Semin Thromb Hemost 2017; 43(03): 253-260
DOI: 10.1055/s-0036-1581128
Review Article
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Activated Partial Thromboplastin Time Monitoring of Unfractionated Heparin Therapy: Issues and Recommendations

Richard A. Marlar
1  Pathology and Laboratory Medicine Service, Oklahoma City VA Health Care System, Oklahoma City, Oklahoma
2  Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
,
Bernadette Clement
3  College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
,
Jana Gausman
1  Pathology and Laboratory Medicine Service, Oklahoma City VA Health Care System, Oklahoma City, Oklahoma
› Author Affiliations
Further Information

Publication History

Publication Date:
06 June 2016 (online)

Abstract

When administering unfractionated heparin (UFH), therapeutic levels of anticoagulation must be achieved rapidly and maintained consistently in the therapeutic range. The basic assays for monitoring UFH therapy are the activated partial thromboplastin time (APTT) and/or the chromogenic antifactor Xa or antithrombin assays. For many laboratories, the APTT is the preferred standard of practice; however, the APTT is a surrogate marker that only estimates the heparin concentration. Many factors, including patient variation, reagents of the APTT, UFH composition, and concentration can influence the APTT result. This article reviews various methods to determine the heparin therapeutic range and presents recommendations for the laboratory to establish an APTT heparin therapeutic range for all sizes of hospitals.