RSS Feeds
Diagnostic Decision
Diagnostic Uses of the Activated Partial Thromboplastin Time and Prothrombin Time
Abstract
The activated partial thromboplastin time (APTT) and prothrombin time (PT) have three principal uses. In screening for coagulation disorders (or increased risk of postoperative hemorrhage), the tests add no information to the preoperative care of patients without clinical findings indicative of increased bleeding risk. Furthermore, the prevalence of asymptomatic congenital coagulopathies is so low that false-positive test results greatly outnumber true-positive results. Thus, clinicians may use clinical assessment to screen and should reserve coagulation tests to investigate patients with abnormal findings. In evaluating abnormal bleeding, these tests are sufficiently sensitive that if both are negative, further investigation of the coagulation system is obviated. If one or both tests are positive, the pattern of results directs further attention to limited segments of the coagulation sequence. In monitoring anticoagulation therapy, the APTT and PT tests appear to contribute to the safety and effectiveness of heparin and warfarin therapies, respectively.
Article and Author Information
-
▸From the Department of Medicine, University of Rochester, Highland and Strong Memorial Hospitals; Rochester, New York.
-
▸This paper was commissioned by the Blue Cross-Blue Shield Medical Necessity Project, under auspices of the Society for Research and Education in Primary Care Internal Medicine (SREPCIM), and is the sixth in a series being published in the Diagnosis and Treatment section. Harold C. Sox, Jr., M.D., is the editor for the series, and these papers are also being reviewed by John M. Eisenberg, M.D., and Sankey V. Williams, M.D., our consultants for Diagnostic Decision papers, as well as by selected manuscript consultants. This series will be published in a collective reprint, the availability of which will be announced later.—The Editor.
-
Grant support: By the Blue Cross/Blue Shield Association Medical Necessity Program in cooperation with the Technology Assessment Committee of the Society for Research and Education in Primary Care Internal Medicine (SREPCIM). Part of this work was done while Dr. Suchman was a Henry J. Kaiser Family Foundation Fellow in General Internal Medicne.
-
▸Requests for reprints should be addressed to Anthony L. Suchman, M.D.; Department of Medicine, Highland Hospital, South Avenue at Bellevue Drive; Rochester, NY 14620.
- © 1986 American College of Physicians
