Laboratory Hemostasis: A Practical Guide for Pathologists

210 Pages·2015·3.811 MB·English

by  Sterling T. Bennett, Christopher M. Lehman, George M. Rodgers (auth.)

Laboratory
Hemostasis
A Practical Guide
for Pathologists
Second Edition
Sterling T. Bennett
Christopher M. Lehman
George M. Rodgers
123
Laboratory Hemostasis

Sterling T. Bennett (cid:129) Christopher M. Lehman
George M. Rodgers
Laboratory Hemostasis
A Practical Guide for Pathologists
Second Edition
With contributions by
Kristi J. Smock and Robert C. Blaylock
Sterling T. Bennett, MD, MS George M. Rodgers, MD, PhD
Intermountain Healthcare University of Utah Health Sciences
Murray, UT Ctr. Department of Hematology
USA Salt Lake City, UT
USA
Christopher M. Lehman, MD
University of Utah Health Sciences
Ctr. Department of Pathology
Salt Lake City, UT
USA
ISBN 978-3-319-08923-2 ISBN 978-3-319-08924-9 (eBook)
DOI 10.1007/978-3-319-08924-9
Springer Cham Heidelberg New York Dordrecht London
Library of Congress Control Number: 2014951714
© Springer International Publishing Switzerland 2015
T his work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of
the material is concerned, specifi cally the rights of translation, reprinting, reuse of illustrations, recitation,
broadcasting, reproduction on microfi lms or in any other physical way, and transmission or information
storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology
now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection
with reviews or scholarly analysis or material supplied specifi cally for the purpose of being entered and
executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this
publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher's
location, in its current version, and permission for use must always be obtained from Springer.
Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations
are liable to prosecution under the respective Copyright Law.
T he use of general descriptive names, registered names, trademarks, service marks, etc. in this publication
does not imply, even in the absence of a specifi c statement, that such names are exempt from the relevant
protective laws and regulations and therefore free for general use.
While the advice and information in this book are believed to be true and accurate at the date of
publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for
any errors or omissions that may be made. The publisher makes no warranty, express or implied, with
respect to the material contained herein.
Printed on acid-free paper
Springer is part of Springer Science+Business Media (www.springer.com)
Pref ace
I n the course of our practice as coagulation laboratory directors, we have acquired
personal libraries of hemostasis and thrombosis texts that serve as excellent refer-
ences for the basic science and clinical aspects of hemostasis. What was missing,
though, was a single reference text that provided practical information and guidance
on the topics relevant to directing a coagulation laboratory. After talking about it for
several years, we attempted to fi ll the void with the fi rst edition of a handbook con-
taining the information we provide to the residents and fellows that we are helping
train to become laboratory directors. We have now updated the information in our
handbook to account for changes in the coagulation laboratory and transfusion med-
icine practice that have occurred since the initial edition was published.
In revising this book, we have tried to cite the consensus recommendations of
authoritative bodies whenever possible and, otherwise, have cited reviews, chapters,
and research articles of experts in their respective fi elds. These references should act
as a starting point for a more detailed study of the various aspects of coagulation
testing.
I t is our intent that pathologists, clinical laboratory scientists, and other physi-
cians serving as laboratory directors fi nd this new edition of the book helpful in
understanding and carrying out their responsibilities. We also hope that coagulation
laboratory supervisors, technologists, and technicians fi nd this to be a helpful refer-
ence for the day-to-day operation of the laboratory. Finally, we hope that residents
and fellows fi nd this book to be a useful tool for learning the basics of coagulation
testing and for studying for board examinations.
Salt Lake City, UT, USA Sterling T. Bennett
Christopher M. Lehman
George M. Rodgers
v

Contents
1 Role and Responsibilities of the Laboratory Director . . . . . . . . . . . . . 1
1.1 General Responsibilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Personnel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.3 Facilities and Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
1.4 Test Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
1.5 Quality Management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.6 Consultation and Education . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
1.7 Communication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
1.8 Operational Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
1.9 Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.10 Common Pitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.11 Summary and Key Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2 Collection of Coagulation Specimens. . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.1 Collection of Specimens for Hemostasis Testing . . . . . . . . . . . . . . 19
2.2 Citrate Anticoagulant Concentration. . . . . . . . . . . . . . . . . . . . . . . . 19
2.3 Plastic vs. Glass Tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.4 Collection Techniques. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.5 Specimen Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2.6 Specimen Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2.7 Problem Detection and Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2.8 Coagulation Testing on Specimens Other than Citrated Plasma. . . 30
2.9 Common Pitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
2.10 Summary and Key Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3 Instrumentation for the Coagulation Laboratory. . . . . . . . . . . . . . . . . 33
3.1 Laboratory Instruments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.1.1 Test Methodologies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.1.2 Detection Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3.2 Point of Care Instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
3.2.1 Waived PT/INR Instruments. . . . . . . . . . . . . . . . . . . . . . . . 35
vii
viii Contents
3.2.2 POC Analyzers Designed for Coagulation
Monitoring During Invasive Procedures. . . . . . . . . . . . . . . 36
3.2.3 Viscoelastic Analyzers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.2.4 Platelet Function Analyzers . . . . . . . . . . . . . . . . . . . . . . . . 39
3.3 Platelet Aggregometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.3.1 Light Transmission Aggregometers (LTA). . . . . . . . . . . . . 40
3.3.2 Multiplate® Analyzer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.3.3 PFA-100®. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.3.4 Plateletworks®. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
3.3.5 VerifyNow™. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
3.4 Summary and Key Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
4 Validation of Hemostasis Assays, Analyzers, and Reagents. . . . . . . . . 45
4.1 Validation Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
4.2 Validation Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
4.3 Validation Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
4.4 Validation Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
4.5 Analyzer Set-up and Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
4.6 Calibration and Calibration Verifi cation. . . . . . . . . . . . . . . . . . . . . 47
4.7 Quality Control Ranges. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.8 Reference Intervals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
4.9 Performance Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4.10 Method Comparisons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
4.11 INR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
4.12 Heparin Therapeutic Ranges. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
4.13 Instrument Interfaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
4.14 Reports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
4.15 Implementation Readiness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
4.16 Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
4.17 “Full” Versus “Partial” Validations. . . . . . . . . . . . . . . . . . . . . . . . . 65
4.18 Other Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
4.19 Common Pitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
4.20 Summary and Key Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
5 Hemostasis Screening Assays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
5.1 Hemostasis Screening Assays: Use and Interpretation. . . . . . . . . . 69
5.2 The CBC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
5.3 The PT Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
5.4 The PTT Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
5.5 The Mixing Test (Inhibitor Screen). . . . . . . . . . . . . . . . . . . . . . . . . 74
5.6 The Thrombin Time Assay. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
5.7 Fibrinogen Assays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
5.8 D-dimer Assays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
5.9 The Bleeding Time (BT) Test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Contents ix
5.10 Interpretation of Hemostasis Screening Tests in Patients
with Bleeding Disorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
5.11 Key Points. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
6 Testing for Inherited Bleeding Disorders. . . . . . . . . . . . . . . . . . . . . . . . 83
6.1 Qualitative Platelet Disorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
6.2 Platelet Aggregation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
6.3 von Willebrand’s Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
6.4 Assays for vWF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
6.5 vWF Immunoassay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
6.6 Ristocetin Cofactor Activity (vWF Activity) Assay. . . . . . . . . . . . 89
6.7 Factor VIII Activity Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
6.8 vWF Multimeric Analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
6.9 A ppropriate Test Ordering for Platelet-Type Bleeding Disorders. . . 91
6.10 The Platelet Function Analyzer (PFA)-100®. . . . . . . . . . . . . . . . . . 92
6.11 Inherited Coagulation Disorders. . . . . . . . . . . . . . . . . . . . . . . . . . . 92
6.12 Factor XIII (Clot Stability) Assay. . . . . . . . . . . . . . . . . . . . . . . . . . 93
6.13 Fibrinogen Activity Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
6.14 A lpha-Antiplasmin Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
2
6.15 Assays for Factor VIII Antibodies (Inhibitor Assays) . . . . . . . . . . 95
6.16 Key Points. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
7 Testing for Acquired Platelet Disorders. . . . . . . . . . . . . . . . . . . . . . . . . 99
7.1 Platelet Counting Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
7.1.1 Reference Method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
7.1.2 Automated Platelet Counters. . . . . . . . . . . . . . . . . . . . . . . . 100
7.2 Platelet Antibody Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
7.2.1 Immune-Mediated Thrombocytopenia . . . . . . . . . . . . . . . . 101
7.2.2 HLA Antibody Tests. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
7.2.3 Platelet Antibody Tests. . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
7.2.4 Testing for Heparin-Dependent Antibodies . . . . . . . . . . . . 103
7.2.5 Clinical Utility of Platelet Antibody Tests . . . . . . . . . . . . . 104
7.3 Platelet Function Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
7.3.1 Myeloproliferative Disorders . . . . . . . . . . . . . . . . . . . . . . . 105
7.3.2 Uremia. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
7.3.3 Antiplatelet Drugs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
7.3.4 Cardiovascular Surgery. . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
7.4 Summary and Key Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
8 Acquired Coagulation Disorders and TTP . . . . . . . . . . . . . . . . . . . . . . 111
8.1 Liver Disease and Vitamin K Defi ciency . . . . . . . . . . . . . . . . . . . . 111
8.2 DIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
8.3 Antibodies to Coagulation Factors . . . . . . . . . . . . . . . . . . . . . . . . . 112