroscopic visualization. A tourniquet can be placed above the ankle and the knee to
encourage the dye to flow into the deeper veins, if

policy allows this technique. After the injection, spot
films are taken in various views over the thigh, calf,
knee, and also the foot, if a study of this area is
desired. Supine venography can be performed in
clients who cannot be maintained in the semiupright position. This position requires that tourniquets be used and that contrast medium be
administered by continuous infusion rather than by
manual injection. In either position, a cutdown to
expose a vein for cannulation can be performed if
one cannot be used for a superficial injection of the
dye.50
For lower limb descending venography, the client
is placed on the x-ray table in a supine position. The
site can be an arm vein or a femoral vein from the
side opposite the one to be examined. After preparation of the site, the vein is cannulated and the
contrast medium is injected. The dye can also be
injected directly into the femoral vein of the side to
be examined via a needle or catheter. After the injection, the reflux of the dye is viewed by fluoroscopy
and graded from 0 to 5, indicating absence of reflux
to reflux at the level of the ankle. The examination is
performed with the table tilted to the upright position or in the horizontal position while the client
performs Valsalva’s maneuver. At the conclusion of
the study, the client is returned to the horizontal
position.51
At the completion of any of the procedures, the
needle or catheter is removed, and pressure is
applied to the site. A pressure dressing is applied and
taped in place.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any angiographic procedure (see section
under “Cardiac Angiography”).
If a cutdown is performed, inform the client of
the need and the time to have the sutures removed
and to report any redness, swelling, or pain at the
site.
REFERENCES
1. Thomas, CL (ed): Taber’s Cyclopedic Medical Dictionary, ed 19. FA
Davis, Philadelphia, 2000, p 106.
2. Berkow, R: The Merck Manual, ed 16. Merck Sharp and Dohme
Research Laboratory, Rahway, NJ, 1992, p 407.
3. Wojtowycz, M: Interventional Radiology and Angiography. Year
Book Medical Publishers, Chicago, 1990, p 10.
4. Ibid, pp 12–13.
5. Ibid, pp 15–16.
6. Corbett, JV: Laboratory Tests and Diagnostic Procedures with
Nursing Diagnoses, ed 3. Appleton & Lange, Norwalk, Conn, 1992,
p 528.
7. Wojtowycz, op cit, pp 12–13.
8. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed 4.
JB Lippincott, Philadelphia, 1992, pp 678–679.
9. Wojtowycz, op cit, pp 19–20.
10. Ibid, p 18.

CHAPTER 18—Radiologic

11. Pagana, KD, and Pagana, TJ: Mosby’s Diagnostic and Laboratory
Test Reference. Mosby–Year Book, St Louis, 1992, p 153.
12. Fischbach, op cit, p 901.
13. Wojtowycz, op cit, pp 2, 10.
14. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 927.
15. Pagana and Pagana, op cit, p 5.
16. Ibid, pp 5, 8.
17. Ibid, pp 5–10.
18. Ibid, p 166.
19. Nurse’s Reference Library, op cit, p 927.
20. Corbett, op cit, pp 527–528.
21. Wojtowycz, op cit, pp 241–242.
22. Ibid, pp 242–245.
23. Ibid, p 128.
24. Ibid, p 128.
25. Ibid, p 83.
26. Ibid, pp 65–66.
27. Ibid, pp 65–66, 77, 83–84.
28. Ibid, pp 66, 88–91.
29. Ibid, pp 49–50.
30. Ibid, pp 49–50.

31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.

Angiography Studies

Nurse’s Reference Library, op cit, p 979.
Ibid, pp 976–980.
Ibid, p 840.
Wojtowycz, op cit, pp 109–112.
Ibid, p 101.
Ibid, p 571.
Nurse’s Reference Library, op cit, p 573.
Fischbach, op cit, pp 878–879.
Wojtowycz, op cit, pp 267–268.
Ibid, p 265.
Ibid, pp 266–267.
Ibid, p 268.
Fischbach, op cit, p 666.
Wojtowycz, op cit, pp 133–134, 138.
Ibid, pp 134–135.
Ibid, p 135.
Ibid, p 25.
Ibid, pp 26, 227.
Ibid, p 135.
Ibid, pp 228–232.
Ibid, p 235.

457

CHAPTER

Ultrasound Studies
PROCEDURES COVERED
Echocardiography, 460
Echoencephalography, 462
Transesophageal Echocardiography, 463
Ocular Ultrasonography, 463
Thyroid/Parathyroid Ultrasonography, 464
Thoracic Ultrasonography, 465
Lymph Nodes/Retroperitoneal
Ultrasonography, 466
Abdominal/Aortic Ultrasonography, 466
Spleen Ultrasonography, 468
Pancreatic Ultrasonography, 468
Liver/Biliary System Ultrasonography, 469

INTRODUCTION

Kidney Ultrasonography, 470
Bladder Ultrasonography, 471
Prostate Ultrasonography, 472
Scrotal Ultrasonography, 473
Breast Ultrasonography, 473
Pelvic Ultrasonography, 474
Obstetric Ultrasonography, 475
Arterial Doppler Extremity Studies, 477
Arterial Doppler Carotid Studies, 478
Arterial Doppler Transcranial Studies, 479
Venous Doppler Extremity Studies, 480

Ultrasound is a noninvasive instrumentation procedure that uses sound
waves in the frequency range of 20,000 to 10 billion cycles per second, a sound range beyond
that audible to the human ear, to obtain diagnostic information or to perform therapeutic
protocols.1 One cycle per second is equal to 1 hertz (Hz), the unit of measure used to identify
the frequency of sound waves. These high-frequency waves are directed into internal tissues of
the body and reflected back to a transducer. They are then electronically processed and appear
as images on a display screen or oscilloscope for immediate visualization; they are also transformed into audible sounds. The speed of the waves depends on the density and elasticity of the
structures as the waves pass through, resulting in differences that depend on tissue abnormalities. The time it takes sound waves to reach the tissue and return to the transducer is recorded
on film, moving chart, videotape, or digital recording medium for a permanent record of the
study.2 The recording is known as an echogram or sonogram; these terms are used interchangeably with ultrasound studies.
Techniques to display the echo wave image include A and B modes. The A mode presents the
information in a graphic form as in an echocardiogram or echoencephalogram. The B mode
presents the information in varying intensities of brightness by the use of dots that coalesce to
form an anatomic outline as in fetal, pancreatic, kidney, spleen, and bladder sonograms. Realtime scanning uses a multiple transducer to display rapid sequencing of motion that resembles
a movie. It allows imaging of a moving fetus, the motion of the heart, and the movement
involved with larger blood vessels.3 The presence of fluid provides an excellent medium for
transmission of the waves to organs or other areas to be visualized.
The diagnostic value of ultrasound studies is in the ability of the sound waves of varying
intensities to outline the shape and position of organs and tissues of the body and the ability to
detect pathology such as masses, edema, stones, and displacement of adjacent tissues. These
458

CHAPTER 19—Ultrasound

Studies

459

abilities are possible because abnormal tissue is of a different density and elasticity than is the
normal tissue in the same area. Because ultrasonography can be performed quickly, it is
frequently used when time is important. It is limited as a useful diagnostic method in studies
of bones or of air- or gas-filled organs such as the lungs or intestines. Because of this limitation,
portions of the body with these organs situated between the beam and the study site render the
ultrasound procedure ineffective and inconclusive.4 Depending on pathological findings
revealed with ultrasound, more invasive studies such as radiology or radionuclide scanning can
follow to further clarify and diagnose abnormalities.
Ultrasound studies are performed on inpatients and outpatients in the hospital, physician’s
office, or medical imaging agency in a specially equipped room. A skilled technician usually
performs the procedure to ensure satisfactory studies, and a radiologist with special education
and expertise interprets the findings. No anesthesia is needed because no pain is experienced
during ultrasonography. Signed informed consent forms are not required for these studies
unless accompanied by fine-needle biopsy.
The ultrasound procedure is also used therapeutically in frequencies at least 20 times higher
than those used for diagnostic studies. They are delivered in a continuous manner when
performing the therapy and generate heat that treats the pain associated with low back pain
syndrome and that destroys malignant tumor cells.5

DOPPLER ULTRASOUND
TECHNIQUE
The Doppler method encompasses techniques that
transform sound waves into audible sounds heard
with the use of earphones. The sound waves are
produced when the ultrasound beam is passed
through an area of moving blood or fluid to a receiving transducer that amplifies the sounds heard
as pulsations (Fig. 19–1). Varying frequencies result
from the effect of the sound waves on the different
movements of blood or fluid. These pulsating structures can also be displayed as wave motion or
forms on a screen and recorded. The technique
allows assessment of blood flow through arteries
and veins by the monitoring of pulses or sounds
in clients with chronic perfusion problems. The
sounds vary with the patency of the vessel being
examined.
The Doppler technique combined with real-time
imaging is known as duplex scanning. It provides
flow imaging (Doppler) and vessel function (in real
time) to diagnose the presence of aneurysms, plaque
formation in arteries, and thromboses in veins or to
evaluate the rejection of a kidney transplant.6
The Doppler ultrasound also allows assessment of
blood flow through heart valves as in Doppler
echocardiography and for the evaluation of patency
of recent arterial grafts. In critical situations, the
techniques can be used to monitor shock states by
obtaining serial blood readings when accurate audible readings are not possible. Doppler ultrasound
studies on extremities require a normal extremity to

use for comparison readings and calculation of the
pressure index.
The monitoring of fetal heart tones can be
accomplished with the Doppler stethoscope, and the
monitoring of the fetus during labor and birth can
be accomplished with a technique that uses a transducer and a Doppler instrument. This technique is
also used to obtain and monitor blood pressure
readings in infants and small children who are
acutely ill. This is made possible by the instrument’s
ability to translate changes in ultrasound frequencies
to audible sounds via a transducer in the blood pressure cuff.
Color-flow Doppler imaging uses the colors red
and blue to assist in the detection of blood-flow
direction and characteristics of blood-flow velocity
of specific vessels such as fetal, heart, peripheral,
abdominal, and cerebral.7 The use of color is also
effective in accentuating the imaging of blood
shunting found in congenital heart defects or in
visualizing valvular regurgitation.
Doppler procedures are easily performed on
hospitalized clients in an ultrasound vascular room
or at the bedside with portable instruments to monitor circulatory competency or to diagnose abnormalities in those too ill to be transported to the
laboratory. They are also performed on an outpatient basis in hospitals or medical imaging centers.

ULTRASOUND RISKS
There is no evidence at this time to indicate that ultrasound is harmful if given at the appropriate low-

460

SECTION II—Diagnostic

Tests and Procedures

Figure 19–1. Doppler ultrasound device to detect blood flow velocity.

intensity doses. It is a noninvasive procedure unrelated to x-ray studies; thus, there is no exposure to
radiation or use of contrast-mediated materials. The
greatest known risks to tissues associated with these
studies are the production of heat that occurs when
the level of waves exceeds the maximum frequency
recommended for diagnostic procedures. These
higher frequencies are reserved for the therapeutic
destruction of bacteria or tumor cells and require an
ultrasound instrument designed to deliver this level
for a calculated period. Ultrasound diagnostic
equipment is designed to deliver a safe level of
energy that prevents this known risk. The use of
Doppler monitoring of a fetus has been an acceptable practice, but the use of the ultrasound technique for arterial studies produces some heat in
tissues and is considered to be damaging to a fetus.8

ULTRASOUND PROCEDURES
Ultrasound procedures are named for the organ or
region of the body to be examined. Among them are
the liver, pancreas, heart, brain, and almost all other
organs; vessels such as the aorta; or an entire region
consisting of several organs, such as the abdomen or
pelvis. Depending on the region or organ to be studied, the transducer or probe is placed in various
positions, angles, and rotations. Client position also
varies with the site to be studied and includes
supine, prone, sitting, semierect, left lateral, and
right or left oblique. Scanning is performed in two
planes before any images are taken, and all films are

made in at least two scanning planes. The planes
available for scanning include the sagittal, transverse, and coronal.9

ECHOCARDIOGRAPHY
Echocardiography is an ultrasound study performed
to assist in the diagnosis of cardiovascular disorders.
It allows visualization of the internal cardiac structures for size, shape, position, and movement. All
four valves, both ventricles, and the left atrium,
as well as the velocity of the blood flow, can be examined during the movement of the transducer over
the chest.10 Electrocardiography (ECG) and phonocardiography can be conducted simultaneously to
correlate the findings with the cardiac cycle.11
Included in the study are the M-mode method,
which produces a linear tracing of timed motions of
the heart and its structures, and the two-dimensional method, which produces a cross-section
of the structures of the heart and their relationship
to one another as well as changes in the coronary
vasculature. Another method, used to detect
blood-flow pattern and velocity in the heart valves
and great vessels, is color-flow Doppler imaging.
The differences in blue and red hues are
photographed to identify the blood-flow directions
and velocities.12 A combination of these methods is
used to obtain a complete study of the heart and its
structures.
An important consideration in performing
echocardiography is using it in combination with

CHAPTER 19—Ultrasound

other noninvasive tests in the diagnosis of heart
disorders rather than resorting to invasive procedures such as cardiac catheterization and angiography in higher risk clients.
Reference Values
Normal appearance of the size, structures, position, and movements of the heart valves; normal
heart muscle walls of both ventricles, septum,
and left atrium, with adequate blood filling
(Established values for the measurement of
heart activities vary according to physician,
equipment, and agency.)
INTERFERING FACTORS

Inability of client to remain still during the procedure
Obesity, chest thickness, deformity, or other
abnormality or trauma that can increase the
space between the heart and the transducer, which
can affect transmission of waves to and from the
chest
Chronic obstructive pulmonary disease (COPD)
or use of mechanical ventilation that can increase
the air between the heart and chest wall (hyperinflation), which attenuates the ultrasound waves
Dysrhythmias that can affect the test results
Incorrect placement and movement of the transducer over the proper sites or lack of skill in
performing the procedure
INDICATIONS FOR ECHOCARDIOGRAPHY

Detecting and determining the severity of mitral
valve abnormalities such as torn chordae, stenosis,
prolapse, regurgitation, or failure of valve closure
revealed by restriction of valve leaflet motion or
displacement of a valve leaflet
Detecting and determining the severity of aortic
valve abnormalities such as stenosis or failure of
valve closure revealed by regurgitation and valve
thickening
Diagnosing subaortic stenosis revealed by the
displacement of the anterior atrial leaflet and a
reduction in aortic valve flow based on the
obstruction
Diagnosing pulmonary hypertension and pulmonary valve stenosis revealed by echo changes at the
pulmonary valve site
Diagnosing cardiomyopathy associated with
cardiac chamber wall defects revealed by large- or
small-sized chamber internal dimensions and wall
thickness measurements that are less or more
than should be expected

Studies

461

Diagnosing cardiac tumors revealed by echoes in
the vicinity of the mitral or tricuspid valves
Determining the presence of pericardial effusion
revealed by an absence of echoes between the left
ventricular epicardium and pericardium and
caused by fluid between these membranes
Determining the extent of coronary artery disease
revealed by the absence of or abnormal ventricular wall movements resulting from infarction or
ischemia
Detecting ventricular or atrial mural thrombi and
evaluating wall motion after myocardial infarction
In infants and children, diagnosing congenital
heart defects such as ventricular or atrial septal
defect, pulmonary or aortic stenosis, coarctation
of the aorta, patent ductus arteriosus, transposition of the great vessels, hypoplastic ventricles,
tetralogy of Fallot, truncus arteriosus, and other
cardiac malpositions and anomalies
Determining congestive heart failure revealed by
an enlarged chamber size
Detecting changes in valve motion after rheumatic fever exacerbations in children
Detecting direction of blood flow and changes in
velocity of the flow (Doppler echocardiography)
by imaging of the great vessels and right-to-left
shunting of blood in children with congenital
heart defects
Determining the dimensions for the root of the
aorta to detect the true and false lumens in aortic
dissection
Determining the cause of unexplained chest pain,
ECG changes, and abnormal chest x-ray (enlarged
cardiac silhouette)
Evaluating or monitoring prosthetic valve function13
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure takes about 30 to 45 minutes
That there are no food or fluid restrictions before
the study
That the client will be placed in appropriate positions and requested to remain still, turn, or sit up
during the procedure
That a gel substance will be applied to the skin of
the area to be viewed and a device placed and
rotated over the area
That a picture is produced on a screen that the
client can see, if desired
That no pain or risk of complications is associated
with the procedure
Prepare for the procedure:
Obtain a history of previous or existing cardiac

462

SECTION II—Diagnostic

Tests and Procedures

conditions, therapeutic regimen, and results of
related laboratory tests and procedures.
Assist client to remove clothing from the waist up
and provide a hospital gown if client is an outpatient; otherwise, ensure that a hospital gown is
worn with the opening in front.
Obtain vital signs for later comparison readings.
Offer the client an opportunity to void before the
procedure for comfort.
THE PROCEDURE

The client is placed on the examination table in a
supine position. A portion of the chest is exposed
and ECG leads are attached to the chest for simultaneous recording of heart activity during ultrasound.
The client should receive explanations for the use of
ECG. A conductive gel is applied to the chest slightly
to the left of the sternum. The transducer is placed
on the surface of the chest along the left sternal
border, subxiphoid area, suprasternal notch, or
supraclavicular areas to obtain views and tracings
of portions of the heart. The area is scanned by
systematic movement of the probe in a perpendicular position to direct the ultrasound waves to each
part of the heart. The returning echoes are amplified
and displayed on the screen and recorded on a
moving chart strip, film, or videotape.14 To obtain
different views or information about heart function,
the client is placed on the left side and in sitting
positions and requested to breathe slowly, hold
the breath, or perform Valsalva’s maneuver during
the procedure. If the client is requested to inhale
a vasodilator such as amyl nitrite (Vaporole) to identify changes in function of the heart, assessment
is made for side effects such as dizziness or tachycardia. When the study is completed, the leads and gel
are removed from the chest.
NURSING CARE AFTER THE PROCEDURE

Tell the client when the physician will have and
reveal the results, usually 1 to 2 days after the study.

age because the skull has not yet fused into solid
bone mass. Depending on the findings, echoencephalography can be followed by CT and radionuclide scanning.15
Reference Values
Normal position and size of cerebral midline
structures; no third ventricle deviation or
abnormal anatomic position of the right and left
lateral ventricles
INTERFERING FACTORS

Inability of client to remain still and maintain the
head in position, especially if client is a child
Thick hair growth at the test site
Incorrect placement and movement of the transducer over the temporal area of the skull
Jewelry on the neck or ears
INDICATIONS FOR ECHOENCEPHALOGRAPHY

Determining the rate of blood flow in an area
revealed by changes in intracranial pulsations,
distribution patterns, and contours
Suspected cerebral edema, subdural or extradural
hemorrhage revealed by a shift of midline structures of 3 mm or more
Suspected lesions such as tumor or abscess in children revealed by enlarged third ventricle of 7 mm
or more; 10 mm or more in adults
Monitoring hydrocephalus status in infants
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Remove any jewelry and obtain a history that
includes neurological conditions and therapy.
Perform baseline neurological checks for later
comparisons.
THE PROCEDURE

ECHOENCEPHALOGRAPHY
Echoencephalography is an ultrasound study
performed to assist in the diagnosis of abnormalities of the midline cerebral structures that
are associated with pathology, especially the shift
of a ventricle. The procedure has generally been
replaced by computed tomography (CT) in adults
and children because the ultrasound beam is
unable to penetrate the skull bone and is known
to attenuate the echo reverberations within the
skull. It is, however, still an effective diagnostic study
performed on infants and children under 2 years of

The client is placed on the examination table in a
supine position. The head is positioned to the side
on a foam pillow and conductive gel is applied to the
temporoparietal area. Heavy hair growth can be cut
before the study with client or caregiver permission.
The client is requested to lie still during the procedure and, if the client is a small child, the head can
be held in place by an assistant. The transducer is
placed over the area and an ultrasound beam is
directed to the internal structures. As the beam is
converted to impulses, the waveforms that are
produced are visualized on the screen and recorded

CHAPTER 19—Ultrasound

for later viewing. When the study is completed, the
gel is removed from the head.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Perform neurological checks and compare with
baselines if an underlying pathological condition
is known.
Provide a hair shampoo to remove the gel.

TRANSESOPHAGEAL
ECHOCARDIOGRAPHY
Transesophageal echocardiography is an invasive
study performed to assist in the diagnosis of cardiovascular disorders when the noninvasive echocardiography procedure does not reveal the
information necessary to make or confirm a diagnosis. The procedure is usually reserved for use during
surgery or for clients with conditions that can affect
transmission of the waves to and from the chest.16 It
is performed with a small transducer attached to a
gastroscope inserted into the esophagus. The transducer and the ultrasound instrument allow the
beam to be directed to the back of the heart, and the
echoes are amplified and recorded on a screen for
visualization and permanent filming or on a moving
chart paper. A signed informed consent form is
required for this study.
Reference Values
Normal size, position, structures, and movement of the heart valves, muscle walls, and
chamber blood filling
INTERFERING FACTORS

Client agitation or inability to remain still during
the procedure
Incorrect placement and manipulation of the
transducer in the esophagus at the level of the
heart
INDICATIONS FOR TRANSESOPHAGEAL
ECHOCARDIOGRAPHY

Determining cardiac valve and chamber abnormalities when conventional echocardiography
does not produce a clear image, as in obesity,
trauma to the chest or deformity of the chest wall
(barrel chest), and hyperinflation associated with
COPD
Confirming diagnosis if conventional echocardio-

Studies

463

graphy does not explain or correlate with other
clinical or procedural findings
Monitoring cardiac function during open heart
surgery
Diagnosis of esophageal pathology (e.g., varices)
CONTRAINDICATIONS

None, except that the procedure is not performed
on infants or children.
NURSING CARE BEFORE THE PROCEDURE

Client teaching is the same as for esophagogastroduodenoscopy (EGD) (see Chapter 16, “Esophagogastroduodenoscopy” section).
Inform the client that the scope is positioned at
the proper position behind the heart instead of
inserted into the other gastrointestinal organs.
THE PROCEDURE

The client is placed on the examination table in a left
side-lying position. The pharyngeal site is anesthetized, and a bite device is placed in the mouth
to prevent damage to the scope if the client
bites down. The endoscope with the ultrasound
device attached to its tip is inserted 30 to 50 cm
to the posterior portion of the heart as in
any esophagoscopy procedure (see Chapter 16,
“Esophagogastroduodeno-scopy” section). The
depth is determined to achieve the position behind
the heart. The client is requested to swallow to facilitate placement of the tube as the scope is inserted.
When the transducer is in place, the scope is manipulated by controls on the handle to obtain various
views of the heart structure. Scanning is provided in
real-time images of heart motion and recordings of
the images for viewing. Actual scanning is usually
limited to 15 minutes or until the desired number of
image planes are obtained at different depths of the
scope.17 When the study is completed, the scope is
removed and the client is placed in the semi-Fowler’s
position to prevent aspiration until the gag reflex
returns.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for EGD (see Chapter 16, “Esophagogastroduodenoscopy” section).

OCULAR ULTRASONOGRAPHY
Ocular ultrasonography is a study performed to
assist in the diagnosis of abnormalities of the eye
and orbital structures. It is especially useful in identifying pathology in the presence of opacities of the

464

SECTION II—Diagnostic

Tests and Procedures

cornea and lens. The study uses both A- and B-mode
techniques. The A mode converts the echoes into
waveforms that represent the position of different
structures, and the B mode converts the echoes into
a dot pattern that represents a two-dimensional
image of the ocular structures.18 A handheld Bmode scanner is now available for eye ultrasound
that can be performed in the ophthalmologist’s
office.
Reference Values
Normal ocular tissues and structures; no
tumors, lesions, hemorrhage, or retinal or
corneal abnormalities
INTERFERING FACTORS

Inability of client to remain still during the procedure, which can result in an injury
Vitreous humor that has been replaced by gas
Incorrect placement of the transducer on the eye
INDICATIONS FOR OCULAR ULTRASONOGRAPHY

Diagnosing and identifying type, size, shape,
texture, and location of tumors such as melanoma, hemangioma, glioma, neurofibroma,
meningioma, metastic lymphoma
Detecting cystic conditions such as mucoid or
dermoid tumors and differentiating these from
solid tumors
Determining the effect of thyroid disease (Graves’
disease) on eye tissues revealed by inflammatory
changes and extraocular thickening
Diagnosing orbital lesions and differentiating
these from intraocular lesions
Identifying and locating intraocular foreign
bodies
Diagnosing the extent of retinal or choroidal
detachment
Determining vitreous abnormalities such as opacities, vitreous bands, or hemorrhage revealed by
density in image appearance
Evaluating the fundus that is clouded by a cataract
and measuring the length of the eye before
surgery for insertion of a lens implant after
removal of a cataract
Evaluating the eyes for keratoprosthesis
Evaluating the vitreous cavity for abnormalities
before vitrectomy19
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).

Obtain a history that includes known or
suspected eye trauma or abnormalities and therapy or surgery for an eye disorder.
Inform the client that eyedrops will be instilled to
anesthetize the eye for examination and that some
temporary eye blurring will be experienced after
the procedure.
THE PROCEDURE

The client is placed on the examination table in a
supine position. Drops to anesthetize the eye are
instilled according to ordered dosage and frequency
before the study. The client is requested to close the
eye and a conductive gel is applied to the eyelid. The
transducer is placed on the gel, and sound waves are
transmitted into the eye. The waves produce echoes
that are viewed on a screen and photographed for
future comparison and evaluation. This provides a B
scan to diagnose eye abnormalities. An A scan is
performed by placing a cup over the eyeball, applying gel to the cup, and gently moving the transducer
over the cup or gently manipulating the transducer
directly on the corneal surface. The A scan measures
the axial length of the eye and assists in diagnosing
abnormal lesions. The client can be requested to
change the gaze of the eye being examined to obtain
orbital echo patterns that can be differentiated from
abnormal patterns. When the study is completed,
the gel and cup are removed from the eye or eyelid.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Remind the client that vision may be blurred for a
short period and that rubbing the eye should be
avoided until the anesthetic has worn off (about 3
to 4 hours) to prevent injury to the eye.

THYROID/PARATHYROID
ULTRASONOGRAPHY
Thyroid and parathyroid ultrasonography is a study
performed to detect the presence of masses and to
determine the size and weight of the thyroid gland as
well as any enlargement of the parathyroid glands as
a result of pathological processes. It is especially
useful in diagnosing thyroid conditions in pregnant
women because it does not require the use of
radioactive iodine, a substance that can harm the
fetus, to perform other thyroid diagnostic procedures. The use of the study for parathyroid abnormalities is limited because the echo patterns are
lower in amplitude and smaller in size than for
thyroid tissue and are normally indistinguishable

CHAPTER 19—Ultrasound

from the echo patterns of the nearby neurovascular
bundle.20
Reference Values
Normal size, position, and structure of the
thyroid and parathyroid glands, with uniform
echo patterns throughout the glands; no
enlargement, tumor, cysts, or nodules in the
glands
INTERFERING FACTORS

Inability of client to remain still during the study
Incorrect placement and movement of the transducer over the desired test site
INDICATIONS FOR THYROID/PARATHYROID
ULTRASONOGRAPHY

Diagnosing a tumor or solid mass such as benign
adenoma, carcinoma revealed by an irregular
border, shadowing at the distal edge, and peripheral echoes or high- and low-amplitude echoes
Diagnosing cysts revealed by a smoothly outlined
echo-free amplitude except at the far border of the
mass
Differentiating between a nodule and a solid
tumor or a fluid-filled cyst, although small
nodules and lesions can escape detection and
diagnosis
Diagnosing parathyroid enlargement of a tumor
or hyperplasia revealed by echo pattern of lower
amplitude than for thyroid tumor
Determining the size and weight of a mass or the
thyroid gland (Graves’ disease) to evaluate the
effectiveness of a therapeutic regimen
Evaluating thyroid abnormalities during pregnancy, because the procedure does not harm the
fetus
Determining the need for thyroid biopsy of a
tumor or needle biopsy of a cyst
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes the presence of a
palpable mass and therapy or surgery for a
thyroid disorder.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The neck is hyperextended, and a
pillow is placed under the shoulders to maintain the
position and provide comfort. A conductive gel or
oil is applied to the neck and a transducer is placed

Studies

465

on the area and rotated over the entire thyroid site,
including both sides of the trachea. Images are
projected on the screen and photographed for
immediate and future viewing and interpretation or
comparison. For visualization of the anterior
thyroid, a short-focused transducer is used.21 When
the studies are completed, the gel is removed from
the neck and the pillow is removed from under the
shoulders.
Another technique is the placement of a bag of
water hung over the neck area to serve as a transmitter of the waves from the transducer to the thyroid as
the device is positioned over the water bag.22
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).

THORACIC ULTRASONOGRAPHY
Thoracic ultrasonography is a study performed to
assist in the diagnosis of lung abnormalities, especially when other diagnostic procedures are inconclusive in providing information. Because the waves
do not penetrate air, these studies are not considered
useful except when performed to identify conditions
associated with fluid accumulation in the chest. It is
also useful when combined with CT and Doppler
technique to determine the presence of pulmonary
embolism.23 A signed informed consent form is
required if needle aspiration or biopsy is planned.
Reference Values
Normal pulmonary and diaphragm position
and structures; no fluid, lesion, emboli, or infection in the lungs
INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement and movement of the transducer over the desired test sites
INDICATIONS FOR THORACIC ULTRASONOGRAPHY

Determining the presence of pleural effusion
Diagnosing a lesion or abscess if fluid accumulation or consolidation in the lung is revealed by
chest x-ray studies
Determining the cause of acute chest pain
Determining abnormal or malposition of the
diaphragm as a result of a lung disorder
Detecting emboli revealed by echo changes that
indicate anatomic changes in the lung

466

SECTION II—Diagnostic

Tests and Procedures

Guiding needle placement for a pulmonary fineneedle aspiration biopsy in those who are not
candidates for bronchoscopy or who have had a
negative bronchogram
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes chronic pulmonary conditions, therapy, and results of tests and
procedures performed for pulmonary disorders.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The chest is exposed and a conductive gel applied to the area to be scanned. The transducer is manipulated over the entire lung area to
obtain views of the lung(s). Areas that are not filled
with air appear on the screen to reveal lung pathology. When the study is completed, the gel is removed
from the chest.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Needle aspiration site: Note and report changes
in respirations, breath sounds, pneumothorax,
redness, swelling, and pain every hour for 4 hours,
then every 4 hours for 24 hours. Position for
comfort. Change dressing as needed. Administer
analgesic and antibiotic therapy.

LYMPH NODES/RETROPERITONEAL
ULTRASONOGRAPHY
Lymph nodes and retroperitoneal ultrasonography
are studies performed to detect retroperitoneal
pathology, usually lymph node enlargement. It is the
preferred diagnostic method because this area is
inaccessible for conventional radiology in the diagnosis of lymphadenopathy. It can, however, be
performed in combination with lymphangiography
to confirm a diagnosis.
Reference Values
Retroperitoneal and intrapelvic nodes not visible or less than 1.5 cm in diameter
INTERFERING FACTORS

Inability of client to remain still during the
study

Incorrect placement and movement of the transducer over the desired test site
Gas or feces in the bowel that attenuate the sound
waves
INDICATIONS FOR LYMPH NODES/
RETROPERITONEAL ULTRASONOGRAPHY

Suspected lymphoma to diagnose and locate
enlarged aortic and iliac lymph nodes
Determination of visibility and enlargement of
nodes in retroperitoneal solid tumor or infection
Determination of the location of enlarged nodes
to plan radiation and other therapy24
Evaluation of changes in the size of nodes or
tumors during and after therapy revealed by a
shrinkage of the mass or nodes
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Inform the client that food is restricted for 12
hours before the study to minimize bowel motility but that water is permitted.
Obtain a history that includes known or suspected
lymphoma and therapy received to reduce the size
of a retroperitoneal mass or lymph nodes.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The abdomen is exposed from the
umbilicus down and draped for privacy. A conductive gel is applied to the flank and abdominal areas to
be scanned. The transducer is manipulated over the
area, and transverse and longitudinal scans are
taken. Sound waves are echoed to the transducer to
reflect different densities of tissues. These impulses
are displayed on a screen and photographed for
immediate or future viewing and interpretation or
comparison. When the study is completed, the gel is
removed from the area.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”). Inform the
client to resume food intake after the study.

ABDOMINAL/AORTIC
ULTRASONOGRAPHY
Abdominal/aortic ultrasonography is a study performed to assist in the diagnosis of aortic aneurysm
and to determine its size by display of constriction
or dilation of the vessel. Because it is a safe proce-

CHAPTER 19—Ultrasound

dure, it can be repeated as often as every 6 months
to monitor changes in the size of this great vessel.
Ultrasound is performed alone or in combination
with Doppler techniques to identify the vessel lumen
and associated clot formation within an abdominal aortic aneurysm.25 The area scanned includes
the complete abdomen from the umbilicus to the
xiphoid process and includes adjacent organs.
Reference Values
Normal structure of the abdominal organs;
normal contour and normal diameter of the
abdominal aorta of 1.5 to 2.5 cm at various
sections of the vessel

INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement and movement of the transducer over the desired sites
Gas, feces, or barium in the bowel that attenuates
the sound waves
Increased bowel motility that affects sound waves
Obesity that increases space between the organs
and the transducer, affecting the transmission of
waves to and from the abdomen
Scar tissue from previous surgery that prevents
transmission of waves through the skin to the
abdominal organs
INDICATIONS FOR ABDOMINAL/AORTIC
ULTRASONOGRAPHY

Detecting and measuring an aortic aneurysm
within the abdomen for deviations from the
normal diameters at various sections of the vessel
Monitoring aortic aneurysm expansion periodically to prevent rupture revealed by measurements of 7 cm or more in diameter or rapid
increases in size
Determining changes in small aortic aneurysms
before and after abdominal surgical procedures
Differentiating between the vessel lumen and a
clot within an aortic aneurysm with the use of
Doppler technique in combination with ultrasonography
Diagnosing pathology of intra-abdominal organs
such as the liver, spleen, pancreas, gallbladder, and
kidneys, singly or in groups
Determining patency and function of vessels and
ducts such as the portal vein, splenic vein, renal
arteries and veins, superior and inferior mesenteric veins, and biliary and pancreatic ducts

Studies

467

Determining ascites fluid status and the best site
for a diagnostic paracentesis
Diagnosing abdominal pathology during pregnancy, because the fetus is not at risk during ultrasound
Nursing Alert

Sudden changes in vital signs and continuous
abdominal or back pain can indicate an
expanding aneurysm, and sudden onset of
severe pain, hypotension, tachycardia, and
diaphoresis indicate aneurysm rupture. Both
require immediate reporting and interventions.26
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes a suspected or
existing abdominal aortic aneurysm and the
results of the last measurement of aneurysm
diameter to use as a comparison.
Inform the client that food is restricted for 12
hours before the study, but encourage fluids to
provide a full bladder that pushes the bowel out of
the pelvis for scanning.
Administer an enema to remove feces and
barium, and administer simethicone (Mylicon) to
reduce gas from the bowel if ordered.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The abdomen is exposed and
draped for privacy. The client can be requested to lie
on either side or assume a sitting position during the
scanning. A conductive gel is applied to the abdominal scanning sites. The transducer is rotated and
manipulated over the abdomen, avoiding any scar
tissue, from the xiphoid process to the aortic bifurcation and to the left and right of the midline. This
process provides scanning of the aorta and other
sites of the abdominal organs and vessels. Impulses
are transmitted from the device to a screen for visual
display and are photographed for future viewing and
comparisons. When the studies are completed, the
gel is removed from the abdomen.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Inform the client that food intake can be resumed.

468

SECTION II—Diagnostic

Tests and Procedures

Increasing size of aneurysm: Note abdominal or
back pain, hypotension, tachycardia, or diaphoresis. Report to physician immediately. Prepare
client for possible surgical intervention.

SPLEEN ULTRASONOGRAPHY
Spleen ultrasonography is a study performed to
assist in the diagnosis of pathology or trauma of this
organ and the surrounding abdominal organs. It
allows a view of the size, shape, and position of the
organ in the upper left quadrant (ULQ) of the
abdomen. Total splenic volume can also be determined by integrating the cross-sectional areas of
ultrasound scans that are obtained at 1-cm intervals.27 Spleen ultrasonography is often performed in
association with CT to obtain diagnostic information.
Reference Values
Normal size, position, and contour of the
spleen; no splenomegaly, trauma, or masses
INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement and movement of the transducer over the test site
Ribs and an aerated left lung that attenuate the
sound waves
Masses near the testing site that displace the
spleen, causing confusion with a splenomegaly
diagnosis28
INDICATIONS FOR SPLEEN ULTRASONOGRAPHY

Determining the size and volume of the spleen in
splenomegaly
Detecting splenic cysts and differentiating them
from solid tumors and determining whether they
are intrasplenic or extrasplenic when the procedure is combined with CT
Detecting subphrenic abscess after splenectomy
Evaluating extent of abdominal trauma and
spleen enlargement or rupture after a recent accident
Differentiating spleen trauma from blood or fluid
accumulation between the splenic capsule and
parenchyma
Evaluating the spleen before splenectomy
performed for thrombocytopenic purpura
Determining late-stage sickle cell disease revealed
by decreased spleen size29
Evaluating the effect of therapy on the progres-

sion or resolution of splenic disease such as with
chemotherapy that should reduce spleen size
Nursing Alert

Presence of acute pain resulting from trauma
to the spleen causes intolerance to the discomfort of the transducer’s being manipulated
over the area, and comfort measures should
be taken to allow performance of the study.
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes any suspected or
existing diseases or trauma involving the spleen
and any therapy administered to treat splenic
disorders.
Acute pain: Note and report type, location, and
severity of pain. Administer analgesic ordered
before the procedure to enhance comfort during
the manipulation of the transducer over the
abdomen.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The abdomen and chest are
exposed and draped for privacy. A conductive gel is
applied to the ULQ of the abdomen, and the transducer is manipulated over the area. Echoes are
received, amplified, and converted into images on a
screen for viewing. The views can be photographed
for future comparisons to evaluate changes in the
size of the organ. When the studies are completed,
the gel is removed from the abdomen.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).

PANCREATIC ULTRASONOGRAPHY
Pancreatic ultrasonography is a study performed to
assist in the diagnosis of pathology that affects the
size, shape, and position of this organ. Anatomic
abnormalities are identified by echo patterns that
vary with densities in the tissue examined. The
procedure can be performed in combination with a
radionuclide scan of the organ for better visualization, or it can be followed by CT and biopsy for
confirmation of a diagnosis. A signed informed
consent form is required if needle biopsy is planned.

CHAPTER 19—Ultrasound

Reference Values
Normal size, contour, and texture of the pancreas;
patency of the pancreatic duct; no inflammation,
masses, or duct obstruction
INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement of the transducer over the
test site
Gas or barium in the bowel or stomach that attenuates the waves
Obesity that increases the space between the
organ and transducer, affecting transmission of
the waves to and from the abdomen
INDICATIONS FOR PANCREATIC
ULTRASONOGRAPHY

Diagnosing pancreatitis revealed by enlargement
and increase in echoes
Diagnosing pancreatic malignancy revealed by a
poorly defined mass in the pancreas that obstructs
the pancreatic duct
Diagnosing pseudocysts revealed by a welldefined mass and absence of echoes from the interior
Detecting anatomic abnormalities as a consequence of pancreatitis
Monitoring the response to therapeutic regimen
administered for tumor
Providing guidance for needle insertion in percutaneous aspiration and needle biopsy of the
pancreas30
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes suspected or existing disorders of the pancreas, results of diagnostic
tests and procedures, and therapy to treat tumor
or inflammation.
Inform the client of food restrictions, which can
vary with the agency or with physician preference.
THE PROCEDURE

The client is placed on the examination table in a
supine position, although the position can be
changed during the study. The abdomen and chest
are exposed and draped for privacy. A conductive
gel is applied to the epigastric region of the abdomen. A transducer is manipulated over the area and
the echoes are converted to electrical impulses that

Studies

469

are displayed on a screen. During the procedure, the
client can be requested to regulate breathing
patterns, hold the breath, or drink water to enhance
the outline of the abdominal organs and improve
visualization of the pancreas.31 The views are
photographed for future comparisons and evaluation. When the study is completed, the gel is
removed from the abdomen.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”). Inform the
client that food intake can be resumed.
Needle aspiration/biopsy site: Note and report
redness, swelling, bleeding, pain at site, and symptoms of peritonitis. Change dressing as needed.
Administer analgesic and antibiotic therapy.

LIVER/BILIARY SYSTEM
ULTRASONOGRAPHY
Liver and biliary system ultrasonography consists of
studies performed to determine the size, shape, and
position of the liver and the gallbladder, located in
the upper right quadrant (URQ) of the abdomen.
Gallbladder ultrasonography is especially helpful
when performed in clients whose gallbladder is
unable to opacify gallstones with oral or intravenous
radiologic studies. Liver ultrasonography can be
performed in combination with a radionuclide scan
(gallium) to obtain information about liver function
as well as about density differences obtained by
ultrasound.32 Other diagnostic studies such as CT
and liver biopsy can confirm ultrasound findings. A
signed informed consent form is required if catheter
insertion or needle aspiration or biopsy is planned.
Reference Values
Normal size, position, and shape of the liver and
gallbladder; patency of the cystic and common
bile ducts; no hepatic cysts, tumors, or duct dilation; no gallbladder constriction, cysts, tumor,
stones, or cystic/common bile duct dilation
INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement of the transducer over the
test site
Gas or barium in the bowel or stomach that attenuates the sound waves, affecting the imaging of
the liver, gallbladder, and biliary system

470

SECTION II—Diagnostic

Tests and Procedures

Ribs that attenuate the sound waves and affect
imaging of the right lobe of the liver
INDICATIONS FOR LIVER/BILIARY SYSTEM
ULTRASONOGRAPHY

Determining the cause of URQ pain
Diagnosing hepatic lesions such as tumor, cyst,
abscess, or cirrhosis revealed by differences in
density and echo pattern changes
Determining the patency and diameter of the
hepatic duct for dilation or obstruction
Determining metastasis to the liver from a
primary lesion in the breast, colon or rectum, or
other abdominal organs
Differentiating between obstructive and nonobstructive jaundice by identifying the cause
Determining the cause of unexplained
hepatomegaly (mass, trauma) and abnormal liver
function tests (increased alkaline phosphatase)
Diagnosing acute or chronic cholecystitis revealed
by an enlarged gallbladder with wall thickening
Determining gallstones within the gallbladder or
biliary ducts revealed by dilation or obstruction,
or both, of the biliary tree or ducts and increased
bilirubin level
Diagnosing gallbladder stones or inflammation if
oral cholecystography is inconclusive
Diagnosing cysts, polyps, or solid tumor of the
gallbladder revealed by echoes specific to tissue
density and sharply or poorly defined masses
Evaluating therapy for tumor revealed by a
decrease in size of the organ
Guiding catheter placement into the gallbladder
for stone dissolution and gallbladder fragmentation
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes liver or gallbladder
disorders and therapy to treat a tumor or obstruction.
Administer an enema before the study, if ordered,
to remove feces or barium that can interfere with
imaging.
THE PROCEDURE

The client is placed on the examination table in a
supine position, although the prone or side-lying
positions can also be used during the study. The
abdomen is exposed and draped for privacy. The
conductive gel is applied to the skin of the URQ and
the transducer manipulated over the area. During
the procedure, the client is requested to hold the

breath on inspiration as patterns are displayed on a
screen and photographed for future viewing. Several
planes of scanning are obtained. Each lobe and
border of the liver and border of the gallbladder is
examined. The cystic and common bile ducts are
examined for patency. Gallbladder contractibility to
expel the bile stored within it can be achieved with
the administration of a fatty substance (Lipomul) to
allow examination of the organ’s function.33 When
the studies are completed, the gel is removed from
the abdomen.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”). Inform the
client that food intake can be resumed.
Catheter/needle insertion site: Note and report
pain, redness, and swelling every hour for 4 hours,
then every 4 hours for 24 hours. Position on right
side. Change dressing as needed. Administer analgesic and antibiotic therapy.

KIDNEY ULTRASONOGRAPHY
Kidney ultrasonography is a study performed to
assist in the diagnosis of abnormalities that can
be identified by changes in size, structure, or position of either or both organs. The procedure is especially valuable in clients with renal failure because
the study does not rely on renal function and in
clients with hypersensitivity to iodinated contrast
media because none is needed in this diagnostic
method. The study can be performed in combination with other urologic tests such as a radionuclide scan to provide a diagnosis. It can also be
performed after intravenous pyelography to provide
a differential diagnosis in the presence of renal
masses.34 A signed informed consent form is
required if tube insertion or needle biopsy is
planned.
Reference Values
Normal size, position, shape, and structure of the
kidneys; no masses, calculi, inflammation, or
hydronephrosis
INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement of the transducer over the
test sites
Barium remaining in the tract after x-ray studies

CHAPTER 19—Ultrasound

INDICATIONS FOR KIDNEY ULTRASONOGRAPHY

Detecting the size and location of a renal mass in
those who are unable to have an IVP because of
poor renal function or allergy to iodinated
contrast media
Detecting masses and differentiating between
cysts and solid tumor revealed by the specific
sound waveform patterns or absence of sound
waves
Diagnosing the presence and location of renal or
ureteral calculi and obstruction
Determining the size, shape, and position of a
nonfunctioning kidney
Determining an accumulation of fluid in the
kidney, resulting from a backflow of urine,
hemorrhage, or perirenal fluid or blood collection
Diagnosing hydronephrosis in one or both
kidneys, polycystic kidneys, or other congenital
anomalies of the organs in children
Monitoring children for changes in the size of
the kidneys as a congenital renal disease
progresses
Diagnosing effect of chronic glomerulonephritis
and end-stage chronic renal failure on the
kidneys, such as a progressive decrease in size
Evaluating renal transplantation for changes in
kidney size
Locating the site and guiding percutaneous renal
biopsy, aspiration needle or nephrostomy tube
insertion
Evaluating or planning therapy for renal tumor
such as radiation or chemotherapy
NURSING CARE BEFORE THE PROCEDURE

The client is placed on the examination table in a
supine position, although a side-lying position can
be used. A child can be held in the proper position,
if necessary. The area is draped and a conductive gel
applied. The transducer is rotated and manipulated
over the area as the sound waves are transmitted to
the organ, bounced back to the transducer, and
projected onto a screen for viewing. The client can
be requested to breathe as deeply as possible to
obtain views of the upper portions of the kidneys.
When the studies are completed, the gel is removed
from the area.

Studies

471

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study are the same as
those for any ultrasound procedure (see section
under “Echocardiography”).
Tube or needle biopsy/aspiration site: Note and
report redness, swelling, pain at site, and patency
of tube, if inserted; position for comfort; change
dressing as needed; administer analgesic and
antibiotic therapy.

BLADDER ULTRASONOGRAPHY
Bladder ultrasonography is a study performed to
visualize the size and contour of the bladder by
providing an outline of the organ while it is full of
urine. Abnormal contour changes or distortion of
bladder position is an indication of pathology of the
pelvic organs or bladder wall. The procedure can be
performed with ultrasonography of the kidneys,
ureters, bladder, urethra, and gonads to diagnose
renal/urologic disorders.35
Reference Values
Normal size, position, and contour of the
urinary bladder; no masses or urinary residual
INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement of the transducer over the
test site
Barium or gas in the bowel or small amount of
residual urine in the bladder
INDICATIONS FOR BLADDER ULTRASONOGRAPHY

Assessing residual urine after voiding to diagnose
urinary tract obstruction
Detecting tumor of the bladder wall or pelvis
revealed by distortion in position or change in
contour of the bladder
Determining bladder malignancy resulting from
an extension of a primary tumor of the ovary or
other pelvic organs
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes any disease or
dysfunction of the urinary bladder, therapy
received, and results of tests and procedures associated with the urinary bladder.
Encourage fluid intake to ensure a full bladder

472

SECTION II—Diagnostic

Tests and Procedures

to enhance imaging of the organs or have client
void immediately before the procedure if residual
volume is to be measured.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The lower abdomen is exposed and
draped for privacy. The bladder is palpated to ensure
that it is full of urine and a conductive gel is applied
to the area. A transducer is manipulated over the
bladder and pelvic sites, and sound waves are
projected onto the screen and photog-raphed for
immediate and future viewing. If the client is to be
examined for residual urine volume, the bladder is
emptied, the procedure repeated, and the volume
calculated. When the study is com-pleted, the gel is
removed from the abdominal sites.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study are the same as
those for any ultrasound procedure (see section
under “Echocardiography”).

PROSTATE ULTRASONOGRAPHY
Prostate or transrectal ultrasonography is a study
performed to assist in the diagnosis of prostatic
malignancy. The procedure is performed in combination with a digital rectal examination. In addition
to the prostate gland, the seminal vesicles and
periprostatic structures are examined. Because of the
high incidence of prostate cancer in men over 55
years of age, this study is undertaken frequently to
identify and locate early-stage small tumors in this
population.36
Reference Values
Normal size, shape, and structure of the prostate
gland; no abnormal urinary pattern, gland
tumor, or hypertrophy

INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement of the transducer or rectal
probe at the test site
Feces or barium in the rectum
INDICATIONS FOR PROSTATE ULTRASONOGRAPHY

Diagnosing prostate abnormalities such as prostatitis, prostatic hypertrophy, or nodules that have
been palpated

Detecting tumor at an early stage revealed by
difference in tissue densities
Assessing location of tumor and direct placement
of radioactive seeds in the treatment of carcinoma
Locating site and serving as a guide for prostate
biopsy
Evaluating results of therapy such as radiation
and chemotherapy revealed by a reduction in
tumor size
Evaluating voiding disorders and changes in
patterns after treatment
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes suspected and
known prostate and urinary elimination conditions, results of tests and procedures associated
with these disorders, and therapy received for
tumor, enlargement, or micturition abnormalities.
Administer an enema, if ordered, to remove
feces or barium from the rectum to ensure clear
imaging.
THE PROCEDURE

The client is placed on the examination table in a left
side-lying position. The knees are flexed and the
rectal area is exposed and draped for privacy. A
manual rectal examination is performed and a
lubricated rectal probe transducer is inserted into
the rectum along the anterior wall at the level of
the prostate gland. The condom covering the probe
is filled with water to provide the necessary medium
between the probe and the prostate gland to allow
transmission of the sound waves. The client is
informed that some discomfort is experienced
when the water-filled probe is inserted. Scanning
is performed as the rectal probe transducer is rotated
and manipulated to obtain the desired views. In
some studies, the bladder is filled with fluid to
assist in exposing the prostate to the sound waves.37
When the study is completed, the probe is removed
and the anus cleansed of the gel and patted dry.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study are the same as
those for any ultrasound procedure (see section
under “Echocardiography”).
Needle biopsy site: Note and report redness,
swelling, and pain at the site. Change dressing
as needed. Administer analgesic and antibiotic
therapy.

CHAPTER 19—Ultrasound

SCROTAL ULTRASONOGRAPHY
Scrotal ultrasonography is a study performed to
assist in the diagnosis of scrotal pathology and
anatomic abnormalities. If indicated in the presence
of scrotal edema, it can be performed in combination with or after radionuclide scan studies for
further clarification of a testicular mass.38
Reference Values
Normal scrotum and normal size, shape, and
structure of the testes; no tumor, abscess, or
other abnormality
INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement of the transducer over the
test site
INDICATIONS FOR SCROTAL ULTRASONOGRAPHY

Determining the cause of chronic scrotal swelling
Clarifying a diagnosis of scrotal or testicular
abnormality or pathology after questionable
results from a radionuclide scan
Diagnosing a mass and differentiating it from
cyst, solid tumor, or abscess revealed by specific
image patterns
Diagnosing a chronic inflammatory condition
such as epididymitis
Determining the existence of a hydrocele, spermatocele, or scrotal hernia before surgery for repair
Diagnosing torsion and associated testicular
infarction
NURSING CARE BEFORE THE PROCEDURE

The client is placed on the examination table in a
supine position. The scrotal area is exposed and
draped for privacy. The penis is lifted upward and
gently taped to the lower part of the abdomen.
Special sensitivity should be displayed for the client
and possible embarrassment during this part of the
procedure. The conductive gel is applied to the skin
of the scrotum and the transducer is manipulated

Studies

473

over all areas. The waves received are converted to
images on the screen to be viewed and
photographed. When the procedure is completed,
the gel is removed from the area and the penis
untaped and returned to its normal position.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study are the same as
those for any ultrasound procedure (see section
under “Echocardiography”).

BREAST ULTRASONOGRAPHY
Breast ultrasonography is a study performed to visualize and record palpable and nonpalpable masses. It
is especially useful in clients with dense or fibrocystic breasts and those with silicone prostheses because
the beam easily penetrates this material. For these
clients, the procedure allows routine examination
that cannot be performed with x-ray mammography. Ultrasonography can also be performed as an
adjunct to or in place of mammography in those
who refuse or should not be exposed to x-ray diagnostic studies, such as pregnant women.
Reference Values
Normal subcutaneous, mammary, and retromammary layers of tissue in both breasts; no
pathologic lesions in either breast
INTERFERING FACTORS

Inability of client to remain in or assume the
necessary positions during the procedure
Incorrect placement and movement of the transducer over the breasts or a particular site on a
breast
Largeness of breasts that cannot be accommodated by selected methods of ultrasound examination
INDICATIONS FOR BREAST ULTRASONOGRAPHY

Monitoring changes in nonpalpable abnormalities viewed on mammography of fibrocystic
breast tissue
Differentiating among breast masses such as cysts,
solid tumor, or other lesions
Early detection of very small tumors in combination with mammography for diagnostic validation
Assessing palpable masses in pregnant women
to avoid exposure to the radiation of x-ray
mammography

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SECTION II—Diagnostic

Tests and Procedures

Evaluating breast abnormalities in women who
refuse or should not be exposed to mammography
Evaluating breasts of women who have breast
augmentation with silicone prostheses, because
more accurate examination can be achieved with
ultrasound as opposed to x-ray beams, which are
absorbed by the implant
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes suspected or
known breast abnormalities or surgeries, risk
status for breast tumor, presence of prostheses,
last menstrual period dates, and past therapy for
breast abnormalities.
Inform the client to avoid use of lotions, bath
powder, or other substances on the skin of the
chest and breasts.
Administer an analgesic before the study if procedure is painful to breasts.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The chest is exposed and draped for
privacy. A warmed conductive gel is applied to the
breasts and the transducer is manipulated over the
skin of one or both breasts. Sound waves are received
and displayed on a screen and photographed. If the
procedure is performed using a tank of warm, chemically prepared water, the client is placed in a prone
position, and each breast is immersed in the tank.
The transducer placed at the bottom of the tank
transmits waves through the water. The waves are
reflected from both breasts, producing echoes that
are displayed as waveforms on a screen and
photographed for future viewing.39 When the study
in completed, the gel is removed and the breasts are
dried.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study are the same as
those for any ultrasound procedure (see section
under “Echocardiography”).

PELVIC ULTRASONOGRAPHY
Pelvic ultrasonography is a study performed to
determine the presence of masses; their sizes and
structure; and the location of other abnormalities
of the ovaries, fallopian tubes, uterus, cervix, and
vagina. The procedure can be performed transabdominally or transvaginally, depending on the

information needed. The transabdominal approach provides a view of the pelvic organs posterior
to the bladder, and the transvaginal approach
provides a method of monitoring ovulation
over a period of days in clients undergoing fertility
assessment.40
Reference Values
Normal size, position, location, and structure of
the ovaries, fallopian tubes, uterus, and vagina;
no masses or inflammatory disease; intrauterine
device (IUD) located in the proper position
within the uterine cavity
INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement of the transducer over the
pelvic area or of the probe within the vagina for
proper examination
Gas in the bowel
Bladder that is not full and does not push the
bowel from the pelvis and the uterus from the
symphysis pubis as needed to view the pelvic
organs
INDICATIONS FOR PELVIC ULTRASONOGRAPHY

Determining masses in the pelvis and differentiating them from cysts or solid tumors revealed by
differences in sound patterns
Determining the mobility of a pelvic mass and
metastasis of a pelvic or other lesion
Detecting ovarian cysts and determining possible
type revealed by the size, outline, and change in
the position of other pelvic organs
Diagnosing pelvic inflammatory disease when
performed in combination with other laboratory
tests
Detecting uterine masses such as fibroids or
adnexal tumor without differentiating between
the two or confirming a diagnosis
Evaluating or planning therapy, including radiation or chemotherapy, of a tumor revealed by a
reduction in mass size
Diagnosing pelvic abscess or peritonitis as a result
of a ruptured appendix or diverticulitis
Determining bleeding into the pelvis as a result of
trauma to the area or fluid (ascites) accumulation
associated with tumor metastasis
Evaluating pathology associated with postmenopausal bleeding
Determining the type and ascertaining the location of an IUD and determining whether the

CHAPTER 19—Ultrasound

device is in its proper position within the uterus
or whether it has perforated the uterus
Monitoring follicular size in association with
fertility studies, to locate follicles and determine
readiness to remove follicles for in vitro transplantation41
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes gynecologic disorders and therapy received for them.
Encourage fluids to ensure a full bladder if a
transabdominal approach is planned.
Inform the client of a planned procedure using a
transvaginal approach.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The lower abdomen is exposed and
draped for privacy. A conductive gel is applied to
the area and a transducer is manipulated over the
skin while the bladder is distended (transabdominally). The full bladder permits the transmission
of the beam and pushes the uterus and bowel out
of their positions to provide a better view of
the structures posterior to the bladder. The sound
waves are received and displayed on a screen
and photographed. If a transvaginal approach is
performed, a covered, lubricated probe is inserted
into the vagina and manipulated as the sound waves
are received and imaged on the screen. This
approach is used in obese clients, because the additional tissue causes a greater distance between
organs and transducer, or in clients with retroversion of the uterus, because sound waves are better
able to reach the organ from the vaginal site. A full
bladder is not necessary for performing the transvaginal procedure. When the study is completed, the
gel is removed from the skin or the probe from the
vagina and the area is cleansed and patted dry, if
needed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Provide the client with an opportunity to void.

OBSTETRIC ULTRASONOGRAPHY
Obstetric ultrasonography is a study performed to
visualize the fetus and placenta and can be
performed as early as the fifth week of gestation. It is

Studies

475

the safest method of examination to determine fetal
size, growth, and position as well as fetal structural
abnormalities. The procedure can also be used in
combination with Doppler monitoring of the fetal
heart or respiratory movements in the detection of
high-risk pregnancy. Because the pregnant uterus is
filled with amniotic fluid, ultrasonography is an
ideal method of evaluating the fetus and placenta
and is safer than procedures with more potential
danger such as radiologic and radionuclide studies.
Uses of obstetric ultrasonography to secure information regarding the fetus vary with the trimester in
which the procedure is performed. The methods of
scanning include the transvaginal technique, which
is used during the first trimester, and the transabdominal technique, which is used during the second
trimester42
Reference Values
Normal fetal age, size, viability, position, and
functional capacities; normal placental size,
position, and structure with adequate volume of
amniotic fluid
INTERFERING FACTORS

Incorrect placement or angulation of the transducer over the test site, depending on the determinations to be made
Air or barium in the bowel
Inability of the sound beam to penetrate to the
site because of client size
Bladder that is not full enough to push the uterus
from the pubic area to provide a better view of the
pregnant uterus
INDICATIONS FOR OBSTETRIC
ULTRASONOGRAPHY

Determining and confirming pregnancy or multiple pregnancies with the number of gestational
sacs in the first trimester, usually by the 4th or 5th
week
Determining fetal heart and body movements
and detecting high-risk pregnancy via fetal
heart and respiratory movements in combination
with Doppler ultrasound or real-time scanning,
usually by the 6th or 7th week for real-time or the
12th week for Doppler
Measuring gestational age and evaluating umbilical artery, uterine artery, and fetal aorta by
Doppler examination to determine intrauterine
fetal growth rate for retardation43
Determining gestational age by uterine size and
measurements of crown–rump length, biparietal
diameter, extremities, head, and other parts of

476

SECTION II—Diagnostic

Tests and Procedures

the anatomy at different phases of fetal development
Determining structural anomalies of the fetus
such as hydrocephalus, myelomeningocele, skeletal defects, renal abnormalities, intestinal atresias,
cardiac defects, and other congenital conditions,
usually at 20th week or later
Detecting fetal death revealed by an absence of
movement and fetal heart tones
Determining the cause of bleeding, as in placenta
previa or abruptio placentae
Possibly determining gender of fetus
Determining placental size, location, and site of
implantation
Monitoring placental growth and amniotic fluid
volume
Diagnosing fetal abnormalities to prepare for
surgical correction or pregnancy termination
Determining position of the fetus before birth,
such as breech or transverse presentations
Determining effect of Rh incompatibility on the
fetus, as in fetal hydrops
Guiding the needle during amniocentesis and
fetal transfusion
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes menstrual dates;
medications taken for fertility, birth control, or
other reasons; previous pregnancies and complications; treatments received for high-risk-status
pregnancy; and results of tests and procedures
associated with pregnancy.
Encourage fluids or provide fluids 1 hour before
the study to retain a full bladder.
Reassure the client that this study is not harmful
to the fetus because it does not involve radiation.
Provide special support for anxiety that arises
about concern for a normal fetus.
Inform the client that the screen will be in full
view and explanations will be given about the
fetus as it appears. Inform the client if a transvaginal approach is planned.
THE PROCEDURE

The client is placed on the examination table in a
supine position. Attention is given to a hypotensive
and faintness response from pressure on the vena
cava in this position, and the client is repositioned
on the left side to relieve this pressure. The lower
abdomen is exposed and draped for privacy. The
conductive gel is applied to the abdomen and the
transducer is manipulated over the entire abdomen

or lower abdomen, depending on the size of the
uterus. The examination uses both A- and B-mode
techniques that convert echoes into waveforms that
represent the positions of structures, and twodimensional or cross-sectional images are displayed
on the screen and photographed for future viewing.
Real-time imaging reveals the fetus in motion on
the screen. The scanning is performed while the
bladder is full for visualization of the uterus and its
contents. If a transvaginal approach is used, a
full bladder is not needed, and this method is not
used past the first trimester (see “Pelvic Ultrasonography”). When the study is completed, the gel is
removed from the skin or the probe is removed from
the vagina and the area cleansed and patted dry, if
needed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Provide the client with an opportunity to void.
Abnormal procedure results, complications, and
precautions: Provide special support and sensitivity to the expectant mother’s feelings and her
ability to deal with findings that reveal fetal
abnormalities.

DOPPLER PROCEDURES
Doppler ultrasound techniques are described at the
beginning of this chapter. Aside from their main
focus of identifying and locating peripheral venous
and arterial occlusive disease, specific Doppler techniques are also valuable in the study of blood vessels
of the cerebrovascular system (Table 19–1). These
techniques detect extracranial cerebrovascular
disease in clients with diabetes, hypertension with a
risk for stroke, or a cardiac condition. They are also
used to study abdominal and fetal blood vessels. The
testing method most commonly used is duplex scanning, which permits measurement of blood-flow
direction and velocity by combining real-time
imaging with Doppler flow spectrum analyses. This
and other types of noninvasive arterial and venous
diagnostic procedures are performed before an
invasive procedure such as angiography, which
provides information regarding vascular patency.44
Plethysmography is a technique that uses blood
pressure cuffs and a pulse volume recorder and can
be performed instead of or after Doppler ultrasound
to diagnose arterial and venous occlusion or
obstruction. There are no contraindications to these
diagnostic studies or complications associated with
their use.

CHAPTER 19—Ultrasound

TABLE 19–1

Studies

477

Overview of Doppler Ultrasound Studies

Area Examined

Method/Modalities

Findings

Peripheral arterial vessels

Duplex scanning

Arterial stenosis and occlusion

Doppler examination

Peripheral arteriosclerotic occlusive disease

Peripheral venous vessels

Duplex scanning

Venous obstruction

Intracranial vessels

Doppler examination

Arterial spasms or stenosis, arteriovenous
malformation

Carotid vessels

Duplex scanning

Plaques or stenosis and occlusion

ARTERIAL DOPPLER EXTREMITY
STUDIES
Arterial Doppler ultrasound is a technique performed to obtain diagnostic information about the
arterial vasculature of the upper and lower extremities. The swishing, pulsatile, and multiphasic sounds
produced by an artery are audible with earphones.
Changes in these sounds indicate an abnormal flow
and vessel patency alteration and assist in determining partial or complete obstruction of arterial circulation in an extremity. Tests conducted in association
with the Doppler technique to detect peripheral
arterial disease include the treadmill exercise study
to measure ankle pressure before and after exercise,
the reactive hyperemia study to measure ankle pressure before and after application of a thigh cuff,
duplex scanning to measure blood-flow direction
and arterial patency through imaging and waveform
analysis, the limb pressure index study to measure
leg and arm pressures for comparison (anklebrachial index), and the examination of extremities
for multiphasic signals to assist in identification of
the presence, location, and extent of disease. The
measurement of ankle-brachial index is the most
common study performed to evaluate lower extremity arterial circulation.45 Plethysmography can also
be performed to determine volume changes in digital arteries revealed by decreased pressure in a toe or
finger when compared with the ankle (see Chapter
22, “Plethysmography” section).
Reference Values
Normal Doppler signals and pressure readings;
no partial or complete arterial occlusion

Smoking before the procedure, which can
constrict vessels
Arterial occlusion proximal to the test site that
affects blood flow to the area
INDICATIONS FOR ARTERIAL DOPPLER
EXTREMITY STUDIES

Detecting arterial stenosis causing occlusion in an
extremity
Diagnosing arteriosclerosis obliterans and monitoring degree of arterial insufficiency and tissue
ischemia, graded as mild, moderate, or severe
Detecting arterial spasms present in Raynaud’s
phenomenon
Determining arterial occlusive disease of the small
arteries in diabetes mellitus
Determining whether an occlusion is the result of
an embolism
Determining arterial damage after trauma to a site
Determining the presence or absence of collateral
circulation
Diagnosing abdominal aortic aneurysm
Determining the presence and size of aneurysms
or dilations in an extremity
Assessing initial and continuing patency of an
arterial graft
Assessing abdominal arteries after renal transplantation in determining possible rejection
Monitoring effectiveness of therapeutic interventions revealed by progression or maintenance of
the status of an arterial disease graded as deteriorated, improved, or maintained
Determining whether further diagnostic procedures such as angiography are needed to confirm
a diagnosis
NURSING CARE BEFORE THE PROCEDURE

INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement of the transducer over the
desired test sites

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Obtain a history that includes vascular signs and
symptoms, known or suspected vascular disor-

478

SECTION II—Diagnostic

Tests and Procedures

Nursing Alert

The procedure cannot be performed successfully on an extremity that appears pale,
waxen, or cyanotic and is cold to the touch
because these signs indicate severely impaired
circulation.46
ders, and procedures or therapy, or both, administered for vascular conditions.
Advise the client to refrain from smoking for at
least 30 minutes before the study.
Advise the client that blood pressure cuffs are
placed at various sites on the arms or legs to
perform the study.
Administer an ordered analgesic to clients experiencing pain from severe ischemia.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The arms and legs are positioned
and exposed, depending on the limbs to be studied.
The client is reminded to remain very still to ensure
accurate measurements during the procedure.
Blood pressure cuffs are applied to the calf and
ankle and the systolic pressure is measured by noting
the first sound with the Doppler transducer and
comparing it with the brachial pressure. This
comparison determines the presence and location of
peripheral arteriosclerotic occlusive disease, because
a decrease in blood pressure of more than 20 mm Hg
in the arm as compared with the leg indicates an
occlusion proximal to the tested site in the leg. Also,
the ankle pressure divided by the brachial pressure
equals the ankle-to-brachial-pressure index, indicating arterial obstruction if the index is less than
0.96.47
To perform the study, blood pressure cuffs are
placed at the thigh, calf, and ankle of a lower extremity or at the forearm and upper arm of an upper
extremity. A conductive gel is applied to the arterial
sites distal to the cuffs, that is, the femoral, popliteal,
tibial, or dorsalis pedis arteries of the legs or the
brachial, radial, ulnar, or digital arteries of the
arms.48 The most proximal cuff is inflated to a level
higher than the systolic reading noted in the normal
limb, and the Doppler transducer is placed in
contact with the conductive gel distal to the cuff. The
procedure requires a normal extremity for comparison. The cuff is then slowly released while the examiner notes the highest pressure at which the
characteristic swishing sound of the blood flow is
heard. This reading is recorded as the blood pressure
of that artery. The study continues with recordings

of the blood pressure of the arteries at each level.49
The studies performed on the upper extremity are
made with the client in a sitting or supine position
and the arm in hyperextension and hyperabduction
to determine whether compression affects blood
flow.50 When the studies are completed, the cuffs
and conductive gel are removed from the extremities.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Gangrene or ulcerations: Note and report pain
level, tissue breakdown, and condition of skin
on extremities. Administer ordered analgesics.
Change dressings as needed. Protect limb from
trauma or pressure. Avoid leg elevation, and
support limb during movement.51

ARTERIAL DOPPLER CAROTID STUDIES
Arterial Doppler carotid ultrasound is a technique
performed to obtain information about the carotid
arteries using duplex scanning. It provides measurement of the amplitude and waveform of the carotid
pulse with a two-dimensional image of the artery.
The result is visualization of the artery to diagnose
stenosis or atherosclerotic occlusion affecting the
flow of blood to the brain.52 Depending on the
degree of stenosis causing a reduction in vessel
diameter, oculoplethysmography, a pressure measurement, can be performed to determine the effect
of stenosis on the hemodynamic status of the
artery (see Chapter 22, “Oculoplethysmography”
section).53
Reference Values
Normal blood flow through carotid arteries; no
plaque or stenosis indicating occlusive disease
INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement of the transducer over the
desired test site
Abnormally large neck that makes direct examination difficult
INDICATIONS FOR ARTERIAL DOPPLER
CAROTID STUDIES

Detecting plaque or stenosis of carotid artery

CHAPTER 19—Ultrasound

revealed by turbulent blood flow or changes in
Doppler signals, indicating occlusion
Detecting irregularities in the structure of the
carotid arteries
Diagnosing carotid artery occlusive disease
revealed by visualization of blood-flow disruption
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
THE PROCEDURE

The client is placed on the examination table in a
supine position. The neck is exposed and the head
supported to prevent movement. The client is
reminded to remain very still during the procedure
and to not turn the head. A conductive gel is applied
to the skin of the neck at the carotid artery site. The
transducer is placed over the site and moved slowly
in the area of the common carotid artery to the
bifurcation and then to areas of the internal and
external carotids. Duplex scanning provides images
of the blood flow and measurement of the waveform
of the carotid pulse. A reduction in vessel diameter
of more than 16 percent indicates stenosis. When the
studies are completed, the gel is removed from the
sites.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Transient ischemic attack: Note and report
neurological symptoms such as dizziness,
syncope, or blurred vision. Protect from injury if
symptoms occur. Administer or resume ordered
medication regimen.

ARTERIAL DOPPLER TRANSCRANIAL
STUDIES
Arterial Doppler transcranial ultrasound is a technique performed to obtain information about cerebral vessel patency and blood viscosity. The study
measures and records the velocity of blood traveling
through a vessel via a transducer that transmits
waves through a section of the cranium that is thin
or that contains a gap or opening. The procedure
provides valuable information that once could be
obtained only by the more invasive angiography
procedure to assist in the diagnosis and treatment of
neurological and cerebrovascular disorders.54

Studies

479

Reference Values
Normal blood flow through cranial arteries; no
stenosis, hyperemia, arteriovenous (AV) malformation, or increased intracranial pressure
INTERFERING FACTORS

Inability of client to remain still and maintain the
head position during the procedure
Incorrect placement of the transducer over the
site of the skull
INDICATIONS FOR ARTERIAL DOPPLER
TRANSCRANIAL STUDIES

Detecting arterial stenosis or AV malformation in
the cerebrovascular system revealed by low wave
pulsations caused by low flow resistance
Determining the presence of intracranial collateral pathways
Diagnosing hyperemia caused by head injury or
congestion in the tissue surrounding an ischemic
area revealed by a higher velocity and wave pulsations
Determining vertebral or basilar arterial insufficiency
Monitoring increased intracranial pressure
revealed by high wave pulsations
Monitoring vasospasms revealed by changes in
cerebral blood flow
Confirming brain death55
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
THE PROCEDURE

The client is placed on the examination table in a
supine position. The head is positioned to expose
the site and supported to prevent movement. These
sites include the transtemporal (at the temporal site)
to view the middle, anterior, or posterior cerebral
arteries and the circle of Willis; the transorbital (over
the eye) to view the circle of Willis; and the transoccipital (at the foramen magnum) to view the vertebral and basilar arteries. The client is reminded to
remain still and to not move the head.
A conductive gel is applied to the skin of the
site and the transducer placed over it and gently
manipulated around the area. Sound waves are
transmitted through the transducer to the site and
bounced off the cerebral vessel back to the probe; the
waves are then bounced back to the monitor to be

480

SECTION II—Diagnostic

Tests and Procedures

disp-layed as a wave on a screen and permanently
recorded by computer. Normal velocity ranges are
30 to 50 cm per second in posterior arteries and 40
to 70 cm per second in middle and anterior arteries.56 When the studies are completed, the gel is
removed from the site.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Perform vital signs and neurological checks to
compare with baseline as needed.
Neurological changes: Note and report dizziness,
headache, syncope, or visual disturbances. Assist
client to position of comfort. Monitor vital signs
and neurological status for changes from baselines. Administer or resume ordered medication
regimen.

VENOUS DOPPLER EXTREMITY
STUDIES
Venous Doppler ultrasound is a technique
performed to obtain information about the patency
of the venous vasculature in the upper and lower
extremities. The sounds produced by the movement
of the red blood cells in a vein are of a swishing quality that occurs with spontaneous respirations.
Changes in these sounds during respiration indicate
a possible abnormal venous flow in the presence of
occlusive disease; an absence of sounds indicates
complete obstruction. Plethysmography can be
performed to determine the filling time of calf veins
in the diagnosis of a thrombotic disorder of a major
vein and to identify incompetent valves in the
venous system (see Chapter 22, “Plethysmography”
section).57
Reference Values
Normal venous blood flow; no venous occlusion
or obstruction, vascular insufficiency, or vascular injury
INTERFERING FACTORS

Inability of client to remain still during the procedure
Incorrect placement of the transducer over the
desired test sites
Cold extremities resulting in vasoconstriction

Occlusion proximal to the site, affecting blood
flow to the test area
INDICATIONS FOR VENOUS DOPPLER
EXTREMITY STUDIES

Detecting chronic venous insufficiency revealed
by a reverse blood flow, indicating incompetent
valves
Diagnosing superficial or deep venous thrombosis
that leads to venous occlusion or obstruction
revealed by the absence of flow, variations in flow
during respiration, or the absence of flow upon
compression of the extremity
Determining source of emboli when pulmonary
embolism is suspected or diagnosed
Determining venous damage after trauma to the
area
Differentiating between primary and secondary
varicose veins
Determining whether further diagnostic procedures such as angiography are needed to make or
confirm a diagnosis
Monitoring effectiveness of therapeutic interventions (medical and surgical) in the treatment of
venous abnormalities
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
THE PROCEDURE

The client is placed on the examination table in a
supine position. The arms or legs are exposed,
depending on the limbs to be tested. The client is
reminded to remain very still during the procedure
and to breathe normally.
A conductive gel is applied to the skin at the
vein sites. Sites include the femoral, popliteal, and
tibial veins of the legs and the jugular, axillary,
and brachial veins of the neck or arms.58 The transducer is placed over the venous site and the waveforms visualized and recorded with variations in
respirations. Recordings are also made after limb
compression performed proximally or distally to
an obstruction or proximally to the transducer to
obtain information about venous occlusion or
obstruction. Normally, the distal compression or
release of proximal limb compression increases the
speed of blood flow.59 The procedure can be
performed for both arms and legs to obtain bilateral
blood flow determinations. When the studies are

CHAPTER 19—Ultrasound

completed, the conductive gel is removed from the
test sites.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those for any ultrasound procedure (see
section under “Echocardiography”).
Venous stasis or ulcer: Note and report any lesion
that is open or draining, skin discolorations, or
other abnormalities. Maintain clean, dry dressings
to ulcer. Protect limb from trauma. Avoid allowing transducer to be placed on ulcer site.
REFERENCES
1. Thomas, CL (ed): Taber’s Cyclopedic Medical Dictionary, ed 18. FA
Davis, Philadelphia, 1997, p 2025.
2. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed 4.
JB Lippincott, Philadelphia, 1992, pp 767–768.
3. Corbett, JV: Laboratory Tests and Diagnostic Procedures with
Nursing Diagnoses, ed 3. Appleton & Lange, Norwalk, Conn, 1992,
p 575.
4. Fischbach, op cit, p 768.
5. Corbett, op cit, p 574.
6. Ibid, pp 576–577.
7. Fischbach, op cit, p 768.
8. Corbett, op cit, p 576.
9. Tempkin, BB: Ultrasound Scanning: Principles and Protocols. WB
Saunders, Philadelphia, 1993, pp 3, 12–15.
10. Berkow, R (ed): The Merck Manual, ed 16. Merck Sharp and
Dohme Research Laboratories, Rahway, NJ, 1992, p 388.
11. Corbett, op cit, p 581.
12. Pagana, KD, and Pagana, TJ: Mosby’s Diagnostic and Laboratory
Test Reference. Mosby–Year Book, St. Louis, 1992, p 281.
13. Berkow, op cit, p 389.
14. Ibid, p 369.
15. Fischbach, op cit, p 906.
16. Berkow, op cit, p 1390.
17. Fischbach, op cit, p 906.

Studies

481

18. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 577.
19. Ibid, pp 795–796.
20. Springhouse Corporation: Nurse’s Ready Reference: Diagnostic
Tests. Springhouse, Springhouse, Pa, 1991, p 486.
21. Nurse’s Reference Library, op cit, p 541.
22. Fischbach, op cit, p 791.
23. Corbett, op cit, p 583.
24. Nurse’s Ready Reference, op cit, p 479.
25. Berkow, op cit, p 569.
26. Ibid, p 474.
27. Ibid, p 1261.
28. Nurse’s Reference Library, op cit, p 860.
29. Fischbach, op cit, p 790.
30. Ibid, p 784.
31. Ibid, p 784.
32. Ibid, p 870.
33. Ibid, p 787.
34. Ibid, p 782.
35. Berkow, op cit, p 1659.
36. Nurse’s Ready Reference, op cit, p 488.
37. Ibid, p 488.
38. Fishcbach, op cit, p 800.
39. Ibid, p 799.
40. Ibid, p 779–780.
41. Ibid, p 779.
42. Ibid, pp 773–775.
43. Ibid, p 776.
44. Ibid, pp 907–909.
45. Ibid, pp 909–910.
46. Ibid, p 911.
47. Pagana and Pagana, op cit, p 278.
48. Nurse’s Reference Library, op cit, p 914.
49. Pagana and Pagana, op cit, p 279.
50. Nurse’s Reference Library, op cit, p 915.
51. Fischbach, op cit, p 912.
52. Pagana and Pagana, op cit, p 164.
53. Fischbach, op cit, p 916.
54. Nurse’s Ready Reference, op cit, p 487.
55. Ibid, p 487.
56. Ibid, p 487.
57. Fischbach, op cit, p 913.
58. Nurse’s Reference Library, op cit, pp 913–915.
59. Fischbach, op cit, p 908.

CHAPTER

Nuclear Scan and
Laboratory Studies
PROCEDURES COVERED
Brain Scanning, 487
Cerebrospinal Fluid Flow Scanning, 489
Parotid/Salivary Gland Scanning, 490
Bone and Joint Scanning, 490
Bone Marrow Scanning, 492
Adrenal Scanning, 493
Pheochromocytoma Scanning, 494
Cardiac Scanning, 495
Lung Scanning (Ventilation-Perfusion
Scanning), 498
Thyroid Scanning, 500
Parathyroid Scanning, 501
Abscess/Inflammatory Scanning, 501
Gastric Emptying Scanning, 502
Gastrointestinal Reflux Scanning, 503
Gastrointestinal Bleeding Scanning, 504
Meckel’s Diverticulum Scanning, 505

INTRODUCTION

Pancreas Scanning, 506
Liver Scanning, 507
Spleen Scanning, 508
Deep Vein Scanning, 508
Gallbladder/Biliary System Scanning, 509
Kidney/Renography Scanning, 510
Scrotal Scanning, 512
Gallium 67 Scanning, 513
Iodine 131 Scanning, 514
Positron Emission Tomography, 514
Total Blood Volume Study, 516
Red Blood Cell Survival Time Study, 517
Platelet Survival Time Study, 520
Radioactive Iodine Uptake Study, 521
Thyroid-Stimulating Hormone Study, 523
Thyroid Cytomel/Perchlorate Suppression
Studies, 523
Schilling Test, 525

Nuclear scan studies are procedures that use radiopharmaceuticals
(radionuclides in compounds that permit entry into body tissues), radiation detectors with
imaging devices, and computers to visualize organs and study the dynamic processes that differentiate normal from pathological tissues. They are commonly referred to as computed tomography (CT) scanning; however, some CT scans do not use radiopharmaceuticals (see Chapter
21). These diagnostic studies provide more physiological information than the structural types
of information gained from radiologic studies. They can be used to complement x-ray procedures or can be used exclusively to study an organ such as the thyroid gland that has no comparable x-ray procedure.1 Nuclear studies do provide clinical information with a much lower dose
of radiation than x-ray procedures and are much less expensive than other imaging procedures,
such as magnetic resonance imaging (MRI). Although nuclear scans are primarily diagnostic
studies, the radionuclides are also administered in therapeutic doses to treat pathological conditions.

482

CHAPTER 20—Nuclear

Scan and Laboratory Studies

Radionuclide scanning studies involve the administration of a radiopharmaceutical intravenously (IV) or orally, depending on the radioactive material selected and the organ to be
studied, followed by the measurement of the radiation emitted. The radionuclide is an
element that has a nucleus that has been made radioactive and that emits radiation as it
decays or disintegrates. Alpha (), beta (), and gamma () rays can be emitted by the radionuclides used in diagnostic studies. -Rays are the least ionizing type, and the electromagnetic
radiation that is emitted is readily detected with the modern equipment used in the scanning
procedure. Each radionuclide decays at a specific rate (half-life) and has a specific spectrum of
-ray energies that allows its identification in tissues. A small amount of produced radiation can
be detected and is known as a tracer dose. This small dose eliminates the risk of physical and
chemical toxicity and allows the studies to be performed on clients with sensitivities to diagnostic materials such as iodine 123 (123I), which is known to cause an allergic reaction in some
people.
The dose used for diagnostic studies is measured in microcuries (Ci) or millicuries (mCi)
to identify the units of radioactivity. These measurements are now being replaced by the
becquerel (Bq). Radiation doses used for therapy are measured in rads (radiation absorbed
doses) to identify the amount of radiation energy absorbed by the tissues. The incorporation
and distribution of a radionuclide into organ tissues depend on the physiological and biochemical properties of an organ and the specific radiopharmaceutical used.2 This tissue specificity
allows distribution of material in specific organs and differentiation between diseased and
normal tissue by its activity (Table 20-1).
After the administration of the radiopharmaceutical, the amount and changing levels of
the substance are detected by scanning with a scintillation camera. This camera is capable of
monitoring the levels of radioactivity in an area and provides imaging and count rate information. The device detects the location and energy of -rays in an organ and feeds the readings
into a computer that converts them into a two-dimensional scan or picture for immediate
viewing. The computers also store the data for later viewing, analysis, and comparison. The
time between the administration of a radiopharmaceutical and the scanning procedure varies
from immediately to hours or days, depending on the radionuclide and the organ to be examined.
The image or scan is printed on a gray scale that reveals varying shades of gray to identify
the distribution of the radionuclide in parts of an organ and is interpreted by a nuclear medicine physician. Dark spots are known as “hot spots” and indicate a greater concentration in the
area. Spots that do not take up the radionuclide are identified by light shaded areas and are
known as “cold spots.”3 The images can also be recorded in color.
The therapeutic use of ionizing radiation derives from its ability to kill cells by penetrating
the targeted cells and depositing energy within them, thereby inhibiting their division and
growth. The specific rad is calculated according to the half-life, type, and energies of the
radioactive emissions; volume and density of the target organ to be exposed to the radiation;
and the half-life of the radionuclide while within the organ.4 The most common therapeutic
uses are in the treatment of malignancies of the thyroid, chest, and abdomen and in hyperthyroid and polycythemia vera conditions.
Nuclear studies can be considered invasive or noninvasive procedures, and therefore a signed
informed consent is required for scanning procedures involving the administration of a radiopharmaceutical according to agency and nuclear department policies. Laboratory tests that use
radiolabeled materials do not usually require a signed consent. Client preparation is similar for
all nuclear studies and focuses on anxiety reduction caused by the beliefs about the effects of
radiation. An explanation of the benefits and risks of performing the study and of the process
of elimination of the radioactive substance by dissipation and via feces and urine can allay this
anxiety. The studies are performed in a special department by physicians specializing in nuclear
medicine and assisted by trained technicians.

483

484

SECTION II—Diagnostic

TABLE 20–1

Tests and Procedures

Radionuclides/Radiopharmaceuticals and Diagnostic
Scanning Uses*

Radionuclide/Radiopharmaceutical

Organ/Study

Technetium 99m (99mTc)
Technetium Tc 99m pertechnetate

Brain—delayed imaging
Cardiac gated blood pool imaging
Thyroid gland
Parathyroid gland
Parotid and salivary glands
Scrotum and contents
Meckel’s diverticulum

Technetium Tc 99m stannous pyrophosphate

Cardiac infarction
Cardiac gated blood pool imaging

Technetium Tc 99m diethylenetriamine pentaacetic
acid (DTPA)

Brain—early imaging
Cerebrospinal fluid flow imaging
Renal glomerular filtration rate and blood flow
imaging

Technetium Tc 99m RBC or albumin

Gastrointestinal bleeding

Technetium Tc 99m sulfur colloid

Gastrointestinal bleeding
Gastric emptying
Gastroesophageal reflux
Esophageal motility
Liver and spleen
Bone marrow

Technetium Tc 99m glucoheptonate

Brain—early imaging
Renal structural defects

Technetium Tc 99m hydroxyethylene

Bone and joint diphosphonate (HEDP)

Technetium Tc 99m methylene diphosphonate
(MDP)

Bone and joint

Technetium Tc 99m albumin (MAA or HAM)

Lung perfusion

Technetium Tc 99m diisopropyl (IDA)

Gallbladder and biliary systems

Technetium Tc 99m dimercaptosuccinic acid
(DMSA)

Renal excretion

Indium 111 (111In)
Indium In 111 diethylenetriamine pentaacetic acid
(DTPA)

CSF flow imaging

Indium In 111 chloride

Bone marrow
Gastric emptying

Indium In 111 WBC

Abscess and inflammatory areas

CHAPTER 20—Nuclear

TABLE 20–1

Scan and Laboratory Studies

485

Radionuclides/Radiopharmaceuticals and Diagnostic
Scanning Uses*

Radionuclide/Radiopharmaceutical
Iodine 131, 123, 125 (131I,

123

Organ/Study

125

Metaiodobenzylguanidine (MIBG) I 131

Thyroid malignancy total body scanning
Pheochromocytoma

Norcholestenol iodomethyl I 131

Adrenal gland

Orthoiodohippurate (OIH) I 131

Renal function

Iodide I 123

Thyroid gland function

Iofetamine I 123

Brain scanning

Fibrinogen I 125

Deep venous thrombosis

Thallium 201 (

201

Tl)

Thallium chloride Tl 201

Cardiac perfusion
Parathyroid gland

Selenium 75 (75Se)
Selenomethionine Se 75

Pancreas

Gallium 67 ( Ga)
Gallium citrate Ga 67

Body imaging for tumor or inflammatory process

Xenon 133 (133Xe)
Xenon Xe 133 gas
Krypton 81m (

81m

Lung ventilation

Kr)

Krypton Kr 81m gas

Lung ventilation

Radionuclides and PET and SPECT Diagnostic
Scanning
Oxygen 15 (15O), nitrogen 13 (13N), carbon 11
(11C), fluorine 18 (18F)

PET scanning

Gallium 67 (67Ga), thallium 201 (201Tl), technetium
99m (99mTc)

SPECT scanning
(Continued on following page)

POSITRON EMISSION
TOMOGRAPHY
Positron emission tomography (PET), also known
as emission computed tomography, is a noninvasive
procedure that combines the tomographic capabilities of computed tomography scanning with the use
of radiopharmaceuticals to provide clinical information about physiological organ function and
structure.5 The physiological organ activities that
are studied include tissue metabolism; structure or
density; and body fluid volume or flow, or both.
These studies involve the IV administration of
tracers tagged with a radioactive isotope designed to
measure biochemical activities. This isotope emits

positrons (positive electrons) as it deteriorates or
decays; the positrons combine with electrons (negative electrons) normally found in specific tissue
cells. The combination then emits -rays that can be
detected by a PET scanner or camera that transmits
the information to a computer.6 The computer
determines the location and distribution of the
radioactivity and translates the emissions as colorcoded images on a screen. The images can be viewed
immediately, and the information and images are
stored for future use.
The radionuclides used for PET are produced by
a cyclotron and are different from those produced
by a nuclear reactor and used in conventional scanning. They have a short half-life and are free of

486

SECTION II—Diagnostic

Tests and Procedures

Radionuclides/Radiopharmaceuticals and Diagnostic
Scanning Uses* (Continued)

TABLE 20–1

Radionuclide/Radiopharmaceutical

Organ/Study

Radionuclides/Radiopharmaceuticals and
Laboratory Diagnostic Testing
Chromium 51 (51Cr)
Chromated Cr 51 sodium

RBC volume and survival time

Chromated Cr 51 albumin

Gastrointestinal protein loss

Cobalt 57 ( Co)
Pernicious anemia

Cyanocobalamin Co 57
131

Iodine 131, 123, 125 (
131

I or

123

125

123

125

Thyroid gland function
Radioassays
Total blood volume

Iodinated I 125 albumin

Plasma volume

* In this table, radionuclides appear in bold italic type and radiopharmaceuticals appear in regular type. For convention throughout the table and this chapter, radionuclides (i.e., radioactive isotopes) appear as the name of the
element and the isotope number, abbreviated after initial mention (e.g., iodine 131 initially, 131I thereafter).
Radiopharmaceuticals appear as the name of the drug containing the radionuclide followed by the element
symbol, the isotope number, and the carrier agent, if one is used. This table includes the most commonly used
pharmaceuticals and does not preclude the use of others for specific studies or laboratory tests.

contaminants.7 Only institutions that have access to
this capability and have a team of professionals and
a facility to accommodate this technology can
perform PET studies because the radionuclide must
be used immediately after its production. The
isotopes used are oxygen 15 (15O), nitrogen 13
(13N), fluorine 18 (18F), and carbon 11 (11C), which
are the main body constituents.
Although PET is more expensive than are conventional nuclear scans, it is becoming a widely used
diagnostic method, especially for analysis of brain
and heart pathology, staging of disease, and determining the effectiveness of therapy protocols.8 It also
has diagnostic value in the study of the function of
other regions or organs of the body through its ability to obtain physiological and biochemical information not possible with other scanning methods.

SINGLE-PHOTON EMISSION
COMPUTED TOMOGRAPHY
Single-photon emission computed tomography
(SPECT) is another imaging method used to scan
organs. It does not need a positron-emitting isotope
as used in PET, but it uses the same isotopes as
conventional nuclear scans, such as gallium 67
(67Ga), thallium 201 (201Tl), and technetium 99m

(99mTc).9 The procedure allows more sensitive and
specific imaging to obtain diagnostic information
because it uses a more advanced gamma camera.
This camera reveals an additional third dimension
of the tissue segment for viewing. Organs commonly
studied by SPECT are the brain, lungs, heart, spleen,
liver, and bones and joints, depending on the
suspected pathology.10

RADIONUCLIDE LABORATORY
STUDIES
Radionuclides can be administered in very small
doses orally or IV and, at a later time, detected in the
body by laboratory testing of blood, urine, and other
body fluids. These tests determine the ability of the
body to absorb the radionuclide by measurement
of the concentration of radioactivity. Glands such
as the thyroid can also be examined for the concentration of radioactivity by determining the ability
of the body to localize the radionuclide as in the
use of iodine radionuclide in thyroid testing.
Radionuclides and laboratory tests are listed in Table
20–1. Scanning is performed in combination with
laboratory testing for some studies.11 Depending on
the test to be conducted, the laboratory, the department of nuclear medicine, and the client or the

CHAPTER 20—Nuclear

hospital staff share responsibility in performing
these studies.
A wide variety of substances can be measured by
the radioimmunoassay studies included in the laboratory section of this book. They include hormones,
proteins, immunoglobulins, carcinogens, antibodies, vitamins, and drugs that are antigenic or that can
be made so by adding them to an antigenic
substance. These tests involve the administration of
a labeled compound that is produced by chemically
binding the radionuclide to another molecule. They
can be labeled to antigens or antibodies because the
assay is based on an antigen-antibody reaction to
detect and measure a substance. This method of testing provides a high level of sensitivity and specificity
in substance detection. Easily measured isotopes
such as iodine 25 (25I), carbon 14 (14C), or cobalt 57
(57Co) are labeled and used in this method. Some
substances are measured in the blood by the tagging
of proteins with radionuclides. Protein-binding
properties are the basis for estimating the amount of
substances such as cortisol, folate, thyroxine, and
vitamin B12 because the radionuclide-labeled
compound competes with existing compounds for
these binding sites. This competition permits the
measurement of the substances that are bound to
the protein, even in minute amounts.12,13

NUCLEAR SCANNING RISKS
The risk of radiation from the diagnostic use of
radionuclides is very small because of the low dosage
and short half-life of the materials used. Most
radionuclides leave the body in 6 to 24 hours; others
can take as long as 8 days. The radiation dose is actually less than that received in x-ray studies. The use
of radionuclides for diagnostic studies does not
require that personnel and others be protected from
the presence of radiation in the client. Specific
precautions, however, are required to protect others
from the radiation in the client if therapeutic doses
are administered, because these doses are much
higher and the radiation that results is about 1000
times more than that from a diagnostic dose.
Agencies that are approved to use radioactive materials for diagnosis, therapy, or research are provided
with standards and guidelines from the government
regulating commissions. These guidelines include
directions to be followed in the handling, storage,
and disposal of radiopharmaceuticals with short and
long half-lives. Also provided are guidelines and
requirements for the care and handling of specimens
collected for testing, procedures to follow to protect
the client and others from radiation, and procedures
for the disposal of body excretions.

Scan and Laboratory Studies

487

Because of the potential effect of radiation on cell
growth if a fetus is exposed to radionuclide material,
pregnant women are not considered candidates for
nuclear scanning procedures. Mothers who are
breast-feeding their babies are generally excluded as
well, but they can be considered for this method of
diagnostic testing with dosages calculated to provide
the maximum results while using a minimum
amount of the radionuclide.14 Children also are not
generally considered candidates for nuclear testing
unless dosage is carefully calculated, although there
are instances when frequent scanning is performed,
such as in bone cancer. The decision to perform
nuclear studies on these groups varies with diagnosis and physicians as they compare the benefits and
risks of using the very low doses for scanning against
more invasive diagnostic procedures.

RADIONUCLIDE-MEDIATED
SCANNING STUDIES
Radionuclide-mediated scanning studies, known as
an “in vivo” diagnostic method, are performed to
measure the amount of a specific radionuclide
distributed in the body or specific organs by scanning and imaging. The studies are named for the
organ or region of the body to be examined or
imaged. The radiopharmaceutical and route used, as
well as the time involved to perform the study, are
specific to the organ studied. Commonly used radiopharmaceuticals and their tissue sites are listed in
Table 20–1. The scanning procedure provides a
picture of the location, shape, size, and functional
disturbances of an organ. Almost all organs can be
scanned for diagnostic information related to the
presence of tumors or other abnormalities.

BRAIN SCANNING
Brain scanning is a nuclear study performed to assist
in diagnosing abnormalities of the brain and cerebral blood flow that are characteristic of pathology.
The radionuclide 99mTc is administered IV as technetium Tc 99m pertechnetate, which requires a
delayed imaging, as technetium Tc 99m diethylenetriamine pentaacetic acid (technetium Tc 99m
DTPA), or as technetium Tc 99m gluceptate, which
allows earlier imaging and increased sensitivity.15
These substances do not cross the blood–brain
barrier to enter the brain because this complex
system prevents materials from being transported
from the blood into the neural tissue. The presence
of disease that can cause a breakdown or disruption
in this protective barrier allows the radionuclide to
cross into and become concentrated in the abnormal

488

SECTION II—Diagnostic

Tests and Procedures

parts of the brain. Scanning provides the location,
size, and shape of an abnormality. Newer lipid-soluble radionuclides that are able to cross an intact
blood–brain barrier are now used to scan and study
the distribution of a tracer dose to evaluate cerebral
perfusion over a period of time. These newer materials allow imaging of the entire brain instead of
areas involving pathology only.16
Brain scanning has generally been replaced by
diagnostic studies such as MRI and CT scanning,
neither of which requires the use of a radionuclide.
Reference Values
Blood–brain barrier intact with no uptake in
flow and static views revealed; no intracranial
pathology indicating a demyelinating disease,
infection or inflammatory disease, atherosclerosis or stenosis, hemorrhage, aneurysm, tumors,
or arteriovenous (AV) malformation
INTERFERING FACTORS

Inability of client to remain still during the procedure, especially if the client is a child
Environmental stimuli such as noise or bright
lights that can affect the distribution of the
radionuclide used in PET or SPECT
INDICATIONS FOR BRAIN SCANNING

Frequent headache, seizure activity, or neurosensory or neuromuscular complaints or symptoms
of unknown etiology
Determination of the cause of cerebrovascular
disease with or without a stroke, such as atherosclerosis, thrombosis, hemorrhage, or stenosis
revealed by decreased uptake of radionuclide
Identification of sites of cerebral ischemia or
infarction with known presence of atherosclerotic
disease
Detection of intracranial masses such as gliomas,
meningiomas, neuromas, cystic lesions, pituitary
adenoma, malignant primary or metastatic
tumors revealed by an increased uptake and irregular distribution of the radionuclide
Diagnosis of the cause of intracranial bleeding as
in a ruptured aneurysm, subdural hematoma
resulting from trauma, or an AV malformation
Diagnosis of infectious diseases such as encephalitis and brain abscess
Diagnosis of demyelinating diseases such as
multiple sclerosis
Determination of whether hydrocephalus in children is surgically treatable or evaluation of shunt
patency postoperatively

Visualization of suture lines in children
Detection of cerebral edema, hematoma, or
contusion after head trauma
Diagnosis of neurological disorders with presenting deficits or symptoms as in dementia, epilepsy,
Parkinson’s disease, Huntington’s chorea, and
Alzheimer’s diseases when studied by PET
Evaluation of the effect of radiation or
chemotherapy on malignant brain tumor
Determination of brain death revealed by an
absence of uptake in the sinus or brain vascular
system
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing
the procedure greatly outweigh the risks to the
fetus
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure takes about 1 hour unless
delayed scanning is planned within hours, requiring the client to return to the department
That a sedative can be administered before the
study to promote relaxation
That a minute amount of radioactive material will
be administered by IV injection and that this does
not cause harm to the client or those in contact
with him or her
That the radioactive material is excreted by the
body, usually in the urine
That scanning will take place immediately after
the injection or at a later time, depending on the
material used, with a machine that moves over the
area to be examined
That a medication to enhance scanning can be
administered before the procedure
That the only discomfort experienced is the injection of the radiopharmaceutical
Prepare for the procedure:
Obtain a history to ascertain last menstrual
period date and possible pregnancy in women of
childbearing age, known and suspected cerebral
disorders, allergy to iodine, assessment information of neurological system, tests and procedures
conducted and results, or therapeutic interventions performed.
Administer any ordered medications such as
potassium iodine to block thyroid uptake of the
radionuclide or potassium chloride to block
choroid plexus uptake if a radionuclide other than
99m
Tc is used.17
Have the client void before the study to prevent
discomfort or interruption.

CHAPTER 20—Nuclear

Scan and Laboratory Studies

THE PROCEDURE

The client is placed on the examining table in a
supine position. If the client is a young child and
unable to lie still, a general anesthetic can be administered. The radiopharmaceutical is administered IV,
and scanning is performed with the scanner moved
back and forth over the head for immediate
computer images. If a SPECT study is performed,
the images are obtained with the client in a supine
position and the scanner rotated around the head.
The client is reminded to lie very still while the scanner is operating. Scanning can be delayed and
performed 30 minutes after the injection, depending
on the radionuclide used. The client’s position is
changed to lateral and prone to obtain anterior,
lateral, and posterior projections. Blood pool images
and flow studies through the arterial, venous, and
capillary phases are anatomically displayed, based on
counts determined from the radioactivity of the
radionuclide. In some instances, initial normal scans
can appear abnormal at a later time. Later delayed
images are obtained in 3 to 4 hours in the anterior,
posterior, lateral, and vertex positions with the head
in flexion. These static views can reveal abnormally
increased uptake in the cortex to identify pathological tissue.

489

Reference Values
Reflux of CSF into the ventricles; no obstruction
of or increase in CSF volume or pressure
INTERFERING FACTORS

Inability of client to remain still during the procedure, especially if the client is a child
INDICATIONS FOR CEREBROSPINAL FLUID
FLOW SCANNING

Diagnosing and differentiating between communicating nonobstructive hydrocephalus or noncommunicating obstructive hydrocephalus in
infants as revealed by reflux into ventricles or
absence of reflux into ventricles, respectively
Evaluating the size of the ventricles with CSF
reflux if an obstruction is present or evaluating
the ability to reabsorb the fluid revealed by an
increased uptake of the radionuclide in the ventricles
Determining spinal masses or lesions
Evaluating preoperatively for shunt type and
placement and postoperatively for shunt patency
and effectiveness
CONTRAINDICATIONS

NURSING CARE AFTER THE PROCEDURE

Advise the client of the time to return for additional imaging, if appropriate.
Inform the client that the radioactive substance is
eliminated from the body within 6 to 24 hours
and that fluid intake should be increased to
encourage this process.
Phlebitis: Note and report redness, pain, and
swelling at the IV site. Elevate arm, and apply
warm compress to the site.

CEREBROSPINAL FLUID FLOW
SCANNING
Cerebrospinal fluid (CSF) flow scanning is a nuclear
study performed to evaluate patency and filling of
the CSF pathways and the reabsorption or leakage of
CSF. It is most commonly used to diagnose surgically treatable hydrocephalus and to evaluate shunt
patency postoperatively. A radiopharmaceutical is
administered by injection into the spinal column via
a lumbar puncture. Radionuclides used are 99mTc or
indium 111 (111In) administered as technetium Tc
99m DTPA or indium In 111 DTPA, which flow with
CSF. Imaging is performed in 1 hour and periodically up to 72 hours after the injection.

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Additional teaching should include information
about the route of the radiopharmaceutical
administration (lumbar puncture) and an explanation of the procedure.
Inform the client that the schedule of delayed
studies may continue up to 3 days and that no
medications are administered before the procedure.
Maintain the client in a supine position after the
lumbar puncture.
THE PROCEDURE

The client is placed flat on the examining table in a
supine position 1 hour after injection of the radiopharmaceutical into the spinal column. A headdown position is also sometimes used. The client is
reminded to lie very still while the scanner is operating. The scanner is moved over the head for imaging
of ventricular flow. Subsequent imaging takes place

490

SECTION II—Diagnostic

Tests and Procedures

in 4, 6, 24, 48, and 72 hours, depending on persistent
reflux. Anterior, posterior, vertex, and lateral views
are made, with client position changed as needed for
the desired projections.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Assess the puncture site for leakage and apply a
small dressing.
Return the client to the hospital room in a prone
position.
Have the client maintain a prone or supine position for 4 to 8 hours after the study.
Lumbar puncture: Note and report changes in
neurological status, increased blood pressure or
temperature, sensory changes in extremities (tingling, numbness), irritability, or headache. Administer ordered analgesic for headache. Perform
neurological checks every 2 to 4 hours for possible
infection or brain or cord damage.

PAROTID/SALIVARY GLAND
SCANNING
Parotid or salivary gland scanning is a nuclear study
performed to assist in diagnosing abnormalities of
secretory function and duct patency of either or
both glands. The radionuclide 99mTc as technetium
Tc 99m pertechnetate is administered IV, and immediate imaging of blood flow, uptake, and secreting
capability is performed. This study is not made,
however, to provide a definitive diagnosis before
surgery.18
Reference Values
Normal size, shape, and position of the glands;
no masses or duct obstruction

Detecting tumors, cysts, or abscesses and differentiating between them and malignant tumors
revealed by smooth or ragged outlines of the
respective masses
Determining duct obstruction commonly seen in
sialadenitis or Sjögren’s syndrome revealed by
decreased uptake of the radionuclide
Diagnosing acute parotitis and other inflammatory processes of the glands revealed by an
increased uptake of the radionuclide19
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
No medications are administered before the
study.
Teaching should include informing the client that
the time to complete the study is usually 1 hour
and that the scanner is positioned over the neck.
Obtain a history of glandular disorders.
THE PROCEDURE

The client is placed in a sitting position and the
radiopharmaceutical is administered IV. The client is
reminded to remain very still during the scanning.
Immediate scanning is performed for 30 minutes in
anterior, posterior, and oblique views for blood-flow
and uptake studies. If information about secretory
function of the glands is desired, the client is
requested to suck on a lemon about three-fourths of
the way through the study to increase gland secretion and cause the gland to empty.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

INTERFERING FACTORS

Inability of client to remain still during the procedure
INDICATIONS FOR PAROTID/SALIVARY GLAND
SCANNING

Determining the cause of pain and swelling in the
gland area
Detecting tumors of the parotid or salivary
glands, such as oncocytoma, Warthin’s tumor, or
mucoepidermoid tumor, revealed by a “hot”
nodule surrounded by radionuclide uptake

BONE AND JOINT SCANNING
Bone and joint scanning is a nuclear study
performed to assist in diagnosing pathological
conditions as well as complications of bone disease.
The advantage of bone scanning over other bone
diagnostic procedures is that abnormalities, or “hot
spots,” appear 3 to 6 months before an x-ray reveals
any pathology. Total body scanning is performed if
metastatic disease to the bone is suspected. Total
body scanning is important because all of the skeleton can reveal different locations of the metastases,

CHAPTER 20—Nuclear

such as the skull, long bones, pelvis, vertebrae, ribs,
and sternum.20
The study is performed after the IV administration of the radionuclide 99mTc as technetium Tc
99m hydroxyethylene diphosphonate (HEDP) or
technetium Tc 99m methylene diphosphonate
(MDP), with scanning, flow studies, and blood pool
studies undertaken immediately or delayed to allow
concentration of the radionuclide in the bones and
joints. Concentration depends on bone metabolism,
which determines the amount of uptake of the
substance, and the blood flow, which increases the
deposition of the material as the flow is increased.
A decrease or absence of blood flow produces “cold”
bone defects. It is the increase of radionuclide
uptake and activity (chemisorption) on the scan
that represents an abnormality because it becomes
concentrated at a higher or lower rate than does
normal bone tissue. There are, however, normal
areas of increased activity in adults, such as the
sternum and the sacroiliac, clavicular, and scapular
joints. In children, normal areas of increased activity are growth centers and cranial sutures.21
Gallium (67Ga) scanning after the administration of
gallium citrate Ga 67 can follow a bone scan to
obtain a more definitive study if acute inflammatory
conditions such as osteomyelitis or septic arthritis
are suspected (see later section titled “Gallium 67
Scanning”).
Reference Values
Normal uptake by chemisorption of radionuclide by the bone; no tumors, infection or
inflammation, fracture, or joint derangement or
joint inflammation

Scan and Laboratory Studies

491

as osteogenic sarcoma, chondrosarcoma, and
Ewing’s sarcoma
Determining metastatic malignant tumor from
primary sites such as breast, lung, thyroid, prostate, or kidney revealed by an increased uptake of
radionuclide
Diagnosing benign tumors or cysts revealed by
minimal or normal uptake, with the exception of
osteoid osteoma, which is revealed by increased
uptake and blood pool activity
Diagnosing osteomyelitis, usually in the femur,
tibia, fibula, and humerus
Determining acute osteomyelitis when performed
with a 67Ga scan
Detecting fractures (traumatic and stress) and
evaluating healing after a fracture, especially when
an underlying bone disease is present
Diagnosing metabolic bone disease and differentiating among osteoporosis, osteomalacia, Paget’s
disease, and bone disorders secondary to hyperparathyroidism
Detecting Legg-Calvé-Perthes disease and determining the phase of the disease in children,
revealed by changes in uptake activity in each
phase
Evaluating prosthetic joints for infection, loosening, dislocation, or breakage revealed by increased
uptake around the prosthesis
Evaluating tumor response to radiation or
chemotherapy
Identifying appropriate site for bone biopsy
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing
the procedure greatly outweigh the risks to the
fetus
NURSING CARE BEFORE THE PROCEDURE

INTERFERING FACTORS

Inability of client to remain still during the procedure, especially if the client is a child
Multiple myeloma or thyroid malignancy causing
false-negative scan for bone abnormalities
INDICATIONS FOR BONE AND JOINT SCANNING

Determining the cause of unexplained bone or
joint pain
Diagnosing degenerative joint changes or septic
arthritis that occurs in arthritic conditions
revealed by increased uptake of radionuclide
Confirming a diagnosis of temporomandibular
joint derangement by SPECT studies
Diagnosing primary malignant bone tumors such

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client of the scanning schedule, which
begins 2 to 4 hours after the injection and then
takes 1 hour to complete.
A history should include assessment information
about the musculoskeletal system and known and
suspected bone diseases.
If a full body scan it to be performed, request that
the client remove all clothing and provide him or
her with a hospital gown.
THE PROCEDURE

The client is placed on the examining table in a
supine position with the site to be scanned exposed.

492

SECTION II—Diagnostic

Tests and Procedures

To conduct a flow study, the radiopharmaceutical is
injected IV, and images are obtained in sequence
every 3 seconds for 1 minute. The client is reminded
or assisted to remain very still during the procedure.
A blood pool image is then obtained over the area.
To improve tumor imaging by allowing the radionuclide to be taken up by the bones, a 2- to 3-hour
delay takes place before static images are made. The
client is requested to drink fluids during this time
and is allowed to walk around or sit and read. Also,
request that the client void before the delayed imaging to prevent interference with examination of the
pelvic bones. After the delay, multiple images are
obtained over the complete skeleton. A large-fieldof-view camera is used to cover the entire area.
Sacral lesions can be imaged by positioning the
client on the hands and knees and using a tail on the
detector.22 After 24 hours, additional views can be
taken of a specific area, which can be useful in evaluating a fracture for repair processes. Total body
imaging is performed primarily to determine
metastatic sites that can be detected long before they
are seen with x-ray radiography. If a SPECT study is
performed for bone and joint imaging, the scanner
is rotated around the client, with various views
taken.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

BONE MARROW SCANNING
Bone marrow scanning is a nuclear study performed
to assist in diagnosing pathological conditions of
active bone marrow in the axial skeleton in adults
and in the full length of extremities in infants, with
a gradual retraction in children until 10 years of age.
The marrow moves peripherally in the long bones as
red blood cell (RBC) production requirements
increase, and this distribution can be detected on the
scan. The degree of bone marrow activity and bone
marrow distribution revealed provides the clinical
information related to pathological processes.23 The
abnormalities seen on the scan include focal defects,
increased size of the liver and spleen, decrease in the
central marrow, peripheral extension, and increased
uptake outside of normal areas (extramedullary
hematopoiesis). Depending on the suspected
pathology, 99mTc administered as technetium Tc
99m sulfur colloid is used when imaging the entire
body about 1 hour after injection, or 111In as indium
In 111 chloride is used when imaging the entire
body 48 hours after injection.

Reference Values
Normal distribution of active marrow in the
axial skeleton; no avascular necrosis, extramedullary hematopoiesis, bone marrow infarcts or
hemolytic anemia, metastatic bone tumor, or
diffuse hematologic disorders
INTERFERING FACTORS

Inability of client to remain still during the procedure
INDICATIONS FOR BONE MARROW SCANNING

Diagnosing avascular necrosis in hip studies
revealed by the absence or decrease of uptake
activity
Determining extramedullary hematopoiesis sites
such as the liver, spleen, lymph nodes, lungs,
kidneys, breasts, or adrenal glands
Diagnosing thalassemia, sickle cell anemia,
hereditary spherocytosis, and myeloproliferative
disorders revealed by an increased uptake of
radionuclide
Diagnosing bone marrow infarcts common
in sickle cell anemia and thalassemia revealed
by “cold” areas with increased uptake in the
surrounding active bone marrow
Detecting metastases of malignant tumor to bone
revealed by focal defects
Diagnosing and determining the stage of diffuse
hematologic disorders such as polycythemia vera,
leukemia, hemolytic anemia, aplastic anemia,
myelofibrosis, Hodgkin’s and non-Hodgkin’s
lymphoma revealed by a decrease or absence of
radionuclide uptake
Evaluating a disparity between marrow histology
and blood smear results to determine errors in
marrow sampling
Determining splenic erythrocytosis before
splenectomy and determining whether enough
active bone marrow is present to allow removal of
the spleen24
Determining bone marrow depression during or
after chemotherapy or radiation therapy
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing
the procedure greatly outweigh the risks to the
fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

CHAPTER 20—Nuclear

Inform the client of the scanning schedule and
explain that the study takes 1 hour.
Obtain a history to include information about
known or suspected hematologic disorders and
other associated tests and procedures performed.
THE PROCEDURE

The client is placed on the examining table in a
supine position and reminded to remain very still
during the scanning procedure. The radiopharmaceutical technetium Tc 99m sulfur colloid is injected
IV, and imaging is begun after 30 minutes to 1 hour.
Scanning of the entire body, both anteriorly and
posteriorly, is performed. Technetium Tc 99m sulfur
colloid is used to examine for avascular necrosis,
bone marrow infarct and hemolytic anemias,
metastatic tumors, and diffuse hematologic disorders. If indium In 111 chloride is injected, imaging is
started in 48 hours, and scanning of the entire body
is performed. This agent is used to examine the
client for extramedullary hematopoiesis and sites of
occurrence.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

ADRENAL SCANNING
Scanning of the adrenal glands is a nuclear study
performed to assist in diagnosing pathology based
on the secretory function of the adrenal cortex. This
function is controlled primarily by the anterior pituitary through the adrenocorticotropic hormone that
stimulates the adrenal cortex to produce cortisone as
well as to secrete aldosterone. High concentrations
of cholesterol, the precursor in the synthesis of
adrenocorticosteroids including aldosterone, are
stored in the adrenal cortex. This storage allows the
radiopharmaceutical norcholestenol iodomethyl I
131 to be used in identifying pathology. The uptake
of this substance occurs gradually and imaging
reveals increased uptake, unilateral or bilateral
uptake, or absence of uptake in the detection of
pathological processes. Suppression studies can be
performed to differentiate the presence of a tumor
from hyperplasia of the glands, followed by prescanning treatment with corticosteroids.25
Reference Values
Normal bilateral secretory function of the adrenal cortex with the uptake of the radionuclide;
no tumors, infection, or secretory suppression

Scan and Laboratory Studies

493

INTERFERING FACTORS

Inability of client to remain still during the
procedure
INDICATIONS FOR ADRENAL SCANNING

Diagnosing Cushing’s syndrome revealed by
increased symmetrical uptake, indicating bilateral
hyperplasia, or asymmetric uptake, indicating
unilateral hyperplasia or adenoma
Determining aldosteronism revealed by asymmetric uptake
Differentiating between asymmetric hyperplasia
and asymmetry from aldosteronism with dexamethasone suppression test
Determining adrenal suppressibility with prescan
administration of corticosteroid to diagnose
and localize adrenal adenoma, aldosteronomas,
androgen excess, or low-renin hypertension
Diagnosing glandular tissue destruction caused
by infection, infarction, neoplasm, or suppression
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing
the procedure greatly outweigh the risks to the
fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client that there will be a prolonged
scanning schedule over a period of days and that
the time to complete each scan is 30 minutes.
Administer supersaturated potassium iodide
(SSKI) 24 hours before the study to prevent
thyroid uptake of the free iodine.
Obtain a history to include information about the
endocrine system, allergy to iodine, laboratory
results for cortisol, and urinary adrenal function
tests.
THE PROCEDURE

The client is placed on the examining table in a
supine or sitting position. The radiopharmaceutical
is injected IV and the client is returned to the hospital room or requested to return to the department in
24 hours, when the scanning procedure will begin.
The client is requested to remain very still in the
prone position and the imaging then takes place for
posterior views for at least 20 minutes. Scanning is
then performed each day for 3 to 5 days after this
first scan. If a suppression test is to be performed, 4
mg of dexamethasone is administered for 7 days
before the scanning procedure.

494

SECTION II—Diagnostic

Tests and Procedures

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Administer supersaturated potassium iodide 10
days after the injection of the radiopharmaceutical to ensure that the iodine is not taken up by the
thyroid gland until the material is entirely
excreted.

PHEOCHROMOCYTOMA SCANNING
Pheochromocytoma scanning is a nuclear study
performed to identify the presence of this tumor in
the body. The tumor arises from the chromaffin cells
of the sympathetic adrenal system, with 90 percent
occurring within the adrenal medulla and 10 percent
in extra-adrenal sites. A higher percentage of the
extramedullary tumor sites occur in children. The
defining characteristic of pheochromocytomas is the
production of excessive catecholamines (epinephrine, norepinephrine) with epinephrine-secreting
tumors found in the intra-adrenal site and norepinephrine-secreting tumors found in the intra-adrenal or extra-adrenal sites. About 10 percent are
malignant, with an increased incidence in the extraadrenal sites.26
The study involves a total body scanning after the
IV injection of iodine 131 (131I) administered as
metaiodobenzylguanidine (MIBG) I 131, composed
of bretylium and guanethidine, which localizes
sympathetic tissue. Imaging is performed primarily
to localize the tumor site rather than to formulate a
diagnosis; the site is revealed by an abnormal uptake
of the radionuclide at the intra-adrenal or extraadrenal sites. Laboratory measurements of catecholamines in the urine and blood are performed to
determine an increased secretion of these substances
and, combined with CT and ultrasonography,
provide definitive diagnostic information. Once
diagnosed, surgical removal of the tumor is the most
effective treatment.27
Reference Values
Normal uptake of radionuclide in all areas of the
body: liver, spleen, urinary bladder, salivary glands, heart, and adrenal glands; no adrenergic
tumor

Barium in the gastrointestinal tract from previous
diagnostic procedures
INDICATIONS FOR PHEOCHROMOCYTOMA
SCANNING

Confirming a diagnosis and localizing an adrenergic tumor when CT has not provided a definitive diagnosis
Identifying extra-adrenal sites of a tumor such as
the organ of Zuckerkandl revealed by increased
uptake
Confirming a suspected tumor in the area of the
adrenal glands revealed by an abnormal uptake of
the radionuclide
Identifying and localizing related tumors such as
neuroblastomas, carcinoid tumors, and paraganglionomas (tumors found outside of the adrenal
medulla)
Diagnosing medullary cancer of the thyroid gland
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing
the procedure greatly outweigh the risks to the
fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Assess for iodine allergy, and note the results of
catecholamine measurement in blood and urine
laboratory tests.
THE PROCEDURE

The client is placed on the examining table in a
supine or sitting position. The radiopharmaceutical
is injected IV and the client is returned to the hospital room or requested to return to the department in
24 hours. The client is requested to remain very still
during the procedure, and imaging of the whole
body is performed at that time and then again in 48
and 72 hours as the radionuclide localizes in the
sympathetic tissues of the body. Renal scanning is
also performed to outline the kidneys. In some
instances, an additional scan takes place 4 days after
the injection. The daily scanning is necessary
because the tumor can be visualized on a specific day
or on all days.
NURSING CARE AFTER THE PROCEDURE

INTERFERING FACTORS

Inability of client to remain still during the procedure

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Administer supersaturated potassium iodide 10

CHAPTER 20—Nuclear

days after the injection of the radiopharmaceutical.

CARDIAC SCANNING
Cardiac scanning is a nuclear study that includes
several categories of procedures depending on the
radionuclide used and the suspected pathology. The
various studies can reveal clinical information about
wall motion (contractions), ejection fraction, coronary blood flow, ventricular size and function,
valvular regurgitation, and cardiac blood shunting.
Contractions are performed by wall motion of the
left ventricle and the movements are graded from 31
(normal) to 0 (akinesis). Blood ejection is
performed by movements of the right ventricle. The
ejection fraction is calculated from the end-diastolic
volume and end-systolic volume in the left ventricle
and equals the percentage of the end-diastolic
volume pumped per beat or contraction. Coronary
blood flow is greatest during diastole because the
vessels are not constricted by a contracting cardiac
muscle at this time; however, the blood flow is
increased with exercise.
Thallium chloride (Tl 201) rest or stress studies
are performed to assist in diagnosing ischemic
cardiac disease, risk for coronary artery disease
(CAD), and myocardial infarct. The radiopharmaceutical is used because it is an analogue of potassium, an element that is normally taken up by heart
muscle and distributed in the myocardium, depending on the blood flow in the muscle. The narrowing
of the coronary vessels affects the blood flow and
uptake of the radionuclide and, because the flow
increases with exercise, significant narrowing can be
detected during stress testing. A reduction in the
uptake is an indication of pathology and appears as
“cold spots” on the image. This procedure is best
suited for clients who are suspected of having CAD
or angina pectoris or who need physiological information about cardiac function but are not able to
undergo invasive procedures such as angiography or
cardiac catheterization.
If stress testing cannot be performed by exercising, dipyridamole (Persantine) can be administered
orally or IV. The drug is a coronary vasodilator and
is administered before thallium chloride Tl 201 and
the scanning procedure. It increases the blood flow
in normal coronary arteries two to three times without exercise and reveals perfusion defects when
blood flow is compromised by vessel pathology. This
study is reserved for clients with lung disease
(chronic obstructive pulmonary disease [COPD]),
neurological disorders (multiple sclerosis or spinal
cord injury [SCI]), and orthopedic disorders
(arthritis or amputation) who are unable to partici-

Scan and Laboratory Studies

495

pate in treadmill, bicycle, or handgrip activities for
stress testing.28 This study carries the risk of angina
or coronary infarction.
Technetium Tc 99m pyrophosphate studies are
performed to diagnose the presence and location of
myocardial infarction. The study is usually made in
combination with electrocardiography (ECG) and
laboratory cardiac enzyme blood tests to provide a
diagnosis. This test depends on the uptake and
concentration of the radionuclide, depending on
blood flow, because the material must reach the
damaged tissue to be taken up. This uptake is found
in abnormal areas of the myocardium, most
commonly the left ventricle. The earliest uptake
occurs 4 hours after coronary artery occlusion, the
peak uptake in 48 hours, and a continuing diminished uptake for 5 to 7 days, depending on the size
and extension of the infarct. Abnormalities are based
on an increased uptake by the myocardium, and
activity is graded from 4 (activity greater than
bone) to 0 (activity less than bone). A wide range of
conditions causes uptake of the radionuclide, and
the delay in producing a definitive myocardial
infarction diagnosis limits this procedure as a useful
tool. Imaging with labeled monoclonal antibodies
achieves a more accurate identification and localization of an infarct site.
Gated blood pool imaging is performed to assist
in diagnosing cardiac abnormalities. The radiopharmaceuticals used for this study are technetium Tc
99m pyrophosphate labeled with RBCs for multiple
gated studies and technetium Tc 99m sulfur colloid
for first-pass studies. Information gained from this
study includes wall motion abnormalities at rest or
with exercise, ejection fraction, ventricular dilation,
unequal stroke volumes, and cardiac output. ECG is
performed and synchronized with the imager and
computer and is termed gated. Multiple gated acquisition imaging (MUGA) is the scanning of the heart
in motion during the cardiac cycle to obtain multiple images of the heart in contraction and relaxation.29 The MUGA procedure is also performed
after administration of nitroglycerin sublingually to
determine its effect on ventricular function. These
studies are less risky to the client than cardiac
catheterization in obtaining information about
heart function.
Reference Values
Normal wall motion, ejection fraction, coronary
blood flow, and ventricular size and function;
no cardiac ischemia, myocardial infarction,
cardiac hypertrophy, akinesia or dyskinesia (wall
motion), or heart chamber disorder

496

SECTION II—Diagnostic

Tests and Procedures

INTERFERING FACTORS

Inability of client to remain still or to assume
different positions during the procedure, especially if the client is a child
Exhaustion that prevents reaching maximum
heart rate
Excessive eating or exercising between initial and
redistribution imaging 4 hours later
Other nuclear scan, such as bone, thyroid, or
lung, performed on the same days as the stress
or gated scans with thallium chloride Tl 201 or
technetium Tc 99m pyrophosphate labeled with
RBCs
Drug therapy that includes sustained-release
nitrates for angina, because such therapy affects
cardiac performance
Chest wall or cardiac trauma, angina that is difficult to control, significant cardiac dysrhythmias,
or recent cardioversion procedure
INDICATIONS FOR CARDIAC SCANNING

Rest or stress scan with thallium chloride Tl 201:
Determination of risk for or diagnosis of CAD
revealed by a decrease or absence of radionuclide uptake
Evaluation of the extent of CAD with the
number of vessels involved and the functional
significance of these abnormalities
Evaluation of site of an old infarction for
obstruction of cardiac muscle perfusion
Assessment of function of collateral coronary
arteries
Determination of rest defects and reperfusion
with delayed imaging in unstable angina
Evaluation of bypass graft patency after surgery
revealed by normal flow studies when
compared with abnormal studies before
surgery
Evaluation of effectiveness of medication regimen and effect of balloon angioplasty on
narrowed coronary arteries
Cardiac myocardial imaging with technetium Tc
99m pyrophosphate:
Diagnosis in the absence of a diagnosis from
ECG and tests for enzyme elevation
Diagnosis or confirmation and location of
acute myocardial infarction revealed by an
increased uptake of the radionuclide in the
infarcted cells
Evaluation of possible reinfarction or extension
of the infarct
Differentiation between recent and past infarction

Obtaining of baseline information about
infarction before open heart surgery
Diagnosis of perioperative myocardial infarction
Detection of possible cardiac toxicity, myocardial contusion or trauma, and pericarditis or
myocarditis
Gated blood pool imaging with technetium Tc
99m pyrophosphate labeled with RBCs or technetium Tc 99m sulfur colloid:
Diagnosis of ischemic CAD revealed by wall
motion abnormalities and fall in ejection fraction during exercise
Diagnosis of myocardial infarction revealed by
regional wall motion abnormalities
Diagnosis of true or false ventricular aneurysm
revealed by paradoxical wall motion, bulge in
the shape of the left ventricle, and site of the
defect
Evaluation of ventricular size and function
after an acute episode or in chronic heart
disease
Diagnosis of valvular heart disease and determination of the optimal time for valve replacement surgery revealed by the degree of
regurgitation
Quantification of cardiac output by calculating
ejection fraction
Determination of cardiomyopathy revealed by
diffuse wall motion abnormalities, decreased
ejection fraction, and dilated left ventricle
Differentiation between COPD and left
ventricular failure revealed by an enlarged right
ventricle, decreased ejection fraction in the
right ventricle, and diffuse hypokinesis
Determination of doxorubicin (Adriamycin)
cardiotoxicity to discontinue the therapy
before congestive heart failure (CHF) develops,
revealed by a reduced ejection fraction and
dilated left ventricle
Detection of left-to-right shunts and determination of the pulmonary-to-systemic bloodflow ratios, especially in children30
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
Stress test not performed in the presence of left
ventricular hypertrophy, right and left bundle
branch block, or hypokalemia, or in those receiving cardiotonic therapy31
Dipyridamole testing not performed in presence
of anginal pain at rest or severe atherosclerotic
coronary vessels

CHAPTER 20—Nuclear

Nursing Alert

Stress testing is terminated if the client develops angina, severe dyspnea, fall in blood pressure, exhaustion, or if significant ischemia or
cardiac dysrhythmias are revealed by ECG.
The use of dipyridamole in testing can precipitate myocardial infarction or angina. IV
aminophylline should be on hand to reverse
the effects of the drug if needed.
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client of the scanning schedule and
explain that the study takes about 30 minutes.
Advise the client that food and fluids are restricted
for 2 to 4 hours, smoking for 4 to 6 hours, and
medications such as theophylline for 24 hours
before the study.
Inform the client that exercising is often
performed during a stress test and that medications may be administered before or during the
test to evaluate heart function but that medications are not part of the routine preparation.
If an ECG is to be performed during the test,
inform the client that electrodes will be attached
to the chest.
Include cardiovascular assessment information
and the client’s medication regimen in the history.
THE PROCEDURE

Rest or Stress Cardiac Scan. For the rest study, the
client is placed in an upright position for 15 minutes
to reduce pulmonary flow before and during the
injection of the radiopharmaceutical. The client is
then placed in a supine position and requested to
remain very still. Imaging by a scanner placed above
the chest begins 20 minutes after the injection to
allow maximum concentration because of a delay at
rest that is caused by slower blood clearance.
Scanning is performed to obtain anterior, left anterior-oblique, and lateral views. For the stress study,
electrodes are applied to the chest, and ECG monitoring is begun; a blood pressure cuff is applied to
the arm to monitor changes during the test. An IV
line is initiated on the arm without the blood pressure cuff to allow access during the exercising.
Exercise is carried out on a treadmill to a maximum
heart rate. Alternatives to the treadmill for those
unable to use it are the bicycle ergometer, isometric
handgrip, or cold pressor (immersion of hand in ice

Scan and Laboratory Studies

497

water) tests. To allow distribution during stress, the
radiopharmaceutical is injected into the line about
60 to 90 seconds before the exercise is to be terminated. With the client in a supine position as in the
rest study, imaging takes place as soon as possible
after exercising, and a computer analysis of the
images is performed. Redistribution imaging can
take place 4 hours after the injection to differentiate
between ischemia (heart function returns to
normal) and infarction (heart function remains
abnormal). For clients unable to exercise, dipyridamole can be administered orally or IV 4 minutes
before the injection of thallium chloride Tl 201.
Cardiac Myocardial Imaging. The client is placed
on the examining table in a supine position and the
radiopharmaceutical injected IV. Scanning is
performed 2 to 4 hours later to obtain anterior left,
left anterior-oblique, and left lateral views.
Gated Blood Pool Imaging. For MUGA studies, the
client is placed at rest in a supine position and the
ECG is attached for use as a reference point of electric and diastole and end systole. The reference
points are to be synchronized with the data collection in frames that are recorded throughout the
cardiac cycle by the computer. The client is
requested to remain still during the scanning. The
radiopharmaceutical is administered IV, and scanning is performed to obtain anterior, left anterioroblique, posterior-oblique, and left lateral views. As
many as 12 to 64 consecutive frames can be
recorded, and the data from each beat of each
cardiac cycle are added to the counts stored in the
frame. Exercise imaging is also possible by taking the
client through graded exercises on a bicycle in a
recumbent position and imaging at each exercise
level and after the exercise. For first-pass studies,
scanning is performed immediately after the injection as the material passes through the right heart, to
the lungs, and then to the left ventricle. Anterior or
right anterior-oblique views are taken. If nitroglycerin is given after a resting multiple gated study, a
scan is performed and another dose of the medication is given, with scanning to follow until the
desired blood pressure level is obtained.
Heart Shunt Imaging. The client is placed on the
examining table in a supine position with the head
slightly elevated. The radiopharmaceutical is
injected into the external jugular vein and immediate scanning is performed. This procedure is
performed in conjunction with a resting multiple
gated acquisition study to obtain the ejection fraction.32

498

SECTION II—Diagnostic

Tests and Procedures

PET or SPECT Imaging. This specialized threedimensional study can be performed if the radiopharmaceutical and a positron camera are available
for PET. SPECT studies can be performed to provide
short axis, vertical long axis, and horizontal long axis
views to obtain a more sensitive study of heart function.33
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Monitor ECG and blood pressure until baselines
have been achieved and maintained.
Remove the electrodes from the sites and cleanse
the areas as needed.
Inform the client of the schedule for prescribed
follow-up exercise plan.
Phlebitis: Note and report redness or swelling at
the IV site. Elevate the arm and apply warm
compresses to the site.
Exercise reactions: Note and report angina, dyspnea, nausea, headache, or exhaustion during the
stress study. Also note and report a fall in blood
pressure, ECG change indicating ischemia or
dysrhythmias, or confusion, pallor, clammy skin,
or unsteady gait. Terminate test early if symptoms
appear.
Dipyridamole administration: This medication
is administered by the physician in attendance for
a stress study, while aminophylline is administered IV to reverse any occurrence of ischemia,
which could cause angina.

LUNG SCANNING (VENTILATIONPERFUSION SCANNING)
Lung scanning, or ventilation-perfusion (V/Q) scanning, is a nuclear study performed to assist in diagnosing acute and chronic pulmonary conditions.
These diseases cause decreased pulmonary blood
flow and hamper air flow and gas exchange, resulting
in a ventilation-perfusion imbalance. A radiopharmaceutical is injected IV or inhaled; scanning is
performed to obtain views of the lungs and evaluate
blood flow or perfusion (perfusion scan) and
patency of the pulmonary airways or ventilation
(ventilation scan). One or both scans are performed
to obtain clinical information that assists in differentiating among the many possible pathological
conditions revealed by the procedure. The scan
results are correlated with other diagnostic studies
such as pulmonary function, chest x-ray, pulmonary
angiography, and arterial blood gases.
Lung perfusion scanning is performed primarily

to diagnose pulmonary embolism, especially when
the chest x-ray is normal. Because blood flow is
restricted in the area of an embolus, perfusion
defects or areas of decrease or absence of activity are
visualized by scanning. The radionuclide 99mTc as
technetium Tc 99m macroaggregated albumin
(MAA) or technetium Tc 99m human albumin
microspheres (HAM) is injected IV and distributed
throughout the pulmonary vasculature, depending
on the gravitational effects of perfusion. Normally,
gravity causes an uneven distribution of blood flow
with a three to five times greater flow volume in the
lower than in the upper regions of the lungs. Many
diseases decrease the pulmonary blood flow, and the
multiple views of areas of visible activity of the
radionuclide assist in the differentiation of these
diseases based on these gravitational effects.34
Lung ventilation scanning is performed with
perfusion scans to provide specific information
about perfusion abnormalities by differentiating
between pulmonary embolism and other pulmonary diseases. Ventilation also is not uniform in the
lungs because of gravity, causing a one to two times
greater intrapleural pressure in the apex than in the
base of the lungs. Abnormalities are visualized by
imaging areas of decreased activity in the lungs after
inhalation of a radionuclide as xenon Xe 133 gas or
krypton Kr 81m gas. The compound is distributed
through the airways with the inspired air. Defects in
regional ventilation are identified as areas not normally well ventilated with regular breathing, based on
the gravitational effect on ventilation. The areas of
decreased activity indicate that the total lung volume
is not ventilated. Diagnosis of COPD and pulmonary embolism is confirmed by perfusion and ventilation studies that reveal a match or mismatch
between perfusion and ventilation. COPD causes a
match of perfusion and ventilation (abnormal ventilation in an area of a perfusion defect), and pulmonary embolism causes a mismatch of perfusion and
ventilation (normal ventilation in an area of diminished perfusion).35
Reference Values
Normal perfusion and ventilation of lungs and
V/Q ratio; no pulmonary embolism, COPD,
tumors, pneumonia, atelectasis, or pulmonary
hypertension
INTERFERING FACTORS

Inability of client to remain still during the procedure or to breathe through a mask for the ventilation study

CHAPTER 20—Nuclear

Improper positioning during the inhalation of the
radiopharmaceutical, because gravity affects the
distribution of the material in the lungs
Other nuclear scans performed on the same day,
which would affect the distribution of the
radionuclide
Conditions that can simulate a perfusion defect
similar to pulmonary embolism, such as emphysema, effusion, or infection, because these conditions affect perfusion or ventilation36
INDICATIONS FOR LUNG SCANNING
(VENTILATION-PERFUSION SCANNING)

Perfusion Study
Diagnosing pulmonary embolism when the chest
x-ray is normal (Pulmonary embolism is revealed
by areas of decreased activity.)
Differentiating between pulmonary embolism
and other pulmonary disease such as pneumonia,
pulmonary effusion, atelectasis, asthma, bronchitis, tumors, and emphysema revealed by a perfusion defect matching an abnormal area on the
chest x-ray
Evaluating perfusion changes associated with
CHF and pulmonary hypertension
Detecting lung displacement by fluid or chest
mass
Detecting malignant tumor of the lung revealed
by perfusion defects resulting from bronchial
obstruction
Evaluating pulmonary function preoperatively in
clients with pulmonary disease
Ventilation Study
Diagnosing COPD revealed by areas of abnormal
ventilation, with washout images and decreased
activity representing defects in regional ventilation in single-breath images
Differentiating between COPD (abnormal ventilation in an area of perfusion defect) and
pulmonary embolism (normal ventilation in an
area of decreased perfusion)
Evaluating pneumonectomy when performed
with a perfusion study to determine the potential
for pulmonary insufficiency
Determining smoke inhalation injury that could
lead to edema, infection, or atelectasis
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing
the procedure greatly outweigh the risks to the
fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the

Scan and Laboratory Studies

499

same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client of the scanning schedule and
explain that the study takes 30 minutes.
Inform the client that a breathing mask is used to
administer the radiopharmaceutical for the ventilation study, and allay anxiety associated with this
procedure.
History should include information about the
pulmonary status, recent x-ray results, and the
determination of whether the client can lie flat or
needs to elevate the head on pillows to facilitate
breathing during the procedure.
THE PROCEDURE

Perfusion Study. The client is placed on the examining table in a supine position. The syringe containing the radiopharmaceutical is shaken to resuspend
the particles, and the material is administered
IV. The client is requested to remain still during the
scanning, and imaging is performed immediately
to obtain anterior, posterior, both lateral, and both
oblique views. Multiple views are the best confirmation of perfusion defects within the lung vasculature.
Ventilation Study. The client is placed in an upright
position with the camera positioned posteriorly. The
client is requested to remain still during the scanning. The mask is positioned over the nose and the
gas containing the radiopharmaceutical is injected
into the intake port of the mask as the client takes a
deep inspiration. Single-breath images are obtained.
After this imaging, the client rebreathes the gas
containing the radiopharmaceutical in a closed
spirometry system for 4 minutes, allowing the gas to
enter the abnormal lung areas. Images are obtained
during and at the end of this procedure. Valves are
then readjusted to allow the client to breathe room
air that washes out the gas. Washout images are
obtained for 6 minutes at 30- to 60-second intervals.
After these images, additional scanning can be
performed in the oblique positions to allow location
of abnormal anteroposterior areas.37 Ventilation
scanning can be performed using krypton Kr 81m
gas on clients unable to perform breathing techniques needed for the study. These images can be
obtained regardless of the timing of perfusion studies; otherwise, ventilation studies are performed
before perfusion studies.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

500

SECTION II—Diagnostic

Tests and Procedures

Ensure ease of breathing by elevating the client’s
head on pillows, if needed.

THYROID SCANNING
Thyroid scanning is a nuclear study performed to
assist in diagnosing thyroid dysfunction and benign
or malignant thyroid tumor. Normally, the thyroid
reveals a homogeneous uptake of the radionuclide;
an absent or diminished uptake is an indication of
pathology. The most frequent indication for thyroid
scanning is the presence of a nodule or enlarged
thyroid gland.
The procedure is performed after an IV injection
of 99mTc administered as technetium Tc 99m
pertechnetate, with imaging taking place in 20
minutes, or an oral ingestion of 123I as iodide I 123,
with imaging in 4 or 24 hours. Iodide I 123 is the
most commonly used radiopharmaceutical because
of its short half-life and lower radiation exposure.
Iodine 131 administered as metaiodobenzylguanidine (MIBG) I 131 is used in scanning for thyroid
cancer and therapy.
The classification of “cold” nodules results from a
decrease or absence of radioactivity in the gland and
suggests a malignant tumor. “Hot” nodules result
from an increase or normal activity in the gland, and
this finding suggests a benign tumor or thyrotoxicosis.38,39 Thyroid scanning with iodide I 123 is usually
performed in combination with a radioactive iodine
uptake study on the same day. Thyroxine (T4) level
is also obtained to diagnose thyroiditis and thyroid
function tests to diagnose Graves’ disease. Thyroid
ultrasound and nodal biopsy can be performed to
confirm a diagnosis.
Reference Values
Normal size, shape, weight, position, and function of the thyroid gland with a homogeneous
uptake of the radiopharmaceutical; no thyroiditis, Graves’ disease, or benign or malignant
tumor
INTERFERING FACTORS

Inability of client to remain still during the procedure
Other recent nuclear scans or radiologic studies
using iodinated media that can affect uptake of
the radionuclide
Dietary intake deficient in iodine content, because
this increases uptake, or intake of foods containing iodine, because this decreases uptake

Vomiting or diarrhea, or both, that can decrease
uptake of the radionuclide
Medications such as thyroid drugs, multivitamins,
steroids, cough medications, thyroid hormone
antagonists, or phenothiazines
INDICATIONS FOR THYROID SCANNING

Assessing palpable nodules and differentiating
these from benign tumor cyst (uptake of radionuclide) and malignant tumor (absence of uptake)
Determining the cause of neck or substernal
masses
Differentiating between Graves’ disease with a
diffuse and enlarged thyroid and Plummer’s
disease with a nodular thyroid, both resulting in
hyperthyroidism
Evaluating thyroid function in hyperthyroidism
and hypothyroidism when analyzed with laboratory thyroid function tests, thyroxine (T4),
triiodothyronine (T3), and thyroid uptake tests
Diagnosing thyroiditis conditions such as acute or
chronic Hashimoto’s thyroiditis revealed by
uptake below or above normal, depending on
disease stage
Determining the thyroid gland as a primary site in
clients with metastatic tumors
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Instruct the client to restrict iodine-containing
foods for 2 to 3 weeks before the procedure.
Inform the client of the scanning schedule and
explain that the procedure takes 30 minutes.
Restrict food and fluids for 2 to 4 hours before the
study, according to policy and physician preference.
History should include medications taken or
withheld before the procedure, previous scans or
radiologic studies, results of laboratory tests, and
foods or medications containing iodine ingested
before the study.
THE PROCEDURE

The client is given iodide I 123 by mouth in a capsule
or technetium Tc 99m pertechnetate by IV injection,
depending on which has been ordered. The client is
placed on the examining table in a supine position,
and imaging is performed 20 minutes after an IV

CHAPTER 20—Nuclear

injection or 2 to 4 hours after an oral dose. The client
is requested to remain still and the scanning camera
is moved over the neck. Additional scanning after
the oral dose can be performed in 24 hours. Counts
per minute are obtained and the percentage of
uptake is calculated, using the dose administered
and the decay factor.40

Scan and Laboratory Studies

501

and adenoma revealed by a larger sized gland in
adenoma
Identifying and locating ectopic glands to prevent
missing a tumor during surgical excision
Contraindications
Pregnancy, unless the benefits of performing
the procedure greatly outweigh the risks to the
fetus

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Resume withheld food, fluid, and medications
after the study.

NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any thyroid nuclear scan study (see
section under “Brain Scanning” and preceding
“Thyroid Scanning” section).
THE PROCEDURE

PARATHYROID SCANNING
Parathyroid scanning is a nuclear study performed
to assist in diagnosing tumors or hyperplasia of the
glands. The main function of the glands is to synthesize, secrete, and store parathyroid hormone, which
regulates the level of calcium and phosphorus in the
blood. Change in these levels indicates hyperparathyroidism. The radionuclide 201Tl as thallium
chloride Tl 201 is administered IV, and scanning is
performed in 20 minutes. This is followed by the
administration of 99mTc as technetium Tc 99m
pertechnetate, and additional scanning is performed. Computer subtraction of images is
performed to complete the study and determine the
amount of the radionuclide concentrated in the
parathyroid glands as opposed to the thyroid gland
(thallium chloride Tl 201 is taken up by normal
thyroid tissue).41
Reference Values
Normal size, position, number, weight, and
function of the parathyroid glands with normal
uptake of the radionuclide in the parathyroid
and thyroid glands, no hyperplasia or adenoma
of the parathyroids
INTERFERING FACTORS

Inability of client to remain still during the procedure
Recent intake of iodine-containing foods or
medications, or recent tests and procedures using
iodinated contrast media
INDICATIONS FOR PARATHYROID SCANNING

Differentiating between parathyroid hyperplasia

The client is placed on the examining table in a
supine position with the neck slightly hyperextended. The client is requested to remain still during
the scanning, and thallium chloride Tl 201 is administered IV. Scanning is performed in 5 to 30 minutes
for mediastinal and neck views. Technetium Tc 99m
pertechnetate is then injected, and scanning is
performed for the same views. Computer subtraction of images is performed by the subtraction of the
99m
Tc imaged in the thyroid from the 201Tl uptake in
the parathyroid glands.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

ABSCESS/INFLAMMATORY SCANNING
Abscess or inflammatory scanning, also known as
leukocyte imaging, is a nuclear study performed to
assist in the diagnosis of inflammatory lesions indicating an infectious process. Abscess detection by
nuclear scanning is performed on clients suspected
of having an abscess but with no localized signs of
infection. Abnormalities are identified by scanning
24 hours after the IV injection of 111In administered
as indium In 111 oxine–labeled leukocytes (WBCs)
that are separated from other components of the
blood. This is followed by the injection of 99mTc
administered as technetium Tc 99m sulfur colloid
and the performance of a liver and spleen scan to
compare with the indium In 111 oxine–labeled
WBC scan. Diagnosis is based on the intensity of
uptake outside of normal organs as compared with
the liver. CT and ultrasonography are performed to
provide a diagnosis in a client with localized signs of
an abscess.42

502

SECTION II—Diagnostic

Tests and Procedures

Reference Values
Absence of uptake of radionuclide outside of
normal organs; no inflammation in the abdomen, lungs, or gastrointestinal tract
INTERFERING FACTORS

Inability of client to remain still during the procedure
Gastrointestinal bleeding caused by ulcers, diverticula, or tumors
Other sites that take up the radionuclide, such as
colostomies, hematomas, postoperative wounds,
or IV catheters
Long-term therapies, such as hemodialysis, hyperalimentation, or steroidal or antibiotic therapy,
which affect the function of the WBCs
INDICATIONS FOR ABSCESS/INFLAMMATORY
SCANNING

Diagnosing abdominal abscess revealed by focal
area of increased uptake that is greater or equal to
the liver
Diagnosing lung infections revealed by focal or
diffuse uptake of the radionuclide (although
uptake can be caused by CHF, aspiration, atelectasis, or pulmonary emboli)
Determining whether an infection is causing an
elevated temperature of unknown origin
Diagnosing infectious disorders of the gastrointestinal tract, such as necrotic bowel, inflammatory bowel disease, or pseudomembranous colitis,
which are revealed by a greater intensity of uptake
Diagnosing inflammatory processes in the
extremities, such as osteomyelitis
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
study greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client of the scanning schedule and
explain that scanning for each radionuclide
administered takes about 1 hour.
History should include signs and symptoms of
any infectious process in any area of the body and
results of recent diagnostic laboratory tests and
procedures.
THE PROCEDURE

The client is placed on the examining table in a
supine position and requested to remain still during

the scanning. The indium In 111 oxine–labeled
WBC is injected IV. The client is returned to or
requested to return to the department in 24 hours
for imaging of the liver, followed by posterior and
anterior imaging of the abdomen, pelvis, and chest.
Extremities can also be imaged, but they require a
longer time to scan. After abscess inflammatory
scanning, technetium Tc 99m sulfur colloid is
injected, and a standard liver scan is obtained. These
scans are compared to determine areas outside the
liver and spleen that concentrate the radionuclide.
This concentration indicates an abnormality and
reveals a 90 percent accuracy for identifying an
abscess/inflammatory site.
The procedure for labeling the WBCs with
indium In 111 oxine is performed on a sample of the
client’s blood or a donor’s blood if the client’s WBC
is low. The WBCs are separated from the blood and
labeled and reinjected into the client. This process
can take up to 3 hours, and the client can wait or be
requested to return for administration of the radiopharmaceutical.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

GASTRIC EMPTYING SCANNING
Gastric emptying scanning is a nuclear study
performed to determine the time it takes for the
stomach to empty itself of foods or fluids. Normally,
solids are emptied by reduction to allow passage
through the pylorus by antral contractions, and
liquids are emptied primarily by gravity. Thus, solids
are more sensitive for use in the detection of abnormal gastric emptying. The radionuclide 99mTc as
technetium Tc 99m sulfur colloid mixed with
cooked liver made into a pâté or mixed with egg
white (test meal of 300 g) or 111In as indium In 111
chloride mixed with orange juice is administered
orally to the client. Scanning is performed after the
meal, and an analysis of the delayed emptying curve
(the percent of food retained compared with the
time) provides the diagnostic information.43
The study can include the administration of
metoclopramide (Reglan) to evaluate the effect of
the drug on gastric motility, providing that no
obstruction is present.44
Reference Values
Normal gastric emptying of standard test meal;
no abnormal gastric function or mechanical
obstruction

CHAPTER 20—Nuclear

INTERFERING FACTORS

Inability of client to remain still during the procedure
Food intake during the fasting period before the
study, which would affect emptying time
Medications such as anticholinergics or narcotics
that affect motility
INDICATIONS FOR GASTRIC EMPTYING
SCANNING

Determining the existence of mechanical obstruction caused by gastric tumor or ulcer disease
revealed by delayed emptying time
Evaluating gastric function or absence of function
revealed by delayed emptying in diabetic
neuropathy or gastroparesis
Determining the cause, after surgery, of delayed
gastric emptying caused by a nonfunctioning
anastomosis
Determining the cause of delayed gastric emptying in conditions such as anorexia, diabetes, scleroderma, or amyloidosis
Evaluating the effects of medication regimens
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Instruct the client to withhold food and medications that can decrease motility for 8 hours before
the study; also specify whether fluid intake is
allowed.
Inform the client of the scanning schedule and
explain that the study takes 1 hour or longer,
depending on the time it takes the stomach to
empty.
History should include information about
gastrointestinal status and known or suspected
abnormal conditions, as well as results of associated diagnostic tests and procedures.
THE PROCEDURE

The client is requested to ingest the test meal
containing the radiopharmaceutical as quickly as
possible. Use of a standardized test meal allows accurate determination of gastric emptying because the
rate of emptying varies with meal size and caloric
content. The client is maintained in a sitting position; after the ingestion of the test meal, the images
are obtained at 10- and 20-minute intervals in anterior and posterior views. Imaging is then performed

Scan and Laboratory Studies

503

over the stomach with the client in a supine position
until the stomach empties (normally 1 to 11/2
hours). Emptying time is calculated based on data
obtained from the computer system as well as on the
percentage of counts obtained, decay time of the
radionuclide, and depth variables. An emptying
curve is determined by calculating the percentage of
retention versus the time. These results are interpreted by the nuclear medicine physician at the
completion of the procedure. In general, a longer
time indicates impaired gastric emptying and a
shorter time indicates gastric hypermotility.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

GASTROINTESTINAL REFLUX
SCANNING
Gastrointestinal reflux scanning is a nuclear study
performed to assist in diagnosing esophageal reflux
in clients complaining of heartburn and regurgitation. This disorder is common in the adult population, but it also occurs in infants and children,
causing significant complications such as esophagitis, stricture, aspiration pneumonia, and failure to
thrive.45 Lung scanning can be performed if aspiration of gastric contents into the lungs is suspected.
The study can be combined with the gastric emptying study because reflux is known to be associated
with a delay in emptying. The radionuclide 99mTc as
technetium Tc 99m sulfur colloid is mixed with
orange juice or other acidic fluid and administered
orally. Scanning is performed over the gastroesophageal area and later over the lungs, if aspiration
is suspected. This study is more sensitive for this
condition than is endoscopy, fluoroscopy, or
manometry to measure esophageal sphincter pressure.
Esophageal motility studies are performed to
diagnose achalasia and esophageal spasms. The technetium Tc 99m sulfur colloid is mixed with water
and administered to the client, followed by scanning.
A significant reduction in esophageal activity indicates the presence of abnormalities. This test is more
sensitive than esophageal manometry in clients with
complaints of dysphagia.46
Reference Values
Normal passage of fluid through the esophagus
into the stomach; no reflux into the esophagus
from the stomach

504

SECTION II—Diagnostic

Tests and Procedures

INTERFERING FACTORS

Inability of client to remain still during the procedure
Any condition that prevents application of the
compression binder during the procedure
INDICATIONS FOR GASTROESOPHAGEAL
REFLUX SCANNING

Unexplained persistent heartburn, dysphagia, or
regurgitation that occurs frequently and regularly
Evaluating esophageal function and detecting the
presence of reflux with more accuracy than is
possible with endoscopic or radiologic studies
Diagnosing esophageal motility disorders, such as
spasms; achalasia is revealed by a prolonged transit time
Differentiating between significant and insignificant reflux in infants
Detecting aspiration of gastric contents into the
lungs (aspiration scan)
Diagnosing reflux when performed with the
gastric emptying study, because the condition is
linked to delayed gastric emptying
Evaluating the effectiveness of surgical or medical
interventions for gastroesophageal reflux
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Instruct the client to restrict food or ingest a meal
before the study, depending on the policy of the
nuclear medicine department.
Inform the client of the scanning schedule and
explain that the study takes 30 minutes.
History should include information about
gastrointestinal status and complaints resulting
from an abnormality.

the computer at each pressure level, and the reflux is
calculated for each pressure level. Esophageal motility or transient time can be determined by the presence of radionuclide in the esophagus. If an infant is
scanned, the radiopharmaceutical is administered in
the formula or instilled via a gastrointestinal tube,
and imaging is performed at intervals for 1 hour.
If an aspiration scan is performed, the radiopharmaceutical is given to the client in the evening meal
before the study. The client remains in the supine
position until morning, and scanning is performed
over the lungs to note uptake of the radionuclide,
indicating aspiration.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

GASTROINTESTINAL BLEEDING
SCANNING
Gastrointestinal bleeding scanning is a nuclear study
performed to assist in locating bleeding sites in the
upper tract proximal to the ligament of Treitz or in
the lower tract distal to the ligament of Treitz. This
study is much more sensitive than is endoscopy,
barium-mediated radiography, or angiography in
locating a bleeding site in the lower gastrointestinal
(LGI) tract, although very slight rectal hemorrhages
can be missed. Only the site of the bleeding is
revealed, not the cause of it. The radionuclide 99mTc
as technetium Tc 99m sulfur colloid or technetium
Tc 99m RBC is injected IV, and scanning of the
abdominal quadrants is performed. Abnormal flow
and static studies reveal a focal area of increased
intensity of activity during initial scanning with
technetium Tc 99m sulfur colloid. The same abnormalities are revealed to locate slow or intermittent
bleeding during delayed scanning of up to 24 hours
with technetium Tc 99m RBC. Surgical intervention
is usually required to correct a persistent bleeding
problem.

THE PROCEDURE

The client is given the radiopharmaceutical in 300
mL of orange juice and is then placed in an upright
position for scanning. The client is requested to
remain still, and imaging is performed in 10 to 15
minutes over the esophageal area. Imaging is also
performed in other positions to determine whether
reflux occurs in a specific position. After this initial
imaging, an abdominal compression binder is
applied to sequentially lower esophageal sphincter
pressure 5 mm Hg at a time. Images are recorded on

Reference Values
No active bleeding at any gastrointestinal tract
site
INTERFERING FACTORS

Inability of client to remain still during the procedure
Barium in the tract from previous radiologic
studies

CHAPTER 20—Nuclear

INDICATIONS FOR GASTROINTESTINAL
BLEEDING SCANNING

Detecting and localizing recent or active bleeding
sites before medical or surgical treatments
Identifying and localizing small sites of bleeding
in the lower tract caused by tumor, diverticula,
angiodysplasia, or inflammatory bowel disease;
sites are revealed by focal area of increased activity
Detecting and localizing upper tract hemorrhage
caused by medications such as heparin, warfarin,
aspirin, or corticosteroids or conditions such as
gastritis, ulcer, or varices (gastric or duodenal)
Detecting bleeding from stress ulcer in severely
stressed clients
Diagnosing and detecting bleeding sites in children with intussusception, Meckel’s diverticulum,
or juvenile polyps
Determining bleeding in the tract from unknown
source revealed by increased focal area of activity
in flow and static images
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
Hemodynamic instability that presents a risk
because of the prolonged time needed for the
study
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client of the scanning schedule for
immediate and delayed imaging, and explain that
each test takes 30 minutes.
Take baseline vital signs and monitor if their
stability is questionable.
History should include information about conditions and medication regimen that can lead to
hemorrhage.

Scan and Laboratory Studies

505

longer imaging time is required to detect slow bleeding rate, and the technetium Tc 99m RBC allows
intermittent imaging for 24 hours without reinjection.47
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Continue monitoring vital signs if bleeding is
present.
Hemorrhage/shock state: Note and report upper
gastrointestinal (UGI) or LGI blood loss and
amount (vomiting, feces), decreasing blood pressure, increased pulse, and pallor and coolness of
skin. Monitor vital signs. Prepare for ordered
blood transfusion, surgery, or both, to control
bleeding.

MECKEL’S DIVERTICULUM SCANNING
Meckel’s diverticulum scanning is a nuclear study
performed to assist in diagnosing the presence and
size of this congenital anomaly of the gastrointestinal tract. The condition can become symptomatic in
children and adults, causing bleeding, diverticulitis,
volvulus, or intussusception. The radionuclide 99mTc
as technetium Tc 99m pertechnetate is administered
IV, and immediate and delayed imaging are
performed of the abdominal lower right quadrant
(LRQ). The radionuclide is taken up and concentrated by gastric mucosa, a type of tissue found in
Meckel’s diverticulum, and a focal increase in activity is associated with an abnormality.

Reference Values
Normal distribution of radionuclide by gastric
mucosa at normal sites; no ectopic gastric
mucosa revealed by uptake activity in abnormal
structures

THE PROCEDURE

The client is placed on the examining table in a
supine position. The client is requested to remain
still during the study, and the radiopharmaceutical is
administered IV. Imaging for flow studies is
performed immediately every 5 seconds for 60
seconds. Static imaging is performed every 1 to 2
minutes for 30 minutes, then at 45 minutes, and at 1
hour. Lateral and oblique views of the upper
abdomen are taken to obtain an image of a higher
bleeding site if the lower portion is negative (reveals
no focal increase activity of the radionuclide). A

INTERFERING FACTORS

Inability of client to remain still during the procedure
Barium in the bowel from previous radiologic
studies
INDICATIONS FOR MECKEL’S DIVERTICULUM
SCANNING

Unexplained abdominal pain and gastrointestinal
bleeding in adults and children as a result of
hydrochloric acid and pepsin secretions by

506

SECTION II—Diagnostic

Tests and Procedures

ectopic gastric mucosa causing ulceration of
nearby mucosa48
Detecting sites of ectopic gastric mucosa revealed
by focal increased activity in areas other than
normal structures
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client of the scanning schedule and
explain that the study takes 1 hour.
Instruct the client to restrict food for 6 to 8 hours
and to restrict water and medications according to
agency policy or physician preference.
Advise that a nasogastric (NG) tube may be
inserted and medications administered during the
procedure to enhance imaging.
A histamine H2 antagonist, cimetidine (Tagamet),
in doses of 300 mg four times per day, is administered 2 days before the scan to block acid secretion
and to keep the radionuclide from gastric mucosa.
This practice improves the lesion-background
ratio in the scan.49
History should include information about signs,
symptoms, and conditions associated with
Meckel’s diverticulum, such as pain, bleeding,
intussusception, volvulus, and diverticulitis, and
results of diagnostic tests and procedures.
THE PROCEDURE

The client is placed on the examining table in a
supine position and the radiopharmaceutical is
administered IV. Initial anterior abdominal images
are obtained for 1 minute to screen for a vascular
lesion that could cause bleeding. The client is
requested to remain still during the scanning and is
informed that positions are changed to obtain
different views. Delayed imaging of the left upper
portion of the abdomen to obtain stomach views
and of a lower field of view of the bladder is
performed. Imaging takes place every 5 minutes for
1 hour in anterior, oblique, and lateral views, including a postvoiding view. Modifications can be made
to facilitate the study, such as positioning the client
on the left side with the table tilted 45 to 90 degrees
to decrease emptying of the radiopharmaceutical
from the stomach into the bowel. Another modification is insertion of an NG tube into the stomach to
decrease peristalsis and emptying of the radiopharmaceutical from the stomach into the bowel. Also,

glucagon or pentagastrin, or both, can be administered to control uptake of the radionuclide.50
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

PANCREAS SCANNING
Pancreas scanning is a nuclear study performed to
assist in the diagnosis of pancreatic disease resulting
from abnormalities of the exocrine portion of the
organ. Focal lesions are identified by the absence
of uptake of the radionuclide selenium 75 (75Se)
during scanning, which indicates the presence of a
tumor or inflammatory process when the procedure
is performed in combination with ultrasonography
and evaluation of laboratory enzyme levels. Other
processes that impede the secretory ability leading to
the stimulation of pancreatic enzyme formation and
secretion into the bowel are vagotomy, acute peptic
ulcer, ascites, cancer, starvation, and gastroenterostomy. Enzyme production decreases the radionuclide uptake and determines the diagnosis of
pancreas pathology.51
Reference Values
Normal function and anatomically intact pancreas; no decreased radionuclide uptake indicating pancreatic disease
INTERFERING FACTORS

Inability of client to remain still during the procedure
INDICATIONS FOR PANCREAS SCANNING

Determining pancreatic functional process affecting enzyme formation and secretion revealed by a
diffuse decrease in radionuclide uptake
Detecting tumors or chronic inflammation,
although diagnostic value is limited, revealed by
focal lesion that decreases the uptake of the
radionuclide
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

CHAPTER 20—Nuclear

History should include a gastrointestinal assessment and medications affecting pancreatic function, as well as results of diagnostic tests and
procedures.
THE PROCEDURE

The client is placed on the examining table in a
supine position. He or she is then requested to
remain still during the scanning, and selenomethionine Se 75 is administered IV. Scanning over the
abdominal area is performed and images are
obtained and compared with other studies to determine abnormalities that the scan alone cannot
detect.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

LIVER SCANNING
Liver scanning is a nuclear study performed to assist
in diagnosing abnormalities in the structure and
function of that organ. It can be performed simultaneously with spleen scanning or in combination
with lung scanning to assist in the diagnosis of
masses or inflammation in the diaphragmatic area.
The radionuclide 99mTc as technetium Tc 99m
sulfur colloid is injected IV and taken up by the
Kupffer cells that normally function to remove
particulate matter, including radioactive colloids, in
the liver. Early or delayed and increased or decreased
uptake indicate pathology when flow studies are
performed (dynamic scintigraphy). Static imaging
reveals abnormalities in size and shape of the liver in
the presence of pathology.52
Liver scans are evaluated with liver function laboratory studies and can complement ultrasonography
and CT in confirming a diagnosis. Scanning is also
performed to confirm catheter placement for
chemotherapy and to determine whether a tumor is
being infused and the normal parenchyma bypassed.
This procedure is accomplished by imaging after the
slow IV infusion of 99mTc administered as technetium Tc 99m MAA and later imaging after an
injection of technetium Tc 99m sulfur colloid and
computer subtraction.53
Reference Values
Normal size, shape, position, and function of the
liver; no tumors, cysts, inflammation, trauma, or
infiltrative disease

Scan and Laboratory Studies

507

INTERFERING FACTORS

Inability of client to remain still during the procedure
Barium in the gastrointestinal tract from previous
radiography
Other nuclear scans performed on the same day
INDICATIONS FOR LIVER SCANNING

Diagnosing primary or metastatic tumor and
differentiating between them as revealed by
uptake that appears as a filling defect or by solitary or multiple focal “cold” defects
Diagnosing diffuse hepatocellular disease, such as
hepatitis, cirrhosis (early and advanced), or
hepatomegaly; shunting to spleen or bone
marrow revealed by patchy, decreased uptake in
hepatitis or atrophy; and shunting to spleen or
bone marrow and decreased or absent uptake in
cirrhosis
Diagnosing benign tumors such as adenoma or
cavernous hemangiomas as revealed by
hepatomegaly or solitary “cold” defect
Detecting bacterial abscess revealed by solitary or
multiple “cold” defects, especially after gastrointestinal surgery
Detecting amebic abscess revealed by solitary
defect, especially after amebiasis
Diagnosing cystic focal disease revealed by “cold”
defects
Determining the effect of traumatic lesions such
as lacerations or hematomas
Detecting infiltrative processes of the liver such as
sarcoidosis or amyloidosis
Evaluating palpable abdominal masses and
differentiating between splenomegaly and
hepatomegaly
Determining superior vena cava obstruction or
Budd-Chiari syndrome revealed by increased
uptake of the radionuclide, or “hot spots”
Evaluating liver damage caused by radiation therapy or hepatotoxic drug therapy
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

508

SECTION II—Diagnostic

Tests and Procedures

well as past medical and surgical treatment or
regimens.
THE PROCEDURE

Barium in the gastrointestinal tract from prior
radiography
INDICATIONS FOR SPLEEN SCANNING

The client is placed on the examining table in a
supine position. The client is then requested to
remain still during the scanning and the radiopharmaceutical is administered IV. Scanning follows in 1
to 2 seconds and continues for 30 minutes to 1 hour
to perform flow studies. A 1-minute blood pool
image can also be performed. This image is followed
by static imaging in the anterior, posterior, laterals,
anterior-oblique, and posterior-oblique views to
determine the size and shape of the liver. Defects
that fail to take up the radionuclide (normally
concentrated in the Kupffer cells in the liver) are
known as “cold spots.” Normal indentations in the
liver can be confused for focal diseases of the liver.
SPECT imaging, a three-dimensional study, can be
performed to obtain more specific views of the liver.
The liver scan is performed in combination with a
lung scan when a systemic tumor or infection is
suspected in the upper abdomen or below the
diaphragm.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

SPLEEN SCANNING
Spleen scanning is a nuclear study performed to
assist in diagnosing abnormal structure or function
of this organ. It is often performed to differentiate
between splenomegaly and hepatomegaly, and it is
performed in combination with liver scanning
because the radionuclide is distributed in both
organs at the same time (86 percent in the liver and
6 percent in the spleen). The radionuclide 99mTc
administered as technetium Tc 99m sulfur colloid is
injected IV, followed by scanning. The appearance or
absence of “cold” defects or the appearance of multiple “cold” defects, resulting from the presence of the
radionuclide on the images, determines splenic
pathology.
Reference Values
Normal size, length, perfusion, and function of
the spleen; no infarction, hematoma, tumor,
abscess, or cysts
INTERFERING FACTORS

Inability of client to remain still during the procedure

Determining splenic arterial obstruction or
pathological infiltration resulting from splenic
inflammation or infarction as revealed by a
marked decrease in radionuclide compared with
liver intake
Determining splenic involvement in diseases such
as leukemia, lymphoma, or melanoma as revealed
by splenic enlargement and focal changes
Determining splenic rupture or hematoma after
abdominal trauma as revealed by splenomegaly
and diffuse diminished radionuclide uptake
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those for the liver scan (see section under
“Brain Scanning” and preceding “Liver Scanning”
section).
THE PROCEDURE

The procedure is the same as for liver scanning (see
preceding section). To obtain flow studies, imaging
for 1 minute begins 30 minutes after injection of the
radiopharmaceutical. Static imaging is performed to
determine the size (anterior view), length (posterior
view), and shape (lateral and anterior views) of the
organ.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

DEEP VEIN SCANNING
Deep vein scanning, or fibrinogen uptake study, is a
nuclear study performed to assist in diagnosing
thrombi in the lower extremity veins. It allows detection of newly formed as well as old clots. The
radionuclide iodine 125 (125I) as fibrinogen I 125
is administered IV followed by immediate and
delayed scanning. Increased uptake of the radionuclide indicates an abnormality because fibrinogen is
involved in blood clotting and appears at the clot
site. This study can be continued on a daily basis for
up to 1 week after the injection in clients at risk for
formation of deep venous thrombosis (DVT), that
is, in postoperative, postpartum, and immobile
clients.54

CHAPTER 20—Nuclear

Reference Values
Normal structure of veins of lower extremities
and venous patency; no formation or presence
of DVT
INTERFERING FACTORS

Inability of client to remain still during the procedure
Other abnormalities in the extremity, such as
infection, edema, or phlebitis, that cause fibrinogen concentration
INDICATIONS FOR DEEP VEIN SCANNING

Detecting DVT in its earliest stages, especially in
immobilized clients, as revealed by steadily
increased counts over 1 to 2 weeks
Diagnosing and identifying the area of clot
formation revealed by increased counts when
compared with the opposite extremity
Diagnosing DVT in clients who are too ill for
radiographic venography or who are sensitive to
the contrast media used
CONTRAINDICATIONS

Allergy to iodine, unless a steroid or antihistamine
is administered before the study
Need for diagnosis of DVT immediately or sooner
than 24 hours
Lymphedema, cellulitis, superficial phlebitis, or
active arthritis55
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client that a radiation Geiger-type
detector is the device used for scanning and that
the study takes 1 hour.
Administer potassium iodide before and during
the procedure to prevent uptake of the radionuclide by the thyroid gland, which would affect
uptake in the areas to be examined.
History should include chronic disorders of the
vascular system of the extremities; allergies to
iodine; and signs, symptoms, and risks for DVT.
THE PROCEDURE

The areas on the extremity to be scanned are
marked, and the radiopharmaceutical is administered IV. The client is requested to remain still, and
the marked areas (calf and thigh) are scanned 10
minutes after the injection. A Geiger-type device is
used to detect and count radiation levels. This
provides a baseline for later comparisons when scan-

Scan and Laboratory Studies

509

ning is performed in 24 hours. In some cases, scanning is performed daily for 7 or more days after the
injection of the radiopharmaceutical because it takes
that long for the radionuclide to concentrate in
possible thrombi. Subsequent scanning of the
marked areas in 24 hours is compared with the
amount of uptake in the opposite extremity. A reading of 15 times greater than the baseline or the
opposite extremity reading indicates DVT.56
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

GALLBLADDER/BILIARY SYSTEM
SCANNING
Gallbladder and biliary system scanning is a nuclear
study performed to assist in diagnosing gallbladder
disease and duct obstruction. The radionuclide
99m
Tc as Tc 99m diisopropyl iminodiacetic acid
(DISIDA) is administered IV followed by serial
imaging. Biliary and duct concentrations are
achieved by the liver excretion of the radionuclide
into the bile. Failure of the substance to enter the
gallbladder demonstrates duct obstruction, and the
organ and ducts will not be visualized. The ejection
capabilities of the gallbladder can also be calculated
to evaluate gallbladder functional disorders.57
Compared with ultrasonography, this study
demonstrates a higher sensitivity in providing diagnostic information. It is also preferred for clients with
sensitivities to contrast media used in oral cholecystography or IV cholangiography, and it provides
information about clients with bilirubinemia, information not obtainable with cholangiography.
Reference Values
Normal size, shape, and function of the gallbladder with patent cystic and common bile
ducts; no inflammation of the gallbladder or
obstruction of ducts
INTERFERING FACTORS

Inability of client to remain still during the procedure
Absence of food ingestion for longer than 24
hours as in fasting, total parenteral nutrition, or
alcoholism
Bilirubin levels of greater than 30 mg/dL depending on the radionuclide used, because increased
bilirubin decreases hepatic uptake

510

SECTION II—Diagnostic

Tests and Procedures

INDICATIONS FOR GALLBLADDER/BILIARY
SYSTEM SCANNING

Suspected gallbladder disorders such as inflammation, perforation, or calculi as revealed by
decreased or absent radionuclide flow to the gallbladder or into the peritoneal cavity
Diagnosing acute cholecystitis revealed by nonvisualization in 1 hour after the injection of the
radiopharmaceutical
Diagnosing chronic cholecystitis revealed by a
delayed visualization caused by fibrosis, calculi, or
viscous bile
Determining common duct obstruction caused
by tumor or cholelithiasis revealed by a dilated
duct; nonvisualization of the common bile duct,
gallbladder, and duodenum; or visualization of
the common bile duct or gallbladder with absence
of flow into the duodenum
Evaluating biliary enteric bypass patency after
surgery as revealed by delayed bowel visualization
Assessing obstructive jaundice when the procedure is performed in conjunction with radiography or ultrasonography
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Instruct the client to restrict food and fluid for 4
to 6 hours before the study.
Explain the scanning schedule and that the study
takes 1 to 4 hours.
Inform the client that a fatty meal or medication
may be given during the study for special additional tests.
History should include hepatic and gallbladder
conditions and laboratory function tests and signs
and symptoms of biliary system abnormalities.
THE PROCEDURE

The client is placed on the examining table in a
supine position. The client is then requested to
remain very still during the imaging, and the radiopharmaceutical is administered IV. Scanning begins
immediately, with images taken every 5 minutes for
the first 30 minutes and every 10 minutes for the
next 30 minutes. Delayed views are taken in 2, 4, and
24 hours if the gallbladder is not visualized to differentiate acute from chronic cholecystitis or to detect
the degree of obstruction. Instruct the client to

restrict fats during the 24 hours before returning to
the department for further scanning. The drug
sincalide is given by some departments before the
study to promote release of cholecystokinin, which
causes the gallbladder to contract and empty. Also, if
the organ is not visualized within 1 hour after injection of the radiopharmaceutical, morphine sulfate
can be administered to initiate spasms of the sphincter of Oddi, forcing the radionuclide into the gallbladder. Imaging is then performed 20 to 50 minutes
after the morphine administration to determine
delayed visualization or nonvisualization related to
cystic duct patency.58
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Resume food and fluids after the study, and monitor for mentation effects of morphine sulfate, if it
was administered.

KIDNEY/RENOGRAPHY SCANNING
Kidney scanning is a nuclear study performed to
assist in diagnosing abnormal blood flow, collecting
system defects, and excretory function of the organs.
It can also provide information about the size and
shape of the kidneys. Flow studies, excretion studies,
determination of glomerular filtration rate (GFR),
and static imaging reveal the presence of the different types of pathology. Such pathology includes
vascular disease, inflammation or infection, obstructive uropathy, masses, congenital anomalies, acute or
chronic renal failure, and the effects of trauma or
injury. Renography involves the times of uptake and
excretion of the radionuclide by the kidneys, which
is plotted on a graph and compared with normal
parameters of organ function.59
Several radiopharmaceuticals administered IV are
used in kidney scanning, depending on their distribution in the organs. Technetium 99m administered
as technetium Tc 99m DTPA is used to study blood
flow and GFR, and technetium Tc 99m dimercaptosuccinic acid (DMSA) or technetium Tc 99m
gluceptate is used to assess the parenchyma for
structural defects with static imaging; technetium Tc
99m glucoheptonate is the agent of choice for children. Iodine 131 as orthoiodohippurate (OIH) I 131
is administered to study renal plasma flow and tubular secretion. The time schedule for scanning varies
with the radiopharmaceutical administered and the
information to be obtained. Abnormalities are
identified by a delayed, diminished, or absent flow
to the affected kidney. A triple renal study can be

CHAPTER 20—Nuclear

performed with the administration of two IV injections of radiopharmaceuticals to obtain perfusion,
excretion, and structural information.
Another study performed on the genitourinary
system involves imaging of the valve action at the
ureterovesicular junction to assist in the diagnosis of
vesicoureteral reflux. It is performed on adults and
children using technetium Tc 99m DTPA instilled
into the bladder. This procedure is preferred over
voiding cystourethrography because it has a very low
radiation exposure to the bladder and surrounding
organs.60
Reference Values
Normal size, shape, position, symmetry, perfusion, and function of the kidneys; no renal
vascular disease, trauma, infection or inflammation, obstructive uropathy, masses, congenital
anomalies, or renal failure
INTERFERING FACTORS

Inability of client to remain still during the procedure, especially if the client is a child
Antihypertensives taken within 24 hours of the
study
INDICATIONS FOR KIDNEY/RENOGRAPHY
SCANNING

Diagnosing renal artery stenosis resulting from
dysplasia or atherosclerosis and causing arterial
hypertension and reduced glomerular filtration
revealed by a diminished flow to the affected
kidney
Diagnosing renal vein thrombosis resulting from
dehydration in infants or obstruction of blood
flow resulting from tumors in adults revealed by
enlarged kidney and decreased flow
Diagnosing renal artery embolism or renal infarction causing obstruction as revealed by absent
flow and function
Determining effect of renal trauma such as arterial injury, renal contusion, hematoma, rupture,
AV fistula, or urinary extravasation as revealed by
decreased or absent flow and an abnormal renal
outline
Detecting renal infection or inflammatory disease
such as acute or chronic pyelonephritis, renal
abscess, or nephritis as revealed by decreased
perfusion in the affected area, decreased kidney
size, and scarring
Determining and locating the cause of obstructive
uropathy such as calculi, neoplasm, inflammation, or congenital disorders as revealed by

Scan and Laboratory Studies

511

delayed or reduced blood flow to the affected
kidney; determining and locating the cause of
nonvisualization of the bladder in complete
obstruction and nonvisualization of the kidney if
the obstruction is of long standing
Detecting cystic disease such as simple cysts, polycystic disease in children or adults, or medullary
sponge kidney or cystic disease in adults as
revealed by abnormal renal size and shape, single
or multiple cysts, or unperfused or perfused areas,
depending on the type of cyst
Detecting type, position, and number of congenital anomalies such as ectopic kidney, horseshoe
kidney, supernumerary kidneys, or agenesis of left
kidney as revealed by changes in size, shape, or
position of kidney(s)
Evaluating acute and chronic renal failure as
revealed by a reduction in uptake, depending on
renal function, and by an absence of uptake in
renal insufficiency, indicating a poor prognosis
Evaluating kidney transplant for acute or chronic
rejection as revealed by decreased flow and function early in rejection, acute tubular necrosis
within 24 hours of rejection with absence of
excretion from the kidney, acute rejection within
5 days postoperatively, and chronic rejection
revealed by ongoing decreased flow and function
Determining vesicoureteral reflux in children as
revealed by reflux during bladder filling or
micturition, or both, during or after voiding, and
calculating the amount of reflux61
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client of the scanning schedule, and
explain that the study takes 30 to 60 minutes
initially but that an additional 4 hours are needed
if special imaging or a renogram is to be
performed.
Ensure that the client has had adequate fluid
intake before the study and provide 2 glasses of
fluids to drink immediately before the study.
Advise the client to withhold antihypertensive
medications 24 to 48 hours before the test.
Administer ordered Lugol’s solution before the
study to reduce uptake of the radionuclide by the
thyroid gland.
Inform the client that additional medications may
be administered during the study.

512

SECTION II—Diagnostic

Tests and Procedures

History should include information about renalurinary status and results of renal function laboratory tests (blood urea nitrogen, creatinine).
THE PROCEDURE

The client is placed on the examining table in a
prone, supine, or sitting position depending on the
study to be performed. Positions can be changed
during the imaging. The client is requested to
remain still during the scanning procedure. The
radiopharmaceutical for flow studies is administered
IV and sequential imaging is performed every 2
seconds for 30 to 60 seconds. Blood pool imaging
can also be obtained at this time. Excretion studies
are performed after the administration of the appropriate radiopharmaceutical, and one image every
minute for 3 minutes at 30-minute intervals is
obtained. There is an immediate uptake for flow and
excretory studies, with a peak at 3 to 5 minutes,
followed by a decline. Renal pelvis and bladder activities can be seen in 3 to 6 minutes. Excretion studies
are best performed on the hydrated client, unless the
study is performed for hypertension. These are
followed by static imaging to reveal the collecting
system and delayed static imaging 2 to 3 hours later
to reveal cortex abnormalities. In some cases, imaging can be performed 24 hours later, especially in
clients with renal failure, because this condition
slows the uptake of the radionuclide. All information obtained is stored in a computer for further
interpretation and computation. During the flow
and static imaging, a loop diuretic such as
furosemide (Lasix) can be administered IV to
encourage large urinary output, which is then
followed by imaging.62
Renogram curves can be plotted concurrently
with flow studies in which blood flow is imaged and
recorded as it occurs. Information is displayed and
a chart recording is made. A curve is plotted based
on the amount of radionuclide uptake over a period
of time, which results in curve shapes with diagnostic value. The graphed data provide information
about vascular, tubular, and excretory phases of
radionuclide uptake and removal by the kidneys.
Urine and blood laboratory studies are performed
after the renogram to correlate findings before diagnosis.63
For a vesicoureteral reflux procedure, the client is
requested to void and a catheter is inserted into the
bladder. The radiopharmaceutical is instilled into
the bladder, and multiple images are obtained
during bladder filling. The client is then requested to
void after catheter removal or the bladder is emptied
with the catheter in place, depending on department
policy. Imaging continues during voiding and after

voiding is completed. Reflux is determined by calculating the urine volume and counts obtained by
imaging. This study is preferred for children who
require repeated studies for long-term care for vesicoureteral reflux to avoid the high gonadal radiation
exposure that results from x-ray contrast
cystourethrography.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

SCROTAL SCANNING
Scrotal scanning is a nuclear procedure performed
to assist in diagnosing diseases and disorders of
the testis, epididymis, spermatic cord, and other
contents of the scrotal sac. An IV injection of 99mTc
as technetium Tc 99m pertechnetate is administered, and perfusion and tissue studies are
conducted. Based on an increased radionuclide
activity and flow, arterial and venous supply, torsion,
infections, and tumor abnormalities can be imaged.
Reference Values
Normal blood flow and structures of scrotal
contents; no tumor, hematoma, infection or
inflammation, or torsion
INTERFERING FACTORS

Inability of client to remain still during the procedure, especially if the client is a child
INDICATIONS FOR SCROTAL SCANNING

Unexplained testicular pain and swelling to determine the cause
Determining infectious processes and differentiating between epididymitis and orchitis as
revealed by increased flow and focal increase of
the radionuclide
Diagnosing hydrocele or varicocele as revealed by
radionuclide concentration, depending on the
size
Diagnosing torsion abnormalities as revealed by
absence of perfusion on the affected side and
decreased activity of the radionuclide in the tissue
of the affected side when compared with the unaffected side
Evaluating the effects of trauma such as
hematoma or hematocele as revealed by diffuse
increase of flow

CHAPTER 20—Nuclear

Determining the existence and placement of
inguinal hernia as revealed by intake extending
from the inguinal region to the scrotum
Diagnosing benign and malignant tumors of the
testes as revealed by diffuse increased uptake with
some decreased areas
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client that the study takes 30 to 60
minutes. A child should be accompanied by the
parent of the child’s choice.
History should include information about the
reproductive system and signs and symptoms
associated with disorders of the scrotum and its
contents.
THE PROCEDURE

The client is placed on the examining table in a
supine position. Potassium perchlorate is administered orally to block thyroid uptake of the radionuclide. The penis is taped in a position over the pubis.
If needed, a sling or towel is used to support the
scrotum and the scrotum is positioned in the field of
the scanner. The client is requested to remain still
during the scanning. Imaging is performed initially
without a lead shield; then a lead shield is positioned
and imaging is repeated. The radiopharmaceutical is
administered IV and flow study imaging is
performed for 60 seconds at 3- to 6-second intervals.
Delayed imaging is then performed to scan the scrotum and activity of the sac contents.64
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

GALLIUM 67 SCANNING
67

Gallium 67 ( Ga) body scanning is a nuclear study
performed to assist in diagnosing neoplasm and
inflammatory activity in any body tissue or organ.
To identify the presence and location of these abnormalities, the radionuclide 67Ga as gallium citrate Ga
67 is administered IV, followed by a total body scanning procedure. This radionuclide is readily distributed throughout the plasma and body tissues with a
90 percent sensitivity for inflammatory disease. It
binds to transferrin receptors on cell surfaces, which
is useful in identifying the presence of tumors, and
to lactoferrin in neutrophils, which is useful in identifying inflammatory lesions.

Scan and Laboratory Studies

513

Reference Values
Normal organ systems in the body; no tumors
or infectious processes in the body tissues.

INTERFERING FACTORS

Inability of client to remain still during the procedure
Antineoplastic drug therapy affecting the results
of the study
INDICATIONS FOR GALLIUM 67 SCANNING

Detecting infections or inflammatory diseases
such as amebic and perinephric abscess,
pyelonephritis, osteomyelitis, septic arthritis, and
Pneumocystis carinii pneumonia as revealed by
increased uptake of the radionuclide in the
affected organ
Detecting primary and metastatic tumor in the
lung, bone, brain, liver, head and neck, or
gastrointestinal and genitourinary tracts as
revealed by uptake of the radionuclide, depending
on the organ system involved
Diagnosing and determining the stage of
lymphomas, especially in Hodgkin’s disease, and
bronchogenic cancer as revealed by uptake in
lymph nodes or extranodal locations
Detecting primary hepatoma, sarcoma, melanoma, or sarcoidosis as revealed by an abnormal
uptake of the radionuclide in related organs
Differentiating between benign and malignant
tumors and detecting recurrent tumors when
performed in combination with other studies
such as CT and ultrasonography
Screening for abnormalities when performed with
other nuclear scan studies using 99mTc or 111In
Determining effectiveness of chemotherapy or
radiation therapy
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client that the scanning schedule can
extend over 3 days and that each scanning procedure takes 1 to 2 hours.
Administer an ordered suppository or tap water
enema, or both, before the study.
History should include information about the

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SECTION II—Diagnostic

Tests and Procedures

physical examination of all systems and results of
any previous diagnostic tests and procedures.
THE PROCEDURE

The client is placed on the examining table in a
supine position. The radiopharmaceutical is administered IV, with the amount dependent on whether
tumor or inflammation imaging is to be performed.
The client is requested to remain still during the
scanning. Because of slow blood clearance, scanning
is performed in 6, 24, 48, or 72 hours, or at more
than one or at all of these times, for infectious or
inflammatory identification. Scanning is performed
in 24 and 48 hours, with delayed imaging up to 120
hours possible, for tumor identification. Soft tissue
activity is present on 6- and 24-hour scans, and this
activity decreases for scans performed after the
initial 24 hours because of slow blood clearance.
Depending on the reason for the scan, anterior and
posterior views of the head, neck, chest, and
abdomen and anterior views of the extremities are
performed in whole body scanning. Lateral and
oblique views can also be performed.

anywhere outside of the normal thyroid gland
after thyroidectomy
Determination of metastasis from a diagnosed
primary thyroid malignancy
After administration of 131I therapy for thyroid
cancer
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client of the scanning schedule and
explain that imaging takes 2 to 3 hours.
Ensure that changes in client’s thyroid medication
regimen and administration of other medications
have been implemented before the study.
History should include thyroidectomy, postoperative treatments, medication regimen, and results
of other diagnostic tests and procedures.

NURSING CARE AFTER THE PROCEDURE

THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

The client is given an oral dose of the radiopharmaceutical in a capsule and returned to or requested to
return to the department 24 to 72 hours later. The
client is then placed on the examining table in a
supine position and requested to remain still while
full body scanning is performed. Thyroid-stimulating hormone (TSH) can be administered IV before
the radiopharmaceutical to stimulate any residual
tissue to take up the radionuclide, if this is the reason
for the study. A higher level of TSH also increases
uptake by metastatic tumors.

IODINE 131 SCANNING
Iodine 131 body scanning is a nuclear study
performed to assist in diagnosing metastatic thyroid
cancer anywhere in the body or in detecting
extrathyroidal tissue or residual thyroid tissue after a
total thyroidectomy. The radionuclide 131I as MIBG
I 131 is administered orally, followed by scanning to
reveal concentrations in the neck, lungs, or bones,
indicating metastatic activity.
Reference Values
Absence of thyroid gland tissue outside of the
thyroid gland; no metastatic tumor from a
primary thyroid malignancy
INTERFERING FACTORS

Inability of client to remain still during the procedure
Other nuclear scans performed before or on the
same day as the body scan
INDICATIONS FOR IODINE 131 SCANNING

Determination of remaining thyroid tissue

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).

POSITRON EMISSION TOMOGRAPHY
PET scanning, as described in the introduction to
this chapter, is a nuclear study performed to assist in
diagnosing central nervous system, cardiac,
pulmonary, and breast disorders. Although these
particular organ systems are the usual ones examined for pathological processes, this procedure can
be performed to examine any part of the body to
obtain clinical information regarding diseases and
effects of therapeutic interventions.
A radionuclide prepared for use in this study,
usually 15O, 13N, 11C, or 18F, capable of emitting a

CHAPTER 20—Nuclear

positron, is administered by IV injection or via
inhalation. PET scanning follows after the radionuclide becomes concentrated in the organ to be studied. The time required for radionuclide
concentration varies with the organ system. As the
positron combines with negative electrons, the
specialized PET scanner translates the emission
from the radioactivity into color-coded images for
viewing and analysis. Scanning is conducted over a
period of time to allow repetition or sequencing of
three-dimensional images. The expense of the study
limits its use, even though it is more sensitive than
are traditional nuclear scanning and SPECT scanning.
Reference Values
Normal blood flow and metabolism in body
tissues; no patterns that reveal organ abnormalities
INTERFERING FACTORS

Inability of client to remain still during the procedure
High anxiety levels that can affect study for brain
function
Use of alcohol, tobacco, or caffeine-containing
beverages at least 24 hours before the study
Tranquilizers that alter mentation or insulin that
alters glucose metabolism
INDICATIONS FOR POSITRON EMISSION
TOMOGRAPHY

Identifying seizure foci in clients with focal
seizures as revealed by decreases in metabolism
between seizures and increases in the ictal state
Diagnosing Alzheimer’s disease and differentiating it from other causes of dementia as revealed
by a decreased cerebral blood flow and metabolism and a change in receptor chemistry
Determining cerebrovascular accident or
aneurysm as revealed by decreased blood flow and
oxygen utilization
Diagnosing Parkinson’s disease or Huntington’s
chorea as revealed by decreased metabolism and
changes in receptor chemistry
Evaluating cranial tumors preoperatively to determine the stage and appropriate treatment or
procedure
Determining physiological changes in psychosis
and schizophrenia as revealed by decreased metabolic activity
Determining the effect of drug therapy as revealed
by biochemical activity of normal and abnormal
tissues

Scan and Laboratory Studies

515

Diagnosing breast tumor, lung infection, and
chronic pulmonary edema, depending on the
radionuclide used and the concentrations at the
sites
Determining the presence of and the extent of
myocardial infarction and the size of the infarct as
revealed by regional metabolic activity in the
heart
Determining CAD as revealed by metabolic state
of the myocardium during ischemia and after
anginal pain
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Inform the client that the study takes 30 to 60
minutes, depending on the organ to be examined.
Instruct the client to restrict smoking and intake
of alcohol or caffeine-containing beverages for 24
hours before the study.
Client should be instructed also to restrict
medications except for a long-acting insulin that
should be administered before a meal 3 to 4 hours
before the study.
Advise the client that a blindfold and earplugs are
used to reduce stimuli during the study if the
brain is being examined.
History should include information about the
system being studied, signs and symptoms that
determined the need for the study, and results of
other diagnostic tests and procedures.
THE PROCEDURE

Brain Study. The client is placed on a reclining bed
in a semiupright position. An IV line is initiated in
each arm. The radionuclide is injected into one line
and serial blood samples are taken from the second
line. The client is requested to perform deep breathing to reduce anxiety. Earplugs and blindfold are
applied to reduce external stimuli. The client is
requested to remain still during the study. Scanning
of the brain begins 45 minutes after the injection,
and the client is requested to read, perform letterrecognition activities, or recite a familiar quotation,
depending on whether speech, reasoning, or
memory is to be tested.
Heart, Lung, or Breast Study. The client is placed
on the examining table in a supine position. The two
IV lines are initiated as for a brain study. Scanning

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SECTION II—Diagnostic

Tests and Procedures

over the chest is performed 45 minutes after the
injection of the radionuclide. The scanning takes
place for 1 hour as the detectors record the radiation
and establish its source in the body. A computer
transforms the rays into a visual display on a screen
for viewing.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Advise the client to assume a standing position
slowly to prevent postural hypotension.

the following formula: counting standard expressed
as counts per minute per milliliter 1000 5, ÷
counts per minute per milliliter in the blood sample.
Plasma volume is calculated using the following
formula: counting standard expressed as counts per
minute 1000, ÷ counts per minute in the blood
sample. When findings in RBC volume exceed 36
mL/kg in male clients and 32 mL/kg in female
clients, polycythemia vera is diagnosed, whereas a
normal or reduced RBC volume indicates stress
polycythemia. Normal or mild changes in plasma
volume indicate polycythemia vera, and a reduced
plasma volume indicates stress polycythemia.67

RADIONUCLIDE-MEDIATED
LABORATORY STUDIES
Radionuclide-mediated laboratory studies are
known as “in vitro” diagnostic testing, and they are
performed to measure the amount of a specific
radionuclide in body fluid (blood or urine) samples
by laboratory analysis. Feces can also be tested for
radionuclide concentration. The studies include
procedures that determine the ability of the body to
absorb a radionuclide or the ability of the body to
localize the radionuclide.65 Some of the studies
include scanning procedures to obtain immediate or
delayed images of an organ or area of the body. A list
of commonly used radionuclides and their tissue
sites can be found in Table 20–1.

TOTAL BLOOD VOLUME STUDY
The total blood volume study is a nuclear laboratory
test performed to determine the amount of circulating blood volume in the body. It includes a combination of tests for plasma volume and RBC volume
that make up the total volume, although the tests can
be performed individually, depending on the reason
for the study and the needed diagnostic information. The total blood volume is estimated in milliliters (mL) per kilogram (kg) because of the
variations in individual body weight and frame.
Normally, the blood constitutes 6 to 8 percent of
the total body weight. It consists of blood cells
suspended in plasma. Plasma forms 45 to 60 percent
of the total blood volume and the RBCs constitute
most of the remaining volume.66
The test involves the IV administration of the
client’s own RBCs labeled with chromated Cr 51
sodium for RBC volume or human serum albumin
labeled with 125I for plasma volume. After the preparation and reinjection of the radiopharmaceutical,
blood samples are periodically drawn and the
volumes calculated. RBC volume is calculated using

Reference Values
Total blood volume

80–85 mL/kg

RBC volume
Men

25–35 mL/kg

Women

20–30 mL/kg

Plasma volume

30–45 mL/kg

INTERFERING FACTORS

IV administration of fluid or blood replacement
before the study
Dehydration, overhydration, or excessive blood
loss
INDICATIONS FOR TOTAL BLOOD VOLUME
STUDY

Evaluating blood and fluid losses resulting from
hemorrhage, burns, surgery, or dehydration:
Responses include hypotension, increased
pulse, oliguria, or dry skin, leading to shock
state or fluid imbalance.
A sudden reduction in the total blood volume
can lead to shock, whereas a gradual loss can
lead to an increasing plasma volume and
decreasing RBC volume.
Differentiating between stress polycythemia and
polycythemia vera:
RBC volume remains at a normal or reduced
level in stress polycythemia and increases in
polycythemia vera.
Increased RBC volume in combination with
increased WBCs and platelets that occur in
polycythemia lead to stroke, hemorrhage,
myocardial infarction, and venous thrombosis
as the blood becomes more viscous.68
Plasma volume is reduced and hematocrit is
elevated with a normal level of RBC volume in

CHAPTER 20—Nuclear

stress polycythemia, and it remains at a normal
or slightly increased or decreased level in polycythemia vera.
Determining replacement therapy:
In hemorrhage or loss caused by surgery,
gastrointestinal bleeding, or trauma, whole
blood is usually administered.
In reduced RBC volume caused by bleeding or
cell destruction, packed RBC is administered.
In reduced plasma volume caused by bleeding,
burns, or trauma, plasma volume expander is
administered.
In dehydration state, IV fluids of normal saline
or distilled water with or without glucose are
administered.
This test is used before surgical procedures to
anticipate need for replacement therapy and
type of replacement needed.
Monitoring response to replacement therapy
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
test greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any study
involving the collection of a peripheral blood sample
(see Appendix I).
Inform the client of the injection of a radiopharmaceutical and explain that a minute amount of
the material is administered and excreted from
the body within 24 hours without causing any
harmful effects.
Inform the client of the schedule for blood
samples and explain that the venipunctures are
the only discomfort experienced.
Obtain and record client’s height and weight,
because values are calculated and expressed in
milliliters per kilogram.
History should include hematologic system information, assessment of vital signs, and potential
causes of fluctuations.
THE PROCEDURE

Red Blood Cell Volume. The client is placed on the
examining table in a supine position for 30 minutes.
The prepared dose (5 mL) of the labeled radiopharmaceutical is injected into the vein of one arm.
Blood samples (5 mL) are drawn from a vein in the
opposite arm in 10 and 40 minutes after the injection. Normally, these samples are equal in counts,
but if there is a delay in equal readings caused by
splenomegaly or polycythemia, the reading at 40
minutes is more accurate. A 2-mL sample is taken
from the 5-mL sample and counted. A microhemat-

Scan and Laboratory Studies

517

ocrit is performed to assist in a polycythemia diagnosis. The blood samples are counted to determine
the concentration of the radionuclide and compared
with the amount administered to obtain the volume
of RBCs.
Plasma Volume. The client is placed on the examining table in a supine position for 30 minutes. A
blood sample (5 mL) is drawn and centrifuged, and
2 mL is removed to perform a count and establish a
standard. The radiopharmaceutical is injected into
one arm, and in 10 minutes a blood sample is drawn
from the opposite arm. The sample is centrifuged,
and 2 mL of plasma is removed and counted. Plasma
volume is determined by comparing the counts from
the sample with the established count standard.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test are the same as for
any study involving a venipuncture for injection or
collection of a peripheral blood sample (see
Appendix I).
Assess vital signs and compare them with pretest
readings. Continue to monitor if total blood
volume falls below 80 mL/kg.
Monitor ordered replacement therapy such as
blood or blood component transfusion or IV
fluids.
Monitor intake and output to prevent or assist in
controlling blood or fluid loss or overload, or
both.
Provide support when diagnostic findings are
revealed, especially if continuing treatment is
necessary, as in polycythemia vera (phlebotomy
every 2 to 3 months, myelosuppressive drug therapy to reduce bone marrow activity).

RED BLOOD CELL SURVIVAL TIME
STUDY
An RBC survival time study is a nuclear laboratory
test performed to determine whether an anemic
state is caused by a decrease in the survival of RBCs.
Normally, RBCs have a life span of 120 days, with 0.8
percent loss per day and a half-time of 60 days. The
normal half-time, which serves as a basis for determining the rate of survival or destruction in this
study, is 25 to 35 days for this test because of an additional loss of tagging from RBCs.69 When the RBCs
are destroyed or sequestered in the spleen, the life
span of the cells is reduced and a diagnosis of
hemolysis can be made as a cause of anemia. The
study is performed in combination with RBC
volume and iron studies (see Chapter 1).
The test involves two stages. The first stage

518

SECTION II—Diagnostic

Tests and Procedures

Reference Values
Survival Time
Normal life span of RBCs 120 days, with a normal loss of 0.8% per day
Normal half-time of RBCs 60 days
Normal half-time of labeled RBCs 25–35 days
Splenic Sequestration
Spleen-to-liver ratio 1:1
Spleen-to-pericardium ratio 2:1 or less

provides laboratory testing of blood after the injection of a specially prepared radiopharmaceutical.
The client’s own blood is drawn and labeled with
chromated Cr 51 sodium and reinjected. Scheduled
blood samples are drawn daily to test for blood levels
of radioactivity in the circulation. The second stage
provides for a scanning of the spleen to determine
whether the reduced life span of the RBCs is caused
by splenic sequestration. The liver and pericardium
are also scanned to determine pathogenic mechanisms. Counts are made for each area and a ratio is
established for spleen to liver and spleen to pericardium to determine splenic abnormalities,
because a rising ratio indicates sequestration significant to RBC destruction.
INTERFERING FACTORS

Recent transfusion or hemorrhage falsely
decreases RBC survival.
High WBC and platelet counts falsely decrease
RBC survival time.
INDICATIONS FOR RED BLOOD CELL SURVIVAL
TIME STUDY

Known or suspected hemolytic anemia conditions
causing a decreased survival value:
Intrinsic or extrinsic defects listed in Table
20–2
Identification of the need for further studies to
confirm diagnosis of intrinsic or extrinsic
defects causing the anemia
Known or suspected disorders causing an
increased survival of RBCs as revealed by more
than a 35-day survival value:
Erythrocytosis caused by primary or secondary
polycythemia or thalassemia minor
Chronic hypoxia, respiratory or cardiovascular
disease, high altitudes, hypoventilation
syndromes, and renal disorders, which can
stimulate production of RBCs

Determination of RBC sequestration in the spleen
as revealed by a spleen-to-liver or spleen-to-pericardium ratio:
Differentiation between splenomegaly, as
revealed by an increased spleen-to-liver ratio
with a normal spleen-to-pericardium ratio, and
sequestration, as revealed by an increased
spleen-to-liver ratio of 2:1 to 4:1 over the entire
study period or a spleen-to-pericardium ratio
of more than 2:170
Provision of guidance for treatment (splenectomy) that removes the source of RBC destruction, resulting in a prolonged RBC survival
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
study greatly outweigh the risks to the fetus
Excessive bleeding or clotting abnormality
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any study
involving the collection of a peripheral blood sample
(see Appendix I) and any nuclear laboratory study
(see section under “Brain Scanning”).
Instruct the client in collection and testing of a
stool specimen for occult blood if this part of the
test is ordered.
History should include a hematologic system
assessment, vital signs, and results of hemoglobin,
hematocrit, platelet, WBC, and reticulocyte
counts.
THE PROCEDURE

Phase 1. A blood specimen of 10 mL is drawn from
the client and centrifuged to remove the plasma. The
remaining cells are labeled and reinjected. A blood
sample is drawn 24 hours after the injection and
then every other day for 3 weeks. Each specimen is
analyzed for counts per minute of the radionuclide
and plotted on graph paper to determine the RBC

CHAPTER 20—Nuclear

TABLE 20–2

Scan and Laboratory Studies

519

Classifications of Hemolytic Anemias

Intrinsic Defects

Extrinsic Defects

Hereditary defects

Nonimmune destruction

Abnormalities of the RBC membrane

Microangiopathic and macroangiopathic
hemolytic anemia

Hereditary spherocytosis

Chemical and toxic agents

Hereditary elliptocytosis

Infections causing hemolysis

Hereditary pyropoikilocytosis

Hypersplenism

Hereditary stomatocytosis and xerocytosis
Inherited erythrocyte enzyme disorders

Systemic disorders
Immune hemolytic anemias

Glucose-6-phosphate dehydrogenase
deficiency

Primary

Other enzyme deficiencies

Secondary (associated with chronic lymphocytic
leukemia, lymphomas, and carcinomas)

Pyruvate kinase deficiency

Drug induced

Pyrimidine-5′-nucleotidase deficiency

Infections

Disorders of hemoglobin production
Hemoglobinopathies
Sickle cell syndromes
Sickle cell disease
Sickle cell trait
HbS -thalassemia syndrome
Hemoglobin C disease
Hemoglobin SC disease
Methemoglobins/hemoglobin M
Unstable hemoglobin
Thalassemia syndromes
-Thalassemia
Homozygous -thalassemia
Heterozygous -thalassemia
Thalassemia heterozygotes with other
hemoglobinopathies
Acquired defects
Paroxysmal nocturnal hemoglobinuria
From Sacher, RA, and McPherson, RA: Widmann’s Clinical Interpretation of Laboratory Tests, ed 10. FA Davis,
Philadelphia, 1991, p 94, with permission.

survival half-time. The rate at which the labeled cells
disappear during the timed testing indicates the
progression of cell destruction.
Phase 2. Scanning of the spleen, liver, and pericardium is performed on the same schedule as for

phase 1 in conjunction with the RBC survival study.
Splenic sequestration is determined by the concentration of the radionuclide at the site of cell damage.
To determine splenic abnormalities, counts are
performed for each area and spleen-to-liver and
spleen-to-pericardium ratios are established.

520

SECTION II—Diagnostic

Tests and Procedures

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the tests are the same as
for any study involving a venipuncture for injection
or collection of a peripheral blood sample (see
Appendix I).
If scanning is performed, care and assessment are
the same as for any nuclear scan study (see section
under “Brain Scanning”).
Monitor vital signs and compare them with
pretest readings.
Monitor ordered replacement therapy in severe
anemic state (packed RBC, IV fluids).
Assess for fatigue or activity intolerance when
RBC survival is decreasing, and provide rest and
measures to preserve energy.
Assess for jaundice, adequate hydration, and pain
in anemic state when RBC survival is decreasing.
Assess for hypoxic states when RBC survival rate
is increasing and provide oxygen, if needed.
Assess for ability to follow instructions for return
to the laboratory for blood tests and scanning.
Provide a written schedule.
Provide support when diagnostic findings are
revealed, especially if a congenital or chronic
disorder is diagnosed, and assist in coping with
the chronicity or life-threatening risk associated
with an increase or decrease in RBC survival rate.

PLATELET SURVIVAL TIME STUDY
Platelet survival time study is a nuclear laboratory
test performed to measure the life span of circulating platelets to assist in the diagnosis of conditions
involving vascular integrity and hemostasis. Platelets
are formed in the bone marrow and have a normal
life span of 9 days. Disappearance of the platelets
from the circulating blood depends on their destruction by the reticuloendothelial system. If the platelet
survival time is decreased, a proportional decrease in
the platelet count is generally seen. Within the few
days of continuing platelet destruction, platelet
production can increase to two to eight times its
normal rate. If the production rate does not
compensate for the increased rate of destruction,
thrombocytopenia will persist. Many conditions
reflect a diminished platelet survival time, most
commonly, diabetes, vascular disorders, cirrhosis,
and idiopathic thrombocytopenic purpura (ITP).
The test involves the labeling of the client’s own
platelets with chromated Cr 51 or indium In 111
chloride. The labeled material is reinjected IV and
blood samples are drawn over a period of days. The
number of platelets and their progressive reduction
in numbers are determined by testing the samples

and formulating a curve over the scheduled testing
days. Nonlinear curve shapes indicate a pathological
condition causing destruction of the platelets.
Scanning can also be performed to diagnose vascular abnormalities such as thrombosis or embolism.
INTERFERING FACTORS

IV administration of fluid or volume expanders
before the study
Large emboli that obstruct an artery and prevent
the emboli from being exposed to the radionuclide in the blood
Heparin, which can prevent visualization of an
embolus
Therapy with drugs known to alter platelet
survival, unless the test is performed to evaluate
the effects of such drugs
INDICATIONS FOR PLATELET SURVIVAL
TIME STUDY

Disorders that increase or decrease levels by
reduced production or increased destruction of
platelets (see Chapter 2, Table 2–6).
Non-immune-mediated disorders associated with
reduced platelet survival:
Disseminated intravascular coagulation associated with shock, severe crush and burn injuries,
surgical trauma, tissue infarction, overwhelming sepsis, and the obstetric complication of
abruptio placentae
Consumptive coagulopathy associated with
vascular injury such as thrombotic thrombocytopenic purpura, hemolytic-uremic syndrome,
and vasculitis71
Prosthetic heart valves
Arterial grafts
Renal transplantation
Peripheral vascular disease
Hepatic cirrhosis
Post-transfusion purpura or use of extracorporeal circulation during surgery
Immune-mediated disorders associated with
reduced platelet survival:
ITP, as revealed by extremely short platelet
survival measured in minutes to hours, chronic
lymphocytic leukemia, lymphomas, systemic
lupus erythematosus, and isoimmune neonatal
thrombocytopenia
Drug sensitivity reactions from heparin,
quinine, sulfonamide derivatives, gold salts,
digitoxin, or thiazides
Diagnosis and location of DVT revealed via
imaging
Diagnosis of pulmonary embolism revealed by
visualization through imaging of the adherence

CHAPTER 20—Nuclear

Scan and Laboratory Studies

521

Figure 20–1. Normal platelet
survival. (Adapted from Thompson, AR and Harker, LA: Manual
of Hemostasis and Thrombosis,
ed 3. FA Davis, Philadelphia, p
18, 1983.)

of the radionuclide to the emboli, although not
a very sensitive test for older thrombi in the
lung because adherence is reduced with aging72
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
study greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any study
involving the collection of peripheral blood samples
(see Appendix I) and nuclear laboratory tests:
History should include information about the
hematologic status, assessment of vital signs, and
results of reticulocytes, WBC, platelet counts, and
hemoglobin level.
THE PROCEDURE

A blood specimen is drawn from the client and
centrifuged to produce platelets containing plasma.
The platelets are labeled with the radioactive
substance and reinjected into the client’s other arm.
Blood samples are drawn in 48 hours and daily
thereafter for 7 to 8 days. The amount of radionuclide is measured as it disappears from the circulation; this process is related to age destruction of the
platelets. A graph is plotted using the number and
time of platelet destruction over a period of scheduled testing days (Fig. 20–1). Imaging for DVT and
pulmonary embolism can take place immediately or
can be delayed to determine the degree of uptake in
the affected areas.73 The scanning phase is reserved
for these conditions and is not to determine platelet
destruction.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test are the same as for

any study involving a venipuncture for injection
or collection of a peripheral blood sample (see
Appendix I).
If scanning is performed, care and assessment are
the same as for any nuclear scan study (see section
under “Brain Scanning”).
Immediately report platelet count of less than
20,000 per L, considered a critical level, if this
laboratory test is performed.
Assess for bleeding and blood loss from mucous
membranes, skin (petechiae, ecchymoses, epistaxis, feces, hematuria, hematemesis, or hemoptysis) with thrombocytopenia.
Provide measures to prevent bleeding with
thrombocytopenia (gentle handling, trauma
protection, soft toothbrush, or electric razor).
Monitor ordered platelet infusion for treatment of
thrombocytopenia.
Monitor ordered anticoagulant therapy if thrombosis or embolus is diagnosed.
Resume ordered administration of corticosteroid
therapy for thrombocytopenia.
Provide a written schedule for return to the laboratory and nuclear medicine department for testing or scanning, or both.
Provide support when diagnostic findings are
revealed, and assist client to cope with chronicity
of a disease and the need for repeated testing and
long-term therapy.

RADIOACTIVE IODINE UPTAKE STUDY
Radioactive iodine uptake (RAIU) study is a nuclear
laboratory test performed to evaluate thyroid function. Its primary value is in its ability to assist in
diagnosing hyperthyroidism, because the radionuclide is readily concentrated in the thyroid gland.

522

SECTION II—Diagnostic

Tests and Procedures

The radionuclide 123I is administered orally, followed
by scanning of the thyroid area. Clients with hyperthyroid conditions reveal an increased uptake of the
radionuclide. The test is not as effective in the diagnosis of hypothyroidism. Uptake is expressed in
percentages of radionuclide absorbed in a specific
amount of time. This percentage is calculated by
dividing the amount of uptake by the amount or
dose administered. An increase of more than 35
percent in 24 hours indicates hyperthyroidism.74
The test is usually performed in combination with
thyroid hormone tests when other thyroid function
studies do not provide a definitive diagnosis.
Reference Values
2-hr Absorption 1–13% of radionuclide
6-hr Absorption 6–15% of radionuclide
24-hr Absorption 8–30% of radionuclide
INTERFERING FACTORS

Recent use of iodinated contrast media for radiographic studies, which would decrease the
uptake of the radionuclide
Ingestion of foods containing iodine or medications containing iodine, such as cough syrup,
potassium iodide, vitamins, Lugol’s solution, or
thyroid replacement therapy, which would decrease the uptake of the radionuclide
Medications such as propylthiouracil, corticosteroids, warfarin, antihistamines, sulfonamides,
nitrates, tolbutamide (Orinase), or isoniazid,
which would decrease the uptake of the radionuclide
Severe diarrhea, which would affect absorption of
the radionuclide dose
Lithium, estrogen, TSH, barbiturates, and
phenothiazines, which would increase the uptake
of the radionuclide
Iodine-deficient conditions, cirrhosis, or renal
failure, which would increase the uptake of the
radionuclide
INDICATIONS FOR RADIOACTIVE IODINE
UPTAKE STUDY

Evaluating thyroid function:
A response of increased uptake of 20 percent
absorption in 1 hour, 25 percent in 6 hours,
and 45 percent in 24 hours indicates hyperthyroidism.75
A response of decreased uptake of 0 to 10
percent over a 24-hour period indicates a
hypothyroid state but not necessarily hypothy-

roidism because of the many interfering factors
reducing the uptake.
Monitoring response to therapy for thyroid
dysfunctional states
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
study greatly outweigh the risks to the fetus
Sensitivity to iodine in foods or medications
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any nuclear
laboratory test (see section under “Total Blood
Volume Study”) and nuclear scan study (see section
under “Brain Scanning”).
Inform the client of the scanning schedule and
explain that the study can take 24 hours.
Instruct the client to restrict any iodine-containing foods and medications for at least 1 week
before the study.
Withhold all foods and fluids for 8 to 12 hours
before the study, according to department policy.
History should include previous thyroid studies,
allergies to iodine, medication regimen, and
results of thyroid hormone tests.
THE PROCEDURE

The client is given the radionuclide orally, unless a 2hour scan is to be performed, which requires IV
administration. The client is placed on the examining table in a supine position with the neck slightly
hyperextended on a small pillow. The client is then
requested to remain still during the procedure. The
scanning is performed with a detector over the neck
in 30 minutes to determine the gland’s ability to take
up the radionuclide, in 6 hours to determine the
gland’s ability to bind iodine, and in 24 hours to
determine the gland’s total uptake of the radionuclide. Subsequent imaging can be performed for
information about the gland’s ability to release the
radionuclide.76 Determination of the percentage of
uptake is calculated using the amount of the dose
and the amount absorbed in a specific time period.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”) and venipuncture for
injection of the radionuclide (see Appendix I).
Assess for fatigue, nervousness, increased
appetite, increased sweating, or weight loss
common in hyperthyroidism and caused by
increased metabolic activity.
Resume normal dietary intake and thyroid
replacement therapy.

CHAPTER 20—Nuclear

Resume medication regimen if iodine-containing
drugs have been withheld before the study.
Provide a written schedule for the client’s return
to the department for scanning.

THYROID-STIMULATING HORMONE
STUDY
TSH study is a nuclear laboratory test performed to
measure thyroid gland response to the administration of a dose of TSH. The test involves the administration of TSH intramuscularly (IM) followed by an
IV injection of iodide I 123 and scanning to determine the effect of TSH on thyroid gland uptake of
the radionuclide.77 It is performed in combination
with the radioactive iodine uptake study to differentiate between primary and secondary hypothyroidism. TSH, also known as thyrotropin, is
produced by the basophil cells of the adenohypophysis in response to stimulation by its hypothalamic
releasing factor, thyrotropin-releasing hormone
(TRH). Primary hypothyroidism that results from
thyroid pathology does not respond to the TSH
dose, whereas secondary hypothyroidism, resulting
from an abnormally reduced stimulation by the
pituitary gland secreting the TSH, causes a positive
response to the TSH dose. Thyroid and pituitary
glands therefore can both be evaluated with this test.
Reference Values
Less than 10 U/mL of TSH
Increase in TSH levels, thyroxine (T4), and
radioactive iodine uptake by 8 hr after administration of TSH
INTERFERING FACTORS

Recent radionuclide scanning, which can affect
uptake
Foods or medications containing iodine, which
can decrease uptake of iodine
Aspirin, heparin, dopamine, or corticosteroids,
which can decrease levels of TSH
INDICATIONS FOR THYROID-STIMULATING
HORMONE STUDY

Evaluating thyroid function to differentiate
between primary and secondary hypothyroidism:
TSH level decreased in secondary hypothyroidism (hypothalamic or pituitary gland
source) as revealed by near 0 levels with a low
T4 level because TSH cannot be secreted
TSH level increased in primary hypothyroidism (Hashimoto’s thyroiditis, congenital

Scan and Laboratory Studies

523

disorders, thyroidectomy, radioactive therapy)
as revealed by TSH level greater than three
times the normal range and a decreased T4
level, causing a compensatory rise in TSH
Diminished uptake of the radionuclide in
RAIU study at all intervals in hypothyroidism
Monitoring response to thyroid hormone therapy
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any nuclear
laboratory test (see section under “Total Blood
Volume Study”) and nuclear scan study (see section
under “Brain Scanning”).
Inform the client of the scanning schedule and
explain that the hormone is administered IM by
the physician twice during the study.
Inform the client that a counterscanner is placed
over the region of the thyroid gland each time in
the series that the test is performed.
THE PROCEDURE

The client is given 10 units of TSH by IM injection
by the physician and placed on the examining table
in a supine position with the head slightly hyperextended on a small pillow. Counts are taken over the
thyroid gland, followed by the IM injection of
another 10 units of TSH and the oral administration
of the radionuclide for the RAIU scan. An uptake
and scan are performed in 2 to 6 hours and again 24
hours later. Refer to the radioactive iodine uptake
scan procedure (see preceding section) and thyroxine laboratory test (see Chapter 5, “Thyroxine”
section) for further information about this test.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any nuclear scan study (see section
under “Brain Scanning”) and venipuncture for
injection of the radionuclide (see Appendix I).

THYROID CYTOMEL/PERCHLORATE
SUPPRESSION STUDIES
Thyroid Cytomel (liothyronine) and perchlorate
suppression studies are nuclear laboratory tests
performed to determine thyroid function. Cytomel
suppression is performed to assist in diagnosing
goiter disease and borderline hyperthyroidism. It
involves the administration of triiodothyronine
followed by scanning for 123I or 131I uptake, revealing the effect of suppression or the absence of

524

SECTION II—Diagnostic

Tests and Procedures

suppression. Normally, uptake decreases more than
60 percent when compared with an initial scan.
Hyperthyroidism evaluated in this test is caused by
Graves’ disease (toxic goiter), an autoimmune
disease causing antibodies to bind to thyroid cells,
resulting in glandular hypertrophy and the secretion
of thyroid hormone. It can also be caused by
Plummer’s disease (multinodular goiter), resulting
in an increased gland size and progressively developing hyperthyroidism or a solitary hyperfunctional
adenoma (toxic adenoma) that is multinodular and
produces hyperthyroidism. This test has generally
been replaced by the TRH stimulation test.
Perchlorate suppression is performed to assist in
diagnosing organification defects responsible for
hypothyroidism, a term used to indicate a
hypometabolic state caused by deficient thyroid
secretions. The test involves measurement of thyroid
gland activity after scanning for 131I uptake and
subsequent admission of potassium perchlorate.
Abnormal findings reveal a fall in uptake in 2 hours
when compared with uptake after the perchlorate
intake. The counts and timing of the uptake are
displayed on a graph from which thyroid activity is
calculated.78
Reference Values
Cytomel suppression: 50% depression of thyroid
uptake after liothyronine (T3) administration
Perchlorate suppression: Absence of change in
thyroid uptake after perchlorate administration

INTERFERING FACTORS

Foods and medications containing iodine taken
before the study
INDICATIONS FOR THYROID CYTOMEL/
PERCHLORATE SUPPRESSION STUDIES

Cytomel Suppression
Evaluation of the effect of T3 on thyroid uptake of
the radionuclide in the diagnosis of thyroid function:
Uptake is increased initially and decreases after
Cytomel in thyroiditis, deficient iodine, or
other hormone abnormality. Decrease can be
more than half of the baseline level.
Uptake is increased initially, and no change is
demonstrated after Cytomel in Graves’ disease,
Plummer’s disease, and toxic adenoma.
Suppression is absent in borderline hyperthyroidism.

Diagnosis of thyroid pathology that causes
changes in uptake after Cytomel and subsequent
suppression:
Suppression is absent if nodules are present.
Slight suppression is absent if thyroid malignancy is present.
Absence of changes in uptake after thyroid therapy that causes destruction of tissue
Perchlorate Suppression
Diagnosis of thyroid disorders that reveal changes
in the organification process that causes decreases
in uptake of the radionuclide:
Congenital hypothyroidism in infants with a
decrease of at least 15 percent in uptake after
perchlorate indicates a congenital enzyme deficiency (peroxidase) within the gland as
perchlorate removes unbound iodine and
prevents further uptake.
Decrease in uptake after perchlorate in
Hashimoto’s thyroiditis is commonly found in
autoimmune diseases such as lupus erythematosus and rheumatoid arthritis, as well as
pernicious anemia and Addison’s disease,
because iodine is prevented from being
concentrated by the thyroid and unbound
iodide is prevented from being released.
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any nuclear
scan study (see section under “Brain Scanning”).
Cytomel Suppression. Instruct the client to take
ordered 25 mg of Cytomel every 8 hours for 5 to 10
days, explain the schedule, and ask the client to
return to the department for the scanning.
Inform the client that foods and medications
containing iodine should be restricted before the
test.
Explain that a radionuclide is administered IV
and that some discomfort will be experienced at
that time but that this is the only discomfort experienced during the test.
History should include previous thyroid tests,
allergies to iodine, medication regimen, and other
therapy.
Perchlorate Suppression. Preparation is the same
as for Cytomel suppression except that food and
fluids are withheld 8 to 12 hours before the test and
foods and medications containing iodine are with-

CHAPTER 20—Nuclear

held for at least 1 week before the test. The client can
be given a list of foods and medications to avoid.
Inform the client that the radionuclide is administered orally instead of IV and that the perchlorate is
given orally during the test.
THE PROCEDURE

The procedure for radioactive iodine uptake is
found in the preceding section.
Cytomel Suppression. The client comes to the
nuclear medicine department 1 day before the last
dose of Cytomel. Scanning is performed at that time
and residual uptake is recorded. The radionuclide
123
I or 131I is administered, and scanning is then
performed 2 and 6 hours later.
The client is requested to return to the department after the last dose of Cytomel and an additional uptake scan is performed. Uptakes are
compared, and increases or other changes are determined, based on the dose of the radionuclide, the
timing of the medications, and scanning.
Perchlorate Suppression. Scanning is performed to
determine whether any residual radionuclide is present. The radionuclide is administered orally, and
scanning for uptake is performed in 1 and 2 hours.
After the 2-hour measurement, 1 g of perchlorate is
given orally, as this dose is trapped by the thyroid
and displaces the iodide that has not been organified. Uptakes obtained by scanning are then
performed every 15 minutes for 90 minutes.
Additional scanning can be performed every 30
minutes for the next 2 hours. Uptakes after the
perchlorate and those performed 2 hours before the
perchlorate are compared and results graphed, based
on time of uptakes, amount of the radionuclide
concentrated in the thyroid gland, or absence of it in
the gland.

Scan and Laboratory Studies

525

ileum. Absorption of this vitamin requires that it be
bound to intrinsic factor, a glycoprotein secreted by
the gastric mucosa. Pernicious anemia, the most
common and severest form of vitamin B12 deficiency, involves a deficiency of intrinsic factor, which
reduces absorption of the vitamin in the ileum.
Intestinal malabsorption syndrome, pancreatic
disorders, and medications can also cause this vitamin deficiency.
The test involves the oral administration of a
capsule of vitamin B12 labeled with the radioactive
substance cobalt as cyanocobalamin Co 57 to determine gastrointestinal absorption of the vitamin. An
injection of a nonradioactive vitamin B12 can be
given in addition to the oral dose to enhance saturation of binding sites, intestinal absorption, and renal
excretion of the radionuclide. A 24-hour urine specimen is then collected. Test results are expressed as
the percentage of radionuclide excreted in the urine
in relation to the amount administered. If less than 5
to 15 percent of the radionuclide is excreted, a twostage test is indicated. For the second phase, an oral
dose of intrinsic factor is given in addition to the
labeled and unlabeled doses of the vitamin. If subsequent excretion of vitamin B12 reaches normal
levels, pernicious anemia is confirmed; if not,
malabsorption syndrome is present.79
Reference Values
Normally, 15–40% of a 0.5-mg dose and 5–40% of
a 1.0-mg dose of radioactive vitamin B12
excreted
Less than 7% of the smaller dose and 0–3% of the
larger dose excreted in impaired absorption
states
INTERFERING FACTORS

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedures are the
same as for any nuclear scan study (see section
under “Brain Scanning”).
Resume normal dietary intake and medication
regimen.
Provide a written schedule for return to the
department for scanning and test completion.

SCHILLING TEST
The Schilling test is used to determine the cause of a
vitamin B12 deficiency, which can result from lack of
intrinsic or extrinsic factors or malabsorption in the

Recent diagnostic tests with radioactive materials
Incomplete collection of the timed urine sample
Laxatives before the test that impair intestinal
absorption of the vitamin B12
INDICATIONS FOR SCHILLING TEST

Identification of deficiency of vitamin B12
absorption (one-stage test)
Determination of the cause of vitamin B12 deficiency by differentiating between pernicious
anemia and gastrointestinal malabsorption problems:
In pernicious anemia, urinary excretion of B12
approaches normal levels when intrinsic factor

526

SECTION II—Diagnostic

Tests and Procedures

is administered as part of the study (two-stage
test).
In gastrointestinal malabsorption, urinary
excretion of B12 is decreased.
Nursing Alert

Urine collection time can be prolonged to 48
to 72 hours in clients with severe renal
disease. The normal percentage of the labeled
vitamin B12 will eventually be excreted,
however, as long as the client does not have
impaired vitamin B12 absorption.
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
procedure greatly outweigh the risks to the fetus
NURSING CARE BEFORE THE PROCEDURE

Client preparation is the same as for any nuclear
laboratory study (see section under “Total Blood
Volume Study”).
Inform the client that a radioactive vitamin B12 is
administered orally and a nonradioactive vitamin
B12 is administered IM for the test and that the
substances are eliminated from the body without
harmful effects.
Advise the client that food and fluid are withheld
for 8 hours and that laxatives should be avoided
for at least 2 days before the study.
Provide a schedule for both administrations of the
B12 and for urine collection, and provide a
container to collect the urine.
Inform and instruct the client in the collection of
the urine specimen, including the length of time
(usually 24 hours), care of the special container,
importance of saving all the urine, and avoidance
of contamination with feces or toilet tissue (see
Appendix II).
History should include information about hematologic and gastrointestinal status, results of
folate, total binding capacity, B12 blood tests, and
signs and symptoms of anemia or malabsorption.
THE PROCEDURE

One-Stage Test. The client voids and the urine is
discarded. If a radionuclide study has been
performed recently, a sample of the urine to be
discarded can be sent to the laboratory for radioactivity residual. A 0.5- to 1.0-mg capsule of labeled
vitamin B12 is administered orally. This dose is
followed by an IM dose of 1000 mg of unlabeled B12
1 to 2 hours later (depending on laboratory preference). Foods and fluids can be resumed after the IM

injection. All urine is collected for 24 hours in a
container without a preservative (48 to 72 hours in
those with renal disease) and sent to the laboratory
for analysis (see Appendix II). When absorption is
normal, vitamin B12 in excess of body needs is
excreted by the kidneys. If absorption is impaired,
the vitamin either does not appear in the urine or is
found in only limited amounts. The unabsorbed B12
is excreted in the feces.
Two-Stage Test. The client voids and the urine is
discarded. If the test is performed on the day after a
one-stage test, a specimen from the first morning
voiding should be checked by the laboratory for
persistent radioactivity. A 0.5- to 1.0-mg capsule of
labeled vitamin B12 is administered orally. The client
can then eat breakfast, after which a 60-mg dose of
intrinsic factor is administered orally. In 1 to 2
hours, an IM dose of 1000 mg of unlabeled vitamin
B12 is administered (“flushing dose”). This dose
competes with the absorbed radioactive material for
binding sites and allows excretion of the radioactive
B12 in the urine. All urine is collected for 24 hours in
a container as in the one-stage test. Findings are
based on the amount of B12 excreted in the urine
over a specific period.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test are the same as for
any nuclear laboratory test (see section under “Total
Blood Volume Study”).
Resume normal dietary intake.
Assess for fatigue, weakness, sore tongue,
anorexia, vomiting, or abdominal pain indicating
pernicious anemia.
REFERENCES
1. Berkow, R (ed): The Merck Manual, ed 16. Merck Sharp and
Dohme Research Laboratory, Rahway, NJ, 1992, p 2548.
2. Ibid, pp 2548–2549.
3. Corbett, JV: Laboratory Tests and Diagnostic Procedures with
Nursing Diagnoses, ed 3. Appleton & Lange, Norwalk, Conn, 1992,
p 552.
4. Berkow, op cit, p 2164.
5. Ibid, p 2549.
6. Pagana, KD, and Pagana, TJ: Mosby’s Diagnostic and Laboratory
Test Reference. Mosby–Year Book, St Louis, 1992, p 575.
7. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed 4.
JB Lippincott, Philadelphia, 1992, p 609.
8. Ibid, p 622.
9. Corbett, op cit, p 543.
10. Fischbach, op cit, pp 569–570.
11. Ibid, p 609.
12. Ibid, p 569.
13. Berkow, op cit, p 2550.
14. Corbett, op cit, p 556.
15. Datz, FL: Nuclear Medicine. Mosby–Year Book, St Louis, 1988, p
51.
16. Pollycove, M: Nuclear Medicine Manual. San Francisco General
Hospital, San Francisco, 1990.
17. Pagana and Pagana, op cit, p 124.

CHAPTER 20—Nuclear

18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.

Fischbach, op cit, p 579.
Ibid, p 579.
Datz, op cit, pp 82–83.
Ibid, pp 76–78.
Ibid, pp 78–79.
Ibid, pp 284–285.
Ibid, pp 289–296.
Ibid, pp 42–43.
Ibid, pp 38–39.
Ibid, pp 39–40.
Pagana and Pagana, op cit, p 161.
Fischbach, op cit, p 583.
Ibid, pp 256, 263–269.
Ibid, p 586.
Ibid, p 584.
Datz, op cit, p 243.
Ibid, p 108.
Ibid, p 122.
Pagana and Pagana, op cit, p 489.
Datz, op cit, p 115.
Ibid, pp 5–6, 132.
Berkow, op cit, p 2550.
Ibid, p 8.
Datz, op cit, p 36.
Ibid, pp 274–277.
Ibid, pp 161–164.
Corbett, op cit, p 562.
Datz, op cit, p 170.
Ibid, pp 168–169.
Ibid, pp 172–173.
Ibid, p 165.
Ibid, p 165.
Ibid, p 165.

51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
78.
79.

Scan and Laboratory Studies

527

Berkow, op cit, pp 801, 2551.
Datz, op cit, pp 138–139.
Ibid, pp 152–153.
Pagana and Pagana, op cit, pp 351–352.
Ibid, p 352.
Ibid, pp 352–353.
Ibid, p 358.
Datz, op cit, p 155.
Corbett, op cit, p 565.
Datz, op cit, pp 216–218.
Ibid, pp 200–217.
Pagana and Pagana, op cit, p 636.
Springhouse Corporation: Nurse’s Reference Library, Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986.
Datz, op cit, p 225.
Fischbach, op cit, p 609.
Sacher, RA, and McPherson, RA: Widmann’s Clinical
Interpretation of Laboratory Tests, ed 11. FA Davis, Philadelphia,
2000, p 21 .
Datz, op cit, pp 303–304.
Ibid, p 301.
Ibid, p 300.
Pagana and Pagana, op cit, p 624.
Sacher and McPherson, op cit, pp 224–226.
Datz, op cit, p 283.
Ibid, pp 280–283.
Corbett, op cit, p 567.
Fischbach, op cit, p 616.
Pagana and Pagana, op cit, p 612.
Fischbach, op cit, pp 617–618.
Datz, op cit, pp 9–10.
Sacher and McPherson, op cit, p 40.

CHAPTER

Non-Nuclear
Scan Studies
PROCEDURES COVERED
Body Scanning, 530
Head and Intracranial Scanning, 531
Neck and Spinal Scanning, 533
Thoracic Scanning, 534
Abdominal Scanning, 535
Pelvic Scanning, 536

Body MRI, 537
Angiography MRI, 539
Abdominal MRI, 540
Head and Intracranial MRI, 541
Heart and Chest MRI, 541
Musculoskeletal MRI, 542

INTRODUCTION

Non-nuclear scan studies include computed tomography and magnetic
resonance imaging, neither of which uses radiopharmaceuticals and the detectors or devices
that are needed to count or image the uptake of these substances by body tissues. Each procedure uses a special machine and scanning system. Both use computer-generated images on a
screen for viewing and recording.
Non-nuclear scan procedures are not considered invasive and a signed informed consent
form is not required for diagnostic computed tomography unless a contrast medium is used. A
signed consent is required for MRI procedures. The studies are performed by physicians or
trained technicians on inpatients or outpatients in a specially equipped room in or near the
radiology department in a hospital. The results are interpreted by physicians with special education and expertise in such procedures.

COMPUTED TOMOGRAPHY
Computed tomography (CT), also known as
computed axial tomography or computed transaxial
tomography, is a noninvasive procedure that uses
tomographic radiography (x-ray) combined with a
special scanning machine, detectors that determine
the amount of radiographic beams absorbed by
tissues, and a computer that processes these readings
and reconstructs a body region by calculating the
differences in tissue absorption of the radiographic
beams. It produces a series of three-dimensional,
cross-sectional anatomic views of the tissue struc528

ture of solid organs as well as differences between
soft tissue and water. Imaging can also reproduce
sagittal, horizontal, and coronal planes of tissue for
viewing. The procedure was originally developed to
identify brain abnormalities but has now advanced
to include scans of the entire body, a body region,
and specific body organs. Its most recent use is for
imaging of the heart movements and blood flow to
the brain.1 It is primarily performed to assist in the
diagnosis of tumors and inflammatory disorders,
although the CT scan study can produce views of
many types of tissue pathology by allowing differentiation from normal tissue.

CHAPTER 21—Non-Nuclear

The CT scanner uses varying motions and techniques as the beam sweeps across the region to be
imaged and records measurements of the radiation
that is transmitted. The recordings are converted
into digital form and entered into the computer,
where they are processed, displayed on the screen,
and stored on disks for future review. Displays on
the screen provide a view of an area that is divided
into slices that allow a clear picture of the relationships of the structures shown in the slices.2
Identification is made of tissues on the screen based
on higher or lower densities, which appear on the
screen as patterns of shading; for example, bone
appears as white, air appears as black, and soft tissue
appears as shades of gray.
Iodinated or barium contrast media can be
administered before and during the procedure to
further clarify or enhance unusual findings, that is,
tissue density, differentiation of a specific organ
from other structures, or identification of small
tumors.3 Special contrast preparations made for CT
scanning (that contain less iodine, are water soluble,
and contain lower density barium in a solution) are
administered for examination of specific regions or
organs of the body.
The advantage of CT, even though it is more
costly than other types of diagnostic studies, is that
it provides an excellent, clear, and detailed image of
structures not visible with other studies. This allows
earlier diagnosis and treatment and more efficient
follow-up of treatments and postoperative complications. It can also eliminate the need for more invasive procedures such as angiography. A disadvantage
of performing CT studies is their higher cost, especially if adequate results can be obtained by less
expensive procedures. Another disadvantage is the
length of time the client is exposed to radiation, even
though more recent CT equipment has reduced the
amount of radiation required for the study or allows
the study to be completed in less time. Risks are also
involved with the use of contrast media in clients
with sensitivities to the materials and in pregnant
women, because radiation can have an adverse effect
on the developing fetus.

MAGNETIC RESONANCE
IMAGING
Magnetic resonance imaging (MRI), also known as
nuclear magnetic resonance imaging, is a noninvasive procedure that uses a magnet, radio waves to
create a field of energy, and a computer that allows
visualization of a body region. The use of the word
nuclear has been generally excluded to reduce the
anxiety provoked by the term that is often present in

Scan Studies

529

clients needing this study.4 The study produces
cross-sectional, multiplanar images of the entire
body, a body part, and specific body organs. It is
primarily used to assist in the diagnosis of conditions affecting blood flow and in the detection of
tumors, infections, and any other types of tissue
pathology because of its ability to produce images
through bone tissue and fluid-filled soft tissues. It
also allows the study of tissue concentrations of
chemicals (proton spectroscopy) such as sodium,
water, fat, inorganic phosphate, hydrogen ions
(determines pH), and lactate.5
The MRI machine contains a huge magnet in the
scanner that is capable of creating a magnetic field
that causes the nuclei of ions, particularly hydrogen,
in tissues to align themselves in an organized fashion. Hydrogen is the atom measured because it is
found in all tissues of the body and has a high sensitivity to the MRI machine. Radiofrequency energy is
directed to the nuclei, causing the alignment to
become disorganized when the machine is turned on
and then allowing the nuclei to realign themselves
again when the machine is turned off. The radio
signals emitted, which are determined by the nuclei
density, type of specific tissue, and the realignment
time, are processed by the computer. A computergenerated image is then displayed on a screen or a
magnetic tape for immediate and later viewing on a
video monitor.
The greatest advantage of MRI is its ability to
obtain an excellent detailed image of the region
studied without the use of radiopharmaceuticals,
radiologic beams, or administration of a contrast
medium. Its disadvantages are the cost of the study,
the fact that all institutions do not provide this service, and the need for immobilization for long periods to perform the study. Although the study is
considered low risk, pregnant women are not
scanned with MRI, unless the benefits of performing
the study outweigh the unknown risks to the fetus.

COMPUTED TOMOGRAPHY
SCANNING STUDIES
CT scanning studies are imaging procedures of body
parts. The studies are performed to view tissue characteristics and structures of solid organs. They have
many uses and are named for the organ, as in ocular
or renal studies; a region of the body, as in pelvic or
abdominal studies; and body studies, which include
the abdomen, chest, and pelvis, depending on the
reason for the study and the type of diagnostic information needed. The multiple number of images
produced provides a series of detailed views of tissue
density and depth used to determine the presence,

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SECTION II—Diagnostic

Tests and Procedures

location, and extent of pathology; to identify and
locate lesions for guidance of percutaneous fineneedle biopsies; to determine the presence of foreign
bodies and other abnormalities; and to evaluate the
effectiveness of treatments administered to eliminate or ameliorate disease states.

BODY SCANNING
Body scanning is a CT study performed to assist in
diagnosing abnormalities in any part of the body
other than the head, such as the neck, chest,
abdomen, pelvis, spine, and extremities. It can reveal
malignant and benign masses; lymph node enlargement or pathology; and abnormal fluid, blood, or fat
accumulation in organs or cavities. A contrast
medium is administered by mouth, by injection
(intravenously [IV]), or by enema, depending on the
need for initial or additional views to ensure clear
images of specific organs (see the specific body
region scans that follow).6
Scanning provides an immediate image of all
internal parts on a screen as the machine rotates
around the body. All or selected images can be
photographed and preserved for future viewing. The
images define the contours of organs and display
contrast differences as the scanning is performed in
various planes to produce three-dimensional
pictures on a monitor screen.

Determining enlargement of lymph nodes and
retroperitoneal lymphadenopathy in diagnosing
lymphoma
Detecting aortic or abdominal aneurysms
Detecting infections and inflammatory processes,
that is, appendicitis, diverticulosis, pancreatitis,
pneumonitis, inflammatory nodules, abscess of
the liver or other soft tissue
Assessing mediastinum, hilum, and pleura of the
chest to assist in early diagnosis of conditions
affecting these areas
Detecting accumulation of fluid or blood, such as
in ascites, fatty liver, pleural effusion, or hemorrhage
Determining hepatobiliary duct dilation and
determining whether obstruction is present
Determining obstruction of the renal system in
the presence of calculi
Diagnosing congenital anomalies of the renal and
gastrointestinal systems
Measuring bone density in menopausal women
for estrogen replacement in osteoporosis revealed
by an increased density based on calcium levels
Verifying the precise location of a lesion for a CTguided fine-needle biopsy of a mass to eliminate
the need for a surgical procedure to obtain a specimen
Evaluating the effect of medical or surgical interventions on any pathology
CONTRAINDICATIONS

Reference Values
Normal size and contour of body structures and
organs; no pathology such as masses or abnormal accumulation of body fluids or substances

INTERFERING FACTORS

Inability of client to remain still during the procedure
Metallic objects within the examination field,
such as watches or jewelry
Feces, barium, or gas in the gastrointestinal tract
INDICATIONS FOR BODY SCANNING

Diagnosing benign and malignant tumors and
metastasis to other organs such as bone or liver as
revealed by alterations in normal densities in the
various body tissues; that is, reduced density is
darker and increased density is lighter
Diagnosing cysts or nodules in organs, such as in
liver cirrhosis, pancreatic pseudocyst, or renal
cystic disease, revealed by water density in the
presence of cysts

Pregnancy, unless the benefits of performing the
study greatly outweigh the risks to the fetus
Allergy to iodine, if an iodinated contrast medium
is to be used
Extreme obesity
Unstable medical status, including vital signs,
vomiting, increased peristalsis
Extreme claustrophobic response that prevents
client from remaining still while enclosed in the
scanner, unless medications are given before the
study
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure requires from 45 minutes to 2
hours, depending on the extent of the imaging
and whether a contrast medium is used
That foods and fluids are withheld for 4 hours
before the procedure if a contrast medium is used;
otherwise there are no food or fluid restrictions
That medications can be continued, insulin can
be administered, diet can be followed, and study
scheduled around this need
That clothing, including belts, jewelry, and all

CHAPTER 21—Non-Nuclear

metallic objects, is removed and a hospital gown
without snaps or other metallic closures will be
worn
That a contrast medium can be given IV or orally
before the study if better visualization of an area is
desired
That, if a contrast medium is given, nausea, flushing, and sweating experienced after administration should be reported to the physician
That the client is encircled by the scanning camera
during the study while the pictures are taken and
that claustrophobia is not uncommon
That the only discomfort experienced is undergoing the venipuncture to administer the contrast
medium and lying in one position on the hard
table for a long period
Prepare for the procedure:
Administer ordered medications for sedation and
anxiety, such as diazepam (Valium) for claustrophobia, steroids, or antihistamines such as
diphenhydramine (Benadryl) or prednisone
(Deltasone) for known allergies to the contrast
medium before the study.
Have the client void.
If the procedure is closed, known claustrophobia
should be reported to the physician before the
study.
THE PROCEDURE

The client is placed in a supine position on a flat
table within the scanning apparatus after IV or oral
administration of a contrast medium, if this position is appropriate for the views to be obtained. The
client is requested to remain very still because movement results in blurring of the picture. A series of
images are taken while the table is manipulated and
scanning of various levels of the body is performed.
Instructions to hold the breath during the scanning
are given by the technician via an intercommunication system. In some instances, scanning is
performed and the contrast medium administered
with further scanning taking place to enhance visualization of specific areas. The client is advised to
report nausea after the administration of contrast
medium and is instructed to take deep breaths if
nausea occurs. An emesis basin can be made available if needed.
As the scanning takes place, images are immediately portrayed on the screen and recorded on
permanent film. Tissue density and composition of
the organs are demonstrated in white, black, or gray
shades and interpreted by the radiologist.
If the study is being performed on an infant, a
child under 3 years of age, or an uncooperative
adult, sedation can be given to ensure immobiliza-

Scan Studies

531

tion. Children and adults can usually be taught the
importance of remaining very still, and, if claustrophobia is present, an antianxiety agent can be
administered. Diversional interventions, such as
music via earphones, have been used to allay anxiety
in adults.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include the
return of clothing and personal items. Advise the
client to resume food intake and to increase fluid
intake to eliminate the contrast medium, if one was
used.
Adverse reaction to contrast medium: Note and
report nausea, skin rash, sweating, palpitations,
respiratory changes, and changes in vital signs.
Administer ordered antihistamines if needed.
Have resuscitation equipment on hand.
Phlebitis: Note and report redness and swelling at
the IV site. Apply ordered warm compress to site
and elevate arm.

HEAD AND INTRACRANIAL SCANNING
Head and intracranial or brain scanning is a CT
study performed to assist in diagnosing abnormalities of brain tissue and blood circulation and their
effects, such as tumors, infarctions, aneurysms,
infections and inflammations, congenital brain
anomalies, and injury or trauma to the head and
orbital structures. The procedure provides a faster
and safer diagnosis of brain pathology for adults and
children because it eliminates the need for more
invasive studies such as cerebral angiography and
pneumoencephalography. It also provides diagnostic
information that once could be obtained only by
craniotomy. An iodinated contrast medium, possibly
iothalamate meglumine, can be administered IV for
image enhancement when tumor or other pathology
causing the destruction of the blood–brain barrier is
suspected.7 The circulating iodine leaks through the
damaged barrier, the solid portion of the tumor is
visualized, and the size and extent of the mass are
defined.
The CT scanning provides images of internal
structures of the head, brain tissues, and the cerebrospinal fluid (CSF) taken from the top of the head
looking downward. The density and composition
calculations made by the computer are different for
different types of tissue. Differences in tumor from
normal soft tissue, clotted blood from normal blood,
and spaces containing air from those containing CSF
are identified. Detailed images are portrayed on a
screen, photographed, and interpreted for abnormalities in the shape, size, position, symmetry, and

532

SECTION II—Diagnostic

Tests and Procedures

tissue densities of intracranial structures. Other
studies conducted by CT scanning of the head are
for the purpose of detecting abnormalities involving
the eye, ear, and pituitary gland. Various planes are
used in the scanning process for the specific tissues
or organs to be viewed.8
Reference Values
Normal size, shape, and position of intracranial
contents; no tumors, hemorrhage, aneurysm,
infarction, infection, ventricular or tissue
displacement, enlargement, or congenital
abnormalities
INTERFERING FACTORS

Inability of client to maintain the head in an
immobilized position during the procedure
Metal objects such as jewelry, hairpins or hair
clips, dentures, or hearing aid within the examination field
INDICATIONS FOR HEAD AND INTRACRANIAL
SCANNING

Early diagnosis of multiple sclerosis revealed by
detection of sclerotic plaques as small as 3 to 4
mm in diameter
Determination of the cause of increased intracranial pressure
Diagnosis of intracranial benign and malignant
tumors; diagnosis of cyst formation revealed by
changes in tissue densities, such as white with
increased density and darker areas with decreased
density
Determination of the size and location of a
lesion causing a stroke, such as infarct or hemorrhage
Detection of ventricular enlargement or displacement by CSF increases and type of hemorrhage in
infants and children experiencing signs and
symptoms of intracranial trauma or congenital
conditions such as hydrocephalus and arteriovenous (AV) malformations
Differentiation between cerebral infarction and
hemorrhage
Detection of the presence of brain infection or
inflammatory condition such as abscess or necrosis revealed by decreased density
Differentiation among hematoma locations after
trauma, such as subdural, epidural, and cerebral,
and determination of the extent of edema resulting from injury, revealed by higher densities of
blood compared with normal tissue

Evaluation of the effectiveness of treatment and
the course of a disease
Diagnosis of abnormalities of the optic nerve,
detection of a foreign body in the eye, evaluation
of orbital bone fracture or destruction, and
determination of the cause of unilateral exophthalmos9
Diagnosis of abnormalities of the middle ear ossicles and auditory nerve
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
study greatly outweigh the risks to the fetus
Allergy to iodine, if a contrast medium is to be
used
Extreme claustrophobia that prevents the client
from lying still, unless medications are given
before the study
Unstable medical status, that is, vital signs or
dehydration
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any CT scanning study (see section
under “Body Scanning”).
Inform the client that the head is placed in a stabilized holder with the face uncovered and that the
holder is then placed in a frame that revolves
around the head while the pictures are taken.
Inform the client that the study takes 30 minutes
to 1 hour.
Obtain baseline vital signs and neurological
checks for later comparisons.
Obtain a history and assessment of the neurological system, known or suspected neurological
disorders, and results of associated laboratory
tests and other diagnostic procedures.
THE PROCEDURE

The client is placed on a flat table in a supine position with the head on an apparatus that fits into a
frame that revolves around the head in a 180-degree
arc from one side to the other. Imaging is performed
at each degree during this rotation. Additional
images can be taken in other planes as the scanner is
moved to different positions.10 The face is left
exposed during the imaging to allow the client to see
at all times. The client is requested to lie very still
during the procedure because movement causes
blurring of the pictures. An IV administration of an
iodinated contrast medium can be given before the
imaging, or the images can be taken first and then
the medium injected to enhance any unusual findings. The client is advised of the possibility of nausea

CHAPTER 21—Non-Nuclear

and feeling of warmth after the injection and is
instructed to take deep, slow breaths if nausea
occurs. An emesis basin should be made available, if
needed. All images are portrayed on the screen
immediately for viewing and photographs are made
of selected views for future use.
If the study is being performed on an infant, a
child under 3 years of age, or an uncooperative
adult, sedation can be given to ensure immobilization. Most children and adults can be taught and
relied on to lie still during the scanning. An antianxiety agent can be administered if claustrophobia is
present.
NURSING CARE AFTER THE PROCEDURE

NECK AND SPINAL SCANNING
Neck and spinal CT scanning is a study performed to
assist in diagnosing abnormalities of these areas and
resulting consequences, such as structural and
degenerative changes or malformations, tumors,
vascular malformations, and congenital spinal
malformations. The procedure provides detailed
cross-sectional images of selected areas of the cervical, thoracic, or lumbar spine suspected of lesions or
abnormalities. Varying planes are used in the scanning process to produce images of a specific location
or the entire spinal column and its contents.
Reference Values
Normal tissues and structures of the spinal
column and contents; no herniated disks,
tumors, degenerative disease, or stenosis
INTERFERING FACTORS

Inability of client to remain still during the procedure
Metallic objects such as jewelry within the examination field
Barium, feces, or gas in the lower gastrointestinal
(LGI) tract, if lumbar spine is to be imaged
INDICATIONS FOR NECK AND SPINAL SCANNING

Diagnosing benign, primary, and metastatic
tumors of the spine and their location, revealed by
altered density in the areas of pathology as differentiated normal tissue densities

Scan Studies

533

Detecting the presence and location of herniated
disks, usually in the cervical or lumbar spine, with
unilateral or bilateral nerve root compression
Diagnosing or evaluating stenosis of the lumbar
spine with hypertrophy, causing compression of
the cord as the space within the column is
decreased
Detecting cervical spondylosis with cord
compression, caused by structural changes resulting from bone hypertrophy
Diagnosing fluid-filled cysts revealed by increased
density
Detecting vascular malformations in adults and
congenital spinal malformations, that is,
meningocele, myelocele, or myelomeningocele, in
infants11
Monitoring the effectiveness of therapeutic regimen and spinal surgical procedure
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
study greatly outweigh the risks to the fetus
Allergy to iodine, if an iodinated contrast medium
is to be used
Extreme obesity
Extreme claustrophobic response that prevents
the client from remaining still during the procedure, unless medications are given before the
study
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for a head and intracranial CT scanning
study (see section under “Head and Intracranial
Scanning”).
Inform the client about a lumbar puncture if an
air CT is to be performed (see Chapter 8).
THE PROCEDURE

The client is placed in a supine position on a flat
table, which is then placed into the scanner, which
covers the whole body except for the head. The scanner revolves around the client’s body at different
angles, and images are portrayed on the screen.
Selected images are photographed for future viewing. The client is requested to lie very still during the
scanning procedure to prevent blurring of the
pictures. An IV administration of an iodinated
contrast medium can be given before the study or
after the initial imaging to further enhance any
unusual findings and to allow further accentuation
of the spinal vasculature and tissue. The table is
removed from the scanner to administer the contrast
medium to the client; the table is then returned to

534

SECTION II—Diagnostic

Tests and Procedures

the scanner 30 minutes after the client’s IV line has
been established. The client is advised of the possibility of nausea and feeling of warmth after the
injection of the contrast medium and is instructed
to take deep, slow breaths if nausea occurs.
If an air CT is to be performed, a lumbar puncture is made and a small amount of CSF fluid is
replaced with air; the table is returned to the
scanner for client imaging. This procedure provides
enhanced visualization of the area between the
subarachnoid space and surrounding tissue. The IV
injection of an iodinated contrast medium enhances
visualization of very slight differences in tissue
density, providing more accurate diagnostic information. Images are portrayed according to density,
with the bones or vertebrae appearing as white, CSF
as black, and soft tissue as shades of gray.12
As with other CT scans of an infant, child, or
uncooperative adult, sedation can be given before
the procedure to ensure immobilization. An
antianxiety agent can also be given to those clients
who suffer from claustrophobia.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any CT scan study (see section under
“Body Scanning”).
Perform vital signs and neurological checks and
compare with baselines, if indicated.
Maintain the client in a prone or supine position
for 4 to 8 hours, and assess the site for leakage if a
lumbar puncture has been performed.
Lumbar puncture: Note and report changes in
neurological status, increase in blood pressure or
temperature, sensory changes in extremities
(tingling, numbness), irritability, or headache.
Administer analgesic for headache. Perform
neurological checks every 2 to 4 hours for possible
infection or brain or spinal cord damage.

THORACIC SCANNING
Thoracic or chest scanning is a CT study performed
to assist in diagnosing abnormalities of the heart
chambers and great vessels, lungs, and lymph nodes;
examples are masses, aneurysms, lymphoma with
mediastinal lymph node involvement, inflammation
and infection, hiatal hernia, and pleural effusion. A
newer, rapid method of CT scanning called cine scan
can take moving images of the heart.13 The study
provides a cross-sectional view of the chest and its
contents and has the ability to produce a more
detailed display of tissues than do the conventional
x-ray procedures. As different tissues absorb differ-

ent amounts of radiation from the x-rays, density
differences of the tissue type are revealed, based on a
predetermined value that is converted by the
computer into black, white, or gray shades. The
sections of the anatomic area are photographed and
displayed on a screen for viewing.
Reference Values
Normal size, position, and shape of chest organ
tissue and structures; no tumors, cysts, infection
or inflammation, aneurysm, enlarged lymph
nodes, or fluid accumulation
INTERFERING FACTORS

Inability of client to remain still during the procedure
Metal objects such as jewelry within the examination field
INDICATIONS FOR THORACIC SCANNING

Diagnosing pulmonary, esophageal, or mediastinal tumors (primary and metastatic) revealed by
the differences in tissue densities that can go undetected in routine studies because of small size
Diagnosing a benign tumor, such as a granuloma,
and differentiating it from a malignant tumor,
revealed by a sharply defined contour as opposed
to an irregular edge in malignant lesions
Detecting mediastinal and hilar lymphadenopathy in the diagnosis of lymphoma, especially
Hodgkin’s disease
Differentiating tumors or masses from coinsized calcified lesions such as those found in
tuberculosis
Detecting tumor extension of a neck mass to the
thoracic area
Detecting bronchial abnormalities such as stenosis, dilation, or tumor
Detecting aortic aneurysm and differentiating it
from tumors near the aorta
Determining infectious or inflammatory processes such as abscess, nodules, or pneumonitis
Determining fluid, blood, or fat accumulation in
tissues, vessels, or pleuritic space
Evaluating cardiac chambers and pulmonary
vessels
Monitoring or evaluating effectiveness of a
medical or surgical therapeutic regimen
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
study greatly outweigh the risks to the fetus

CHAPTER 21—Non-Nuclear

Allergy to iodine, if an iodinated contrast medium
is to be used
Extreme obesity
Unstable medical status, that is, vital signs or
dehydration
Extreme claustrophobic response that prevents
the client from remaining still during the procedure, unless medications are given before the
study
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any CT scanning study (see section
under “Body Scanning”).
Inform the client that the study takes about 30
minutes to 1 hour.
Obtain a history that includes cardiac and
pulmonary assessment findings, known or
suspected pulmonary conditions, and results of
associated laboratory tests and diagnostic procedures.
THE PROCEDURE

The procedure is the same as for a body CT scanning
study (see “Body Scanning”). The scanner takes
images at different levels and angles of the chest
region, from the neck to the waist instead of
the whole body. Contrast-enhanced studies are
performed by the IV administration of an iodinated
contrast medium for blood vessel evaluation or by
oral administration of a contrast medium for
esophageal evaluation.14
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any CT scan study (see section under
“Body Scanning”).
Monitor vital signs if the client has an acute or
chronic cardiac or pulmonary condition.

ABDOMINAL SCANNING
Abdominal scanning is a CT study performed to
assist in diagnosing abnormalities of the liver,
spleen, pancreas, large and small bowel, biliary
system, kidneys, adrenals, aorta, and lymph
nodes. Identifiable pathology includes tumors,
cysts, inflammation and infection, trauma and
injury, aneurysm, hemorrhage, calculi, duct or
lymph node enlargement, congenital anomalies,
and fluid accumulation in the abdominal cavity.
As in other CT studies, organ contour and contrast differences are displayed by the variations

Scan Studies

535

in densities of soft tissue based on their composition.
Reference Values
Normal size and contour of abdominal structures and organs; no pathology such as masses,
inflammation or infection, duct dilation or
obstruction, bleeding, congenital abnormalities,
or accumulations of fluids or blood in body
organs or cavities

INTERFERING FACTORS

Inability of client to remain still during the procedure
Metal objects such as jewelry and watches within
the examination field
Feces, gas, or barium in the gastrointestinal tract
INDICATIONS FOR ABDOMINAL SCANNING

Diagnosing and locating benign and malignant
tumors and metastasis to other organs, that is,
intrahepatic, pancreatic, gallbladder, kidneys,
spleen, adrenal glands, and small and large bowel
as revealed by changes in tissue density, depending on the organ
Determining pancreatic abnormalities such as
pancreatitis, pseudocysts, bleeding, or abscess
revealed by enlargement, changes in shape, and
decreased tissue density
Detecting dilatation or obstruction, or both, of
the bile or pancreatic ducts with or without calcification or gallstones to differentiate between
obstructive and nonobstructive jaundice
Diagnosing liver abnormalities such as hepatic
abscess, intrahepatic hematomas, cysts, cirrhosis
with ascites, or fatty liver as revealed by an
increased density compared with the surrounding
organs
Diagnosing spleen abnormalities such as tumor,
venous thrombosis, or trauma that results in
hematoma, laceration, or rupture
Evaluating the retroperitoneum for tumors or
infections, revealed by enlarged lymph nodes of
more than 2 cm, or evaluating previously diagnosed lymphadenopathy15
Determining the presence and type of adrenal
tumor, that is, benign adenoma, malignancy, or
pheochromocytoma
Detecting bleeding or hyperplasia of the adrenal
glands
Diagnosing kidney pathology and congenital
anomaly, that is, tumors, cysts, polycystic disease,

536

SECTION II—Diagnostic

Tests and Procedures

calculi and obstructions, horseshoe kidney,
absence of one kidney, or kidney displacement
Determining the spread of a tumor or the invasion of nearby retroperitoneal organs
Detecting infectious or inflammatory conditions
of the bowel and mesentery, that is, appendicitis,
diverticulitis, or Crohn’s disease
Detecting abdominal aortic aneurysm and evaluating the amount of dilation and presence of
intramural thrombi
Defining and locating a lesion site for fine-needle
biopsy and verifying that the needle is in the
proper position
Evaluating the effectiveness of the medical or
surgical regimen
CONTRAINDICATIONS

Contraindications are the same as for thoracic
scanning study (see section under “Thoracic
Scanning”).

NURSING CARE BEFORE THE PROCEDURE
Client teaching and physical preparation are the
same as for any CT scanning study (see section
under “Body Scanning”).
Inform the client that it takes an additional
30 minutes to complete each abdominal and
retroperitoneal study.
Obtain a history that includes gastrointestinal
tract, hepatobiliary, and renal assessment findings; known or suspected conditions; and results
of associated laboratory tests and diagnostic
procedures.
THE PROCEDURE

The procedure is the same as for body CT scanning
(see “Body Scanning”). The scanner is directed at the
abdominal region from the waist to the pelvis
instead of at the whole body. Anatomic image
enhancement can be obtained by the administration
of an oral contrast medium for small- and largebowel imaging and an IV administration of iodinated contrast medium for the other abdominal and
retroperitoneal organs.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any CT scan study (see section under
“Body Scanning”).
Monitor vital signs and intake and output if the
client has a renal disorder.
Impaired renal function: Note and report change
in urinary output or hypertension after iodinated
contrast medium administration. Promote
adequate fluid intake before the study.

PELVIC SCANNING
Pelvic scanning is a CT study performed to assist in
diagnosing abnormalities of the uterus, fallopian
tubes, ovaries, rectum, prostate, urinary bladder, and
lymph nodes. Pathology of these organs that can be
identified are tumors, cysts, infections and inflammations, and hypertrophy. CT of the pelvis is
performed primarily to identify urinary bladder
pathology, because the other pelvic organs can effectively be studied by ultrasonography and other
procedures. The CT scan of the pelvic organs,
however, is used after ultrasonography to determine
the extent of the pathology once it has been identified. The study is based on the same principles of
anatomic identification of organs as the abdominal
CT scan and also includes the use of contrast
enhancement for a more detailed imaging of the
organs (see “Abdominal Scanning”).
Reference Values
Normal size and shape of pelvic organ tissue
and structures; no tumors, cysts, infections, or
lymph node pathology
INTERFERING FACTORS

Inability of client to remain still during the procedure
Metal objects such as jewelry within the examination field
Barium, feces, or gas in the LGI tract
INDICATIONS FOR PELVIC SCANNING

Detecting the extent of tumors, cysts, abscesses, or
other abnormalities of the ovaries, fallopian
tubes, and uterus after a diagnosis has been
obtained by other studies such as ultrasonography
or radiography
Determining prostate hypertrophy or tumors
revealed by enlargement of glandular tissue
Determining the stage of urinary bladder malignant tumor revealed by its invasion through the
bladder wall and extension to pelvic organs and
lymph nodes
Monitoring effectiveness of the medical or surgical regimen
CONTRAINDICATIONS

Contraindications are the same as for thoracic
scan (see section under “Thoracic Scanning”).
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the

CHAPTER 21—Non-Nuclear

Scan Studies

537

same as for any CT scan study (see section under
“Body Scanning”).
Inform the client of the possibility of barium
enema administration before the study.
Inform female clients that a vaginal tampon will
be inserted.
Inform the client that the procedure takes from 30
minutes to 1 hour.
Obtain a history that includes assessment of the
reproductive system of male and female clients,
known and suspected disorders, and results of
associated laboratory tests and diagnostic procedures.

for MRI called gadopentetate dimeglumine
(Magnevist), which can be administered IV to
enhance contrast differences between normal and
abnormal organ tissues.19 MRI is most useful for
tissue density and blood-flow scanning abnormalities for specific organ or disease diagnoses; however,
it is believed that its use will be expanded to include
more diagnostic information about more organs,
sports injuries, and ailments common to the aging
population. At this time, its use is determined by
cost–benefit considerations rather than by risk
considerations.

THE PROCEDURE

BODY MRI

The procedure is the same as for body CT scanning
(see “Body Scanning”). The scanner takes images of
the pelvic region instead of the whole body. In addition to IV administration of an iodinated contrast
medium, a barium contrast medium enema can be
given before the study. A vaginal tampon is inserted
immediately before the study in female clients.16

Body MRI scanning is a study performed to assist in
diagnosing abnormalities in any region of the body
other than the head, that is, chest, abdomen, spinal
cord, pelvis, and extremities. It can reveal tumors
and other soft tissue pathology; bone, joint, and
surrounding tissue disorders; vascular abnormalities
(congenital and noncongenital); and infections. A
special paramagnetic contrast medium can be
administered IV to enhance differences between
normal and abnormal tissues, that is, lesions as
opposed to normal parenchyma.
Scanning provides images based on the water
content of the body, after computer analysis of the
data provided by the scanning apparatus. The
pictures are projected onto a screen, and all or
selected images can be taped for later viewing.
Blood-flow scanning data are computed in milliliters
per minute, pictures are projected onto a screen, and
a printout is made for evaluation. Information for
imaging and blood flow studies is permanently
recorded and stored for future diagnostic reference.

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any CT scan study (see section under
“Body Scanning”).

MAGNETIC RESONANCE
IMAGING
MRI scanning studies are imaging procedures of
body parts. The studies are performed to view characteristics and structures of organs, primarily the
heart, brain, bones and joints, spinal cord, blood
vessels, and soft tissue. MRIs are performed after or
in place of CT scans. Although almost any organ can
be imaged, MRI is used most commonly to evaluate
the nervous and musculoskeletal systems. Of the
MRI procedures performed today, 40 percent are of
the head, 30 percent are of the back, 20 percent are
of the joints, and 10 percent are of the rest of the
body.17 The MRI is performed to determine specific
organ pathology (brain, liver) or to diagnose a
specific condition (multiple sclerosis). Some
consider the procedure overused because it provides
multiple, detailed views without radiation risk.
Different measurements are made in MRI,
depending on the density of soft tissues; the
prolonged relaxation times of certain organs such as
brain, liver, muscle, and spinal cord; the blood flow
and perfusion rates in blood vessels; and the results
of spectroscopy to obtain information about chemical constituents and metabolic changes.18 A new
paramagnetic contrast medium has been developed

Reference Values
Normal anatomic structures and soft tissue
density, biochemical constituents of body
tissues, and flow and perfusion rates; no pathology such as masses, lesions, infarcts, hemorrhage, infections, malformations, or metabolic
abnormalities
INTERFERING FACTORS

Inability of client to remain still during the procedure
Metallic objects within the examination field
that cause artifacts in the image, such as
jewelry; watches; infusion pumps; metallic or
other implants such as heart valves, cochlear or
orthopedic prostheses, rods or screws, or

538

SECTION II—Diagnostic

Tests and Procedures

dentures; hairpins or hair clips; pacemaker; or
ferromagnetic aneurysm clips
INDICATIONS FOR BODY MRI

Diagnosis of renal diseases, that is, hydronephrosis, glomerulonephritis, acute tubular necrosis,
renal vein thrombosis, abscesses, and focal or
diffuse pyelonephritis
Differentiation between renal cysts and lymphocele
Determination of adrenal hemorrhage revealed
by blood characteristics and calcification of the
gland
Acute rejection of kidney transplant
Detection of prostate malignancy and extension
of the tumor with local staging preoperatively
Evaluation of prostate gland for postbiopsy
complications
Evaluation of seminal vesicle abnormalities, such
as hypoplastic, nonsecreting, atrophic, and testicular metabolism
Localization of leiomyomas and other tumors of
the uterus preoperatively
Detection of AV malformations of the vascular
tree and organs such as the spinal cord
Detection and determination of the stage of
malignant tumors of the urinary bladder wall
Diagnosis of benign, primary, and metastatic
tumors in any body organ
Diagnosis of diffuse bone marrow disease such as
leukemia, polycythemia, and bone marrow
changes in Gaucher’s disease
Detection of spinal cord lesions, tumors, and
intramedullary AV abnormalities
Viewing of breast implant for separation, leakage,
and other abnormalities
Detection of abnormalities of the vessels and
blood flow of the extremities, that is, thrombus,
embolism, or atherosclerosis
Determination of blood flow in differentiating
between ischemia and infarction of vessels
Determination of chemical constituent changes
by spectroscopy in the diagnosis of malignancies,
ischemia, and infarction of organs and in the
diagnosis of metabolic disorders
Evaluation of the effects of chemotherapy and
radiation therapy on tumors
CONTRAINDICATIONS

Pregnancy, unless the benefits of performing the
study greatly outweigh the possible risks to the
fetus
Extreme obesity
Unstable medical status, including confusion or
combative demeanor, monitoring of vital signs,

use of cardiopulmonary or other monitoring or
assistive life-support equipment, and use of
neurological or musculoskeletal stimulators
Extreme claustrophobic response that prevents
the client from remaining still while enclosed in
the scanner, unless medications are given before
the study
Presence of cardiac pacemaker that can be deactivated by MRI, metallic clips or prostheses, or
heart valves that can be displaced and cause injury
to the client during MRI
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure requires 30 to 90 minutes,
depending on the region to be examined
That alcohol, caffeine-containing beverages, and
smoking are restricted for at least 2 hours and that
food is withheld for at least 1 hour before the
procedure, especially if blood-flow studies are
being performed
That the usual medication regimen can be continued except for those medications containing iron,
because they will interfere with imaging
That clothing, jewelry, and all metallic objects
including credit cards are removed and that a
hospital gown without snaps or other metallic
closures will be supplied
That a special contrast medium may be given IV
before the study to enhance tissue imaging
That the client is placed into the scanner and that
a steady clanging noise is heard during the procedure; that earplugs are available, if desired, to
block out the noise
That claustrophobia is not uncommon and that
an antianxiety medication can be administered to
allay this feeling; if the client is a child, a sedative
can be given to ensure immobilization during
the study unless blood-flow studies are to be
performed or if the caregiver can talk or read to
the child during the procedure
That there is no discomfort during the procedure
except for a venipuncture if a contrast medium is
administered
Prepare for the procedure:
Ensure that dietary, fluid, and other restrictions
have been followed.
Obtain a history of allergies or sensitivities to
contrast media, last menstrual period to ascertain
possible pregnancy, and known or suspected
pathology.
Inquire about the presence of devices or prostheses in any part of the body, results of laboratory
tests and diagnostic procedures, and presence of
claustrophobia.

CHAPTER 21—Non-Nuclear

Provide a hospital gown and ensure that all metallic objects have been removed from the client and
safely stored with clothing.
Administer ordered medications for anxiety or
sedation, or both, and known sensitivity to iodine
(antihistamine or steroid).
Have client void.
THE PROCEDURE

The client is placed on a narrow, flat table in a supine
position. The table is placed into a cylindrical structure (the scanner) in a special room to ensure that
imaging can be performed without outside interference from radio signals. The client is requested to lie
very still throughout the entire procedure. The face
remains uncovered to allow the client to see out.
Varying radio energy waves are directed at the
area(s) to be imaged. Local surface antennae are
attached to specific areas if improved resolution is
desired.20 If a contrast medium is used for the study,
a specially prepared MRI material is administered IV
before the procedure. The client is advised that he or
she can speak to the technician during the study if
desired. The client is also advised to keep the eyes
closed to promote relaxation and prevent a closed-in
feeling common to those undergoing this procedure.
If nausea is experienced because of claustrophobia,
the client is told to take deep breaths.
If the study is performed on a child, sedation can
be given or the caregiver can read or talk to the child,
because no radiation risk is involved in this procedure. If necessary, judicious use of soft restraints can
be used to immobilize parts of the body.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
returning the client’s clothing and personal items
removed for the study.
Advise the client to resume usual food, fluid, and
medication intake, if applicable.
Phlebitis: Note and report redness and swelling at
the IV site. Apply ordered warm compress to site
and elevate arm.

ANGIOGRAPHY MRI
Angiography MRI scanning is a study performed to
assist in diagnosing abnormalities of the vascular
system. It produces images like those obtained with
conventional angiography without the use of a
contrast medium. It is used to provide quantitative,
functional, and morphologic views of the large and
peripheral blood vessels, as well as blood flow and
characteristics. Areas included in the study are the
vasculature (arteries or veins, or both) of the neck,

Scan Studies

539

thorax, abdomen, extremities, and intracranial
contents. Various methods are used, depending on
the type of information needed to make a diagnosis,
that is, echo-planar flow imaging, real-time imaging,
phase-sensitive flow imaging, time-of-flight flow
imaging, fast imaging, and diffusion and perfusion
imaging.
Reference Values
Normal blood flow, diffusion and perfusion
rate, and blood vessel anatomic structure; no
vascular malformations, aneurysms, thrombosis, vascular stenosis or obstruction, hemorrhage, embolus, or arteriosclerosis
INTERFERING FACTORS

Inability of client to remain still during the procedure
Metal objects within the examination field, such
as jewelry, infusion pumps, metallic or other
implants or prostheses, hairpins or hair clips of
any kind, pacemaker, orthopedic prostheses, rods
or screws, dentures, or heart valve replacement,
which cause artifacts in the image
INDICATIONS FOR ANGIOGRAPHY MRI

Detecting cranial blood vessel and blood-flow
abnormalities, that is, vascular malformations,
aneurysms, thrombosis and occlusion, or hemorrhage
Determining arteriosclerotic plaque and stenosis
of the carotid arteries and evaluating endarterectomy postoperatively
Detecting thoracic aortic aneurysm and diagnosing aortic dissection
Diagnosing pulmonary artery and vein abnormalities such as emboli and anatomic malformations
Detecting coronary occlusion and evaluating
bypass grafts and the angioplasty procedure postoperatively
Determining lower extremity blood vessel and
blood-flow abnormalities, that is, atherosclerosis,
thrombus, embolus, or vascular malformations
Determining abnormal venous blood flow in the
abdomen and pelvis such as that found in thrombosis or occlusion
CONTRAINDICATIONS

Contraindications are the same as for any MRI
scanning study (see section under “Body MRI”).
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the

540

SECTION II—Diagnostic

Tests and Procedures

same as for any MRI scanning study (see section
under “Body MRI”).
Obtain a history that includes known and
suspected vascular disorders and assessment findings related to this system and results of associated laboratory tests and diagnostic procedures,
including surgical interventions.
THE PROCEDURE

The procedure is the same as for any MRI scanning
study except that the scanner is directed at the area
suspected of an abnormality (see “Body MRI”). If an
extremity is to be studied, it is placed on the table
after sites are marked for examination and stored in
the computer. The limb is moved in and out of the
scanner after examination of the ankle, knee, and
hip, with fingertips, wrist, and elbow studies afterward, if all extremities are to be scanned. A blood
vessel or complete extremity can be scanned and
flow data rate obtained in milliliters per minute for
each 100 cm of tissue.21 Measurement of limb
circumference is obtained during the study to reconcile limb size with blood-flow measurement.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any MRI scan study (see section under
“Body MRI”).

ABDOMINAL MRI
Abdominal MRI scanning is a study performed to
assist in diagnosing abnormalities of the abdominal
and pelvic organs. CT is considered to be superior to
MRI in abdominal imaging, except in the assessment
of liver pathology, because it can distinguish organs
from one another. It is performed alone or as part of
a body MRI scan to identify tumor metastasis and
other lesions or soft tissue abnormalities. Contrast
enhancement for liver, spleen, pancreas, stomach,
and proximal duodenum have been developed and
used in MRI imaging of these abdominal organs. As
in other MRI studies, abdominal scans provide
cross-sectional images in the transverse, sagittal, and
coronal planes without any interference from bone
tissue. Images are portrayed on a screen and taped
for viewing and analysis.
Reference Values
Normal anatomic structures, soft tissue density,
and biochemical constituents of body tissues; no
pathology such as masses, lesions, infections, or
inflammations of abdominal organs

INTERFERING FACTORS

Interfering Factors are the same as for any MRI
scanning study (see section under “Body MRI”).
Chest and abdominal movements during respiration will impair clear imaging
INDICATIONS FOR ABDOMINAL MRI

Determining vascular complications of pancreatitis, such as venous thrombosis or pseudoaneurysm
Diagnosing chronic pancreatitis and pancreatic
malignancy, and determining stage of disease
when CT information is insufficient to produce a
satisfactory conclusion
Diagnosing primary or metastatic malignant
tumors of the liver
Detecting liver cysts and cavernous hemangiomas
and differentiating them from malignant tumors
Diagnosing hepatic amebic abscess in combination with CT scanning
Evaluating effectiveness of medical and surgical
interventions and course of a disease
CONTRAINDICATIONS

Contraindications are the same as for any MRI
scan study (see section under “Body MRI”).
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any MRI scanning study (see section
under “Body MRI”).
Inform the client about the use of paramagnetic
contrast media and other medications that
enhance the imaging of specific abdominal organs
by reducing peristalsis.
Obtain a history that includes assessment
findings about the liver, pancreas, and LGI tract
and known or suspected disorders, previous tests,
diagnostic procedures, and medical and surgical
interventions associated with these organs.
THE PROCEDURE

The procedure is the same as for any MRI scan
except that the scanner is directed at the abdominal
organs to be examined (see “Body MRI”). A special
paramagnetic contrast medium such as gadopentetate dimeglumine or a superparamagnetic medium
such as ferrite iron oxide used for spleen, liver, and
pancreas imaging is administered IV before the
procedure. Glucagon can be administered to
improve visualization of the pancreas by removing
artifacts resulting from stomach and bowel peristalsis. Ferric ammonium citrate (Geritol) and
gadopentetate dimeglumine are the media used for

CHAPTER 21—Non-Nuclear

stomach and bowel imaging to decrease the lumen
signal intensity resulting from bowel peristalsis.22
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any MRI scan study (see section under
“Body MRI”).

HEAD AND INTRACRANIAL MRI
Head and intracranial MRI scanning is a study
performed to assist in diagnosing abnormalities
of the brain and face. It can reveal tumors and
other soft tissue lesions, infarctions, aneurysms,
hematomas, nerve demyelination, AV malformations, and other vessel pathology such as atherosclerosis. The study provides cross-sectional images in
multiple planes for viewing as they are projected
onto a screen. Fluid appears as gray and blood
appears dark on the screen. Tissue changes are
revealed by measurements of density and relaxation
time changes.
Reference Values
Normal anatomic structures; soft tissue density;
and blood-flow rate of head, face, nasopharynx,
neck, tongue, and brain; no pathology such
as masses, lesions, infarcts, hemorrhage,
aneurysms, hematomas, edema, or demyelinization of nerve fibers
INTERFERING FACTORS

Interfering factors are the same as for any MRI
scanning study (see section under “Body MRI”).
INDICATIONS FOR HEAD AND INTRACRANIAL
MRI

Diagnosing and locating brain tumors, that is,
primary and metastatic malignancy, acoustic
neuroma, optic nerve tumor, pituitary microadenoma, lipoma, or benign meningioma
Determining vascular disorders of the brain,
that is, aneurysm, infarcts, intraparenchymal
hematoma or hemorrhage, AV malformations
Detecting areas of nerve fiber demyelination in
the definitive diagnosis of multiple sclerosis
Determining the cause of cerebrovascular accident, cerebral infarct, or hemorrhage
Determining cranial bone or face, throat, and
neck soft tissue lesions, such as spread of tumor or
infection
Diagnosing intracranial infections, that is,
pyogenic abscess, ventriculitis, subdural empyema, toxoplasmosis associated with acquired

Scan Studies

541

immunodeficiency syndrome, or tuberculosis,
when procedure is performed in combination
with or in place of CT
Determining the cause of seizures, that is,
intracranial infection or edema or increased
intracranial pressure
Assessing intracranial vascular integrity in evaluating the predisposition to cerebral atherosclerosis
Determining cerebral changes associated with
dementia
Evaluating effectiveness of chemotherapy or radiation therapy in tumor treatment
Evaluating postoperative shunt placement and
function performed for hydrocephalus in infants
CONTRAINDICATIONS

Contraindications are the same as for any MRI
scanning study (see section under “Body MRI”).
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any MRI scan study (see section under
“Body MRI”).
Inform the client about the round-shaped apparatus placed around the head during the scanning
procedure.
Obtain a history that includes the assessment of
the neurological system, known or suspected
neurological disorders, associated laboratory tests
and diagnostic procedures, medical and surgical
interventions, and presence of any ferrous metal
clips or prostheses, implants, or any other interferences to the study.
THE PROCEDURE

The procedure is the same as for any MRI scan study
(see “Body MRI”). The scanner is directed at the
client’s head after the application of a plastic apparatus around the head. This apparatus contains an
antenna to receive the radio waves from the scanning
machine. A special paramagnetic contrast medium,
Gd-DTPA, which has the ability to cross the
blood–brain barrier, can be administered IV to
enhance imaging of the brain tissue.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any MRI scan study (see section under
“Body MRI”).
Monitor vital signs and neurological checks to
ensure stability.

HEART AND CHEST MRI
Heart and chest MRI scanning is a study performed

542

SECTION II—Diagnostic

Tests and Procedures

to assist in diagnosing abnormalities of the cardiovascular and pulmonary structures and circulation.
It involves the evaluation of the anatomy and function of all the areas of the chest, including all
acquired and congenital diseases of the heart and
great vessels except coronary artery disease; that is, it
assists in diagnosing and evaluating thoracic aortic
disease; pericardial disease; cardiac, paracardiac, and
intracardiac masses; and congenital diseases, which
include pulmonary atresia, aortic coarctation, and
single ventricle with transportation of the great
vessels. Although ventricular function and valvular
regurgitation are usually assessed by cardiac nuclear
scan studies (see Chapter 20), cine MRI can also
provide quantitation of ventricular function.23
Two techniques for MRI imaging of the cardiovascular structures are used. One is the electrocardiograph (ECG) gated multislice spin echo sequence
that is used to diagnose heart and aortic anatomic
abnormalities, and the other is the ECG referenced
gradient refocused sequence that is used to diagnose
heart function and analysis of blood-flow patterns.
Because of MRI’s ability to provide accurate quantitative information, it is useful in monitoring
medication and other medical regimens in the treatment of heart failure and hypertension.24
Reference Values
Normal heart structure, soft tissue, and function, including blood-flow rate; no atherosclerosis, coronary infarction, or congenital
anomalies; no thoracic aortic stenosis, occlusion, dissection, or pericardial or pulmonary
effusion
INTERFERING FACTORS

Interfering factors are the same as for any MRI
scanning study (see section under “Body MRI”).
Movement of chest with respirations causes artifacts in the imaging.
INDICATIONS FOR HEART AND CHEST MRI

Diagnosing thoracic aortic diseases, that is, aortic
dissection preoperatively; monitoring after treatment; and diagnosing intramural or periaortic
hematoma
Determining pericardial abnormalities, such as
increased pericardial thickness indicating
constrictive pericarditis or signal pattern indicating hematoma and pericardial effusion
Confirming suspected cardiac and paracardiac
masses, including mediastinal masses after
echocardiography

Identifying congenital heart diseases, that is,
pulmonary atresia, absence or agenesis of a
pulmonary artery, aortic coarctation, and
transportation of the great vessels with a single
ventricle25
Determining cardiac ventricular function by
measurement of right and left volume and wall
thickness, valvular stenosis, or regurgitation by
turbulent blood flow
Diagnosing myocardial infarct and ischemic
conditions of the cardiac muscle
Detecting pleural effusion and fluid within the
lung parenchyma and differentiating this fluid
from hemorrhage fluid
Evaluating bypass grafts and angioplasty postoperatively
CONTRAINDICATIONS

Contraindications are the same as for any MRI
scan study (see section under “Body MRI”).
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any MRI scan study (see section under
“Body MRI”).
Inform the client about the ECG performed
during the study.
Obtain a history that includes assessment of the
heart and great vessels and pulmonary systems,
known or suspected cardiac or lung disorders,
associated laboratory tests and diagnostic procedures, and medical and surgical interventions.
THE PROCEDURE

The procedure is the same as for any MRI scan study,
with the scanner directed at the chest (see “Body
MRI”). If an ECG is to be performed in conjunction
with the scan, the electrodes are applied to the
appropriate sites and the machine is readied to
produce the ECG strips when needed.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any MRI scan study (see section under
“Body MRI”).
Monitor vital signs for stability.

MUSCULOSKELETAL MRI
Musculoskeletal MRI scanning is a study performed
to assist in diagnosing abnormalities of bones and
joints and surrounding soft tissue structures of
cartilage, synovia, ligaments, and tendons. Its multiplanar imaging capability can reveal articular disorders, such as arthritis and temporomandibular joint

CHAPTER 21—Non-Nuclear

detachment; bone marrow disorders, such as
primary tumors, anemias, and avascular necrosis of
bone; and tumors, such as sarcoma, osteochondroma, hemangioma, and metastatic tumors of the
bone, as well as infection and trauma. MRI provides
a more sensitive diagnostic study than CT and x-ray
examination of musculoskeletal conditions. If it is
not performed as an initial procedure, it is
performed when a diagnosis is uncertain or when
the need for surgery must be ascertained.
As with other MRI studies, the scanner, with its
magnetic field and energy specific for the tissue to be
examined, is directed at the area to be examined; it
produces images based on the water content of the
body. The area could be any large joint (usually the
knee, wrist, hip, shoulder, temporomandibular joint,
or spine) or some or all of the bones (usually the
pelvis, long bones, patella, and femoral neck).
Images are projected on a screen after a computer
analysis of the data provided by the scanning.
The images are also taped at the same time for later
viewing.
Reference Values
Normal bones, joints, and surrounding tissue
structures; no articular disease; no bone marrow
disorders; no tumors; no infection; no trauma to
the bones, joints, and muscles
INTERFERING FACTORS

Interfering factors are the same as for any MRI
scanning study (see section under “Body MRI”).
Casted limbs can cause difficulty in placement in
the scanner if the cast is too large.
INDICATIONS FOR MUSCULOSKELETAL MRI

Determining new or recurrent herniated disk of
the spine and differentiating this from spinal
degenerative disease
Diagnosing degenerative spinal diseases such as
spondylosis and arthritis
Determining postoperative changes such as
hematoma, fibrosis, and scar formation in the
diagnosis of spinal stenosis
Determining the cause of low back syndrome
pain, such as disk herniation or lesions
Diagnosing avascular necrosis (osteonecrosis) of
the femoral head or knee
Detecting bone infarcts in the epiphyseal and
diaphyseal sites
Diagnosing bone infections such as osteomyelitis
Evaluating arthritides by identification of
erosions and lesions; synovial inflammation

Scan Studies

543

producing edema; and effusions causing cartilage,
bone, ligament, tendon, and joint capsule destruction26
Evaluating progression or improvement of
synovitis after treatment
Diagnosing primary or secondary malignant
tumor process of the bone marrow, that is,
leukemia or myeloma
Determining bone marrow changes characteristic
of Gaucher’s disease, aplastic anemia, sickle cell
disease, and polycythemia
Detecting tears or degeneration of ligaments,
tendons, and meniscus resulting from trauma or
pathology
Differentiating between stress fractures and
neoplasms of the bone
Evaluating meniscal detachment of the temporomandibular joint and functional derangement of
the masticatory muscles, such as fibrosis and
contracture, or osseous abnormalities such as
fusion or sclerosis27
Diagnosing benign and malignant tumors and
cysts of bones and soft tissues, that is, osteogenic
sarcoma, fibrosarcoma, osteochondroma, muscular and osseous hemangioma, liposarcoma,
aneurysmal cysts, and other cysts
CONTRAINDICATIONS

Contraindications are the same as for any MRI
scan study (see section under “Body MRI”).
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any MRI scan study (see section under
“Body MRI”).
Obtain a history that includes musculoskeletal
system assessment findings, known or suspected
musculoskeletal disorders, associated laboratory
tests, diagnostic procedures, and medical and
surgical interventions.
THE PROCEDURE

The procedure is the same as for any MRI scan study
(see “Body MRI”). The scanner is directed at the
body area to be examined, which determines the
planes of imaging and the size and configuration of
surface coils used to transmit or receive the magnetic
radiation. A paramagnetic medium can be used as a
contrast enhancement to define the vascularity of a
lesion and its boundary with adjacent muscle.28
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any MRI scan study (see section under
“Body MRI”).

544

SECTION II—Diagnostic

Tests and Procedures

Bone and soft tissue pain: Note and report pain
severity. Administer ordered analgesic as needed
for comfort before or after the procedure.
REFERENCES
1. Corbett, JV: Laboratory Tests and Diagnostic Procedures with
Nursing Diagnoses, ed 3. Appleton & Lange, Norwalk, Conn, 1992,
p 541.
2. Berkow, R: The Merck Manual, ed 16. Merck Sharp and Dohme
Research Laboratory, Rahway, NJ, 1992, p 2005.
3. Fischbach, FT: A Manual of Laboratory Diagnostic Tests, ed 4. JB
Lippincott, Philadelphia, 1992, p 676.
4. Corbett, op cit, p 544.
5. Fischbach, op cit, p 916.
6. Ibid, pp 676–677.
7. Pagana, KD, and Pagana, TJ: Mosby’s Diagnostic and Laboratory
Test Reference. Mosby–Year Book, St Louis, 1992, p 220.
8. Fischbach, op cit, pp 672–673.
9. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 575.

10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.

Pagana and Pagana, op cit, p 222.
Nurse’s Reference Library, op cit, p 761.
Ibid, pp 760–761.
Corbett, op cit, p 541.
Pagana and Pagana, op cit, p 223.
Ibid, p 213.
Fischbach, op cit, p 677.
Margulis, AR, and Gooding, CA (eds): Diagnostic Radiology 1989.
JB Lippincott, Philadelphia, 1989, p 27.
Ibid, p 105.
Ibid, p. 35.
Fischbach, op cit, p 918.
Ibid, p 918.
Margulis, op cit, p 35.
Ibid, p 228.
Ibid, pp 227, 229.
Ibid, p 228.
Ibid, p 228.
Ibid, p 383.
Ibid, pp 413, 418.

CHAPTER

Manometric Studies
TESTS COVERED
Cystometry, 546
Uroflowmetry, 548
Urethral Pressure Profile, 549
Esophageal Manometry, 550
Arterial Plethysmography, 552

Venous Plethysmography, 553
Body Plethysmography, 553
Oculoplethysmography, 554
Contraction Stress Test, 556

INTRODUCTION

Manometry is the measurement of liquid or gas pressures expressed in
millimeters of mercury (mm Hg), or torr, or in centimeters of water (cm H2O).1 The types of
liquids measured are blood in the arteries and veins, spinal fluid in the spinal column, and
stomach contents in the esophagus. The type of gas measured is the lung air volume. Special
devices are used for measurement, depending on the organ to be examined and the liquid or
gas to be measured: a calibrated tube for spinal fluid pressure; a transducer for blood volume
changes; a transducer attached to gastric tubes for sphincter competency; a cystometer attached
to a urinary catheter for bladder capacity and pressure and urethra competency; or a transducer
attached to a mouthpiece for lung gas volume, resistance, and compliance.
Plethysmography is a technique that uses different types of transducers, such as air, water,
impedance, and photoelectric transducers, to determine and record volume and pressure
changes of a body organ or extremity.2
A signed informed consent form is required for manometric procedures and for oculoplethysmography, which are considered invasive. No consent form is required for other types of
plethysmography. The examinations are performed alone or in association with other diagnostic procedures by physicians or technicians in specially equipped rooms.

URODYNAMIC STUDIES
Urodynamic studies involve the measurement of
urinary bladder function. They include neuromuscular function (cystometry), urinary flow rate
(uroflowmetry), and urethral pressure and closing
ability (urethral pressure profile). Among the
aspects of bladder function studied are the changes
in bladder, urethral, and intra-abdominal pressures;
the characteristics of the urinary flow; and the external sphincter and pelvic floor muscle competency.

The studies are usually performed to determine the
cause of abnormal voiding patterns, bladder pathology, and the effect of therapeutic regimens on bladder function. One or more of the studies can be
performed in conjunction with other urologic
procedures, such as excretory urography and
cystourethrography (regular and voiding). The most
common complication resulting from these studies
is urinary bladder infection.
Physiologically, micturition is facilitated or inhibited by neurological centers. Motor function of the
545

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Tests and Procedures

TABLE 22–1
Type/Site of Damage

Types and Effects of Neurogenic Bladder
Characteristics

Causes

Detrusor muscle hyperreflexia (above the level
of voiding reflex)

Uninhibited or mild spastic
incomplete/reflex spastic
complete neurogenic bladder

Parkinson’s disease, cerebrovascular
accident, (CVA), spinal cord injury,
(SCI), aging process

Detrusor muscle areflexia
(level of sacral voiding
reflex)

Autonomous or flaccid, nonreflexive, incomplete/sensory
paralytic or motor paralytic
neurogenic bladder

Diabetes mellitus, spinal cord tumor,
SCI, congenital spinal cord defects,
multiple sclerosis

External sphincter muscle

Impaired relaxation

Local irritation or inflammation, anxiety
or depression

Brainstem

Loss of perception and control
of bladder

Brain tumor, brain injury

detrusor muscle and the internal sphincter is
controlled by the parasympathetic nervous system
with cell bodies located in the lower spinal cord (S2
to S4). The cell bodies communicate with the bladder through the pelvic nerve. In the brain, detrusor
muscle activity and external sphincter activity are
controlled by the center in the brainstem, and the
conscious control of micturition is controlled by the
center in the brain cortex. Abnormalities of bladder
function and structure can result from an interruption at any level of sensory or motor innervation or
both. Other abnormalities can result from diseases
(neuropathies from diabetes or multiple sclerosis)
involving the neurons that supply the bladder and
interrupt sensory or motor pathways or both.3
Trauma and injury to the spinal cord or spinal roots,
cerebral and cerebrovascular disorders, radical
pelvic surgery, neuropathies, and advanced age are
known causes of neurogenic bladder manifestations.

CYSTOMETRY
Cystometry is a manometric study performed to
assist in diagnosing motor and sensory abnormalities (neurogenic bladder), obstructive abnormalities

(prostatic hypertrophy, urethral stenosis), or infectious disorders (recurrent cystitis) that affect urinary
bladder structure and function. The study measures
bladder pressure during the filling and emptying
phases in cm H2O and provides information about
uninhibited bladder contractions, sensations of
bladder fullness and need to void, and ability to
inhibit voiding. These abnormalities cause incontinence and other signs and symptoms associated
with impaired patterns of micturition. Neuromuscular function of the bladder is determined by
measurement of detrusor muscle competency,
intravesical pressure and capacity, and response to
thermal stimulation.4
The types and effects of neurogenic bladder
dysfunction can be diagnosed with this study (Table
22–1). In addition to lesions and trauma of the
spinal cord, the effects of other neurological disorders such as neuropathies, congenital anomalies,
neurectomy, tumors, and cerebrovascular conditions
on urinary patterns and vesical function can be evaluated. Cystometry can be performed in association
with cystoscopy (see Chapter 16) and sphincter electromyography (see Chapter 23).

Reference Values
Normal sensory perception of bladder fullness, desire to void, ability to inhibit
urination, and response to temperature (hot and cold)
Normal bladder capacity: 350 to 750 mL for men and 250 to 550 mL for women
Normal functioning bladder pressure: 8 to 15 cm H2O
Normal sensation of fullness: 40 to 100 cm H2O
Normal bladder pressure during voiding: 30 to 40 cm H2O
Normal detrusor pressure: less than 10 cm H2O
Urethral pressure that is higher than bladder pressure to ensure continence

CHAPTER 22—Manometric

INTERFERING FACTORS

Inability of client to understand and carry out
instructions during the procedure
Inability of client to void in a supine position;
straining at voiding during the study
High level of client anxiety or embarrassment
Administration of drugs such as muscle relaxants
or antihistamines that affect bladder function
INDICATIONS FOR CYSTOMETRY

Determining the cause of bladder dysfunction
and pathology: neurological, obstructive, or infectious disorders, for example
Evaluating signs and symptoms of urinary elimination pattern dysfunction: dysuria, frequency,
hesitancy, nocturia, urgency, retention, and
incontinence
Diagnosing the type of incontinence: functional
(involuntary and unpredictable), reflex (involuntary when a specific volume is reached), stress
(weak pelvic muscles), total (continuous and
unpredictable), urge (involuntary when urgency
is sensed), or psychological (dementia, confusion
affecting awareness)
Determining type of neurogenic bladder and
effect on urination and determining bladder
function and structure based on cause and level of
abnormality or innervation interruption
Evaluating the usefulness of drug therapy on the
detrusor muscle and internal and external sphincters in controlling urinary bladder function
Determining cause of urinary retention: urethral
obstruction, prostatic hypertrophy, meatal stenosis, sexually transmitted infections that produce
strictures, and so on
Detecting urinary abnormalities resulting from
congenital defects such as spina bifida,
myelomeningocele, or vesicoureteral reflux
Determining the cause of recurrent urinary tract
infections (UTIs)
Evaluating the management of neurological bladder before surgical interventions: sphincterectomy or reconstruction of the sphincter, urinary
diversion, nerve resection, or transurethral
prostatectomy
CONTRAINDICATIONS

Acute UTI: Study can cause infection to spread to
kidneys.
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure requires 30 to 45 minutes
unless further studies are to be made

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547

Nursing Alert

The procedure should be performed using
strict sterile technique to prevent infection.
Clients with spinal cord injury (SCI) should
be transported on a stretcher, and the study
should be performed without transferring the
client from the stretcher.
That there are no food or fluid restrictions
That all clothing or clothing from the waist down
is removed and a hospital gown worn
That the client will be draped appropriately and
privacy protected
That the client will be requested to refrain from
straining at urination and to stand or walk during
the study
That a catheter is inserted into the bladder and
solutions or gas are instilled while urethral and
bladder pressures are measured
That the client should report pain, sweating,
nausea, headache, and urge to void experienced
during the study
That the only discomfort is the insertion of the
urethral catheter
Prepare for the procedure:
Obtain a history of signs and symptoms of
impaired urinary function, known or suspected
disorders leading to urinary dysfunction, associated diagnostic tests and procedures, medications,
and medical and surgical interventions.
Have client void.
THE PROCEDURE

The client is placed on the examination table in a
supine or lithotomy position or remains on a
stretcher in a supine position if SCI is present.
Privacy is ensured and embarrassment prevented
with proper draping while in position. The client is
requested to void and lie still during the procedure.
During the voiding, characteristics are assessed such
as the time started, force and continuity of the
stream, volume voided, and presence of dribbling,
straining, or hesitancy.5 A catheter is inserted into
the bladder using sterile technique and the residual
urine is measured and recorded. A test for sensory
response to temperature is then performed: 30 mL
of room temperature sterile water and then 30 mL of
warm sterile water are instilled into the bladder, and
the client’s sensations are assessed and recorded. The
fluid is removed from the bladder and the catheter is
connected to a cystometer, which measures the pressures. Sterile normal saline, distilled water, or carbon
dioxide gas in controlled amounts are instilled into

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Tests and Procedures

Reference Values
Normal Urinary Flow Rate by Age and Gender
Male

Female

Child

100 mL/10–12 sec

100 mL/10–15 sec

Adult

200 mL/12–21 sec

200 mL/15–18 sec

Older adult

200 mL/9 sec

200 mL/10 sec

Note: No external sphincter dysfunction, obstruction, or hypotonia of the detrusor muscle.

the bladder. When the client indicates the urge to
void, the bladder is considered full and amounts and
times are recorded. Pressure and volume readings
are also recorded and graphed for response to heat,
fullness of bladder, urge to void, and ability to
inhibit voiding. The client is requested to void without straining, and pressures are taken and recorded
during this activity. After completion of voiding, the
bladder is emptied of any other fluid and the
catheter is withdrawn unless further testing is
planned.
If further testing is performed to determine
whether abnormal bladder function is caused by
muscle incompetency or interrupted innervation, an
anticholinergic such as atropine or cholinergic
medication such as bethanechol (Urecholine) can be
injected and the study repeated in 20 or 30 minutes.6
NURSING CARE AFTER THE PROCEDURE

Advise the client to increase fluid intake and
report any changes in voiding pattern or urine
characteristics such as hematuria, cloudy and
foul-smelling urine, inability to void or incontinence, dysuria, frequency, and urgency.
Provide a warm tub bath to relieve discomfort at
the urethral site.
If indicated, monitor intake and output (I&O) for
24 to 48 hours.
Urinary bladder infection: Note and report positive urine culture, burning, frequency, or urgency.
Monitor culture results. Administer ordered
antimicrobial as ordered. Offer sitz bath for
comfort.
Autonomic reflexia: Note and report sweating,
flushing, bradycardia, hypertension, and severe
headache. Administer propantheline bromide
(Pro-Banthine) as ordered.
Sepsis: Note and report temperature elevation,
chills, or hematuria after third voiding. Monitor
temperature and vital signs. Administer ordered
antimicrobial and antipyretic drugs.

UROFLOWMETRY
Uroflowmetry is a manometric study performed to
measure the urinary flow rate during the process of
urination over a period of time. It is performed to
assist in diagnosing abnormalities of the urinary
pattern. It includes the recording and plotting of
urinary volume flow over a period of time to determine the presence of external sphincter dysfunction,
obstruction, and detrusor muscle hypotonia, any of
which can lead to incontinence or urinary bladder
infection. The study uses a system that includes a
device called a uroflowmeter, a container to hold the
urine, a transducer, start and flow cables, and a
recorder. Evaluation of the test results is based on the
volume of urine in milliliters, with output measured
in milliliters per second or per minute, and on
the client’s age and gender.7 This test has generally
been replaced by the urethral pressure profile unless
the insertion of a urinary bladder catheter is
contraindicated.
INTERFERING FACTORS

Inability of client to remain still and carry out
instructions during the study
Toilet tissue or other material that alters study
findings
Administration of drugs such as anticholinergics
or muscle relaxants that affect bladder and
sphincter function
Room temperature changes that can affect transducer measurements
INDICATIONS FOR UROFLOWMETRY

Determining abnormal urinary flow patterns in
the evaluation of incontinence and recurrent
urinary bladder infections
Diagnosing external sphincter dysfunction
revealed by an increased flow rate
Determining the cause of abnormal urinary flow
patterns (detrusor muscle hypotonia, outflow
obstruction) revealed by a decrease in flow rate

CHAPTER 22—Manometric

NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any urodynamic study (see section under
“Cystometry”), except that a catheter is not inserted
for this procedure.
Inform the client that the study is completed in
about 15 minutes, that it is performed while
seated on a commode (women) or in a standing
position (men), and that the pressures are measured during the process of voiding.

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any urodynamic study (see section under
“Cystometry”).

549

Urethral pressures are evaluated by the client’s age
and gender and are measured in cm H2O.
INTERFERING FACTORS

Interfering factors are the same as for any urodynamic study (see section under “Cystometry”).
INDICATIONS FOR URETHRAL PRESSURE
PROFILE

Determining external urethral sphincter competency in the presence of incontinence or abnormal
urinary elimination pattern
Detecting cause of stress incontinence in women,
resulting from weakened pelvic floor muscle
Determining obstruction of urinary flow caused
by hypertrophic prostate gland and evaluating
incontinence after prostatectomy
Evaluating drug therapy regimen for urethral
sphincter muscle control
Evaluating function and management of postoperative procedures after sphincterectomy or artificial urethral device implantation

THE PROCEDURE

The client is placed in a sitting position on a
commode (women) or in a standing position next to
the commode (men). Privacy is ensured by draping
or covering the client from the waist down. A
weight-recording device (gravimetric uroflowmeter)
is placed at the bottom of the commode. This unit
weighs the urine as it flows, and weight changes are
recorded electronically by converting weight to
milliliters and recording time frames in seconds or
minutes. The client is requested to void without
straining during the procedure. Volume and times
are recorded on a graph from the beginning of voiding to the end. The characteristics of the peaks of the
curve on the graph indicate incontinence (high peak
flow), detrusor muscle abnormality (many peaks),
or obstruction (low peak flow).8

Studies

CONTRAINDICATIONS

Acute UTI: Study can cause infection to spread to
the upper urinary tract and kidneys.
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any urodynamic study (see section under
“Cystometry”).
Inform the client that it takes 15 minutes to
complete the study and that it has no adverse
effects.

URETHRAL PRESSURE PROFILE

THE PROCEDURE

Urethral pressure profile is a manometric study
performed to measure pressure changes along the
urethra while the bladder is at rest. It is performed to
assist in the diagnosis of urethral sphincter function
abnormalities and to evaluate the effectiveness of
surgical correction of sphincter abnormalities.

The client is placed on the examination table in a
supine or a lithotomy position. The client is draped
for privacy and prevention of embarrassment and is
requested to remain very still during the procedure.
A double-lumen catheter connected to a transducer
is inserted into the bladder, and fluid or gas is

Reference Values
Normal Urethral Pressures for Age and Gender
Male

Female

Young adult

37–126 cm H2O

55–103 cm H2O

Middle adult

35–123 cm H2O

31–115 cm H2O

Older adult

35–105 cm H2O

35–75 cm H2O

Note: No obstruction or incontinence.

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SECTION II—Diagnostic

Tests and Procedures

constantly infused by a pumping apparatus. Urethral
pressures are measured along the urethra while the
catheter is withdrawn. When the study is completed,
the catheter is removed. Pressure readings are
recorded and analyzed for abnormalities based on
the age and gender of the client.

hypotension) can result in inflammation and cause
associated pyrosis and pain. In time, inflammation
results in edema and erosion of the esophageal
lumina, forming thickness and scar tissue and causing associated dysphagia.10

ESOPHAGEAL MANOMETRY

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any urodynamic study (see section under
“Cystometry”).

ESOPHAGEAL STUDIES
Esophageal studies involve the measurement of
esophageal sphincter pressure, peristalsis and
contraction, and acidity through the use of
esophageal manometry, esophageal acid reflux and
clearing, and acid perfusion (Bernstein) tests.
Manometry is usually performed to detect the cause
of pyrosis and dysphagia by determining esophageal
sphincter competency and the effectiveness and
coordination of esophageal movements during swallowing. The acid reflux test measures backflow or
reflux of acid from the stomach into the esophagus,
the acid clearing test measures motility in the esophagus, and the acid perfusion test confirms and evaluates esophageal reflux.9 One or more of the tests
can be performed, depending on the client’s symptoms, and a definitive diagnosis can be obtained by
radiologic (barium swallow) or endoscopic (esophagogastroduodenoscopy [EGD]) studies.
The esophagus is a tubelike organ that receives
food from the pharynx and moves it into the stomach by peristaltic contractions. The upper and lower
parts of the esophagus act as sphincters to control
passage of the food from the pharynx into the stomach. Failure of the lower sphincter to relax (sphincter hypertension) can cause achalasia as food passage
into the stomach is slowed. This condition can result
in aspiration of esophageal contents into the lungs.
Reflux of stomach contents containing gastric acid
into the esophagus at the lower sphincter (sphincter

Esophageal manometry and associated tests are
manometric studies performed to assist in evaluating esophageal muscle function and diagnosing
structure abnormalities. The studies measure
esophageal pressure and the presence or effects of
gastric acid in the esophagus. Abnormalities cause
dysphagia, regurgitation, and pyrosis, indicating
possible spasms, achalasia, chalasia in children,
gastroesophageal reflux, esophagitis, and esophageal
scleroderma.
Esophageal manometry measures lower
esophageal sphincter pressure and motility patterns
that result during swallowing. The acid reflux test
measures the presence of gastric acid in the lower
esophagus. The acid clearing test measures the
motility by the number of swallows it takes to clear
hydrochloric acid from the esophagus. The acid
perfusion test measures or evaluates the effect of
hydrochloric acid on the esophagus to confirm that
symptoms of pain are caused by esophagitis and not
some other condition that can cause chest or epigastric pain.
INTERFERING FACTORS

Inability of client to understand or follow instructions during the study
Intake of food or fluids within 6 hours before the
study
Administration of medications such as sedatives,
antacids, anticholinergics, cholinergics, or corticosteroids, which can change pH or relax the
sphincter muscle
INDICATIONS FOR ESOPHAGEAL MANOMETRY

Diagnosis of pyrosis and dysphagia to determine

Reference Values
Normal Esophageal Structure and Function
Esophageal sphincter pressure

10–20 mm Hg

Esophageal secretions

pH 5.0–6.0

Acid reflux

No regurgitation into the esophagus

Acid clearing

10 swallows or less

Acid perfusion

No gastroesophageal reflux

Note: No gastroesophageal reflux, esophagitis, achalasia, spasms, or chalasia.

CHAPTER 22—Manometric

whether the cause is gastroesophageal reflux or
esophagitis
Diagnosis of chronic gastroesophageal reflux
revealed by low pressures in manometry, decrease
in pH in acidity test, and pain during acid reflux
and acid perfusion tests
Diagnosis of esophagitis revealed by decreased
motility requiring more than 10 swallows to clear
acid from the esophagus in the acid clearing test
Diagnosis of achalasia revealed by failure of the
lower sphincter to relax when swallowing and by
spasms, causing increased pressure in manometry
Diagnosis of chalasia in children, revealed by
relaxed esophageal sphincter causing low pressures in manometry
Suspected esophageal scleroderma revealed by
impaired sphincter and abnormal contractions
causing low pressures in manometry
Differentiation between cardiac condition and
epigastric pain resulting from esophagitis as
revealed by introduction of acid in the acid perfusion test
CONTRAINDICATIONS

Unstable medical condition: vital signs,
esophageal varices or bleeding, infection, cardiac
condition
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are as
follows:
Foods and fluids are withheld for 6 to 8 hours and
medications for 24 hours before the study.
For the client with diabetes, make special arrangements for insulin administration, meals, and time
for the study to be performed.
Inform the client that one or more tubes are
inserted into the mouth or nose and positioned
into the esophagus and that some gagging and
discomfort are experienced during insertion and
placement.
Take baseline vital signs for later comparisons.
Obtain a history that includes signs and symptoms of gastrointestinal distress, known or
suspected gastrointestinal disorders or hiatal
hernia, treatments, and medication regimens.
THE PROCEDURE

The client is placed in a high-Fowler’s or a sitting
position initially while the tubes are inserted. After
placement of the tube, the client is placed on the
examination table in a supine position.
Esophageal Manometry. One or more small tubes
are inserted into the esophagus via the mouth. A
small transducer is attached to the ends of the tubes

Studies

551

to measure the lower esophageal sphincter and
intraluminal pressures and the regularity and duration of peristaltic contractions to determine motility
abnormalities. The tubes are allowed to pass into the
stomach and then pulled backward into the lower
esophagus. Pressures are taken and recorded. The
client is requested to swallow, and the motility
pattern is recorded on a graph. Lower esophageal
sphincter pressure of 0 to 5 mm Hg is considered
incompetent and indicative of gastroesophageal
reflux. A pressure of 50 mm Hg is indicative of achalasia. This test can also be performed during
esophagoscopy via the endoscope to measure lower
esophageal sphincter pressure.
Esophageal Acid and Clearing. With the tubes in
place in the esophagus, a pH electrode probe is
inserted into the esophagus. The client can be
requested to lift both legs or perform Valsalva’s
maneuver to stimulate reflux of stomach contents
into the esophagus. If acid reflux is absent, 100 mL of
0.1 percent hydrochloric acid (HCl) is instilled into
the stomach over a period of 3 minutes and the pH
measurement repeated. If reflux is present, the pH
probe indicates a drop to between 1.0 and 3.0 as the
acid is regurgitated into the esophagus. To determine
acid clearing, HCl is instilled into the esophagus and
the client is requested to swallow while the probe
measures pH. The number of swallows it takes to
clear the acid from the esophagus based on the pH
probe readings determines the esophageal motility
capabilities in clearing the acid from the esophagus.
Acid Perfusion. A catheter is inserted through the
nose into the esophagus. The client is requested to
inform the technician when pain is experienced.
Normal saline solution is allowed to drip into the
catheter at about 10 mL per minute. Then HCl is
allowed to drip into the catheter. Pain experienced
when HCl is instilled determines the presence of an
esophageal abnormality. If no pain is experienced,
the client’s symptoms are the result of some other
condition.
NURSING CARE AFTER THE PROCEDURE

Inform the client that some irritation of the nose
and throat is common for 24 hours after the study
and that discomfort can be reduced by gargling
with warm water.
Monitor vital signs, compare with baseline readings, and monitor bleeding from the nose or
mouth.
Resume food, fluid, and medications after the
study.
Aspiration of contents into lungs: Note and
report any change in respirations (dyspnea,
tachypnea, adventitious sounds). Suction mouth,

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SECTION II—Diagnostic

Tests and Procedures

pharynx, and trachea. Administer ordered oxygen.
Have resuscitation equipment on hand.

PLETHYSMOGRAPHY
Plethysmography is a noninvasive diagnostic technique used to measure changes in the size of blood
vessels by determining changes in the volume of
blood in the vessels of the eye, extremities, or neck or
changes in gas volume in the lungs. Various transducers and instruments are used to determine arterial, venous, or lung abnormalities: body box,
impedance plethysmograph, pulse volume recorder,
and others. Plethysmography is usually performed
instead of or after Doppler examination in vascular
studies and in conjunction with pulmonary function testing in lung studies. There are no complications associated with plethysmography.

Determination of changes in toe or finger pressures when ankle pressures are elevated, as a result
of calcifications in arteries
Determination of the effect of trauma on the
arteries in an extremity
Determination of peripheral small artery changes
(ischemia) caused by diabetes and differentiation
of these changes from other neuropathy
Diagnosis of vascular changes associated with
Raynaud’s phenomenon
Determination of degree and location of arterial
atherosclerotic obstruction and vessel patency in
peripheral atherosclerotic disease
Determination of inflammatory changes causing
obliteration in the vessels in thromboangiitis
obliterans
Confirmation of suspected acute arterial
embolization
CONTRAINDICATIONS

ARTERIAL PLETHYSMOGRAPHY
Arterial plethysmography is a manometric study
that measures toe or finger volume changes after
Doppler ultrasonography when ankle, thigh, and
arm pressures are elevated. Normal toe pressure
should equal or exceed ankle pressure, and normal
finger pressure should equal or exceed wrist pressure.11 This assessment of arterial circulation in the
upper or lower limbs can assist in the diagnosis of
lower extremity occlusive diseases and upper
extremity arteriosclerotic disease. The study requires
very little cooperation from the client and can be
performed at the bedside for those who cannot be
moved to the vascular laboratory.
INTERFERING FACTORS

Smoking 2 hours before the study constricts the
arteries.
Environmental temperatures (hot or cold) can
affect peripheral circulation.
Arterial occlusion proximal to the extremity to be
examined can prevent blood flow to the limb.
INDICATIONS FOR ARTERIAL PLETHYSMOGRAPHY

Suspected arterial occlusive disease revealed by a
decreased pulse wave amplitude and a pressure
difference of greater than 20 mm Hg

An extremity that is cold to the touch, cyanotic, or
pale in color, indicating a compromised blood
flow to the limb
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure requires about 30 minutes
That foods and fluids are allowed but that smoking is restricted for at least 2 hours before the
study
That all clothing is removed from the extremities
that are to be examined
That some cuffs are applied to the extremity to
measure the blood flow
That no pain is associated with the study
Prepare for the procedure:
Obtain a history of signs and symptoms of vascular disorders, known or suspected peripheral
vascular disease, associated diagnostic tests and
procedures, and medication regimen.
Ensure that the client has refrained from smoking
for 2 hours before the study.
Obtain baseline vital signs for later comparison.
Administer an ordered analgesic to control pain, if
pain is present.
Have client void.

Reference Values
Normal arterial pulse wave:

Steep upslope and less steep downslope, with narrow, pointed peaks

Normal pressure:

20 mm Hg in the systolic difference between the lower and upper
extremities; toe pressure 80% or more of ankle pressure; finger pressure
80% or more of wrist pressure12

CHAPTER 22—Manometric

THE PROCEDURE

The client is placed on the examination table or in a
bed in a semi-Fowler’s position. The client is
requested to lie very still during the procedure.
Three cuffs are applied to the extremity and attached
to a pulse volume recorder, which displays the
amplitude of each pulse wave on a paper called the
plethysmogram. The cuffs are inflated to 65 mm Hg,
and the pulse waves of each cuff are measured. These
measurements, when compared with a normal limb,
determine the presence of arterial occlusive
disease.13
NURSING CARE AFTER THE PROCEDURE

Help the client dress, if help is needed.
Handle the extremity gently if severe ischemia,
ulcers, and pain are present.

VENOUS PLETHYSMOGRAPHY
Venous plethysmography is a manometric study that
measures changes in venous capacity and outflow
(volume and rate of outflow). It is usually performed
to assist in the diagnosis of a thrombotic condition
that causes obstruction of the major veins of the
extremities. The study is performed on the leg and
uses two blood pressure cuffs, one occluding circulation and one containing a plethysmography
recorder. The study can be performed in conjunction with Doppler ultrasonography. Suspected deep
venous thrombosis (DVT) that is not confirmed by
plethysmography can require venography studies.
The study can be performed at the bedside for those
clients who cannot be transported to the vascular
laboratory.

Studies

553

obstruction revealed by an absence of an increase
in leg volume as venous outflow is obstructed
Determining valve competency in conjunction
with Doppler ultrasonography in the diagnosis of
varicose veins
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any vascular plethysmography study (see
section under “Arterial Plethysmography”).
THE PROCEDURE

The client is placed on the examination table or in a
bed in a semi-Fowler’s position. Two cuffs are
applied to the extremity, with one cuff attached to a
pulse volume recorder. One cuff is placed on the
proximal part of the extremity (occlusion cuff), and
the second cuff is placed on the distal part of the
extremity (recorder cuff). The recorder cuff is
inflated at the level of 10 mm Hg, and the effects of
respiration on the volume in the veins are evaluated.
Absence of changes during respirations indicates the
presence of venous occlusion. Next, the occlusion
cuff is inflated to the level of 50 mm Hg to record the
venous volume on the pulse monitor. The occlusion
cuff is deflated after the highest volume is recorded
in the recorder cuff. A delay in the return to preocclusion volume indicates venous thrombotic occlusion.14
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any vascular plethysmography study (see
section under “Arterial Plethysmography”).

BODY PLETHYSMOGRAPHY
Reference Values
Normal venous blood flow in extremities; no
incompetent valves, thrombosis, or thrombotic
obstruction in the major veins of the extremities; venous filling time should be greater than
20 seconds.
INTERFERING FACTORS

Cold air or cold extremity, constricting the vessels
High level of anxiety, causing a tenseness of
muscles
Venous occlusion at the proximal part of the
extremity to be examined, affecting blood flow to
the extremity
INDICATIONS FOR VENOUS PLETHYSMOGRAPHY

Diagnosing partial or total venous thrombotic

Body plethysmography is a manometric study that
measures the total amount of air within the thorax
(volume), both in and out of ventilatory communication with the lung; the elasticity (compliance) of
the lungs; and the resistance to air flow in the respiratory tree. Values are based on the height, weight,
and gender of the client. The volume is calculated in
milliliters by multiplying the pressure by the volume
obtained during the test. Compliance is calculated in
liters per centimeter of H2O by dividing the volume
change by the pressure change. Airway resistance is
calculated in centimeters of H2O per liter per second
by dividing the pressure change by the flow change.
The diagnosis of pulmonary disease is determined
from increases in volume, compliance, and resistance, indicating obstructive lung disorders, and
from decreases in compliance, indicating restrictive
lung disorders, infection, or atelectasis.15

554

SECTION II—Diagnostic

Tests and Procedures

Reference Values
Normal Thoracic Gas Volume, Compliance, and Airway Resistance
Thoracic gas volume

2400 mL

Compliance

0.2 L/cm H2O

Airway resistance

0.6–2.5 cm H2O/L per sec

Note: No obstructive or restrictive lung disease, infection, or atelectasis.

Body plethysmography can be performed in
conjunction with pulmonary stress testing and
pulmonary function tests.
INTERFERING FACTORS

Inability of client to follow breathing instructions
during the procedure
INDICATIONS FOR BODY PLETHYSMOGRAPHY

Determining the status of obstructive pulmonary
disease (emphysema, asthma, chronic bronchitis)
revealed by an increased gas volume, compliance,
and airway resistance
Determining the status of restrictive pulmonary
disease such as fibrosis revealed by a decrease in
compliance, resulting from lung stiffness
Detecting acute pulmonary disorders such as
atelectasis and pneumonia by changes in compliance caused by congestion
Differentiating between obstructive and restrictive pulmonary pathology
Evaluating pulmonary status before pulmonary
rehabilitation to determine the baselines and
possible benefits from the therapy
CONTRAINDICATIONS

Extreme claustrophobia that prevents enclosure
in the box
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plethysmography procedure (see
section under “Arterial Plethysmography”).
Inform the client that the test is performed in an
enclosed box while the client is seated on a chair;
a soft clip is placed on the nose to assist in breathing through a mouthpiece.
Obtain and record client’s weight, height, gender,
and history including known or suspected
pulmonary conditions, associated diagnostic tests
and procedures, and treatment or medication
regimen.
THE PROCEDURE

The client is placed in a sitting position on a chair in

the body box. A nose clip is positioned to prevent
breathing through the nose and a mouthpiece is
placed in the mouth. The client is requested to
breathe through the mouthpiece, which is connected
to the transducer and the recorder device. The door
to the box is closed, and time is given for the pressure in the box to stabilize before the test is started.
The client is informed to notify the technician if
claustrophobia or breathing difficulties occur when
the client is requested to change breathing patterns.
At the beginning of the study, the client is requested
to pant without allowing the glottis to close. The box
and mouth pressures are recorded, and this information is used to calculate the thoracic gas volume.
The client is then requested to breathe in a rapid,
shallow pattern; the box pressure is recorded and
compared with the pressures recorded on the screen
and used to calculate airway resistance. If compliance is tested, a double-lumen catheter is inserted
into the esophagus via the nose, and the bag is
inflated with air. Intraesophageal pressure is
recorded during normal breathing to determine
intrapleural pressure, which is considered to be similar. The changes in the intraesophageal pressure
provide the information needed to determine lung
compliance.16
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as for any plethysmography study (see section
under “Arterial Plethysmography”). Allow the client
time to resume a normal breathing pattern.

OCULOPLETHYSMOGRAPHY
Oculoplethysmography is a manometric study to
measure blood flow in the ipsilateral orbit of the eye
in diagnosing carotid artery disease. The blood flow
in one eye is compared with that in the other eye to
determine decreases indicating pathology. The
blood flow of the carotid artery and circulation in
the brain are reflected by the blood flow of the
ophthalmic artery because of its connection to the
internal carotid artery.
The study can be performed in conjunction with

CHAPTER 22—Manometric

duplex scanning of the carotid arteries and followed
by cerebral angiography to diagnose blood-flow
patterns to the brain from the carotid arteries.
Reference Values
Normal blood flow in the carotid arteries; no
atherosclerotic occlusive disease
INTERFERING FACTORS

Inability of client to prevent blinking during the
procedure
INDICATIONS FOR OCULOPLETHYSMOGRAPHY

Determining the cause of transient ischemic
attacks (TIAs) and symptoms of neurological
disorders, such as syncope and ataxia
Diagnosing carotid atherosclerotic stenosis or
occlusive disease revealed by a reduced rate of
blood flow in the ophthalmic artery
Determining the extent of carotid stenosis
Evaluating carotid artery patency before or after
endarterectomy17
CONTRAINDICATIONS

Eye surgery as recent as 2 to 6 months before the
study
Clients with cataracts or lens implants
Clients who have had retinal detachment in the
past
Allergy to the local anesthetic used in the study
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as for any plethysmography procedure (see
section under “Arterial Plethysmography”).
Inform the client that the usual medications and
eyedrops are not restricted but that additional
eyedrops that cause a slight burning sensation will
be administered to anesthetize the eyes.
Remove contact lenses and store in a safe place.
Obtain baseline blood pressure in both arms.
Attach electrodes for ECG, if one is ordered.
Obtain a history that includes cardiovascular and
neurological status, known or suspected disorders
associated with the carotid artery, and results of
associated diagnostic tests and procedures.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The electrodes are connected and
the ECG machine is turned on to monitor for
arrhythmias when the study begins. After the
eyedrops have been administered in the amounts

Studies

555

and frequency ordered to anesthetize both eyes,
small photoelectric detectors are attached to both
earlobes. Pulsations from blood flow to the ears via
the external carotid arteries are detected, compared,
and recorded. Small suction cups are then attached
to both eyeballs and held in place with 40 to 50 mm
Hg of suction.18 Blood flow within each eye causes
pulsations that are detected and recorded. Blood
flow to each eye is interrupted temporarily by the
application of increased pressure to the eyeball.
When blood flow is resumed, pulsations are
recorded to determine whether the flow is simultaneous for both eyes. Blood flow to the eye is delayed
if carotid occlusive disease is present. The difference
in the timing of pulsations is measured in milliseconds. The study results are evaluated based on a
comparison of pulsations in one eye with those in
the other or of pulsations in one ear with those in
the other, or in some cases, of pulsations of one eye
with those of the ear on the opposite side. The delay
in blood flow measures the degree of carotid artery
disease as mild, moderate, or severe.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure include
advising the client to refrain from rubbing the eyes
for 2 hours and to gently blot tearing with a soft
tissue.
Inform the client that contact lenses should not be
replaced for 2 hours and that sunglasses can be
worn if temporary photophobia is experienced.
Explain that the eyes can appear bloodshot after
the study and that, if the eyes are irritated, drops
of artificial tears should be instilled.
Remind the client that the anesthetic wears off in
about 30 minutes.
Corneal abrasion: Note and report eye pain or
vision changes. Apply an ordered lubricant and an
eye bandage.
Conjunctival irritations and hemorrhage: Note
and report redness of conjunctiva and complaints
of pain. Apply ordered medications and treatments. Cover the eye with a bandage.

FETOPLACENTAL ADEQUACY
STUDIES
Fetoplacental studies involve the measurement of
placental blood flow to determine the adequacy of
placental reserve oxygen. They are performed to
detect high-risk pregnancies by identification of
intrauterine asphyxia as well as the effect of maternal diabetes, hypertension, Rh factor sensitization,
and other conditions on fetal status.
Two tests can be performed to determine
intrauterine hypoxia and to evaluate fetal well-

556

SECTION II—Diagnostic

Tests and Procedures

being: the contraction stress test and the nonstress
test. The nonstress test provides information about
fetal status based on fetal heart rate (FHR) acceleration during fetal movement in the absence of uterine
contractions. A fetal monitor is attached to the
mother and the FHR is monitored to obtain a reactive pattern, that is, two or more accelerations in a
10-minute period. Fewer than two accelerations are
rated as equivocal, and an absence of accelerations is
rated as nonreactive. The nonstress test can be
performed by a nurse, with the FHR strip interpreted by the nurse or physician. The stress test can
follow the nonstress test when the nonstress test is
rated as nonreactive. The stress test provides information about fetal status based on FHR during the
stress of uterine contractions, evaluating placental
reserve adequacy that allows the fetus to receive
adequate oxygen during uterine contractions. The
results are considered to be useful for a week in the
late stages of pregnancy or before labor.
Because nonstress tests are performed routinely,
only the contraction stress test procedure is fully
developed in this section.

INTERFERING FACTORS

CONTRACTION STRESS TEST

CONTRAINDICATIONS

The contraction stress test, also known as the
oxytocin (Pitocin) challenge test, is a manometric
study performed to measure the adequacy of the
placenta to provide oxygen to the fetus during the
stress of oxytocin-induced uterine contractions.
Uterine contractions normally produce a decrease in
placental blood flow, and in the later stages of pregnancy (at least 34 weeks’ gestation) this study can
predict whether a fetus might be at risk for
intrauterine asphyxia. The test can be repeated
weekly until the onset of labor and delivery if the
fetus is at risk for intrauterine hypoxia. An adequate
placental reserve, in which the blood flow is not
compromised and the FHR is within the normal
range, indicates a negative test, meaning that the
fetus is not in jeopardy and can tolerate the stress of
labor. A positive result is determined by consistent
late deceleration of the FHR during two or more
contractions and indicates an inadequate oxygen
supply to the fetus and a risk for uterine asphyxia. If
the late decelerations are not consistent, the test is
considered equivocal and is repeated in 24 hours.19
Only specially trained personnel can administer and
monitor this test.
Reference Values
Negative; no late deceleration in the FHR after a
contraction

Maternal hypotension, which can cause an inaccurate positive result
INDICATIONS FOR CONTRACTION STRESS TEST

Evaluation of the fetus at risk for hypoxia or the
effects of hypoxia and possible in utero or postpartum respiratory distress or death
Determination of the effects of maternal diabetes,
hypertension with toxemia on fetoplacental
adequacy, and fetal well-being
Past history of stillbirth, postmaturity birth,
intrauterine growth retardation, low estriol levels,
and Rh factor sensitization
A nonreactive result from a nonstress test to
determine the ability of the fetus to withstand
uterine contractions before labor begins
Assessment of possible impact of cesarean birth
on the fetus
Assessment of the need to terminate the pregnancy by labor inducement and early birth (in
conjunction with other diagnostic procedures
such as ultrasonography and amniocentesis)

Conditions that may increase the possibility of
early labor and birth or other danger to mother or
fetus:
Prematurely ruptured membranes
Multiple pregnancy
Previous transverse or classic cesarean birth or
other surgical hysterotomy
Previous premature labor
Abnormalities such as abruptio placentae or
placenta previa
Gestation of less than 34 weeks20
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure requires 2 hours
That food and fluid are withheld for 4 to 8 hours
before the study to prepare for possible premature
labor (This requirement is determined by agency
policy.)
That breathing and relaxation techniques will be
used during the study to allay the mild contractions that are induced to perform the test (Teach
these techniques to the client if she has not
attended childbirth class, and allow her to practice.)
That a monitor is placed on the abdomen to check
FHR, another monitor is placed on the lower
abdomen to check uterine contractions, and
blood pressure is monitored during the study

CHAPTER 22—Manometric

That uterine contractions are induced by the
intravenous (IV) administration of the hormone
oxytocin
That mild contractions are the only discomfort
experienced during the study
Prepare for the procedure:
Ensure that food and fluid restrictions have been
followed.
Obtain blood pressure and FHR for baselines to
use as a comparison during or after the study.
Have client void.
Obtain a history of past pregnancies, known and
suspected medical conditions, known and
suspected risks to the fetus and mother, previous
diagnostic tests and procedures, and medical
treatments for chronic disorders and those associated with the pregnancy.
THE PROCEDURE

The client is placed on the examination table or bed
in a semi-Fowler’s slightly side-lying position. The
client is draped for privacy. The blood pressure is
taken and the cuff is left on the arm to monitor the
pressure every 10 minutes during the procedure,
because a drop in blood pressure can affect the
placental blood flow and produce inaccurate results.
The fetal monitor is placed on the abdomen and a
tocodynamometer is placed on the lower abdomen
to monitor contractions. A baseline recording is
made of fetal heart tones and uterine contractions.
Continuous monitoring takes place for 20 minutes,
and a recording of the FHR and uterine movement
is obtained. A recording of FHR during spontaneous
uterine contractions should be obtained, but if no
contractions occur, IV oxytocin should be administered in the dilution and rate ordered by the physician, with the rate regulated by an infusion pump.
The rate is increased until three contractions per
minute are noted. FHR and contractions are then
monitored and recorded and the infusion discontinued to determine the FHR response to the stress of
the contractions. The client is advised to use the
deep-breathing exercises learned in childbirth class
to control any discomfort from the contractions.
Monitoring of the FHR is continued for 30 minutes

Studies

557

(the time it takes to metabolize the oxytocin) as the
uterine movements return to normal.
Another procedure to stimulate oxytocin for the
contraction stress test in clients after 26 weeks’ gestation is the breast stimulation test. This test releases
oxytocin by stimulation of the nipples instead of IV
administration of the drug. The stimulation creates
nerve impulses to the hypothalamus, causing the
release of oxytocin into the bloodstream, which
results in uterine contractions. The same monitoring and recording are performed when sufficient
contractions have been obtained.21
NURSING CARE AFTER THE PROCEDURE

Help the client dress, if help is needed. Monitor
the blood pressure and FHR and compare with
baseline values.
Remove the IV catheter.
Assess the site for pain, swelling, redness, and
bleeding; apply a dressing.
Premature labor: Note and record frequency,
strength, and continuation of contractions.
Prepare for first stage of labor or cesarean birth.
REFERENCES
1. Thomas, CL (ed): Taber’s Cyclopedic Medical Dictionary, ed 18. FA
Davis, Philadelphia, 1997, p 1160.
2. Fischbach, FT: A Manual of Laboratory Diagnostic Tests, ed 4. JB
Lippincott, Philadelphia, 1992, p 909.
3. Porth, CM: Pathophysiology: Concepts of Altered Health States, ed
5, JB Lippincott, Philadelphia, 1998, p 687.
4. Pagana, KD, and Pagana, TJ: Mosby’s Diagnostic and Laboratory
Test Reference. Mosby–Year Book, St Louis, 1992, p 258.
5. Ibid, p 259.
6. Ibid, p 260.
7. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, pp 981–982.
8. Ibid, p 982.
9. Pagana and Pagana, op cit, p 317.
10. Porth, op cit, p 722.
11. Fischbach, op cit, p 910.
12. Ibid, p 910.
13. Pagana and Pagana, op cit, p 567.
14. Ibid, p 569.
15. Ibid, pp 832–833.
16. Fischbach, op cit, p 833.
17. Pagana and Pagana, op cit, p 530.
18. Nurse’s Reference Library, op cit, p 764.
19. Pagana and Pagana, op cit, p 229.
20. Ibid, p 230.
21. Ibid, p 232.

CHAPTER

Electrophysiologic
Studies
TESTS COVERED
Electrocardiography, 559
Holter ECG, 562
Phonocardiography, 563
Exercise ECG, 564
Signal-Averaged Electrocardiography, 565
Pelvic Floor Sphincter Electromyography,
566

Electromyography, 567
Electroneurography, 568
Electroencephalography, 569
Evoked Brain Potentials, 571
Electronystagmography, 573
Electroretinography, 574
Electro-Oculography, 575

INTRODUCTION

Electrophysiologic studies are procedures that use electric and electronic devices in the diagnosis of tissue and organ pathology. They measure electric events for
indirect assessment of the structure and function of an organ. Assessment is based on a determination of the effects of electric stimulation on tissues, the production of electric currents by
organs and tissues, and the results of the therapeutic use of electric currents.1 Electrodes are
attached to a portion of the body to measure the current or activity produced by the examined
organ or tissue to identify pathology. The studies produce an electrogram, a graphic display or
recording of electric activities produced by tissues or organs, for analysis and diagnostic information.
The studies are most commonly used in the investigation of heart, muscle, and nerve abnormalities. They are performed on inpatients or outpatients in specially equipped rooms; in a
physician’s office; or, for some studies, at the bedside by a physician or a technician, depending
on the procedure. All except electromyography and studies that use needle insertions are
considered noninvasive procedures with little or no risk to the client and do not require a signed
informed consent form.

ELECTRODIAGNOSTIC STUDIES
Electrodiagnostic procedures are named for the
organ or region of the body to be examined, including the heart, brain, eye, and muscle. Depending on
the organ or region to be studied, electrodes are
558

placed and positioned on the skin over the area
containing the organ or directly on the organ. The
studies are performed to support and extend information obtained from other diagnostic procedures
for diagnosing or evaluating congenital and
acquired diseases of the involved organs, that is,

CHAPTER 23—Electrophysiologic

physical assessment and history, ultrasonography,
radiography, angiography, and computerized scanning.

ELECTROCARDIOGRAPHY
Electrocardiography (ECG) is an electrophysiologic
study that measures the electric currents or impulses
that are generated by the heart during a cardiac
cycle. The heart has the ability to produce impulses
and contractions, and these impulses and contractions are able to conduct electric currents that flow
throughout the body. The electric activity is
recorded in waveforms and complexes by an ECG
and are analyzed with time intervals and segments.
Continuous tracing of all activities of each cardiac
cycle is captured as heart cells are electrically stimulated, causing depolarizations and movement of the
activity through the cells of the myocardium. The
electric impulses that are generated are conducted
via the fluid-containing tissues of the body to the
surface and to the electrodes that are positioned in
strategic places on the chest and extremities.2
Analysis of the tracings obtained reveals varied diagnostic information about cardiac function.
The components of the cardiac cycle that are
displayed and recorded and that serve as a basis for
analysis of the ECG are the P, Q, R, S, T, and U waves
(Fig. 23–1). The Q, R, and S waves are grouped and
represent the QRS complex. Measurements are
made in seconds or numbers of blocks (squares) on
the tracing paper.
1. P waves record atrial depolarization as the
impulse from the sinoatrial (SA) node spreads

Figure 23–1. Wave, interval, and segment of the
cardiac cycle.

Studies

559

through the atria to produce an atrial contraction. When present and normal in amplitude
and width, the waves confirm that the impulse
originated in the SA node and not in an area
outside the node.
QRS complex waves record ventricular depolarization associated with a ventricular contraction. On the tracing in sequence, the Q
wave is a small, downward or negative deflection; the R wave is a large, pointed, upward or
positive deflection; and the S wave is a small,
downward deflection. Any abnormal widening
of this complex indicates a prolonged ventricular depolarization time.3
T waves record a period of ventricular repolarization with no electric activity after the QRS
complex and they appear before another
cardiac cycle begins.
The PR interval is the time it takes for the
impulse from the SA node to travel to the
ventricle or atrioventricular (AV) node. It is
the measured time between atrial depolarization (P wave begins) and onset of ventricular
depolarization (QRS complex begins). A
prolonged time indicates a delay in conduction
activity.
QT or QRS interval is the time it takes for
ventricular depolarization (Q wave begins)
and repolarization (S wave ends).
ST segment is the period between the end of
depolarization and the beginning of repolarization of the ventricular contraction.
PR segment is the period from the end of the P
wave to the beginning of the QRS complex.

The ECG study is performed using 10 leads (electrodes) attached to the skin surface to obtain the
total electric activity of the heart. Each lead records
the electric potential between the limbs or between
the heart and the limbs. The tracings are recorded on
graph paper with vertical and horizontal lines for
analysis. Time calculations are measured by the
vertical lines (1 mm apart and 0.04 seconds per line),
and voltage is measured by the horizontal lines (1
mm apart and 0.5 mV per 5 squares).4 Pulse rate can
be determined from the ECG strip by counting the
number of large squares between each QRS complex
and multiplying this number by 0.20 seconds (1
large square). To obtain the beats per minute, divide
the result into 60 (the number of seconds in a
minute).5
Vectorcardiography is another form of ECG; it
has the ability to portray a three-dimensional display
of the heart’s activity as opposed to the two-dimensional display of the conventional ECG. The ECG

560

SECTION II—Diagnostic

Tests and Procedures

records activity in the frontal and horizontal planes,
and vectorcardiography records activity in the
frontal, horizontal, and sagittal planes. The instrument displays three loops (P, QRS, and T) on
the screen for each complete cardiac cycle. These
loops correspond to the same waves on the ECG,
and the loop configurations can be recorded or
photographed for analysis. This procedure is considered to be more sensitive and more specific in diagnosing such diseases as myocardial infarct and
ventricular hypertrophy.6
Apexcardiography is a study that can be
performed simultaneously with ECG or phonocardiography to record chest movements resulting
from cardiac impulses. This study uses a transducer
placed at the apical site that converts the impulses
into waveforms recorded on an apexcardiogram.7
The recording can be accompanied by tracings from
the ECG and other procedures on the apexcardiogram and can provide additional information about
the cardiac cycle in diagnosing ventricular abnormalities.
INTERFERING FACTORS

Improper placement of electrodes, especially in
conjunction with abnormal chest configuration
or heart location within chest cavity; inadequate
contact between skin and electrodes by ineffective
conductive jelly or seal
ECG machine malfunction or interference from
electromagnetic rays in the vicinity
Inability of client to remain still during the procedure
Strenuous exercise before the procedure
High level of anxiety and deep respirations or
hyperventilation

High intake of carbohydrates; electrolyte imbalances of potassium or calcium
Distortions in cardiac cycle caused by age and
gender, especially if the client is an infant or a
woman
Obesity, ascites, and pregnancy
Medications such as barbiturates and digitalis
preparations
INDICATIONS FOR ELECTROCARDIOGRAPHY

Identification and diagnosis of cause of arrhythmias as revealed by abnormal wave deflections
Determination of heart rate
Determination of conduction defects or diseases
revealed by delay of electric impulses, with abnormal time duration and amplitude of waves and
intervals recorded on the strip
Determination of the site and extent of myocardial or pulmonary infarction and myocardial
ischemia revealed by abnormal wave and interval
times and amplitudes
Determination of hypertrophy of chambers of the
heart (atrial and ventricular) or heart hypertrophy
Determination of the position of the heart in the
thoracic cavity
Diagnosis of pericarditis and Wolff-ParkinsonWhite syndrome revealed by ventricular pre-excitation caused by accelerated AV conduction and
changes in the QRS complex
Suspected electrolyte imbalances of potassium,
calcium, and magnesium and their effect on the
heart
Evaluation of drugs such as digitalis preparations
and antiarrhythmics, vasodilators, and antihypertensives

Reference Values
Normal heart rate according to age, 60 to 100 beats per minute in adults
Normal regular rhythm and wave deflections with normal measurement ranges of cycle components and
height, depth, and duration of complexes:
P wave: 0.12 seconds, or three small blocks, with amplitude of 2.5 mm
Q wave: less than 0.04 seconds
R wave: amplitude range of 5 to 27 mm, depending on lead
T wave: amplitude range of 1 to 13 mm, depending on lead
QRS complex: 0.12 seconds, or three small blocks
PR interval: 0.2 seconds, or five small blocks
ST segment: 1 mm
No arrhythmias, myocardial infarction, electrolyte imbalances, myocardial ischemia, chamber hypertrophy, or conduction abnormalities
No myocardial infarction or ventricular hypertrophy with vectorcardiography
No ventricular or heart sound abnormalities with apexcardiography

CHAPTER 23—Electrophysiologic

Evaluation of cardiac pacemaker function
Monitoring of myocardial infarction during
recovery
Differentiation between possible causes of intraventricular conduction abnormalities and
ventricular hypertrophy by vectorcardiography
Suspected ventricular abnormalities
Nursing Alert

If the ECG changes indicate severe ischemia
or necrosis associated with myocardial infarction, immediate interventions should be
carried out, such as administration of oxygen,
sedation, antiarrhythmics, vasodilators, and
other medications to control coronary artery
spasms and tachycardia.

NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure requires 15 minutes
That there are no food or fluid restrictions but
that smoking may be disallowed before the test
That electrodes are attached to the skin of the
chest, arms, and legs with a paste or pads and
connected to the wires and ECG machine
That the electric impulses from the heart are
transmitted from the body and that no electricity
is delivered to the body
That no discomfort is associated with the procedure
Prepare for the procedure:
Obtain a history of known or suspected cardiac
disorders and present cardiovascular status,
medication regimen, and associated diagnostic
laboratory tests and procedures.
Ensure that assessment of the cardiovascular
system has been performed for use in interpretation of the study.
THE PROCEDURE

The client is placed on an examination table or in a
bed in a supine position. The chest, arms, and legs
are exposed and proper draping is done for privacy.
A 5-minute rest period is allowed before the procedure. The sites for electrode placement are cleansed
with alcohol. Excessive hair on the skin can be
shaved, if necessary. The skin sites are dried and electrode paste is applied to provide conduction
between the skin and the electrode. The electrodes
are strapped in place on the extremities and placed
in proper positions on the chest. Some newer electrodes do not require paste to be applied to the skin,

Studies

561

because the backing is prepared with an adhesive
electropaste that provides the conduction. The electrodes are color coded for placement sites (chest,
right and left arm, and right and left leg) and
matched to coded lead wires with the sites labeled.
The wires are connected to the matched electrodes
and the ECG machine.
Ten leads are used in ECG to obtain and record
the flow of electric impulses in different planes. Six
unipolar precordial leads are placed on the chest:
V1 at the fourth intercostal space at the border of
the right sternum, V2 at the fourth intercostal space
at the border of the left sternum, V3 between V2
and V4, V4 at the fifth intercostal space at the
midclavicular line, V5 at the level of V4 horizontally
and at the left axillary line, V6 at the level of V4
horizontally and at the left midaxillary line.8 Three
bipolar limb leads (two electrodes combined for
each) are placed on the arms and legs. Lead I is the
combination of two arm electrodes, lead II is the
combination of the right arm and left leg electrodes, and lead III is the combination of left arm
and left leg electrodes.9
The client is reminded to lie still and to refrain
from tensing muscles after electrode placement. The
machine is set and turned on after the electrodes,
grounding, connections, and paper supply are
checked. The ECG machine records and marks the
10 leads on the strip in proper sequence, usually 6
inches of the strip for each lead.
The procedure is the same for vectorcardiography. Apexcardiography, which can be performed in
conjunction with ECG or vectorcardiography, is
performed by the placement of a transducer with
electropaste over the apex of the heart or at the point
of maximal impulse. The client is placed in the left
side-lying position and is requested to perform
different exercises such as breathing slowly, holding
the breath, and using handgrips to determine the
effect of these activities on ventricular function. The
pulsations that are obtained by the transducer are
converted to electric energy and recorded as waveforms that are identified as periods of systole and
diastole on the paper strip.10
NURSING CARE AFTER THE PROCEDURE

Remove the electrodes from the skin sites and
cleanse the paste from the skin.
Monitor the heart rate, rhythm, and pulse deficit
for possible arrhythmias or in instances of chest
pain experienced and noted on the strip during
the procedure.
Decreased cardiac output: Note and report
peripheral pulses, skin color, capillary refill time,

562

SECTION II—Diagnostic

Tests and Procedures

dyspnea, abnormal heart sounds, angina, or
decreased urinary output. Administer ordered
oxygen and cardiac medications.
Arrhythmias: Note and report cardiac rhythm
abnormalities on the strip. Administer ordered
oxygen, vasodilators, and antiarrhythmics if
infarction or ischemia, life-threatening arrhythmias, or ventricular tachycardia is revealed.

Evaluating antiarrhythmic medications
Monitoring for ischemia and arrhythmias after
myocardial infarct or cardiac surgery
Evaluating cardiac rehabilitation and other therapy regimens
Evaluating pacemaker function
CONTRAINDICATIONS

Clients who are unable or unwilling to maintain
the electrodes and ECG apparatus and the daily
log of activities and symptoms

HOLTER ECG
Holter ECG, also known as ambulatory ECG monitoring, is an electrophysiologic study performed to
record cardiac activity on a continuous basis for 24
to 48 hours. It is performed to identify rhythm
abnormalities, to relate them with symptoms experienced by the client, and to evaluate the effectiveness
of medication regimen and pacemaker function.
The study includes the use of a portable device worn
around the waist or over the shoulder that records
cardiac electric impulses on a magnetic tape. The
recorder has a clock that allows accurate time markings on the tape. When the client pushes a button
indicating that symptoms (pain, palpitations, dyspnea, or syncope) have occurred, an event marker is
placed on the tape for later evaluation. The study
monitors heart activities during different types of
daily activities engaged in by the client, such as
sleeping, resting, walking, and working. Tapes are
played back, interpreted, and summarized by a
computer. The results can also be compared with
data collected from documentation by the client in a
journal and with the event markers on the tape,
either of which can indicate the symptoms experienced during the monitoring period.
Reference Values
Normal sinus rhythm; no arrhythmias such as
premature ventricular contractions, bradyarrhythmias, or tachyarrhythmias
INTERFERING FACTORS

Improper placement of the electrodes or movement of the electrodes
Failure of client to maintain a daily log of symptoms or to push the button to produce a mark on
the strip when experiencing a symptom
INDICATIONS FOR HOLTER ECG

Detecting arrhythmias that occur during normal
daily activities and correlating them with symptoms to determine whether they are caused by
cardiac rhythm abnormalities

NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Electrocardiography” section.
Inform the client that the wires from the electrodes on the chest are connected to a portable
ECG machine that is worn over the shoulder or
on a belt at the waist for 24 to 48 hours.
Instruct the client to avoid contact with electric
devices such as shavers and toothbrushes, tightfitting clothing over the electrodes, bathing, and
disturbing or disconnecting the electrodes or
wires.
Instruct the client to maintain a log noting
normal activities such as walking, sleeping, climbing stairs, sexual activity, cigarette smoking, and
bowel or urinary elimination.
Instruct the client to enter any symptoms experienced, such as chest pain, dizziness, fatigue, dyspnea, syncope, palpitations, or emotional upsets
and to push the button on the monitor when
these symptoms occur.
Advise the client to return to the laboratory with
the log to have the machine and strip removed
and interpreted.
Reassure the client that no electricity is delivered
to the body during this procedure and that no
discomfort is experienced during the monitoring
process.
Obtain a history that includes known or
suspected cardiac disorders, cardiac medication
regimen, and previous diagnostic tests and procedures.
THE PROCEDURE

The client is placed on the examination table in a
supine position. The chest is exposed and the skin
sites thoroughly cleansed with alcohol and rubbed
until red in color. Excessive hair on the skin can be
shaved. Electropaste is applied to the skin sites to
provide conduction between the skin and the electrodes. Disk electrodes that are prelubricated and

CHAPTER 23—Electrophysiologic

disposable can also be applied. The electrodes are
applied over bony prominences rather than muscular areas, two on the manubrium (negative electrodes) and two in the V1 (fourth intercostal space at
the border of the right sternum) and V5 (fifth intercostal space at the midclavicular line, horizontally
and at the left axillary line) positions (positive electrodes).11 A ground electrode is also placed and
secured to the skin of the chest or abdomen. Check
that the electrodes are secure; then attach the electrode cable to the monitor and the lead wires to the
electrodes. The monitor is checked for paper supply
and battery, the tape is inserted, and the recorder
turned on. All wires are taped to the chest, and the
belt or shoulder strap is placed in the proper position.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study include
removing the tape and electrodes and cleansing
the electropaste from the skin sites.
Remove the monitor and retrieve the tape for
analysis by the physician.

PHONOCARDIOGRAPHY
Phonocardiography is an electrophysiologic study
performed to identify, amplify, and record heart
sounds and murmurs. The sounds of blood flowing
through the heart and great vessels are recorded
from sites on the chest by a microphone containing
a transducer that converts the sounds into electric
impulses. Selected high- and low-frequency events
are recorded on a graph. This recording is performed simultaneously with the ECG, and monitoring of the respiratory cycle and external
cardiovascular impulse such as the carotid pulse,
jugular venous pulse, and apexcardiography. They
provide an accurate timing of the heart sounds and
events for the detailed analysis of heart sounds,
murmurs, and impulses that is not possible by
bedside examination with a stethoscope. The
phonogram allows visualization of the total duration of the cardiac cycle and valvular events when
performed alone or in conjunction with the carotid
or jugular pulse or with apexcardiography.
Information is provided about the fourth heart
sound (S4), first heart sound (S1), mitral valve
closure, tricuspid valve closure, pulmonic valve
closure, tricuspid valve opening, mitral valve opening, opening snap, third heart sound (S3), and
systolic time intervals.12 Abnormalities in any of
these events assist in the diagnosis of valvular heart
disease and cardiomyopathies.

Studies

563

Reference Values
Normal heart sounds; no cardiac valvular
disease
INTERFERING FACTORS

Improper placement of the microphone on the
chest, background noises, or other interferences
The same factors that affect accurate results of
ECG (see “Electrocardiography” section).
INDICATIONS FOR PHONOCARDIOGRAPHY

Detecting valvular defects revealed by abnormal
heart sounds: increased intensity of the first
sound (S1), heard in tricuspid or mitral stenosis,
or lower frequency of the fourth sound (S4), heard
in aortic stenosis
Differentiating between mitral and tricuspid
opening snaps from the third sound (S3) as
revealed by a higher frequency of the snaps in
phonocardiography
Differentiating among early, mid, and late systolic
murmurs
Diagnosing hypertrophic cardiomyopathies and
pulmonary hypertension revealed by the presence
of the fourth sound (S4) and murmurs
Diagnosing abnormal left ventricular function
revealed by changes in systolic time interval ratio,
that is, left ventricular ejection and pre-ejection
time
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Electrocardiography” section.
Provide the client with additional information
about the microphone strapped to the chest, position changes, and the need to perform several
activities during the ECG procedure.
Inform the client that other tests may be
conducted during the procedure, such as carotid
pulse and respiration recordings, and that the
total study time is about 30 minutes.
THE PROCEDURE

The client is placed on the examination table in
a supine position with the head elevated on a pillow
in a quiet room. The ECG leads are placed on the
appropriate skin sites, and the monitors for the
pulse, using a cuff around the neck and respiration
recordings, are prepared. The microphones are
then placed over the apex and pulmonary region
and strapped in place. The client is requested to

564

SECTION II—Diagnostic

Tests and Procedures

inhale and then exhale, while stopping the expiration as the recording is obtained. The microphone is
moved from the pulmonary region to the aortic
region and the procedure is repeated to obtain
the recording. These recordings are followed by
recordings made with the cuff removed from the
neck and the recorder placed at the V2 position
(fourth intercostal space at the border of the left
sternum) while the client is requested to hold the
breath after exhaling.13 Heart sounds can also be
recorded with the client in a different position (left
side-lying) and while breathing slowly or performing exercises.
NURSING CARE AFTER THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Electrocardiography” section.

EXERCISE ECG
Exercise ECG, also known as the stress test, is an
electrophysiologic study performed to measure
cardiac function during physical stress. It is
performed to assist in diagnosing coronary artery
disease (CAD) and to evaluate the safe level of activity or activity tolerance for work or cardiac rehabilitation. The physical stress is provided by walking on
a treadmill, climbing stairs, or pedaling an exercise
bicycle, with the treadmill most commonly used.
The heart, pulse, and blood pressure are monitored
continuously during the procedure by ECG, pulse,
and blood pressure devices. The client exercises to 80
to 90 percent of the maximal heart rate determined
by age and gender. This rate is known as the target
heart rate.14 Changes in the ECG (arrhythmias),
blood pressure (hypotension), pulse (tachycardia),
respirations (dyspnea), and symptoms such as chest
pain and extreme fatigue during the procedure indicate a reduction in cardiac efficiency and presence of
or risk for heart disease. The test is discontinued if
these abnormalities occur. The risks involved in the
procedure are possible myocardial infarct and death
in those experiencing frequent anginal episodes
before the test.
Although useful, this procedure is not as accurate
in diagnosing CAD as are the nuclear scans, thallium
201 (201Tl) cardiac stress studies (see Chapter 20), or
multiple gated cardiac stress studies using technetium 99m (99mTc) labeled with red blood cells
(see Chapter 20). Exercise ECG is primarily useful in
determining the extent of coronary artery occlusion
as indicated by the heart’s ability to meet the need
for additional oxygen in response to the stress of
exercising.

Reference Values
Normal heart rate during physical exercise; no
cardiac abnormalities on the ECG or presence of
associated symptoms at 80 to 90 percent of
maximal heart rate based on client age and
gender
INTERFERING FACTORS

Improper placement of electrodes, improper
conduction, or improper ECG machine function
High food intake or smoking before the testing
Medications such as -blockers, cardiac glycosides, calcium channel blockers, and coronary
vasodilators
Cardiac conditions such as hypertension, valvular
heart defects, left bundle branch block, left
ventricular hypertrophy, and other conditions
such as anemia, hypoxia, and chronic obstructive
pulmonary disease15
INDICATIONS FOR EXERCISE ECG

Suspected CAD in the presence of chest pain and
other symptoms
Screening for CAD in the absence of pain and
other symptoms in those who are at risk
Diagnosis of heart abnormalities such as tachycardia, bradycardia, and arrhythmias during exercising as revealed by ECG changes
Evaluation of cardiac function after myocardial
infarction or cardiac surgery in order to determine safe cardiac rehabilitation exercise and work
limitations
Determination of hypertension as a result of exercise
Detection of peripheral arterial occlusive disease
(intermittent claudication) revealed by leg pain or
cramping during exercise
Evaluation of effectiveness of medication regimens: antianginals or antiarrhythmics
CONTRAINDICATIONS

Frequent anginal episodes or presence of chest
pain
Myocardial infarction unless limitations are
placed on testing activities
Uncontrolled arrhythmias, dissecting aortic
aneurysm, aortic valvular disease, or inflammatory conditions of the cardiac muscles
Inability of client to walk or pedal because of
motor disability or impaired lung function
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the

CHAPTER 23—Electrophysiologic

same as those described in the “Electrocardiography” section.
Food, fluids, and smoking are avoided for at least
4 hours before the test.
Instruct the client to wear comfortable shoes and
clothing for the exercises and inform the client
that fatigue, sweating, and breathlessness can
occur during the test as the speed is increased.
Inform the client that a total time of 45 to 90
minutes is needed to complete the procedure.
Provide assurance that the test has very few risks
and that exercising can be terminated if extreme
symptoms occur.
Instruct the client to discontinue specific medications that interfere with test results before the
study.
Obtain baseline vital signs and ECG to use as a
comparison in evaluating the study.
THE PROCEDURE

The skin sites are cleansed with alcohol and rubbed
until red and the electrodes are placed in the appropriate positions. Clothing from the waist up is
removed from a male client, and a hospital gown
that opens in the front can be worn by a female
client. A physician is in attendance during this
study. A blood pressure cuff is applied to the arm
and connected to a monitoring device. Oxygen
consumption using a mouthpiece can also be monitored continuously by blood pressure and ECG. A
baseline ECG tracing and a blood pressure reading
are obtained. Heart sounds are auscultated and
recorded if the physician requests or performs this
physical assessment. The client is requested to walk
on a treadmill (most commonly used) or pedal a
bicycle after the setting of the apparatus to stages of
increased grade and miles per hour. As the stress is
increased, the client is requested to report any symptoms such as chest or leg pain, dyspnea, or fatigue.
The stress is increased until the client’s maximal
heart rate is reached. The client is reminded that
symptoms such as dizziness or nausea can be experienced and are normal. The test is terminated if pain
or fatigue is severe or when maximum heart rate
under stress is attained. A 3- to 10-minute rest
period in a sitting position follows the exercise
period, during which time the ECG, blood pressure,
and heart rate are monitored. The results are read
and interpreted by the physician.
NURSING CARE AFTER THE PROCEDURE

Provide a period of rest and monitor vital signs
and ECG in 3-, 10-, and 30-minute intervals.
Remove the electrodes and paste and cleanse the
skin sites.

Studies

565

Cardiac arrhythmias: Note and report abnormal
ECG cardiac cycle impulses. Terminate test and
administer ordered medication (antiarrhythmics).
Myocardial infarction: Note and report chest
pain and abnormal ECG recordings, pallor, skin
mottling, and diaphoresis. Terminate test and
administer ordered oxygen and medications
(morphine sulfate).
Anginal pain: Note and report chest pain, fatigue,
and cyanosis. Terminate test and administer
ordered oxygen and medications (vasodilators).
Dizziness or fainting: Note and report extreme
faintness, confusion, and dizziness. Terminate test
and allow the client to sit on a chair. Administer
an ordered stimulant.

SIGNAL-AVERAGED
ELECTROCARDIOGRAPHY
Signal-averaged electrocardiography is an electrophysiologic study performed to determine the risk
for ventricular arrhythmias in those clients who
have experienced myocardial infarction. It is similar
to conventional ECG except that the electrodes are
placed at different sites and a computer is used to
supply signal averaging, amplification, and electric
potentials. These readings are analyzed to provide
diagnostic information about late potentials (signals
produced by the myocardium) based on the averaging of a large number of heartbeats. The late potentials then are evaluated in the diagnosis of
myocardial pathology and sustained ventricular
tachycardia that can place a client at risk for sudden
death. The study can be followed with the His
bundle electrophysiology study by cardiac catheterization if findings are not definitive for ventricular
tachycardia (see Chapter 24).16
Reference Values
Normal complex (QRS) and segment (ST); no
ventricular arrhythmias or risk for arrhythmias
INTERFERING FACTORS

Improper placement of electrodes or inadequate
contact between the skin and the electrodes
Inability of client to remain quiet during the
procedure
Electrical equipment in the vicinity
Conditions such as ventricular tachycardia and
bundle branch block, which affect obtaining late
potentials and impulse averaging
Insufficient time to obtain heartbeats if the rate is
slow or if ectopic beats are present17

566

SECTION II—Diagnostic

Tests and Procedures

INDICATIONS FOR SIGNAL-AVERAGED
ELECTROCARDIOGRAPHY

Screening of high-risk clients for arrhythmias,
especially individuals with postmyocardial infarct
and those in need of His bundle study to diagnose
ventricular tachycardia
Unexplained symptoms such as syncope that
could be caused by ventricular tachycardia
Diagnosis of CAD as revealed by late potentials
Determination of sustained ventricular tachycardia and potential for sudden death, which are
associated with late potentials
Diagnosis of delayed conduction in the
myocardium in conditions such as infarction,
hypertrophic cardiomyopathy, ventricular
aneurysm, and congenital ventricular defects
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Electrocardiography” section.
Inform the client that electrodes will also be
placed on the abdomen and on the front and back
of the chest and that the study takes 20 to 30
minutes.
THE PROCEDURE

The client is prepared in the same way as for ECG
(see “Electrocardiography” section). The electrodes
are placed on the abdomen and on the anterior and
posterior areas of the chest. The high-frequency,
low-amplitude signals from the cardiac myocardium
are converted into digital signals, which are
compared with normal cardiac cycle signals, mainly
the QRS complex. A number of heartbeats are averaged to obtain late potentials, which are indicative of
ventricular tachycardia, other ventricular abnormalities, or myocardial infarction.
NURSING CARE AFTER THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Electrocardiography” section.
Arrhythmias: Note and report cardiac rhythm
abnormalities on the strip. Administer ordered
oxygen, vasodilators, and antiarrhythmics if
infarction or ischemia, life-threatening arrhythmias, or ventricular tachycardia is revealed.

PELVIC FLOOR SPHINCTER
ELECTROMYOGRAPHY
Pelvic floor sphincter electromyography, also known
as rectal electromyography, is an electrophysiologic
study performed to measure and record the

adequacy of urinary or anal sphincter muscle function. Rectal muscle pressure is usually performed to
measure abdominal pressure. Urethral muscle pressure is performed to evaluate the neuromuscular
function of the external sphincter during urination
to determine the flow rate and other urinary pattern
disturbances. The external sphincter muscle
surrounds the urethra distal to the bladder base and
functions to terminate urination while it occurs and
to maintain continence when bladder pressure
increases as the bladder fills with urine. Muscles
located on the pelvic floor support the bladder and
also contribute to continence.18 Electrodes are placed
on the surface of or within the muscle to be tested
and recordings are made of muscle activity before
and during the process of voiding. The recordings are
evaluated for changes that indicate neurogenic bladder or other urinary dysfunctions such as incontinence. The study can be performed in combination
with manometric urodynamic studies such as
cystometry, uroflowmetry, or urethral pressure
profile (see Chapter 22 for these three procedures).
Reference Values
Normal urinary and anal sphincter muscle function; increased electromyographic signals
during the filling of the urinary bladder and at
the conclusion of voiding; absence of signals
during the actual voiding; no incontinence
INTERFERING FACTORS

Inability of client to remain still or to cooperate
with requests for movement during the procedure
Improper placement of surface or needle electrodes
INDICATIONS FOR PELVIC FLOOR SPHINCTER
ELECTROMYOGRAPHY

Evaluation of lower urinary sphincter muscle
function during voiding to diagnose neuromuscular dysfunction
Evaluation of voluntary sphincter muscle activity
and pelvic floor muscles in the presence of incontinence or other urinary problems
Suspected detrusor hyperreflexia in neuromuscular dysfunction
Ruling out of psychological factors in urinary
dysfunction
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure requires 30 minutes
That there are no food, fluid, or other restrictions
before the study

CHAPTER 23—Electrophysiologic

That electrodes are placed on the perineal area
and the leg or that needles are inserted into the
muscle and that recordings are made during the
procedure
That discomfort is minimal from the insertion of
the catheter and the testing of muscle activity
Prepare for the procedure:
Obtain a history of neuromuscular and genitourinary status, medical treatment and medication
regimens, and previous tests and procedures
performed for urinary function.
Have client void immediately before the study.
THE PROCEDURE

The client is placed on the examination table in a
supine position and draped to expose the perineal
area. Two skin electrodes are positioned at the perianal area slightly to the left and right of the anterior
portion, and a grounding electrode is placed on the
thigh. If needle electrodes are used, they are inserted
into the muscle surrounding the urethra. Muscle
activity signals are recorded as waves that are interpreted for numbers and configurations in diagnosing urinary abnormalities. The client is reminded to
lie quietly and relax. A Foley catheter is inserted and
the bulbocavernous reflex is tested by asking the
client to cough while the catheter is carefully tugged.
Then voluntary control is tested by asking the client
to contract and relax the muscle. Electric activity is
recorded during this period of relaxation with the
bladder empty. The bladder is filled with 100 mL of
sterile water per minute while the electric activity
during filling is recorded. The catheter is then
removed; the client is placed in a position to void
and is requested to urinate to empty the full bladder.
This voluntary urination is then recorded until
completed. The complete test includes recordings of
electric signals before, during, and at the end of
urination.19
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study include
removal of the electrodes and cleansing of the
sites.
Monitor the sites for pain, redness, swelling, and
hematoma if needle electrodes are used.
Inflammation from needle electrodes: Note and
report pain, swelling, and redness at the insertion
sites. Administer an ordered analgesic. Apply
warm compresses.

ELECTROMYOGRAPHY
Electromyography (EMG) is an electrophysiologic
study performed to determine the electric activity of

Studies

567

specific muscles to assist in the diagnosis of muscular diseases and the effects of other diseases on
muscles. Skeletal muscle activity is measured during
rest, voluntary contraction, and electric stimulation.
Comparison and analysis of the amplitude, duration, number, and configuration of the muscle activity provide diagnostic information about the extent
of nerve and muscle involvement in neuromuscular
disorders. Responses of a relaxed muscle are electrically silent, but fibrillation and fasciculations can be
detected in a relaxed denervated muscle. Muscle
action potentials are detected with minimal or maximal muscle contractions. The differences in the size
and numbers of activity potentials during voluntary
contractions determine whether the muscle weakness is myogenic or neurogenic.20 A signed informed
consent form is required for this study.
Nerve conduction studies or electroneurography
(see later section) is commonly performed in
conjunction with EMG and the combination of the
procedures is known as electromyoneurography.
This study is performed to assist in diagnosing
diseases of and damage to the peripheral nerves. It
can test both motor and sensory nerve abnormalities.
Reference Values
Normal muscle electric activity during rest and
contraction states; no neuromuscular disorders
or primary muscle diseases
INTERFERING FACTORS

Inability of client to remain still and to cooperate
with instructions during the procedure
Hemorrhage, edema, excessive subcutaneous fat,
and pain
Increased age
Medications such as muscle relaxants, cholinergics, and anticholinergics
INDICATIONS FOR ELECTROMYOGRAPHY

Diagnosing primary muscle diseases affecting
striated muscle fibers or cell membrane: muscular
dystrophy or myasthenia gravis
Diagnosing secondary muscle disorders caused by
polymyositis, sarcoidosis, hypocalcemia, thyroid
toxicity, tetanus, and other disorders
Diagnosing neuromuscular disorders such as
peripheral neuropathy caused by diabetes or alcoholism
Diagnosing muscle disorders caused by diseases of
the lower motor neurons involving the motor
neurons on the anterior horn of the spinal cord:
anterior poliomyelitis, amyotrophic lateral sclerosis, amyotonia, or tumors

568

SECTION II—Diagnostic

Tests and Procedures

Diagnosing muscle disorders caused by diseases of
the lower motor neuron involving the nerve root:
Guillain-Barré syndrome, herniated disk, or
spinal stenosis
Differentiating between primary and secondary
muscle disorders or neuropathy and myopathy as
revealed by differences in the amplitude, duration,
number, and configurations of the electric activity
Determining whether a muscle abnormality is
caused by drugs (antibiotics, chemotherapy) or
toxins (botulism, snake venom, heavy metals)
Monitoring and evaluating myopathies or
neuropathies21
CONTRAINDICATIONS

Medication regimen that includes anticoagulant
therapy
Infection near or at the sites of electrode placement
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Pelvic Floor
Sphincter Electromyography” section.
Inform the client that the study takes about 1 to 3
hours, depending on the extent of the problem
and the areas to be studied.
Advise the client to avoid cigarette smoking and
caffeine beverages 3 hours before the study.
Inform the client that the sites of needle insertion
are the areas to be studied, usually the muscles of
an extremity.
Administer an ordered analgesic or, if the client is
a child, a sedative.
Obtain a history and assessment of neuromuscular and neurosensory status, diseases or conditions that affect muscle function, level of
muscular function and range of motion, traumatic events, and previous diagnostic tests and
procedures associated with the neuromuscular
system.
THE PROCEDURE

The client is placed on the examination table in a
supine position or on a chair in a sitting position,
depending on the location of the muscles to be
tested. The area or room is protected from noise or
metallic interferences, which can affect test results.
An electrode is applied to the skin to ground the
client. A 24-gauge needle containing a fine wire electrode is inserted into the muscle. The electric potentials of the muscle are amplified, fed into a
loudspeaker, displayed on a screen in waveforms,
and recorded on a magnetic tape all at the same
time. As many as 10 needle electrodes can be

inserted to detect the electricity in the muscle. The
client is forewarned of the pain caused by the needle
insertions. During the test, the muscle activity is
tested at rest, during incremental needle insertion,
and during varying degrees of muscle contraction.
This testing is accomplished by requesting that the
client maintain a relaxed muscle state or perform
progressive muscle contractions while the potentials
are being measured. A muscle in the relaxed state is
usually electrically silent, but fibrillations and fasciculations are detected in a relaxed denervated muscle.
Minimal and maximal contractions reveal single
action or fused patterns of muscle potentials. A
reduction in size or amplitude of the electric waveforms indicates muscle abnormality.22
Nerve conduction studies (electroneurography)
that are conducted in conjunction with EMG are
usually performed before muscle potential testing
(see next section).
NURSING CARE AFTER THE PROCEDURE

Remove the electrodes from the sites and cleanse
the skin.
Assess the sites for hematoma or inflammation,
and administer an ordered analgesic for pain as
needed.
Provide time for the client to rest if needed.
Inflammation at electrode sites: Note and report
pain, swelling, and redness at the insertion sites.
Administer ordered analgesic. Apply warm
compresses.
Hematoma at electrode sites: Note and report
hematoma formation. Administer ordered
medication and treatments. Provide rest, immobilize part, and position for comfort.

ELECTRONEUROGRAPHY
Electroneurography, or nerve conduction study, is
an electrophysiologic study performed to determine
peripheral nerve disease or injury by the measurement of nerve conduction velocity. It is performed
to provide diagnostic information about the location and nature of peripheral nerve abnormalities.
Both motor and sensory nerves can be tested by
using electrodes placed on the skin surface, recording the electric stimuli to a peripheral nerve and the
muscle contraction response, and then analyzing the
time and velocities between the two. Nerve conduction velocities remain normal in the presence of
muscle disease, but conduction velocity is slowed in
diseases that affect peripheral nerves, with the extent
depending on the pathology.
The presence of a muscular disease requires that
conduction studies for peripheral nerve abnormali-

CHAPTER 23—Electrophysiologic

ties be performed after the evaluation of a decreased
velocity that can be caused by the muscle pathology.
This evaluation can be accomplished by determining
the time required for stimulation of the distal end of
the nerve to produce muscle contraction (distal
latency), followed by stimulation of the proximal
part of the nerve. This variable is included in the
calculation of conduction velocity by dividing the
distance in meters by the difference between the
total and distal latency.23
Reference Values
Normal nerve conduction velocity rates; no
peripheral or axial nerve damage or disease
INTERFERING FACTORS

Nerve conduction decreases with age and this
should be considered when test results are
analyzed.
Severe pain can affect test performance.
Inability of client to remain still or to cooperate
during the study.
INDICATIONS FOR ELECTRONEUROGRAPHY

Suspected peripheral nerve degenerative diseases
Evaluation of peripheral neuropathies resulting
from diabetes, as revealed by a reduced conduction velocity rate
Evaluation of nerve damage or transection as in
carpal tunnel syndrome
Suspected damage to peripheral nerves by toxic
substances such as solvents, heavy metals, and
antimicrobials
Differentiation between muscle disease and
peripheral nerve disease revealed by normal as
opposed to reduced conduction velocity
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Electromyography”
section.
Inform the client that, instead of needle electrodes, surface-stimulating electrodes with electropaste are applied and taped to the nerve site
(leg, arm, or face).
Inform the client that an electric current is passed
through the electrode and that a mild sensation is
experienced for the length of time the current is
applied.
THE PROCEDURE

The client is placed on the examination table in a
position that allows exposure of the areas to be stud-

Studies

569

ied. The surface-stimulating electrode is placed over
the nerve to be studied near the placement of the
recording electrode. The electrodes are prepared
with electropaste to ensure proper contact with the
skin. A device produces the shock, and movement of
the stimulating electrode along the nerve assists in
determining the location of nerve damage. The
client is reminded that a shock is felt each time
stimulation is administered. Time is measured from
stimulation to muscle activation or response
between two stimulating sites (distal latency). The
time for the stimulation to travel from the site to
muscle activity (total latency) reveals the velocity of
nerve conduction; this time is recorded in milliseconds (ms). Distances between the stimulation and
recording electrodes are measured in centimeters
(cm). The conduction velocity is calculated by dividing the distance by the difference between total
latency and distal latency and is recorded in meters
per second.24
Results from the studies indicate the presence of
abnormalities based on nerve conduction velocities.
If the velocities remain normal, the weakness is
caused by muscle weakness, although muscle action
potentials during repeated stimulation of a nerve
can reveal disorders of the neuromuscular junction.
If the velocities are slowed, diseases affecting the
peripheral nerves are suspected.25
NURSING CARE AFTER THE PROCEDURE

Aftercare and nursing observations after the study
are the same as those described in the “Electromyography” section.

ELECTROENCEPHALOGRAPHY
Electroencephalography (EEG) is an electrophysiologic study performed to measure the electric activity of the brain cells. It is conducted to assist in
diagnosing and evaluating the course of structural
abnormalities involving the brain. Electrodes are
placed at 8 to 16 sites or at pairs of sites on the scalp
and connected to an amplifier. Recordings of waveforms on a moving paper strip during sleep and
waking periods reveal patterns characteristic of
specific disorders. Guidelines for electrode placement and the use of a uniform lettering and
numbering system to obtain the recordings are standardized for each client and allow comparison of
repeated studies on a single client.26
The study can be performed at the bedside in the
comatose client, although this environment cannot
be controlled in a way necessary to obtain diagnostic
information. Evoked brain potentials can also be
obtained during EEG to measure nerve tract activity

570

SECTION II—Diagnostic

Tests and Procedures

by stimulation of the sensory system (see next
section).
Another study, known as brain mapping, is similar to EEG in procedure. It produces and displays a
color-coded map of computer-analyzed EEG signals
for amplitude and distribution of alpha, beta, theta,
and delta frequencies. It can also map evoked potential responses in determining latency increases and
cognitive function abnormalities. It is undertaken to
specifically locate a problem site in the brain in a
general area of deficit revealed by conventional EEG.
It is useful in obtaining diagnostic information
about headaches, seizure activity, dementia and its
possible causes, and psychiatric abnormalities.27
Reference Values
Normal brain structure and function; electric
activity characteristics with waveforms that
indicate normal EEG signals in frequency and
amplitude
INTERFERING FACTORS

Inability of client to remain still and to refrain
from moving facial muscles, mouth, head, or eyes
during the study
Medications such as sedatives, anticonvulsants,
antiaxolytics, or alcohol
Caffeine-containing beverages or other stimulants
Hypoglycemia or hypothermia
Hair that is dirty, oily, or has had hairspray or
other preparations applied can affect electrode
placement and contact
INDICATIONS FOR ELECTROENCEPHALOGRAPHY

Diagnosis and evaluation of epilepsy and seizure
activity
Suspected intracranial cerebrovascular lesions
such as hemorrhages and infarcts
Suspected intracranial lesions such as tumors
(glioblastoma) or abscesses
Suspected metabolic disorders or inflammatory
process (encephalitis)
Suspected increased intracranial pressure caused
by trauma or disease
Mapping of area of abnormality in dementia,
especially Alzheimer’s disease, or of focal irritation in migraine headaches and psychiatric disorders such as schizophrenia or psychosis
Evaluation of sleep disorders such as apnea and
narcolepsy
Evaluation of the effect of drug intoxication on
the brain
Detection of cerebral ischemia during endarterectomy

Determination of brain death in nonresponsive
clients
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure requires 1 to 2 hours
That a meal should be eaten before the test to
prevent a hypoglycemic state but that caffeinecontaining beverages should be avoided for 8
hours before the test
That some medications are discontinued before
the study but that anticonvulsants should be taken
unless the physician temporarily discontinues
them before the test
That the hair should be shampooed the night
before the test and hair preparations should not
be applied
That sleep time the night before the test should be
limited to 5 hours for an adult and 7 hours for a
child; young children and infants should not be
allowed to nap before the test
That small electrodes are attached to the scalp
with a paste substance and connected to wires
attached to a machine that records the brain waves
That electricity flows from the body and not into
the body during the study
That the test reveals only brain activity—not
thoughts, feelings, or intelligence
That no pain is associated with the study
Prepare for the procedure:
Obtain a history and assessment of the neurological system, known or suspected seizure activity,
intracranial abnormalities, sleep disorders, associated diagnostic laboratory tests and procedures,
and medication regimen.
Ensure that caffeine-containing beverages and
medications have been withheld and that a meal
has been ingested before the study.
Ensure that the client is able to relax. Report any
extreme anxiety or restlessness.
Ensure that the hair is clean and free of hair
sprays, gels, or lotions.
THE PROCEDURE

The client is placed on a bed in a supine position or
on a recliner in a semi-Fowler’s position in a special
room protected from any noise or electric interferences that could affect the tracings. A window in the
room allows the technician to observe the client for
movements or other interference during the study.
The client is reminded to relax and not to move any
muscles or parts of the face or head. The electrodes
are prepared with paste and applied to the scalp to
provide conduction of the electric activity between
the skin and the electrode. Electrodes are small metal

CHAPTER 23—Electrophysiologic

disks connected to the amplifier by wires and positioned on the scalp after standards for placement. As
many as 16 locations over the frontal, temporal,
parietal, and occipital areas of both sides of the head
can be used. Electrodes are attached to each earlobe
as grounders. At this time, a baseline recording can
be made with the client at rest.
As the test begins, recordings are made with the
client at rest with the eyes closed. Recordings are also
made during drowsy and sleep periods, depending
on the client’s clinical condition and symptoms. A
period in which the recording is stopped and movement is allowed during the test is provided about
every 5 minutes. In certain instances, procedures are
undertaken to bring out abnormal patterns: hyperventilation for 3 minutes to produce a state of alkalosis, which could record a seizure pattern or other
abnormalities; stroboscopic light stimulation to
record seizure activity produced by photic stimulation; or sleep induction by administration of a sedative to detect abnormalities that occur only during
sleep through recording of activity while falling
asleep, during sleep, and during waking.
Observations for seizure activity are carried out
during the study and a description and the time of
the activity are noted by the technician. Frequencies
and sites of alpha, beta, delta, and theta waves are
recorded and compared with normal values in
analyzing the EEG results.
Brain mapping or computed tomography is
performed in the same manner as an EEG study
except that 42 electrodes are placed on the scalp and
the study is performed while the client is awake and
at rest. The skin on the scalp is prepared by cleansing
with an Omniprep solution before the electrodes are
attached to the skin with an adhesive paste. The
client is requested to keep the eyes closed and to
remain very still during the complete study. The
color map of the brain’s electric activity is displayed
for analysis. Comparisons are made with normal
reference values for amplitude, and distribution of
the different frequencies is recorded.28
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study include
removing the electrodes and paste from the scalp
and hair with acetone.
Provide a shampoo to remove the substance from
the hair.
Inform the client to resume medications that were
withheld before the study.
Allow clients who received sedatives sufficient
time to rest and provide safety precautions to
prevent injury: side rails for bedridden clients or
assistance with transportation for outpatients.

Studies

571

Perform neurological checks and provide seizure
precautions if the client’s condition is not stable.
Inform the client that normal activity can be
resumed after the rest period.
Seizure activity: Note and report time and observations of seizure. Perform seizure precautions to
prevent injury. Administer anticonvulsive after
the study if it has been withheld.

EVOKED BRAIN POTENTIALS
Evoked brain potentials, also known as cortical
evoked responses, are electrophysiologic studies
performed to measure the electric responses in brain
waves when stimulated by various sensory stimuli or
skin electrodes. They include the visual evoked
response, auditory brainstem evoked response, and
somatosensory evoked response. The stimuli activate the nerve tracts that connect the stimulated area
(receptor area) with the cortical (visual and
somatosensory) or midbrain (auditory) sensory
area. A series of stimuli are given, electronically
displayed in waveforms, and recorded. Abnormalities are determined by a delay in time between the
stimulus and the response, also known as an
increased latency, and measured in milliseconds
(ms). The latency factor used to diagnose these
abnormalities is influenced by client size; area of
stimulation; number of synapses; speed of axons at
the location studied, whether the nerves are located
in the cortex or in the brainstem; and effects of
pathological processes on the central nervous system
(CNS).29 Evoked brain potential studies are
performed to assist in determining structural and
functional abnormalities of organs and providing
diagnostic information about neurological diseases
or surgical procedures that cause changes in the
sensory pathways.
The studies are especially useful in clients with
behavior problems and those unable to speak or
respond to instructions during the test, because their
voluntary cooperation or participation in the activity is not required. This benefit allows objective diagnostic information about visual or auditory
disorders affecting infants and children and differentiation between organic brain and psychological
disorders in adults.
Another study, known as event-related potential,
can be performed using the same methodology
as for the auditory response study to measure
mental function in the presence of neurological
disorders that cause cognitive changes or abnormalities. Abnormalities are revealed by the ability of
cognitive function to process a specific tone (P3),
evidenced by the latency increases resulting from

572

SECTION II—Diagnostic

Tests and Procedures

dementia disorders or decreased mental functioning. Because P3 increases normally with age, the
latency is compared with the normal age-matched
value in evaluating test results for dementia. As
with the other evoked potential studies, this test
has the advantage of objectivity and can be
performed on clients who are unable or unwilling to
cooperate or participate in differentiating between
organic brain disorder and cognitive function
abnormality.30
Reference Values
Normal latency in recorded cortical and brainstem waveforms, depending on age, gender, and
stature; no neurological lesions or sensory disorders associated with the CNS
INTERFERING FACTORS

Inability of client to understand instructions or to
cooperate with requests made during the study
Improper placement of electrodes

Diagnosis of MS and Guillain-Barré syndrome as
revealed by abnormal latencies in the lower limb
studies
Monitoring of sensory potentials to determine
spinal cord function during a surgical procedure
or medical regimen
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Electroencephalography” section.
Inform the client that the electrodes are placed in
specific positions on the scalp and stimuli are
provided, depending on which study is being
performed.
Inform the client that there are no food, fluid, or
medication restrictions and that the study takes
about 30 minutes.
Obtain a history that includes known and
suspected neurological conditions, changes in
sensory perception, and traumatic incidents to
the head or spinal cord.

INDICATIONS FOR EVOKED BRAIN POTENTIALS

THE PROCEDURE

Visual Evoked Potentials
Diagnosis of neurological disorders such as
Parkinson’s disease, Huntington’s chorea, and
multiple sclerosis (MS) as revealed by abnormal
bilateral latency resulting from the demyelination
of nerve fibers
Diagnosis of cryptic or past retrobulbar neuritis
revealed by abnormal latency or lengthened
conduction time along optic pathways
Determination of optic pathway lesions and
visual cortex defects revealed by abnormal latency
Diagnosis of lesions of the eye or optic nerves
revealed by an extended latency
Evaluation of binocularity in infants

Visual Evoked Potentials. The client is placed in a
comfortable position at a specific distance from the
stimulation source. The electrodes are attached to
the occipital and vertex lobes, and a reference electrode is attached to the ear. A light-emitting stimulation or a checkerboard pattern is projected on a
screen at a regulated speed. This procedure is
performed for each eye as the client is requested to
look at a dot on the screen with one eye covered
while the stimuli are delivered. A computer interprets the brain’s responses to the stimuli and records
them in waveforms.

Auditory Evoked Potentials
Detection of abnormalities or lesions in the brainstem or auditory nerves that cannot be diagnosed
by other diagnostic methods
Suspected hearing loss (peripheral) and screening
or evaluation of low-birth-weight neonates,
infants, children, and adults for auditory problems
Early detection of brainstem tumors and acoustic
neuromas, revealed by abnormal latency
responses
Somatosensory Evoked Potentials
Evaluation of spinal cord and brain injury and
function
Diagnosis of sensorimotor neuropathies and
cervical pathology revealed by abnormal latencies
in the upper limb studies

Auditory Evoked Potentials. The client is placed in
a comfortable position and the electrodes are positioned on the scalp at the vertex lobe and on each
earlobe. Earphones are placed in the client’s ears,
and a clicking stimulus is delivered into one ear
while a continuous tone is delivered to the opposite
ear. The response to the stimuli is recorded as waveforms for analysis.
Somatosensory Evoked Potentials. The client is
placed in a comfortable position and the electrodes
are positioned at the nerve sites of the wrist, knee,
and ankle and on the scalp at the sensory cortex of
the hemisphere on the opposite side (the electrode
that picks up the response and delivers it to the
recorder). Additional electrodes can be positioned at
the cervical or lumbar vertebrae for upper or lower
limb stimulation. The rate at which the electric
shock stimulus is delivered to the nerve electrodes
and travels to the brain is measured, interpreted by a

CHAPTER 23—Electrophysiologic

computer, and recorded in waveforms for analysis.
Both sides can be tested by switching the electrodes
and repeating the procedure.31
NURSING CARE AFTER THE PROCEDURE

Aftercare and nursing observations after the study
include removing the electrodes and paste and
cleansing the scalp, hair, and skin sites.

ELECTRONYSTAGMOGRAPHY
Electronystagmography (ENG) is an electrophysiologic study performed to measure the direction and
degree of nystagmus. Nystagmus is the involuntary
back-and-forth eye movement resulting from initiation of the vestibulo-ocular reflex, which maintains
visual fixation when the head’s position is changed.
The vestibular system also maintains body balance
through postural reflexes. This study evaluates the
vestibulo-ocular reflex, which is the relationship
between the vestibular system and the muscles that
control eye movements. It is performed by measurement of electric responses of and around the eye at
rest and to various stimuli applied to the eye to elicit
nystagmus: positioning, caloric stimulation, gaze
change, and pendulum movement.32
The duration and velocity of the eye movements
recorded are compared with normal values, with
prolonged nystagmus indicating an abnormality in
the vestibular or ocular system. Abnormalities of the
vestibular system are characterized by vertigo and
manifestations such as nausea, vomiting, and perspiration. Tinnitus and hearing impairment can also
result from abnormal nystagmus. Nystagmus that is
controlled by the vestibular system is known as the
slow phase, in which the eyes move in opposite
directions to maintain a fixation point in the visual
field. Nystagmus that is controlled by the CNS is
known as the fast phase, in which an eye correction
takes place to obtain a new fixation point (saccadic
return) if the head is rotated beyond the range of
lateral eye movement. The described slow–fast
phases of nystagmus are the result of sensory organ
or vestibular nerve function. Nystagmus that
involves equal rates in the direction of eye movements (vertical, horizontal, rotary, mixed) is the
result of CNS pathology.33

Reference Values
Normal nystagmic response during the turning
of the head and normal vestibulo-ocular reflex;
no hearing loss or lesions of the ocular or
vestibular systems

Studies

573

INTERFERING FACTORS

Inability of client to understand or to cooperate
by refraining from blinking the eyes
Improper placement of electrodes around the eyes
Visual impairment that prevents the ability to
cooperate
Medications such as sedatives, stimulants,
depressants, and antivertiginics, which can
prevent the client from cooperating in the test,
suppress nystagmus, or produce other eye movements
INDICATIONS FOR ELECTRONYSTAGMOGRAPHY

Dizziness, vertigo, or tinnitus
Suspected lesions of the CNS (brainstem and
cerebellum)
Location of an abnormality: tumors, cerebral
brain damage, circulatory disorders, or demyelinating diseases34
Suspected lesions of the peripheral system (end
organ or vestibular branch of the eighth cranial
nerve): tumors, middle ear infection, ototoxicity
from drugs, food allergies, head trauma, balance
instability, Ménière’s disease, or changes caused by
advancing age
Differentiation between nystagmus caused by
the peripheral nervous system and that caused by
the CNS
Diagnosis of congenital disorders in infants
Determination of cause of hearing loss
CONTRAINDICATIONS

Perforated eardrum if water calorics test is to be
performed, unless the test is modified by placing a
fingercot in the canal
Presence of a pacemaker because the test can
interfere with its function
Disorders of the neck that prevent position
changes of the head during the tests
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Electroencephalography” section.
Inform the client that electrodes are placed on the
face around the eye.
Inform the client that the study takes about 1
hour; instruct the client to avoid applying makeup
to the face, to eat a light meal before the study, and
to avoid smoking and caffeine-containing beverages for 48 hours before the study.
Instruct the client to withhold stimulants, depressants, or antivertiginous drugs for 5 days before
the study.

574

SECTION II—Diagnostic

Tests and Procedures

Assess ear canals to determine the presence of wax
in the ears; obtain a history and assessment of the
neurological system for symptoms such as tinnitus, hearing loss, vertigo, dizziness, or ear pain or
drainage; obtain a history of the medication regimen, diagnostic laboratory tests, and procedures.
THE PROCEDURE

The client is placed on the examination table in a
supine or seated position in a darkened room. The
client is informed that some discomfort is associated
with some of the tests and that someone will be in
attendance to assist if dizziness or other symptoms
such as nausea and vomiting occur. Cerumen in the
ears is removed, and the skin at the electrode sites is
cleansed and dried. The five electrodes, prepared
with paste to ensure proper conduction, are positioned at the outer canthus of each eye to test horizontal nystagmus, above and below the eye center
for vertical nystagmus, and, at the center of the forehead, a ground electrode is placed. The electrodes
pick up the potentials as the eyes move in a horizontal or vertical direction and a recorder amplifies the
signals and charts them with a pen writer.35 The
client is reminded that instructions will be given for
activities and position changes to be performed
during the test. Several tests can be performed to
examine the nystagmic response to the different
procedures:
Gaze nystagmus: Request the client to close the
eyes. Spontaneous eye movements are recorded
while the client concentrates on a mental task.
Center gaze is recorded by having eyes fix on a
center light; right gaze, by moving the eyes to the
right; and left gaze, by moving the eyes to the left.
A recording is made with eyes closed after each
directional change, with timing of each gaze
change and closed-eyes period.
Pendulum tracking: Request that the client
follow a pendulum or light. Body and eye movements are recorded.
Positional changes: Request that the client
change the head position as follows: eyes looking
straight ahead and closed, head turning to the
right and then to the center, head turning to the
left and then to the center, lying to sitting position, sitting to lying position, lying in supine to
both right and left side-lying position, head hanging over the edge from lying to sitting and after
sitting position, and head hanging over the edge
to the right and left positions.
Water caloric: While the client is in a supine position with the head elevated to a semi-Fowler’s
position, water of a specific temperature is
instilled into the ear canals for 30 seconds. The
irrigation return is collected in a basin placed

under the ear. Recordings are made during the
study as the client is requested to perform mental
tasks, open and fix the eyes on an object, and then
close the eyes. Stimulation by different water
temperatures is performed, cold water in some
instances, and the response is recorded; air of
different temperatures as an alternative to water
can be introduced into each ear to obtain the
same information.36
The results of these tests are recorded on charts
and portions are analyzed for abnormalities by
comparing them with the established values. They
are noted as normal, borderline, or abnormal.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study include
removal of the electrodes and cleansing of the
skin.
Allow a period of rest and assess for complaints of
nausea, dizziness, or fatigue.
Instruct the client to remain at rest for as long as
weakness or dizziness is present.
Nausea and dizziness: Note and report symptoms if they persist. Provide bed rest. Resume
ordered medication regimen. Assist with transportation home, if it is needed.

ELECTRORETINOGRAPHY
Electroretinography (ERG) is an electrophysiologic
study performed to measure the electric activity of
the retina in response to a flash of light stimulus.
Electrodes are placed in a corneal contact lens and
on the forehead of the client, and electric activity
changes are recorded and displayed on a screen for
viewing and analysis. The study allows diagnostic
information in evaluation of retinal function and
viability in those with opaque lens, corneal opacity,
or vitreous body.
The retina is the inner layer of the posterior twothirds of the eyeball; it contains the neural receptors
for vision. It is at this portion of the eye that light is
converted to activity potentials and transmitted to
visual centers in the brain via its connection to the
optic nerve. Two types of photoreceptors are present: rods, which discriminate black and white, and
cones, which discriminate color. Light energy causes
nerve excitation, allowing the test to assist in diagnosing congenital and acquired retinal diseases and
retinal blood vessel abnormalities.
Reference Values
Normal electric responses to light (alpha and
beta waveforms); no acquired or inherited retinal conditions

CHAPTER 23—Electrophysiologic

INTERFERING FACTORS

Inability of client to remain still during the procedure
Improper placement of the electrode on the
cornea
INDICATIONS FOR ELECTRORETINOGRAPHY

Suspected retinal detachment or degeneration in
the presence of opacities of the ocular contents or
parts
Suspected retinal damage caused by drugs as
revealed by decreased response
Evaluation of color blindness and night blindness
revealed by a reduced response
Suspected congenital disorders such as mucopolysaccharidosis revealed by the effect on the lens of
the cornea, causing a reduced response
Diagnosis of retinitis pigmentosa when performed with electro-oculography
Detection of retinopathy or vascular ischemia and
other blood vessel abnormalities resulting from
diabetes, atherosclerosis, and aging changes,
revealed by a reduced response37
Evaluation of retinal status before surgery or
other treatment such as laser
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Electronystagmography” section.
Administer ordered eyedrops to anesthetize the
eye and a sedative if the client is a child.
Prepare a child or infant for general anesthesia if
it is to be administered.
Inform the client that a light is used to perform
the test and that little or no discomfort is experienced during the procedure.
Obtain a history of known or suspected congenital or acquired eye disorders or diseases that
predispose to eye abnormalities, signs and symptoms of eye condition, and previous associated
diagnostic tests and procedures.
THE PROCEDURE

The client is placed on the examination table in a
supine position or on a chair in a sitting position in
a room that allows light adjustments. The eyes are
anesthetized and then propped open with a retractor. Electrodes saturated with saline are placed on
the cornea to receive the light stimuli that record and
display electric changes on a screen. A recording is
made in ordinary room light, in a dark room with a
flash of white light delivered after the eye has had a
chance to accommodate to the dark, and a flash of a
very bright light if vitreous opacity is present.38
Normal values are established, depending on the

Studies

575

intensity of the wavelengths of light, which determine the expected electric response (usually
increased in proportion to the intensity).
NURSING CARE AFTER THE PROCEDURE

Assess the eyes for irritation after the removal of
the electrodes.
Inform the client that the anesthetic dissipates in
about 20 minutes but that the eyes should not be
rubbed or touched for at least 1 hour to prevent
any injury.
Allow time for the client to rest if needed.
Corneal abrasion: Note and report eye pain or
visual impairment complaints. Restrain or
instruct the client to refrain from rubbing or
touching the eyes after the procedure. Administer
eye medications as ordered and apply sterile eye
pad dressing.

ELECTRO-OCULOGRAPHY
Electro-oculography (EOG) is an electrophysiologic
study performed to measure electric potentials
between the front of the eye and the retina in the
back of the eye. The study determines changes in the
potentials in dark and light environments with the
eye at rest. Abnormalities are based on increases in
electric potentials in relation to increased light.
Electrodes are placed in specific areas of the canthi
and the electric potentials are recorded on a graph
for viewing and analysis.39 The EOG study can be
followed by fluorescein angiography (see Chapter
18) to diagnose vascular disorders of the retina or in
conjunction with ERG (see preceding section) to
diagnose congenital disorders of the retina.
Reference Values
Normal retinal function with an electric potential
of 1.80 to 2, depending on testing methods used;
no inherited or acquired retinal pathology
INTERFERING FACTORS

Inability to understand or to cooperate in instructions for eye movement during the procedure
Improper placement of the electrodes around the
eyes
INDICATIONS FOR ELECTRO-OCULOGRAPHY

Evaluation of retinal functional status in retinitis
pigmentosa (degeneration of the outer pigmented
layer) when performed in conjunction with ERG
as revealed by a decrease in the electric potential
Suspected retinopathy caused by antimalarial or
other toxic drugs, revealed by abnormally reduced
potentials

576

SECTION II—Diagnostic

Tests and Procedures

Evaluation of retinal damage in albinism or irideremia revealed by an abnormal increase in
potentials
Diagnosis of congenital macular degeneration in
the younger population as revealed by abnormal
decrease in electric potentials40
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Electronystagmography” section.
Obtain a history of known or suspected congenital or acquired eye disorders or diseases that
predispose to eye abnormalities, signs and symptoms of an eye condition, and previous eye diagnostic tests and procedures.
Determine whether ERG or fluorescein angiography is to be performed on the same day, the
proper succession of the tests, and the waiting
periods between them.
THE PROCEDURE

The client is placed on a chair in a sitting position.
The electrodes are applied to the skin at the inner
and outer canthi sites of the eye. The electrodes
receive the stimulus, and the responses are recorded
on a chart. The first recording is made of measurements of electric potentials of the eye at rest and
during specific movements in a dark room. Then a
light stimulus is provided and measurements of the
eye potentials are recorded at rest and during the
same movements as in the first recording. The
normal recordings should reflect an increase in
potentials between the front and back of the eye
when light is applied, with increases proportional to
increases in the light stimulus.41
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study include
assessment of the eyes and removal of the electrodes and cleansing of the skin sites.
Help clients with impaired vision to return home

or to their room in the hospital. Allow the client to
rest and proceed with teaching and physical
preparation if another procedure is to follow, such
as fluorescein angiography.
REFERENCES
1. Thomas, CL (ed): Taber’s Cyclopedic Medical Dictionary, ed 18. FA
Davis, Philadelphia, 1997, p 617.
2. Fischbach, FT: A Manual of Laboratory Diagnostic Tests, ed 4. JB
Lippincott, Philadelphia, 1992, pp 884–885.
3. Pagana, KD, and Pagana, TJ: Mosby’s Diagnostic and Laboratory
Test Reference. Mosby–Year Book, St Louis, 1992, p 285.
4. Ibid, pp 284–285.
5. Corbett, JV: Laboratory Tests and Diagnostic Procedures with
Nursing Diagnoses, ed 3. Appleton & Lange, Norwalk, Conn, 1992,
p 594.
6. Fischbach, op cit, p 886.
7. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 895.
8. Pagana and Pagana, op cit, pp 286–287.
9. Corbett, op cit, p 590.
10. Nurse’s Reference Library, op cit, p 895.
11. Fischbach, op cit, p 892.
12. Ibid, p 893.
13. Ibid, p 894.
14. Pagana and Pagana, op cit, p 333.
15. Ibid, p 334.
16. Fischbach, op cit, pp 889–890.
17. Ibid, p 890.
18. Porth, CM: Pathophysiology: Concepts of Altered Health States, ed
5, JB Lippincott, Philadelphia, 1998, p 686.
19. Pagana and Pagana, op cit, p 548.
20. Berkow, R: The Merck Manual, ed 16. Merck Sharp and Dohme
Research Laboratory, Rahway, NJ, 1992, p 1392.
21. Ibid, p 1392.
22. Fischbach, op cit, p 872.
23. Pagana and Pagana, op cit, pp 295–296.
24. Nurse’s Reference Library, op cit, p 774.
25. Berkow, op cit, p 1392.
26. Ibid, p 1391.
27. Fischbach, op cit, p 869.
28. Ibid, p 869.
29. Pagana and Pagana, op cit, p 330.
30. Fischbach, op cit, p 868.
31. Nurse’s Reference Library, op cit, p 757.
32. Ibid, p 614.
33. Porth, op cit, p 1015.
34. Berkow, op cit, p 2325.
35. Nurse’s Reference Library, op cit, p 617.
36. Ibid, pp. 617–619, 624.
37. Porth, op cit, p 795.
38. Fischbach, op cit, pp 877–878.
39. Ibid, p 875.
40. Ibid, p 876.
41. Ibid, p 876.

CHAPTER

Studies of Specific
Organs or Systems
TESTS COVERED
Cardiac Catheterization Study, 578
Pulmonary Artery Catheterization Study,
582
His Bundle Evoked Potential Study, 583
Cold Stimulation Test, 585
Pulmonary Function Study, 586
Exercise Pulmonary Function Study, 590
Oximetry, 591
Sweat Test, 592
Spinal Nerve Root Thermography, 594
Tensilon Test, 595
Hearing Loss Audiometry, 596
Hearing Loss Tuning Fork Tests, 598

Acoustic Admittance Tests, 599
Otoneurological Tests, 601
Otoneural Lesion Site Tests, 603
Spondee Speech Reception Threshold
Test, 604
Visual Acuity Tests, 605
Visual Field Tests, 607
Color Perception Tests, 608
Tonometry, 609
Refraction, 610
Slit-Lamp Biomicroscopy, 611
Schirmer Tearing Test, 612
Corneal Staining Test, 613

INTRODUCTION

This chapter provides information about invasive and noninvasive diagnostic tests related to organs or body systems. These tests can be performed to determine
abnormal patterns and functions, deficits, or pathology of a particular organ or system. The
tests or studies of the cardiovascular, pulmonary, and neurological systems that have been
placed in this chapter fail to meet the criteria for inclusion in other chapters of this book. Note
that some of the tests or studies in this chapter contain more than one procedure that can be
used to obtain different types of information about an organ system or to differentiate between
the types of pathology affecting an organ.

CARDIOVASCULAR SYSTEM
Cardiovascular system studies include procedures to
obtain diagnostic information about the heart’s
chambers, coronary artery patency, and conduction
disturbances and to correctly place catheters to
measure pulmonary artery pressures. These studies
are performed to support and extend information

obtained by other procedures such as echocardiography, radiography, and radionuclide computerized
scanning in diagnosing and evaluating the heart and
the coronary and great vessels. Also included in this
section is the test performed to determine peripheral vascular alterations associated with Raynaud’s
syndrome.
Cardiovascular procedures are performed by a
577

578

SECTION II—Diagnostic

Tests and Procedures

Figure 24–1. Insertion sites and routes of left and right side heart catheterization.

cardiologist in a special cardiac laboratory room,
except for pulmonary artery catheter monitoring,
which can be performed at the bedside as well. Local
anesthesia and strict sterile technique are used for
cardiovascular procedures. A signed informed
consent is required unless otherwise specified.

CARDIAC CATHETERIZATION STUDY
Cardiac catheterization is an invasive study that
provides diagnostic information about the heart
chambers and valves, coronary arteries, and the great
vessels. In general, it is usually reserved for use when
noninvasive procedures have not provided a definitive diagnosis, when more exact knowledge of the
extent and severity of a heart condition is needed, or
when the medical regimen is no longer effective and
surgical intervention is advised. The study is
performed by the insertion and passage of a flexible
catheter into the heart chambers, the pulmonary
artery, and the coronary vessels under the guidance
of fluoroscopy. Catheter insertion is followed by the
injection of a dye or contrast medium into the heart
chambers or great vessels, which allows instant visualization and filming of heart activity or measurement of pulmonary artery pressures (angiography).
Injection into the coronary arteries allows visualization and filming of vessel abnormalities (coronary
arteriography). A right or left heart catheterization,
or both, with different types of tests can be
performed during the procedure, based on a client’s
history and signs and symptoms.
Left heart catheterization to obtain information
about the left side of the circulation involves the
retrograde insertion of the catheter via a cutdown in
the right brachial artery, via a percutaneous puncture of the right femoral artery (most common site),
or via a transseptal technique. The catheter is

advanced into the aorta and left heart or into the
coronary arteries in the retrograde technique (Fig.
24–1). It is advanced into the right atrium and
right septum, then into the left atrium and across
the mitral valve into the left ventricle in the
transseptal technique. The transseptal technique is
used when aortic valve stenosis prevents passage of
the catheter into the left side of the heart via the
retrograde technique.1 This technique permits
examination of left heart activity and, after the
injection of a contrast medium, evaluation of aortic
and mitral valve abnormalities and patency of
coronary arteries. Left heart catheterization and
coronary artery cannulation with a special balloon
catheter can be performed by forcefully inflating
the balloon to dilate specific stenotic or obstructed
areas in the coronary vessels. This is known as
percutaneous transluminal coronary angioplasty
(PTCA).
Right heart catheterization to obtain information
about the right side of the circulation involves the
insertion of the catheter via a cutdown in the antecubital vein or via a puncture of the femoral vein.
The catheter is advanced into the inferior vena
cava, the right atrium, and then the right ventricle,
across the pulmonary valve, and into the pulmonary
arteries (see Fig. 24–1). This procedure permits
examination of the right heart activity and measures
the pressures of the right atrium, ventricle, and
pulmonary artery as the catheter is advanced
through these parts of the heart. Pulmonary artery
pressure (PAP) and pulmonary artery wedge pressure (PAWP) are also measured during this procedure, because these measurements reflect changes
that occur in left atrium pressure. Blood samples for
blood gases can be obtained, primarily oxygen
content of blood at different levels within the heart
and great vessels, to evaluate the shunting of blood

CHAPTER 24—Studies

and its characteristics within the heart. The function
of the tricuspid and pulmonary valves can be evaluated after the injection of a contrast medium in right
heart catheterization.2
Cardiac output and related blood volume studies
can be calculated from findings obtained from
cardiac catheterization. Cardiac output is the
volume of blood ejected by the heart in 1 minute. It
can be calculated by the Fick technique, by which the
oxygen content of expired air is measured and
subtracted from the oxygen content of room air. The
difference is divided by the arteriovenous oxygen
difference obtained from both arterial and venous
blood samples. Another technique is the dye dilution
technique, usually performed in association with
cardiac catheterization. This technique involves the
injection of a predetermined amount of indocyanine green or Evans blue dye into the venous system
while arterial blood is withdrawn, with the concentration of the dye measured and recorded as a curve.
Cardiac output is calculated from the curve using
the appearance time, the buildup time, and the
disappearance time segments. Both methods are
based on the total uptake or release of a substance by
an organ, depending on blood flow to the organ and
the artery and on venous concentration differences
of a substance.3
Equipment that provides visualization includes
an image intensifier, a television system, and an
instant replay recording of the fluoroscopic images.
Special equipment for measurement of pressures of
the heart and vessels and other procedures and
emergency events is available in a catheterization
laboratory to accommodate this study.

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579

INTERFERING FACTORS

Anxiety level can affect cardiac rate, which affects
pressures in the chambers.
Inability of client to remain still or to understand
the need to cooperate during the study.
Improper placement of the catheter or other failures in technique.
INDICATIONS FOR CARDIAC
CATHETERIZATION STUDY

Diagnosis and determination of the severity of
cardiac and great vessel diseases when other
noninvasive studies have not produced a definitive diagnosis
Chest pain in clients at risk for heart disease or in
those with known angina or abnormal electrocardiography (ECG)
Determination and location of partial or
complete coronary artery occlusion in the diagnosis of CAD or confirmation of the need for cardiac
bypass surgery revealed by narrowing of the
lumen of coronary arteries and lack of coronary
perfusion
Diagnosis of acquired and congenital valvular
disease (stenosis, insufficiency, regurgitation)
and determination of the severity as revealed
by abnormal pressures and blood flow at the
valve site
Confirmation or evaluation of acquired and
congenital atrial and ventricular septal defects or
shunting of blood, extent of the abnormality, and
direction and volume of the shunting, as revealed
by abnormal blood oxygen content at different

Reference Values
Normal heart chambers and great vessel size, structure, function, direction of blood flow, and
valves; normal pressures of heart chambers and pulmonary artery, cardiac output, ejection fraction, blood volume and oxygenation, and patency of the cardiac vascular system
Pressures
Left ventricular systolic

90–140 mm Hg

Left ventricular end-diastolic

4–12 mm Hg

Central venous pressure

2–14 cm H2O

Left atrium

2–12 mm Hg

Pulmonary artery systolic/end-diastolic

17–32/4–13 mm Hg

Pulmonary wedge pressure

6–13 mm Hg

Cardiac Output

3–6 L/min

Ejection Fraction

60–70%

Note: No coronary artery disease (CAD), congenital or acquired anatomic abnormalities or septal defects, valvular
abnormalities, aneurysm, pulmonary embolism, or hypertension.

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SECTION II—Diagnostic

Tests and Procedures

levels of the right and left sides of the heart and
great vessels
Determination of the presence and severity of
congenital cardiac abnormalities in infants, that
is, patent ductus arteriosus, transposition of the
great vessels, and need for corrective surgery
Determination of left ventricular hypertrophy or
ventricular aneurysm as revealed by abnormal
chamber size, cardiac muscle or wall motion, and
ejection fraction
Diagnosis and determination of the extent of
aortic atherosclerosis or aneurysm as revealed by
abnormal pressure in the aortic artery
Diagnosis of pulmonary venous return abnormalities and determination of the presence of
pulmonary hypertension or embolism
Monitoring of PAP, PAWP, and blood volumes
after insertion of a Swan-Ganz catheter in acutely
ill clients
Acute myocardial infarction to infuse a thrombolytic medication into the occluded coronary
arteries to relieve obstruction caused by blood clot
Performance of PTCA to relieve occluded or
stenotic coronary arteries
Evaluation of the success of cardiac surgery or
PTCA procedures, as revealed by improved blood
flow to the myocardium
Measuring of cardiac output and calculating ejection fraction based on end-diastolic and systolic
volumes and stroke volume findings in cardiac
monitoring of acutely ill clients
Obtaining of blood samples from the chambers or
by the dye dilution technique for oxygen content
and saturation analysis in determining cardiac
abnormalities, especially cardiac output
CONTRAINDICATIONS

Allergy to the contrast medium used in the
angiography portion of the study
Pregnancy, unless the benefits of performing the
study greatly outweigh the risks to the fetus
Clients who will not allow cardiac surgery to be
performed to correct pathology diagnosed by the
study
Medical conditions such as severe infection, irreversible brain damage, or congestive heart failure
(CHF), which are considered relative to their
extent, emergency status, and potential benefit as
opposed to the risk
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure is performed in a special
cardiac laboratory equipped with monitors and
supplies to minimize the risk of complications

Nursing Alert

The following equipment and associated
supplies should be on hand when performing
cardiac catheterization to treat ventricular
arrhythmias or other complications: resuscitation bag; oxygen; suction; oximetric device;
endotracheal tube; airway; defibrillator; monitor for pulse and blood pressure; ECG; external temporary pacemaker; and medications
such as lidocaine (Xylocaine), bretylium
(Bretylol), epinephrine (Adrenalin), atropine,
morphine, and isoproterenol (Isuprel).

That the procedure is performed by a physician
(cardiologist) and takes about 1 to 3 hours,
depending on the tests to be performed
That food and fluids are withheld for at least 4 to
6 hours before the study
That some routine medications are withheld
according to physician instruction, especially
anticoagulant therapy, which is discontinued
before the study
That the site is shaved, cleansed, and anesthetized
with a local anesthetic, that the catheter is inserted
into a vein or artery as appropriate for the tests to
be performed, and that children are given general
anesthesia for this procedure
That a feeling of pressure is experienced as the
catheter is inserted and that a sensation is experienced as the catheter is advanced
That a sedative, analgesic, or other medication to
allay anxiety and promote comfort is given 1 hour
before the study
That ECG activity, pulse, and blood pressure
are monitored during the procedure because a
temporary increase in pulse or arrhythmia can
occur during the advancement of the catheter
That a contrast medium can be injected into the
heart and vessels and cause a warm feeling or
metallic taste but that it lasts only a few minutes
That the client can be requested to cough or
breathe deeply during the study to enhance the
blood flow through the heart
Prepare for the procedure:
Obtain the client’s height and weight, which will
be used to determine dye administration.
Ensure that dietary and fluid restrictions have
been followed.
Ensure that routine medications are restricted or
allowed per physician order and that anticoagulants have been discontinued.
Provide a hospital gown without metallic
closures. Allow the client to retain dentures,

CHAPTER 24—Studies

glasses, or hearing aids, because they do not interfere with the study.
Ensure that medications to reduce allergic
response to the contrast medium are administered, that is, antihistamine or corticosteroid.
Obtain baseline pulse, blood pressure, ECG, and
peripheral pulses, and mark the sites of peripheral
pulses for comparison after the study.
Administer a sedative or antianxiety agent such as
diazepam (Valium), or both types of medication,
and an analgesic such as meperidine (Demerol) as
ordered before the procedure (30 minutes to 1
hour).
Initiate an intravenous (IV) line to administer
fluids and medications as needed during the
procedure.
Have the client void before the procedure.
Obtain a history of suspected or known cardiac
conditions, cardiovascular status, cardiac medications, allergies to iodine, and previous tests and
procedures.
THE PROCEDURE

The client is placed in a supine position on the
examining table. Straps secure the client in place on
the table in the event of tilting. An IV infusion of
D5W is initiated to keep the vein open for medication administration. ECG leads are positioned and
attached to the client. Blood pressure, pulse, and
respiration equipment are used for continuous
monitoring of heart activity and vital signs. The
catheterization site is shaved if necessary, cleansed,
and draped to establish a sterile field. All aspects of
the study are carried out using sterile technique. A
local anesthetic is injected at the insertion or
cutdown site, and general anesthesia via gas or rectal
suppository is administered to young children. The
site selected depends on whether the right or left side
of the heart is to be catheterized, that is, femoral or
antecubital vein for the right side and brachial or
femoral artery for the left side. The vein or artery is
punctured with a needle and a wire inserted through
the needle. The catheter is then passed over the wire
and into the vessel after the needle is removed.
Guided by fluoroscopy in a darkened room, the
physician advances the wire and catheter into the
right atrium, through the tricuspid valve, into the
right ventricle, through the pulmonary valve, and
into the pulmonary arteries for right side catheterization and into the aorta, through the aortic valve,
and into the left ventricle or coronary arteries for left
side catheterization.4 Cardiac pressures, volume
readings, and blood gas levels are obtained. The
contrast medium is injected into the chamber to
visualize heart size and activity, aneurysms or steno-

of Specific Organs or Systems

581

sis, and ventricular abnormalities and into each
coronary artery to determine patency. X-ray films
are taken in rapid sequence at all angles as the
client’s position is changed. The client can be
requested to cough or perform exercises during the
study to measure heart activity during stress.
The catheter is removed with one smooth movement after the completion of the study. The site is
sutured if a cutdown was performed, and a sterile
pressure dressing is applied.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study include monitoring vital signs every 15 minutes for 1 hour,
every 30 minutes for the next hour, and every
hour if stable, taking peripheral pulses and assessing skin for color and temperature on both
extremities of the site and comparing for circulatory alterations.
Maintain bed rest for 6 to 8 hours, depending on
the procedure (for femoral artery puncture; less if
the right heart was catheterized via the femoral
vein).
Extend the extremity used and immobilize it with
sandbags.
Encourage movement of the unaffected extremities.
Resume food, fluids, and medications, and
encourage additional fluids to offset the diuretic
effect of the contrast medium.
Schedule postprocedure ECG and future suture
removal from the insertion site.
Reaction to iodinated contrast medium: Note
and report pruritus, urticaria, rash, breathing
changes, or pulse changes. Administer antihistamines and corticosteroids. Have resuscitation
equipment and supplies on hand.
Thrombophlebitis/infection/bleeding at site:
Note and report excessive bleeding, hematoma
formation, pain, skin color, swelling, or drainage
at site. Administer ordered antibiotics, monitor
vital signs and peripheral pulses, and apply ice or
warm compresses to the site as appropriate.
Arrhythmias: Note and report ventricular cardiac
rhythm abnormalities on the ECG strip. Monitor
vital signs. Administer ordered antiarrhythmics,
oxygen, or other treatments.
Cardiac tamponade: Note and report reduced
cardiac output and associated anxiety, tachypnea,
distended neck veins, narrowing pulse pressure,
muffled heart sounds, paradoxic pulse, or changes
in vital signs. Have resuscitation equipment and
supplies and pericardiocentesis supplies on hand.
Systemic or pulmonary emboli: Note and report
dyspnea, tachypnea, chest pain, or increase in

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Tests and Procedures

pulse rate. Position the client in a sitting or highFowler’s position. Administer oxygen and monitor vital signs.

PULMONARY ARTERY
CATHETERIZATION STUDY
Pulmonary artery catheterization is an invasive
study that provides information about the pumping
ability of the heart by measurement of the PAP and
the PAWP, or pulmonary capillary wedge pressure. It
is performed in acutely ill clients to monitor left
atrial and ventricular end-diastolic pressure and
other hemodynamic parameters, that is, central
venous pressure (CVP) and cardiac output.
Measurement is achieved by obtaining readings of
the pulmonary capillary pressures in the pulmonary
artery because they are the same as pressures in the
left side of the heart during diastole. A multiluminal,
flow-directed, balloon-tipped Swan-Ganz catheter is
inserted into a peripheral vein (cephalic, subclavian,
femoral) and advanced into a position in the
pulmonary artery that allows pressure readings. The
catheters are available in two, three, or four lumens
of varying lengths. A balloon lumen is used for the
inflation of air to measure PAWP and to advance the
catheter into the desired position; a distal lumen is
used to measure PAP and PAWP and to obtain blood
samples; a proximal lumen is used to measure right
atrial or CVP and to inject ice water for cardiac
output determination; and a fourth lumen is
equipped with a thermistor probe to measure
cardiac output by thermodilution after the injection
of ice water.5
Reference Values
Normal PAP and PAWP
Pressures
PAP

20 mm Hg

PAWP

6–12 mm Hg6

INTERFERING FACTORS

Improper placement or position of the catheter.
Mechanical ventilation equipment can alter pressure readings as the intrathoracic pressure is
increased. Improper functioning or problems
with the monitoring or recording equipment,
such as air or clot in system, waveform or transducer damage or dampness, balloon overinflation
or rupture, leaks resulting from loose connections, or incorrect position of stopcock or monitor calibration.

INDICATIONS FOR PULMONARY ARTERY
ATHETERIZATION STUDY

Monitoring acutely ill clients with sudden respiratory failure or failure of two or more organ
systems
Determining right or left ventricular impairment,
defects, or failure as revealed by abnormal PAP
and PAWP readings
Determining pulmonary hypertension, pulmonary diseases, or pulmonary edema or embolus as
revealed by increased PAP and PAWP
Determining atrial or ventricular septal defects
causing shunting of blood and increased pulmonary blood flow as revealed by high PAP
Determining pulmonary vascular resistance and
ventricular stroke work to diagnose cardiac function abnormalities
Diagnosing pericardial involvement affecting
cardiac function, that is, effusion, tamponade, or
pericarditis, as revealed by increased right atrial
and ventricular pressures
Determining oxygen delivery to tissues by measurement of arterial oxygen content and thermodilution flow, especially if mechanical ventilation is
used, because mechanical ventilation can depress
cardiac output
Evaluating the composition of mixed venous
blood (oxygen tension) obtained from the
pulmonary artery to assist in determining a prognosis (Decreases indicate a poor prognosis.)
Measuring cardiac output via thermodilution in
the evaluation of myocardial contractility after a
myocardial infarction or in the presence of fluid
losses
Evaluating or monitoring cardiac, pulmonary,
and fluid status after cardiac surgery
Evaluating the effects of inotropic drugs, respiratory therapy, and fluid infusion status
Nursing Alert

Troubleshooting interventions to solve potential problems associated with pulmonary
artery catheters and monitoring equipment
should be carried out in a systematic manner
to ensure accurate readings by experienced
personnel, and agency policy or written
suggested solutions provided by the manufacturer should be followed.

NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure is performed by a physician at

CHAPTER 24—Studies

the bedside and that it takes about 30 minutes to
insert and position the catheter
That a local anesthetic will be injected at the site
of the catheter insertion and that this discomfort
will be the only pain experienced
That the catheter will remain in place for 3 to 4
days and that no discomfort will be experienced
when the catheter is in place or when the tests are
performed
That the catheter will be sutured in place at the
insertion site and bandaged to prevent movement
and infection
Prepare for the procedure:
Obtain a history or assessment of cardiac and
pulmonary system status and other known or
suspected medical conditions, previous tests and
procedures, and medication regimen.
THE PROCEDURE

The client is placed in a supine position in bed with
the selected site exposed and the client draped for
privacy. The equipment and supplies, including the
Swan-Ganz or the four-lumen pulmonary artery
catheter, are prepared per hospital policy or manufacturer direction. The site is shaved if necessary,
cleansed, and draped to provide a sterile field. A
local anesthetic is injected at the site, the catheter is
inspected for defects, and a puncture or cutdown
incision is made to access the vein. The catheter is
inserted into the peripheral vein and advanced into
the superior vena cava and right atrium. The balloon
is partially inflated to allow it to move with the
blood flow through the tricuspid valve and into the
right ventricle and pulmonary artery until it
becomes wedged into a smaller distal pulmonary
artery. Waveforms are recorded on a screen as the
catheter is advanced into the right heart to note any
tachycardia caused by catheter irritation and to
obtain baseline information. Medications can be
administered to prevent arrhythmias or right bundle
block if these risks should be present. PAP is
obtained while the catheter is positioned in the
pulmonary artery. The catheter is advanced into a
wedged position in one of the smaller pulmonary
arteries and inflated with 1 mL of air to obtain
PAWP. After a PAWP reading, the balloon is deflated
to prevent pulmonary tissue necrosis; it then moves
back into the pulmonary artery. The catheter is
observed on the screen for the waveforms indicating
its position. Cardiac output is measured with the
catheter in the pulmonary artery, not in the wedged
position. Ten milliliters of ice water is injected into
the proximal lumen, and a temperature–time curve
is obtained with the thermistor at the end of the
catheter. An x-ray verifies catheter placement, and

of Specific Organs or Systems

583

the catheter is sutured to the skin. Sterile dressings
are applied to protect and maintain cleanliness of
the insertion site.
Monitoring activities associated with pulmonary
artery catheter procedures include vital signs and
ECG. Frequency and types of monitoring depend on
client status, as do PAP and PAWP measurements.
The system is flushed and recalibrated after each
PAWP reading. When monitoring via a pulmonary
artery catheter is concluded, the balloon is deflated,
and the dressing and sutures are removed. The
catheter is removed with a slow and smooth motion.
Vital signs and ECG monitoring continue, and a
sterile dressing is applied to the insertion site.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after removal of the
pulmonary artery catheter include monitoring
the insertion site, vital signs, and ECG for complications.
Abnormal monitoring results, complications,
and precautions: Provide support to the client
and report any difficulty in obtaining readings
and flushing the system. Troubleshooting activities to correct pressure readings, catheter placement, monitoring device, or transducer problems
should be assessed and solved according to the
manufacturer’s instructions.
Infection, local/systemic: Note and report
redness, pain, swelling, drainage, or elevated
temperature. Administer antibiotic therapy. Apply
warm compresses to the site. Use strict aseptic
technique during insertion, while obtaining blood
samples, and during cardiac output measurement
and pressure monitoring.
Arrhythmias: Note and report changes in ECG
strip and vital signs. Administer ordered antiarrhythmics. Monitor vital signs and ECG.
Pulmonary emboli/infarction: Note and report
dyspnea, tachypnea, hypoxia, or chest pain.
Monitor vital signs. Administer ordered medications and oxygen. Place client in a semi-Fowler’s
position. Restrict time that the catheter is in a
wedge position.

HIS BUNDLE EVOKED POTENTIAL
STUDY
The His bundle evoked potential (EP) study is an
invasive electrophysiologic study using cardiac
catheterization to insert electrodes that measure and
identify defects in the electric conduction activity of
the heart. Heart muscle has the ability to generate
and conduct electric impulses. It also contains
special pacemaker cells that make up the conduction

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Tests and Procedures

system that controls the rhythm of the heart. Each
contraction is initiated by the sinoatrial (SA) node,
located in the posterior wall of the right atrium, and
passes down to the atrioventricular (AV) node. The
AV node connects the conduction systems that
control the atrial and ventricular activity. Fibers
within the AV node conduct the impulses into the
His bundle that extends into the ventricular system.
The normal velocity of the conduction system
through the atrium and ventricles is necessary for
the atrial emptying before ventricular contractions
and the proper ejection of blood from the heart by
the ventricular system.7
The procedure for the study is performed in the
same manner as cardiac catheterization, but it uses
bipolar or tripolar catheters that contain electrodes
instead of the luminal catheters. The catheter is
inserted into the femoral vein and advanced into the
right atrium, through the tricuspid valve, and into
the right ventricle under the guidance of fluoroscopy. The electrode at the end of the catheter
measures conduction intervals or times that indicate
nodal defects and cardiac arrhythmias. Conduction
intervals that are measured include the H-V, which
represents the time it takes for the electric activity to
pass from the His bundle to the Purkinje fibers of
the ventricular system, and the A-H, which represents the time it takes for the atrial node activity to
activate the His bundle.8 The study also can be
performed to induce an abnormal rhythm to
evaluate the effectiveness of antiarrhythmics or to
determine the need for pacemaker implantation.
Intracardiac electrograms are recorded from the
electrode on the catheter as it passes the His bundle.
Conventional 10-lead ECG monitoring is conducted
at the same time to obtain a recording of the total
electric activity of the heart.
Reference Values
Normal atrioventricular conduction system
intervals, recovery, and refractory times; no
arrhythmias and conduction disturbances
INTERFERING FACTORS

Improper placement of catheter
Equipment dysfunction or failure
Sedatives and antianxiety agents, which can alter
test results
INDICATIONS FOR HIS BUNDLE EVOKED
POTENTIAL STUDY

Providing a cardiac mapping of the entire
conduction system to evaluate normal and abnormal pathways of electric activity

Diagnosing and identifying heart conduction
defects and SA and AV nodes as revealed by shortened or delayed intervals
Determining the cause of syncope or cardiac
arrest episode
Diagnosing sick sinus syndrome as revealed by
prolonged recovery time or heart block as
revealed by prolonged conduction time
Determining the site of bundle branch block as
revealed by prolonged conduction interval in the
His bundle and Purkinje fibers
Diagnosing ventricular arrhythmias and determining appropriate therapy, or pacing the heart
and inducing an arrhythmia to evaluate the effectiveness of therapy by determining if the drug
prevents the arrhythmia
Determining cardiac pacing abnormalities and
need for pacemaker implantation
CONTRAINDICATIONS

Medical conditions such as coagulation disorder
Myocardial infarct, unless time is limited and
determination is made that the benefits of
performing the study outweigh the risks
Nursing Alert

Life-threatening arrhythmias can occur or can
be induced during this study, and emergency
equipment (defibrillator) and drugs (antiarrhythmics) should be on hand during the
procedure.

NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Cardiac Catheterization Study” section.
In addition, instruct the client to report any dizziness during the study; inform the client that
palpitations can be experienced when the heart is
paced and that sedatives or analgesics are not
administered before the study because they can
influence the accuracy of the results.
THE PROCEDURE

The procedure is the same as for cardiac catheterization (see earlier section) of the right side of the heart
via a vein, using a solid tubular electrode catheter
that is advanced into the right atrium and ventricle.
Fluoroscopy is used in guiding the catheter into the
chambers of the heart, and monitors allow visualization of the catheter. Electrograms from the catheter
and traditional ECG are obtained during the proce-

CHAPTER 24—Studies

dure. Baseline ECG readings are obtained, and
conduction intervals are recorded and measured as
the catheter passes along the ventricle wall and His
bundle. Atrial or ventricular pacing can be produced
by the catheter to induce arrhythmias for identification and to determine drug therapy effectiveness.
Also, drugs can be administered during the study to
determine their effectiveness in preventing an
induced arrhythmia. Support is given to the client to
allay fear during the study when pacing is
performed, and the client is reminded to report
symptoms such as palpitations or lightheadedness.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the procedure are the
same as those described in the “Cardiac Catheterization Study” section except that a contrast medium
is not used in this study.
Continue ECG and vital signs monitoring if drugs
are administered during the procedure or if
arrhythmias persist.
Thrombophlebitis/infection/bleeding at site:
Note and report excessive bleeding, hematoma
formation, pain, swelling, or drainage at the site.
Administer ordered antibiotics. Monitor vital
signs and peripheral pulses. Apply ice or warm
compress to the site as appropriate.
Adverse reaction to drugs: Note and report
abdominal cramps and hypotension resulting
from quinidine, hypotension resulting from
procainamide (Pronestyl), or behavior change
resulting from phenytoin (Dilantin). Monitor
heart activity via ECG. Administer IV fluid infusion.
Fibrillation/arrhythmias: Note and report
cardiac rhythm abnormalities. Administer
ordered antiarrhythmics and other treatments.
Monitor ECG. Have emergency fibrillation equipment and supplies on hand for life-threatening
arrhythmias.

COLD STIMULATION TEST
The cold stimulation test is a noninvasive peripheral
vascular procedure that is performed to provide
information to assist in diagnosing Raynaud’s
syndrome. The test measures temperature changes
in the fingers after exposure to cold temperature
changes and the time it takes for the finger temperature to return to normal after the cold stimulus has
been removed. It is usually performed when chronic
arterial occlusive disease has been ruled out as the
cause of signs and symptoms that indicate a peripheral vascular disorder.
The cause of Raynaud’s syndrome is a functional
abnormality resulting from an intense vasospasm of

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585

the small arteries and arterioles of the fingers and, in
some cases, the toes. The disorder can be classified as
Raynaud’s disease (primary type), which occurs
without any cause other than exposure to cold or
extreme stress, or Raynaud’s phenomenon (secondary type), which occurs as a result of occupational
trauma, arterial occlusive disease, or in association
with collagen diseases such as scleroderma and lupus
erythematosus. The vasospasms cause ischemia,
which changes the skin color from pallor to cyanotic, starting at the fingertips and traveling up the
distal portion of the phalanges. Tingling, numbness,
and cold sensation are experienced during ischemia.
After the ischemia, hyperemia occurs, with a change
in skin color to red, and a throbbing sensation is
experienced. The cause of Raynaud’s disease is
unknown but is believed to be associated with local
circulatory mechanisms (prostaglandins) and does
not affect the anatomic structure of the vessels.
Raynaud’s phenomenon, however, does involve
abnormal changes in the anatomic structure of the
vessels.9
Reference Values
Normal temperature, blood pressure, and skin
color of fingers and toes after exposure to cold
temperatures; no Raynaud’s disease or phenomenon
INTERFERING FACTORS

Extreme environmental temperatures
INDICATIONS FOR COLD STIMULATION TEST

Diagnosing Raynaud’s syndrome, as revealed by
inability of digits to return to pretest temperature
within a specific length of time, usually 20
minutes
Differentiating between Raynaud’s primary
disease and Raynaud’s phenomenon as a secondary disease associated with connective tissue
disorders
CONTRAINDICATIONS

Infectious process at the digit sites to be used in
the test
Advanced disease in which gangrene of the digits
is present and circulation impairment is evident
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the procedure is performed in the laboratory
by a physician or a staff technician and takes
about 30 minutes

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Tests and Procedures

That there are no food or fluid restrictions before
the study
That small devices connected to wires are
attached to the fingers, and the hand is immersed
in cold water while finger temperature is recorded
That only a slight discomfort may be experienced
when the hands are placed in the cold water and
that no pain is felt from the devices taped to the
digits
Prepare for the procedure:
Have the client void before the procedure.
Obtain a history of known or suspected scleroderma or lupus erythematosus, effects of temperature and stress on digital blood flow, treatments,
or previous tests and procedures.
THE PROCEDURE

The client is placed in a sitting position in a room
with optimal temperature control. A thermistor is
attached to each finger above the nail area. Wires
are attached to record temperature changes. The
temperature is recorded to obtain baseline measurements, and the hands are immersed in ice water
for 20 seconds. The hands are removed, and the
temperature is again recorded and continues to be
recorded every 5 minutes until the baseline level is
attained. A delayed return to baseline temperatures
of more than 20 minutes indicates Raynaud’s
syndrome.10
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study include
removing the thermistors and returning the
clothing and belongings to the client.

PULMONARY SYSTEM
Pulmonary system studies include procedures to
obtain diagnostic information about the lungs and
their ability to provide oxygen to and remove carbon
dioxide from the body tissues and organ systems.
This process is known as gas exchange, and it is
dependent on respiratory function that involves
ventilation (inspiration and expiration), diffusion
(movement of gases across the alveolar capillary
membrane), and perfusion (movement of blood
through the pulmonary vasculature to body tissues).
These studies, along with arterial blood gas (ABG)
studies (see Chapter 5), are performed to determine
the existence or extent of pulmonary disease or
abnormalities to support information obtained by
medical history, chest radiography, lung scans, and
pulmonary angiography. Also included in this
section is the sweat test, performed to determine
alterations associated with cystic fibrosis in children

because the disease has a major effect on pulmonary
function.
Procedures associated with the pulmonary system
are usually performed in special laboratories, clinics,
or a physician’s office by a trained technician with a
physician present, if warranted. A signed informed
consent form is not required for these studies.

PULMONARY FUNCTION STUDY
Pulmonary function is a noninvasive study that
provides information about the volume, pattern,
and rates of flow involved in respiratory function to
assist in the diagnosis of insufficiencies associated
with pathophysiological abnormalities such as
tumors, infections, and obstructive and restrictive
disorders. It can also include tests involving the
distribution (pulmonary circulation that facilitates
gas exchange) and diffusing capabilities of the lungs
(volume of gases that diffuse across a membrane). A
complete pulmonary study profile includes the
determination of all lung volumes, spirometry,
diffusing capacity, maximum voluntary ventilation,
flow-volume loop, and maximum expiratory and
inspiratory pressures.11 Other studies include diffusing capacity and small airway volumes. ABGs also
reveal the distribution and diffusing capabilities of
pulmonary function (see Chapter 5). Some or all of
the tests can be performed to obtain the necessary
clinical assessment of the pulmonary airways, alveoli, and vascular function, depending on client
history and status. Modifications that include only
the more common tests can be performed at the
bedside or in outpatient settings, but a comprehensive study must be performed in a pulmonary function laboratory and values must be determined by
computer.
The process of respiration is the body’s means of
gas exchange in providing oxygen to and removing
carbon dioxide from the tissues; the process consists
of ventilation (movement of gases in and out of the
lung), perfusion (blood flow within the lung tissue),
and diffusion (movement of oxygen and carbon
dioxide across the alveolar membranes). It can be
divided anatomically into airways of different sizes
(nose, trachea, bronchi, bronchioles) that conduct
the gases, and the tissues (alveoli, pulmonary capillaries) that control gas exchange.
Respiration is controlled by the respiratory center
in the medulla of the brain with two groups of
neurons, one that is primarily concerned with inspiration and control of the impulses from the lungs
and airways that compose the ventilatory response,
and a second that is concerned with both inspiration
and expiration and control of the spinal motor

CHAPTER 24—Studies

neurons of the intercostal and abdominal muscles.
Breathing control is achieved by automatic regulation of ventilation by chemoreceptors and lung
receptors. The chemoreceptors are located in the
medulla (central) or in the carotid and aortic bodies
(peripheral), and they monitor levels of oxygen,
carbon dioxide, and pH in the blood. The chemoreceptors have the ability to adjust ventilation patterns
to the body’s metabolic requirements. Lung receptors are located in the airways and monitor breathing patterns and lung function by adjusting rate and
volume to accommodate changes in lung compliance, airway resistance and pressure, and lung
congestion.
Breathing can also be controlled through voluntary regulation, which provides the ability to
suspend automatic breathing such as by holding the
breath or by integrating breathing with activities
such as eating, speaking, and singing. The mechanics of breathing involve the inspiration of air, which
increases the volume of the thoracic cavity as the
intercostal muscles contract, enlarging the chest; the
diaphragm contracts, forcing the abdominal
contents down as the chest expands. This process
lowers the alveolar pressure below the atmospheric
pressure and allows the air to flow into the large and
small airways and alveoli. During expiration of air,
elasticity of the chest wall and lung recoil cause the
lung volume to decrease and the pressure to become
greater than the atmospheric pressure, which allows
the air to flow out of the lungs. Although expiration
is a passive event, intercostal and abdominal muscles
can be used if needed to increase this effort.12
Pulmonary function studies are classified into
lung volumes and capacities, rates of flow, and
gas exchange. Except for the gas exchange tests,
pulmonary function tests are measured by spirometry, which allows the recording of the amounts of a
gas present during inspiration and expiration. Lung
volumes and capacities are the amounts of air that
are inhaled or exhaled from the lungs compared
with normal reference values, using age, height,
weight, and gender of the client. The volumes and
capacities measured by spirometry without regard to
time limits include the following:
Tidal volume (TV): Total amount of air inhaled
and exhaled with one breath
Residual volume (RV): Amount of air remaining
in the lungs after a maximum expiration effort
(not measured by spirometry, but it can be
calculated from the functional residual capacity minus the expiratory reserve volume; indirect measurement can be achieved by body
plethysmography [see Chapter 22])

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587

Inspiratory reserve volume (IRV): Maximum
amount of air inhaled at the point of maximum expiration
Expiratory reserve volume (ERV): Maximum
amount of air exhaled after a resting expiration; can be calculated by the vital capacity
minus the inspiratory capacity
Vital capacity (VC): Maximum amount of air
exhaled slowly at the point of maximum inspiration; can be calculated by adding the inspiratory capacity and the expiratory reserve
volume
Total lung capacity (TLC): Total amount of air
that the lungs can hold after maximum inspiration; can be calculated by adding the vital
capacity and the residual volume
Inspiratory capacity (IC): Maximum amount of
air inspired after normal expiration; can be
calculated by adding the inspiratory reserve
volume and the tidal volume
Functional residual capacity (FRC): Volume of
air that remains in the lungs after normal expiration; can be calculated by adding the residual
volume and expiratory reserve volume
The pulmonary function studies for lung
volumes, capacities, and rates of flow measured
by spirometry that involve timing include the
following:
Forced vital capacity (FVC): Maximum amount
of air that can be forcefully exhaled after a full
inspiration
Forced expiratory volume in 1 second (FEV1):
Amount of air exhaled in the first second of
forced vital capacity; can also be determined at
2 or 3 seconds. The percentage of FVC is the
amount of air exhaled in seconds expressed in
percent (%)
Maximum midexpiratory flow (MMEF):
Maximum rate of air flow during a forced expiration
Forced inspiratory flow (FIF) rate: Volume
inspired from the residual volume at a point of
measurement; can be expressed as a percentage
to identify the corresponding volume pressure
and inspired volume
Peak inspiratory flow rate (PIFR): Maximum
flow of air during a forced maximum inspiration
Peak expiratory flow rate (PEFR): Maximum
flow of air expired during forced vital capacity
Flow-volume (F-V) loop: Continuous flow rates
and volumes displayed on a screen during
forced expiratory and inspiratory vital capacity
procedures

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Tests and Procedures

Maximum inspiratory/expiratory pressures:
Measures the strength of the respiratory
muscles in neuromuscular disorders
Maximum volume ventilation (MVV):
Maximum volume of air inspired and expired
in 1 minute
Other studies for gas exchange capacity, small
airway abnormalities, and allergic responses in
hyperactive airway disorders can be performed
during the conventional pulmonary function study
and include the following:
Diffusing capacity of lungs (DL): Rate of transfer
of carbon monoxide through the alveolar and
capillary membranes in 1 minute
Closing volume (CV): Measure of the closure of
small airways in the lower alveoli by monitoring volume and percent of alveolar nitrogen
after inhalation of 100 percent oxygen
Isoflow volume (isoV): Flow-volume loop test

followed by inhalation of mix of helium and
oxygen to determine small airways disease
Body plethysmography: Measures thoracic gas
volume, airway resistance, and lung compliance Bronchial provocation: Detects airway
sensitivities after inhalation of methacholine in
those with asthma
Arterial blood gases (ABGs): Measures oxygen
and carbon dioxide in arterial blood in the
determination of hypoxia (see Chapter 22);
reveals the perfusion and diffusion capabilities
of pulmonary function
The findings or measurements are recorded on a
spirogram that is used to diagnose or differentiate
between obstructive and restrictive lung diseases.
Values are expressed in units of milliliter (mL),
percent (%), liter (L), liter per second (L/sec), or
liter per minute (L/min), depending on the test
performed.

Reference Values
Normal respiratory volume and capacities, gas diffusion, and distribution; no obstructive or
restrictive lung disease
Lung Volumes, Capacities, and Flow Rates (values based on age, gender, height, and weight)
TV

500 mL at rest

1200 mL (approximate)

IRV

3000 mL (approximate)

ERV

1100 mL (approximate)

4600 mL (approximate)

TLC

5800 mL (approximate)

3500 mL (approximate)

FRC

2300 mL (approximate)

FVC

3000–5000 mL (approximate)

FEV1

81–83%

MMEF

25–75%

FIF

25–75%

MVV

25–35% or 170 L/min

PIFR

300 L/min

PEFR

450 L/min

F-V loop

Normal curve

25 mL/min/mm Hg (approximate)

10–20% of VC

isoV

Based on age formula

Bronchial provocation

No change or less than 20% reduction in FEV1

CHAPTER 24—Studies

INTERFERING FACTORS

Client confusion or inability of client to understand instructions or cooperate during the study
The aging process (can cause increases or
decreases in values, depending on the study)
Inability of client to put forth the necessary
breathing effort
Bronchodilators or narcotic analgesics (can
change breathing patterns)
Improper placement of the nose clamp or mouthpiece, allowing leakage
INDICATIONS FOR PULMONARY FUNCTION
STUDY

Diagnosis and differentiation between pulmonary
obstructive and restrictive disease or a combination of both revealed by abnormal expired or
inspired volumes, respectively
Determination of the presence of lung disease
when other studies such as x-rays do not provide
a definitive diagnosis or determination of the
progression and severity of known obstructive
and restrictive lung disease
Diagnosis of chronic obstructive pulmonary
diseases (COPDs) that affect the peripheral
airways (asthma, bronchitis), parenchyma (emphysema), and upper airways (tumors of pharynx,
larynx, trachea, infections, or foreign body)
Diagnosis of chronic restrictive pulmonary
diseases that affect the chest wall (neuromuscular
disorders, kyphosis, scoliosis), interstitium (pneumonitis, fibrosis), pleural conditions (pneumothorax, hemothorax), lesions (tumors, cysts), and
other conditions such as obesity, ascites, or peritonitis
Dyspnea with or without exertion, coughing, and
wheezing to determine the cause
Determination of the effectiveness of therapy
regimens while following the course of a
pulmonary disorder and identification of bronchospasm response to long-term administration
of bronchodilators
Evaluation of the lungs and respiratory status to
determine the ability of the client to tolerate
procedures such as surgery or diagnostic studies,
especially on the lungs
Screening of high-risk populations for early
detection of pulmonary conditions (those who
smoke, those whose occupations require exposure
to potentially harmful inhalants, and those who
have a hereditary predisposition)
Evaluation of a pulmonary function after surgical
pneumonectomy, lobectomy, or segmental lobectomy

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589

Evaluation of pulmonary disability for legal or
insurance claims
Determination of allergic response to inhalants in
those with an airway reactive disorder
Evaluation of lung compliance to determine elasticity as revealed by changes in lung volumes,
which are decreased in restrictive disease and
increased in obstructive disease and in elderly
people
Determination of the diffusing capacity of the
lungs in diagnosing CHF, adult respiratory
distress syndrome, and collagen vascular disorders13
CONTRAINDICATIONS

Medical conditions such as cardiac insufficiency
or recent myocardial infarct
Presence of chest pain that affects inspiration or
expiration ability
Upper respiratory infection such as a cold or acute
bronchitis
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That medications such as bronchodilators (oral or
inhalant) and smoking should be avoided for at
least 4 hours before the study
That the study takes about 1 hour, depending on
the number of tests performed
That food and fluids are allowed before the study
but that a large meal should be avoided, because it
creates pressure against the diaphragm that can
affect breathing
That a clamp is placed on the nose and that the
client is requested to breathe through the mouth
into a tube
That the client is requested to perform various
breathing patterns during the study
That no pain is associated with the study
Prepare for the procedure:
Obtain height and weight for use in determining
the normal range in interpreting results.
Ensure that medication and smoking restrictions
have been followed.
Take vital signs and note any respiratory abnormalities such as dyspnea.
Have client void before the procedure for
comfort.
Obtain a history of suspected or known
pulmonary conditions, respiratory status and
patterns, medications (oral, inhalant, other), and
previous tests and procedures.
THE PROCEDURE

The client is placed in a sitting position on a chair

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SECTION II—Diagnostic

Tests and Procedures

near the spirometry equipment. A soft clip is placed
on the nose to restrict nose breathing, and the client
is instructed to breathe through the mouth. The
client is allowed to practice breathing rapidly and
deeply through the mouth in preparation for the
tests. A mouthpiece is placed in the mouth, and the
client is requested to close the lips around it to form
a seal. The client is then requested to inhale deeply
and to quickly exhale as much air as possible into the
mouthpiece. Other breathing maneuvers are
performed on inspiration and expiration (normal
and forced) and holding of the breath, depending on
the test that is being performed. The tests can also be
timed to obtain information for specific tests. The
tubing from the mouthpiece is connected to a cylinder that is connected to a computer that measures
and records the values for the tests. Some measurements can be calculated with the values obtained
from the computer printout. A bronchodilator can
be administered, with the test repeated to determine
whether ventilation improves over the predicted
value for the client in the diagnosis of pulmonary
disease.
The lung diffusing capacity test is performed by
having the client take a deep breath of a gas mixture
(10 percent helium [He] and 0.3 percent carbon
monoxide [CO] and room air) from a bag, holding
the breath for 10 seconds, and then exhaling. The
measurement of the amount of the functioning
capillary bed in contact with the alveoli and the alveoli volume are then calculated. Another method
involves breathing from a bag of a gas mixture (0.1
to 0.2 percent CO) for a few minutes, after which the
exhaled air in the bag is analyzed for oxygen, carbon
dioxide, and carbon monoxide concentrations. ABG
analysis is also performed for this method of testing
for diffusing capacity.14
The bronchial provocation test is performed after
the FVC test. Inhalation of 1.25 mg of methacholine
is administered, and a repeat FVC is performed after
waiting about 5 minutes. A reduction in FEV1
reveals a positive response for bronchial asthma. If
no change is revealed, the dosage of medication is
gradually increased and, if the FEV is not reduced
after 5 dosage dilutions, the result is considered a
negative response. A histamine challenge test can
follow if no change in FEV is noted. An inhalant
bronchodilator should be on hand to treat any bronchospasms that occur with these tests.15
At the conclusion of the tests, the mouthpiece and
nose clip are removed, and the client is taken to
another room to rest.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study include allow-

ing the client to rest in a comfortable chair
because clients with impaired pulmonary function can become fatigued by the procedure.
Resume medications that have been withheld and
offer water for a dry mouth.
Monitor respirations for dyspnea or breathlessness in clients with severe pulmonary disease.
Bronchospasms/respiratory distress: Note and
report dyspnea, tachycardia, or apprehension.
Administer ordered inhalant bronchodilators.
Monitor vital signs.

EXERCISE PULMONARY FUNCTION
STUDY
Exercise pulmonary function is a noninvasive
study that evaluates the ability to perform exercises
or other activities in clients with obstructive or
restrictive lung disorders. It assists in determining
the extent or severity of respiratory impairment.
Testing identifies the level of tolerance through
a display of fatigue and dyspnea on a bicycle
ergometer during exercise. Activity causes increased
oxygen (O2) consumption and carbon dioxide
(CO2) production, and this study reveals the
ability of the pulmonary system to adapt to increases
in exercises. The study includes measurements
of O2 needed to accommodate activities and
spirometry measurements of air volume and flow.
Blood pressure, pulse, and respiration are also
monitored during the study. The exercises are
increased in increments until the maximum level is
attained. More complex pulmonary exercise tests
can be performed, based on abnormal results such as
measurements of mixed venous CO2 tension and
ABGs; additional ventilatory tests and ratios can be
used to obtain more specific diagnostic information.16
Reference Values
Normal pattern of air flow during respirations
(inspiration and expiration) while exercising;
normal ABGs during exercising; no dyspnea
caused by respiratory disease

INTERFERING FACTORS

Obesity, which can affect the results because more
oxygen is consumed with exercise
Weakness and poor physical condition
Impaired cardiac status
Degree of abnormal gas exchange and ventilation
impairment

CHAPTER 24—Studies

INDICATIONS FOR EXERCISE PULMONARY
FUNCTION STUDY

Evaluating severity of pulmonary impairment in
those with respiratory disease to determine status
or progression of disease
Diagnosing psychogenic dyspnea as revealed by
absence of abnormal response during the test in
those with complaints of shortness of breath
Evaluating activity tolerance in those with known
pulmonary impairment before planning and
prescribing pulmonary rehabilitation
Diagnosing asthma induced by exercise
Differentiating dyspnea caused by pulmonary or
cardiac conditions and determining abnormal
states that contribute to a decrease in activity
intolerance
CONTRAINDICATIONS

Medical conditions such as respiratory failure,
epilepsy, pulmonary edema, and acute illnesses
Uncontrolled asthma or hypertension with
systolic pressure greater than 250 mm Hg and
diastolic pressure greater than 120 mm Hg17
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the client should wear comfortable clothing
and shoes
That pulse, respirations, and blood pressure are
monitored throughout the procedure
That the client will exercise by pedaling a bicycle
with increases in speed as the tests are performed
That the client will be requested to breathe
through the mouth into a mouthpiece with the
nose clamped
That no pain is associated with the study unless
more advanced tests are performed that require
arterial blood samples
Prepare for the procedure:
Obtain baseline vital signs and note any breathing
pattern abnormalities.
Have the client void before the procedure.
Obtain age, weight, height, and history of
suspected or known pulmonary conditions,
medications and time of last doses, and previous
tests and procedures.
THE PROCEDURE

The client is seated on the bicycle adjusted to the
proper height, and the feet are strapped to the
pedals. A soft clip is placed on the nose to restrict
nose breathing, and the client is instructed to
breathe through the mouth. A mouthpiece is placed
in the mouth, and the client is requested to close the

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lips around it to form a seal. The client is requested
to start pedaling while breathing through the
mouthpiece, which is attached to the computerized
equipment that measures the pulse, blood pressure,
and respiratory rates while the spirometry component measures expiratory air flow and tidal volume
for each minute of exercise. Exercising is increased in
increments until the client can no longer tolerate the
continued pedaling. In some testing, 100 percent
oxygen is administered to determine the amount of
oxygen therapy needed to improve activity tolerance, if improvement is a possibility. The results are
analyzed and recorded by the computer. More extensive testing to obtain additional measurements
includes rebreathing maneuvers and ABG analysis,
which extends the testing time up to 2 hours.
At the conclusion of the test, the mouthpiece and
nose clip are removed, and the client is assisted off
the bicycle and to a chair to rest.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the study include allowing the client to rest until respirations return to
normal.
Resume any medications withheld before the
study.
Monitor respirations for continued dyspnea in
clients with severe pulmonary impairment.
Respiratory distress: Terminate test early if
extreme dyspnea, exhaustion, cyanosis, or vital
sign changes indicate possible respiratory arrest.
Have aminophylline and emergency resuscitation
equipment on hand.

OXIMETRY
Oximetry, also known as pulse oximetry, is a noninvasive study that provides continuous readings of
arterial blood oxygen saturation (SaO2) by using a
sensor site (earlobe or fingertip). Oxygen is transported in combination with hemoglobin (Hgb) or
dissolved in blood plasma, with 99 percent of the
oxygen used by the body tissues carried by Hgb.
About 95 to 97 percent is carried if the Hgb is saturated with O2, because a small amount of unoxygenated blood from the bronchial circulation is
mixed with the oxygenated blood in the pulmonary
veins. The SaO2 equals the ratio of the amount of O2
in the Hgb to the maximum amount of Hgb
expressed in percent.
This procedure is performed to monitor oxygenation status that compares favorably with oxygen
saturation levels obtained by ABG analysis without
the need to perform successive arterial punctures.
The device is a clip or probe containing a sensor that

592

SECTION II—Diagnostic

Tests and Procedures

increases the blood flow to the site and produces a
light beam through the tissues at the site. The sensor
measures the absorption of the light to determine
the oxygen saturation reading, which is recorded on
a stationary or portable screen for viewing.18

That no pain is associated with the test
Prepare for the procedure:
Obtain a history of pulmonary disorders, respiratory and cardiac status, vital signs, reasons for
monitoring procedure, and ABG results.
THE PROCEDURE

Reference Values
Normal arterial blood oxygen saturation of
95 percent or more
INTERFERING FACTORS

Movement of the finger or ear affects the measurement readings.
Anemic conditions with a reduction in Hgb, the
oxygen-carrying component in the blood, affect
measurement readings.
Vasoconstriction from cool skin temperature,
drugs, hypotension, or vessel obstruction causes a
decrease in blood flow readings.
INDICATIONS FOR OXIMETRY

Monitoring of oxygenation of tissues and organs
postoperatively and during acute illnesses to
determine impaired cardiopulmonary function
Monitoring of oxygenation status in clients on a
ventilator
Suspected nocturnal hypoxemia in COPD to
measure oxygen saturation during nocturnal
oxygen therapy
Monitoring of oxygen saturation during activities
such as pulmonary exercise stress testing or
during pulmonary rehabilitation exercises to
determine optimal tolerance
Determination of effectiveness of pulmonary gas
exchange function
Monitoring of response to pulmonary drug regimens, especially bronchodilators, to determine
effectiveness in promoting air flow and oxygen
content
Monitoring of oxygenation during testing for
sleep apnea
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test is performed by the nurse, technician, or respiratory therapist, depending on the
reason for the monitoring
That a clip will be placed on the upper ear,
earlobe, or finger and attached to a monitor that
records the oxygen measurements
That the test will last as long as monitoring is
needed and can be continuous if done after
surgery or for acute pulmonary conditions

The ear or finger is massaged to increase blood flow
to the area. The oximetry probe clip is placed on the
site. Blood flow is warmed and increased to the area
by the sensor or probe. As a beam of light is passed
through the tissue at the site, the sensor measures
the amount of light that is absorbed.19 The reading
of this measurement is recorded on a monitor
(stationary or portable handheld).
At the conclusion of the test or monitoring, the
clip is removed.
NURSING CARE AFTER THE PROCEDURE

No special care is required after this procedure.
Hypoxemia: Note and report measurements of
less than 95 percent. Note extreme measurement
of 75 percent as a critical value requiring immediate interventions. Monitor oximetry readings
and vital signs. Have oxygen, ventilator, and other
resuscitation equipment on hand.

SWEAT TEST
The sweat test, also known as the pilocarpine
iontophoresis sweat test, is a noninvasive study
performed to obtain a definitive diagnosis of cystic
fibrosis in children when considered with other test
results and physical assessments. Cystic fibrosis is a
hereditary disease characterized by elevated sodium
chloride (NaCl) in the sweat, chronic lung disease,
and pancreatic insufficiency. This test measures the
sodium (Na) and chloride (Cl) content in the sweat
produced by the sweat glands of the skin after
inducement to increase its production by a small
electric current carrying the drug pilocarpine. An
analysis of the collected sweat is performed to determine sodium and chloride content, with high
concentrations indicating the presence of the
disease. The newborn is not a candidate for this test
because the amount of sweat produced is insufficient for testing.
Screening for cystic fibrosis can be performed
with the use of a silver nitrate test paper and validation of a positive test by pilocarpine iontophoresis.20
A new battery-operated device that uses patches on
the skin that change color when sweat chloride levels
are elevated after induction of sweating by pilocarpine iontophoresis is also used to perform this
test.21

CHAPTER 24—Studies

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593

Reference Values
Conventional Units

SI Units

Sodium concentration in sweat

10–40 mEq/L

10–40 mmol/L

Chloride concentration in sweat

0–35 mEq/L

0–35 mmol/L

Note: No cystic fibrosis values of greater than 70 mEq/L sodium or greater than 50 mEq/L chloride in children.

INTERFERING FACTORS

Inadequate amount of sweat to perform test accurately
Improper cleansing of skin or application of
gauze pad or paper
Hot environmental temperatures that can
reduce sodium chloride or cool environmental
temperatures that affect the amount of sweat
collected
INDICATIONS FOR SWEAT TEST

Diagnosis or confirmation of cystic fibrosis in
children
Screening for cystic fibrosis in those with a family
history of the disease
Suspected cystic fibrosis in failure-to-thrive
infants or malabsorption syndrome or recurrent
respiratory infections in children
Nursing Alert

The test should be terminated if the client
complains of burning at the electrode site, and
the electrode should then be repositioned
before the test is resumed. The site for electrode placement should never include the
chest because of the risk for cardiac arrest
from the current.

NURSING CARE BEFORE THE PROCEDURE

Inform the client that an electrode is placed on the
forearm, thigh, and possibly the back and that
sweat is collected for laboratory analysis of
sodium and chloride content.
Assurance should be given that no pain is associated with the test but that a stinging sensation can
be experienced at the site and that the electric
current causing it is delivered at a very low level.
The history should include the presence of cystic
fibrosis in other members of the family, endocrine
disorders, failure to thrive, respiratory status, and
malabsorption syndrome as well as results of
other tests.

THE PROCEDURE

The client is placed in a position to allow exposure of
the site on the forearm. If the client is a small infant,
two sites (back and thigh) can be used to ensure the
collection of an adequate amount of sweat. The
client should be covered to prevent evaporation
caused by cool environmental temperatures, which
affect sweat collection. The site is washed with
distilled water and dried. A positive electrode is
attached to the site and covered with a pad that is
saturated with pilocarpine hydrochloride, a drug
that stimulates sweating. A negative electrode is
covered with a pad that is saturated with bicarbonate solution. Iontophoresis is achieved by supplying
a low-level electric current via the electrode for 5 to
12 minutes. Battery-powered equipment is preferred
over an electrical outlet to supply the current. The
electrodes are removed, revealing redness at the site,
and the site is washed with distilled water and dried
to remove any possible contaminants on the skin.
Disks made of filter paper are weighed, placed on the
site with a forceps, and covered with paraffin to
prevent any possible evaporation of the sweat
collected. The disks are left in place for about 1 hour,
the paraffin removed, and the disks placed in a
preweighted flask with a forceps. The flask is sent to
the laboratory for weighing and analysis for sodium
and chloride content.22 At least 100 mg of sweat is
required for testing.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include washing
and drying the site and assessing it for any
unusual sensations or redness.
Place the stopper in the flask containing the filter
paper and take it to the laboratory immediately.
Assess the site for unusual color or discomfort.
Inform the client that the redness at the site will
fade in 2 to 3 hours.
Provide support if necessary when diagnostic
findings are revealed and assist the client or caregiver, or both, to cope with long-term implications (effect on organs and systems, early death).
If cystic fibrosis is diagnosed, provide referral for

594

SECTION II—Diagnostic

Tests and Procedures

genetic counseling, further education, and possible screening of other members of the family.

NEUROLOGICAL SYSTEM
Neurological system studies primarily include
procedures to obtain diagnostic information
about otological and ophthalmologic conditions.
Emphasis is placed on those procedures that provide
assessment data about auditory and visual deficits
that lead to diagnosis and treatment regimens to
correct sensory impairments. Tests that have
commonalities in the data collection or obtained
information are grouped under general headings.
Neuromuscular tests that are included in this section
are spinal nerve root thermography and the Tensilon
test.
The procedures can be performed in various
settings by a physician, nurse, or trained technician,
depending on the test. A signed informed consent
form is not needed unless specified.

tion and change the heat course of a specific
dermatome
Leg asymmetry caused by varicose veins, if the
legs are scanned
INDICATIONS FOR SPINAL NERVE ROOT
THERMOGRAPHY

Diagnosis of herniated intervertebral disk that
presses on a nerve root as revealed by an abnormal and asymmetrical heat pattern along the
dermatome course
Evaluation of preoperative and postoperative
status of a lumbar herniated intervertebral disk as
revealed by a change from asymmetrical to
symmetrical heat emission in the thighs and a
diffusion of heat emission in the lower back
region
Chronic or acute back pain to determine the
cause, such as nerve root irritation or soft tissue
injury
NURSING CARE BEFORE THE PROCEDURE

SPINAL NERVE ROOT THERMOGRAPHY
Spinal nerve root thermography is a noninvasive
study that measures and compares the heat emitted
from the surface of the skin at two adjacent areas of
the spinal column (lumbar, thoracic, cervical). It is
performed to detect sensory nerve irritation, which
causes distinct heat patterns at the skin sites of
peripheral afferent fibers, indicating nerve root
injury.23 Spinal nerves divide into two roots: One is
the dorsal root, which carries afferent neuron axons
into the central nervous system (CNS), and the
other is the ventral root, which carries the axons
of the afferent neurons to the periphery. The irritation of these nerve roots by conditions such as a
ruptured intervertebral disk or soft tissue injuries
produces abnormal heat levels, which are revealed by
this study. The most common site tested is the
lumbar region to assist in diagnosing the cause of
low back syndrome. This study can be performed in
conjunction with myelography, electromyography
(EMG), and computerized scanning diagnostic
procedures.
Reference Values
Normal diffusion of heat patterns of lumbar,
thoracic, and cervical spinal nerve areas; no
nerve irritation or soft tissue trauma
INTERFERING FACTORS

Changes in room temperatures
Smoking before the test, which can affect circula-

Explain to the client:
That the procedure is performed in a specially
equipped room in the radiology department by a
technologist and that it takes about 60 to 90
minutes
That there are no food or fluid restrictions but
that smoking should be restricted for 4 to 6 hours
before the test
That no lotions or powders should be applied to
the scanning sites before the study
That a device will scan the areas to determine the
heat emitted from the skin surfaces
That there is no pain or radiation associated with
this study
Prepare for the procedure:
Assist the client in removing clothing from the
waist down for lumbar studies and from the waist
up for cervical studies, and provide a gown.
Wash the areas of any lotions or powders that
might be present and pat dry.
Have client void before the procedure.
Obtain a history of musculoskeletal conditions;
severe or chronic pain in a spinal area, legs, or
arms; last physical therapy session; and past tests
and procedures; note whether EMG has been
performed on the day of the study.
THE PROCEDURE

The client is placed in a prone position with the
lower back, buttocks, and legs exposed and draped
or the back of the neck, shoulders, and arms exposed
and draped, depending on the area to be scanned.
The skin sites are cooled with water at room temper-

CHAPTER 24—Studies

ature (68F [20C]) or with alcohol in a spray bottle
and are blown dry with a hair dryer. The client is
requested to lie quietly and relax for 10 minutes. An
electronic apparatus containing infrared sensors is
placed on two adjacent areas of skin surfaces and
scanning is performed over the lower back, buttocks,
and both legs for lumbar examination or over the
back of the neck and both shoulders and arms for
cervical examination. Heat patterns and any changes
are measured, and views are photographed for
analysis. A difference between the temperature of the
surface on one side and that on the other side is
considered an abnormality. Local abnormalities
indicate soft tissue injury, and an abnormality that
follows a specific course indicates sensory nerve irritation.24
NURSING CARE AFTER THE PROCEDURE

No special aftercare is required for this test.
Chronic pain: Note and report severity and characteristics of pain. Support positioning of painful
areas during and after the study. Administer
ordered analgesic.

TENSILON TEST
The Tensilon test is a pharmacological challenge
study performed to assist in the diagnosis of myasthenia gravis. The drug used is edrophonium chloride (Tensilon), a short-acting form of the drug
used to treat this disorder. The test involves the IV
administration of the drug before and during the
performance of various muscular movements and
the evaluation of these movements for changes in
muscle strength. A positive diagnosis is made when
the administration of the drug results in an
improvement in muscle function. A negative diagnosis is made if muscle fasciculations occur as a
result of the drug.
Myasthenia gravis is a disease affecting the neuromuscular junction. It is caused by a deficiency of
acetylcholine receptor sites on the muscle side of
the junction. It is thought that the reduction in
these sites is caused by an autoimmune response
that blocks the receptor site and is responsible
for receptor destruction. The most prominent
symptom of the disease is weakness of the involved
muscles, which progresses in severity to all areas of
Reference Values
Absence of muscle fasciculations after injection
of edrophonium chloride; no myasthenia gravis
revealed, that is, no muscle weakness or autonomic dysfunction

of Specific Organs or Systems

595

the body.
INTERFERING FACTORS

Corticosteroids, muscle relaxants, and anticholinergics, which can alter test results by their effect
on muscle function or on the action of Tensilon
INDICATIONS FOR TENSILON TEST

Diagnosing myasthenia gravis when fatigue and
muscle weakness are present, as revealed by an
immediate improvement after injection of
Tensilon
Monitoring medication regimen of oral anticholinesterase to determine whether increase in
dose is advised, as revealed by an improvement in
muscle strength after IV Tensilon
Determining whether an overdose is present,
which can place the client in cholinergic crisis, as
revealed by an exaggeration of muscle weakness
after IV Tensilon
CONTRAINDICATIONS

Breathing difficulties or apneic conditions,
because the disease can cause respiratory difficulties severe enough to require ventilatory support
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test is performed by a physician in an
examining room equipped with all necessary
supplies and that it takes about 30 minutes
That the nurse will remain with the client during
the entire test because the medication can have
some side effects
That any side effects from the medication will
disappear quickly
That there are no food or fluid restrictions, but
that some medications that can affect muscle
function are withheld before the test
That the medication for the test is administered
IV (or intramuscularly in a child)
That the client is requested to make repeated
movements during the test to check muscle function and that several tests can be performed to
ensure acceptable results
That no pain is associated with the test
Prepare for the procedure:
Have the client void before the test.
Obtain a history of respiratory/musculoskeletal
disorders; drug sensitivities; medication regimen
that includes medications that affect muscle
function, anticholinesterase therapy, and time
and amount of last dose; and previous diagnostic
procedures.

596

SECTION II—Diagnostic

Tests and Procedures

THE PROCEDURE

HEARING LOSS AUDIOMETRY

The client is placed in a supine or a sitting position
on the examining table, with the arm to be used for
the IV exposed and supported with an armboard. An
infusion of 5 percent glucose in water or normal
saline is started, and an initial dose of Tensilon is
administered, usually about 2 mg for an adult, with
adjustments based on weight in kilograms for children. The client is requested to perform activities to
fatigue the muscles, such as holding the arms up or
looking up until the arms or eyelids drop. The
remaining 8 mg of Tensilon is then administered
over a 30-second period to a total dose of 10 mg. The
client is then requested to perform muscle movements such as crossing and uncrossing the legs,
opening and closing the eyes, and raising and lowering the arms. Observations for muscle strength
improvement are made, and a dramatic improvement indicates that the weakness is caused by myasthenia gravis. The test is repeated to ensure accuracy
if muscle strength does not improve after the injection. Atropine is administered during the test for
those clients with asthma to decrease the side effects
of the Tensilon. Oral anticholinesterase medication
regimen is evaluated by infusion of 2 mg of Tensilon
1 hour after a dose of the anticholinesterase medication. A brief improvement in muscle strength indicates that an increase in therapy would be beneficial.
A decrease in muscle strength indicates that a reduction in therapy is needed. Differentiation between
myasthenic and cholinergic crisis is evaluated by the
infusion of 1 to 2 mg of Tensilon and the observation for muscle strength improvement or respiratory
difficulty. In the absence of muscle strength
improvement, another 5 mg can be infused, 1 mg at
a time, under close observation for any distress.
Resuscitation equipment should be on hand, as well
as atropine for treatment of cholinergic crisis and
neostigmine for treatment of myasthenic crisis, to be
administered IV.25

Hearing loss audiometry involves the quantitative
testing for a hearing deficit by using an electronic
instrument called an audiometer that measures
and records thresholds of hearing by air conduction and bone conduction tests. These results
determine whether the hearing loss is conductive,
sensorineural, or a composite of both. An elevated
air conduction threshold with a normal bone
conduction threshold indicates a conductive hearing
loss. An equally elevated threshold for both air and
bone conduction indicates a sensorineural hearing
loss. An elevated threshold of air conduction that is
more than an elevated threshold of bone conduction
indicates a composite of both types of hearing loss.
A conductive hearing loss is caused by an abnormality in the external auditory canal or middle ear; a
sensorineural hearing loss is caused by an abnormality in the inner ear or of the auditory (eighth)
nerve.26 Sensorineural hearing loss can be further
differentiated clinically by sensory (cochlear) or
neural (eighth nerve) lesions. Some common causes
of conductive hearing loss include otosclerosis,
middle ear infection, and obstruction or infectious
process of the external ear. Causes of sensorineural
hearing loss include congenital damage or malformations of the inner ear, tumor, trauma to the inner
ear, vascular disorders, ototoxic drugs, serious infections, and constant exposure to excessive levels of
sound or noise. Comparing and differentiating
between conductive and sensorineural hearing loss
can further be evaluated by performing hearing loss
tuning fork tests (see following section).
The test is performed on one ear at a time with
the audiometer, which delivers specific frequencies
of acoustic stimuli of specific intensities that determine a threshold (lowest intensity level) for each
frequency. Air conduction thresholds are obtained
using earphones; bone conduction thresholds are
determined by an oscillator placed in contact with
the head. The hearing loss is measured in decibels;
the acoustic powers required to obtain the thresholds are compared with the acoustic powers required
to obtain the same thresholds in one with normal
hearing. The results are recorded on a graph called
an audiogram, which plots the hearing threshold
levels in decibels (dB), with the frequencies between
125 or 250 to 8000 hertz (Hz).27
Hearing tests to estimate hearing ability can be
performed on infants and children using special
procedures, depending on the age of the client. This
can be performed as part of the general physical
assessment or as part of a screening program for
hearing deficit identification in the schools, or under

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include discontinuing the IV line and assessing the vital signs
and injection site.
Inform the client to resume any medications
withheld before the test.
Cholinergic/myasthenic crisis: Note and report
respiratory distress/muscle activity during
Tensilon administration. Provide resuscitation
equipment, oxygen, and tracheostomy supplies.
Administer ordered 0.5 to 1 mg of atropine IV for
cholinergic crisis or 0.5 to 2 mg neostigmine IV
for myasthenic crisis.

CHAPTER 24—Studies

both circumstances. In infants under 6 months of
age, normal reflexive responses can be observed
when sounds are administered with a handheld
device. In children between 6 months and 2 years of
age, minimal response levels can be determined by
behavioral responses to test tones. In children 2 years
of age and older, play audiometry that requires the
child to perform a task or raise a hand in response to
a specific tone is performed. In children 12 years of
age and older, response to speech of specific intensities, with the child following directions in identifying objects, can evaluate hearing loss affected by
speech frequencies.28 A simpler, faster screening test,
consisting of covering one ear and whispering in the
direction of the other ear from 1 to 2 feet away and
noting the response of the child, can also be used.
Presbycusis, also known as aging hearing loss, is a
sensorineural hearing loss that is part of the normal
aging process. It is a progressive decrease in acuity in
which high-frequency tones are affected more than
low-frequency tones. Various levels of deficit at
different ages can be experienced, with the incidence
higher in men than in women.
Reference Values
Normal pure tone average of 0 to 25 dB for
adults and 0 to 15 dB for children; ability to
detect 1 dB of increased intensity or loudness,
with the area of intelligible speech sounds
anywhere between 0 and 70 dB and a decrease in
hearing loss evident as the number increases; no
conductive, sensorineural, or mixed hearing loss
INTERFERING FACTORS

Obstruction of the ear canal by cerumen or other
material or object, which affects decibel perception
Noisy environment or extraneous movements
Tinnitus or other sensations, which can cause
inaccurate responses
Improper earphone fit or audiometer calibration
Inability or refusal of client to cooperate or follow
instructions
INDICATIONS FOR HEARING LOSS AUDIOMETRY

Screening for hearing loss in infants and children
and determining the need for a referral to an
audiologist
Determining the type and extent of hearing loss
(conductive as revealed by a reduced air threshold
and unchanged bone threshold, sensorineural as
revealed by a reduced air and bone threshold, or
mixed as evidenced by abnormal air and bone

of Specific Organs or Systems

597

thresholds) and determining whether further
radiologic, audiologic, or vestibular procedures
are needed to identify the cause
Evaluating the degree and extent of preoperative
and postoperative hearing loss after stapedectomy
in clients with otosclerosis
Evaluating communication disabilities and planning for rehabilitation interventions
Determining the need for and type of hearing aid
and evaluating its effectiveness
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test will be performed in a quiet room by
a nurse or an audiologist and that it takes about
20 minutes or less, depending on the test
That each ear will be tested separately by using
earphones through which tones of varying intensities are delivered, by using a device placed
behind the ear, or by using whispered sounds
spoken at a specific distance
That the client will be requested to press a button
at the time a tone is heard or to signal when a
whisper is heard
That no pain is associated with the test
Prepare for the procedure:
Obtain a history of known or suspected hearing
loss and cause; use of a hearing aid; complaints of
changes in auditory acuity; past auditory testing,
procedures, and results; and age of the client.
THE PROCEDURE

The client is placed in a sitting position in comfortable proximity of the audiometer in a soundproof
room. The audiometer is an electronic device that
delivers acoustic stimuli of specific frequencies at
specific intensities to determine hearing thresholds
for each frequency. An otoscopy examination is
performed to ensure that the external ear canal is
clear of any obstruction. Testing for closure of the
canal by the pressure of earphones is accomplished
by compressing the tragus. Tendency for the canal to
close (often the case in children and elderly clients)
can be corrected by the careful insertion of a small,
stiff plastic tube into the anterior canal. The
earphones are positioned on the head and over the
ear canals. A trial of a tone of 15 to 20 dB above the
expected threshold is delivered to an ear for 1 second
to familiarize the client with the sounds and to start
the test. The client is instructed to press the button
each time a tone is heard, no matter how loudly or
faintly it is perceived. The test results are plotted on
a graph called an audiogram using symbols that
indicate the ear tested and responses with earphones
(air conduction) or oscillator (bone conduction).

598

SECTION II—Diagnostic

Tests and Procedures

First, air conduction is tested by starting at 1000
Hz and gradually decreasing the intensity 10 dB at a
time until the client no longer presses the button,
indicating that the tone is no longer heard. The
intensity is then increased 5 dB at a time until the
tone is heard again. This process is repeated until the
same response is achieved two out of three times at
the same level. The threshold is derived from the
lowest decibel level that achieves a 50 percent
response rate. The test is continued for each ear, testing the better ear first, with tones delivered at 1000,
2000, 4000, and 8000 Hz, and then 1000, 500, and
250 Hz to determine a second threshold. Averaging
the air conduction thresholds at 500, 1000, and 2000
Hz reveals the degree of hearing loss. Tone averages
between 25 and 40 dB indicate a mild loss, 40 and
55 dB indicate a moderate loss, 56 and 90 dB indicate a moderately severe to severe loss, and over 90
dB indicates a profound or total loss.
Bone conduction is then tested by using an oscillator placed on the mastoid process behind the
ear(s) after removal of the earphones. The raised and
lowered tones are delivered as in air conduction,
using 250, 500, 1000, 2000, and 4000 Hz to determine the thresholds. An analysis of threshold
responses for air and bone conduction tones is made
to determine the type of hearing loss (conductive,
sensorineural, or mixed).29
A simpler test of hearing can be performed without the use of an audiometer but it is not as accurate
or as comprehensive in determining the type and
extent of hearing loss. It involves using a ticking
watch or whispering at a specific distance from each
ear. The ear not being tested is occluded with a
finger, and the tester stands at 15 ft from the client
and whispers or speaks words toward the ear to be
tested. If the words are not heard, the tester moves
closer, to 10 or 5 ft from the client. The second ear is
then tested in the same manner. The results are
recorded as 15/15 or 10/15, and so on. The test using
a ticking watch is similar except that the watch is
held next to the ear and then moved away from the
ear 1 ft at a time until the ticking is no longer heard.
The test is repeated for the second ear, and the
results are recorded at the distance when the ticking
is no longer heard.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after this test include
informing the client of the schedule for retesting
and instruction in the use, cleansing, and storing
of a hearing aid, if one is used.
Crossover tone: Note and report test tones that
cause crossover to the opposite ear during air
conduction testing (over 40 dB or 125 to 750 Hz,
50 dB or 1000 to 8000 Hz) or bone conduction

testing. Mask the ear that is not being tested.30
(Present a sound to the ear not being tested to
ensure that responses are based on hearing in the
ear being tested.)

HEARING LOSS TUNING FORK TESTS
Tuning fork tests are noninvasive assessment procedures that are used to distinguish conduction hearing loss from sensorineural hearing loss. They use a
tuning fork of 1024 Hz that is set into a light vibration with a tap on the handle. Three types of tuning
fork tests can be performed: the Weber test, the
Rinne test, and the Schwabach test. The Weber test is
performed to evaluate bone conduction deafness by
lateralizing the tuning fork tone to one ear.
Placement of the vibrating tuning fork on the head
stimulates the inner ears equally, and the boneconducted sound is heard more loudly and clearly
on the side with a conduction deficit. The Rinne test
is performed to compare air and bone conduction of
sound in both ears. Placement of the vibrating tines
near the external auditory meatus (air conduction)
and then placement of the stem on the mastoid
process (bone conduction) determines whether
conduction or sensorineural hearing loss is present.
If the sound is louder and longer at the mastoid
process than near the front of the ear, a conduction
hearing loss is identified. If a reduced sound in both
air and bone conduction is present, a sensorineural
hearing loss is identified. The Schwabach test is
performed by comparing the bone conduction of
the client with the normal bone conduction of the
examiner.31
The tuning fork tests are performed as a part of
the physical assessment examination and are
followed by hearing loss audiometry for confirmation of questionable or abnormal results.
INTERFERING FACTORS

Poor technique in striking the tuning fork or
incorrect placement
Inability of client to understand and cooperate in
identifying sites
Hearing loss in the examiner, which can affect
results in the Schwabach test
INDICATIONS FOR HEARING LOSS TUNING
FORK TESTS

Screening for hearing loss as part of a routine
physical examination and determining the need
for a referral to an audiologist
Obtaining information about the type of hearing
loss (conductive or sensorineural) as revealed by a
tone heard on one side, indicating a conductive
loss on that side or sensorineural loss on the other

CHAPTER 24—Studies

of Specific Organs or Systems

599

Reference Values
Normal air and bone conduction in both ears; no hearing loss
Weber test: Same tone loudness heard equally in both ears
Rinne test: Longer and louder tone heard by air conduction (40 seconds) than by bone
conduction (20 seconds)
Schwabach test: Same tone loudness heard equally long by the examiner and the client

side in the Weber test; bone conduction tone
heard louder or for a longer time than air conduction tone, indicating a conductive loss; or air
conduction tone heard louder, indicating a
sensorineural loss in the Rinne test; tone that is
heard longer by the client than by the examiner,
indicating a conductive loss, and heard for a
shorter time, indicating a sensorineural loss in the
Schwabach test
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test is conducted in a quiet room by
the nurse or the physician during a physical
or hearing examination and that it takes less than
5 minutes
That there are no restrictions or special preparations before the tests
That the client will be requested to respond
verbally or by pushing a button to indicate the
tones heard in each ear
That no pain is associated with these tests
Obtain a history of known or suspected hearing
loss and cause, use of hearing aid, changes in
auditory acuity, and other hearing tests and
procedures performed and the results.
THE PROCEDURE

The client is placed in a comfortable sitting position
facing the examiner in a chair or on the examining
table in a quiet environment. A tuning fork of 1024
Hz is used because it tests within the range of human
speech (400 to 5000 Hz).
Weber Test. Tap the tuning fork on the handle
against the hand to start a light vibration. Hold the
base of the vibrating tuning fork with the thumb and
forefinger of the dominant hand, and place it on the
middle of the forehead or at the vertex of the head.
Ask the client to determine whether the sound is
heard better and longer on one side than on the
other. Record as Weber right or left or, if the sound
is heard equally, as Weber negative.
Rinne Test. Tap the tuning fork on the handle
against the hand to start a light vibration. Have the

client move a finger in and out of the canal of the ear
not being tested (masking). Hold the base of the
vibrating tuning fork with the thumb and forefinger
of the dominant hand and place it in contact with
the mastoid process. Ask the client to indicate when
he or she can no longer hear the sound. Then place
the same vibrating tuning fork in front of the ear
canal without touching the external part of the ear.
Ask the client which of the two has the louder or
longer tone. Repeat the test in the other ear. Record
as Rinne positive if air conduction is heard longer
and as Rinne negative if bone conduction is heard
longer.
Schwabach Test. Tap the tuning fork on the handle
against the hand to start a light vibration. Hold the
base of the tuning fork against the client’s mastoid
process and ask whether the tone is heard. Have the
client mask the other ear by moving a finger in and
out of the ear not being tested. Then place the same
tuning fork against your own mastoid process of the
same side and listen for the tone. Continue to alternate the tuning fork until the sound is no longer
heard, and determine whether both cease to hear the
tone at the same time. Repeat the procedure on the
other ear. If the client hears the tone for a longer or
shorter time, count and note this in seconds.32
Abnormal test results require further testing by
audiometry to confirm findings and detect the type
and extent of hearing loss with more specificity.
NURSING CARE AFTER THE PROCEDURE

No special aftercare is required for this test.
Refer the client to an audiologist if a hearing loss
is detected.

ACOUSTIC ADMITTANCE TESTS
Acoustic admittance tests are procedures used to
measure the flow of sound into the ear (admittance)
and the resistance to that flow (impedance). Two
tests are included to measure acoustic admittance:
tympanometry testing, which measures the impedance of the middle ear to acoustic energy, and
acoustic reflexes testing, which measures admittance
change brought about by reflex contraction of the

600

SECTION II—Diagnostic

Tests and Procedures

stapedius muscle. Tympanometry is performed with
the use of a source of sound and a microphone that
is sealed in the external auditory canal. This instrument measures the acoustic energy that passes
through or is reflected by the middle ear. In conductive hearing loss, less sound passes through to the
middle ear, and more sound is reflected by the
middle ear. Middle ear compliance responds
normally to external ear pressure that is equal to
atmospheric pressure, and the increase or decrease
in the pressure results in various patterns of compliance. The measurement of compliance supplies the
diagnostic information needed to determine middle
ear abnormalities such as effusion or eustachian
tube pathological conditions. It also detects changes
in compliance that are produced by reflex contraction of the stapedius muscle to supply diagnostic
information about facial (seventh) nerve paralysis
by the presence or absence of the reflex and about
auditory (eighth) nerve adaptation or fatigue by the
presence or absence of the reflex adaptation or
decay in neural hearing loss.33 The results of the tests
are recorded and graphed on a tympanogram with
curves that are classified according to shape
(smooth, flat, peaked), amplitude (increased,
decreased, normal), and pressure (positive, negative, normal) and that are correlated with ear abnormalities.
These tests are easily performed on children and
older clients who are unable to cooperate during the
test, because voluntary participation is not required.
Those clients who do not respond voluntarily to
acoustic stimuli are candidates for electrocochleography, a test to measure cochlear response and
potentials of the auditory (eighth) nerve, or for
evoked response audiometry (see Chapter 23) to
measure responses from the brainstem and auditory
cortex.

Reference Values
Normal admittance responses by the tympanic
membrane and stapedius muscle; no hearing
loss; no middle ear or eustachian tube abnormalities; no lesions of the cochlear apparatus or
facial (seventh) or auditory (eighth) nerves
Tympanometry: Smooth and symmetrical
tympanogram with air pressure range of about
100 decapascals (daPa)
Acoustic reflexes: Trans-brainstem reflex threshold
of tones of 70 to 100 dB; ipsilateral thresholds
of 3–12 dB lower; reflex decay, no more than
half of the baseline over 10 seconds34

INTERFERING FACTORS

Probe that is incorrectly placed, clogged, or
moved or failure to obtain and maintain a seal of
the probe in the ear canal during the test
Equipment artifacts that can produce inaccurate
measurement of the admittance reflex stimuli,
which can affect acoustic reflexes testing
Client movement, talking, or swallowing
INDICATIONS FOR ACOUSTIC ADMITTANCE
TESTS

Diagnosing middle ear pathology such as acute
otitis media, tumor, or effusion as revealed by
changes in the shape, amplitude, and pressure
readings on the tympanogram
Determining tympanic membrane abnormalities
such as perforation, scarring, or tympanosclerosis
affecting auditory acuity, as revealed by large
changes in admittance
Determining or confirming the type of lesion in
conductive hearing loss, because the middle ear
absorbs less sound and reflects more sound in
tympanometry
Determining eustachian tube dysfunction caused
by obstruction or failure of the tube to open periodically, resulting in a negative air pressure in the
middle ear with an accumulation of effusion and
edema, as revealed by pressure and amplitude
changes and air pressure fluctuations, with respirations recorded in tympanometry
Determining ossicular chain discontinuity or
fusion causing conductive hearing loss that results
from disorders such as necrosis or dislocation of
the incus or stapedial footplate ankylosis, as
revealed by changes in admittance
Diagnosing facial (seventh) nerve paralysis, as
evidenced by compliance changes produced by
reflex contraction of the stapedius muscle
Differentiating among cochlear lesions or abnormalities of the cochlear apparatus (sensory) and
acoustic (eighth) nerve brainstem lesions (neural)
that cause sensorineural hearing loss by decreasing or distorting the transmission of information
to the brain, revealed by reflex adaptation or
decay in the acoustic reflex test
Differentiating between acoustic (eighth) nerve
and peripheral brainstem lesions from intra-axial
brainstem lesions as evidenced by ipsilateral and
brainstem determinations and changes in reflex
magnitude
Differentiating between sensory and neural hearing loss as revealed by the presence or absence of
reflex adaptation or decay below 2000 Hz
Determining or confirming the presence of

CHAPTER 24—Studies

pseudohypacusis as revealed by confirming
voluntary thresholds

of Specific Organs or Systems

601

Explain to the client:
That the tests are performed by the audiologist or
physician in a quiet room and that each test takes
less than 5 minutes
That there are no restrictions in food, fluid, or
activity before the tests
That the introduction of air pressure into the ear
can cause dizziness that should be reported but
that the dizziness disappears
That a probe is placed into the ear and that some
mild discomfort can be experienced at this time
That the tests do not harm the ears when the air
and sound stimuli are introduced
Prepare for the procedure:
Obtain a history of known or suspected hearing
loss and type and cause, ear conditions with treatment regimens, ear surgery procedures, and other
tests and procedures to assess and diagnose auditory deficit.

test or upon hearing the sounds. The air pressure is
changed, and the admittance is recorded manually
or on a strip chart with a recorder. At least six measurements are taken, more if needed to measure
extensive admittance changes. A tympanogram that
displays no admittance change requires evaluation
of probe placement or clogging and repetition of
the test.
The acoustic reflex test is performed by the introduction of a pure tone stimulus of 500 to 4000 Hz to
one ear via the probe. This stimulus causes a bilateral
reflex activation. Changes in admittance in the ear
receiving the stimulus (ipsilateral) or in the opposite
ear (trans-brainstem) are measured and recorded.
The reflex thresholds are determined by the introduction of the sound stimuli in increases of 10 dB
and then a decrease of 10 dB when the first reflex
occurs. This decrease is followed by increases of 5 dB
at a time, with recordings made at the lowest level of
stimulus at which a reflex is noted. The reflex decay
is then measured in the opposite ear at 500 to 1000
Hz; the sound stimulus is introduced at 10 dB above
the reflex threshold for 10 seconds. The reflex
magnitude at 5 or 10 seconds is compared with the
baseline taken at 1 second to determine reflex decay.
Abnormal reflex decay is concluded if the reflex
magnitude decreases to less than half of the baseline.35

THE PROCEDURE

NURSING CARE AFTER THE PROCEDURE

The client is placed in a sitting position (a child can
be held on the lap of the caregiver) in a quiet room.
An audiometer can be included in the equipment
needed for the test if acoustic reflexes are to be
tested. An otoscopy examination is performed to
ensure that the external ear canal is clear of any
obstruction. The appropriate probe cuff is selected
to fit the size and shape of the ear canal. This cuff
assists in maintaining a proper seal of the probe. The
calibrated probe tip is inserted into the ear canal
with the dominant hand while the nondominant
hand pulls the ear upward and backward (adult) or
downward (child). The probe tip is equipped with a
microphone. The probe is sealed to maintain a negative pressure of 200 daPa, and some silicone putty is
used to ensure the seal, if needed, to prevent possible
leaks that would cause inaccurate threshold results.
The calibrated probe contains an admittance meter,
electronic tone generator (sound source), and air
pressure manometer and pump used in the delivery
of sound and air pressure stimuli. The probe tone
level and meter sensitivity are set, and air pressure is
delivered to perform the tympanometry. The client
is requested to remain very still and to avoid any
movement of the face, mouth, and head during the

Care and assessment after these tests include removing the probe from the ear canal and gently cleansing and drying the canal.

CONTRAINDICATIONS

Recent surgical procedures on the middle ear to
treat chronic otitis media or to correct anatomic
abnormalities
NURSING CARE BEFORE THE PROCEDURE

OTONEUROLOGICAL TESTS
Otoneurological tests are noninvasive procedures
performed in the assessment of cerebellar or
vestibular function. They include the falling test,
past-pointing test, and Romberg test. The falling
test determines dysfunction affecting the entire
body through the performance of body maneuvers
with the eyes open and closed to note a swaying or
falling tendency. The past-pointing test determines
dysfunction through performance of finger pointing
with the eyes open and closed to note the ability and
direction of the past pointing.36 The Romberg test
determines static vestibular dysfunction through the
performance of body maneuvers with the eyes open
and closed to note arm drift and postural stability. It
is also performed as part of the neurological physical
examination to evaluate the muscle control of
balance and posture (inability to stand with the feet
together while the eyes are closed).
The vestibular receptive organs are located in the

602

SECTION II—Diagnostic

Tests and Procedures

inner ear and are connected to the CNS, both of
which contribute to the reflex activity needed in
maintaining body balance, posture, and movement.
These vestibular receptors involve nerve fibers that
travel in a portion of the acoustic (eighth) nerve
to the cerebellum via the medulla and pons.
Abnormalities of vestibular function are characterized by vertigo, tinnitus, and hearing loss. They can
include peripheral vestibular dysfunction such as
motion sickness or Ménière’s disease and trauma,
infection, or reaction to ototoxic drugs that cause
irritation or damage to the vestibular end organs or
nerves. Irritation or injury to the system can result in
balance disorders reflected by posture instability,
dystaxia, and falling. They also can also include
central vestibular dysfunction caused by cerebellar
tumor compression resulting in vertigo, nystagmus,
and dystaxia.37
Reference Values
Normal cerebellar and vestibular structure and
function; no dizziness, nystagmus, or balance
abnormalities
Falling test: Balance maintained with eyes open
and closed
Past-pointing test: Ability to touch examiner’s
index finger with own index finger with eyes
open and closed
Romberg test: Ability to stand with feet together
and eyes closed

INTERFERING FACTORS

Sedatives, antivertiginic agents, stimulants, or
depressants that act on the CNS
Alcohol intake before the test, which can affect
ability to maintain equilibrium and coordination
Inability of client to understand or perform the
body movements needed for the tests
INDICATIONS FOR OTONEUROLOGICAL TESTS

Dizziness, nystagmus, or equilibrium dysfunction
to determine the cause
Screening for neurological disorders as part of the
routine neurological physical examination
Identification of cerebellar or vestibular lesions
that affect movements of the entire body or the
upper body as revealed by swaying when the eyes
are open or closed or by swaying in the direction
opposite to nystagmus when the eyes are closed,
respectively

Evaluation of posture, balance, and ability to
coordinate movements in determining the extent
of neurological abnormalities
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the tests are performed by the nurse or
physician during the routine physical examination and that they take about 10 minutes
That there are no restrictions of food or fluids
before the tests
That the client is requested to open and close the
eyes and perform several movements with the
arms and legs during the tests
That no pain is associated with the tests
Prepare for the procedure:
Obtain a history of known or suspected neurological disorders, signs and symptoms that are related
to balance and coordination problems, alcohol
and medications taken, and neurological tests and
procedures and results.
THE PROCEDURE

The client is placed in a sitting position or stands
and faces the examiner, depending on the test. The
examiner should stand near the client to hold or
catch the client if he or she sways or falls.
Falling Test. Request that the client stand with the
arms at the sides and perform the following activities: Stand with the feet together for 20 seconds with
eyes open and closed, stand on one foot and then the
other for 5 seconds with the eyes open and closed,
stand with heel to toe for 20 seconds with eyes open
and closed, and walk both forward and backward
with the eyes open and closed. Inform the client that
he or she will not be allowed to fall. Note and record
any swaying or falling by the client, the direction,
and closed or open eyes.
Past-Pointing Test. Request that the client sit in a
chair. Hold an index finger out and request that the
client touch it with the right index finger with the
eyes open. Have the client then lower the arm and
touch the finger again with the eyes closed. Repeat
the procedure using the client’s left index finger.
Note and record any past pointing, the direction, the
side of the finger used, and open or closed eyes.
Romberg Test. Request that the client stand with
the feet together with the eyes closed for 20 seconds,
and note any swaying or falling and the direction.
NURSING CARE AFTER THE PROCEDURE

No special aftercare or assessment activities are
required for these tests.

CHAPTER 24—Studies

of Specific Organs or Systems

603

Reference Values
Normal auditory system and sensorineural hearing; no lesions of the cochlear apparatus, acoustic (eighth)
nerve, or auditory pathways to the brain
Békésy audiometry: Pulsed and continuous tones overlap on the tracings
Tone decay: Tone perceived at 0–10 dB above threshold for 1 min
Binaural loudness balance: Two sounds perceived as being of equal loudness when presented in equal intensity
Binaural midplane localization: One tone heard at the center of the head when two tones of equal intensities are presented
Masking level differences: A threshold difference of 12 dB between homophasic and antiphasic conditions
Auditory brainstem electric response: Acoustic nerve and upper brainstem response wave tracings that
follow the same pattern
Trauma from a fall: Stand close to the client if he
or she has complained of dizziness. Enlist a
second person to help if the client is obese, tall, or
disoriented.

OTONEURAL LESION SITE TESTS
Otoneural lesion site tests are procedures performed
to localize the site of lesions and to determine the
extent of damage to the auditory system. These tests
are usually performed when hearing loss audiometry, admittance tests, and presenting signs and symptoms indicate sensorineural hearing loss. They assist
in differentiating between sensory (cochlear) and
neural (acoustic nerve) hearing loss. A battery of
tests is administered that includes Békésy automatic
audiometry, tone decay, binaural loudness balance
and midplane localization, masking level differences,
speech discrimination, and auditory brainstem electric response. Site-of-lesion tests use earphones to
present tones of varying intensities that are distinguished from the sensation level. The intensity is the
hearing level, and the sensation level is the number
of decibels above the threshold for a specific tone.
Depending on the test performed, lesions of the
cochlear nerve, retrocochlear system, and brainstem
and lesions or damage to the cortex, any of which
affect hearing acuity, can be located.38
INTERFERING FACTORS

Improper electrode placement or poor equipment
function
Inability of client to understand or cooperate
during the test
Severe hearing impairment, which can affect the
ability of the client to participate in the tests when
tones are presented and responses are expected

INDICATIONS FOR OTONEURAL LESION SITE
TESTS

Dizziness, tinnitus, hearing loss, and other neurological complaints to determine whether they are
caused by sensorineural hearing function
Determination of the presence and location of
lesion sites when conductive hearing loss has been
previously tested and ruled out
Differentiation between sensory (cochlear) and
neural (acoustic nerve) hearing loss; differentiation between cochlear and retrocochlear hearing
loss; location of lesions of the retrocochlear
system at the acoustic nerve that can be extraaxial or intra-axial brainstem or cortex lesions
Determination of the presence, site, and effects of
neural lesions of the auditory system
Diagnosis of Ménière’s disease as revealed by
sensory hearing loss
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the tests are performed by an audiologist in
a quiet specially equipped room and that they take
up to 90 minutes, depending on the number of
tests to be conducted
That there are no restrictions in foods or fluids or
special preparation before the tests
That each ear can be tested individually and that
earphones are used to transmit sounds that the
client responds to verbally or by pushing a button
That no pain is associated with the tests
Prepare for the procedure:
Obtain a history of known or suspected hearing
loss and cause; signs and symptoms associated
with the auditory system; and past auditory tests,
procedures, and results.

604

SECTION II—Diagnostic

Tests and Procedures

THE PROCEDURE

The client is placed in a quiet environment in a
sitting position. The earphones are placed on the
head and secured over both ears.
Békésy Audiometry. The audiometer is set to
record at the desired frequencies (one or across all of
them, from 100 to 10,000 Hz). The threshold for a
pulsing tone and a continuous tone is determined
for this test. The client is requested to control the
intensity by pressing a response button every time a
tone is heard until the tone is no longer heard and
then releasing the button. This procedure causes the
tone intensity to increase and allows the client to
trace back and forth across his or her threshold. The
procedure is repeated for 5 minutes and can be
increased gradually from 100 to 10,000 Hz. The tracings of the frequencies (broken for the pulsed tone
and solid for the continuous tone) are recorded on
an audiogram. Tracings reveal movements above
and below the client’s threshold, and the types of
curves on the tracing identify the type of auditory
lesions as follows:
Type I: Normal overlapping tracings in which
continuous and interrupted tracings are superimposed
Type II: Superimposed tracings up to 1000 Hz
with a separation of tracings of 20 dB above
this frequency, indicative of cochlear loss or
Ménière’s disease
Type III: Separation of the tracings at lower
frequencies and decline in the threshold for the
continuous tone, indicative of retrocochlear
pathology (neural lesions such as acoustic
neurinoma)
Type IV: Separation of the tracings at all frequencies, indicative of active severe cochlear lesions
or early neural lesions
Type V: Separation of the tracings with the
threshold of the interrupted tracings greater
than the threshold for continuous tracings,
indicative of psychogenic hearing loss39
Tone Decay Test. A tone is presented at the client’s
threshold and the client is requested to identify the
time at which the tone is audible through the
earphones. Tones are increased 5 dB if sounds are
inaudible so that a tone can be heard again. The tone
is repeated until it is heard continuously for a
minute to determine the presence of pathological
adaptation that is mildly abnormal in sensory
lesions and severely abnormal in neural lesions. In
cochlear or retrocochlear lesions a tone is lower or
higher than the threshold, respectively.
Binaural Loudness Balance. A tone is presented to

one ear and then the other; the tone at one ear is
kept at a constant intensity of 90 dB, and then a
varied tone is used in the other. The client is
requested to respond when the tones sound the same
in both ears. This procedure differentiates between
cochlear and retrocochlear lesions by the presence of
recruitment (abnormal increase in the perception of
loudness or hearing of sounds despite a hearing loss)
or absence of recruitment, respectively.
Binaural Midplane Localization. A tone is
presented to one ear at 90 dB while tones of varied
intensities are presented to the other ear. The client
is requested to indicate when a single tone is heard at
the center of the head. This procedure differentiates
between cochlear and retrocochlear lesions by hearing a centered sound or never hearing the centered
sound, respectively.
Masking Level Differences. A tone of 500 Hz and a
masking noise are presented to both ears at a
constant intensity, and the threshold is determined.
This determination is followed by a change that
cannot be heard by either ear individually to establish another threshold level. This procedure determines acoustic nerve or brainstem lesion if no
change is noted at different threshold levels.
Auditory Brainstem Electric Response. Electrodes
are placed at the scalp vertex, and the mastoid
process of one ear is tested and then the other.
The stimuli are presented in rapid tone times of
1 millisecond at 10 per second until a desired
number of responses are recorded. The responses are
recorded as waves at 1-millisecond intervals at
different intensities. Cochlear and retrocochlear
lesions are differentiated by normal responses at
high intensities or by absent or late responses at high
intensities, respectively.40
NURSING CARE AFTER THE PROCEDURE

Care after these tests includes removing the
devices from the head.

SPONDEE SPEECH RECEPTION
THRESHOLD TEST
The spondee speech reception threshold test is a
noninvasive speech audiometry procedure used to
measure hearing loss related to speech. The intensity
at which speech is recognized is determined by
presenting a list of spondee words, which are familiar words containing two syllables equally accented,
for example, baseball, birthday, and railroad. The test
represents hearing levels at speech frequencies of
500, 1000, and 2000 Hz. The words are presented at
specific intensities, and the intensity at which a client

CHAPTER 24—Studies

repeats 50 percent of the words correctly reveals the
test results. Word recognition tests can also be used
to assist in diagnosing high-frequency hearing loss.
Those with this type of hearing loss miss consonant
sounds that affect the understanding of speech. The
test involves the ability to recognize and repeat
words such as pin, din, bin, and sin that are distinguished by consonants and that are presented at a
level above the spondee threshold. Word recognition
ability is a different type of hearing loss than that
diagnosed by audiometry.41
Reference Values
Normal spondee threshold of about 10 dB of the
pure tone threshold with 50 percent of the
presented words correctly repeated at an appropriate intensity; normal speech recognition with
90 to 100 percent of the presented words
correctly repeated at an appropriate intensity
INTERFERING FACTORS

Client lack of familiarity with the language the
words are presented in or with the words themselves
Improper placement of the earphones and inconsistency in frequency of word presentation

of Specific Organs or Systems

605

other hearing tests, and determine ability to
understand English words and sounds.
THE PROCEDURE

The client is seated on a chair in a soundproof
booth. The earphones are placed on the head and
secured over the ears, and the audiometer is set at 20
dB above the known pure tone threshold obtained
from audiometry (see “Hearing Loss Audiometry”
section). The client is introduced to the list of
spondee words (two-syllable words) to be used in
the test, for example, baseball or staircase, but the list
is not used by the client during the test. The spondee
words are presented to the ear with the best auditory
acuity, first via a speech audiometer with the intensity decreased. The intensity is then increased to the
softest sound at which the client is able to hear the
words and to respond correctly to 50 percent of
them. The procedure is repeated for the other ear.
Speech discrimination is tested by presenting a
list of 50 phonetically balanced words such as pin,
bin, and kin at an intensity of 40 dB above the
spondee reception threshold. A score is determined
from the number of responses. A normal score of 90
to 100 percent indicates a conductive hearing loss,
and a reduced score indicates sensorineural hearing
loss and acoustic (eighth) nerve impairment.42
NURSING CARE AFTER THE PROCEDURE

INDICATIONS FOR SPONDEE SPEECH RECEPTION
THRESHOLD TEST

Determining the extent of hearing loss related to
speech recognition as revealed by the faintest level
at which the spondee words are correctly repeated
Differentiating a real hearing loss from pseudohypacusis
Evaluating clarity of speech sounds or speech
discrimination as revealed by word recognition at
40 dB above the spondee threshold
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test is performed by an audiologist in a
specially equipped soundproof booth and that it
takes about 5 to 10 minutes
That there are no food or fluid restrictions before
the test
That a series of words that change from loud to
soft tones will be presented via earphones and that
the client will be requested to repeat them
That each ear is tested separately
That no pain is associated with the test
Prepare for the procedure:
Obtain a history of known or suspected hearing
disorders and results of pure tone audiometry and

No special aftercare or assessment activities are
required for this test.

VISUAL ACUITY TESTS
Visual acuity tests are noninvasive procedures
performed to evaluate the ability to see and to
perceive details. They include the Snellen test, which
uses an eye chart to determine distance visual acuity,
and the Jaeger test, which uses a card to determine
near visual acuity. Both eyes are always tested individually with and without corrective lenses, and the
scores are recorded for each eye. Visual acuity that
cannot be quantitated by these tests should be tested
and noted by the ability of the client to count
fingers, detect hand movements, or distinguish light.
Visual changes can occur as manifestations of conditions such as lesions or atrophy of the optic (second)
nerve, eyelid muscle abnormalities and ptosis,
conjunctivitis, trauma or abrasions of the cornea or
keratitis, changes in intraocular pressure, cataract,
retinal abnormalities or defects, and neurological
conditions.
The Snellen test is the most common test and
uses a standardized eye chart that consists of lines of
block letters that are graded from the largest letters

606

SECTION II—Diagnostic

Tests and Procedures

at the top line to the smallest at the bottom line. It
tests visual acuity of each eye by the client’s ability to
read the letters on a chart that is hung on a wall at a
distance of 20 ft. Each line has a number that indicates the distance in feet at which an average person
can read 50 percent of the letters correctly. The score
is derived from this number and the distance and is
recorded as a fraction, with the distance (20 ft) over
(/) the number of the smallest line read. For example, 20/30 is the distance of 20 ft, and 30 is the
number at the lowest line read. A minus number can
be added to indicate errors made in reading the
numbers on that line, for example, 20/30 – 2. The
lower the line of numbers that can be read, the better
the visual acuity. The chart numbers can be replaced
by figures or other symbols for children and clients
who cannot read.
The Jaeger test uses a standardized card that
consists of reading material in print that is graded
from large to small. Each eye is tested for its ability
to read the print while the card is held at a specific
distance. Print size is identified based on the ability
of a person with normal sight to read the card while
it is held at a specific distance. The smallest size of
print and the nearest distance for reading the print
are noted as a fraction, with the distance of 14
inches/print size able to be read at that distance. This
test is usually reserved for those over 40 years of age
who have difficulty reading.43 Visual acuity tests are
performed as part of the general physical examination with or without the presence of visual
complaints.
Presbyopia is the diminished visual acuity experienced in older people as part of the normal aging
process. Presbyopia results in the thickening of the
lens, causing its fibers to become less elastic and
affecting the range of focus and accommodation.
Reference Values
Normal distance visual acuity of 20/20 and near
visual acuity of 14/14
INTERFERING FACTORS

Inability of client to cooperate and participate in
the tests
Inability of client to recognize and identify the
letters or words on the chart or card
Failure of client to bring corrective lenses to be
used for testing the corrected vision during the
test
INDICATIONS FOR VISUAL ACUITY TESTS

Screening for impaired visual acuity in children

with no complaints and determination of the
need for a referral to an ophthalmologist
Screening for presbyopia and near vision impairment in clients over 40 years of age, with or without complaints, to determine the need for a
referral
Eye strain, blurring, difficulty in reading, or other
complaints to determine whether the cause is
related to visual acuity
Determination of the type of visual impairment,
distance or near visual acuity deficit, and the need
for corrective lenses
Evaluation of existing visual correction for change
in prescription lenses
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the tests are performed by a physician, technician, or nurse and that they take 5 to 10 minutes
That the client should bring corrective glasses or
contact lenses to the test for evaluation
That there are no food or fluid restrictions before
the tests
That each eye is tested separately with and without the corrective lenses
That the client is requested to read letters or
symbols of different sizes on a chart or words of
different-sized print on a card to test vision
That no pain is associated with the tests
Prepare for the procedure:
Obtain a history of known or suspected visual
impairment and cause, use of corrective lenses,
and age of client.
THE PROCEDURE

The client is seated 20 ft away from the Snellen chart
to test distance visual acuity. If the client wears
glasses or contact lenses, he or she is requested to
remove them to first test the vision without correction. The client is requested to occlude the left eye
with a handheld occluder, or the eye is occluded with
an eye patch if the client is unable to hold the device
to test the right eye. The client is then requested to
read the line on the chart with the smallest letters or
symbols, which is recorded as the denominator of
the fraction, with the numerator indicating the
distance of 20 ft. The number of errors on the line
with the smallest letters or symbols read can be
recorded as a minus next to the denominator, that is,
20/20 – 1. The test is then repeated on the left eye by
occluding the right eye. If the client wears corrective
lenses, the same tests are performed on the right and
left eyes with the corrective lenses in place to test the
effectiveness of the lenses and to determine whether
further correction is needed. A pinhole test can be

CHAPTER 24—Studies

performed if the vision is less than the normal 20/20
to determine whether the abnormal acuity is caused
by a refractive error or an organic disorder. The test
is conducted by asking the client to look through a
pinhole in a card when reading the chart. If vision
cannot be quantitated by this test, the client can be
requested to count fingers at different distances or to
distinguish light by penlight or room light.
Clients who are unable to read the large E at the
top of the chart can be tested by asking them to walk
toward the chart and stop at the distance at which
the E can be visualized. This is recorded as the
distance in feet and the line of the large E, that is,
20/200.
The client is seated to read the Jaeger card held at
a usual reading distance to test near visual acuity (14
inches). Both eyes are tested as in the Snellen chart
without and then with corrective lenses. The results
are recorded with the distance as the numerator
and the distance needed by those with normal vision
to read the same print at a specific distance as
the denominator, that is, 14/14 for normal vision
and a larger denominator indicating reduced near
vision.44
NURSING CARE AFTER THE PROCEDURE

No special aftercare or assessment activities are
required for these tests.

VISUAL FIELD TESTS
Visual field tests are noninvasive procedures
performed to detect and locate lesions that cause
major defects in the visual fields. These defects occur
as a result of damage to the visual pathways or the
visual cortex. Tests include perimetry, which records
the total extent of the visual field; tangent screen,
which records the central visual field from a fixed
point; and the confrontation test, which is a simple
method to screen the visual field in those who are
not candidates for the other tests. Confrontation
testing is also performed as a part of the routine
neurological physical examination to determine
gross abnormalities that, if a defect is detected,
should be followed by perimetric or tangent screen
testing.45 Disorders that can interrupt the visual
pathways include trauma, tumors, and vascular
lesions. Disorders of the visual cortex include
damage or pathology in the binocular portion of the
primary visual cortex.
The visual field comprises the areas that are visible during the fixation of vision in one direction.
The complete visual field is seen by both eyes (binocular) and is divided into the central and peripheral
sections. The central section provides the highest

of Specific Organs or Systems

607

visual acuity and focuses on the central fovea,
whereas the peripheral section provides the ability to
detect objects, stationary or moving. The right and
left periphery of the visual field, which is beyond the
visual field shared by both eyes, reflects the side of
the retina on which the images are seen. When the
image reaches the retinas, the visual information is
carried to the brain by the optic (second) nerve,
which extends from the back of the optic globe
through the orbit and optic foramen to the base of
the brain. The two optic nerves fuse at the optic
chiasm, and the optic tracts contain fibers from both
eyes that transmit information from the same visual
field. The primary visual cortex is located in the
occipital lobe of the brain and functions to add
meaning to visual perception, based on past experiences. The circuitry in this area contains specific
neurons that respond to shapes, colors, and moving
edges of an inclination. Its organization allows separate and multiple representations of a visual field.
Retinal defects also cause visual field defects.
Normally, a hole, or scotoma, is present in the visual
field because the optic nerve does not contain
photoreceptors and the corresponding location in
the visual field becomes a blind spot. Retinal damage
caused by localized pathology or vascular accidents
can produce additional blind spots. The absence of
vision in the center of the bilateral visual field is
annoying and can be dangerous because part of the
visual field disappears, depending on the location of
the fixation point.46 The Amsler grid test is
performed to screen for the detection of central
scotomas when abnormal vision is present and
macular pathology is suspected as the cause. It
involves the viewing of squares on a grid with a black
dot in the center and evaluating vision for any blurring, distortion, or inability to see the dot.
INTERFERING FACTORS

Severely impaired visual acuity that prevents
perception of the moving object within the field
Inability of client to understand or cooperate with
the instructions given during the test
INDICATIONS FOR VISUAL FIELD TESTS

Assessing the monocular vision field of each eye
to detect abnormalities as part of the routine
neurological examination
Identifying central and peripheral visual field
defects to determine lesion sites in the retina,
optic pathways, and visual cortex
Evaluating the progression or resolution of ocular
disorders such as glaucoma, tumors, trauma,
vascular insufficiency, and neurological disorders
such as cerebrovascular accident or brain tumor

608

SECTION II—Diagnostic

Tests and Procedures

Reference Values
Normal visual field perception in both eyes; no lesions of the visual pathways or visual cortex
Confrontation test: Correct visualization by each eye of an object moving from the center to the periphery
and from the periphery to the center and into four visual quadrants while the client’s eye is fixated on
the examiner’s eye
Tangent screen test: Ability of each eye to visualize an object within the entire central visual field circle, with
detection of the blind spot in its correct position in relation to the central fixation point
Perimetry: Visualization by each eye of different-sized test objects as they are moved in all areas of the
visual field and disappear and reappear normally at appropriate degrees within the field

NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Visual Acuity Tests”
section.
Inform the client that the test takes 30 minutes.
Obtain a history of known or suspected eye or
neurological disorders, change in visual acuity,
treatment regimens, and other tests and procedures performed and the results.
THE PROCEDURE

The client is placed in a comfortable sitting position.
Confrontation Test. This test is commonly
performed as a part of the routine neurological
exam to detect major or large defects in the visual
fields. The examiner sits or stands 2 to 3 ft directly in
front of the client. The client is requested to cover or
close one eye and focus the other eye on the examiner’s eye. The examiner slowly moves a finger from
the periphery toward the center and from the center
toward the periphery through the vertical, horizontal, and oblique areas of the field. The client is
requested to respond when the finger becomes visible during each movement. The test is then repeated
for the other eye.
Tangent Screen Test. A black screen is placed about
3 ft in front of the client. One eye is covered, and the
client is requested to fixate the other eye on a target
site on the screen. A test object at the tip of a wand
is moved out along the meridians from the central
fixation point to 30 degrees. The size of the test
object is determined by the client’s visual acuity. The
client is requested to respond when the test object
appears, and the responses are plotted on the screen.
The other eye is then covered and the test is
repeated. Test objects of various sizes and colors can
also be used to outline the field and identify the
presence of small holes (scotomas). Results are
determined and recorded by comparing the defect
with the various sizes of the test objects and the
distance between the client and the screen.

Perimetric Test. The client is seated and the head is
stabilized by a chin rest while one eye is occluded
and the other eye is fixated on a central point
directly in front of the eye. A small dot, light, or
colored object is moved back and forth in all areas of
the visual field. The client is requested to respond to
the visibility and color of the object and to signal
when the object disappears. Test objects of various
sizes are used. The arc is rotated, and another meridian is checked. Standardized movements of the test
object are made at 30-degree or lesser intervals to
identify the defect. The opposite eye is occluded, and
the test is repeated on the other eye. The results are
recorded from the plotting on a circular chart of
the visual field perceptions with radii at 30-degree
intervals.47
NURSING CARE AFTER THE PROCEDURE

No special aftercare or assessment activities are
required for this test.

COLOR PERCEPTION TESTS
Color perception tests are performed to determine
the acuity for color discrimination that is most
commonly partial but that can be complete. Deficits
can be genetic and result from the defective function
of one or more of the three cone color systems (blue,
green, red), or the deficits can be acquired and result
from outer (red, green) or inner (blue) retinal layer
pathology. The most common test performed for
color discrimination defects uses pseudoisochromatic plates with numbers or letters buried in a
matrix of colored dots. Color blindness is determined by the client’s misreading of the numbers or
letters.
The photoreceptors on the retina include rods,
which discriminate black and white, and cones,
which discriminate color. The cone receptors are
sensitive to different wavelengths of light, which
provide for color vision. Three types of cones
respond to the red, blue, and green spectrums,

CHAPTER 24—Studies

depending on the presence of one or more of the
color-sensitive molecules that are bound by the
visual pigment substance. The amount of involvement of each cone color system determines the hue
of a color, and the amount of light received determines the brightness of each hue.48
Color perception tests to determine the presence
of a deficiency can be part of a routine eye examination or can be initiated after a complaint of difficulty
in discriminating between a red and a green traffic
light or becoming aware of wearing the wrong
combination of colors. Additional tests of retinal
function can be performed to determine the extent
of an identified deficiency.
Reference Values
Normal visual color discrimination, no difficulty in the identification of color combinations
INTERFERING FACTORS

Inability of client to read
Poor visual acuity, failure to wear corrective
lenses, poor lighting, or anything that affects the
ability to see the test plate
Inability of client to cooperate and participate in
the test
Plates that are discolored or damaged
INDICATIONS FOR COLOR PERCEPTION TESTS

Detection of deficiencies in color perception
Suspected retinal pathology affecting the cones
that are responsible for color discrimination
Family history of color visual deficit, because the
deficiency can be inherited
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Visual Acuity Tests”
section.
Obtain a history of known or suspected color
visual impairment in client or family members,
importance of color discrimination in work life,
or use of corrective lenses.
THE PROCEDURE

The client is placed in a sitting position. One eye is
covered, and a test book containing pseudoisochromatic plates is held about 12 to 14 inches from the
exposed eye. An object that can be used to point is
given to the client. Acquaint the client with the plates
and the patterns and symbols that will be shown.
Advise the client that he or she will be requested to
identify the numbers or letters that are buried in a

of Specific Organs or Systems

609

matrix of colored dots or to trace patterns or
symbols with the pointed object. As the test is given,
record the client responses as the numbers or letters
are misread or the patterns are not traced correctly.
Repeat the same test on the other eye.
NURSING CARE AFTER THE PROCEDURE

No special aftercare or assessment activities are
required for this test.

TONOMETRY
Tonometry is a noninvasive procedure performed to
indirectly measure intraocular pressure to assist in
diagnosing glaucoma. Secretion of aqueous humor
is continuous, regardless of the pressure of secreted
fluid and the rate of production, and it is normally
equal to the rate of drainage. An increased intraocular pressure results from an interference with the
drainage of the fluid anywhere along the outflow
pathway. Glaucoma is a group of eye conditions
characterized by a rise in intraocular pressure, which
can result in a progressive loss of peripheral vision;
later loss of central vision; and, finally, blindness, if
left untreated. It can be closed-angle or open-angle
glaucoma, depending on the location of the fluid
circulation and absorption. It can occur as a primary
disease or in association with other conditions of the
eye such as inflammation and infection, tumors, or
trauma.
Tonometry is performed with an instrument
called a tonometer. One type of tonometer (Schiøtz)
is placed directly on the anesthetized eye and measures the pressure by the corneal deformation
produced by force applied against it. The instrument
consists of a plate that rests on the cornea and has a
plunger-type apparatus that can apply pressure with
an indicator to measure the ocular pressure. Another
type is a noncontact tonometer that is mounted on a
slit lamp and measures the time needed to flatten an
anesthetized area of the cornea with an air blast. The
intraocular pressure is read on a dial as the complete
flattening is measured electronically. This method is
performed by a physician during routine slit-lamp
examinations.
Other procedures performed to detect glaucoma
are ophthalmoscopy, perimetry, and gonioscopy.
Reference Values
Normal intraocular pressure of 12 to 20 mm Hg,
depending on the time of day
INTERFERING FACTORS

Corneal surface that inhibits correct placement of

610

SECTION II—Diagnostic

Tests and Procedures

the tonometer footplate, which can alter measurement
Flaccid or rigid cornea that prevents proper
indentation of the tonometer footplate, which can
affect correct measurement
Inability of client to cooperate and remain quiet
during the test
Improper technique in the use of the tonometer
in performing the measurement
INDICATIONS FOR TONOMETRY

Screening for glaucoma in clients over the age
of 40
Measuring intraocular pressure to assist in the
diagnosis of glaucoma or determining whether
other tests should be performed to confirm the
diagnosis
Monitoring the progression of glaucoma and
effectiveness of the treatment regimen
CONTRAINDICATIONS

Corneal ulceration or infection that could cause
further damage
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test is performed by the physician and
takes about 1 to 2 minutes
That eyedrops are administered to anesthetize the
eyes and that no pain is associated with the test
That corrective lenses (glasses or contacts) are
removed before the test and that contacts are not
reinserted for 2 hours after the test
Prepare for the procedure:
Obtain a history of known or suspected ocular
disorders, changes in visual acuity, eye pain, and
other visual tests and procedures performed and
the results.
THE PROCEDURE

The client is placed in a supine position on the
examining table and informed of the importance of
lying very still. Ask the client to avoid blinking or
tightly closing the eyelids during the test. Instill 1
drop of the topical eye anesthetic in each eye, and
request that the client close the eyes to spread the
medication over the sclerae. Check the tonometer
for a zero reading and a freely moving plunger, and
prepare the instrument to measure the pressure
using 5.5 g of weight. Instruct the client to look at a
spot on the ceiling and to breathe normally. Gently
hold the lids of one eye with the thumb and forefinger of the nondominant hand without touching the
eyelashes. While holding the tonometer upright with
the thumb and forefinger of the dominant hand,

place the footplate of the instrument on the apex of
the cornea. Avoid any pressure on the cornea by the
fingers or any movement of the tonometer, which
can cause abrasions. Observe the needle on the calibrated part of the tonometer for a pulsating movement. Record the reading on the scale part of the
instrument and the time of day that the procedure
was performed. A reading of less than 4 requires that
additional weight (7.5 g or more) be applied to
obtain a measurement of intraocular pressure.
Repeat the procedure to measure the pressure of the
other eye.49
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include informing the client not to rub the eyes for 30 minutes or
to reinsert contact lenses for 2 hours after the
procedure until the anesthetic has had time to
wear off.
Inform the client that any scratchy feeling is
caused by tonometer movement during the test
and that this feeling disappears within 24 hours.
Corneal abrasion: Note and report complaints of
scratchy sensation. Hold tonometer still during
the test. Avoid touching the eyelashes, which can
cause blinking. Promote relaxation to prevent
movement during the procedure. Apply an eye
pad for comfort and protection, if needed.

REFRACTION
Refraction is a noninvasive procedure that tests the
visual acuity of eyes and determines any abnormalities or refractive errors that need correction. Visual
defects such as hyperopia (farsightedness), in which
the point of focus lies behind the retina; myopia
(nearsightedness), in which the point of focus lies in
front of the retina; and astigmatism, in which the
refraction is unequal in different curvatures of the
eyeball, can be corrected by glasses or contact lenses
after this examination. Hyperopia requires a convex
lens for correction, myopia requires a concave lens,
and astigmatism requires a cylindrical lens.50
Usually, pupils are dilated with eyedrops and the
eyes are examined with a retinoscope initially to
view the brightness, uniformity, and clarity of the
light reflection from the instrument. This examination is followed by trying lenses of different powers
as the client reads the lines on a Snellen chart to
determine the optimal lens to correct the deficit and
ensure visual acuity.
This test can be performed during any eye examination, but it is most likely to be performed on
those who already wear corrective lenses or
complain of a decrease in visual acuity.

CHAPTER 24—Studies

Reference Values
Normal refractive power of 44 diopters (distance
from the surface at which the rays come into
focus, measured in meters) in the cornea and
aqueous humor, 10 to 14 diopters in the lens,
and overall refractive power of the eye at 58
diopters; no evidence of refractive error51
INTERFERING FACTORS

Improper pupil dilation, which prevents adequate
examination for refractive error
Inability of client to remain still and cooperate
during the test
INDICATIONS FOR REFRACTION

Diagnosing refractive errors in vision
Determining whether an optical defect is present
and whether light rays entering the eye focus
correctly on the retina (emmetropia), whether the
point of focus is behind the retina (hyperopia or
farsightedness), whether the point of focus is in
front of the retina (myopia or nearsightedness), or
whether a nonuniform curvature of the horizontal plane is in contrast with the vertical plane
(astigmatism)
Determining the type of corrective lenses needed
for refractive errors, that is, biconvex or plus lenses
for hyperopia, biconcave or minus lenses for
myopia, or compensatory lenses for astigmatism
CONTRAINDICATIONS

Pupil dilation in clients with narrow-angle glaucoma
Allergies to medication (mydriatics) used for
pupil dilation
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the examination is performed by a physician
in a darkened room and that it takes about 15 to
20 minutes
That eyedrops are administered before the test to
dilate the pupils for better viewing of the eyes
That the client is requested to look straight ahead
while the eyes are examined with an instrument
and while different lenses are tried so that the best
corrective lenses can be prescribed
That there is no pain associated with this examination
Prepare for the procedure:
Administer an ordered mydriatic, 1 drop of 5
percent phenylephrine, to each eye, and repeat in
5 to 15 minutes to achieve pupil dilation.

of Specific Organs or Systems

611

Obtain a history of known or suspected visual
impairment, changes in visual acuity, use of
glasses or contact lenses, other tests and procedures performed to diagnose eye conditions needing corrective lenses, and results.
THE PROCEDURE

The client is placed in a sitting position in the examination chair and the examiner is seated about 2 ft
away at eye level with the client. The room light is
dimmed, and the retinoscope light is held in the
examiner’s hand in front of the client’s eyes and
directed through the dilated pupil. Each eye is examined for the characteristics of the red reflex, which
should normally move in the same direction as the
light. Lenses of differing strengths are then tried on
each eye as the client is requested to read the letters
on a Snellen chart posted on a wall 20 ft away. When
optimal visual acuity is obtained with the trial lenses
in each eye, a prescription for corrective lenses is
written.
NURSING CARE AFTER THE PROCEDURE

No special aftercare or assessment activities are
required after this examination.
Inform the client that some visual blurring from
the dilating medication can be experienced for
about 2 hours.

SLIT-LAMP BIOMICROSCOPY
Slit-lamp biomicroscopy is a noninvasive procedure
that allows visualization of the anterior portion of
the eye and its parts, that is, eyelid and eyelashes,
sclera, conjunctiva, cornea, iris, lens, and anterior
chamber, to detect pathology of any of these areas.
The slit lamp has a binocular microscope and light
source that can be adjusted to examine the fluid,
tissues, and structures of the eyes. Special attachments to the slit lamp are used for special studies
and more detailed views of specific areas.52
Reference Values
Normal anterior tissues and structures of the
eyes; no corneal, iridic, conjunctival, lens, tearing, or eyelid and eyelash pathology
INTERFERING FACTORS

Inability of client to cooperate during the examination
Improper administration of mydriatics
INDICATIONS FOR SLIT-LAMP BIOMICROSCOPY

Detection of corneal abrasions, ulcers, or abnor-

612

SECTION II—Diagnostic

Tests and Procedures

mal curvatures (keratoconus) before performing
a corneal staining procedure
Detection of lens opacities indicative of cataract
formation
Redness, itching, edema, inflammation, ulcerations of the eyelids, eyelashes, sclerae, and
conjunctivae to determine the cause, for example,
reactions to environmental allergens, infectious
process (blepharitis, conjunctivitis, hordeolum,
entropion, ectropion, trachoma, scleritis, iritis)
Detection of conjunctival and corneal injuries by
foreign bodies and determination of ocular penetration or anterior chamber hemorrhage
Detection of deficiency in tear formation indicative of lacrimal dysfunction, causing dry eye
disease, which can lead to corneal erosions or
infections
Evaluation of the fit of contact lenses
CONTRAINDICATIONS

Pupil dilation in clients with narrow-angle glaucoma
Allergies to mydriatics if used for pupil dilation

ratus, and the forehead against the bar apparatus.
The slit lamp is placed in front of the client’s eyes in
line with the examiner’s eyes. The external structures
of the eyes are inspected with the special bright light
and microscope of the slit lamp. The light is then
directed into the client’s eyes to inspect the anterior
fluids and structures; the light is adjusted for the
shape, intensity, and depth needed to visualize these
areas. The magnification of the microscope is also
adjusted to optimize visualization of the eye structures. To obtain further diagnostic information
about the eyes, special attachments and procedures
can also be used, such as a camera to photograph
specific parts, gonioscopy to determine anterior
chamber closure, and cobalt blue filter to detect
minute corneal scratches, breaks, or abrasions with
corneal staining.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include informing
the client that some blurring of vision can occur and
can last about 2 hours if the pupils have been dilated.

NURSING CARE BEFORE THE PROCEDURE

SCHIRMER TEARING TEST

Explain to the client:
That the examination is performed by a physician
and will take about 10 minutes
That the client is requested to remain still during
the examination and to look straight ahead while
the eyes are examined with the slit-lamp instrument to view the eye structures
That eyedrops can be administered to dilate the
pupils if the examination is not performed for
routine purposes
That there is no pain associated with the examination
Prepare for the procedure:
Administer an ordered mydriatic, 1 drop of 5
percent phenylephrine, in each eye and repeat in 5
to 15 minutes to achieve pupil dilation if the exam
is not performed for routine inspection.
Remove contact lenses or glasses before the examination unless the study is being performed to
check the fit and effectiveness of the contact
lenses.
Obtain a history of external and anterior eye
structure conditions and known and suspected
eye disorders, signs and symptoms of eye abnormalities, treatment regimens, and previous eye
tests and procedures and the results.

The Schirmer tearing test is a noninvasive procedure
performed to assess tear formation by the lacrimal
glands after stimulation of tearing by the introduction of a foreign object (filter paper) into the lower
conjunctival sac of the eyes. Measurement of the
moisturized portion of the paper is then made to
determine the absence of tears, or “dry eyes.” This
condition can result in corneal keratinization and
ulceration if left undiagnosed and untreated.

THE PROCEDURE

The client is seated in a dimmed room in a chair
with the feet on the floor, the chin on the rest appa-

Reference Values
Normal amount of moisture in 5 minutes is
usually 15 mm of the strip, depending on the
client’s age. The amount of moisture can be as
low as 10 mm in 5 minutes in elderly people.
INTERFERING FACTORS

Contact of the strip with the cornea, which can
cause reflex tearing
Closing of the eyes during the test, which can
increase tearing
INDICATIONS FOR SCHIRMER TEARING TEST

Diagnosis of Sjögren’s syndrome, characterized by
dryness of the eyes
Detection of tearing deficiency associated with
systemic diseases such as rheumatic disorders or
systemic lupus erythematosus

CHAPTER 24—Studies

Dry or gritty sensation in the eyes, burning, itching, photosensitivity, redness, pain, or inability to
move eyelids to diagnose dry eye disorder, especially in elderly people
Suspected tearing abnormality of the lacrimal
apparatus to determine the cause, that is,
dacryostenosis, dacryocystitis, or foreign body
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the test is performed by the physician and
that it takes about 15 minutes
That both eyes can be anesthetized and tested at
the same time and that contact lenses are not reinserted for 2 hours after the test
That a small strip of paper is gently inserted under
the lower lids and left for 5 minutes, removed, and
measured for the amount of tearing
That corrective glasses or contact lenses are
removed before the test
That there is no pain associated with the test
Prepare for the procedure:
Obtain a history of known or suspected autoimmune systemic diseases; symptoms of eye dryness;
and previous eye tests, procedures, and results.
THE PROCEDURE

The client is placed in a sitting position. A topical
eye anesthetic, 1 drop in each eye, is administered
to prevent reflex tearing, and the client is requested
to close the lids to spread the medication over the
sclerae. The sterile test strips (35- by 5-mm strips of
filter paper) are removed from their wrappers after
bending the portions to be inserted and cutting the
ends to facilitate removal. The client is requested to
look upward; the lower lid is gently pulled downward, and the bent end of a strip is inserted into the
lower conjunctival sac of one eye, toward the nasal
side. The client is requested to remain quiet and
not to rub or squeeze the lids closed during the
time that the strip is in place. The time of insertion
is recorded and the strip is left in place for 5 minutes.
The strip is removed, and the tearing response to
the irritation of the filter paper strip or the length
of the moistened portion is measured, using a
millimeter scale. The test is repeated on the other
eye. The test results are recorded as a fraction for
each eye, with the length in millimeters as the
numerator and the time in minutes that the strip
was left in place as the denominator, that is, 10 mm/5
min.53
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include
instructing the client to avoid rubbing the eyes

of Specific Organs or Systems

613

for 30 minutes or reinserting contact lenses for
2 hours after the test, if the eyes were anesthetized.
Corneal abrasion: Note and report complaints of
scratchy sensation or any change in visual acuity.
Instruct the client to avoid touching or rubbing
the eyes or inserting contact lenses if a topical
anesthetic has been instilled, because these activities can damage the cornea.

CORNEAL STAINING TEST
Corneal staining is a noninvasive procedure
performed to assist in diagnosing corneal or
conjunctival abnormalities. The test uses a sodium
fluorescein dye to stain the surface of the eyes, which
provides a more detailed view of the anterior
portions not ordinarily seen during slit-lamp examination. It allows detection of the depth and pattern
of even very small injuries to the eye, which result in
definite staining details that can be identified with a
special attachment to the slit lamp.54
Reference Values
Normal corneal surface; no keratitis, corneal
scratches, abrasions, or ulcerations
INTERFERING FACTORS

Inability of client to cooperate during the test
INDICATIONS FOR CORNEAL STAINING

Detecting minute abnormalities of the corneal
surface made visible by a fluorescein dye and visualizing with a special attachment to the slit lamp
Diagnosing the type of corneal injuries or damage
as revealed by predetermined staining patterns or
colors
NURSING CARE BEFORE THE PROCEDURE

Client teaching and physical preparation are the
same as those described in the “Visual Acuity Tests”
section.
Obtain a history of known or suspected eye disorders or injuries; signs and symptoms of eye pain,
irritation, or changes in visual acuity; or previous
eye tests, procedures, and the results.
THE PROCEDURE

The procedure is the same as that described in the
“Slit-Lamp Biomicroscopy” section except a special
blue filter is attached to observe the fluorescence
resulting from the dye. Before the slit-lamp examination, the eye surface is stained with the fluorescein
dye by touching the tip of a sterile fluorescein strip

614

SECTION II—Diagnostic

Tests and Procedures

moistened with sterile saline to the lower conjunctival sac. The client is requested to close the eye to
spread the dye over the corneal surface. Defects are
recorded depending on the amount of dye absorbed
and the color that results, that is, green for breaks,
trauma, or chemical injury to the cornea.55
NURSING CARE AFTER THE PROCEDURE

No special aftercare or assessment activities are
required after this test.
REFERENCES
1. Berkow, R: The Merck Manual, ed 16. Merck Sharp and Dohme
Research Laboratory, Rathway, NJ, 1992, p 406.
2. Ibid, pp 396–397.
3. Porth, CM: Pathophysiology: Concepts of Altered Health States, ed
5, JB Lippincott, Philadelphia, 1998, p 312.
4. Corbett, JV: Laboratory Tests and Diagnostic Procedures with
Nursing Diagnoses, ed 3. Appleton & Lange, Norwalk, Conn, 1992,
p 642.
5. Berkow, op cit, p 396.
6. Springhouse Corporation: Nurse’s Reference Library, Diagnostics,
ed 2. Springhouse, Springhouse, PA, 1986, pp 939–940.
7. Porth, op cit, pp 462–463.
8. Nurse’s Reference Library, op cit, p 934.
9. Porth, op cit, pp 347–348.
10. Ibid, p 348.
11. Berkow, op cit, pp 607–614.
12. Porth, op cit, p 482.
13. Pagana, KD, and Pagana, TJ: Mosby’s Diagnostic and laboratory
Test Reference. Mosby–Year Book, St Louis, 1992, p 611.
14. Fischbach, FT: A Manual of Laboratory and Diagnostic Tests, ed 4.
JB Lippincott, Philadelphia, 1992, p 826.
15. Ibid, p 834.
16. Ibid, pp 837–838.

17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.

Ibid, p 838.
Pagana and Pagana, op cit, p. 537.
Ibid, p 537.
Ibid, p 693.
Porth, op cit, p 383.
Ibid, p 546.
Nurse’s Reference Library, op cit, p 762.
Ibid, p 762.
Ibid, pp 783–784.
Berkow, op cit, p 2319.
Ibid, p 1939.
Ibid, p 1942.
Ibid, p 595.
Rambo, BJ (ed): Nursing Skills for Clinical Practice, ed 3. WB
Saunders, Philadelphia, 1985, pp 21–22.
Nurse’s Reference Library, op cit, p 590.
Ibid, p 601.
Berkow, op cit, p 2321.
Ibid, p 600.
Ibid, pp 2322–2324.
Nurse’s Reference Library, op cit, p 613.
Porth, op cit, p 941.
Nurse’s Reference Library, op cit, p. 608.
Ibid, p 2323.
Ibid, pp 608–612.
Ibid, pp 602–604.
Ibid, pp 549–550.
Ibid, pp 548–549.
Berkow, op cit, p 1429.
Ibid, p 1429.
Porth, op cit, pp 1044–1045.
Nurse’s Reference Library, op cit, p 566.
Ibid, p 789.
Ibid, p 557.
Berkow, op cit, p 2363.
Ibid, p 562.
Nurse’s Reference Library, op cit, p 561.
Ibid, pp 563–564.
Ibid, p 562.
Ibid, p 562.

CHAPTER

Skin Tests
TESTS COVERED
Scratch Tests for Allergens, 616
Patch Tests for Allergens, 617
Intradermal Tests for Allergens, 617
Tests for Immune Competence, 618
Tuberculin Tests, 620

Mumps Test, 621
Histoplasmosis/Coccidioidomycosis/
Blastomycosis Skin Tests, 622
Trichinosis/Toxoplasmosis Skin Tests, 623

INTRODUCTION

Skin tests provide biologic and diagnostic information about hypersensitivity, as in the strength of body reactivity to harmful agents (allergens); about immunity, as
in the susceptibility of resistance of the body to harmful agents (infectious disease); and about
cell-mediated immune function, as in the presence or absence of a hypersensitive inflammatory
response to an antigenic agent (immune competence). The five types of skin testing are the
following: (1) scratch, (2) patch, (3) culture, (4) multipuncture, and (5) intradermal injection.
Test reliability depends on (1) a faultless injection procedure (intradermal rather than subcutaneous [SC]); (2) scratch, patch, and culture procedures; (3) correct sites and site identification
records; (4) correct dilution and measurement of the antigen; and (5) accurate reading, measurement, and recording of skin reactions.
Skin tests are generally considered microbiologic invasive procedures because a break in skin
integrity is essential to introduce the allergens, toxins, or antigens to obtain a systemic response
to the disease-producing agent. Some tests are performed routinely as screening procedures or
specifically when symptomology indicates the need. Some tests are performed primarily on
children, some on adults, and some on both. Skin tests can be performed by the physician or a
nurse in a hospital, clinic, or physician’s office.

TESTS FOR ALLERGENS
Skin tests for allergens are performed to determine
unknown and suspected hypersensitivities (allergies) to environmental substances that are inhaled
(dust, pollens, animal dander, grasses, molds), foods
that are ingested (eggs, wheat, shellfish, citrus
fruits), substances that are injected (horse serum,
insect venom), or drugs (penicillins) that cause
atopic diseases. Provocative food testing can be
performed to determine food sensitivities because
skin tests are of doubtful clinical significance. Skin

tests are performed by patch tests that confirm a
contact sensitivity and by scratch and intradermal
tests that use allergenic extracts to confirm sensitivity to various substances. An exaggerated response
to the substances (antigens) introduced by direct
skin testing is considered a positive response if a
wheal and flare reaction becomes obvious in 15 to
20 minutes.
The results of skin testing for hypersensitivities
lead to various treatment modalities. One method
is to avoid the identified allergens; if avoidance is
not possible, desensitization (immunotherapy) is
615

616

SECTION II—Diagnostic

Tests and Procedures

attempted to control or relieve the symptoms. Desensitization is accomplished by the year-round SC
injection of increased doses of the extract of the
allergen. Another treatment is to selectively eliminate specific foods from the diet until symptoms are
relieved or to start with a diet that eliminates
all potential allergens and gradually add one food
at a time until symptoms recur (provocative food
testing).1

SCRATCH TESTS FOR ALLERGENS
Scratch tests are direct skin tests to detect sensitivities to allergens. They are performed by applying a
test solution containing the antigen to shallow
scratches in the skin. This type of skin testing is safer
than injections because a smaller amount of the
antigen is introduced. Scratch tests are often
performed before intradermal injection tests for
allergens to identify materials that can cause a severe
systemic response. They are always performed
instead of intradermal tests if the client has a known
severe sensitivity to a substance. If a positive wheal
and flare (redness and swelling) response measuring
0.5 cm or more is observed, intradermal injection
tests should not be performed.
Reference Values
Negative reaction, no evidence of a wheal and
flare reaction of 0.5 cm or larger than control
test in 15 to 20 minutes after application of test
extract
INTERFERING FACTORS

Using scratches that are made too deeply, causing
bleeding to occur
Touching the skin with the dropper, causing
contamination when applying the substance
Using antigens that have expired
Using antihistamines
INDICATIONS FOR SCRATCH TESTS FOR
ALLERGENS

Determining allergic response to various antigens
before intradermal testing in clients who have a
history of severe sensitivities
Suspected allergic condition to confirm sensitivity
to an antigen
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the tests are performed by a physician or a

nurse and that they take 30 to 45 minutes to
administer, including reading of the results of the
tests
That a series of scratches are made on the lower
forearm or back and a drop of a different allergen
is introduced into each scratch
That a moderate amount of pain is experienced
when the scratches are made
Prepare for the procedure:
Request that the client remove the clothing from
the waist up if the back is to be used for testing,
and provide a gown to wear with the opening to
the back.
Obtain a history of known allergies to substances,
desensitization therapy, diseases or conditions
known to be caused by allergens, and severity of
symptoms when exposed to allergens.
Use distraction techniques in children.
THE PROCEDURE

The skin sites on the lower anterior portion of the
forearm or the scapular area of the back are cleansed
with alcohol or acetone swabs and allowed to airdry. The sterile lancet is removed from the package
and held in the dominant hand. The skin at the sites
is held taut with the nondominant hand, and
scratches are made 1 cm long and 2.5 cm apart with
the sterile lancet or needle. The scratches should be
made through the uppermost layer of the skin
(epidermis) without causing bleeding. A drop of the
concentrated (1:20) test extract is placed on each
scratch without touching the skin to avoid contamination of the substance. The tests can also be
performed by using commercially produced scarifiers and puncturing the skin through a drop of the
test extract. Control tests are performed simultaneously by intradermal injection of the diluent. The
tests are read in 15 to 20 minutes for a wheal and
flare reaction and, if a wheal is present and the diameter is more than 0.5 cm larger than the control
wheal, the test is positive for the test extracts producing it. An intradermal test using histamine (0.01
mg/mL) or morphine (0.1 mg/mL) is performed if
the wheal is smaller than 0.5 cm or if no wheal
(negative test) results. These control tests produce a
wheal that measures 1 cm or less when the scratch
tests are negative. They are performed when the
client has been taking drugs that block the effect of
histamine on blood vessels and inhibit the skin tests
(histamine, hydroxyzine) or drugs that are mast
cell degranulators (morphine, meperidine).2 A
record is made of the allergens and their sites for the
later identification of substances causing a positive
reaction.

CHAPTER 25—Skin

NURSING CARE AFTER THE PROCEDURE

Care and assessment after the tests include assessing the sites and any systemic effects of the tests.
Inform the client that any redness or edema at the
sites will disappear within 24 hours.

PATCH TESTS FOR ALLERGENS
Patch tests are direct skin tests to detect and confirm
contact sensitization to allergens. Common potentially irritating substances (allergens) are applied to
disks of filter paper, cotton squares, or gauze squares
and securely taped to the skin. Unknown and
suspected allergens can be tested when unexplained
contact dermatitis and other skin eruptions are present, although the tests do not produce a definitive
cause of the condition. A response of redness or
edema at the site of application indicates a contact
sensitivity to the substance.3
Reference Values
Negative reaction; no evidence of redness or
edema at the site after the removal of the patch
INTERFERING FACTORS

Corticosteroids (systemic or topical), which can
affect test results
Impure or insufficient concentration of the
antigen
Improper technique in applying the patch, reactions to the tape on the patch, or incorrect reading
of the results
Contamination of the patch during application
INDICATIONS FOR PATCH TESTS FOR
ALLERGENS

Determination or confirmation of contact sensitivities to substances
Unexplained skin eruptions or dermatitis conditions to determine whether allergic contact is the
cause
CONTRAINDICATIONS

Areas with skin eruptions or any kind or inflammation should not be used as test sites.
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the patches are applied by the physician or
the nurse and left in place for 48 hours, removed,
and read for reactions to the substance

Tests

617

That no pain is associated with the test
Prepare for the procedure:
Ask the client to remove clothing from the waist
up if the back is to be used, and provide a gown to
wear with the opening to the back.
Obtain a history of skin disorders, suspected or
known contact dermatitis disorders, medications
taken, or other known or suspected allergies.
THE PROCEDURE

The sites on the inner aspect of the lower forearm or
the scapular area of the back are cleansed with alcohol or acetone swabs and allowed to air-dry. Remove
the cover of each patch from the pad containing the
testing substance of common allergens, and apply
the pads to the sites by firmly pressing down on the
adhesive surrounding the pads. Patch testing can
also be performed by placing the potentially irritating substances (diluted to a 1 to 2 percent strength in
water or mineral oil) on a small circle of filter
papers, covering with plastic, and taping to the sites.
A record is made of the allergens and their sites for
later use to identify the substances that reveal a positive reaction. Patches are left in place for 48 hours, at
which time they are removed and the test sites read
immediately and in 30 minutes. Some can be evaluated again 4 days after removal of the patches for any
delayed reactions. Positive reactions can range from
a slight irritation to redness and edema to vesicle
and ulcer formation.4
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the tests include the
evaluation of the test results and the application
of an ordered topical corticosteroid to relieve
severe effects of a positive reaction.
Severe reaction: Note and report pain, irritation,
or pruritus at the sites. Remove the patch and
apply steroid ointment.

INTRADERMAL TESTS FOR ALLERGENS
Intradermal tests are direct skin tests to detect sensitization to allergens that cause clinical conditions
such as asthma, rhinitis, anaphylaxis, insect sting
reactions, and food and drug reactions manifested
by urticaria, angioedema, bronchial or gastrointestinal muscle spasms, or hypotension.5 A series of
common allergen extracts are injected intradermally
to determine reactions within a specific period. A
wheal and flare reaction of 0.5 cm or larger is
considered a positive response and usually correlates
with the presenting symptoms.

618

SECTION II—Diagnostic

Tests and Procedures

Reference Values
Negative reaction; no evidence of a wheal reaction of 0.5 cm or larger than the control wheal in
15 minutes after injection of the test extract
INTERFERING FACTORS

Improper technique in performing the intradermal injections and injecting the test extract into
subcutaneous tissue
Incorrect concentration and measurement of the
test extract
INDICATIONS FOR INTRADERMAL TESTS FOR
ALLERGENS

Determination or confirmation of allergic sensitivities to specific substances that induce exaggerated reactions in a sensitive host
Unexplained single episode or seasonal or yearround symptoms caused by inhalants, foods,
drugs, or injected substances
Determination of the need for desensitization to
the allergen
CONTRAINDICATIONS

Areas that have skin eruptions or inflammation
should not be used as test sites.

needle is inserted into the top level of the skin
with the dominant hand holding the syringe almost
level with the site. Material that is injected into
subcutaneous tissue instead of intradermal tissue
will cause invalid test results. The text extract is
injected, and, if more than one test is to be
performed, the next test extract is injected 2.5 cm
from the initial site. This process is repeated until all
test materials have been injected. Control tests of the
diluent are performed simultaneously for comparison. The sites are examined in 15 minutes for any
reactions. A wheal and flare reaction that is more
than 0.5 cm larger than the control wheal 15 minutes
after the injection is considered to be a positive
response. A record of the sites and test extracts is
made for identification of substances causing a positive reaction.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the tests include assessing the sites and any systemic effects from the test
extracts.
Inform the client that any redness or edema at the
sites should disappear within 24 to 48 hours.
Severe systemic response: Note and report urticaria, dyspnea, or hypotension. Administer ordered antihistamine or epinephrine, depending on
the severity of the reaction.

NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the physician or nurse performs the test,
which takes 15 to 30 minutes, including reading of
the results
That a series of injections are given under the skin
to introduce the test extract
That the client waits for 15 minutes after the
injections for the test to be read for responses that
indicate a sensitivity
That moderate pain and discomfort are experienced when the injections are given
Prepare for the procedure:
Obtain a history of known and suspected allergies, diseases, or conditions known to be caused
by allergens, and severity and frequency of symptoms.
THE PROCEDURE

The skin sites on the lower anterior area of the forearm are cleansed with alcohol or acetone swabs
and allowed to air-dry. The test extract, usually
0.02 mL of a 1:500 or 1:1000 concentration, is drawn
up into a tuberculin syringe with a short 26-gauge
needle attached. A different syringe is used for
each test extract. The skin is held taut with the
nondominant hand and, with the bevel up, the

TESTS FOR IMMUNE
COMPETENCE
Immune competence tests are performed to determine cell-mediated immune response by skin testing
with the intradermal injection of several commonly
encountered antigens. The reading of the test results
provides information about an intact cell-mediated
immune function by a positive, delayed hypersensitivity response at the injection site and indicates a
present or past exposure to the antigen used. A negative response indicates no exposure to the antigen or
an ineffective immune response to the antigen
(anergy). Anergy indicates an impaired immunity
and can occur in advanced stages of infectious
diseases or in chronic diseases such as lymphoma or
sarcoidosis. Tests (and their associated diseases)
related to the antigens that commonly cause an
immune response are candidin (Candida albicans),
streptokinase-streptodornase (streptococcal infections), Mantoux (purified protein derivative [PPD]
tuberculosis), trichophytin (ringworm), and others.
INTERFERING FACTORS

Improper technique in performing the intradermal injections and injecting the antigen into
subcutaneous tissue instead of intradermal tissue

CHAPTER 25—Skin

Tests

619

Reference Values
Positive response at the injection site
Candidin: 10 mm or more induration and erythema in 48–72 hr
Streptokinase-streptodornase: 10 mm or more induration in 48 hr
Mantoux: 10 mm or more induration and erythema in 24–72 hr
Trichophytin: 5 mm or more induration in 48–72 hr
Incorrect dilution or measurement of the amount
of antigen administered
Use of expired antigens, contaminated antigens,
or improperly stored antigens
Incorrect measurement and timing of the reading
of the skin responses to the antigens
Oral contraceptives, corticosteroids, and other
immunosuppressive drugs
Age of the client, because infants under 3 months
have immature immune systems and elderly
people have a decrease in sensitivity with age
INDICATIONS FOR TESTS FOR IMMUNE
COMPETENCE

Detecting impaired or intact cellular immunity by
evaluation of the immune responses to the test
antigens
Monitoring chronic diseases such as Hodgkin’s
disease, sarcoidosis, leprosy, or chronic renal failure to determine the course and prognosis of the
disease
Evaluating the effectiveness of immunotherapy
after administration of steroids and vaccines such
as bacille Calmette-Guérin6
CONTRAINDICATIONS

Sites that have dermatitis, inflammation, or
breaks in the skin should not be used for testing.
Hypersensitivity to any antigen to be used in the
tests.
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the physician or the nurse performs the
series of skin injections, which take 10 to 30
minutes to administer, depending on the number
of antigens injected, and that a reaction should
appear in 48 to 72 hours
That the client is requested to come back to have
these test reactions read in 48 or 72 hours
That moderate pain may be experienced when the
injections are performed
Prepare for the procedure:
Obtain a history of known and suspected diseases
and conditions reflected or affected by abnormalities of the immune system, hypersensitivity to the

test antigens, other allergies, and past skin tests
and responses.
THE PROCEDURE

The skin sites on the lower anterior surface of the
forearms are cleansed with alcohol or acetone swabs
and allowed to dry. Small doses of correctly diluted
antigens are prepared in tuberculin syringes with 26to 27-gauge needles attached. Each antigen is
injected intradermally, making a small bleb under
the skin (see the procedure in the “Tuberculin Tests”
section that follows), and the site is circled and
labeled. The sites are examined with good lighting
for the presence of induration and are measured in
millimeters with a metric ruler in 48 and then 72
hours. This reaction indicates a positive test result.
Absence of induration or erythema indicates a negative test result.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include evaluating for local and systemic reactions to the antigens
for 15 to 30 minutes and informing the client to
avoid any scratching of the sites or washing of the
marks.
Inform the client of the time to return for a reading and evaluation of the test sites.
Severe local response: Note and report pain,
edema, itching, or blister formation. Administer
ordered corticosteroids. Inform the client that
hyperpigmentation can result and can last for up
to 2 weeks.
Anaphylactic shock: Note and report respiratory
distress, hypotension, or tachycardia. Administer
ordered epinephrine SC. Have resuscitation
equipment and supplies on hand.

TESTS FOR INFECTIOUS
DISEASES
Skin tests for infectious diseases are performed to
determine past or present exposure to an infectious
agent (sensitivity) or susceptibility or resistance to
an infectious disease (immunity). The tests involve
the administration of the specific antigen prepared
for a specific disease by intradermal injection (most

620

SECTION II—Diagnostic

Tests and Procedures

common), multipuncture, patch, or scratch techniques. Included in this section are skin tests for
infectious microorganisms such as bacteria (tuberculosis, diphtheria, scarlet fever), viruses (mumps),
fungi (histoplasmosis, coccidioidomycosis, blastomycosis), and parasites (trichinosis, toxoplasmosis).

TUBERCULIN TESTS
Tuberculin tests are skin tests that use a PPD or
old tuberculin (OT) of the tubercle bacillus administered by intradermal injection (Mantoux) or
multipuncture technique (Tine) to determine sensitization to the tuberculosis bacillus from a previous
exposure, not the actual presence of the disease.
Tuberculosis is an infectious disease caused by
Mycobacterium tuberculosis and is transmitted by
droplet nuclei particles harbored in the respiratory
tract and in the secretions of those with the active
disease. A positive response of induration and
erythema that appears at the site in 48 to 72 hours
reveals the development of a cell-mediated immunity to the organisms or a delayed hypersensitivity
caused by interaction of the sensitized T lymphocytes with the tuberculin antigen. The tests are used
on children and adults to screen for or to diagnose
active or dormant tuberculosis.
Primary (initial infection) tuberculosis is always
asymptomatic, and secondary (subsequent infection) tuberculosis is usually asymptomatic, with the
main diagnostic evidence of the disease obtained by
a positive skin test and the presence of lesions on the
chest x-ray. In the multipuncture technique, PPD
(Aplitest, Sclavo Test) or OT (Tine, Mono-Vacc) is
used; this test is usually performed to screen for
the disease in asymptomatic clients. Verification
of a positive response of a multipuncture test is
performed with the more definitive Mantoux test
(Aplisol, Tubersol), which allows more precise measurement of the antigen. A positive response of the
Mantoux is followed by chest radiography and
bacteriologic laboratory tests to confirm a diagnosis
of tuberculosis.7
Reference Values
Negative response or minimal response, with no
exposure to tuberculosis
Tine test: Less than 2 mm or absence of induration around one or more of the punctures in
48–72 hr
Mantoux test: Less than 5 mm or absence of
induration and erythema in 24–72 hr

INTERFERING FACTORS

Improper technique in performing the intradermal injection and injecting the PPD or OT into
subcutaneous tissue
Incorrect reading (measurement of the response)
or timing of the reading
Incorrect amount or dilution of antigen injected
or delay in the injection after drawing the antigen
up into the syringe
Improper storage or contamination of the antigen
Recent or present bacterial, viral, or fungal infections
Diseases such as hematologic malignancies or
sarcoidosis
Immunosuppressive drugs or steroids, which can
alter results
INDICATIONS FOR TUBERCULIN TESTS

Screening of asymptomatic clients for tuberculosis exposure or infection
Routine screening of infants with the Tine test at
the time of first immunizations to determine
tuberculosis exposure
Recent known or suspected exposure to tuberculosis with or without symptoms to determine
whether tuberculosis infection is present
Cough, weight loss, fatigue, hemoptysis, and
abnormal x-rays to determine whether the cause
is tuberculosis
Medical conditions that place the client at risk for
tuberculosis, such as acquired immunodeficiency
syndrome, lymphoma, or diabetes
Populations at risk for developing tuberculosis,
such as nursing home residents, prison inmates,
and residents of the inner city living in poor
hygienic conditions
Mantoux test to confirm findings of a positive
Tine test
CONTRAINDICATIONS

History of tuberculosis or previous positive skin
test
Rash or other eruptions at the injection site
Hypersensitivity to other skin tests or vaccinations
NURSING CARE BEFORE THE PROCEDURE

Explain to the client:
That the nurse performs the test by injecting a
small amount of medicine under the skin of the
forearm and that the test takes about 5 to 10
minutes
That the nurse will inform the client of the time to

CHAPTER 25—Skin

return to have the skin test read and will provide
instructions after the reading
That the area should not be scratched or
disturbed from the time of the injection until it is
read
That a moderate amount of pain can be experienced when the injection is given
Prepare for the procedure:
Obtain a history of tuberculosis or tuberculosis
exposure, signs and symptoms indicating possible
tuberculosis, other diagnostic procedures and
results, and other skin tests or vaccinations and
sensitivities.
THE PROCEDURE

The skin site on the lower anterior portion of the
forearm is cleansed with alcohol or acetone swabs
and allowed to air-dry.
Multipuncture Test. The cap covering the tines is
removed, and the skin of the forearm is stretched
taut. The device is firmly pressed onto the prepared
site and held in place for a second and removed. The
four punctures should be visible. The site is
recorded, and the client is reminded to return in 48
to 72 hours to have the results read. The diameter of
the largest indurated area is measured in a good light
with a plastic ruler. A palpable induration of 2 mm
or more at one or more of the punctures indicates a
positive test result. A Mantoux test is then
performed to confirm the positive results unless
vesicles appear at the site.
Intradermal Test. The PPD or OT is prepared in a
tuberculin syringe with a short 26-gauge needle
attached. The appropriate dilution and amount are
prepared for the most commonly used intermediate
strength (5 tuberculin units in 0.1 mL) or for a first
strength, which is usually used for children (1 tuberculin unit in 0.1 mL). The preparation is injected at
the prepared site intradermally, that is, within the
layers of the skin, as soon as it is drawn up into the
syringe, causing a bleb or wheal to form. The site is
recorded and the client is reminded to return in 48
to 72 hours to have the test read. The arm is
inspected in good light, and the diameter of any
induration is measured with a plastic ruler and
palpated for thickening of the tissue. A positive
result is indicated by a 10-mm or more reaction with
erythema and edema. A positive test result is not a
definite diagnosis of tuberculosis; however, it does
mean that there is a great chance that the disease is
present if the client presents symptoms. A positive
test result in a well person indicates that the client

Tests

621

has had tuberculosis in the past or is infected with a
different bacteria.
An induration of 5 to 9 mm is considered doubtful and possibly caused by another infection. This
response warrants a repeat test. A higher concentration of the antigen can be administered to those who
do not have a reaction from the intermediate dose.
Subsequent chest x-rays and culture of the sputum
for microorganism identification are performed to
confirm a diagnosis of tuberculosis.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test include observation of the site and a reminder to the client not
to scratch or rub it after the injection.
Remind the client to return for the reading and
explain that the effects from a positive response at
the site can remain for up to a week.
Severe positive reaction: Note and report ulceration or necrosis developing at the site. Apply cool,
wet compresses and topical corticosteroids to the
injection site.

MUMPS TEST
The mumps test is a skin test performed to determine the previous exposure to or the active presence
of the disease. Mumps, or parotitis, is an infectious
disease of the parotid glands caused by a myxovirus
and transmitted by direct contact with an infected
person or the droplets spread from the saliva of an
infected person. The mumps test involves intradermal injections of an antigen from infected animals
and of a material made from noninfected animals to
serve as a control. The measurement of the response
is made in 48 hours, with a positive response of
erythema with or without induration indicating
varying degrees of protection from or resistance to
the mumps virus and a negative response with no
reaction indicating susceptibility to the mumps
virus. The test is also used as part of the series to
determine immune competence.8
Reference Values
Negative response or no reaction at the test site
or minimal response of erythema measuring
less than 10 mm indicates susceptibility to
mumps with routine use of mumps vaccine
since 1997.
INTERFERING FACTORS

Improper technique in performing the skin test or

622

SECTION II—Diagnostic

Tests and Procedures

inaccurate time or measurement in reading the
reaction
INDICATIONS FOR THE MUMPS TEST

Detecting impaired or intact cellular immunity
when used with other test antigens to test
immune responses
Determining resistance to or protection against
the mumps virus by a positive reaction or susceptibility to mumps by a negative reaction
Evaluating mumps-like diseases and differentiating between them and actual mumps
NURSING CARE BEFORE THE PROCEDURE

Teaching and physical preparation are the same as
for any diagnostic skin test (see section under “Tests
for Immune Competence”).
The history should include prior exposure to the
disease and past immunizations.
THE PROCEDURE

The skin sites on both lower anterior portions of the
forearms are cleansed with alcohol or acetone swabs
and allowed to air-dry. The inactivated vaccine
prepared from infected animals and the vaccine
prepared from noninfected animals are drawn up
into tuberculin syringes with 26-gauge needles
attached. Both are injected intradermally, and the
site is recorded. The client is reminded to return in
48 hours to have the test read. A positive result
consists of erythema with or without induration at
least 10 mm in diameter, indicating some protection
against mumps. A positive reaction at the onset of a
mumps-like disease can rule out mumps as the
cause. A delayed positive reaction that occurs several
days after the test can indicate the presence of
mumps and no previous exposure. The lack of
erythema indicates a negative result and lack of
resistance to the disease.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test are the same as for
any diagnostic skin test (see section under “Tests for
Immune Competence”).

HISTOPLASMOSIS/
COCCIDIOIDOMYCOSIS/
BLASTOMYCOSIS SKIN TESTS
Histoplasmosis, coccidioidomycosis, and blastomycosis skin tests are performed to determine exposure
to these fungal infections affecting the pulmonary
system. Diagnosis of these fungal diseases is made by
visualization and identification of the organisms

and by measurement of antibodies produced in
response to a specific infection.
Histoplasmosis is caused by the fungus
Histoplasma capsulatum and is transmitted by
inhalation of spores in the dust that are released
when soil contaminated with bird excreta is
disturbed. The manifestations of histoplasmosis are
similar to those of tuberculosis. It can be a mild, selflimiting respiratory infection or a chronic disorder
that can lead to the progressive destruction of lung
tissue. The skin test involves the intradermal injection of an antigen, histoplasmin, prepared from
killed fungi obtained by culture. The skin test is read
in 48 to 72 hours for a positive response of induration and erythema at the site; response can remain
positive after the initial infection has occurred, indicating a past or present origin of the disease. Other
tests that provide diagnostic information are the
complement fixation and the immunodiffusion
tests, which test and measure antibodies produced
by exposure. Both tests can become positive after
symptoms appear. Cultures of specimens of sputum,
urine, oral lesions, or lymph nodes are also obtained
to confirm the presence of the disease by visualization and identification of the specific organism.
Coccidioidomycosis is caused by the fungus
Coccidioides immitis and is transmitted by inhalation
of the spores found in the dust from disturbed soil
containing the organisms. It occurs as a self-limiting
infection manifested as an upper respiratory infection or pneumonia or as a chronic, progressive
disseminated disease involving the lungs and spreading to the bones, joints, skin, liver, and brain. The
skin test involves the intradermal injection of an
antigen, coccidioidin or spherulin, prepared from a
culture filtrate of the organism causing the disease.
The test is read in 24 to 72 hours, and a positive
response is revealed by induration and erythema. A
skin reaction appears 10 to 21 days after the infection has occurred and remains positive throughout a
lifetime, even though the organisms and disease
have been eliminated. Other tests that provide diagnostic information are the complement fixation and
tube-precipitin tests as well as the culture of sputum,
pleural fluid, pus, skin lesions, and gastric washings
to visualize and identify the spherules.
Blastomycosis is caused by the fungus Blastomyces
dermatitidis and is characterized by an acute infection manifested by lesions of the lungs and skin. The
infection can be self-limiting or can progress to
involve bone, prostate gland, testes, and oral mucosa.
The skin test involves the intradermal injection of an
antigen, blastomycin, and it is commonly performed
in conjunction with the skin tests for histoplasmosis

CHAPTER 25—Skin

Tests

623

Reference Values
Histoplasmosis: Negative response of no reaction at the test site or minimal erythema
measuring less than 5 mm with an absence of induration, indicating absence of
infection
Coccidioidomycosis: Negative response of no reaction at the test site or minimal
induration and erythema of less than 5 mm, indicating absence of infection
Blastomycosis: Negative response of no reaction at the test site or minimal erythema
measuring less than 5 mm with an absence of induration, indicating absence of
infection
and coccidioidomycosis. The test is read in 48 hours,
and a positive response reveals induration and
erythema at the site, indicating a past or present
infection. Because the test lacks specificity, it is
thought to be of little value in diagnosing the
disease. A culture of sputum, pus, or exudate and
preparation by the proper fixation and staining to
visualize the budding yeasts are done to provide a
more definitive diagnosis of the disease.9
INTERFERING FACTORS

Improper technique in performing the skin tests,
inaccurate recording of sites or time, or inaccurate
measurement in reading the reaction
INDICATIONS FOR HISTOPLASMOSIS/
COCCIDIOIDOMYCOSIS/
BLASTOMYCOSIS SKIN TESTS

Diagnosing past or present acute or chronic infection by a specific fungal microorganism as
evidenced by a positive skin test in histoplasmosis
and blastomycosis
Evaluating improvement in a diagnosed blastomycosis infection
Diagnosing an active coccidioidomycosis infection in the presence of symptoms as evidenced by
a positive skin test
NURSING CARE BEFORE THE PROCEDURE

Teaching and physical preparation are the same as
for any diagnostic skin test (see section under “Tests
for Immune Competence”). A history should
include exposure to any fungal infective agents or
residence in an endemic area.
THE PROCEDURE

The skin sites on the lower anterior portion of the
forearm are cleansed with alcohol or acetone swabs
and allowed to air-dry. Three tuberculin syringes
with 26-gauge needles attached are prepared with
the antigens histoplasmin, coccidioidin, and blastomycin. Each antigen is injected intradermally, and

the sites are labeled and noted for each. The client is
reminded to return for the test to be read, 24 to 72
hours for histoplasmosis, 24 to 72 hours for coccidioidomycosis, and 48 hours for blastomycosis. All
three tests are usually performed and read at the
same time. A positive result for histoplasmosis
reveals a measured area of erythema and induration
of 5 mm or more, and a negative reaction is an
absence of induration and erythema of less than 5
mm. A positive result for coccidioidomycosis reveals
a measured induration of 5 mm or more and a negative reaction of less than 5 mm. A positive result for
blastomycosis reveals a measured area of erythema
and induration of 5 mm or more. A doubtful result
is revealed by erythema alone or induration of less
than 5 mm, and a negative reaction is an absence of
induration and erythema of less than 5 mm. A positive test of any of the fungal infections indicates past
or present infection.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test are the same as for
any diagnostic skin test (see section under “Tests for
Immune Competence”).

TRICHINOSIS/TOXOPLASMOSIS SKIN
TESTS
Trichinosis and toxoplasmosis skin tests are
performed to determine exposure to those parasitic
diseases. Although the skin tests are discouraged and
are considered unreliable, commercially available
antigens are available and can be used in conjunction with serologic tests to detect antibodies after the
onset of the disease.
Trichinosis is caused by the parasite Trichinella
spiralis and is transmitted by the ingestion of raw or
partially raw pork containing the larvae. The larvae
invade the stomach and duodenum and penetrate
the duodenal and jejunal mucosa. The disease is
manifested by gastrointestinal symptoms followed
by edema of the eyelids and eye pain, muscle pain,

624

SECTION II—Diagnostic

Tests and Procedures

fever, and chills, among other systemic symptoms.
The skin test involves the intradermal injection of an
antigen, T. spiralis, prepared from the killed larvae. It
is read 15 minutes after injection, with a positive
response consisting of a wheal and erythema at the
site. Other tests performed to obtain diagnostic
information include the complement fixation, indirect fluorescent antibody, precipitin, and flocculation tests. Biopsy of muscle tissue later in the
infection can reveal the larvae or myositis, indicating
the presence of the disease.
Toxoplasmosis is caused by the protozoan parasite
Toxoplasma gondii and is transmitted transplacentally by the mother’s ingestion of raw or partially raw
meat containing the cysts or by exposure to the cysts
in cat feces. It can also be acquired and can occur as
a mild infection, as a disseminated infection in those
who are immunodeficient, or as a chronic infection.
The skin test involves the intradermal injection of an
antigen, toxoplasmin, which is read in 24 to 48
hours, with a positive result producing erythema at
the site. The most definitive diagnostic information
is obtained by performing tests for IgM antibodies
initially and, later in the disease, for IgG antibodies,
detected by the indirect fluorescent antibody procedure, complement fixation, and indirect hemagglutination.10
Reference Values
Negative response or no reaction at the test sites,
indicating absence of a specific infection

INTERFERING FACTORS

Improper technique in performing the skin test or
inaccurate time or measurement in reading the
reaction
Commercially available antigens for the trichinosis test, which are considered unreliable for
diagnostic purposes
INDICATIONS FOR TRICHINOSIS/TOXOPLASMOSIS
SKIN TESTS

Diagnostic adjunct for trichinosis in conjunction
with serology and muscle biopsy

Diagnostic adjunct for toxoplasmosis in conjunction with serology
NURSING CARE BEFORE THE PROCEDURE

Teaching and physical preparation are the same as
for any diagnostic skin test (see section under “Tests
for Immune Competence”).
A history should include dietary inclusion of
uncooked meats and possible exposure to infected
cats, and the results of serologic tests performed
to identify the microorganisms causing the
diseases.
THE PROCEDURE

The skin site on the lower anterior portion of the
forearm is cleansed with alcohol or acetone swabs
and allowed to air dry. T. spiralis antigen or toxoplasmin is prepared in a syringe with a 26-gauge
needle attached and injected intradermally for the
test to be performed, trichinosis or toxoplasmosis,
respectively. The test for trichinosis is read in 15 to
20 minutes. The client is reminded to return in 24 to
48 hours to have the test read for toxoplasmosis. A
positive result for trichinosis reveals a wheal with
surrounding erythema; it is considered a questionable positive result if the reaction occurs after 24
hours. A positive result for toxoplasmosis reveals a
measured erythema of more than 10 mm.
NURSING CARE AFTER THE PROCEDURE

Care and assessment after the test are the same as
for any diagnostic skin test (see section under “Tests
for Immune Competence”).
REFERENCES
1. Berkow, R: The Merck Manual, ed 16. Merck Research Laboratory,
Rahway, NJ, 1992, pp 320–321.
2. Ibid, p 320.
3. Springhouse Corporation: Nurse’s Reference Library: Diagnostics,
ed 2. Springhouse, Springhouse, Pa, 1986, p 1042.
4. Ibid, p 1043.
5. Berkow, op cit, p 320.
6. Ibid, p 1040.
7. Ibid, p 134.
8. Fischbach, FT: A Manual of Laboratory Diagnostic Tests, ed 4. JB
Lippincott, Philadelphia, 1992, pp 452–453.
9. Berkow, op cit, p 165.
10. Ibid, p 235.

APPENDIX

Obtaining Various Types
of Blood Specimens
Most hematology tests, as well as numerous
other laboratory tests, require venous blood.
Microsamples of capillary blood may be obtained
from the fingertips or earlobes of older children and
adults and from the heels of infants and neonates.
Capillary punctures can also be used instead of
venipunctures if the client has poor veins, very small
veins, or a limited number of usable veins and if the
client is extremely apprehensive about having a
venipuncture. When the amount of blood needed is
greater than 1.5 mL, however, a venipuncture must
be performed.
Blood samples can also be obtained from vascular
access devices such as heparin locks, triple-lumen
subclavian catheters, and right atrial catheters. In
the sick or high-risk neonate monitored in a neonatal intensive care unit, blood samples can be
obtained from an indwelling catheter positioned
and secured in an umbilical vein and connected
to a heparin lock system to prevent clotting in
the needle. Such procedures avoid the necessity of
repeated skin punctures and must be performed
with strict aseptic technique to avoid contamination
of the indwelling device or catheter and to prevent
possible septicemia. Special techniques are performed when obtaining samples from indwelling
devices or catheters to avoid altered results
from drugs and intravascular infusions and, in
the neonate, to avoid excessive blood loss resulting
from the need for numerous laboratory blood
analyses.
Recent advances allow fetal blood samples to be
obtained to assess fetal health. The samples are
obtained by the physician, when special circumstances warrant it, by percutaneous umbilical cord
blood sampling (PUBS), in which blood is aspirated

from a 20- or 22-gauge spinal needle inserted into
the umbilical vessel under the guidance of ultrasonography. Fetal hematologic and metabolic status,
genetic disorder identification, and perinatal infection evaluation are the most common tests
performed through PUBS.
Tests requiring arterial blood are arterial blood
gas analyses and are obtained from the radial or
the brachial artery or from arterial lines. The
background information and clinical applications
data for arterial blood collection are found in
Chapter 5.
Nursing Alert

According to the guidelines from the Centers
for Disease Control and Prevention, gloves
should be worn when obtaining and handling
blood samples.

CLIENT PREPARATION
Client preparation is essentially the same for all sites
and for all studies.

Client Teaching
Explain to the client:
The purpose of the test
The procedure, including the site from which the
blood sample is likely to be obtained
That momentary discomfort may be experienced
when the skin is pierced
That food, fluids, and drugs are to be withheld
before to the test
625

626

APPENDIX I

For children, a doll may be used as the “patient”
for demonstration purposes. A laboratory technician’s equipment basket may hold the child’s attention during the actual procedure. For all clients,
encourage questions and verbalization of concerns
about the procedure, and provide a calm, reassuring
environment and manner.

Physical Preparation
For capillary punctures, the skin is assessed for
lesions, edema, and temperature, because the
site selected should be warm and free of lesions
or edema; application of warm compresses for
3 minutes will dilate capillaries if the skin feels
cool or looks pale or cyanotic.
For venipunctures, the condition of the veins
should be noted, and the use of tortuous, sclerotic
veins or those in which phlebitis has previously
occurred should be avoided, as should the use of
an extremity with an intravenous (IV) site or
heparin lock. If the extremity must be used,
obtain the sample from a site distal to the IV or
heparin lock. (Extremities with functioning
hemodialysis access sites should not be used, nor
should the arm on the affected side after mastectomy.)
The skin is prepared by cleansing with an antiseptic such as povidone-iodine (Betadine) or 70
percent alcohol and is allowed to air-dry or is
dried with sterile gauze. (Drying prevents dilution
of the sample with antiseptic.) For the immunosuppressed patient, povidone-iodine should be
used, followed by a 70 percent alcohol pad taped
over the site for 10 minutes—the site should be
allowed to air-dry or be dried with sterile gauze
before the venipuncture.
For blood withdrawal from a device or catheter,
assess for patency, damage, and type of catheter
to determine the need for clot removal,
heparinization, or irrigation. If a heparin lock
device is in place or attached to an indwelling
catheter in the umbilical vein, prepare heparin
in saline solution in a syringe with a needle
attached. If a right atrial catheter is in place,
prepare heparin in saline solution in a syringe
with a needle attached or prepare 30 mL saline in
a syringe to flush the catheter if blood is to be
withdrawn from a Groshong catheter. The injection site is prepared by cleansing the cathetercap junction or hub with povidone-iodine,
followed by swabbing with 70 percent alcohol for
2 minutes, and then allowing it to air-dry before
the blood withdrawal.

THE PROCEDURE
Capillary Punctures (Fingertip,
Earlobe, Heel)
The equipment needed is assembled: sterile lancet,
skin disinfectant, gauze pads or cotton balls, collection device, bandage, and materials to label the
sample. The client is placed in a position of comfort
and safety, either sitting or lying down. If an extremity is to be used, it is supported on the bed or on a
table. A small pillow or rolled towel or blanket can
be used to improve positioning of the extremity or
to promote comfort.
The site is selected and the skin prepared as
described previously. The area to be used is grasped
firmly. The skin is punctured with the sterile lancet
using a quick, firm motion to a depth of approximately 2 mm. With one wipe, the first drip of blood
is removed. If flow is poor, the site should not be
squeezed, because squeezing may produce more
tissue fluid than blood. A hand or foot may be held
in the dependent position to improve blood flow.
The sample is collected in microhematocrit tubes
or pipettes and evacuated into a container holding
the proper reagent. For smears, a drop of blood is
placed on a clean microscope slide and spread gently
with the edge of another slide. Slight pressure is
applied to the puncture site with a small, sterile
gauze square until bleeding stops.
The sample is labeled with the patient’s name and
other required identifying information and is sent
promptly to the laboratory.

Venipunctures
The equipment needed is assembled: tourniquet;
skin disinfectant; gauze pads or cotton balls; syringe
and needle or vacuumized tube, holder, and needle;
bandage; and materials to label the specimen. A 20gauge needle is usually used to prevent damage to
blood cells. Needles with smaller lumens, such as 21to 23-gauge, may be used, depending on the age of
the client, the size of the vein, and the size of the
vacuumized tube. Soft rubber tubing, approximately
1 inch wide, may be used for the tourniquet;
however, a rubber tourniquet of the same width with
a Velcro closure is preferable.
The vacuumized tubes used in collecting samples
of venous blood come in various sizes appropriate to
the age of the client or to the type of laboratory
analysis equipment and may or may not contain an
anticoagulant. The color of the rubber stopper used
to seal the tube indicates the presence and type of
anticoagulant (Table A–1). Care must be taken to

OBTAINING VARIOUS TYPES OF BLOOD SPECIMENS

ensure that the correct tube is used for the test to be
performed.
A syringe and needle may be used to obtain a
venous blood sample if it is felt that the vacuumized
tube system will collapse the vein before the volume
of needed blood is obtained. In such instances,
the sample must be transferred promptly to the
appropriate blood tube. To accomplish this transfer,
the needle is removed from the syringe and the
rubber stopper from the tube, and blood is
allowed to flow gently down the inside of the
tube. Another approach is to insert the needle
into the rubber stopper of the vacuumized tube,
allowing the vacuum to draw the blood into the
tube. This procedure can be done safely, without
hemolysis of blood cells, if the needle is 21-gauge or
larger. Most authorities recommend changing the
needle before injecting the rubber stopper. If the
sample is for a blood culture, the rubber stopper is
cleansed with povidone-iodine before the needle is
inserted.
The client is placed in a position of comfort and
safety, either sitting or lying down. The extremity to
be used is supported on the bed or on a table. A
small pillow or rolled towel or blanket can be used to
improve positioning of the extremity or to promote
comfort.
The tourniquet is applied 1 to 1.5 inches above
the site to be used, usually the antecubital area,
but the dorsum of a hand or foot can be considered.
Tourniquets should be applied tightly enough to
cause the veins to enlarge but should never occlude
arterial circulation. They should not be kept in
place for more than 1 minute before the venipuncture or for more than 2 to 3 minutes for the
entire procedure. If a vein in the arm is to be
used, the client is asked to open and close the
hand a few times and then to clench the fist. If the
puncture cannot be made within 1 minute, the
tourniquet is removed and then reapplied when the
puncture site is definitely located. This practice
prevents hemoconcentration, which may alter test
results.
The skin is cleansed as described previously (see
under “Physical Preparation”). If the vein is palpated
after the skin is prepared, the site is recleansed.
The needle cover is removed and the needle
inserted into the vein approximately one-half inch
below the point at which the needle is expected to
enter the vein itself. When the needle is smaller than
the vein, it is inserted bevel up at a 15- to 45-degree
angle through the skin. When the needle is larger
than the vein, it is inserted bevel down and almost
parallel to the skin. This technique allows the skin to

627

be punctured first and then the vein; it is a useful
approach for entering difficult veins.
If the vacuumized tube system is used, the tube is
pushed into the holder until the rubber stopper is
punctured and blood flows into the tube. If more
than one tube of blood is required, the filled tube is
removed from the holder and another inserted until
the desired number of samples is obtained. The
sequence for obtaining multiple samples using
different types of tubes is as follows: (1) blood
culture tubes (the rubber stopper must be cleansed
before insertion into the holder to prevent contamination of the sample), (2) tubes with no additives,
(3) tubes for coagulation studies, and (4) tubes with
additives (see Table A–1).
If a syringe is used, pull back on the plunger until
the desired amount of blood is obtained. The sample
is then transferred into the desired blood tubes as
described previously.
The tourniquet is released and the client is
instructed to unclench the fist. It should be released
within 1 minute after the start of blood withdrawal
if multiple samples are needed. The needle is
removed and pressure is immediately applied to the
puncture site with a gauze pad or cotton ball.
Pressure should be maintained for 3 minutes to
prevent hematoma formation. If the puncture site is
on the dorsum of the hand, the hand is elevated
while pressure is applied. Pressure is maintained
until bleeding has stopped.
The sample is labeled with the client’s name and
other required identifying information and sent
promptly to the laboratory.
Pediatric venous blood sample collections are
considered and performed only when a capillary
puncture cannot provide the amount of blood
needed or when a test is needed that can be performed only on whole blood, blood serum, or
plasma. Modifications such as needle lumen,
mentioned previously, are made according to the
child’s age. The site for older children is the same as
for adults. The site for infants can be a scalp vein or
a superficial vein of the wrist, hand, foot, or arm.
Infants and very young children require some
restraint, which can be provided by the caregiver or
nurse. Venous samples can also be obtained by aspiration from an IV infusion site, depending on the
type or components of the fluid being infused.
Children have a particular need for reassurance that
the blood loss is not a threat to their life and that the
body produces blood that replaces the blood withdrawn. Also, a Band-Aid can provide assurance that
more blood will not leak out of the body through the
puncture site.

628

APPENDIX I

Table A–1 Types of Vacuumized Tubes for Blood Tests
Color of Stopper
Red, pink

Substance in Tube
None

Action of Substance
None

Tests Used/Not Used for
Used for tests in which serum
is required (e.g., many
chemistry and serology
tests); serum is plasma that
has been withdrawn from
the body and in which the
fibrinogen has been used
during normal coagulation
of the sample
Not used for test requiring
whole, uncoagulated blood

Lavender,
purple

Ethylenediaminetetraacetic acid (EDTA)

Blocks coagulation by
binding calcium

Used mainly for hematology
tests

Causes minimal distortion
of the size and shape of
blood cells
Prevents platelet
aggregation
Light blue

Green (navy
blue, tan)

Sodium citrate

Sodium heparin

Blocks coagulation by
binding calcium

Most frequently used in
coagulation studies

May result in dilution of the
specimen due to volume
needed to anticoagulate
the sample

Not used for cell counts or
chemistry studies

Prevents coagulation by
blocking the action of
thrombin

Used for red blood cell
osmotic fragility studies

Does not alter blood cell
size

Gray

Sodium fluoride and
potassium oxalate

May cause a bluish
background when blood
smears are stained

Not used for coagulation
studies

Blocks coagulation by
binding calcium

Used primarily for blood
glucose and alcohol testing

Blocks action of enzymes in
red blood cells, which
break down glucose and
alcohol

Not used for blood glucose
tests if the laboratory uses
an enzyme testing
procedure for determining
blood glucose levels

May also inactivate cardiac
and liver enzymes
Black

Sodium oxalate

Blocks coagulation by
binding calcium
May distort blood cells
May result in dilution of
the specimen due to the
volume needed to
anticoagulate the sample

Yellow

Sodium polyanethol
sulfonate (SPS)

May also be used for selected
chemistry and toxicology
studies

Blocks coagulation
Inactivates white blood cells
and antibiotics

Not used for studies of cardiac
and liver enzymes
Used for coagulation studies
Not used for blood smears,
cell counts, or chemistry
tests

Used primarily for blood
cultures (blood sample must
be added to blood culture
bottle containing additional
SPS within 1 hour of
obtaining sample)

OBTAINING VARIOUS TYPES OF BLOOD SPECIMENS

Indwelling Devices and Atrial
Venous Catheters
Assemble all necessary equipment: disinfectant
swabs (povidone-iodine and alcohol), sterile gauze
pads, sterile injection cap, 10-mL syringe, blood
collection tubes, vial of heparin with syringe and
needle or Tubex unit dose of heparin, normal saline
in a 50-mL syringe, sterile gloves, and materials to
label the specimen.
The client is placed in a position of comfort and
safety, usually semi-Fowler’s, for blood withdrawal
from a right atrial catheter, with the cap or hub
exposed at the site of insertion, that is, right upper
chest or neck. A sitting or lying position with the
extremity supported on a small pillow or towel can
be used for blood withdrawal from a heparin lock. If
the client is a neonate, the heparin lock system is
positioned next to the neonate, taped in place, and
connected to tubing that leads to an indwelling
catheter placed in an umbilical vein. It is important
to note that frequent removal of blood from the
neonate for laboratory testing can deplete blood
volume and is the most common indication for
transfusion therapy. The development of microtechnology and electronic devices that facilitate in vivo
testing and monitoring allows continuous laboratory evaluation with a minimum of blood sampling.
All of the procedures for blood withdrawal from a
device or catheter are performed using strict sterile
technique. The heparin is prepared in a syringe or
the unit dose heparin is placed in a Tubex and the
medication allowed to warm to room temperature
for better tolerance as it enters the blood flow. The
heparin prevents obstruction of the needle or tubing
by clotting the blood. Dosage varies for the sick
neonate with an umbilical catheter in place. If a
Groshong right atrial catheter is in place, irrigation
takes place instead of heparinization. For this type of
catheter, a syringe is prepared with 30 mL of sterile
normal saline to flush the catheter. This irrigation is
performed before blood withdrawal and after total
parenteral nutrition. A syringe prepared with 20 mL
of sterile normal saline is used after blood withdrawal.
The labeled blood tubes are placed in an upright
position in a small glass. The catheter-cap junction
or hub is cleansed with a povidone-iodine swab and
a 70 percent alcohol swab for 2 minutes. Sterile
gloves are donned, the cap is removed, and a 10-mL
syringe is attached to the connector. Blood in the
catheter can cause inaccurate test results, so 6 mL of
blood is withdrawn with the syringe and the catheter
is then clamped. Clamping is not necessary if a
Groshong catheter is in place because it has a special
valve that eliminates the need for clamping. This

629

blood is discarded with the syringe. Another 10-mL
syringe is attached, and the needed amount of blood
is withdrawn, using only a moderate amount of
suction. The appropriate amount of blood is placed
in the tubes (usually 7 to 10 mL in each tube), and
blood withdrawal is continued until the tubes are
filled. Color-coded stoppers are applied to the tubes
as they are filled, and specimens that require the
blood to be mixed with substances in the tube are
gently rotated.
At the conclusion of the blood withdrawal,
heparinization of the device or catheter or flushing
of the Groshong catheter with saline is performed.
Heparinization is performed by inserting the needle
into the cap or hub and slowly injecting the prepared
syringe of medication into the device or catheter.
The catheter is then clamped 2 inches from the cap
or hub as the last of the medication is injected. The
needle is removed from the cap or hub, and the
catheter is unclamped. A new sterile injection cap or
hub is attached if the old cap is discarded. To irrigate
the Groshong, a solution of 20 to 30 mL of sterile
normal saline is gently injected through the injection cap with moderate force. The needle is then
removed, but some positive pressure is maintained
on the plunger of the syringe during withdrawal to
prevent the solution from backing up into the
syringe.
The client is left in a comfortable position after
the procedures, and the labeled specimens are
promptly sent to the laboratory.

NURSING CARE AFTER
THE PROCEDURE
After bleeding has stopped, apply an adhesive
bandage.
Application of an adhesive bandage on the finger
of a child under 6 years of age is not recommended because the child may swallow the bandage and choke on it.
Apply a new dressing to the catheter site using a
sterile 2- 2-inch gauze pad. Coil the catheter on
the dressing with the cap or hub directed upward,
cover with a transparent dressing, and tape in
place.
Rebandage and tape a heparin lock device if
necessary.

NURSING OBSERVATIONS AND
PROBLEM-SOLVING ACTIVITIES
BEFORE THE TEST

Assess the client’s understanding of the explanations provided.

630

APPENDIX I

Assess the client’s degree of anxiety about the
procedure.
Assess the infant’s or child’s need for restraint and
reassurance.
Ensure that food, fluid, and medication restrictions have been followed.
Fill out the requisition accurately and include all
information that is requested on the form.
DURING THE TEST

Note the client’s response to the procedure and
provide support if needed.
Obtain the blood sample using proper technique
and standard precaution procedures.
Avoid possible invalid testing caused by prolonged use of a tourniquet; excessive suction on
the syringe; vigorous shaking of the specimen in a
tube or expulsion from the syringe into a tube;
moisture in the syringe or tube; leakage of air into
the syringe or tube; contamination of the site,
equipment, or blood.
Provide support to the client if the puncture is not
successful and another must be performed to
obtain the blood sample.
Select appropriate evacuated tubes or syringe,
needle, and laboratory tubes, depending on tests
to be performed.
Note obstruction of vascular access device or
catheter caused by blood clotting, and notify the
physician.

AFTER THE TEST

Apply the necessary pressure to the puncture site
until the bleeding stops. If oozing continues,
elevate the extremity and apply a pressure type of
dressing.
Remain with the client until the bleeding has
completely stopped.
If the client is experiencing excessive and lingering
pain or syncope, allow the client to lie down and
rest.
Assess for extreme anxiety and signs of possible
shock state such as tachycardia and hypotension.
Check the venipuncture site in 5 minutes for
hematoma formation. If the client is immunosuppressed, check the puncture site every 8 hours for
signs and symptoms of infection or septicemia,
such as fever, chills, petechiae, and inflamed
joints.
Monitor vascular device or catheter insertion site
for redness, swelling, pain, and purulent drainage
indicating infection and monitor for sepsis caused
by contamination during the procedure.
If the specimen cannot be transported to the
laboratory within a reasonable time or if analysis
is delayed, arrange for proper storage to prevent
deterioration or contamination that can cause
inaccurate results.

APPENDIX

Obtaining Various Types
of Urine Specimens
One of the main reasons for invalid results of urine
tests is improper specimen collection and maintenance. Therefore, the nurse must know how the
specimens are collected and how to instruct clients
on specimen collection. The various types of specimens are discussed here.

RANDOM SPECIMENS
Random specimens are urine samples that are
collected at any time of day in clean containers.
Usually 15 to 60 mL of urine is sufficient for tests
performed on random samples. Random samples
are used for routine screening tests to detect obvious
abnormalities. The client is instructed to void
directly into the urine container or to void in some
other type of clean container, after which the sample
is transferred to another type of laboratory
container. If the sample is collected by the client at
home, it must be transported to the laboratory
within 2 hours or test results may be inaccurate.

FIRST MORNING SPECIMENS
First morning specimens are collected upon arising
in the morning, when urine is most concentrated.
Such samples are ideal for screening purposes,
because substances may be detectable in them that
are not found in more dilute samples. In addition to
routine screening tests, first morning samples are
desirable for pregnancy tests and tests for orthostatic proteinuria.

DOUBLE-VOIDED SPECIMENS
Double-voided specimens are used when testing

urine for sugar and acetone. The purpose of this
approach is to ensure that the urine tested is fresh so
that it serves as a valid indicator of current blood
glucose and ketone levels. The client is instructed to
empty the bladder and, if possible, to drink a glass of
water. Approximately 30 minutes later, the client
voids again. The second sample is then tested. Some
individuals advocate testing the first sample as well,
in case the client cannot void a second time. The
validity of results on the first sample may be questionable, however. The double-voided specimen is
particularly critical for the first urine sample of the
day because urine that has accumulated in the bladder overnight is not a valid indicator of current
status.

CLEAN-CATCH MIDSTREAM
SPECIMENS
Clean-catch midstream specimens are used to avoid
contamination of the sample with urethral cells,
microorganisms, and mucus. The procedure is as
follows: The client is provided with a clean-catch kit
containing a sterile specimen container and materials for cleansing the meatus. The male client should
cleanse the urinary meatus with the agent provided
(or with soap and water), void a few milliliters of
urine into the toilet or urinal, and then void directly
into the specimen container. Women should cleanse
the labia minora and meatal orifice carefully, working from front to back, and then manually keep the
labia separated while voiding a few milliliters into
the toilet or bedpan. With the labia still separated,
the client should then void directly into the collection container. If a woman is menstruating or has a
heavy vaginal discharge, she should insert a clean
631

632

APPENDIX II

vaginal tampon before beginning the cleansing
process. Care must be taken by all clients to avoid
touching the inside of the urine container and lid.
Clean-catch midstream urine specimens are used
primarily for microbiologic and cytologic analysis of
urine. Some individuals also advocate using this
method for specimens for routine urinalysis, especially in women, because the sample is less likely to
be contaminated with substances that alter results of
routine screening tests.

CATHETERIZED SPECIMENS
Urine specimens can be obtained from one-time
“straight” catheterizations or from indwelling Foley
catheters. “Straight” catheterization is indicated
when the client is unable to void for a random or a
clean-catch specimen without excessively contaminating the sample. It is also used for samples for
microbiologic and cytologic studies.
Indwelling catheters may be placed for a variety of
reasons. In some cases, they may be inserted when
serial urine specimens are needed at exact time
intervals. In other cases, the catheter is already in
place and must be used for urine sampling.
When obtaining a sample from an indwelling
catheter, be sure that the drainage tube is empty;
then clamp the tube distal to the specimen collection
port. The sample is obtained with a needle (25- to
21-gauge) and a 3- to 5-mL (larger if a greater
amount is needed) syringe after the tubing has been
clamped for approximately 15 minutes. The specimen port is cleansed with an antiseptic swab (e.g.,
alcohol sponge) and the sample is aspirated. The
sample is then placed in a sterile container or
rubber-stoppered test tube and sent promptly to the
laboratory. Bedside screening tests (e.g., for glucose
and ketones) may be performed by instilling the
sample directly from the syringe to the reagent strip.
Care must be taken to ensure that the catheter is
unclamped after the sample is obtained.

TWENTY-FOUR-HOUR (TIMED)
SPECIMENS
Twenty-four-hour specimens allow quantification of
substances in urine. Methods of preserving the accumulating sample vary among laboratories and,
therefore, the laboratory should be consulted for
advice regarding the use of a preservative or the need
for refrigeration, or both. It is critical that all urine
excreted during the 24-hour period be collected.
When a 24-hour specimen is required, it is desirable to begin in the morning, usually sometime
between 6 and 8 AM. First the client voids and

discards the specimen. The collection begins when
the discard sample is obtained. All urine voided
thereafter is collected. The next day, at the same time
the specimen collection began, the client is
instructed to void again. This final voiding is added
to the sample, and the collection ends. The dates and
times of specimen collection should be noted on the
laboratory slip. In the hospital setting, it is helpful if
a reminder to collect all urine is posted in or near the
client’s bathroom so that neither the client nor the
hospital personnel inadvertently discard any portion
of the specimen. The client should be instructed
not to place toilet paper in the specimen container
(devices that fit into toilet seats are often used).
Individuals who use a bedpan should be instructed
not to void into a pan containing feces.
Sometimes it is necessary to insert a Foley
catheter for 24-hour urine collections, especially if
the client is unable to participate in specimen collection. Other times, a Foley catheter may already be in
place. When a 24-hour urine collection is to be
obtained via an indwelling catheter, the collection
should begin by changing the tubing and drainage
bag so that a clean, fresh system is in use. If a preservative is required, it can be obtained from the laboratory and placed directly into the drainage bag.
Others advocate using a container with preservative
and emptying the drainage bag contents into it at
frequent intervals (e.g., every 2 hours). If refrigeration of the specimen is necessary, the drainage bag is
placed in a basin filled with ice. The ice supply must
be renewed frequently to ensure that the specimen is
properly chilled. If the urine must be protected from
light, the drainage bag may be covered with dark
plastic or with aluminum foil. If the drainage tubing
is positioned correctly for continuous drainage, it
need not be covered.
When the collection is completed, the sample
should be transported promptly to the laboratory.
Some urine tests require 2-hour samples. A 2-hour
sample is collected in the same manner as a 24-hour
sample, with the exact starting and stopping times
noted.

SUPRAPUBIC ASPIRATION
Suprapubic aspiration involves inserting a needle
directly into the bladder to obtain a urine sample.
Because the bladder is normally sterile, this method
allows collection of samples that are free of extraneous contamination. In this procedure, the skin over
the suprapubic area is cleansed with antiseptic and
draped with sterile drapes. A local anesthetic may
then be injected. The needle is inserted and the
sample is removed, after which a sterile dressing is

OBTAINING VARIOUS TYPES OF URINE SPECIMENS

applied. The site is observed for inflammation and
abnormal drainage. Suprapubic aspiration may be
used for samples for microbiologic and cytologic
analysis. It may also be used to obtain samples in
infants and young children.

PEDIATRIC SAMPLES
Pediatric urine collections can be performed for
random, first voided, clean-catch, or timed specimens. For infants, this procedure involves the
attachment of a plastic collection device to the male
penis or to the female genitalia to collect the urine. A
female infant is placed in a supine position with the
hips rotated and abducted and the knees flexed. The
perineal area is cleansed and dried, and the collection device is taped to the perineum at the point
between the anus and the vagina. The adhesive edges
of the device toward the front and over the pubic
area are sealed to prevent leakage of urine. A male
infant is placed in supine position, and the penis and
scrotum are cleansed and dried. The device is
applied over the penis and scrotum and the edges are
sealed against the perineum to prevent leakage of
urine. A diaper is placed over the collection device.
The device is removed after the specimen is obtained

633

to prevent loosening of a moist bag. The urine is
placed in a clean container, labeled correctly, and
sent to the laboratory. A clean-catch specimen is
collected using the same appliances applied after
cleansing with soap or an antiseptic pad and then
with sterile water. The specimen should be tested
immediately for accurate results, because the
number of bacteria can double every 20 to 30
minutes. If the infant has not voided within 45
minutes, the bag is removed and the cleansing and
application are repeated. A 24-hour specimen collection requires a special collection bag that contains a
collection tube attached to a container device that
can be emptied periodically. Testing with Tes-Tape
can be accomplished by placing a cotton ball in the
diaper to collect the urine and placing the tape on
the wet cotton ball. The wet diaper can also be used
for this type of testing. Urine specimens are obtained
from toilet-trained children in the same manner as
for adults. It is helpful to follow the child’s usual
urinary pattern when collecting the specimen. A
potty chair or bedpan placed on the toilet and terminology familiar to the child should be used (“tinkle,”
“potty,” and so on). A parent can assist and often has
more success in collecting a specimen than does a
nurse.

APPENDIX

Guidelines for Isolation
Precautions in Hospitals*
INTRODUCTION

In 1996, the Centers for Disease Control and Prevention (CDC) revised
its Guidelines for Isolation Precautions in Hospitals to meet the following objectives: (1) to be
epidemiologically sound; (2) to recognize the importance of all bodily fluids, secretions, and
excretions in the transmission of nosocomial pathogens; (3) to contain adequate precautions
for infections transmitted by the airborne, droplet, and contact routes of transmission; (4) to
be as simple and user friendly as possible; and (5) to use new terms to avoid confusion with
existing infection control and isolation systems.
The revised guidelines contain two tiers of precautions. The first and most important
precautions are those designed for the care of all patients regardless of their diagnosis or
presumed infection status. These standard precautions are designed to prevent the occurrence
of nosocomial infections. The second tier is designed to implement isolation precautions for
specific patients with certain diagnoses. Included are airborne, droplet, and contact modes of
transmission.

STANDARD PRECAUTIONS
(TIER ONE)
1. Standard precautions apply to all blood, bodily
fluids, secretions, excretions, nonintact skin,
and mucous membranes.
2. Handwashing is to be done between all client
contacts, and after contact with blood, bodily
fluids, secretions, excretions, or contaminated
equipment.
3. Gloves are worn at all times when in contact
with blood, bodily fluids, secretions, excretions, nonintact skin, and mucous membranes. Handwashing is to be done after
removal of gloves.
4. Masks and eye protection are worn if splashing
of blood or bodily fluids is possible.

5. Gowns are worn if contact with blood, bodily
fluids, secretions, or excretions is possible.
6. Proper disinfection of equipment is necessary,
and single-use items should be used and properly disposed of after use.
7. Contaminated linens are to be placed in
leakproof bags and appropriately tagged.
8. Sharp instruments and needles are to be
disposed of in a puncture-resistant container.
This container should be placed in every client
room. The CDC recommends that needles be
disposed of uncapped or that a mechanical
device be used for recapping.
9. Private rooms are generally not necessary
unless client hygiene practices are inadequate
or in cases of specific Tier Two situations.

* Adapted from Centers for Disease Control and Prevention (http://www.cdc.gov).
Author’s Note: This is an excellent web site for up-to-date information on precaution guidelines and statistical data on
infectious diseases.
634

GUIDELINES FOR ISOLATION PROCEDURES IN HOSPITALS

TRANSMISSION CATEGORIES
(TIER TWO)
Airborne Precautions
1. Droplet nuclei smaller than 5 microns
(measles, chickenpox, disseminated varicella
zoster, pulmonary or laryngeal tuberculosis).
2. Clients require a private room, negative airflow
with at least six changes per hour, and a mask
or other respiratory protection for the nurse.
The client may also require a mask if coughing
is excessive.

Droplet Precautions
1. Droplets larger than 5 microns (diphtheria,
rubella, streptococcal pharyngitis, pneumonia,

635

scarlet fever, pertussis, mumps, mycoplasma or
meningococcal pneumonia, or sepsis).
2. Private room or cohort (isolated grouping) of
clients and a mask for the nurse are required.

Contact Precautions
1. Direct client contact or environmental
contact, colonization or infection with drugresistant organisms, Shigella and other enteric
pathogens, herpes simplex, scabies, varicella
zoster.
2. Private room, cohort of clients, gloves, and
gown for the nurse are required.

APPENDIX

Units of Measurement
(Including SI Units)*
SCIENTIFIC NOTATION
Sometimes it is necessary to use very large and very small numbers. These can best be indicated and handled
in calculations by use of scientific notation, which is to say by use of exponents. Use of scientific notation
requires writing the number so that it is the result of multiplying some whole number power of 10 by a
number between 1 and 10. Examples are:
1234 1.234 103
1
0.01234 1.234
1.234 102
100
1
0.001234 1.234
= 1.234 103
1000
To convert a number to its equivalent in scientific notation:
Place the decimal point to the right of the first non-zero digit. This will now be a number between 1 and 9.
Multiply this number by a power of 10, the exponent of which is equal to the number of places the decimal point was moved. The exponent is positive if the decimal point was moved to the left, and negative if it
was moved to the right. For example:
1,234,000.0 0.000072
1.234 106 7.2 105
=
6000.0
6.0 103
Now, by simply adding or subtracting the exponents of ten, and remembering that moving an exponent from
the denominator of the fraction to the numerator changes its sign,
=

1.234 102 7.2
1.234 106 105 103 7.2
=
6
6

Now, dividing by 6,
1.234 102 1.2 1.4808 102

1.4808
0.014808
100

The last operation changed 1.4808 102 into the final value, 0.014808, which is not expressed in scientific
notation.

SI UNITS (SYSTÈME INTERNATIONAL D’UNITÉS
OR INTERNATIONAL SYSTEM OF UNITS)
This system includes two types of units important in clinical medicine. The base units are shown in the first
table, derived units in the second table, and derived units with special names in the third table.
* Adapted from Thomas, CL (ed): Taber’s Cyclopedic Medical Dictionary, ed 19. FA Davis, Philadelphia, 2000, pp 2376–2382.
Used with permission.
636

UNITS OF MEASUREMENT (INCLUDING SI UNITS)

SI Base Units
Quantity

Name

Symbol

Length

meter

Mass

kilogram

Time

second

Electric current

ampere

Temperature

kelvin

Luminous intensity

candela

Amount of a substance

mole

mol

Some SI Derived Units
Quantity

Name of Derived Unit

Symbol

Area

square meter

Volume

cubic meter

Speed, velocity

meter per second

m/s

Acceleration

meter per second squared

m/s2

Mass density

kilogram per cubic meter

kg/m3

Concentration of a substance

mole per cubic meter

mol/m3

Specific volume

cubic meter per kilogram

m3/kg

Luminescence

candela per square meter

cd/m2

SI Derived Units with Special Names
Quantity

Name

Symbol

Expressed in Terms of
Other Units

Frequency

hertz

Force

newton

kg·m·s2 or kg·m/s2

Pressure

pascal

N·m2 or N/m2

Energy, work, amount of heat

joule

kg·m2·s2 or N·m

Power

watt

J·s or J/s

Quantity of electricity

coulomb

A·s

Electromotive force

volt

W/A

Capacitance

farad

C/V

Electrical resistance

ohm

V/a

Conductance

siemens

A/V

Inductance

henry

W/A

Illuminance

lux

ln/m2

Absorbed (radiation) dose

gray

J/kg

Dose equivalent (radiation)

sievert

J/kg

Activity (radiation)

becquerel

637

638

APPENDIX IV

Prefixes and Multiples Used in SI
Prefix

Symbol

tera

Power

Multiple or Portion of a Multiple

12
9

1,000,000,000.

1,000,000,000,000.

giga

mega

106

1,000,000.

1,000.

100.

10.

0.1

0.01

kilo
hecto
deca

unity
deci
centi

1.
d
c

milli

0.001

micro

106

0.000001

0.000000001

0.000000000001

nano
pico

femto

0.000000000000001

atto

1018

0.000000000000000001

METRIC SYSTEM
Masses
Table

Grams

Grains

1 Kilogram

1000.0

15,432.35

1 Hectogram

100.0

1,543.23

1 Decagram

10.0

154.323

1 Gram

1.0

15.432

1 Decigram

0.1

1.5432

1 Centigram

0.01

0.15432

1 Milligram

0.001

0.01543

15.432 106

1 Microgram

1 Nanogram

109

15.432 109

15.432 1012

1 Picogram

1 Femtogram

1015

15.432 1015

1 Attogram

1018

15.432 1018

Arabic numbers are used with masses and measures, as 10 g, or 3 ml, etc. Portions of masses and measures are
usually expressed decimally. 101 indicates 0.1; 106 0.000001; etc. SEE: Scientific Notation Appendix.

UNITS OF MEASUREMENT (INCLUDING SI UNITS)

639

WEIGHTS AND MEASURES
Arabic numerals are used with masses and measures, as 10 g, or 3 ml, etc. Portions of masses and measures are
usually expressed decimally. For practical purposes, 1 cm3 (cubic centimeter) is equivalent to 1 ml (milliliter)
and 1 drop (gtt.) of water is equivalent to a minim (m).

Length
Millimeters (mm)

Centimeters (cm)

Inches (in)

Feet (ft)

Yards (yd)

Meters (m)

1.0

0.1

0.03937

0.00328

0.0011

0.001

10.0

1.0

0.3937

0.03281

0.0109

0.01

25.4

2.54

1.0

0.0833

0.0278

0.0254

304.8

30.48

12.0

1.0

0.333

0.3048

914.40

91.44

36.0

3.0

1.0

0.9144

39.37

3.2808

1.0936

1.0

1000.0

100.0

1 m 1 micrometer 0.001 millimeter. 1 mm 100 m.
1 km 1 kilometer 1000 meters 0.62137 statute mile.
1 statute mile 5280 feet 1.609 kilometers.
1 nautical mile 6076.042 feet 1852.276 meters.

Volume (Fluid)
Milliliters
(ml)

US
Fluidrams (f )

1.0

0.2705

3.697
16.3866

Cubic
Inches (in3)

U.S.
Fluidounces (f )

U.S.
Fluid Quarts (qt)

0.061

0.03381

0.00106

0.001

1.0

0.226

0.125

0.00391

0.00369

4.4329

1.0

0.5541

0.0173

0.01639

29.573

8.0

0.03125

0.02957

946.332

256.0

57.75

32.0

1.0

0.9463

270.52

61.025

33.815

1.0567

1.0

1000.0

1.8047

1.0

Liters (L)

1 gallon 4 quarts 8 pints 3.785 liters.
1 pint 473.16 ml.

Weight
Grains (gr)
1.0
15.432
480.0
7000.0
15432.358

Apothecaries’
Ounces (f )

Avoirdupois
Pounds (lb)

Kilograms (kg)

0.0648

0.00208

0.0001429

0.000065

1.0

0.03215

0.002205

0.001

1.0

Grams (g)

31.1
453.5924
1000.0

0.06855

0.0311

14.583

1.0

0.45359

32.15

2.2046

1.0

1 microgram (g) 0.001 milligram.
1 mg 1 milligram 0.001 g; 1000 mg 1 g.

640

APPENDIX IV

APOTHECARIES’ WEIGHT
20 grains 1 scruple
8 drams 1 ounce

3 scruples 1 dram
12 ounces 1 pound

AVOIRDUPOIS WEIGHT
27.343 grains 1 dram
16 ounces 1 pound
2000 pounds 1 short ton
1 oz troy 480 grains
1 lb troy 5760 grains

16 drams 1 ounce
100 pounds 1 hundredweight
2240 pounds 1 long ton
1 oz avoirdupois 437.5 grains
1 lb avoirdupois 7000 grains

CIRCULAR MEASURE
60 seconds 1 minute
90 degrees 1 quadrant

60 minutes 1 degree
4 quadrants 360 degrees circle

CUBIC MEASURE
1728 cubic inches 1 cubic foot
2150.42 cubic inches 1 standard bushel
1 cubic foot about four fifths of a bushel

27 cubic feet 1 cubic yard
268.8 cubic inches 1 dry (U.S.) gallon
128 cubic feet 1 cord (wood)

DRY MEASURE
2 pints 1 quart

8 quarts 1 peck

4 pecks 1 bushel

LIQUID MEASURE
16 ounces 1 pint
1000 milliliters 1 liter
4 gills 1 pint

4 quarts 1 gallon
31.5 gallons 1 barrel (U.S.)
2 pints 1 quart

2 barrels 1 hogshead (U.S.)
1 quart 946.35 milliliters
1 liter 1.0566 quart

Barrels and hogsheads vary in size. A U.S. gallon is equal to 0.8327 British gallon; therefore, a British gallon is
equal to 1.201 U.S. gallons. 1 liter is equal to 1.0567 quarts.

LINEAR MEASURE
1 inch 2.54 centimeters
12 inches 1 foot
1 statute mile 5280 feet

40 rods 1 furlong
3 feet 1 yard
3 statute miles 1 statute league

8 furlongs 1 statute mile
5.5 yards 1 rod
1 nautical mile 6076.042 feet

TROY WEIGHT
24 grains 1 pennyweight

20 pennyweights 1 ounce
Used for weighing gold, silver, and jewels.

12 ounces 1 pound

HOUSEHOLD MEASURES AND WEIGHTS
Approximate Equivalents: 60 gtt. 1 teaspoonful 5 ml 60 minims
60 grains 1 dram 1/8 ounce
1 teaspoon 1/8 fl. oz; 1 dram
16 teaspoons (liquid) 1 cup
3 teaspoons 1 tablespoon
12 tablespoons (dry) 1 cup
1 tablespoon 1/2 fl. oz; 4 drams
1 cup 8 fl. oz
1 tumbler or glass 8 fl. oz; 1/2 pint
* Household measures are not precise. For instance, a household tsp will hold from 3 to 5 ml of liquid. Therefore, household
equivalents should not be substituted for medication prescribed by the physician.
Note: Traditionally, the word weights is used in these tables, but masses is the correct term.

UNITS OF MEASUREMENT (INCLUDING SI UNITS)

641

CONVERSION RULES AND FACTORS
To convert units of one system into the other, multiply the number of units in column I by the equivalent
factor opposite that unit in column II.

WEIGHT
1 attogram
1 femtogram
1 picogram
1 nanogram
1 microgram
1 milligram
1 centigram
1 decigram
1 decagram
1 hectogram
1 gram
1 gram
1 gram
1 gram
1 kilogram
1 kilogram
1 kilogram
1 grain
1 grain
1 apothecaries’ dram
1 avoirdupois ounce
1 apothecaries’ or troy ounce
1 avoirdupois pound

15.432 1018 grains
15.432 1015 grains
15.432 1012 grains
15.432 109 grains
15.432 106 grains
0.015432 grain
0.15432 grain
1.5432 grains
154.323 grains
1543.23 grains
15.432 grains
0.25720 apothecaries’ dram
0.03527 avoirdupois ounce
0.03215 apothecaries’ or troy ounce
35.274 avoirdupois ounces
32.151 apothecaries’ or troy ounces
2.2046 avoirdupois pounds
64.7989 milligrams
0.0648 gram
3.8879 grams
28.3495 grams
31.1035 grams
453.5924 grams

VOLUME (AIR OR GAS)
1 cubic centimeter (cm3)
1 cubic meter (m3)
1 cubic meter
1 cubic inch (in.3)
1 cubic foot (ft3)

0.06102 cubic inch
35.314 cubic feet
1.3079 cubic yard
16.3872 cubic centimeters
0.02832 cubic meter

CAPACITY (FLUID OR LIQUID)
1 milliliter
1 milliliter
1 milliliter
1 liter
1 liter
1 liter
1 liter
1 fluidram
1 fluidounce
1 pint
1 quart
1 gallon

16.23 minims
0.2705 fluidram
0.0338 fluidounce
33.8148 fluidounces
2.1134 pints
1.0567 quart
0.2642 gallon
3.697 milliliters
29.573 milliliters
473.1765 milliliters
946.353 milliliters
3.785 liters

642

APPENDIX IV

TIME
1 millisecond one thousandth (0.001) of a second
1 second 1/60 of a minute

1 minute 1/60 of an hour
1 hour 1/24 of a day

TEMPERATURE
Given a temperature on the Fahrenheit scale, to convert it to degrees Celsius, subtract 32 and multiply by 5/9.
Given a temperature on the Celsius scale; to convert it to degrees Fahrenheit, multiply by 9/5 and add 32.
Degrees Celsius are equivalent to degrees Centigrade.

PRESSURE
TO OBTAIN

MULTIPLY

lb/sq in.
lb/sq in.
lb/sq in.
lb/sq in.
lb/sq in.
lb/sq in.
lb/sq in.
lb/sq ft
lb/sq ft
lb/sq ft
lb/sq ft
lb/sq ft
lb/sq ft
lb/cu in.
lb/cu ft
lb/cu ft
lb/U.S. gal
in. of water
in. of water
ft of water
ft of water
ft of water
ft of water
ft of water
atmospheres
atmospheres
atmospheres
bars
in. of mercury
in. of mercury
mm of mercury
g/ml
g/sq cm
kg/sq meter
kg/sq meter
kg/sq meter
kg/sq meter
kg/sq meter
kg/sq cm

atmospheres
in. of water
ft of water
in. of mercury
kg/sq meter
kg/sq cm
cm of mercury
atmospheres
in. of water
ft of water
in. of mercury
cm of mercury
kg/sq meter
g/ml
lb/cu in.
gm/ml
gm/L
in. of mercury
cm of mercury
atmospheres
lb/sq in.
kg/sq meter
in. of mercury
cm of mercury
ft of water
in. of mercury
kg/sq cm
atmospheres
atmospheres
lb/sq in.
atmospheres
lb/cu in.
kg/sq meter
lb/sq in.
in. of water
in. of mercury
cm of mercury
atmospheres
atmospheres

BY
14.696
0.03609
0.4335
0.4912
0.00142
14.22
0.1934
2116.8
5.204
62.48
70.727
27.845
0.20482
0.03613
1728.0
62.428
8.345
13.60
5.3543
33.95
2.307
0.00328
1.133
0.4461
0.02947
0.03342
0.9678
1.0133
29.921
2.036
760.0
27.68
0.1
703.1
25.40
345.32
135.95
10332.0
1.0332

UNITS OF MEASUREMENT (INCLUDING SI UNITS)

643

FLOW RATE
TO OBTAIN

MULTIPLY

cu ft/hr
cu ft/hr
L/min

cc/min
L/min
cu ft/hr

0.00212
2.12
0.472

PARTS PER MILLION
Conversion of parts per million (ppm) to percent:
1 ppm 0.0001%, 10 ppm 0.001%, 100 ppm 0.01%,
1000 ppm 0.1%, 10,000 ppm 1%, etc.

ENERGY
1 foot pound 1.35582 joule
1 joule 0.2389 Calorie (kilocalorie)
1 Calorie (kilocalorie) 1000 calories 4184 joules
A large Calorie, or kilocalorie, is always written with a capital C.

PH
The pH scale is simply a series of numbers stating where a given solution would stand in a series of solutions
arranged according to acidity or alkalinity. At one extreme (high pH) lies a highly alkaline solution, which may
be made by dissolving 4 g of sodium hydroxide in water to make a liter of solution; at the other extreme (low
pH) is an acid solution containing 3.65 g of hydrogen chloride per liter of water. Halfway between lies purified water, which is neutral. All other solutions can be arranged on this scale, and their acidity or alkalinity can
be stated by giving the numbers that indicate their relative positions. If the pH of a certain solution is 5.3, it
falls between gastric juice and urine on the above scale, is moderately acid, and will turn litmus red.
Tenth-normal HCl
Gastric juice
Urine
Water
Blood
Bile
Pancreatic juice
Tenth-normal NaOH

1.00
1.4
Litmus is red in this acid range
*6.0
7.00 — Neutral
7.35–7.45
*7.5
Litmus is blue in this alkaline range.
8.5
13.00

* These body fluids vary rather widely in pH; typical figures have been used for simplicity. Urine samples obtained from healthy
individuals may have pHs anywhere between 4.7 and 8.0.

APPENDIX

Profile or Panel Groupings
and Laboratory Tests
PROFILE OR PANEL GROUPINGS
OF DIAGNOSTIC PROCEDURES
A profile or panel grouping refers to a measurement
of multiple laboratory tests that reflects the function
of several organ systems (health profile) or to a
group of selected diagnostic tests and procedures
that reflects the function or status of a specific organ
or disease. In general, profiles or panels help to
determine the client’s state of health, support or rule
out the presence of physiological abnormalities,
determine the effectiveness of therapy, and provide
preventive measures or teaching to reduce the
progression of a disease. They are also used as
screening tests for asymptomatic clients as a preventive measure, although it is generally felt that
routine individual screening tests are all that are
needed for those who are healthy.
The panel or profile consists of a battery or group
of 4 to 12 biochemical tests performed on a few
milliliters of serum with an instrument called the
sequential multiple analyzer (SMA). The tests are
ordered as a unit designated as SMA-4, SMA-6, or
SMA-12. SMA-4 includes red blood cell (RBC)
count, white blood cell (WBC) count, hemoglobin
(Hgb), and hematocrit (Hct). SMA-6 includes
sodium (Na), potassium (K), chloride (Cl), bicarbonate (HCO3), glucose, and blood urea nitrogen
(BUN). SMA-12 includes total protein, albumin,
calcium (Ca), BUN, inorganic phosphorus, cholesterol, glucose, uric acid, creatinine, total bilirubin,
alkaline phosphatase (ALP), and aspartate aminotransferase (SGOT [AST]). The electrolytes
included in the SMA-6 can replace uric acid, creatinine, cholesterol, and phosphorus (P) to provide
another variety of SMA-12. Another type of
analyzer, known as SMAC, can accommodate a large
644

profile of roughly 20 tests (CHEM 20), provide
several tests from each of the panels, and analyze
components of the blood singly or in combination
to note organ or body system associations in a single
procedure. Patterns of abnormalities can be recognized by the physician, and more conclusive diagnostic procedures can be ordered based on these
profile results (Table A–2).

LABORATORY TESTS FOR
DISEASES, ORGANS, OR ORGAN
SYSTEMS
Cardiovascular System
Cardiac enzymes: Aspartate aminotransferase
(AST, SGOT), creatine phosphokinase (CPK),
creatine kinase (CK) and isoenzyme (CK-MB),
lactate dehydrogenase (LH, LDH) and isoenzyme
(LD1, LD2), hydroxybutyrate dehydrogenase
(HBDH)
Lipids: Total lipids, lipoprotein electrophoresis
(HDL, LDL, VLDL), cholesterol, triglycerides,
phospholipids
Electrolytes: Potassium (K), sodium (Na)
Coagulation: Prothrombin time (PT), activated
partial thromboplastin time (aPTT), coagulation
time (CT), clotting time, Lee-White coagulation
time(LWCT)
Pericardial fluid: Cytologic examination; other
tests to measure RBC count, WBC count, differential, and glucose; microbiologic examination if
endocarditis is suspected (Gram stain, culture)
Drug levels: Digoxin, digitoxin, diltiazem,
nifedipine, propranolol, verapamil, others
included in therapeutic regimen
Miscellaneous: Erythrocyte sedimentation rate

PROFILE OR PANEL GROUPINGS AND LABORATORY TESTS

Chem-20 Health Profile
with Some Organ Associations of
Each Analyte
TABLE A–2

Glucose F, R

Bilirubin, direct L

BUN K, L, F

Bilirubin, total L

Creatinine K, F

LDH L, M

Uric acid K

SGOT (AST) L, M

Sodium K, F

SGPT (ALT) L

Potassium K, F

Alkaline phosphatase L, B

Chloride K, F

Albumin N, L, K

Bicarbonate K, F

Total protein N, L

Calcium B, F

Cholesterol N, R

Phosphorus K, B

Triglycerides N, R

Kkidneys, Lliver, Bbone, Nnutrition,
Mmuscle, Rcardiac risk assessment, Ffluid
and electrolyte balance.
Source: Sacher, RA, and McPherson, FA: Widmann’s
Clinical Interpretation of Laboratory Tests, ed 11. FA
Davis, Philadelphia, 2000, p 20. Used with permission.

(ESR), WBC, glucose, blood gases (pH, pCO2,
pO2)
Procedures: Cardiac nuclear scanning, cardiac
radiography, echocardiography, electrocardiography (ECG), phonocardiography, exercise ECG,
cardiac catheterization and angiography, heart
and chest magnetic resonance imaging (MRI),
non-nuclear computed tomography (CT) of the
chest

Pulmonary System
Arterial blood gases (ABGs): pH, pCO2, pO2,
HCO2, BE
Sputum: Microbiologic examination (Gram and
other stains, acid-fast bacillus [AFB] smear and
culture), culture and sensitivity (C&S), cytologic
examination
Pleural fluid: Microbiologic examination (C&S,
Gram stain); cytologic examination; other tests
to measure LDH, RBC, WBC, differential,
eosinophils, pH, and immunoglobulins
Drug levels: Theophylline therapeutic regimen
Miscellaneous: 1-antitrypsin, WBC
Procedures: Bronchoscopy, mediastinoscopy,
thoracoscopy, chest radiography and tomography; bronchography; pulmonary angiography;
thoracic ultrasonography; lung nuclear scanning;
non-nuclear thoracic CT; chest MRI; pulmonary
function studies; exercise pulmonary function;
body plethysmography; sweat test; lung biopsy;

645

thoracentesis; oximetry; skin tests for allergens
and bacterial and fungal pulmonary diseases

Neurological System
Cerebrospinal fluid: Routine analysis (cell count
and differential, protein, glucose); other tests
such as enzymes, electrolytes, urea, lactic acid, and
glutamine; microbiologic examination (C&S,
Gram and AFB stains); cytologic examination;
serologic examination (neurosyphilis tests)
Drug levels: Anticonvulsants (phenobarbital,
phenytoin, primidone) and others included in
therapeutic regimen or considered for overdose in
the comatose client (prescribed and otherwise)
Miscellaneous: Electrolytes (K, Na, Cl, CO2),
glucose, alcohol, ABGs, BUN, creatinine, toxicology screen (blood and urine)
Procedures: Skull and spinal radiography; cerebral angiography; brain and cerebrospinal fluid
flow nuclear scanning; echoencephalography;
non-nuclear head, intracranial, neck, and spinal
CT scanning; head and intracranial MRI; electroneurography; evoked brain potentials; spinal
nerve root thermography; oculoplethysmography; visual-auditory and optic-acoustic nerve
tests

Hematologic System
Blood cell counts: Complete blood count (CBC),
including RBC, Hgb, Hct, RBC indices (MCV,
MCH, MCHC), WBC, WBC differential, platelet,
and reticulocyte
Blood cell types: Hgb electrophoresis, blood
typing and cross-matching, sickle cell screening
Coagulation: Bleeding time, platelet aggregation,
platelet survival, clot retraction time, capillary
fragility, PT, PTT, aPTT, whole blood clotting time
(CT), thrombin clotting time (TCT), prothrombin consumption time (PCT), factor assays,
plasma fibrinogen, fibrin split products (FSP),
euglobulin lysis
Iron deficiency: Iron, total iron-binding capacity
(TIBC), folic acid, ferritin
Hemolysis: RBC enzymes (glucose-6-phosphate
dehydrogenase [G-6-PD]), haptoglobin, indirect
Coombs’, bilirubin
Miscellaneous: Erythrocyte osmotic fragility,
ESR, WBC enzymes, T- and B-lymphocyte assay,
immunoglobulin assay
Procedures: Schilling test, bone marrow aspiration, bone marrow nuclear scanning, RBC
survival time study, platelet survival time study,
lymph node biopsy

646

APPENDIX V

Endocrine System
Thyroid tests: Calcitonin, thyroid-stimulating
immunoglobulins (TSI), thyroxine-binding globulin (TBG), triiodothyronine (T3), T3 uptake,
thyroxine (T4), free T4 index, thyroid antibodies,
thyroid-stimulating hormone (TSH)
Thyroid procedures: Thyroid nuclear scanning,
radioactive iodine uptake study, thyroid-stimulating hormone (TSH) study, thyroid Cytomel and
perchlorate suppression studies, ultrasonography,
iodine 131 scanning
Parathyroid tests: Parathyroid hormone (PTH),
calcium, phosphorus, prednisone-cortisone
suppression
Parathyroid procedures: Ultrasonography,
nuclear scanning
Pituitary tests: Growth hormone (GH), GH stimulation, growth suppression, prolactin (LTH),
adrenocorticotropic hormone (ACTH), TSH and
stimulation test, follicle-stimulating hormone
(FSH), luteinizing hormone (LH), FSH-LH challenge, antidiuretic hormone (ADH)
Pituitary procedures: Skull radiography, cerebral
angiography, nuclear brain scanning, intracranial
MRI scanning
Adrenal tests: Cortisol, ACTH, cortisol-ACTH
challenge, aldosterone, aldosterone challenge,
catecholamines, urinary hormones (cortisol,
aldosterone, 17-hydroxycorticosteroids [17OHCS], 17-ketosteroids [17-KS], 17-ketogenic
steroids [17-KGS], pregnanetriol, vanillylmandelic acid [VMA])
Adrenal procedures: Non-nuclear CT scanning,
adrenal nuclear scanning, ultrasonography,
angiography, skull radiography
Pancreas tests: Glucose, glucose tolerance (GT),
2-hour postprandial glucose, ketones, glycosylated hemoglobin, BUN, creatinine, tolbutamide
tolerance, insulin, amylase, lipase, aldolase, potassium (K), sodium (Na), glucagon, C-peptide
Pancrease procedures: Endoscopic retrograde
cholangiopancreatography (ERCP), ultrasonography, abdominal MRI scanning, pancreas nuclear
scanning, non-nuclear CT scanning

Renal-Urologic Systems
Blood tests: BUN, creatinine, electrolyte panel,
osmolality, proteins, ammonia, uric acid, renin,
aldosterone, -glutamyl transpeptidase (GGT)
Urine tests: Routine analysis, creatinine clearance, insulin clearance, protein, complement C3
and C4, tubular function (phenolsulfonphthalein
[PSP]), concentration (osmolality, specific gravity), electrolytes, C&S

Procedures: Kidney and renography nuclear
scanning; non-nuclear abdominal CT; ultrasonography; angiography; kidney, ureter, bladder
(KUB) radiography; antegrade pyelography;
retrograde urethrography, cystography, and
ureteropyelography; excretory urography (IVP);
voiding cystourethrography; pelvic floor sphincter electromyography (EMG); cystometry;
uroflowmetry and urethral pressure profile;
cystoscopy; renal biopsy

Musculoskeletal System
Muscle/bone enzymes: Aldolase; ALP; CPK; AST,
SGOT
Electrolytes: Ca
Joint tests: Rheumatoid factor (RF), ESR, antistreptolysin O (ASO), immunoglobulins (IgG,
IgM), CRP, complement C3 and C4
Synovial fluid: Routine analysis (RBC, WBC,
neutrophils, protein, glucose, crystals); other tests
such as rheumatoid factor (RA), complements
Procedures: Bone and joint radiography, arthrocentesis, arthroscopy, arthrography, myelography,
musculoskeletal MRI scanning, bone and joint
nuclear scanning, EMG, muscle biopsy

Hepatobiliary-Gastrointestinal
Systems
Liver enzymes: ALP and isoenzymes (ALP1),
alanine aminotransferase (ALT, SGPT), 5′nucleotidase (5′-N), LDH and isoenzymes
(LDH5), leucine aminopeptidase (LAP), GGT,
CPK and isoenzymes (CPK3)
Liver blood tests: Bilirubin, protein (albumin,
globulin) and protein electrophoresis, PT, cholesterol, ammonia, hepatitis B–associated antigen
and antibody tests
Liver procedures: Abdominal radiography, liver
nuclear scanning, non-nuclear CT scanning;
abdominal MRI scanning, ultrasonography,
hepatic and portal angiography, liver biopsy
Gallbladder procedures: Abdominal radiography, oral cholecystography (OCG), intravenous
cholangiography (IVC), percutaneous transhepatic cholangiography (PTC), operative cholangiography, T-tube cholangiography, biliary
ultrasonography, non-nuclear CT scanning, gallbladder and biliary system nuclear scanning,
endoscopic retrograde cholangiopancreatography
(ERCP)
Esophageal and stomach tests: Electrolyte panel,
gastrin
Esophageal and stomach procedures: Gastric

PROFILE OR PANEL GROUPINGS AND LABORATORY TESTS

analysis (macroscopic and microscopic), gastric
acidity and acid stimulation, esophagogastroduodenoscopy (EGD), gastric emptying and
gastrointestinal bleeding nuclear scanning,
gastroesophageal reflux nuclear scanning, barium
swallow, upper gastrointestinal (UGI) series, fluoroscopy, esophageal manometry and associated
tests, mesenteric angiography, esophageal or
stomach biopsy
Small and large intestine tests: Electrolyte panel,
carotene, carcinoembryonic antigen (CEA);
D-xylose absorption; lactose intolerance; fecal
analysis (occult blood, fat, culture)
Small and large intestine procedures: Duodenal
contents analysis (macroscopic and microscopic), duodenal stimulation for cholecystokinin-pancreozymin (CCK-PZ) and secretin,
abdominal radiography, colonoscopy, proctosigmoidoscopy, barium enema, Meckel’s diverticulum nuclear scanning, paracentesis, peritoneal
fluid analysis, non-nuclear CT scanning, colon
biopsy

Reproductive System
Female blood tests: Prolactin, estrogen, FSH, LH,
progesterone
Female urine tests: Pregnanediol, FSH, estrogen
Female procedures: Colposcopy, culdoscopy,
laparoscopy, hysterosalpingography, pelvic and
breast ultrasonography, mammography, breast
thermography, breast biopsy, cervical biopsy,
Papanicolaou (Pap) smear, cytologic analysis
(Barr chromatin body, chromosome analysis),
non-nuclear CT pelvic scanning
Male blood tests: Testosterone, semen analysis for
fertility, cytology analysis for chromosomal and
genetic abnormalities
Male urine tests: 17-ketosteroids (17-KS)
Male procedures: Scrotal nuclear scanning, scrotal-prostate ultrasonography, prostate biopsy
Pregnant female tests: CBC, ABO and Rh typing,
albumin, syphilis serology (rapid plasmin reagin
[RPR], Venereal Disease Research Laboratory
[VDRL]), renin, TORCH screen (toxoplasmosis,
other infections, rubella, cytomegalovirus, and
herpes simplex), human placental lactogen (hPL),
CPK, hCG, progesterone and urinary pregnanediol, enzymes (heat-stable alkaline phosphatase
[HSAP], diamine oxidase [DAO], oxytocinase),
estriol (E3) in blood and urine, endocrine panel
for hormones, hematology panel for blood cells,
coagulation, iron, folate, ESR, routine urinalysis,
cytology analysis for sex chromatin and chromosomal anomalies, amniotic fluid analysis for

647

lecithin:sphingomyelin (L:S) ratio, genetic
defects, creatinine, phosphatidylglycerol (PG),
uric acid
Pregnant female procedures: Amnioscopy,
amniocentesis, pelvimetry, contraction stress
tests, pelvic ultrasonography, fetal monitoring
(internal and external), fetoscopy
Newborn tests: TORCH, type and Rh, bilirubin,
glucose, calcium, albumin, phenylketonuria
(PKU)

Immune and Autoimmune
Conditions
Immune and autoimmune tests: T- and Blymphocyte assay; immunoblast transformation;
immunoglobulin assay (IgG, IgA, IgM, IgD, and
IgE); antinuclear antibodies (ANA); antibody
tests; uric acid; rheumatoid factor (RF); ASO titer;
CRP; protein electrophoresis for cryoglobulins;
lupus erythematosus (LE); anti-DNA, complement C3 and C4 assay; ESR; human immunodeficiency virus (HIV or AIDS) antibody tests

Infectious and Febrile Conditions
Infectious and febrile tests: Heterophil, febrile
agglutinins; blood culture analysis; culture of
other body fluids; fungal antibody tests; antistreptococcal antibody tests; viral antibody tests; other
antibody tests; differential WBC count, ESR
Infectious and febrile procedures: Abscessinflammatory nuclear scanning, gallium 67
(67GA) nuclear scanning, skin tests, chest x-ray

Tumors
Tumor marker tests: Prostate (prostatic acid
phosphatase [PAP], prostate-specific antigen
[PSA]); thyroid (calcitonin); colon, lung, breast
(carcinoembryonic antigen [CEA]); liver, testes
(-fetoprotein [AFP]); testes, trophoblastic
(hCG); ovary (CA 125); breast (CA 15-3);
pancreas; colon (CA 19-9, CA 50); lymphoma,
leukemia (lymphocyte B and T)
Other tumor tests: Oncogenes (DNA sequences
by polymerase chain reaction [PCR]), cytology
examination for B- and T-cell gene rearrangement and DNA content of tumor cells, vasoactive
intestinal peptide (VIP), squamous cell carcinoma
(SCC) antigen, tissue polypeptide antigen (TPA),
neuron-specific enolase (NSE), glycoprotein antigen (DU-PAN-2), metabolic tests (uric acid, albumin, cholesterol, triglycerides), hematologic tests
(leukocytes, platelets), endocrine tests (ADH,

648

APPENDIX V

cortisol, ACTH), isoenzymes (ALP, creatine kinase
[CK-BB], galactosyltransferase [GT II], LD1),
electrolyte panel, and other tests based on
suspected tumor location
Tumor procedures: Radiography of suspected
area, lymph node and retroperitoneal ultrasonography, mammography, bone marrow aspiration,
nuclear body scanning (67Ga), non-nuclear CT
scanning of body and head, body and
head/intracranial MRI scanning, endoscopy of
area, lymphangiography, biopsy of affected organ

Chronic Disorders
Hypertension: Lipid panel (total lipids, HDL,
LDL, cholesterol, triglycerides, phospholipids),
glucose, ABGs, electrolyte panel, BUN, creatinine,
creatinine clearance, uric acid, LDH, aldosterone
(blood and urine), catecholamines, CBC, renin,
angiotensin-converting enzyme, urinalysis
Diabetes: Blood and urine glucose and ketones:
2-hour postprandial, glucose tolerance (GT),
triglycerides, glucagon, CBC, glycosylated hemoglobin, urinalysis, insulin assay

Arthritis: ANA, RF, ASO titer, CRP, protein electrophoresis, uric acid, C4 and total complement,
immune complex assay, synovial fluid analysis
Chronic obstructive pulmonary disease: Spirometry, theophylline level, ABGs, electrolyte panel,
sputum culture, chest x-ray, pulmonary function
Coronary artery disease: Glucose, lipid panel
(see Hypertension entry above), electrolyte panel
Chronic heart failure: Digoxin and other cardiac
drug levels, coagulation profile (bleeding and
clotting time, PT, PTT, and thrombin time; factor
analysis; platelets), cardiac enzymes and isoenzymes (CK, GGTP, SGOT, SGPT, LD), CBC, electrolyte panel, ESR, ECG, cardiac radiography,
angiography, echocardiography
Anemia: Schilling test, iron, TIBC, ferritin, folate,
CBC, bone marrow analysis
Drug abuse: Opiates (meperidine [Demerol],
codeine), heroin, cocaine, amphetamines, barbiturates, methaqualone, cannabinoids (marijuana,
hashish), phencyclidine (“angel dust”), phenothiazines, tricyclic antidepressants

APPENDIX

Nursing Care Plan
for Individuals
Experiencing Laboratory
and Diagnostic Testing
Diagnosis. Anxiety related to insufficient knowledge of laboratory and diagnostic testing.
Goal. Individual will verbalize feelings regarding
upcoming testing.
Interventions. Introduce yourself and other
health-care team members to the individual and
family.
Encourage individual to voice concerns and ask
questions regarding the procedures.
Permit family members to be present for support
as is possible.
Provide the following information:
Description of the test
Purpose of the test
Preprocedure routines
Who will perform the procedure and where it will
be conducted
Expected sensations
After-procedure routines
When results will be available and who will
discuss the implications
Diagnosis. Altered comfort: Pain, nausea, vomiting, diarrhea related to laboratory or diagnostic
procedure.
Goal. Increased level of comfort after symptom or
comfort relief measures are provided.

Interventions. Acknowledge the report of pain or
discomfort.
Relate how long the discomfort will last, if
known.
Provide optimal pain relief with prescribed analgesia.
Provide appropriate medications and other
nonpharmacological interventions to manage other
symptoms of discomfort.
Reduce unpleasant odors and sights as indicated.
Assess relief of pain or discomfort frequently
and provide additional measures if relief is inadequate.
Diagnosis. Risk for infection as a result of invasive
procedures.
Goal. No infection.
Interventions. Use aseptic techniques as indicated.
Change dressings as indicated; note amount and
type of drainage.
Take baseline temperature and monitor as
needed.
Assess site for redness and inflammation.
Diagnosis. High risk for bleeding related to altered
bleeding tendencies and invasive vascular procedures.

From Carpenito, L. Nursing Care Plans and Documentation: Nursing Diagnosis and Collaborative Problems, ed 2. JB
Lippincott, Philadelphia, 1995.
649

650

APPENDIX VI

Goal. Prevent acute bleeding episode.
Interventions. Assess laboratory values (platelet
count, PTT/aPTT) for bleeding tendencies.
Apply pressure to vascular site for 3 to 5 minutes
routinely.

Assess site frequently to determine appropriate
coagulation.
Apply pressure dressing as indicated.
Instruct individual and family to report continued bleeding.

Index

Note: Page numbers followed by “f ” indicate figures; those followed by “t” indicate tables.
A
Abdomen
computed tomography of, 535–536
radiography of, 404–405
obstruction series, 405
supine position for, 404f
ultrasonography of, 466–467
nursing alert, 467
ABGs. See Arterial blood gases
ABO blood typing, 96–98
Abscesses, radionuclide-mediated scanning studies of,
501–502
Acanthocytosis, characteristics and significance of, 25t
Acetylcholine receptor, antibodies to, reference values, 76t
Acetylcholinesterase (AcCHS), 157
in amniotic fluid, reference values, 302t
Acid, gastric
reference values, 316t
tests for
basal gastric acidity, 315
gastric acid stimulation, 315
Hollander insulin test, 315
Acid perfusion, esophageal, 551
Acid phosphatase (ACP)
in semen, 309t
serum, 149–150
Acid–base balance. See also pH
blood gases in, 22
hemoglobin and, 22
Acid-fast bacillus (AFB)
CSF culture for, 279–280
of peritoneal fluid, 290
sputum culture for, 272
Acidosis, blood gases in, 200t
Acoustic admittance tests, 599–601
Acoustic reflexes, reference values, 600
ACP. See Acid phosphatase
Acquired immunodeficiency syndrome (AIDS) tests, 86t,
88–89
ACTH. See Adrenocorticotropic hormone
Activated partial thromboplastin time (aPTT), 51
reference values, 51t
Acute myocardial infarction (AMI), enzymatic markers of,
152–156, 153–154t

aspartate aminotransferase, 141–142
creatine phosphokinase, 151
-hydroxybutyric dehydrogenase, 157
myoglobin, 152
troponin, 154–155
Addis count, 230
Addison’s disease
cortisol levels in, 178
urine enzyme studies and, 253, 254
Adenosine diphosphate (ADP), in platelet function, 39, 46
ADH. See Antidiuretic hormone
Adrenal angiography, 443–444
Adrenal glands
cortex, antibodies to, reference values, 76t
hormones of, 177–182; see also Aldosterone;
Catecholamines; Cortisol
radionuclide-mediated scanning studies of, 493–494
tests and procedures, profile/panel groups, 646
Adrenocorticotropic hormone (ACTH), 164–166, 177
aldosterone secretion and, 179
challenge tests, 178–179
metabolic effects, 105t
pregnanetriol and, 254
reference values, 164t
AFB. See Acid-fast bacillus
AFP. See -Fetoprotein
A-G ratio. See Albumin-to-globulin ratio
Agglutination test, for fungal and parasitic infections, 78t
AIDS tests. See Acquired immunodeficiency syndrome
tests
Alanine aminotransferase (ALT), 140–141
in cerebrospinal fluid, 276
Albumin, serum, reference values, 117t
Albumin-to-globulin (A-G) ratio, 114–116
in cerebrospinal fluid, 276, 277t
Alcohol
toxic blood levels, 216t
urine testing for, 266
Aldolase, serum, 150–151
Aldosterone, 179–180
challenge tests, 180–181
urinary, 252
indications for measuring, 259
reference values, 257t
651

652

INDEX

Alkaline phosphatase (ALP)
clinical associations, 91t
leukocyte, 37–38
reference values, 38t
serum levels, 142–143
conditions associated with elevation of, 143t
Alkaline phosphatase isoenzymes, serum levels, 144–146
-glutamyl transpeptidase, 145–146
leucine aminopeptidase, 144–145
5′-nucleotidase, 144
Alkalosis, blood gases in, 200t
Alkaptonuria, 262
Allen test, 209
Allergens, skin tests for, 615–616
intradermal tests, 617–618
patch test, 617
scratch test, 616–617
ALP. See Alkaline phosphatase
ALT. See Alanine aminotransferase
Amenorrhea, progesterone in evaluation of, 168
AMI. See Acute myocardial infarction
Amino acids, urinary, 261, 262
reference values, 263t
Aminolevulinic acid (ALA), urinary, 247
reference values, 249f
Ammonia, serum
causes of altered levels of, 124t
test for, 123
Amniocentesis, 303
Amnioscopy, 388–389
Amniotic fluid
analysis of, 297–304
for fetal maturity, 300–302
for genetic and neural tube defects, 298–299
for hemolytic disease of newborns, 299–300
indications for, 302–303
procedure and nursing care for, 303
formation of, 297
gross characteristics of, 297
reference values, 302t
Amylase
in plural fluid, 287t
serum, 147–148
causes of elevated levels of, 147t
urinary, 250
indications for testing, 251
reference values, 251t
testing procedure, 252
Anal cultures, 358–359
Anaphylactic shock, after immune competence testing, 619
Anemia(s)
chronic, profile and panel groupings, 648
classification of, 23t
hemoglobin determinations in, 22
hemolytic, classifications of, 519t
reticulocytosis in, 10
Anergy panel, 62
Angiography
adrenal, 443–444
cardiac, 440–443
catheters used in, 439f
cerebral, 444–446
conventional film, 439
distal subtraction, 439–440
fluorescein, 451–452
hepatic and portal, 447–449
lower extremity, 454–456

lymphangiography, 451–453
magnetic resonance imaging, 539–540
mesenteric, 450–451
procedures, 440
pulmonary, 446–447
renal, 449–450
risks of, 440
upper extremity, 453–454
Angiotensin, 158
Anion gap, in serum electrolytes, 198–200
Anisocytosis, characteristics and significance of, 25t
Anorectal fissure, GI bleeding in, 327
Antegrade pyelography, 424–426
Antibiotics, therapeutic vs. toxic blood levels, 214t
Antibodies. See also Immunoglobulins
in ABO blood groups, 97t
antinuclear, 75t
cell and tissue-specific, 77t
to sperm, 307–308
Antibody tests
autoantibody, 74
drugs causing false-positive reactions in, 78t
reference values, 76
for bacterial infection, 80
staphylococcal tests, 80–81
streptococcal tests, 81–82
fluorescent treponemal antibody test, 281
fluorescent treponemal antibody-absorption test,
83–84
for fungal infection, 78
immunologic, 77–78
for parasitic diseases, 78t
Anticonvulsants, therapeutic vs. toxic blood levels, 214–215t
Antidiuretic hormone (ADH), 170–171
reference values, 170
serum osmolality and, 206
Anti-DNAase B test, 80t
Antigens
in ABO blood groups, 96, 97t
lymphocyte responses to, 67f
Antigen-specific transformation tests, reference values, 67t
Antiglobulin tests
direct (DAT), 99–100
drugs causing positive results in, 100t
indirect (IAT), 100–101
reference values, 76t
Anti-hyaluronidase (AH) titer, 81
Antimitochondrial antibodies
diseases associated with, 77t
reference values, 76t
Antinuclear antibodies (ANA), 75t
reference values, 76t
Antiparietal cell, anti-intrinsic factor antibodies
diseases associated with, 77t
reference values, 76t
Anti-streptokinase (anti-SK) titer, 81
Antistreptolysin O (ASO) titer, 8ot, 81
Antithrombin system, 41–42
1-Antitrypsin test, 116–118
Anxiety, nursing goals and interventions, 649
Aortic ultrasonography, 466–468
nursing alert, 467
Apatite crystals, in synovial fluid, 293t
aPTT. See Activated partial thromboplastin time
Arterial blood gases (ABGs), 207–210
components of, 207–208
procedure for, 209

INDEX

in pulmonary function studies, 588
reference values, 208t
Arterial Doppler ultrasound
carotid studies, 478–479
extremity studies, 477–478
nursing alert, 478
transcranial studies, 479–480
Arterial plethysmography, 552–553
Arteries
of abdomen, 450f
coronary, 441f
of hand and wrist, 454f
head and facial, 445f
hepatic, 450f
of leg and foot, 455f
pulmonary, catheterization of, 582–583
Arthritis, profile/panel groups, 648
Arthrocentesis, 295
Arthrography, 431–432
Arthroscopy, 394–396
of knee, 394f
Arylsulfatase A, urinary, 250, 251
indications for testing, 251
reference values, 251t
testing procedure, 252
Ascites, 290
ASO. See Antistreptolysin O titer
Aspartate aminotransferase (AST), 141–142
conditions affecting serum levels, 141t
Aspirin
gastric mucosal affects, 312
hemostasis and, 40
therapeutic vs. toxic blood levels, 216t
Audiometry, 596–598
Békésy, 603t, 604
Auditory brainstem electric response, 604
reference values, 603
Autoantibody tests, 74
drugs causing false-positive reactions in, 78t
reference values, 76
Autoimmune disorders
abnormal T-cell subsets in, 63t
helper–suppressor cell imbalance in, 61t
profile/panel groupings and tests, 647

B
B lymphocytes, 61
antigen response of, 67f
assays of, 62–64, 66
causes of altered levels of, 63t
function of, 33, 62
reference values, 16t, 64t
Bacteria. See also Culture and sensitivity tests
antimicrobial susceptibility of, 352–353
in duodenal secretions, 317
in feces, 329–330
in gastric secretions, 313
in septicemia, 353
in sputum, 271
in urine, 232
nitrite analysis and, 230
Bacterial infection antibody tests, 80
staphylococcal tests, 80–81
streptococcal tests, 81–82

653

Bands
reference values
in bone marrow, 8t
in CBC, 16t
in WBC, causes of altered levels of, 34t
Barbiturates
toxic blood levels, 216t
urine testing for, 266
Barium enema, 416–417
nursing alert, 417
Barium swallow, 413–414
in cardiac films, 409
Basal gastric acidity test, 315
procedure, 316
Base excess, definition of, 207
Basophils
causes of altered levels of, 35t
function of, 32
reference values, 16t
stippling, causes of, 26t
Békésy audiometry, 603t, 604
Bence Jones protein, 262
reference values, 263t
Bicarbonate
in duodenal secretions, 317
ion concentration, in arterial blood gases, 208, 209t
serum, 198
disorders and drugs associated with altered levels of,
199t
Bile
in feces, 328
indications for testing, 329
pigments, 228
Bile duct
common, T-tube placement in, 421f
needle placement for PTHC in, 421f
Bilirubin
amniotic, 299–300, 301
reference values, 302t
serum
indirect and direct, causes of elevations in, 138t
reference values, 138t
tests for, 137–139
urinary, 228–230
reference values, 249f
Binaural loudness balance, 604
reference values, 603
Binaural midplane localization, 604
reference values, 603
Biomicroscopy, slit-lamp, 611–612
Biopsy
bladder/ureter, 338–339
bone, 335–336
breast, 336–337
cervical punch, 337–338
chorionic villus, 341–342
intestinal, 345–347
liver, 342–344
nursing alert, 343
lung, 347–348
nursing alert, 347
lymph node, 344–345
muscle, 344
needle types, 333f
Papanicolaou smear, 332–334
pleural, 348–349
nursing alert, 349

654

INDEX

Biopsy (Continued)
prostate, 349–350
renal, 339–341
skin, 335
thyroid gland, 350–351
Bladder
biopsy of, 338–339
neurogenic, types and effects of, 546t
ultrasonography of, 471–472
Blastomycosis, skin test for, 622–623
Bleeding
after antegrade pyelography, 426
after bronchoscopy, 371
after colonoscopy, 383
after esophagogastroduodenoscopy, 376
after laryngoscopy, 367
after liver biopsy, 343
after lung biopsy, 347
after PT testing, nursing care, 51
after thoracoscopy, 373
gastrointestinal, 326–327t
scanning studies, 504–505
high-risk patients for, nursing goals and interventions,
649–650
Bleeding time, 44–46
prolonged, causes of, 45t
Blood
coagulation studies, 49–59
activated partial thromboplastin time, 51–52
euglobulin lysis time, 58–59
factor assays, 55–57
fibrin split products, 58
partial thromboplastin time, 51–52
plasma fibrinogen, 57–58
prothrombin consumption time, 54
prothrombin time, 49–51
thrombin clotting time, 53–54
whole blood clotting time, 52–53
culture and sensitivity testing, 353–354
nursing alert, 354
in duodenal secretions, 317
erythrocyte studies, 19–32
functions of, 3
in gastric secretions, 313
glucose levels, 105–108
causes of alterations in, 106t
glucose tolerance tests, 105–109
hormones influencing, 105t
2-hour postprandial test, 108–109
reference values, 107t
hematopoiesis, 4–7, 5f
evaluation of, 3–38
hepatobiliary-gastrointestinal system tests, profile/panel
groups, 646
leukocyte studies, 32–38
occult, in feces, 325
conditions associated with, 326–327t
indications for testing, 329
reference values, 328t
platelet studies, 42–49
radionuclide-mediated laboratory studies of, 516–527
plasma volume, 517
platelet survival time, 520–521
RBC survival time, 517–520
red blood cell survival time, 517–520
total blood volume, 516–517
renal-urologic tests, profile/panel groups, 646

reproductive system tests, profile/panel groups, 647
sample collection, 625–626
arterial, for blood gases, 209
capillary puncture, 626
by indwelling devices and catheters, 629–630
nursing alert, 625
percutaneous umbilical cord sampling, 625
vacuumized tubes for, 628t
venipuncture, 626–627
in sputum, 269
in urine, 228
Blood chemistry, 103–220
arterial blood gases, 200t, 207–210
in acid–base imbalance, 200t
collection procedure, 209
bilirubin, 137–139
binding proteins, 118–120
ceruloplasmin, 119–120
haptoglobin, 118–119
carbohydrates, 104–113
drugs, 213–220
therapeutic and toxic levels of, 214–217t
electrolytes, 191–207
anion gap, 198–200
bicarbonate, 198
calcium, 200–202
chloride, 196–197
magnesium, 204–206
osmolality, 206–207
potassium, 192–196
enzymes, 139–160
acid phosphatase, 149–150
alanine aminotransferase, 140–141
aldolase, 150–151
alkaline phosphatase, 142–143
amylase, 147–148
aspartate aminotransferase, 141–142
cholesterases, 157–158
creatine phosphokinase, 151–154
-glutamyl transpeptidase, 145–146
hexosaminidase, 156–157
-hydroxybutyric dehydrogenase, 157
isocitrate dehydrogenase, 146
lactic dehydrogenase, 155–156
leucine aminopeptidase, 144–145
lipase, 148–149
5′-nucleotidase, 144
ornithine carbamoyltransferase, 146–147
prostate-specific antigen, 150
renin, 158–160
troponin, 154–155
hormones, 160–191
adrenocorticotropic hormone, 164–166
aldosterone, 179–181
antidiuretic hormone, 170–171
calcitonin, 176
catecholamines, 181–182
cholecystokinin, 190
cortisol, 178–179
C-peptide, 189
estrogens, 182–183
follicle-stimulating hormone, 168–169
gastric inhibitory peptide, 190
gastrin, 190–191
growth hormone, 161–163
human chorionic gonadotropin, 185–186
human placental lactogen, 186–187

INDEX

insulin, 187–189
luteinizing hormone, 169–170
parathyroid hormone, 176–177
progesterone, 183–184
prolactin, 163–164
testosterone, 184–185
thyroid-stimulating hormone, 165–167
thyroxine, 171–173
triiodothyronine, 171, 173–175
lipids, 125–137
free fatty acids, 127–128
lipoprotein and cholesterol fractionation, 133–135
lipoprotein phenotyping, 135–137
phospholipids, 131–133
total cholesterol, 130–131
triglycerides, 128–130
protein metabolites, 120–125
ammonia, 123
creatine, 123–124
creatinine, 122–123
urea nitrogen, 120–122
uric acid, 124–126
proteins, 113–125
albumin-to globulin ratio, 114–116
1-antitrypsin test, 116–118
causes of altered levels in, 114t
toxic substances, 213, 216–217
toxic doses and effects of, 218–220t
trace minerals, 212–213
vitamins, 210–212
A, 210–211
C, 211
D, 212
Blood dyscrasias
drugs causing, 17–19t
Blood typing
ABO, 96–98
Rh, 98–99
Blood urea nitrogen (BUN)
causes of altered levels in, 121t
critical values, 122
reference values, 120t
Blood–brain barrier
in brain scan, 488
permeability of, in infection, 274, 276
BMD. See Bone mass density
Body plethysmography, 553–554
in pulmonary function studies, 588
Body scanning
CT, 530–531
MRI, 537–539
plethysmographic, 553–554
Bone marrow
cells, causes of alterations in, 7t
examination of, 7
indications for, 8–9
procedure and nursing care for, 9
reference values, 8t
location of active growth in, 4f
radionuclide-mediated scanning studies of, 492–493
red vs. yellow, 4
Bone mass density (BMD), dual x-ray absorptiometry in
measurement of, 408–409
Bone(s)
biopsy of, 335–336
cervical spine, 400f
cranial, 400f

655

of extremities, 408f
facial, 400f
radionuclide-mediated studies scanning studies of,
490–492
Bosinophils, reference values, 16t
Brain. See also Head and intracranial scanning
electroencephalographic studies, 569–571
evoked potentials, 571–573
positron emission tomography of, 515
radionuclide-mediated scanning studies, 487–489
reference values, 488
Breast
biopsy of, 336–337
mammography, 411–412
positron emission tomography of, 515–516
ultrasonography of, 473–474
Bronchial provocation test, 590
Bronchial-intercostal arteriography, 446
Bronchodilators, therapeutic vs. toxic blood levels, 215t
Bronchography, 432–433
nursing alert, 433
Bronchoscopy, 367–371
with fiber-optic endoscope, 367f
procedure for, 370
indications for, 368
nursing alert, 369
nursing care for, 369, 370–371
rigid, 370
Brucella infections, febrile agglutinin tests for, 82t
BUN. See Blood urea nitrogen

C
C3, 71
causes of altered levels of, 72t
Raji cell assay and, 73
reference values, 72t
C4, 71
causes of altered levels of, 72t
reference values, 72t
CA 15-3, CA 19-9, CA 50, and CA 215 cancer antigens, 92–94
Cabot’s rings, causes of, 26t
CAD. See Coronary artery disease
Calcitonin, 176
clinical associations, 91t
Calcium (Ca)
reference values, 202t
role in coagulation, 40–41
serum, 200–202
disorders and drugs associated with altered levels of,
201t
urinary, 245
Calcium pyrophosphate (CPP) crystals, in synovial fluid, 292,
293t
Cancer antigen tests, 92–94
Cancer(s)
GI bleeding in, 326t
immunologic tests related to, 91t
CA 15-3, CA 19-9, CA 50, and CA 215 cancer
antigens, 92–94
clinical associations, 91t
reference values, 94t
carcinoembryonic antigen, 92–93
-fetoprotein, 90–92
neurological, CSF cytology and, 281
Candida albicans, 232

656

INDEX

Candidin test, 618
reference values, 619
Capacity, conversion factors, 641
Capillary fragility, Rumple-Leeds test of, 48–49
Capillary puncture, 626
Carbohydrates, 104–105
utilization, in fecal analysis, 327–328
indications for, 329
Carbon dioxide (CO2)
in arterial blood gases, 210
effects on pH, 208t
Carbonic anhydrase, 22
Carboxyhemoglobin, 27
Carcinoembryonic antigen (CEA), 92–93
causes of alterations in, 93t
clinical associations, 91t
in plural fluid, 287t
Cardiac angiography
indications for, 441
procedure and nursing care for, 441–443
Cardiac catheterization, 578–582
His bundle evoked potential study, 583–585
indications for, 579–580
insertion sites and routes, 578f
nursing alert, 580
procedure and nursing care for, 580–582
pulmonary artery, 582–583
reference values, 579t
Cardiac cycle, on ECG, 559f
Cardiac drugs, therapeutic vs. toxic blood levels, 215t
Cardiac myocardial imaging, 497
Cardiovascular system
profile/panel groupings and tests, 644–645
radiologic studies, 409–410
studies of
cardiac angiography, 441–443
cardiac catheterization, 578–582
cold stimulation test, 585–586
electrocardiography, 559–562
exercise ECG, 564–565
Holter ECG, 562–563
phonocardiography, 563–564
pulmonary artery catheterization, 582–583
signal-averaged ECG, 565–566
Casts, in urine, 231–232
types and significance of, 233t
Catecholamines
blood levels, 181–182
precursors to, 255
as tumor markers, clinical associations, 91t
urinary, 254
indications for measuring, 260
reference values, 257t
Catheters
blood collection by, 629–630
urine specimen by, 230, 632
CBC. See Complete blood count
CCK-PZ tests. See Cholecystokinin-pancreozymin test
CEA. See Carcinoembryonic antigen
Centers for Disease Control and Prevention (CDC),
Guidelines for Isolation Precautions in Hospitals,
634–635
Cerebrospinal fluid (CSF)
analysis of, 274–282
cytologic, 281
indications for, 276–278
microscopic, 279–280

neurosyphilis serology, 281
procedure and nursing care for, 278–279
routine, 275–279
cell count and differential, 275–276
flow, radionuclide-mediated scanning study of, 489–490
formation of, 274
glucose in, 276
gross appearance of, 275
proteins in, 276
reference values, 277t
Ceruloplasmin (Cp)
causes of altered levels of, 119t
test for, 119–120
Cervical punch, 337–338
Cervical samples, for semen presence, 309
CH50. See Total complement
CHEM 20, 644
Chest and thoracic studies
bronchoscopy, 367–371
computed tomography scanning, 534–535
magnetic resonance imaging, 541–542
mediastinoscopy, 371–372
plethysmographic studies, 553–554
reference values, 554t
radiographic, 402–404
left lateral view, 402f
posterior-anterior view, 402f
thoracoscopy, 372–374
tomography, 410–411
ultrasonographic, 465–466
Children
bone marrow aspiration/biopsy in, 9
nuclear scanning in, 487
urine collection in, 633
venipuncture in, 627
preparation for, 626
Chloride (Cl)
serum, 196–198
disorders and drugs associated with altered levels of,
197t
urinary, 245
Cholangiography
intravenous, 419–420
operative, 422
percutaneous transhepatic, 422–424
T-tube, 420–422
Cholangiopancreatography, endoscopic retrograde
(ERCP)
indications for, 377
nursing alert, 378
procedure and nursing care for, 378–379
Cholecystography
intravenous, 419–420
oral (OCG), 417–419
indications for, 418
nursing alert, 418
procedure and nursing care for, 419
Cholecystokinin, 190
Cholecystokinin-pancreozymin (CCK-PZ) test, 319
Cholesterases, 157–158
Cholesterol, 125
fractionation, 133–135
in plural fluid, 287t
in synovial fluid, 293t
total
disorders and drugs associated with altered levels of,
131t

INDEX

reference values, 130t
test for, 130–131
Cholinergic/myasthenic crisis, 596
Chorionic villus biopsy (CVB), 341–342
Chromium 51, 486t
Chronic obstructive pulmonary disease (COPD)
bronchography in, 433
cardiac scanning in, 495
profile/panel groups, 648
Chylomicrons, 126, 133
conditions associated with altered levels of, 134t
reference values, 133t
CIC. See Circulating immune complexes
Cineangiography, 446
Cineradiography, 398
Circulating immune complexes (CIC), 73
Cisternal puncture, 279
Citrate, as anticoagulant, 40
Citric acid cycle. See Krebs cycle
Clean-catch specimen, for urinalysis, 331–332
Clot retraction test, 47–48
Clotting factors, 40t
deficiencies, states associated with, 55–56t
reference values, 56t
Coagulation, 40–41. See also Hemostatic functions, tests of
pathways of, 41f
Coagulation time (CT), 52–53
Cobalt, physiological function of, 212
Cobalt 57, 486t
Coccidioidomycosis, skin test for, 622–623
Cold agglutinin tests, 75t, 82–83
reference values, 76
Cold stimulation test, 585–586
Colonoscopy
with fiber-optic endoscope, 381f
indications for, 381
nursing alert, 382
procedure and nursing care for, 381–383
Color perception tests, 608–609
Colposcopy, 385–386
Complement fixation tests
for bacterial infections, 80t
for fungal infections, 78t
Complement system, tests of, 71
C3 and C4, causes of alteration in levels, 72t
immune complex assays, 71
serum assays, 71–73
synovial fluid analysis, 292
Complete blood count (CBC), 14
indications for, 14
procedure and nursing care for, 14, 19
reference values, 15–16t
Computed tomography (CT), 528–537
abdominal scanning, 535–536
body scanning, 530–531
head and intracranial scanning, 531–533
neck and spinal scanning, 533–534
pelvic scanning, 536–537
thoracic scanning, 534–535
Confrontation test, 608
reference values, 608
Contraction stress test, 556–557
Contrast media studies, 399, 413
adverse reactions to iodinated media, 399t
antegrade pyelography, 424–426
arthrography, 431–432
barium enema, 416–417

657

barium swallow, 413–414
bronchography, 432–433
cholangiography
operative, 422
percutaneous transhepatic, 422–424
T-tube, 420–422
hysterosalpingography, 433–434
intravenous pyelogram, 429–430
myelography, 434–436
operative cholangiography, 422
oral cholecystography, 417–419
retrograde cystography, 427–428
retrograde ureteropyelography, 428–429
sialography, 430–431
upper gastrointestinal series, 414–416
Coombs’ tests. See Antiglobulin tests
COPD. See Chronic obstructive pulmonary disease
Copper
physiological function of, 212
urinary, 264
reference values, 264t
Coproporphyrin, urinary, 247
reference values, 249f
Corneal abrasion, after tonometry, 610
Corneal staining test, 613–614
Coronary artery disease (CAD)
exercise ECG and, 564
tests, profile/panel groups, 648
Corticosteroids, in synovial fluid, 293t
Corticotropin-releasing hormone (CRH), 160
Cortisol
serum, 178
challenge tests, 178–179
metabolic effects, 105t
urinary, 252
indications for measuring, 256, 259
reference values, 257t
Cortisone glucose tolerance test (cortisone GTT), 111–112
Coumarin, 50
Cp. See Ceruloplasmin
C-peptide, 189
CPK. See Creatine phosphokinase
Cranial bones, 400f
C-reactive protein (CRP), 75t
reference values, 76t
Creatine, serum, test for, 123–124
Creatine kinase isoenzyme, as tumor marker, clinical
associations, 91
Creatine phosphokinase (CPK), serum levels, 151–154
as cardiac marker, 153t
causes of elevation in, 152t
Creatinine
amniotic, 301
reference values, 302t
serum, test for, 122–123
urinary, 261
indications for measuring, 262
reference values, 263t
Creatinine clearance test, 239–240
CRP. See C-reactive protein
Cryoglobulins, 68, 76t
reference values, 76t
Cryptococcus, in cerebrospinal fluid, 280
C&S. See Culture and sensitivity tests
CSF. See Cerebrospinal fluid
CT. See Computed tomography
Culdoscopy, 387–388

658

INDEX

Culture and sensitivity (C&S) tests, 352–359
of peritoneal fluid, 290
specimen collection requirements, 353
of synovial fluid, 292
of urine, 264
Culture(s), 352
anal, 358–359
blood, 353–354
ear, 354–355
eye, 354–355
genital, 358–359
nose, 355–356
skin, 357–358
specimen collection requirements, 353
sputum, 271
for acid-fast bacillus, 272
stool, 329–331
throat, 355–356
urine, 264–265
wound, 356–357
Cushing’s syndrome, 253
Cutler method, for ESR determination, 32t
CVB. See Chorionic villus biopsy
Cyanobalamin. See Vitamin B12
Cystic fibrosis, sweat test for, 592
Cystography, retrograde, 427–428
Cystometry, 546–548
nursing alert, 547
reference values, 546
Cystourethrography, voiding, 430
Cytology
of cerebrospinal fluid, 281
methods in, 332–333
of sputum, 271–273
of urine, 265
Cytomel suppression, 523–525
Cytoscopy, 383–385
indications for, 383–384
procedure and nursing care for, 384–385

D
DAT. See Direct antiglobulin test
Deep vein scanning, 508–509
DEXA. See Dual energy x-ray absorptiometry
Dexamethasone, 178
Diabetes mellitus
profile/panel groups, 648
urine in, 224
Diaphanography, 412
Diarrhea
GI bleeding and, 326t
types of, 330
DIC. See Disseminated intravascular coagulation
Differential white blood cell count, 34
causes of alterations in, 34–36t
reference values, 16t, 35t
Dipyridamole (Persantine), 495
Direct antiglobulin test (DAT), 99–100
Disseminated intravascular coagulation (DIC), 47
Distal subtraction angiography, 439–440
Dopamine, 181, 254
Doppler ultrasound studies, 459
areas examined and findings, 477t
arterial transcranial, 479–480
carotid artery, 478–479

procedures in, 476
venous extremity studies, 480–481
Down syndrome, fetal cell karyotyping for, 298
Drug abuse, profile and panel groupings, 648
Drugs
affecting gastric secretions, 312
affecting urine color, 223t
blood levels of, 213, 214–217t
cardiac, profile/panel groupings, 644
causing
blood dyscrasias, 17–19t
false-positive glycosuria, 227t
false-positive reactions in autoantibody tests, 78t
glycosuria, 226, 227t
hematuria, 231
prolonged bleeding time, 45
causing altered levels of
cholesterol, 131t
free fatty acids, 128t
serum bicarbonate, 199t
serum calcium, 201t
serum chloride, 197t
serum magnesium, 205t
serum phosphate, 203t
serum phosphorus, 203t
serum potassium, 194–195t
serum sodium, 193t
serum triglycerides, 129t
impairing platelet aggregation, 46t
neurological, profile/panel groupings, 645
pulmonary, profile/panel groupings, 645
therapeutic and toxic levels of, 214–217t
urine screening tests for, 265–266
Dual energy x-ray absorptiometry (DEXA), 408–409
Duke method, of bleeding time, 44, 45
procedure, 45–46
Duodenal secretions
analysis of, 317–320
indications for, 318
macroscopic, 317
microscopic, 317–318
procedure and nursing care for, 318–319
procedure and nursing care for, 318t
stimulation tests, 319
cholecystokinin-pancreozymin, 319
indications for, 320
secretin, 319
Duplex scanning, 459
areas examined and findings, 477t

E
ECG. See Electrocardiography
Echinocytosis, characteristics and significance of, 25t
Echocardiography, 460–462
indications for, 461
procedure and nursing care for, 461–462
transesophageal, 463
Echoencephalography, 462–463
Effusions
analysis of, 283–296
definition of, 283
EGD. See Esophagogastroduodenoscopy
EIA. See Enzyme-linked immunosorbent assay
Electrocardiography (ECG), 559–562
cardiac cycle, 559f

INDEX

exercise ECG, 564–565
Holter ECG, 562–563
indications for, 560–561
phonocardiography, 563–564
reference values, 560t
signal-averaged ECG, 565–566
Electroencephalography, 569–571
indications for, 570
Electrolytes
cardiac, profile/panel groupings, 644
in cerebrospinal fluid, 276
and fluid, imbalance after oral cholecystography, 419
serum, 191–207
anion gap, 198–200
bicarbonate, 198
calcium, 200–202
chloride, 196–197
magnesium, 204–206
osmolality, 206–207
potassium, 192–196
urinary, 244–247
reference values, 246
Electromyography, 567–568
pelvic floor sphincter, 566–567
Electroneurography, 568–569
Electronystagmography, 573–574
Electro-oculography, 575–576
Electrophoresis
hemoglobin, 26–29
indications for, 27
reference values, 28t
serum proteins
patterns of, 69f
reference values, 70t
Electrophysiologic studies, 558–576
electrocardiography, 559–566
electroencephalography, 569–571
electromyography, 567–568
pelvic floor sphincter, 566–567
electroneurography, 568–569
electronystagmography, 573–574
electro-oculography, 575–576
electroretinography, 574–575
evoked brain potentials, 571–573
evoked His bundle potentials, 583–585
Electroretinography, 574–575
ELISA. See Enzyme-linked immunosorbent assay
Elliptocytosis, characteristics and significance of, 25t
Endocrine system, profile/panel groupings and tests, 645
Endoscope(s)
fiber-optic, 364f
bronchoscopy with, 367f
colonoscopy with, 381f
cross-section view, 364f
esophagogastroduodenoscopy with, 374f
rigid, 364f
types of, 363
Endoscopic studies, 363–396
amnioscopy, 388
arthroscopy, 394–396
bronchoscopy, 367–371
colonoscopy, 381–383
colposcopy, 385–386
culdoscopy, 387–388
cytoscopy, 383–385
esophagogastroduodenoscopy (EGD), 372–374
laparoscopy, 389–394

659

laryngoscopy, 364–367
mediastinoscopy, 371–372
proctosigmoidoscopy, 379–381
retrograde cholangiopancreatography, 376–379
thoracoscopy, 372–374
Enzyme-linked immunosorbent assay (ELISA), 89
for fungal and parasitic infections, 78t
for hepatitis virus, 87
for HIV, 89
Enzymes
cardiac, profile/panel groupings, 644
hepatic, profile/panel groupings, 646
red blood cell, 30–31
glucose-6-phosphate dehydrogenase, 30
pyruvate kinase, 30
reference values, 30t
serum, 139–160
acid phosphatase, 149–150
alanine aminotransferase, 140–141
aldolase, 150–151
alkaline phosphatase, 142–143
alkaline phosphatase isoenzymes, 144–146
amylase, 147–150
aspartate aminotransferase, 141–142
cholinesterases, 157–158
creatine phosphokinase, 151–154
-hydroxybutyric dehydrogenase, 157
lactic dehydrogenase, 155–156
lipase, 148–149
prostate-specific antigen, 150
renin, 158–160
troponin, 154–155
terminology for, 140
in urine, 250–252
amylase, 250, 251–252
arylsulfatase A, 250, 251, 252
leucine aminopeptidase, 250, 251, 252
lysozyme, 250, 251, 252
reference values, 251t
white blood cell, 37–38
causes of alterations in, 37–38
Eosinophils
bone marrow
causes of altered levels of, 7t
reference values, 8t
causes of altered levels of, 35t
function of, 32
Epinephrine
in aldosterone challenge tests, reference values, 181t
metabolic effects, 105t
in urine, 254
reference values, 257t
Epithelial cells
in duodenal secretions, 317
in feces, 322–323
in gastric secretions, 313
in urine, 231
Epstein-Barr virus, 85–86
ERCP. See Cholangiopancreatography, endoscopic retrograde
Erythrocyte sedimentation rate (ESR), 31
causes of alterations in, 31t
reference values, 32t
Erythrocyte(s), 3
abnormal inclusions and causes, 26t
in CBC, reference values, 15t
characteristics of, 19, 22
count, 20–21

660

INDEX

Erythrocyte(s) (Continued)
reference values, 20t
in duodenal secretions, 317
in gastric secretions, 313
hematocrit, 21
reference values, 21t
hemoglobin, 21–22
reference values, 22t
osmotic fragility, 29
causes of alterations in, 29t
reference values, 29
in pericardial fluid, 285t
production of, 4–5
RBC indices, 22
in anemias, 23t
indications for, 24
reference values, 23t
stained examination, 24
abnormalities seen on, 24–25t
indications for, 25
survival time study, 517–520
nursing care, 520
procedure, 518–519
reference values, 518
in urine, 230–231
Erythropoiesis, 4–5
inadequacy of, 6
iron in, 11
Erythropoietin, 5
causes of tissue hypoxia stimulating release of, 5t
Esophageal acid and clearing, 551
Esophageal manometry, 550–552
reference values, 550t
Esophageal varices, GI bleeding in, 326t
Esophagogastroduodenoscopy (EGD), 372–374
with fiber-optic endoscope, 374f
Esophagography. See Barium swallow
Esophagus, manometric studies of, 550–552
ESR. See Erythrocytes, sedimentation rate
Estradiol (E2), 182
reference values, 183t
Estriol (E3), 182
reference values, 183t
Estrogens
blood levels, 182–183
reference values, 183t
urinary, 255
indications for measuring, 260
reference values, 258t
Estrone (E1), 182
reference values, 183t
Ethylenediaminetetra-acetic acid (EDTA), as anticoagulant,
40
Euglobulin lysis time, 58–59
Evoked potentials (EP)
brain, 571–573
His bundle, 583–585
nursing alert, 584
Excretory urogram (EUG). See Intravenous pyelogram
Exercise ECG, 564–565
in cardiac scanning, 495
nursing alert, 497
Exercise pulmonary function studies, 590–591
Extracellular fluid, disorders and drugs associated with
altered levels of, 193t
Extremities
bones of, 408f

Doppler ultrasound studies
arterial, 477–478
venous, 480–481
lower
angiography of, 454–456
arthroscopy of knee, 394f
radiologic studies of, 407–408
upper, angiography of, 453–454
Eye(s)
color perception tests, 608–609
corneal staining test, 613–614
culture and sensitivity testing, 354
electrophysiologic studies
electronystagmography, 573–574
electro-oculography, 575–576
electroretinography, 574–575
fluorescein angiography of, 451–452
plethysmographic studies of, 554–555
radiologic studies of, 401–402
refraction, 610–611
Schirmer tearing test, 612–613
slit-lamp biomicroscopy, 611–612
tonometry, 609–610
ultrasonography of, 463–464
visual acuity tests, 605–607
visual field tests, 607–608

F
Factor assays, 55–57
Falling test, 601–602
reference values, 602
Fasting blood sugar (FBS), 113
client preparation for, 101
Fats, quantitative, in feces, 327
indications for testing, 329
reference values, 328t
Fatty acids. See Free fatty acids; Nonesterfied fatty acids
FDP. See Fibrinogen degradation products
Febrile agglutinin tests, 82–83, 82t
Febrile conditions, profile/panel groupings and tests, 647
Feces
analysis of, 321–331
for bile, 328
indications for, 329
for carbohydrate utilization, 327–328
indications for, 329
microbiologic, 329–331
indications for, 331
microscopic, 321–322
indications for, 324
for occult blood, 325, 327
indications for, 329
for quantitative fats, 323, 327
indications for, 329
for trypsin, 327
indications for, 329
for urobilinogen, 328
indications for, 329
diarrhea, types of, 330
gross characteristics of, 321–322t
reference values, 324t, 328t
Ferric ammonium citrate (Geritol), 540
Ferritin, 11
reference values, 12t
serum levels, by age and sex, 11f

INDEX

Fertility, semen analysis for, 306–308
Fetoplacental adequacy, manometric studies of, 555–557
-Fetoprotein (AFP)
in amniotic fluid, reference values, 302
maternal, conditions associated with increases in,
299t
serum test for, 90–92
Fetoscopy, 390
indications for, 391
procedure for, 393
reference values, 390
Fetus
Doppler ultrasound imaging of, 459, 475–476
risks of, 460
fetal cell karyotyping, 298
hematopoiesis in, 4
marrow growth sites in, 4f
maturity of, tests for, 300–301
creatinine bilirubin, 301–302
L:S ratio, 132, 301
phosphatidyl glycerol, 301
shake test, 301
percutaneous umbilical cord blood sampling, 625
FFAs. See Free fatty acids
Fibrin split products (FPS), 58
Fibrinogen, 39
in CSF fluid, 275
plasma levels, 57–58
Fibrinogen degradation products (FDP), 39
Fibrinolytic system, 41, 58
Fishberg test, 242, 243
Florinef, 180
Flow rate, conversion factors, 643
Fludrocortisone acetate (Florinef), 180
Fluorescein angiography, 451–452
Fluorescent treponemal antibody (FTA) test, 281
Fluorescent treponemal antibody-absorption test (FTA-ABS),
80t, 83–84
Fluoroscopy, 398
in cardiac films, 409
Folic acid
blood, reference values, 13t
studies
indications for, 13
procedure and nursing care for, 13–14
Follicle-stimulating hormone (FSH), 167–168
challenge tests, 168–169
reference values, 168t
Forssman antibody, 86
FPS. See Fibrin split products
Free fatty acids (FFAs)
factors associated with altered levels of, 128t
test for, 127–128
FSH. See Follicle-stimulating hormone
FTA. See Fluorescent treponemal antibody test
FTA-ABS. See Fluorescent treponemal antibody-absorption
test
Fungal infection
antibody tests, 78, 78t
reference values in, 79
sputum culture for, 79

G
Gadopentetate dimeglumine (Magnevist), 537, 540
Gallbladder. See also Hepatobiliary system

661

procedures and tests, profile/panel groups, 646
radionuclide-mediated scanning studies of, 509–510
ultrasonography of, 469–470
Gallium 67 (67Ga) scanning, 485t, 513–514
Gastric acid stimulation test, 315
procedure, 316
Gastric acidity
reference values, 316t
tests for
basal gastric acidity, 315
gastric acid stimulation, 315
Hollander insulin test, 315
Gastric emptying scanning, 502–503
Gastric hormones, 190–191
Gastric inhibitory peptide (GIP), 190
Gastric secretions
analysis of, 311–317
indications for, 313–314
macroscopic, 312–313
microscopic, 313
procedure and nursing care for, 314–315
blood in, 313
color of, 312–313
mucus in, 313
pH, 313
reference values, 314t
Gastrin, 190–191
Gastritis, GI bleeding in, 326t
Gastrointestinal bleeding scanning, 504–505
Gastrointestinal reflux scanning, 503–504
Gastrointestinal system
abdominal CT, 535–536
abdominal films, 404–405
acidity, tests for, 315–316
endoscopic studies
esophagogastroduodenoscopy, 372–374
proctosigmoidoscopy, 379–381
GI series
lower, 416–417
upper, 414–416
profile/panel groupings and tests, 646–647
secretions, analysis of, 311–317
Gated blood pool imaging, 497
Genetic mutation, as tumor marker, clinical associations,
91
Genitalia
cultures of, 358
male, 305f
Geritol, 540
GH. See Growth hormone
GIP. See Gastric inhibitory peptide
Glaucoma, tonometry testing for, 609
Globin, 22
Globulins. See also Albumin-to-globulin ratio
serum
causes of altered levels in, 116t
reference values, 117t
thyroxine-binding, 175–176
Glucagon, 187, 189–190
metabolic effects, 105t
Glucose
blood levels, 105–108
causes of alterations in, 106t
hormones influencing, 105t
reference values, 107t
two-hour postprandial test, 108–109
in cerebrospinal fluid, 276

662

INDEX

Glucose (Continued)
in pericardial fluid, 285t
in urine, 225–226; see also Glycosuria
Glucose tolerance tests (GTTs), 109
cortisone, 111–112
intravenous, 111
oral, 109–110
nursing alert for, 110
reference values, 110t
Glucose-6-phosphate dehydrogenase (G6PD), 30
Glutamic-oxaloacetic transaminase (GOT). See Aspartate
aminotransferase
Glutamine, in cerebrospinal fluid, 276
-Glutamyl transpeptidase, 145–146
Glycosuria, 226
drugs and disorders causing, 227t
drugs producing false-positive results, 227t
Glycosylated hemoglobin, 112
Gonadotropin-releasing hormone (GnRH), 160
Gonads, hormones of, 182–187
GOT. See Aspartate aminotransferase
G6PD. See Glucose-6-phosphate dehydrogenase
Gram stain
of cerebrospinal fluid, 280
of sputum, 269
of synovial fluid, 292
Growth hormone (GH, STH, SH), 161–162
metabolic effects, 105t
reference values, 161t
stimulation tests, 162–163
nursing alert, 162
reference values, 162t
suppression test, 163
reference values, 163t
Growth hormone-inhibiting hormone (GHIH), 160
GTT. See Glucose tolerance tests
“Guidelines for Isolation Precautions in Hospitals” (Centers
for Disease Control and Prevention), 634–635
Gynecologic laparoscopy
indications for, 391
procedure for, 392–393

H
Hallucinogens, urine testing for, 266
Haptoglobin, test for, 118–119
hCG. See Human chorionic gonadotropin
HCO3-, definition of, 207
HDL. See High-density lipoproteins
Head and intracranial scanning
computed tomography, 531–533
magnetic resonance imaging, 541
Hearing loss studies
acoustic admittance tests, 599–601
audiometry, 596–598
tuning fork tests, 598–599
Heart. See also Cardiovascular system
angiography of, 440–443
arteries and large vessels of, 441f
magnetic resonance imaging of, 541–542
positron emission tomography of, 515–516
radiologic studies of, 409–410
radionuclide-mediated scanning studies, 495–498
indications for, 496
procedure and nursing care for, 497–498
reference ECG values, 560t
Heart shunt imaging, 497

Heinz bodies, causes of, 26t
Helper T cells, 61
balance with suppressor T cells, 61t
reference values, 64t
Hematocrit, 21
critical values, 21
reference values, 21t
in CBC, 15t
Hematologic system, profile/panel groupings and tests,
645
Hematology, 3–38
definition of, 3
Hematopoiesis, 4–7
evaluation of, 7
theory of, 5f
Hematopoietic function, tests of, 3–38
bone marrow examination, 7–9
complete blood count, 14–16, 19
erythrocyte studies, 19–32
iron studies, 11–13
leukocyte studies, 32–38
reticulocyte count, 9–11
Heme, 22
formation pathway, 248f
urinary porphyrins and, 247
Hemoglobin, 21–22
degradation of, 229f
developmental changes in, 27f
electrophoresis, 26–29
indications for, 27
procedure and nursing care for, 29
reference values, 28t
glycosylated, 112
molecular structure, 26
normal vs. abnormal formation of, 28f
reference values, 22
in CBC, 15t
urinary, reference values, 249f
in urine, 228
Hemoglobinopathies, 26–27
Hemolytic assays, 71
profile/panel groupings, 645
Hemolytic disease of the newborn, tests for, 299
Hemorrhage. See Bleeding
Hemorrhoids, GI bleeding in, 327
Hemostasis, 39–59
antagonists to, 41–42
definition of, 39
Hemostatic functions, tests of, 39–59
bleeding time, 44–46
clot retraction, 47–48
coagulation studies, 49
activated partial thromboplastin time, 51–52
euglobulin lysis time, 58–59
factor assays, 55–57
fibrin split products, 58
partial thromboplastin time, 51–52
plasma fibrinogen, 57–58
prothrombin consumption time, 54
prothrombin time, 49–51
thrombin clotting time, 53–54
whole blood clotting time, 52–53
platelet aggregation, 46–47
platelet count, 42–44
profile/panel groupings, 644
Rumple-Leeds capillary fragility, 47–48
Hepatitis tests, 87–88
reference values, 88t

INDEX

Hepatobiliary system
angiography of, 447–449
cholangiography
operative, 422
percutaneous transhepatic, 422–424
T-tube, 420–422
cholecystography
intravenous, 419–420
oral, 417–419
profile/panel groupings and tests, 646
radionuclide-mediated scanning studies of, 509–510
retrograde cholangiopancreatography, 377–379
Hexosaminidase, 156–157
Hiatial hernia, GI bleeding in, 326t
High-density lipoproteins (HDL), 133
conditions associated with altered levels of, 134t
reference values, 133t
His bundle evoked potential study, 583–585
nursing alert, 584
Histology. See also Biopsy
methods in, 332–333
Histoplasmosis, skin test for, 622–623
HIV. See Human immunodeficiency virus
HLA. See Human leukocyte antigen test
Hollander insulin test, 315
procedure for, 316, 317
Holter ECG, 562–563
Homovanillic acid (HMA), urinary, 255
indications for measuring, 260
reference values, 257t
Hormones, in blood chemistry
adrenal, 177–182
aldosterone, 179–180
cortisol, 179
cortisol/ACTH challenge tests, 179–180
gastric, 190–191
gastrin, 190–191
gonadal, 182–187
estrogens, 182–183
progesterone, 183–184
testosterone, 184–185
hypophyseal, 160–171
adrenocorticotropic hormone, 164–166
antidiuretic hormone, 170–171
follicle-stimulating hormone, 167–168
FSH/LH challenge tests, 168–169
growth hormone, 161–162
growth hormone stimulation tests, 162–163
growth hormone suppression tests, 163
luteinizing hormone, 169–170
prolactin, 163–164
thyroid-stimulating hormone, 165–166
TSH stimulation test, 166–167
pancreatic, 187–190
C-peptide, 189
glucagon, 189–190
insulin, 188–189
parathyroid, 176–177
placental, 185–187
human chorionic gonadotropin, 185–186
human placental lactogen, 186–187
thyroid, 171–176
calcitonin, 176
thyroxine, 172–173
thyroxine-binding globulin, 175–176
triiodothyronine, 173–174
triiodothyronine uptake, 174–175
Household toxins, toxic doses and effects, 218–219t

Howell-Jolly bodies, causes of, 26t
hPL. See Human placental lactogen
hPRL. See Prolactin
Human chorionic gonadotropin (hCG), 185–186
as tumor marker, clinical associations, 91
urinary, 255–256
indications for measuring, 260
reference values, 259t
Human immunodeficiency virus (HIV), tests for, 88–89
Human leukocyte antigen (HLA) test, 101–102
diseases associated with, 101t
Human placental lactogen (hPL), 186–187
-Hydroxybutyric dehydrogenase, 157
17-Hydroxycorticosteroids (17-OHCS), urinary, 252
indications for measuring, 259
5-Hydroxyindoleacetic acid
as tumor marker, clinical associations, 91
urinary, 255
indications for measuring, 260
reference values, 258t
Hydroxyproline, urine, 262
reference values, 263t
Hyperaldosteronism, 253
Hyperchromia, 24t
Hyperglycemia, causes of, 106t
Hypersplenism, 42
Hypertension, chronic, profile/panel groups, 648
Hyperthyroidism, 172
Cytomel/perclorate suppression studies in, 523–524
Hypoalbuminemia, causes of, 115t
Hypochromia, characteristics and significance of, 24t
Hypogammaglobulinemia, 68
Hypoglycemia, causes of, 106t
Hypophysis. See Pituitary glands, hormones of
Hypothyroidism, 172
TSH radionuclide study in, 523
Hypoxia
erythropoiesis and, 4–5
tissue, causes of, 5t
Hysterosalpingography, 433–434

I
IAT. See Indirect antiglobulin test
Immune complex assays, 73
Immune deficiency diseases
abnormal T-cell subsets in, 63t
blockage of lymphocyte maturation in, 66f
helper–suppressor cell imbalance in, 61t
Immune response, categories of, 60
Immune system, profile/panel groupings and tests, 647
Immunoblast transformation test, 66
reference values, 67t
Immunodiffusion, for fungal infections, 78t
Immunoglobulins
B-cell, as tumor marker, clinical associations, 91
IgA, causes of altered levels in, 65t
IgD, causes of altered levels in, 65t
IgE
causes of altered levels in, 66t
radioallergosorbent test for, 73–74
IgG
assays of, 68–71
causes of altered levels in, 65t
in cerebrospinal fluid, 277t
conditions causing excessive levels of, 69t

663

664

INDEX

Immunoglobulins (Continued)
reference values, 70
IgM, causes of altered levels in, 65t
Immunohematology, 96
Immunologic antibody tests, 77–78
Immunology, 60–95
Inclusions, in synovial fluid, 293t
Indirect antiglobulin test (IAT), 100–101
Indirect fluorescent antibody tests, for fungal and parasitic
infections, 78t
Indirect immunofluorescent test, 78t
Indium 111 (111In), 484t, 489, 492
Industrial toxins, toxic doses and effects, 218–219t
Infections and infectious diseases
bacterial, antibody tests for, 80–82
isolation procedures, CDC guidelines for, 634–635
nursing goals and interventions, 649
profile/panel groupings and tests, 647
skins tests for, 619
blastomycosis, 622–623
coccidioidomycosis, 622, 623
histoplasmosis, 622, 623
mumps, 621–622
toxoplasmosis, 623, 624
trichinosis, 623–624
tuberculin, 620–621
Infectious mononucleosis tests, 85–87
Inflammatory bowel disease, GI bleeding in, 326t
Informed consent, for nuclear studies, 483
INR. See International Normalized Ratio
Insulin, 187
antibodies to, reference values, 76t
metabolic effects, 105t
tests for, 188–189
International Normalized Ratio (INR), 49
International Sensitivity Index, 49
International Units, for enzyme activity, 140
Intestinal biopsy, 345–347
Intestinal hormones, 190–191
Intradermal tests, 617–618. See also Skin tests
Intravenous cholangiography (IVC), 419
nursing alert, 419
Intravenous pyelogram (IVP), 424, 429–430
Inulin, clearance test, 239
Iodinated contrast media
adverse reactions to, 399t
in angiography, 438
Iodine
physiological function of, 212
as radionuclide, 485
Iron studies, 11
indications for, 11–12
procedure and nursing care for, 12–13
reference values, 12t
Isocitrate dehydrogenase, 146
Isolation procedures, CDC guidelines for, 634–635
IVC. See Intravenous cholangiography
IVP. See Intravenous pyelogram
Ivy method, of bleeding time, 44, 45
procedure, 45–46

J
Jaeger test, 605, 606
Jaundice, urine urobilinogen and bilirubin in, 229t
Joints
arthrography of, 431–432

radionuclide-mediated studies scanning studies of,
490–492

K
Karyotyping, of fetal cells, 298
17-Ketogenic steroids, urinary, 254
indications for measuring, 259–260
reference values, 257t
Ketonuria, 224, 226, 228
17-Ketosteroids, urinary, 253–254
indications for measuring, 259
reference values, 257t
Kidney(s)
angiography of, 449–450
biopsy of, 339–341
indications for, 340
nursing alert, 340
procedure and nursing care for, 340–341
disease, laboratory correlations in, 235–236t
function tests, 239–244
radionuclide-mediated scanning studies of, 510–512
tubular function tests, 240–241
ultrasonography of, 470–471
Krebs cycle, isocitrate dehydrogenase in, 146
Krypton 81m, 485t

L
Lactate dehydrogenase (LD), as tumor marker, clinical
associations, 91
Lactic acid, in cerebrospinal fluid, 276
Lactic dehydrogenase, 155–156
in plural fluid, 287t
Landau micro method, for ESR determination, 32t
LAP. See Leukocyte alkaline phosphatase
Laparoscopy, 389–394
gastrointestinal
indications for, 390–391
procedure for, 392
reference values, 390
gynecological, 389
indications for, 391
procedure for, 392–393
reference values, 390
indications for, 390–391
nursing care for, 391–392, 393–394
Laryngoscopy
direct, 365–366
indications for, 365
indirect, 364, 365f
nursing alert, 365
procedure and nursing care for, 365–367
Latex agglutination, for fungal and parasitic infections, 78t
LDL. See Low-density lipoproteins
Lecithin-to-sphingomyelin ratio, 132, 300–301, 301
reference values, 302t
Lee-White coagulation time, 52–53
reference values, 53t
Leptocytosis, characteristics and significance of, 25t
Leucine aminopeptidase
serum, 144–145
urinary, 250, 251
indications for testing, 251
testing procedure, 252
Leukoagglutinins, 97

INDEX

Leukocyte alkaline phosphatase (LAP), 37–38
Leukocyte esterase, in urine, 230
Leukocyte studies, 32–38
differential white blood cell count, 34–36
reference values, 35t
white blood cell count, 33–34
reference values, 33t
white blood cell enzymes
leukocyte alkaline phosphatase, 37–38
periodic acid–Schiff stain, 38
reference values, 38t
Leukocyte(s), 3
in duodenal secretions, 317
in feces, 322
in gastric secretions, 313
in pericardial fluid, 285t
reference values, 15t
differential count, 16t
in urine, 231
Leukocytosis, causes of, 6t
Leukopenia, causes of, 6t
Leukopoiesis, 6–7
altered, causes of, 6t
LH. See Luteinizing hormone
LHRH. See Gonadotropin-releasing hormone
Limulus assay, of cerebrospinal fluid, 280
Lipase, serum, 148–149
Lipids, cardiac, profile/panel groupings, 644
Lipoproteins
classification of, 127
composition of, 127t
fractionation, 133–135
conditions associated with alterations in, 134t
phenotypes
clinical significance of, 136t
reference values, 137t
phenotyping, 135–137
reference values, 133t
Liver. See also Hepatobiliary system
angiography of, 447–449
biopsy of, 342–344
indications for, 342–343
nursing alert, 343
procedure and nursing care for, 343–344
radionuclide-mediated scanning studies of, 507–508
ultrasonography of, 469–470
Low-density lipoproteins (LDL), 133
conditions associated with altered levels of, 134t
reference values, 133t
Lower gastrointestinal series (LGI). See Barium enema
L:S ratio. See Lecithin-to-sphingomyelin ratio
LTH. See Prolactin
Lumbar puncture, 278–279
in CSF flow scan, 490
in thoracic CT, 534
Lung(s). See also Chest and thoracic studies
angiography of, 446–447
biopsy of, 347–348
nursing alert, 347
positron emission tomography of, 515–516
radionuclide-mediated scanning studies, 498–500
Lupus erythematosus cell preparation, 76t
reference values, 76t
Luteinizing hormone (LH), 169–170
challenge tests, 168–169
reference values, 170t
Luteinizing hormone-releasing hormone (LHRH). See
Gonadotropin-releasing hormone

665

Lymph node(s)
biopsy of, 344–345
ultrasonography of, 466
Lymphangiography, 451–453
Lymphocyte(s)
bone marrow
causes of altered levels of, 7t
reference values, 8t
causes of altered levels of, 36t
functions of, 33
tests for, 61–62
maturation, immunodeficiency diseases blocking, 66f
reference values, 16t
in synovial fluid, 293t
Lysozyme, urinary, 250, 251
indications for testing, 251
testing procedure, 252

M
Macrocytosis, characteristics and significance of, 24t
Macrophages. See Monocytes
Magnesium (Mg)
serum, 204–206
disorders and drugs associated with altered levels of,
205t
reference values, 205t
urinary, 245–246
Magnetic resonance imaging (MRI), 529, 537
abdominal, 540–541
angiography, 539–540
body, 537–539
head and intracranial, 541
heart and chest, 541–542
musculoskeletal, 542–544
Magnevist, 537
Mallory-Weiss tears, at gastroesophageal junction, GI
bleeding in, 326t
Mammography, 411–412
American Cancer Society recommendations on, 411
Mammotest, 336
Manganese, blood levels, 212
Manometric studies, 545–557
esophageal, 550–552
fetoplacental adequacy, 555–557
oculoplethysmography, 554–555
plethysmography, 552
arterial, 552–553
body, 553–554
venous, 553
urodynamic, 545–546
cystometry, 546–548
urethral pressure profile, 549–550
uroflowmetry, 548–549
Mantoux test, 618, 620
reference values, 619
Masking level differences, 603t, 604
MCH. See Mean corpuscular hemoglobin
MCHC. See Mean corpuscular hemoglobin concentration
MCV. See Mean corpuscular volume
M:E ration. See Myeloid-to-erythroid ratio
Mean corpuscular hemoglobin concentration (MCHC), 22
reference values, 15t, 23t
Mean corpuscular hemoglobin (MCH), 22
reference values, 15t, 23t
Mean corpuscular volume (MCV), 22
reference values, 15t, 23t

666

INDEX

Measurement, units of, 636–643
Meat fibers, fecal examination for, 323
Meckel’s diverticulum
GI bleeding in, 326t
nuclear scanning, 505–506
Mediastinoscopy, 371–372
nursing alert, 371
Megakaryocytes, bone marrow, reference values, 8t
Meningitis, acute bacterial, 280
Mesenteric angiography, 450–451
Methemoglobinemia, 27
Metyrapone, 178
Microbiologic studies. See also Culture and sensitivity tests;
Culture(s)
of feces, 329–331
indications for, 331
of urine, 264–265
Microcytosis, characteristics and significance of, 24t
Minerals
trace, blood levels, 212–213
in urine, 264
Mixed lymphocyte culture (MLC), 67
MLC. See Mixed lymphocyte culture
Molybdenum, physiological function of, 212
Monoclonal gammopathies, 68, 69t
Monocytes
causes of altered levels of, 36t
function of, 32
reference values, 16t
in synovial fluid, 293t
Monosodium urate (MSU) crystals, in synovial fluid, 292,
293t
Mosenthal test, 242, 243–244
MRI. See Magnetic resonance imaging
Mucus, in gastric secretions, 313
MUGA. See Multiple gated acquisition imaging
Multiple gated acquisition imaging (MUGA), 495, 497
Mumps, skin test for, 621–622
Muramidase. See Lysozyme, urinary
Musculoskeletal system
magnetic resonance imaging of, 542–544
profile/panel groupings and tests, 646
Myasthenia gravis, Tensilon test in, 595
Mycobacterium tuberculosis
acid-fast smear and culture of, 272
in gastric secretions, 313
Mycoplasma pneumoniae infection, 82
Myeloblasts, bone marrow, reference values, 8t
Myelography, 434–436
Myeloid-to-erythroid (M:E) ratio, 7
reference values, 7
Myocardial imaging, 497
Myocardial infarction. See Acute myocardial infarction
Myoglobin
in acute myocardial infarction, 152
as cardiac marker, 153t

N
Narcotics, toxic blood levels, 216t
Neck, computed tomography scanning of, 533–534
Neisseria meningitidis, in cerebrospinal fluid, 280
Nephrotomography, 429
Neural tube defects, amniotic fluid analysis for, 298–299
Neurogenic bladder, types and effects of, 546t
Neurological system

profile/panel groupings and tests, 645
studies of, 594
acoustic admittance tests, 599–601
color perception tests, 608–609
corneal staining test, 613–614
hearing loss audiometry, 596–598
hearing loss tuning fork tests, 598–599
otoneural lesion site tests, 603–604
otoneurological tests, 601–603
refraction, 610–611
Schirmer tearing test, 612–613
slit-lamp biomicroscopy, 611–612
spinal nerve root thermography, 594–595
spondee speech reception threshold test, 604–605
Tensilon test, 595–596
tonometry, 609–610
visual acuity tests, 605–607
visual field tests, 607–608
Neurosyphilis, CSF serologic test for, 281
Neutrophils
bone marrow
causes of altered levels of, 7t
reference values, 8t
causes of altered levels of, 34t
in CBC, reference values, 16t
function of, 32
in synovial fluid, 293t
Newborn(s)
arterial blood gas values in, 208t
blood collection in, 629
for VDRL/RPR tests, 84
hemolytic disease of, tests for, 299
Nonesterfied fatty acids (NEFAs), 127
Nonimmune transformation tests, reference values, 67t
Norepinephrine
in aldosterone challenge tests, reference values, 181t
in urine, reference values, 257t
Normoblasts, bone marrow
causes of altered levels of, 7t
reference values, 8t
Nose, culture and sensitivity testing, 355–356
Nuclear scanning, 482–527
positron emission tomography, 485–486, 514–516
radionuclide laboratory studies, 486–487
radionuclide-mediated studies, 487
adrenal scanning, 493–494
bone and joint scanning, 490–492
bone marrow scanning, 492–493
brain scanning, 487–489
cardiac scanning, 495–498
cerebrospinal fluid flow scanning, 489–490
deep vein scanning, 508–509
gallbladder/biliary system scanning, 509–510
Gallium 67 scanning, 513–514
gastric emptying scanning, 502–503
gastrointestinal bleeding scanning, 504–505
gastrointestinal reflux scanning, 503–504
kidney/renography scanning, 510–512
liver scanning, 507–508
lung scanning, 498–500
Meckel’s diverticulum scanning, 505–506
pancreas scanning, 506–507
parathyroid scanning, 501
parotid/salivary gland scanning, 490
pheochromocytoma scanning, 494–495
scrotal scanning, 512–513
spleen scanning, 508

INDEX

thyroid scanning, 500–501
radionuclides/radiopharmaceuticals used in, 484–485t
risks of, 487
single-photon emission computed tomography, 486
5′-Nucleotidase, 144
Null cells, 61
reference values, 64t
Nursing care plan, 649–650

O
O2 saturation, definition of, 207
Obstetric ultrasonography, 475–476
Occult blood, 325, 327
OCG. See Cholecystography, oral
Oculoplethysmography, 554–555
Oikilocytosis, 24
Olychromatophilia, 24t
Operative cholangiography, 422
Opsonization, 71
Oral cholecystography, 417–419
Orinase. See Tolbutamide tolerance test
Ornithine carbamoyltransferase, 146–147
Osmolality
of serum, 206–207
of urine, 242
Otoneural lesion site tests, 603–604
Otoneurological tests, 601–603
Oxalate
as anticoagulant, 40
urinary, 264
reference values, 264t
Oximetry, 591–592
Oxytocin challenge test, 556

P
Pain, nursing goals and interventions, 649
Pancreas
hormones of, 187–190
radionuclide-mediated scanning studies of, 506–507
retrograde cholangiopancreatography, 377–379
tests and procedures, profile/panel groups, 646
ultrasonography of, 468–469
Papanicolaou (Pap) smear, 332–334
procedure and nursing care for, 334–335
Para-aminohippuric acid (PAH), clearance test, 239
Paracentesis, 291
Paranasal sinuses, tomography of, 411
Parasites
antibody tests for, 78t
in duodenal secretions, 317
fecal, tests for, 323–324
Parathyroid glands
hormones, 176–177
radionuclide-mediated scanning studies of, 500–501
tests and procedures, profile/panel groups, 646
ultrasonography of, 464–465
Parathyroid hormone (PTH), 176–177
Parotid gland, radionuclide-mediated scanning study of, 490
Partial thromboplastin time (PTT), 51
reference values, 52t
PAS stain. See Periodic acid–Schiff stain
Past-pointing test, 601–602
reference values, 602

667

Patch test, 617
Paul-Bunnell antibody, 86
pCO2, definition of, 207
PCR. See Polymerase chain reaction
PCT. See Prothrombin consumption time
Pelvic floor sphincter electromyography, 566–567
Pelvimetry, 405–406
Pelvis
computed tomography of, 536–537
pelvic floor sphincter electromyography, 566–567
ultrasonography of, 474–475
Pelviscopy. See Laparoscopy, gynecological
Peptic ulcer, GI bleeding in, 326t
Perchlorate suppression, 523–525
Percutaneous transhepatic cholangiography (PTHC),
422–424
needle placement in, 423t
nursing alert, 423
procedure, 424
Percutaneous transluminal coronary angioplasty (PTCA),
578
Percutaneous umbilical cord blood sampling (PUBS), 625
Perfusion scanning, 498–500
Pericardial fluid
analysis of, 284–286
reference values, 285t
Pericardiocentesis, 285–286
Perimetric test, 608
reference values, 608
Periodic acid–Schiff stain (PAS), 37t, 38
reference values, 38t
Peritoneal fluid
analysis of, 289–292
procedure and nursing care for, 291–292
reference values, 290t
Persantine, 495
PET. See Positron emission tomography
pH
in arterial blood gas, 208t
definition of, 207
of duodenal secretions, 317
effects of CO2 on, 208t
of gastric secretions, 313
of plural fluid, 287t
scale and selected values, 643
of semen, 309t
of sputum, 268
of urine, 224–225
Phenolsulfonphthalein (PSP) test, 240–241
nursing alert on, 241
Phenotyping, lipoproteins, 135–137
clinicopathological significance of, 136t
reference values, 137t
Phenylketonuria (PKU), 262
urine in, 224
Pheochromocytoma
radionuclide-mediated scanning studies of, 494–495
VMA testing and, 254
Phonocardiography, 563–564
Phosphate, serum, 202–204
disorders and drugs associated with altered levels of,
203t
reference values, 203t
Phosphatidylglycerol, amniotic fluid
reference values, 301
test for fetal maturity, 301
Phosphatidylinositol, amniotic fluid, reference values, 301

668

INDEX

Phospholipids, 125
reference values for, 132t
tests for, 131–133
Phosphorus
serum, 202–204
disorders and drugs associated with altered levels of,
203t
reference values, 203t
urinary, 245
Pilocarpine iontophoresis sweat test. See Sweat test
Pipyridamole, 497
Pituitary glands
hormones of, 160–171; See also Adrenocorticotropic
hormone; Follicle-stimulating hormone; Growth
hormone; Luteinizing hormone; Prolactin;
Thyroid-stimulating hormone
tests and procedures, profile/panel groups, 646
PK. See Pyruvate kinase
Placental hormones, 185–187
Plasma. See also Serum
composition of, 3
fibrinogen levels, 57–58
volume, radionucleide-mediated study, 517
Plasma cells
antibody production in, 62
bone marrow
causes of altered levels of, 7t
reference values, 8t
Platelet antibody tests, 97
Platelets
aggregation
drugs impairing, 46t
tests of, 46–47
causes of altered levels of, 43t
count, 42
critical values, 44
procedure and nursing care for, 44
reference values, 43
functions of, 39–40
causes of alterations in, 42t
reference values, in CBC, 16t
survival time, 521f
radionuclide-mediated laboratory studies of, 520–521
Plethysmography, 552
arterial, 552–553
in arterial Doppler extremity studies, 477
body, 553–554
in pulmonary function studies, 588
ocular, 552–553
venous, 553
Pleura, biopsy of, 348–349
nursing alert, 349
Pleural fluid
analysis of, 286
procedure and nursing care for, 288–289
profile/panel grouping, 645
indications for, 287–288
reference values, 287t
transudates vs. exudates, differentiation, 288t
Pluripotential stem cells, 4
Pneumonia, bacterial, 271
sputum characteristics in, 269
pO2, definition of, 207
Poikilocytosis, characteristics and significance of, 24t
Poisons. See Toxins
Polychromatophilia, characteristics and significance of, 24t
Polyclonal gammopathies, 68, 69t

Polymerase chain reaction (PCR), of sputum, 269
Porphobilinogen (PBG), urinary, 247
reference values, 249f
Porphyrins, 247
Portal venography, 447, 448
Porter-Silber chromogens, 253
Positron emission tomography (PET), 485–486, 514–516
cardiac nuclear scanning, 498
indications for, 515
procedure and nursing care for, 515–516
Postcoital test, in semen analysis, 309t
Postprandial test, of blood glucose levels, 108–109
Potassium (K)
serum, 192–196
disorders and drugs associated with altered levels of,
194–195t
nursing alert, 195
urinary, 245
PPD. See Tuberculin test
PR interval, 559, 559f
Prebycusis, 597
Pregnancy
hCG in detection of, 185–186
tests and procedures in, profile/panel groups, 647
ultrasonography in, 475–476
risks of, 460
Pregnanediol, urinary, 255
indications for measuring, 260
reference values, 259t
Pregnanetriol, urinary, 254
indications for measuring, 260
reference values, 257t
Presbyopia, 606
Pressure, conversion factors, 642
Proctosigmoidoscopy, 379–381
indications for, 379
nursing alert, 380
procedure and nursing care for, 380–381
Profile/panel groupings, 644–648
Progesterone, 183–184
in evaluation of amenorrhea, 168
Prolactin (hPRL, LTH), 163–164
reference values, 164t
Prostate
biopsy of, 349–350
ultrasonography of, 472
Prostate acid phosphatase (PAP), clinical associations, 91
Prostate-specific antigen (PSA), 150
clinical associations, 91
Protein(s)
in cerebrospinal fluid, 276
in plural fluid, 287t
serum, 114–118
protein metabolites, 120–125
reference values, 117t
urinary, 225, 261
indications for measuring, 262
reference values, 263t
Proteinuria, 225
Prothrombin, 50
Prothrombin consumption time (PCT), 54
Prothrombin time (PT, pro time)
critical values, 51
procedure and nursing care for, 51
reference values, 50t
Protonormoblasts, bone marrow, reference values, 8t
PSA. See Prostate-specific antigen

INDEX

Pseudocholinesterase (PCE), 157–158
PSP test. See Phenolsulfonphthalein test
Psychiatric drugs, toxic blood levels, 217t
PT. See Prothrombin time
Pteroylglutamic acid. See Folic acid
PTH. See Parathyroid hormone
PTHC. See Percutaneous transhepatic cholangiography
PTT. See Partial thromboplastin time
PUBS. See Percutaneous umbilical cord blood sampling
Pulmonary angiography, 446–447
Pulmonary artery catheterization, 582–583
nursing alert, 582
Pulmonary function studies, 586–590
exercise, 590–591
reference values, 588t
Pulmonary system. See Respiratory system
Purines, 261
Pyelography, antegrade, 424–426
nursing alert, 425
Pyruvate kinase (PK), deficiency of, 31

Q
QRS complex, 559, 559f
Queckenstedt’s test, 278–279

R
Radioactive iodine uptake (RAIU) study, 521–523
reference values, 522
Radioallergosorbent test (RAST), for IgE, 73–74
Radioimmunoassay studies, 487
for hepatitis virus, 87–88
for PTH, 177
for T3, 173
uptake, 174
for T4, 172
for TBG, 174
for TSH, 166
Radiologic studies, 397–436. See also Angiography
abdominal films, 404–405
antegrade pyelography, 424–426
arthrography, 431–432
barium enema, 416–417
barium swallow, 413–414
bronchography, 432–433
cardiac films, 409–410
chest films, 402–404
cineradiography, 398
contrast media, 399, 413
dual energy X-ray absorptiometry, 408–409
extremity films, 407–408
fluoroscopy, 398
hysterosalpingography, 433–434
intravenous pyelogram, 429–430
myelography, 434–436
obstruction series, 405
operative cholangiography, 422
oral cholecystography, 417–419
orbital films, 401–402
pelvimetry, 405–406
percutaneous transhepatic cholangiography, 422–424
plain films, 399–400
radiation exposure risks, 399
retrograde cystography, 427–428
retrograde ureteropyelography, 428–429

669

retrograde urethrography, 426–427
sialography, 430–431
skull films, 400–401
spinal films, 406–407
tomography, 398
chest, 410–411
paranasal sinus, 411
T-tube cholangiography, 420–422
upper gastrointestinal series, 414–416
voiding cystourethrography, 430
xeroradiography, 398–399
mammography, 411–412
Radionuclide-mediated laboratory studies, 516–527
platelet survival time, 520–521
radioactive iodine uptake, 521–523
red blood cell survival time, 517–520
Schilling test, 525–526
thyroid Cytomel/perchlorate suppression, 523–525
thyroid-stimulating hormone, 523
total blood volume, 516–517
Radionuclide-mediated scanning studies, 487
brain, 487–488
Radionuclides, 482, 483
diagnostic scanning uses, 484–485t
diagnostic uses, 484–485t
as interfering factor in hepatitis tests, 87–88
in PET, 514–515
in SPECT, 486
Radiopharmaceuticals, diagnostic uses, 484–485t
Raji cell assay, 73
Rapid plasma reagin (RPR) tests, 84–85
causes of false positive reactions to, 83t
RAST. See Radioallergosorbent test
Raynaud’s syndrome, 585
Red blood cell indices, 22–23
indications for, 24
reference values, 15t, 23t
Red blood cell survival time study
indications for, 518
procedure and nursing care for, 518–520
reference values, 518
Red blood cells (RBCs). See Erythrocyte(s)
Refraction, 610–611
Reiter cells, in synovial fluid, 293
Reiter complement fixation test, 281
Renal-urologic systems, profile/panel groupings and tests,
646
Renin, 158–160
testing
indications for, 159
nursing alert for, 159
procedure, 159–160
reference values, 158t
Renography, 510–511
nursing care and procedure, 512
Reproductive system, profile/panel groupings and tests,
646–647
Respiratory distress syndrome (RDS), of newborns, 300
Respiratory system. See also Chest and thoracic studies;
Lung(s)
profile/panel groupings and tests, 645
secretions of, 268
studies of, 586
exercise pulmonary function, 590–591
oximetry, 591–592
pulmonary function, 586–590
upper, culture and sensitivity testing, 355–356

670

INDEX

Rest cardiac scan, 497
Reticulocyte(s), 9
bone marrow, causes of alterations in, 7t, 8t
causes of altered levels of, 7t
peripheral blood, count, 9–11
indications for, 10
procedure and nursing care for, 10–11
reference values, 10t
reference values, 8t
Reticulocytosis, 10
Reticuloendothelial cells, 4
Retina, fluorescein angiography of, 451–452
Retrograde cholangiopancreatography
indications for, 377
procedure and nursing care for, 378–379
Retrograde cystography, 427–428
Retrograde ureteropyelography, 428–429
Retrograde urethrography, 426–427
Retroperitoneal ultrasonography, 466
Rh factor, in hemolytic disease of newborn, 299
Rheumatoid factor (RF), 75t
reference values, 76t
Rib cage, 407f
Rice bodies, in synovial fluid, 293
Rickettsial infections, febrile agglutinin tests for, 82t
Rinne test, 598, 599
reference values, 599
Romberg test, 601–602
reference values, 602
Rouleaux formation, 31
RPR. See Rapid plasma reagin tests
Rumple-Leeds capillary fragility test, 48–49
causes of positive results, 48t

S
Salivary glands, radionuclide-mediated scanning study of,
490
Salmonella infections, febrile agglutinin tests for, 82t
Scan studies, non-nuclear, 528–544. See also Nuclear
scanning
computed tomography, 528–529, 529–532
abdominal scanning, 535–536
body scanning, 530–531
head and intracranial scanning, 531–533
neck and spinal scanning, 533–534
pelvic scanning, 536–537
thoracic scanning, 534–535
magnetic resonance imaging, 529, 537
abdominal, 540–541
angiography, 539–540
body, 537–539
head and intracranial, 541
heart and chest, 541–542
musculoskeletal, 542–544
Schiller test, 337
Schilling test, 525–526
nursing alert, 526
Schiøtz tonometer, 609
Schirmer tearing test, 612–613
Schistocytosis, characteristics and significance of, 25t
Schistosoma haematobium, in urine, 232
Schwabach test, 598, 599
reference values, 599
Scientific notation, 636
Scratch test, 616–617

Scrotum
radionuclide-mediated scanning studies of, 512–513
ultrasonography of, 473
Secretin test, 319
Selium 75 (75Se), 506
Semen
analysis of, 305–310
for fertility, 306–308
procedure and nursing care for, 308–310
formation of, 305–306
gross characteristics of, 306
reference values, 309t
sample collection, 309–310
tests for presence of, 308–309
Septicemia
after endoscopic retrograde cholangiopancreatography,
379
after percutaneous transhepatic cholangiography, 424
blood culture in, 353
nursing alert, 354
Sequential multiple analyzer (SMA), 644
Serologic tests
for bacterial infections, 80t
for neurosyphilis, 281
for viral diseases, 86t
Serous fluid, 283
gross characteristics of, 284
Serum
ferritin levels, by age and sex, 11f
iron levels, 11
reference values, 12t
protein electrophoretic patterns, 69f
vitamin B12, reference values, 13t
Serum glutamic-oxaloacetic transaminase (SGOT). See
Aspartate aminotransferase
Serum glutamic-pyruvic transaminase (SGPT). See Alanine
aminotransferase
Serum osmolality, 206–207
SGOT. See Aspartate aminotransferase
SGPT. See Alanine aminotransferase
SH. See Growth hormone
Shake test, for fetal maturity, 301
reference values, 302t
SI (Système International) units, 636–638
Sialography, 430–431
Sickle cell thalassemia, 27
hemoglobin formation in, 28f
Sickledex text, 27
Siderotic granules, causes of, 26
Signal-averaged ECG, 565–566
Sims-Huhner test, 308
Single-photon emission computed tomography (SPECT), 486
in radionuclide-mediated scanning
of brain, 489
of liver, 508
Sinuses, paranasal, tomography of, 411
Skin
antibodies to, 77t
reference values, 76t
biopsy of, 335
culture and sensitivity testing, 357–358
Skin tests, 615–624
for allergens, 615–616
intradermal tests, 617–618
patch test, 617
scratch test, 616–617
for immune competence, 618–619

INDEX

for infectious diseases, 619–620
histoplasmosis/coccidioidomycosis/blastomycosis,
622–623
mumps, 621–622
trichinosis/toxoplasmosis, 623–624
tuberculin, 620–621
for T- and B-cell assays, 62
Skull, radiologic studies of, 400–401
Slit-lamp biomicroscopy, 611–612
Small intestine, biopsy of, 345–347
Smith micro method, for ESR determination, 32t
Smooth muscle, antibodies to, reference values, 76t
Snellen test, 605–606
Sodium (Na)
serum, 191–192
disorders and drugs associated with altered levels of,
193t
reference values, 192t
urinary, 244–245
Somatostatin, 187
metabolic effects, 105t
Specific gravity, of urine, 224
SPECT. See Single-photon emission computed tomography
Spectrophotometric analysis, of amniotic fluid, 300
Speech reception threshold test, 604–605
Sperm
morphology of, 307, 309t
abnormalities in, 307f
motility of, 309t
grades of, 307t
Spherocytosis, characteristics and significance of, 25t
Sphingomyelin. See Lecithin-to-sphingomyelin ratio
Spinal nerve root thermography, 594–595
Spine
cervical, 400f
computed tomography scanning of, 533–534
lumbar puncture, 278–279
radiologic studies of, 406–407
thoracic and lumbosacral, 407f
Spleen
radionuclide-mediated scanning studies of, 508
ultrasonography of, 468
nursing alert, 468
Spondee speech reception threshold test, 604–605
Sputum
analysis of, 268–273
acid-fast bacillus smear and culture, 272
culture and sensitivity, 271
cytologic examination, 271–273
profile/panel groupings, 645
stains, 269–271
production of, 268
Squamous cell carcinoma (SCC) antigen, clinical
associations, 91t
ST segment, 559, 559f
Staining
acid-fast, 272
bone marrow, 7–8
Gram
of cerebrospinal fluid, 280
of sputum, 269
of synovial fluid, 292
periodic acid–Schiff (PAS), 37t, 38
red blood cell, 24–26
Staphylococcal antibody tests, 80–81
Stem cell(s), in hematopoiesis, 4
STH. See Growth hormone

Stomatocytosis, characteristics and significance of, 25t
Stool cultures, 329–331
Streptococcal antibody tests, 81–82
Streptokinase-streptodornase test, 618
reference values, 619
Stress test. See Exercise ECG
Striated muscle
antibodies to
diseases associated with, 77t
reference values, 76t
biopsy of, 344
Sugars, nonglucose, in urine, 226
Sulfhemoglobin, 27
Sulkowitch’s test, 245, 247
Suppressor T cells, 61
balance with helper T cells, 61t
reference values, 64t
Suprapubic aspiration, for urinalysis, 332–333
Sweat test, 592–594
nursing alert, 593
Synovial fluid, 283
analysis of, 292–296
indications for, 294–295
reference values, 293
crystals in, 293t
gross characteristics of, 284
white blood cells and inclusions seen in, 293t
Syphilis tests, 83
fluorescent treponemal antibody, 80t, 281
fluorescent treponemal antibody-absorption, 80t,
83–84
rapid plasma reagin tests, 84–85
causes of false positive reactions to, 83t
venereal disease research laboratory, 80t, 84–85

T
T lymphocytes
abnormal subsets, causes of, 61, 63t
antigen response of, 67f
assays of, 62–64, 66
causes of altered levels of, 63t
function of, 33, 61, 62
reference values, 16t, 64t
Tangent screen test, 608
Tartrate-resistant acid phosphatase (TRAP), 38t, 39
Tay-Sachs disease
fetal cell karyotyping for, 298
hexosaminidase and, 156–157
TBG. See Thyroxine-binding globulin
TCT. See Thrombin clotting time
Technetium 99m (99mTc), 484t, 487
Temperature, conversion factors, 642
Template method, of bleeding time, 44
procedure, 45–46
Tensilon test, 595–596
Testosterone, 184–185
T4. See Thyroxine
-Thalassemia, 26–27
hemoglobin formation in, 28f
-Thalassemia, 26
hemoglobin formation in, 28f
Thalassemias, 26–27
Thallium 201, 485t
Thermography, spinal nerve root, 594–595
Thiamine. See Vitamin B1

671

672

INDEX

Thoracoscopy, 372–374
nursing alert, 373
Throat, culture and sensitivity testing, 355–356
Thrombin, 40
Thrombin clotting time (TCT), 40
Thrombocytes. See Platelets
Thrombocytopenia
causes of, 43t
nursing care after venipuncture in, 44
Thrombocytosis
causes of, 43t
nursing care after venipuncture in, 44
Thrombopathies, 42
Thrombosis, venous, after PT testing, nursing care, 51
Thyrocalcitonin. See Calcitonin
Thyroglobulin, antibodies to, reference values, 76t
Thyroid Cytomel/perchlorate suppression studies, 523–525
Thyroid glands
biopsy of, 350–351
hormones of, 171–176
radionuclide-mediated scanning studies of, 500–501
tests and procedures, profile/panel groups, 646
ultrasonography of, 464–465
Thyroid-stimulating hormone (TSH), 165–166
radionuclide-mediated laboratory studies, 523
reference values, 166t
stimulation test, 166–167
reference values, 167
Thyroid-stimulating immunoglobulins (TSI, TSIg), 175–176
Thyrotropin-releasing hormone (TRH), 160
Thyroxine (T4), 171–173
metabolic effects, 105t
reference values, 172t
Thyroxine-binding globulin (TBG), 175–176
TIBC. See Total iron-binding capacity
Time, conversion factors, 642
Titer, definition of, 78
Tolbutamide tolerance test, 113
nursing alert for, 113
Tomography, 398
chest, 410–411
paranasal sinus, 411
Tone decay test, 604
reference values, 603
Tonometry, 609–610
Total blood volume studies, 516–517
procedure and nursing care, 517
reference values, 516
Total complement (CH50), 71
reference values, 72t
Total iron-binding capacity (TIBC), 11
reference values, 12t
Tourniquet test, of capillary fragility, 48–49
Toxins, toxic doses and effects, 218–219t
Toxoplasmosis, skin test for, 623–624
Tracheal suctioning, for sputum specimen, 270
Transesophageal echocardiography, 463
Transferrin, 11
reference values, 12t
Transfusion reactions, nursing care for, 98
Transmission categories, for isolation precautions, 635
Trichinosis, skin test for, 623–624
Triglycerides
disorders and drugs associated with altered levels of, 125,
129t
in plural fluid, 287t
test for, 128–130

Triiodothyronine (T3), 171, 173–174
reference values, 174t
uptake test, 174–175
reference values, 174t
Troponin
serum levels, 154–155
type I, as cardiac marker, 154t
type T, as cardiac marker, 153t
Trypsin, in feces, 327
indications for testing, 329
reference values, 328t
TSH. See Thyroid-stimulating hormone
T3. See Triiodothyronine
T-tube cholangiography, 420–422
nursing alert, 421
tube placement in, 421f
Tuberculin test, 618, 620–621
procedure for, 621
Tularemia, febrile agglutinin tests for, 82t
Tumor markers, 646
classification of, 90
clinical associations, 91t
Tumors. See also Cancer(s)
profile/panel groupings and tests for, 647
Tuning fork tests, for hearing loss, 598–599
Typanometry, 599–600
reference values, 600
Tyrosyluria, 262

U
UA. See Urinalysis
UGI. See Upper gastrointestinal series
Ultrasound studies, 458–481
abdominal/aoric ultrasonography, 466–467
bladder ultrasonography, 471–472
breast ultrasonography, 473–474
devise to detect blood flow velocity, 460f
Doppler ultrasound technique, 459
arterial extremity studies, 477–478
arterial transcranial, 479–480
carotid artery, 478–479
procedures in, 476
venous extremity studies, 480–481
echocardiography, 460–462
transesophageal, 463
echoencephalography, 462–463
liver/biliary system ultrasonography, 469–470
lymph node/retroperitoneal ultrasonography, 466
obstetric ultrasonography, 475–476
ocular ultrasonography, 463–464
pancreatic ultrasonography, 468–469
pelvic ultrasonography, 474–475
prostate ultrasonography, 472
renal ultrasonography, 470–471
risks of, 459–460
scrotal ultrasonography, 473
spleen ultrasonography, 468
thoracic ultrasonography, 465–466
thyroid/parathyroid ultrasonography, 464–465
Upper gastrointestinal series (UGI), 414–416
procedure, 415
reference values, 414
Urea, clearance test, 239
Urea nitrogen
causes of altered levels of, 121t

INDEX

test for, 120–122
Ureteropyelography, retrograde, 428–429
Ureter(s), biopsy of, 338–339
Urethral pressure profile, 549–550
reference values, 549t
Urethrography, retrograde, 426–427
Uric acid
serum
causes of altered levels of, 126t
critical values, 125
reference values, 125t
test for, 124–125
urinary, 261
indications for measuring, 262
Urinalysis (UA)
nursing alert, 237
profile/panel groups, 646
reference values, 237
routine, 222–239
indications for, 234, 237
interfering factors, 232
procedure and nursing care for, 237–238
sample collection for, 238
Urinary sediment, 222
Urinary tract infections (UTIs)
nitrite analysis and, 225
urine pH and, 225
Urine
appearance, 222
bilirubin in, 228–230
in jaundice, 229t
blood in, 228
casts in, 231–232
types and significance of, 233t
clearance tests, 239–240
color, 222
factors affecting, 223t
concentration and dilution tests, 241–242
indications for, 242–243
procedure and nursing care for, 243–244
crystals in, 232
characteristics and significance of, 234t
cytologic examination of, 265
drug screening tests of, 265–266
enzymes in, 250–252
reference values, 251t
epithelial cells in, 231
formation of, 221
glucose in, 225–226
drugs and disorders causing, 227t
drugs producing false-positive results, 227t
hormones in, 252–261
ketones in, 226, 228
leukocyte esterase in, 230
macroscopic analysis, 222–225
microbiologic examination of, 264–265
microscopic analysis, 230–232
nitrite in, 230
odor, 224
pH, 224–225
pigments in, 247–248
reference values, 249t
proteins in, 225, 261
indications for measuring, 262
reference values, 263t
red blood cells, 230–231
specific gravity, 224, 242

673

specimen collection
catheterized specimen, 332
in children, 633
clean-catch specimen, 331–332
double-voided specimen, 631
first morning specimen, 631
pediatric, 333
random specimen, 250, 631
suprapubic aspiration, 332–333
by suprapubic aspiration, 632
twenty-four hour (timed) specimen, 332
urobilinogen in, 228–230
in jaundice, 229t
white blood cells in, 231
Urine hydroxyproline, 262
reference values, 263t
Urobilinogen
in feces, 328
indications for testing, 329
in urine, 228–230
Urodynamic studies, 545–546
Uroflowmetry, 548–549
Uroporphyrin, 247
reference values, 249f

V
Vaginal samples, for semen presence, 309
Vanillylmandelic acid (VMA), urinary, 254–255
indications for measuring, 260
reference values, 257t
Vascular activity, 39–59
Vasoactive intestinal peptide (VIP), as tumor marker, clinical
associations, 91
VDRL. See Venereal disease research laboratory
Veins
deep, radionuclide-mediated scanning studies of, 508–509
of hand and wrist, 454f
of leg and foot, 455f
Venereal disease research laboratory (VDRL), 80t, 83, 84–85
Venipuncture, 626–627
Venous Doppler extremity studies, 480–481
Venous plethysmography, 553
Venous thrombosis, after PT testing, nursing care, 51
Ventilation-perfusion scanning, 498–500
Ventricular puncture, 279
Very-low density lipoproteins (VLDL), 133
conditions associated with altered levels of, 134t
reference values, 133t
Viral infections
antibody tests for, 85
hepatitis, 87–88
HIV, 88–90
infectious mononucleosis, 85–87
serologic tests for, 86t
Visual acuity tests, 605–607
Visual field tests, 607–608
confrontation test, 608
perimetric test, 608
tangent screen test, 608
Vitamin A, blood levels, 210–211
reference values, 210t
Vitamin B1, urinary, reference values, 264t
Vitamin B12
deficiency, Schilling test in, 525–526
serum, reference values, 13t

674

INDEX

Vitamin B12 (Continued)
studies
indications for, 13
procedure and nursing care for, 13–14
Vitamin C
blood levels, 211
reference values, 211t
urinary, reference values, 264t
Vitamin D, blood levels, 211
reference values, 212
Vitamins, in urine, 263–264
VLDL. See Very-low density lipoproteins
VMA. See Vanillylmandelic acid
Voiding cystourethrography, 430
Volume, conversion factors, 641
von Willebrand’s disease, 44, 45
von Willebrand’s factor, 39

W
Wassermann test, 281
WBC count. See White blood cell count
Weber test, 599
reference values, 599
Weights and measures, 639–640
conversion rules and factors, 640–643
Weil-Felix (OX-19) test, 80t
Westergren method, for ESR determination, 32t
Western immunoblot (WIB) assay, 89
White blood cell count (WBC)
critical values, 34
differential, 34
causes of alterations in, 34–36t

reference values, 16t, 35t
reference values, 33t
in CBC, 15t
White blood cell (WBC) count, 33
White blood cells (WBCs). See Leukocyte(s); Lymphocyte(s);
specific types
Whole blood clotting time, 52–53
WIB. See Western immunoblot assay
Widal test, 80t
Wintrobe method, for ESR determination, 32t
Wound(s), culture and sensitivity testing, 356–357
Wright’s stain, of sputum, 269

X
Xenon 133, 485t
Xeroradiography, 398–399, 411–412
X-rays. See Radiologic studies

Y
Yeasts
in gastric secretions, 313
sputum cultures for, 271
in urine, 232
nitrite analysis and, 230

Z
Zinc, physiological function of, 212

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Nurse�s Manual Of Laboratory And Diagnostic S 4th Ed 2003

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