College of American Pathologists Conference XXXI on laboratory monitoring of anticoagulant therapy: laboratory monitoring of unfractionated heparin therapy.

OBJECTIVE: To review the state of the art as reflected in the medical literature and the consensus opinion of recognized experts in the field regarding the laboratory monitoring of unfractionated heparin therapy. DATA SOURCES, EXTRACTION AND SYNTHESIS: The authors made an extensive review of the literature. The draft manuscript was circulated to every participant in the consensus conference prior to the convening of the conference. Extensive discussion concerning all of the issues addressed in the manuscript as well as the resulting recommendations occurred. This information was then used to revise the manuscript into its final form.
CONCLUSIONS: The resulting manuscript has 23 specific recommendations regarding preanalytic, analytic, and postanalytic phases of monitoring and testing for complications related to unfractionated heparin therapy. This report contains detailed discussion of these recommendations and includes literature citations that support them. A number of issues for which consensus could not be reached are also discussed. A method is provided to assist laboratories, particularly small laboratories, in providing clinicians with an appropriate therapeutic range for the activated partial thromboplastin time, the most commonly used test in monitoring heparin therapy.