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Frontmatter Title

Laboratory and Diagnostic Tests

A M A N U A L O F

N I N T H E D I T I O N

Laboratory and Diagnostic Tests

A M A N U A L O F

N I N T H E D I T I O N

Frances Talaska Fischbach, RN, BSN, MSN

Associate Clinical Professor of Nursing

School of NursingUniversity of Wisconsin-MilwaukeeMilwaukee, WisconsinAssociate Professor of Nursing (Ret)

School of NursingUniversity of Wisconsin-MilwaukeeMilwaukee, Wisconsin

Marshall Barnett Dunning III, BS, MS, PhD

Professor of Medicine & PhysiologyDepartment of MedicineDivision of Pulmonary/Critical Care MedicineMedical College of WisconsinMilwaukee, Wisconsin

Acquisitions Editor: Patrick Barbera

Managing Editor: Roxanne Halpine Ward

Design Coordinator: Holly McLaughlin

Art Director, Illustration: Jennifer Clements

Production Project Manager: Cynthia Rudy

Manufacturing Coordinator: Karin Duffield

Prepress Vendor: Absolute Service, Inc

9th Edition

Copyright © 2015 Wolters Kluwer Health | Lippincott Williams & Wilkins

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Copyright © 2004, 2000 by

Lippincott Williams & Wilkins Copyright © 1996 by Lippincott-Raven Publishers Copyright © 1992,

1988, 1984, 1980 by J B Lippincott Company All rights reserved This book is protected by copyright

No part of this book may be reproduced or transmitted in any form or by any means, including as

pho-tocopies or scanned-in or other electronic copies, or utilized by any information storage and retrieval

system without written permission from the copyright owner, except for brief quotations embodied in

critical articles and reviews Materials appearing in this book prepared by individuals as part of their

official duties as U.S government employees are not covered by the above-mentioned copyright

To request permission, please contact Lippincott Williams & Wilkins at Two Commerce Square,

2001 Market Street, Philadelphia, PA 19103, via email at permissions@lww.com, or via our website

at lww.com (products and services)

9 8 7 6 5 4 3 2 1

Printed in China

Library of Congress Cataloging-in-Publication Data

ISBN: 978-1-4511-9089-2

Cataloging-in-Publication Data available on request from the publisher

Care has been taken to confirm the accuracy of the information presented and to describe generally

accepted practices However, the authors, editors, and publisher are not responsible for errors or

omis-sions or for any consequences from application of the information in this book and make no warranty,

expressed or implied, with respect to the currency, completeness, or accuracy of the contents of the

publication Application of this information in a particular situation remains the professional

responsi-bility of the practitioner; the clinical treatments described and recommended may not be considered

absolute and universal recommendations

The authors, editors, and publisher have exerted every effort to ensure that drug selection and dosage

set forth in this text are in accordance with the current recommendations and practice at the time of

publication However, in view of ongoing research, changes in government regulations, and the constant

flow of information relating to drug therapy and drug reactions, the reader is urged to check the package

insert for each drug for any change in indications and dosage and for added warnings and precautions

This is particularly important when the recommended agent is a new or infrequently employed drug

Some drugs and medical devices presented in this publication have Food and Drug Administration

(FDA) clearance for limited use in restricted research settings It is the responsibility of the health care

provider to ascertain the FDA status of each drug or device planned for use in his or her clinical practice

LWW.COM

To the memory of Marshall B Dunning III

Dear friend and coauthor 1947–2013

New York, New York

Patricia A Van Kampen

Student Nurse

Research Assistant

Wausau, Wisconsin

Patti Cobb, RD, CD

Chief Clinical Dietitian

Food and Nutrition Services

Froedtert Hospital

Milwaukee, Wisconsin

Carol Colasacco, CT(ASCP), CMIAC

Cytotechnologist, Department of Pathology

Fletcher Allen Health Care

Karen Kehl, PhD Associate Professor-Pathology Children’s Hospital of Wisconsin Milwaukee, Wisconsin

Stanley F Lo, PhD, DABCC, FACB Associate Professor, Pathology Associate Director, Clinical Laboratories Technical Director, Clinical Chemistry, Point

of Care, and Biochemical Genetics Directory, Reference Standards Laboratory Children’s Hospital of Wisconsin

Medical College of Wisconsin Milwaukee, Wisconsin Charles R Myers, PhD Professor of Pharmacology and Toxicology Medical College of Wisconsin

Milwaukee, Wisconsin Christine Naczek, MT(ASCP) Manager, Blood Banking and Pre-Transfusion Testing

Department of Pathology United Regional Medical Services, Inc

Milwaukee, Wisconsin Anne Witkowiak Nezworski, RN, BSN Maternity and Newborn Specialist Marshfield Clinic, Eau Claire Center Eau Claire, Wisconsin

Contributors, Consultants, and Research Assistants

Contributors, Consultants, and Research Assistants Joseph Nezworski, ES, RN, BSN

Chief Deputy Medical Examiner

Eau Claire County

Nursing Supervisor

Sacred Heart Hospital

Eau Claire, Wisconsin

Medical College of Wisconsin

St Luke’s Medical Center

John Shalkham, MA, SCT(ASCP)

Program Director for School of Cytotechnology

State Laboratory of Hygiene

Clinical Assistant Professor

West Allis, Wisconsin

Thudung Tieu, MT(ASCP)

Quality Assurance & Safety Manager

Dynacare Laboratories

Milwaukee, Wisconsin

Jean M Trione, RPh Clinical Specialist Wausau Hospital Wausau, Wisconsin Patti Wilson BSN, RN, CIC Infection Control Coordinator Froedtert Hospital

Milwaukee, Wisconsin Michael Zacharisen, MD Professor of Pediatrics Children’s Hospital of Wisconsin Milwaukee, Wisconsin

Rush University College of Nursing Chicago, Illinois

Susan K Callen, MSN, RN, CNE Nursing Instructor II

UPMC Shadyside School of Nursing Pittsburgh, Pennsylvania

Sandi Casey MS, RNC-MNN Nursing Instructor

Connors State College Muskogee, Oklahoma Karen Chandra, MSN, MBA, RN Associate Professor of Nursing Harper College

Palatine, Illinois

viii Reviewers

Christine M Cunningham, MS, MT

(ASCP)

Associate Professor

New York Chiropractic College

Seneca Falls, New York

Pasquale Fiore, RN, BScN, MSc, Health

Nursing & Allied Sciences

Bronx Community College - CUNY

Bronx, New York

Cathy R Kessenich, DSN, ARNP, FAANP

Columbia-Greene Community College

Hudson, New York

Catherine Mbewe, MS, RN

Assistant Professor

Nursing and Allied Health Sciences

Bronx Community College - CUNY

Bronx, New York

Janet O’Connell, MA Ed, BN

Professor of Nursing

Ryerson University, Centennial College,

George Brown College Collaborative BScN

Program

Toronto, Ontario, Canada

Nancy E Pea, MSN, RN Associate Professor

St Louis Community College Ferguson, Missouri

Carswella Phillips, DNP, MSN, ARNP Assistant Professor

Florida Agricultural and Mechanical University, School of Nursing

Tallahassee, Florida Vanessa Pomarico-Denino, MSN, APRN, FNP-BC

Interim Director and Lead Faculty Family Nurse Practitioner Track

Southern Connecticut State University New Haven, Connecticut

Charlene Strumpel, MSN, RN Instructor

University of British Columbia, Okanagan Campus

Kelowna, British Columbia, Canada Angela Trott, MSN-Ed, BSN, RN Associate Degree Nursing Instructor Coastal Carolina Community College Jacksonville, North Carolina

S Wendy Whillans, MScN, RN Faculty, School of Nursing Canadore College North Bay, Ontario, Canada Mary Ellen Wilkosz, PhD, MSN, BSN, RN, FNP-BC

Associate Professor and Assistant Director FNP Program

Sonoma State University Rohnert Park, California

The purpose of A Manual of Laboratory and Diagnostic Tests, in this ninth edition, is to promote the

delivery of safe, effective, and informed care for patients undergoing diagnostic tests and procedures and also to provide clinicians and students, educators and researchers, and others with a unique resource This comprehensive manual provides a foundation for understanding diagnostic tests, from the relatively simple to the most complex, that are delivered to varied populations in varied settings

It describes in depth the clinician’s role in providing effective diagnostic services by providing the information necessary for quality care planning, individualized patient assessment, analysis of patient needs, appropriate interventions, patient education, patient follow-up, and timely outcome evaluation Potential risks and complications of diagnostic testing mandate that proper test protocols, inter-fering factors, follow-up testing, and collaboration among those involved in the testing process be a significant part of the information included in this text

ORGANIZATION

This book is organized into 16 chapters and 5 appendices Chapter 1 outlines the clinician’s role in diagnostic testing and includes interventions for safe, effective, informed pre-, intra-, and post-test care This chapter includes a Patient’s Bill of Rights and Responsibilities, a model for the role of the clinical team in providing diagnostic care and services, descriptions of different test environments, and discussion of reimbursement for diagnostic services, and emphasizes the importance of communication

as key to desired outcomes The intratest section includes information about collaborative approaches facilitating family presence during invasive procedures; risk management; the collection, handling, and transport of specimens; infection control; controlling pain; comfort measures; administration of drugs and solutions; monitoring fluid intake and loss; using required equipment kits and supplies; properly positioning the patient for the procedure; managing the environment; and patient monitoring The reader is referred back to Chapter 1, Diagnostic Testing, throughout the text for information about the clinician’s role and diagnostic services Chapters 2 through 16 focus on specific categories of studies

CHAPTER CONTENT AND FEATURES

Studies are organized in a similar way for ease of use and include:

x Preface

Reference Values

• Normal reference values

• Conventional and SI units

• Age-related values and critical values when applicable

Procedures

• Process of intratest care

• Method of specimen collection and handling for lab tests

• Method of diagnostic procedures

• Pre- and post-test patient care

• Specific guidelines for each test phase

Special Clinical Alerts , Procedural Alerts , and Notes N OT E appear frequently

throughout to signal special cautions

A fully updated bibliography at the end of each chapter, representing a composite of selected

refer-ences from various disciplines, directs the clinician to information available beyond the scope of this

book, and extensive appendices provide additional data for everyday practice

REVISIONS AND ADDITIONS TO THE NINTH EDITION

The newest concepts and technologies are included in this edition:

• Effects of drugs on lab outcomes

• Guidelines for Pap screening

• Guidelines for cancer screening

• Bioterrorism agent testing

• Pulmonary function testing

• Mother-baby screening

All chapters have been reviewed by experts in the field Current technologies have been

incorpo-rated throughout the text, maintaining emphasis on clinical and procedural alerts

CURRENT DEVELOPMENTS IN LABORATORY AND DIAGNOSTIC

TESTING

New technologies foster new scientific modalities for patient assessment and clinical interventions Thus,

the clinician is provided a greater understanding of the long chain of events from diagnosis through

treat-ment and outcomes In a brief span of years, new and improved technologies have led to developtreat-ments

in x-ray scanners, digital and enhanced imaging, magnetic resonance (MR), positron emission

tomogra-phy (PET) scans of the heart and brain, enhanced ultrasound and nuclear medicine procedures, newly

Prefacediscovered genetic mutation studies, new cancer markers for diagnosis and prognosis, technology for fetal testing before birth, and postmortem testing after death Many new technologies are faster, more patient friendly, more comfortable, and provide an equivalent or higher degree of accuracy (i.e., HIV or hepatitis detection, monitoring for drug abuse or managing therapeutic drug levels) Saliva and breath testing is gaining ground as a mirror of body function; DNA; and emotional, hormonal, immune, and neurologic status, as well as providing clues about faulty metabolism Noninvasive and minimally invasive testing (e.g., using a swab to collect saliva from the mouth, procedures that require only one drop of blood), which is better suited for testing in environments such as the workplace, private home, and other non-traditional health care settings such as churches, is made possible by better collection methods and stan-dardized collection techniques The newest diagnostic lab technologies include hand-held nucleic acid detectors for specific bacteria and viruses, handheld miniaturized chip-based DNA analyzers, reagent-less diagnostics that introduce the sample (hand, finger, ear lobe, etc.) to magnetic fields, and magnetic resonance spectroscopy (MRS) Noninvasive and minimally invasive diagnostics include infrared light

to estimate glucose, rapid oral screen for HIV, proteinomics, and functional and molecular techniques

A resurgence in the use of traditional, trusted diagnostic modalities, such as electroencephalogram (EEG), is being seen in certain areas Diseases such as HIV, antibiotic-resistant strains of pathologic organisms (TB), and type 2 diabetes are becoming more prevalent In the workplace, thorough diagnostic testing is more common as applications are made for employment and disability benefits Also, require-ments for periodic monitoring of exposures to potentially hazardous workplace substances (chemicals, heavy metals), breathing and hearing tests, and TB and latex allergy testing require skill in administering and procuring specimens The number of forensic identity DNA tests being performed has increased tre-mendously Concurrently, consumer perceptions have shifted from implicit faith in the health care system

to concerns regarding less control over choices for health care and more distrust of the system in general Managed care and its drive for control of costs for diagnostic services exert a tremendous effect on consumers’ ability to access testing services care This results in mixed access to services, depending

on approval or denial of coverage

These trends—combined with a shift in diagnostic care from acute care hospital settings to tient departments, physicians’ offices, clinics, community-based centers, nursing homes, and sometimes even churches, stores, and pharmacies—challenge clinicians to provide standards-based, safe, effective, and informed care Because the health care system is becoming a community-based model, the clini-cian’s role is also changing Updated knowledge and skills, flexibility, and a heightened awareness of the testing environment (point of care testing) are needed to provide diagnostic services in these settings Clinicians must also adapt their practice to changes in other areas This includes developing, coordi-nating, and following policies and standards set forth by institutions, governmental bodies, and regulatory agencies Being informed regarding ethical and legal implications such as informed consent, privacy, patient safety, the right to refuse tests, the right to truthful diagnoses and prognoses, end-of-life decisions, standards for quarantine to control infection, and trends in diagnostic research procedures adds another dimension to the clinician’s accountability and responsibility The consequences of certain types of testing (i.e., HIV and genetic) and the implications of confidential versus anonymous testing must also be kept

outpa-in moutpa-ind For example, anonymous tests do not require the outpa-individual to give his or her name, whereas confidential tests do require a name This difference has implications in the requirements and process of agency reporting for all patients as well as for select groups of infectious disease incidence such as HIV

Responding to these trends, the ninth edition of A Manual of Laboratory and Diagnostic Tests is

a comprehensive, up-to-date diagnostic reference source that includes information about newer nologies together with the time-honored, classic tests that continue to be an important component of diagnostic work It meets the needs of clinicians, educators, researchers, students, and others whose work and study requires this type of resource or reference manual

Frances Talaska Fischbach Marshall B Dunning III

I acknowledge with sincere gratitude the contributions made by all of those individuals who

partici-pated in the extensive revisions for the ninth edition of this book Special recognition is due to Marshall

B Dunning III for all work in relation to this text, especially this ninth edition

My thanks go to Mary Fischbach Johnson, Margaret Fischbach and Patricia Van Kampen for

their research and administrative support I especially thank the newest contributors, consultants, and

research assistants for their diligence and hard work to ensure the quality, completeness, and most

up-to-date information contained herein I would also like to acknowledge the valuable assistance of the

Lippincott Williams & Wilkins reviewers

My gratitude is extended to the entire staff at Lippincott Williams & Wilkins, especially Roxanne

Halpine Ward and Patrick Barbera Special recognition is also due to the editors and staff who have

worked on all prior editions of this work

Finally, I thank those special people, too numerous to mention, on whom we relied for support,

dedication, encouragement, and patience

Thank you all for a job well done!

Frances Talaska Fischbach

Acknowledgments

15 Prenatal Diagnosis and Tests of Fetal Well-Being / 984

16 Special Diagnostic, Special Specimen Collection, and

Postmortem Studies / 1033

APPENDICES

A Standard Precautions for Prevention and Control of Infection / 1122

B Guidelines for Specimen Transport and Storage / 1133

C Vitamins in Human Nutrition / 1141

D Minerals in Human Nutrition / 1155

E Effects of Drugs on Laboratory Tests (Blood, “Whole” Plasma, Serum,

Stool, and Urine) / 1176 Index / 1215

1 Diagnostic Testing

Overview of the Clinician’s Role: Responsibilities,

Standards, and Requisite Knowledge / 2

Pretest Phase: Elements of Safe, Effective,

Informed Care / 10

•Basic Knowledge and Necessary Skills / 10

•Testing Environments / 12

•History and Assessment / 13

•Reimbursement for Diagnostic Services / 13

•Ethics and the Law / 18

•Patient’s Bill of Rights and Patient Responsibilities / 22

•Cultural Sensitivity / 23 Intratest Phase: Elements of Safe, Effective,

•Specimens and Procedures / 25

•Equipment and Supplies / 28

•Family Presence / 29

•Positioning for Procedures / 29

•Administration of Drugs and Solutions / 29

•Management of Environment / 29

•Latex Sensitivity and Allergy / 30

•Pain Control, Comfort Measures, and Patient Monitoring / 34

•Sedation and Analgesia / 34 Posttest Phase: Elements of Safe, Effective, Informed Care / 39

•Basic Knowledge and Necessary Skills / 39

•Abnormal Test Results / 39

•Guidelines for Disclosure / 44

•Patient Responses to Diagnosis / 44

•Expected and Unexpected Outcomes / 45

Recovered Medical Errors / 48 Laboratory Response Network / 48 Biosafety / 48

Importance of Communication / 48 Conclusion / 50

2 C H A P T E R 1 ● Overview of the Clinician’s Role

OVERVIEW OF THE CLINICIAN’S ROLE: RESPONSIBILITIES,

STANDARDS, AND REQUISITE KNOWLEDGE

In this era of high technology, health care delivery involves many different disciplines and specialties

Consequently, clinicians must have an understanding and working knowledge of modalities other than

their own area of expertise This includes diagnostic evaluation and diagnostic services Laboratory and

diagnostic tests are tools to gain additional information about the patient By themselves, these tests

are not therapeutic; however, when used in conjunction with a thorough history and physical

exami-nation, these tests may confirm a diagnosis or provide valuable information about a patient’s status

and response to therapy that may not be apparent from the history and physical examination alone

Generally, an evidenced-based tiered approach to selecting tests is used:

1 Basic screening (frequently used with wellness groups and case finding)

2 Establishing (initial) diagnoses

3 Differential diagnosis

4 Evaluating current medical case management and outcomes

5 Evaluating disease severity

6 Monitoring course of illness and response to treatment

7 Group and panel testing

8 Regularly scheduled screening tests as part of ongoing care

9 Testing related to specific events, certain signs and symptoms, or other exceptional situations (e.g.,

infection and inflammation [bladder infection or cellulitis], sexual assault, drug screening,

pheo-chromocytoma, postmortem tests, to name a few) (Table 1.1)

Test selections are based on subjective clinical judgment, national recommendations, and

evidence-based health care Often, diagnostic tests or procedures are used as predictors of surgical risk

or morbidity and mortality rates because, in some cases, the risk may outweigh the benefit

Although more than 78 million adults use the Internet for health information, it is

impor-tant that they understand that not all information on the Internet is reliable Therefore, there is a

need to educate the patient about laboratory tests and diagnostic procedures

Recent national surveys have revealed that most individuals are not knowledgeable about

recom-mendations for primary screening tests used to detect various types of cancers Many times, patients

pressure their physicians to order various test procedures as well as treatment Patients sometimes

feel that more is better in terms of laboratory tests The potential for the clinician to order

unwar-ranted tests, or “blanket testing,” has resulted in significant cost to the health care system Multiplex

testing—conducting multiple tests on a single sample—however, can be beneficial under the right

cir-cumstances, such as with autoimmune disorders or genetically inherited diseases, and in the long run

can be cost saving Use of evidence-based guidelines for scheduling, selecting, retaining, or

eliminat-ing certain diagnostic tests may help achieve more effective case management and cost containment

These guidelines use a system that grades the quality of scientific evidence based on published reports

of clinical trials, expert consensus, or clinical expertise Levels of evidence are A to C and E, with A

being the best evidence and E referring to expert opinion or consensus (Chart 1.1)

As an integral part of their practice, clinicians have long supported patients and their significant

others in meeting the demands and challenges incumbent in the simplest to the most complex

diagnos-tic testing This testing begins before birth and frequently continues after death Prenatal testing may

include ultrasound, genetic testing, and amniocentesis Postmortem testing can be done for evidentiary

or forensic purposes, organ transplantation, or death reporting (autopsy) Clinical responsibilities and

interventions cover all three phases of the testing process: the pretest, intratest, and posttest periods

The clinician who provides diagnostic services must have basic requisite knowledge to plan patient

N OT E

● Overview of the Clinician’s Role

TABLE 1.1 Examples of Selecting Tests

Diagnostic Test Indication

Stool occult blood, fecal

occult blood testing

Yearly screening after 50 years of ageSerum potassium Yearly in patients taking diuretic agents or potassium

supplements; in cases of some cardiac arrhythmiasLiver enzyme levels Monitor patient taking hepatotoxic drugs; establish baseline values

Serum amylase In the presence of abdominal pain, suspect pancreatitis

Thyroid-stimulating hormone

(TSH) test

Suspicion of hypothyroidism, hyperthyroidism, or thyroid dysfunction in patients 50 years of age

Chlamydia and gonorrhea In sexually active persons with multiple partners; monitor for

pelvic inflammatory diseaseHematocrit and hemoglobin Baseline study; abnormal bleeding; detection of anemia

(use complete blood count [CBC] results if they are recent)Cervical Papanicolaou

(Pap) test

Yearly for all women 18 years of age; more often with high-risk factors (e.g., dysplasia, HIV, herpes simplex); check for human papillomavirus (HPV), chlamydia, and gonorrhea using DNA

Syphilis serum fluorescent

treponemal antibody (FTA) test

Positive rapid plasma reagin (RPR) test result

Tuberculosis (TB) skin test Easiest test to use for TB screening of individuals 35 years of

age or those with history of negative TB skin tests; for persons

in resident homesTuberculosis (TB) blood test Blood test to assess TB exposure in risk population

QuantiFERON Gold TB

Fasting blood glucose (FBG) Every 3 years starting at 45 years of age; hemoglobin A1c to

monitor diabetes controlUrinalysis (UA) Signs or history of recurrent urinary tract disease; incontinence;

pregnant women; men with prostatic hypertrophyProthrombin time (PT) (INR) Monitoring anticoagulant treatment

Prostate-specific antigen (PSA)

and digital rectal examination Screen men 50 years of age for prostate cancer yearly

Chest x-ray Monitor for lung lesions and infiltrates; congestive heart failure;

anatomic deformities, after trauma, before surgery, follow-up for positive TB skin test and monitor treatment

Mammogram Screen by 40 years of age in women, then every 12–18 months

between 40 and 49 years of age, annually at 50 years of age;

follow-up for history and treatment of breast cancer; routine screening when strong family history of breast carcinomaColon x-rays, flexible

sigmoidoscopy after 5 years,

and colonoscopy after 10 years

Screen adults for colon cancer beginning at age 50 years;

follow for presence of hemoglobin- or guaiac-positive stools, polyps, diverticulosis

table continues on pg 4 >

4 C H A P T E R 1 ● Overview of the Clinician’s Role

care and an understanding of psychoneuroimmunology (effects of stress on health status), make careful

judgments, and gather vital information about the patient and the testing process to diagnose

appropri-ately within the parameters of the clinician’s professional standards (Table 1.2; Chart 1.2)

The diagnostic testing model incorporates three phases: pretest, intratest, and posttest (Fig 1.1)

Laboratory terminology uses the terms preanalytical, analytical, and postanalytical

The clinical team actively interacts with the patient and his or her significant others throughout each

phase The following components are included with each laboratory test or diagnostic procedure in this text:

Pretest Interventions:

1 Test background information

2 Reference (normal) values

3 Explanation of test

4 Indications for testing

5 Signs, symptoms, and history of disease

Intratest Interventions:

1 Actual description of procedures

2 Proper specimen collection and transport

N OT E

A Clear evidence from all appropriately Measure plasma glucose through an

B Supportive evidence from well- Draw fasting blood plasma specimens

conducted studies or registries for glucose analysis

C No published evidence; or only case, Self-monitoring of blood glucose may

observational, or historical evidence help to achieve better control

E Expert consensus or clinical Measure ketones in urine or blood to

experience or Internet polls monitor and diagnose diabetic

CHART 1.1 Grading Guidelines for Scientific Evidence

tissue, or semen samples

Gather postmortem evidence, in certain criminal cases;

establish identity and parentageOther genetic tests Assist in establishing or ruling out familial inheritable diseases

Some tests are mandated by government agencies (e.g., U.S Preventive Services Task Force) or clinical practice guidelines of professional

societies (e.g., American Congress of Obstetricians and Gynecologists); others are deemed part of necessary care based on the individual

practitioner’s judgment and expertise, primary clinician, or a group practitioner consensus There is not a consensus as to the frequency of

testing (e.g., annually or after a certain age) Some will commonly be ordered at point of care.

● Overview of the Clinician’s Role

3 Gathering and using right equipment

4 Clinical implications of abnormal results

5 Interfering factors that clinician or patient can or cannot control (e.g., age, gender) and avoid (e.g., medications)

Posttest Interventions:

1 Patient monitoring

2 Clinical and procedure alerts

3 Special cautions

4 Interpretation of test results

5 Treatment, medical, surgery, follow-up

Each phase of testing requires that a specific set of guidelines and standards be followed for rate, optimal test results Patient care standards and standards of professional practice are key points

accu-in developaccu-ing a collaborative approach to patient care duraccu-ing diagnostic evaluation Standards of care provide clinical guidelines and set minimum requirements for professional practice and patient care They protect the public against less-than-quality care (Table 1.3)

TABLE 1.2 Examples of Inappropriate Tests and Replacement Tests

Crossmatch (needed if blood is actually to be given) Type and screen

ANA, antinuclear antibody; AST, aspartate transaminase; CBC, complete blood count; CRP, C-reactive protein; ESR, erythrocyte

sedimenta-tion rate; GGT, gamma-glutamyltransferase; HCV, hepatitis C virus; PCR, polymerase chain reacsedimenta-tion; PSA, prostate-specific antigen.

Provide patient-centered care

Manage testing environment using collaborative approach

Communicate effectively and clearly

Prepare the patient properly

Follow standards

Consider culture, gender, and age diversity

Perform and assist with diagnostic tests

Measure and evaluate outcomes; modify treatment as necessary

Manage effective diagnostic services using team approach

Interpret, treat, monitor, and counsel about meaning of or abnormal test outcomes

Identify clinical crisis

Maintain proper test records

Report per institution and government guidelines

CHART 1.2 Basics of Informed Diagnostic Care Before, During, and After Tests

Note: Informed care is evidence-based care and uses clinical decision-making rules.

6 C H A P T E R 1 ● Overview of the Clinician’s Role

Pretest Interventions

Know test terminology

Translate into language patient understands

Assess for test indications, interferences,

contraindications; identify risk-prone patients

and modify care plan

Obtain informed consent

Order appropriate tests correctly

Prepare and educate patient and family

Consider ethical and legal aspects

Support patient and/or family

Document, report, and maintain proper

records

Intratest Interventions

Follow regulatory standards and institutional

policies

Perform/assist with procedure

Collect and transport specimens

Observe standard/universal precautions

Provide physical support and reassure

Prevent and/or treat complications

Report, document, and maintain proper records

Posttest Interventions

Interpret test results; if abnormal, assess pretest compliance

Know and treat critical values

Monitor for posttest sedation and complications

Follow infection control guidelines

Provide social support and counsel for unexpected outcomes

Order follow-up tests at appropriate intervals and inform patient

Re-educate patient for future testing

Evaluate the effectiveness of managed care outcomes

Summarize diagnostic care

Document and maintain proper records and report results to the patient and clinician as mandated by government

Help patient integrate test results into lifestyle

Diagnostic Testing Process, Patient-Centered Care, and Services Model

Clinical Team

Intratest Phase Analytical (Procedural Care or Specimen Collection)

Posttest Phase

Postanalytical(P atient Aftercare)

Pretest PhasePreanalytical(Patient Preparation)

FIGURE 1.1 A model for the role of the clinical team in diagnostic care and services Diagnostic care and

services are performed safely and effectively in all three phases

Professional practice parameters of American Nurses Association (ANA), American Medical Association (AMA), American Society for Clinical Pathology (ASCP), American College of Radiology, Centers for Disease Control and Prevention (CDC), and The Joint Commission health care practice requirementsUse a model as a framework for choosing the proper test or procedure and in the interpretation of test results Use laboratory and diagnostic procedures for screening, differential diagnoses, follow-up, and case management.

Test strategies include single tests or combinations or panels of tests Panels can be performed in parallel, series, or both Patient education and proper patient preparation are involved

The guidelines of the major agencies, such as American Heart Association (e.g., stress tests after abnormal electrocardio- gram [ECG]), American Cancer Society (e.g., colonoscopy for colon cancer), and American Diabetes Association (e.g., hemoglobin A

Order the correct test; appropriately collect and transport specimens Properly perform tests in an accredited laboratory or diagnostic facility Accurately report test results Communicate and interpret test findings Treat or monitor the disease and the course of therapy Provide diagnosis as well as prognosis

Patients receive diagnostic services based on a documented assessment of need for diagnostic evalu- ation Patients have the right to necessary information, benefits, or rights to enable them to make choices and decisions that reflect their need or wish for diagnostic care

Individual agency and institution policies and procedures and quality control criteria for specimen collection, procedure state- ment for monitoring the patient after an invasive procedure, and policy for universal witnessed consent situations Statements on quality improvement standards Use standards of professional practice and standards of patient care Use policy for obtaining informed consent or wit- nessed consent Use policies for unusual situations

Observe standard precautions (formerly known as universal precautions) Use latex allergy protocols and required methodology of specimen collection Use standards and statements for monitoring patients who receive sedation and analgesia Vital signs are monitored and recorded at specific times before and after the procedure Patients are monitored for bleed- ing and respiratory or neurovascular changes Record data regarding outcomes when defined care criteria are implemented and practiced Protocols to obtain appropriate consents are employed, and deviations from basic consent policies are documented and reported to the proper individual

The clinician wears protective eyewear and gloves when handling all body fluids and employs proper handwashing before and after handling specimens and between patient contacts Labeled biohazard bags are used for specimen transport Vital signs are monitored and recorded at specific times before and after the procedure Patients are monitored for bleeding and respiratory or neurovascular changes Record data regarding outcomes when defined care criteria are implemented and practiced Protocols to obtain appro- priate consents are employed, and deviations from basic consent policies are documented and reported to the proper individual

8 C H A P T E R 1 ● Overview of the Clinician’s Role

A may not handle food or care for patients, young children, or elderly people for a specific period of time Federal government regulates shipment of diagnostic specimens Magnetic resonance imaging and computed tomography are used to evaluate persistent low back pain according to AHRQ guidelines

situations (e.g., following a motor vehicle crash, homicide, or suicide or in an unconscious individual)

Properly trained personnel perform blood, saliva, and breath alcohol testing and use required kits as referenced by federal law

Occupational Safety and Health Administration (OSHA)The clinician is properly trained, under mandated guidelines, to administer employee medical surveillance

Properly trained personnel perform respirator qualification, fit testing, and monitoring for toxic exposure

Clinical and Laboratory Standards Institute (CLSI)Develops standards and guidelines for laboratory testing Standards are documents that define specific materials, methods, and practices as they relate to laboratory specimen tests Guidelines are documents that describe essential criteria for a procedure that can be modified by the user to fit his or her needs

Provides health care professionals with practical guidelines for consistency in procedural methods in laboratory testing

● Overview of the Clinician’s Role

If test results are inconclusive or negative and no definitive medical diagnosis can be established, other tests and procedures may be ordered Thus, testing can become an involved and lengthy process

In the future, digital pathology and computerized algorithms may be helpful to the clinician when it comes to diagnosis and directed treatment

Understanding the basics of safe, effective, and informed care is important These basics include assessing risk factors and modifying care accordingly, using a collaborative approach, following proper guidelines for procedures and specimen collection, and delivering appropriate care throughout the process Providing reassurance and support to the patient and his or her significant others, intervening appropriately, and clearly documenting patient teaching, observations, and outcomes during the entire process are important (see Fig 1.1)

A risk assessment before testing identifies risk-prone patients and helps to prevent complications The following factors increase a patient’s risk for complications and may affect test outcomes:

1 Age  65 years: decrease/increase for expected test outcomes

2 History of falls

3 History of serious chronic illnesses

4 History of allergies (e.g., latex, contrast iodine, radiopharmaceuticals, and other medications)

5 Infection or increased risk for infection (e.g., HIV, organ transplantation, chemotherapy, radiation therapy)

6 Aggressive or antisocial behavior

7 Seizure disorders

8 Uncontrolled pain

9 Gastric motility dysfunction

10 Use of assistive devices for activities of daily living (ADLs)

11 Unsteady gait, balance problems

12 Neuromuscular conditions

13 Weakness, fatigability

14 Paresthesias

15 Impaired judgment or illogical thinking

16 Severe visual problems

17 Hearing impairment

18 Use of diuretics, sedatives, analgesics, or other prescription or over-the-counter (OTC) drugs

19 Alcohol or illegal drug use or addiction

The environments in which diagnostic services are provided, the degree of cultural diversity ent in the community, and the physical, emotional, social, and spiritual state of the patient all influence the patient’s response to the procedure Including the patient’s significant others is a vital component

pres-of the entire process and must not be taken lightly or casually dismissed

New and emerging changes are occurring in the health care field, such as telemedicine, ized medicine (using one’s own genetic makeup to manage their disease), and nanomedicine (treating disease at the molecular level) In the future, online resources (e.g., eMedicine) may be used by the physician where traditional clinical resources may be limited New guidelines focus on evidence-based practice—for example, using pH test papers to confirm correct nasogastric tube placement (pH  4.0) rather than having to rely on an x-ray procedure When a patient is admitted to the emergency depart-ment with chest pain, a whole blood specimen for cardiac troponin is collected on arrival and 6 hours later, thereby replacing CK-MB measurement Recent Laboratory Medicine Practice Guidelines (LMPGs) have addressed diabetes, liver tumor markers, pharmacogenetics, and newborn screening (National Academy of Clinical Biochemistry, American Association for Clinical Chemistry) The emerg-ing field of metabolomics (analysis of metabolites) has been increasingly used to identify biomarkers

Although patient populations and testing environments vary, the potential contagions are universal

and of concern for both the patient and the health care worker Standard and universal precautions must be used in all testing environments to ensure safety for patients and clinicians Certain tests

10 C H A P T E R 1 ● Pretest Phase: Elements of Safe, Effective, Informed Care

(e.g., cholesterol screening, blood glucose, electrocardiogram [ECG], lipid profiles, tuberculosis [TB]

skin tests) can be done in the field, meaning that the service is brought to the patient’s environment

Other tests (e.g., x-rays using contrast media and those that require special patient preparation,

inva-sive procedures, nuclear medicine procedures, hormone levels, and 24-hour urine testing panels)

must be done in a physician’s office, clinic, or hospital setting Magnetic resonance imaging (MRI) and

ultrasound procedures (e.g., echocardiograms) are commonly performed in freestanding or specialty

diagnostic centers Complex tests such as endoscopic retrograde cholangiopancreatography (ERCP),

cardiac catheterization, and bronchoscopy may require hospital admission or at least outpatient status

As testing equipment becomes more technologically sophisticated and risks associated with testing

are reduced, the environment in which diagnostic procedures take place will also shift Insurance

reimbursement for testing also influences trends Managed care and case management, together with

collaboration among the diverse health care disciplines and the patient, are key factors in determining

how and to what degree optimal diagnostic services are used Clear, timely, accurate communication

among all patients and professionals is key to minimizing problems and frustrations

As societies become more culturally blended, the need to appreciate and work within the realm of

cultural diversity becomes imperative Interacting with patients and directing them through diagnostic

testing can present certain challenges if one is not familiar with and sensitive to the health care belief

system of the patient and his or her significant others Something as basic as attempting to

commu-nicate in the face of language differences may necessitate arrangements for a relative or translator to

be present during all phases of the process Special attention and communication skills are necessary

for these situations as well as when caring for children and for comatose, confused, or frail patients

Consideration of these issues will significantly influence compliance, outcomes, and positive responses

to the procedure To be most effective, professional care providers must be open to a holistic

perspec-tive and attitude that affects their caregiving, communication, and patient-empowering behaviors

Clinicians who understand the patient’s basic needs and expectations and strive to accommodate those

as much as possible are truly acting as patient advocates

Preparing patients for diagnostic or therapeutic procedures, collecting specimens, carrying out and

assisting with procedures, and providing follow-up care have long been requisite activities of

profes-sional practice This care may continue even after the patient’s death Diagnostic postmortem services

include death reporting, possible postmortem investigations, and sensitive communication with

griev-ing families and significant others regardgriev-ing autopsies, unexplained death, other postmortem testgriev-ing,

and organ donation (see Chapter 16)

Professionals need to work as a team to meet diverse patient needs, to facilitate certain decisions,

to develop comprehensive plans of care, and to help patients modify their daily activities to meet test

requirements in all three phases It is given that institutional protocols are followed

PRETEST PHASE: ELEMENTS OF SAFE, EFFECTIVE,

INFORMED CARE

The emphasis of pretest care is on appropriate test selection, obtaining proper consent, proper patient

preparation, individualized patient education, emotional support, and effective communication These

interventions are essential to achieving the desired outcomes and preventing misunderstandings and

errors

Basic Knowledge and Necessary Skills

Know the test terminology, purpose, process, procedure, and normal test reference values or results

The names of diseases are a convenient way of briefly stating the end point of a diagnostic process that

begins with assessment of symptoms and signs and ends with knowledge of causation and detection of

underlying disorders of structure and function

● Pretest Phase: Elements of Safe, Effective, Informed Care

The clinical value of a test is related to its sensitivity, its specificity, and the incidence of the disease

in the population tested Sensitivity and specificity do not change with different populations of ill and healthy patients

True positive: positive test result in a person with the disease

True negative: negative test result in a person without the disease

False positive: positive test result in a person without the disease

False negative: negative test result in a person with the disease

Specificity refers to the ability of a test to identify correctly those individuals who do not have the

disease The formula for specificity is as follows:

Specificity (%)  number of true negatives number of true negatives number of false positives  100

One-hundred percent specificity would indicate there are no false positives—that is, the test identifies all individuals who do not have the disease

Sensitivity refers to the ability of a test to correctly identify those individuals who truly have the

disease The formula for sensitivity is as follows:

Sensitivity (%)  number of true positives number of true positives number of false negatives  100

One-hundred percent sensitivity would indicate there are no false negatives—that is, the test

identi-fies all individuals with the disease as having the disease

Incidence refers to the number of new cases of a disease, during a specified period of time, in a

specified population or community

Prevalence refers to the number of existing cases of a disease, at a specific period of time, in a

given population

Predictive values refer to the ability of a screening test result to correctly identify the disease state

The predictive value of the same test can be very different when applied to people of differing ages,

gender, geographic locations, and cultures True-positive results correctly identify individuals who actually have the disease, and true-negative results correctly identify individuals who do not actually have the disease Positive predictive value equals the percentage of positive tests with true-positive results (i.e., the individual does have the disease) Negative predictive value refers to the percentage of

negative tests with true-negative results (i.e., the individual does not have the disease)

Positive predictive value  number of true positives number of true positives number of false positives  100Negative predictive value  number of true negatives number of true negatives number of false negatives  100 See Table 1.4 for an example that demonstrates the specificity, sensitivity, and predictive values for

a new screening test to identify the cystic fibrosis gene

Specificity (%)  341346 100  98.5%

Sensitivity (%)  6277 100  80.5%

N OT E

N OT E

12 C H A P T E R 1 ● Pretest Phase: Elements of Safe, Effective, Informed Care

Thus, this new screening test will give a false-negative result about 20% of the time (e.g., the person

does have the cystic fibrosis gene but his or her test results are negative)

Positive predictive value  6267  100  92.5%

Thus, there is about an 8% chance that the person will test positive for the cystic fibrosis gene but

does not have it

Negative predictive value  341346  100  98.5%

Thus, there is about a 1.5% chance that the person will test negative for the cystic fibrosis gene

but actually does have it

Look at both current and previous test results and review the most recent laboratory data first,

then work sequentially backward to evaluate trends or changes from previous data The patient’s plan

of care may need to be modified because of test results and changes in medical management

Testing Environments

Diagnostic testing occurs in many different environments Many test sites have shifted into community

settings and away from hospitals and clinics

Point-of-care testing (POCT) refers to medical testing done in close proximity to the site of patient care

(e.g., in the primary care setting or acute care settings [emergency room, critical care units, ambulances]),

thus moving toward decentralized testing Recently, manufacturers of POCT devices have made

inroads into physician offices, off-site clinics, and pharmacies POCT is convenient for the patient,

pro-duces rapid reporting of test results, and allows for more timely assessment, management, and treatment

Testing in the home care environment requires skill in procedures such as drawing blood samples,

collecting specimens from retention catheters, proper specimen labeling, documentation, specimen

handling, and specimen transporting Moreover, teaching the patient and his or her significant others

how to collect specimens is an important part of the process

In occupational environments, testing may be done to reduce or prevent known workplace hazards

(e.g., exposure to lead) and to monitor identified health problems This can include pre-employment

baseline screening, periodic monitoring of exposure to potentially hazardous workplace substances,

and drug screening Skill in drawing blood samples, performing breathing tests, monitoring chain of

custody (see Chapter 3), and obtaining properly signed and witnessed consent forms for drug, genetic,

and HIV testing is required

More pretest, posttest, and follow-up testing occurs in nursing homes and long-term care facilities

because patients are frequently taken or transferred to hospitals for more complex procedures (e.g.,

computed tomography [CT] scans, endoscopies), whereas this is not the case with routine testing

Increasing numbers of full code (i.e., resuscitation) orders lead to greater numbers and varieties of

tests Additionally, confused, combative, or uncooperative behaviors are seen more frequently in these

settings An attitude adopted by nursing home patients of not wanting to be bothered or engaging in

outright refusal to undergo prescribed tests can make testing difficult Consequently, understanding

TABLE 1.4 Sample Test Results

Test Result Have Gene for Cystic Fibrosis Do Not Have Gene for Cystic Fibrosis Total

● Pretest Phase: Elements of Safe, Effective, Informed Care

patient behaviors and using appropriate communication strategies and interventions for this population are necessary skills for practicing in this arena

For those who practice in the realm of public health, diagnostic test responsibilities focus on wellness screenings, preventive services, disease control, counseling, and treatment of individuals with problems Case finding frequently occurs at health fairs, outreach centers, homeless shelters, neighborhood nurse offices, mobile health vans, and church settings Responsibilities vary according

to setting and may include providing test information, procuring specimens, and recommending rals to appropriate caregivers These responsibilities may even extend to transporting and preparing specimens for analysis or actually performing specimen analysis (e.g., stool tests for occult blood, TB skin testing, and procuring blood or saliva samples for HIV/AIDS testing)

History and Assessment

Obtain a relevant, current health history; perform a physical assessment if indicated Identify ditions that could influence the actual testing process or test outcomes (e.g., pregnancy, diabetes, cultural diversity, language barrier, physical impairment, altered mental state)

1 Perform a risk assessment for potential injury, adverse event, or noncompliance

2 Identify contraindications to testing such as allergies (e.g., iodine, latex, medications, contrast media) Records of previous diagnostic procedures may provide clues

3 Assess for coping styles and knowledge or teaching needs

4 Assess fears and phobias (e.g., claustrophobia, panic attack, fear of needles and blood) Ascertain what strategies the patient uses to deal with these reactions and try to accommodate these

5 Observe standard/universal precautions with every patient (see Appendix A) A patient may choose not to disclose drug or alcohol use or HIV and hepatitis risks

6 Document relevant data Address patient concerns and questions This information adds to the database for collaborative problem-solving activities among the medical, laboratory-diagnostic, and nursing disciplines

Laboratory tests used to assess a patient’s wellness or confirm a diagnosis are varied For

exam-ple, type 2 diabetes mellitus affects an estimated 26 million Americans, and 90% of these cases

are preventable with a healthy lifestyle Therefore, monitoring fasting serum glucose levels in older

adults and in obese teenagers and young adults is indicated Furthermore, if the serum level is 100

to 125 mg/dL (6.1 to 6.9 mmol/L), a test for glycosylated hemoglobin (HbA1c) would be considered

C L I N I C A L A L E R T

Reimbursement for Diagnostic Services

Differences in both diagnostic care services and reimbursement may vary between private and ment insurance Nonetheless, quality of care should not be compromised in favor of cost reduction Advocate for patients regarding insurance coverage for diagnostic services Inform the patient and his or her family or significant others that it may be necessary to check with their insurance company before laboratory and diagnostic testing to make certain that costs are covered

Many insurance companies employ case managers as gatekeepers for monitoring costs, diagnostic tests ordered, and other care As a result, the insurance company or third-party payer may reimburse only for certain tests or procedures or may not cover tests considered by them to be preventive care

So that reimbursement completely covers diagnostic services provided, be sure to include proper documentation (e.g., date of laboratory service and specimen collected) and proper current procedural terminology (CPT) codes Chart 1.3 lists laboratory tests that are covered by most insurance carriers, both private and government

14 C H A P T E R 1 ● Pretest Phase: Elements of Safe, Effective, Informed Care

Methodology of Testing

Follow testing procedures accurately Verify orders and document them with complete, accurate,

and legible information Document all drugs the patient is taking because these may influence test

outcomes (see Appendix E)

1 Ensure that specimens are correctly obtained, preserved, handled, labeled, and delivered to the

appropriate department For example, it is not generally acceptable to draw blood samples when

an intravenous line is infusing proximal to the intended puncture site

2 Observe precautions for patients in isolation Use standard/universal precautions or other

transmission-based precautions as dictated by infection control policies of the institution

3 Health care personnel should protect themselves, as appropriate, through the use of personal

protective equipment (PPE) Standards have been developed and implemented in an effort to

prevent the transmission of blood-borne pathogens from patients to health care workers Training

and education can only be effective when health care professionals are continually diligent about

safety

4 As much as possible, coordinate patient activities with testing schedules to avoid conflicts

with meal times and administration of medications, treatments, or other diagnostic tests and

travel time

a Maintain NPO (i.e., Latin: non per os , nothing by mouth) status when necessary

b Administer the proper medications in a timely manner Schedule tests requiring contrast

substances in the proper sequence so as not to invalidate succeeding tests

Alpha-fetoprotein

Blood counts

Blood glucose testing

Carcinoembryonic antigen

Collagen crosslinks, any method (urine osteoporosis)

Digoxin therapeutic drug assay

Fecal occult blood

Gamma-glutamyltransferase

Glycated hemoglobin/glycated protein

Hepatitis panel

HIV testing (diagnosis)

HIV testing (prognosis including monitoring)

Human chorionic gonadotropin

Tumor antigen by immunoassay—CA125

Tumor antigen by immunoassay—CA15-3/CA27

Tumor antigen by immunoassay—CA19-9

Urine culture

CHART 1.3 Tests Covered By Most Insurance Carriers

● Pretest Phase: Elements of Safe, Effective, Informed Care

Interfering Factors

Minimize test outcome deviations by following proper test protocols Make certain the patient and his

or her significant others know what is expected of them Written instructions are very helpful

Reasons for deviations may include the following:

1 Incorrect specimen collection, handling, storage, or labeling

2 Wrong preservative or lack of preservative

3 Delayed specimen delivery

4 Incorrect or incomplete patient preparation

5 Hemolyzed blood samples

6 Incomplete sample collection, especially of timed samples

7 Old or deteriorating specimens

Patient factors that can alter test results may include the following:

1 Incorrect pretest diet

2 Current drug therapy

3 Type of illness

4 Dehydration

5 Position or activity at time of specimen collection

6 Postprandial status (i.e., time patient last ate)

7 Time of day

8 Pregnancy

9 Level of patient knowledge and understanding of testing process

10 Stress

11 Nonadherence or noncompliance with instructions and pretest preparation

12 Undisclosed drug or alcohol use

13 Age and gender

Avoiding Errors

To avoid costly mistakes, know what equipment and supplies are needed and how the test is formed Communication errors account for more incorrect results than do technical errors Properly identify and label every specimen as soon as it is obtained With the use of bar code technology, tran-scription error rates have substantially decreased and data entry is much quicker and more accurate Determine the type of sample needed and the collection method to be used Additionally, the follow-ing should also be considered:

• Is the test invasive or noninvasive?

• Are contrast media injected or swallowed?

• Is there a need to fast?

• Are fluids restricted or forced?

• Are medications administered or withheld?

• What is the approximate length of the procedure?

• Are consent forms properly completed?

• Is a local anesthetic, conscious sedation, oxygen, analgesia, or anesthesia required?

Report test results as soon as possible Critical values must be reported immediately (STAT, Latin:

statim ) to the appropriate health care provider (e.g., physician, nurse, or physician assistant [PA]),

depending on institutional policy

Instruct patients and their significant others regarding their responsibilities Accurately outline the steps of the testing process and any restrictions that may apply Conscientious, clear, timely communi-cation among health care departments can reduce errors and inconvenience to both staff and patients

16 C H A P T E R 1 ● Pretest Phase: Elements of Safe, Effective, Informed Care

Proper Preparation

Prepare the patient correctly This preparation begins at the time of scheduling and extends to the

testing facility

1 Provide information about the testing site and give directions for locating the facility; allow time

to enter the facility and find the specific testing laboratory If a copy of the written test order was

given to the patient to bring to the laboratory, interpret the test order

2 Plan to be at the department 15 minutes before testing if the test is scheduled for a specific time Upon

arrival, the patient needs to be properly identified by at least two identifiers (e.g., asking the patient

to spell their last name and providing their date of birth) Once proper identification has been

con-firmed, the patient should review any preprinted labels that may be used to label lab specimens and/or

wristband if appropriate Review all pretest instructions and be certain they are explained clearly (e.g.,

explain to the patient what fasting actually means if the patient is given fasting directions for a test)

3 Be cognizant of special needs of the patient with physical limitations or disabilities, ostomies, or

diabetes; children; elderly patients; and culturally diverse patients

4 Give simple, accurate, precise instructions (scripted) according to the patient’s level of

understand-ing For example, the patient needs to know when and what to eat and drink or how long to fast

5 Encourage dialogue about fears and apprehensions “Walking” a patient through the procedure

using imagery and relaxation techniques may help the patient to cope with anxieties Never

under-estimate the value of a caring presence

6 Assess for the patient’s ability to read and understand instructions Poor eyesight or hearing difficulties

may impair understanding and compliance Speak slowly and clearly Do not bombard the patient with

information Instruct the patient to use assistive devices such as eyeglasses and hearing aids if

neces-sary Clear, written instructions can reinforce verbal instructions and should be used whenever

pos-sible In some cases, a translator, sign language interpreter, or legal representative may be necessary

7 Assess for language and cultural barriers Patients behave according to personal values,

percep-tions, beliefs, tradipercep-tions, and cultural and ethnic influences Take these into consideration and value

the patient’s uniqueness to the highest degree possible

8 Document accurately in all testing phases

Patient Education

Educate the patient and family regarding the testing process and what will be expected of them Record

the date, time, type of teaching, information given, and person to whom the information was given

1 Giving sensory and objective information that relates to what the patient will likely physically feel

and the equipment that will be used is important so that patients can envision a realistic

representa-tion of what will occur Avoid technical and medical jargon and adapt informarepresenta-tion to the patient’s

level of understanding Slang terms may be necessary to get a point across

2 Encourage questions and verbalization of feelings, fears, and concerns Do not dismiss, minimize, or

invalidate the patient’s anxiety through trivial remarks such as “Don’t worry.” Develop listening skills

and be aware of nonverbal signals (i.e., body language) because these frequently provide a more

accu-rate picture of what the patient really feels than what he or she says Above all, do not be judgmental

3 Emphasize that there is usually a waiting period (i.e., turn-around time) before test results are

relayed back to the clinicians and nursing unit The patient may have to wait several days for results

Offer listening, presence, and support during this time of great concern and anxiety

4 Record test result information Include the patient’s response Just because something is taught

does not necessarily mean that it is learned or accepted The possibility that a diagnosis will require

a patient to make significant lifestyle changes (e.g., diabetes) requires intense support,

understand-ing, education, and motivation Document specific names of audiovisual and reading materials to

be used for audit, reimbursement, and accreditation purposes

Patient Independence

Allow the patient to maintain as much control as possible during the diagnostic phases to reduce stress and anxiety Include the patient and his or her significant others in decision making Because of factors such as anxiety, language barriers, and physical or emotional impairments, the patient may not fully understand and assimilate instructions and explanations To validate the patient’s understanding of what is presented, ask the patient to repeat instructions given to evaluate assimilation and understand-ing of presented information

Include and reinforce information about the diagnostic plan, the procedure, time frames, and the patient’s role in the testing process

Test Results

It is important to understand normal or reference values/intervals and ranges

1 Normal ranges can vary to some degree from laboratory to laboratory Frequently, this is because of

the particular type of equipment used Theoretically, normal can refer to the ideal health state, to

average reference values or intervals, or to types of statistical distribution Normal values are those that fall within two standard deviations (i.e., random variation) of the mean value for the normal population The reference interval typically represents the upper and lower limits wherein 95% of healthy people would fall Although establishing normal or reference values is complex, it is much more so in the pediatric population There are many challenges related to sex- and age-specific reference intervals in the pediatric population

2 The reported reference range for a test can vary according to the laboratory used, the method employed, the population tested, and methods of specimen collection and preservation

3 Most normal blood test values are determined by measuring fasting specimens

4 Specific factors can influence test results For example, patient posture is important when plasma volume is measured because this value is 12% to 15% greater in a person who has been supine for several hours Changing from a supine to a standing position can alter values as follows: increased hemoglobin (Hb), red blood cell (RBC) count, hematocrit (Hct), calcium (Ca), potassium (K), phosphorus (P), aspartate aminotransferase (AST), phosphatases, total protein, albumin, choles-terol, and triglycerides Going from an upright to a supine position results in increased hematocrit, calcium, total protein, and cholesterol A tourniquet applied for more than 1 minute produces labo-ratory value increases in protein (5%), iron (6.7%), AST (9.3%), and cholesterol (5%) and decreases

in K  (6%) and creatinine (2% to 3%)

Laboratories must specify their own normal ranges Many factors affect laboratory test values and influence ranges Thus, values may be normal under one set of prevailing conditions but may exhibit different limits in other circumstances Age, gender, race, environment, posture, diurnal and other cyclic variations, foods, beverages, fasting or postprandial state, drugs, and exercise can affect derived values Interpretation of laboratory results must always be in the context of the patient’s state of being Circumstances such as hydration, nutrition, fasting state, mental status, or compliance with test proto-cols are only a few of the situations that can influence test outcomes

18 C H A P T E R 1 ● Pretest Phase: Elements of Safe, Effective, Informed Care

Laboratory Reports

Scientific publications and many professional organizations are changing clinical laboratory data values

from conventional units to Système International (SI) units Currently, many data are reported in

both ways

The SI system uses seven dimensionally independent units of measurement to provide logical and

consistent measurements For example, SI concentrations are written as amount per volume (moles or

millimoles per liter) rather than as mass per volume (grams, milligrams, or milliequivalents per deciliter,

100 milliliters, or liter) Numerical values may differ between systems or may be the same For example,

chloride is the same in both systems: 95 to 105 mEq/L (conventional) and 95 to 105 mmol/L (SI)

Converting to Système International Units

Clinical laboratory data may be reported in conventional units, SI units, or both Examples of

conver-sion of data from the two systems are included in Table 1.5 To convert SI units to conventional U.S

units, divide by the factor; to convert conventional US units to SI units, multiply by the factor

Example:

To convert a digoxin (drug management) level of 0.6 nmol/L (SI units), divide by the factor 1.281 to

obtain conventional units of 0.5 ng/dL

To convert a Ca 2  (electrolyte) value of 8.6 mg/dL (conventional units), multiply by the factor 0.2495

to obtain the SI units of 2.15 mmol/L

Margins of Error

Recognize margins of error For example, if a patient has a battery of chemistry tests, the possibility

exists that some tests will be abnormal owing purely to chance This occurs because a significant margin

of error arises from the arbitrary setting of limits Moreover, if a laboratory test is considered normal up

to the 95th percentile, then 5 times out of 100, the test will show an abnormality even though a patient

is not ill A second test performed on the same sample will probably yield the following: 0.95  0.95,

or 90.25% This means that 9.75 times out of 100, a test will show an abnormality even though the

person has no underlying health disorder Each successive testing will produce a higher percentage of

abnormal results If the patient has a group of tests performed on one blood sample, the possibility that

some of the tests will read abnormal due purely to chance is not uncommon

Ethics and the Law

Consider legal and ethical implications These include the patient’s right to information, correct

diag-nosis and progdiag-nosis, properly signed and witnessed consent forms, and explanations and instructions

regarding chain-of-custody requirements and risks as well as benefits of tests

1 Chain of custody is a legal term descriptive of a procedure to ensure specimen integrity from

col-lection, to transport, to receipt, to analysis and specimen storage A special form is used to provide

a written record The right to informed consent before certain tests and procedures pertains to

patient autonomy, the ethical right of self-determination, the legal right to be free of procedures

to which one does not consent, and the right to determine what will be done to one’s own person

Risks, benefits, and alternatives are explained and written consent obtained well in advance of the

procedure

2 The patient must demonstrate appropriate cognitive and reasoning faculties to sign a legally valid

consent Conversely, a patient may not legally give consent while under the immediate influence of

sedation, anesthetic agents, or certain classes of analgesics and tranquilizers If the patient cannot

validly and legally sign a consent form, an appropriately qualified individual may give consent for

the patient

20 C H A P T E R 1 ● Pretest Phase: Elements of Safe, Effective, Informed Care

22 C H A P T E R 1 ● Pretest Phase: Elements of Safe, Effective, Informed Care

3 Guidelines and wishes set forth in advance directives or living will–type documents must be

honored, especially in life-threatening situations Such directives may prevent more sophisticated

invasive procedures from being performed Some states have legislated that patients can procure

do-not-resuscitate (DNR) orders and medical DNR bracelets that indicate their wishes A copy

of a patient’s advance directives in the health care record can be very helpful in unpredictable

situations

4 A collaborative team approach is essential for responsible, lawful, and ethical patient-focused

care The clinician who orders the test has a responsibility to inform the patient about risks and

test results and to discuss alternatives for follow-up care Other caregivers can provide additional

information and clarification and can support the patient and family in achieving the best possible

outcomes The duty to maintain confidentiality, to provide freedom of choice, and to report

infec-tious diseases may result in ethical dilemmas For example, a dilemma to be faced in diagnostic

testing surrounds HIV screening: Should it be risk based or routine?

5 When faced with ethical dilemmas, choosing the correct course of action is a challenge The

responsibility to provide safe, effective care may conflict with the ethics of privacy, confidentiality,

quality of life, and patient safety The Health Insurance Portability and Accountability Act (HIPAA)

of 1996 has set forth regulations regarding patient confidentiality Protected health information

(PHI) is addressed under HIPAA regulations and includes any information—whether oral,

writ-ten, electronic, or recorded in any manner—that is created or received by a health care worker;

relates to the patient’s past, present, or future health care management; identifies the patient (e.g.,

Social Security number, medical record number); or can be used to identify a patient HIPAA also

provides rights to patients (e.g., the right to request, amend, correct, or limit their PHI)

Respect for the dignity of the individual reflects basic ethical considerations Patients and

fam-ily have a right to consent, to question, to request other opinions, and to refuse diagnostic tests

Conversely, caregivers have the right to know the diagnoses of the patients they care for so that they

can minimize the risks to themselves

Patient’s Bill of Rights and Patient Responsibilities

Patients have a right to expect that an agency’s or institution’s policies and procedures will ensure

certain rights and responsibilities for them At all times, the patient has the right

1 To considerate, honest, respectful care, with attention given to privacy and maintenance of

per-sonal dignity, cultural and perper-sonal values and beliefs, and physical and developmental needs,

regardless of the setting

2 To be involved in decision making and to participate actively, if so desired, in the testing process,

assuming the patient is competent to make these choices

3 To participate in the informed consent process before testing and to be told of the benefits, risks,

and reasonable alternative approaches to tests ordered

4 To be informed regarding test costs and reimbursement responsibility

5 To refuse diagnostic testing

6 To have ease in making an appointment

7 To expect to have the support and presence of family or significant others, if so desired and

appro-priate, during the testing process

8 To expect that standards of care will be followed by all personnel involved in the testing process

and to eliminate duplication of testing and information

9 To expect safe, skilled, quality care provided by trained personnel with expertise in their field

10 To expect patient and family education and instructions regarding all phases of the testing process

and procedure, including the nature and purpose of the test, pretest preparation, actual testing,

posttest care benefits, risks, side effects, and complications Information is provided in a sensitive

and objective manner

● Intratest Phase: Elements of Safe, Effective, Informed Care

11 To expect to have access to test results and to be informed in a timely manner of test results and implications, treatment, and future testing if necessary

12 To expect to be counseled appropriately regarding abnormal test outcomes as well as alternative options and available treatments

13 To expect to have acceptable pain control and comfort measures provided throughout the testing process

14 To expect that all verbal, written, and electronic communication; medical records; and health

care record transfers will be accurate and confidential Exception: when reporting of situation is required by law (e.g., certain infectious diseases, child abuse)

The patient has the following responsibilities:

1 To comply with test requirements (e.g., fasting, special preparations, medications, enemas) and to inform the clinician if they are unable to do so

2 To report active or chronic disease conditions that may alter test outcomes, be adversely affected

by the testing process, or pose a risk to health care providers (e.g., HIV, hepatitis)

3 To keep appointments for diagnostic procedures and follow-up testing

4 To disclose drug and alcohol use as well as use of supplements and herbal products despite being informed that these products could affect test outcomes (e.g., erroneous test results)

5 To disclose allergies and past history of sensitivity and complications or adverse reactions to tests

Example: reaction to contrast materials or latex allergy

6 To report any adverse effects attributed to tests and procedures after being advised regarding signs and symptoms of such

7 To supply specimens that are their own

8 To report visual or hearing impairments or inability to read, write, or understand English

9 To report use of performance-enhancing drugs

10 To inform tester of not understanding testing, necessity of test, and involvement in test process

Cultural Sensitivity

Preserving the cultural well-being of any individual or group promotes compliance with testing and easier recovery from routine as well as more invasive and complex procedures Sensitive questioning and observation may provide information about certain cultural traditions, concerns, and practices related to health For example, the Hmong people believe the soul resides in the head and that no one should touch

an adult’s head without permission Patting a Hmong child on the head may violate this belief Health care personnel should make an effort to understand the cultural differences of populations they serve without passing judgment Most people of other cultures are willing to share this information if they feel

it will be respected Sometimes, a translator is necessary for accurate communication

Many cultures have diverse beliefs about diagnostic testing that requires blood sampling For example, alarm about having blood specimens drawn or concerns regarding the disposal of body fluids

or tissue may require health care workers to demonstrate the utmost patience, sensitivity, and tact when communicating information about blood tests Using ethnographic interviewing helps to access meaningful patient cultural values, increases patient and family acceptance of diagnostic care, and shows respect for the social aspects of the diagnosis

INTRATEST PHASE: ELEMENTS OF SAFE, EFFECTIVE,

INFORMED CARE

Basic Knowledge and Required Skills

Intratest care focuses on specimen or tissue collection, monitoring the testing environment, performing

or assisting with procedures, providing emotional and physical comfort and reassurance, administering analgesics and sedatives, and monitoring vital signs and other parameters during testing The clinician

24 C H A P T E R 1 ● Intratest Phase: Elements of Safe, Effective, Informed Care

needs basic knowledge about the procedure and test and should have the required skills to perform

testing or to assist in the process Safe practices, proper collection of specimens, minimizing delays,

providing support to the patient, preparing or administering analgesia and sedatives,  monitoring

various bio-parameters as necessary, and being alert to potential side effects or complications are

inte-gral activities of the intratest phase Invasive procedures place patients at greater risk for complications

and adverse events and require ongoing vigilance and observation Monitoring fluid intake and loss,

body temperature, and respiratory and cardiovascular systems and treating problems in these domains

require critical thinking and quick responses

Infection Prevention

Institute accepted infection prevention and control protocols Observe special measures and sterile

techniques as appropriate Identify patients at risk for infection, such as immunocompromised patients

Initiate strict respiratory and contact isolation as necessary Quality assurance requires proper collection,

transport, and receipt of specimens and use of properly cleaned and prepared instruments and

equip-ment Appendix A offers more information on standard precautions for safe practice, infection control,

isolation, quarantine surveillance, and reporting The term standard precautions refers to a system of

dis-ease control that presupposes that each direct contact with body fluids or tissues is potentially infectious

and that every person exposed to these must protect himself or herself Consequently, health care

work-ers must be both informed and conscientious about adhering to standard precautions and strict infection

control guidelines It goes without saying that health care workers must be scrupulous about proper hand

hygiene According to the Centers for Disease Control and Prevention (CDC), proper hand hygiene must

be practiced before patient contact and before donning gloves, when inserting catheters or other devices

that do not require surgery, and after contact with a patient’s skin, body fluids, or wound dressings and

after removing gloves Proper protective clothing and other devices, or PPE, must be worn as necessary

Procurement and disposal of specimens according to U.S Occupational Safety and Health

Administration (OSHA) standards must be adhered to Moreover, institutions may have procedures and

policies of their own to ensure compliance (e.g., specimens are to be placed directly into biohazard bags)

Standard precautions prevail in all situations in which risk for exposure to blood, tissue,

and other body fluids is even remotely possible

Communicable diseases subject to quarantine include cholera, diphtheria, infectious

TB, plague, yellow fever, smallpox, viral hemorrhagic fevers (e.g., Lassa, Marburg, Ebola), and

severe acute respiratory syndrome (SARS) Individuals are quarantined in an effort to reduce the

transmission or spread of communicable diseases

Collaborative Approaches

A collaborative team approach is necessary for most procedures Clinicians must assist and

under-stand each other’s roles in the procedure Invasive procedures (e.g., lumbar punctures, cystoscopy)

place patients at greater risk for complications and usually require closer monitoring during the test

Frequently, administration of intravenous (IV) sedation and other drugs is part of the procedure

Astute ongoing observation of the patient and critical thinking and quick decision-making skills during

intense situations are requisites for clinicians in these settings

Risk Management

Assess for and provide a safe environment for the patient at all times Identify patients at risk and

environments that may pose a risk Previous falls, cerebrovascular accident (CVA), neuromuscular

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