Release Date: Aug 2017
MOC: PC, MK, PBL
Elizabeth Van Cott, MD
Director of Coagulation Laboratory, Medical Director of Core Laboratory
Massachusetts General Hospital, Boston, MA; Associate Professor, Harvard Medical School, Boston, MA
Several direct-acting oral anticoagulants (DOAC) have emerged in recent years and are now frequently used: in particular, apixaban, and rivaroxaban (direct factor Xa inhibitors) and dabigatran, a direct thrombin inhibitor. Thus, many patients can now be treated with apixaban, rivaroxaban or dabigatran instead of warfarin or heparin. Unlike warfarin and heparin, the new anticoagulants do not require routine laboratory monitoring, but if a medical situation arises with the need for monitoring, the INR or aPTT are not the most suitable tests. Unlike previous novel anticoagulants that have become available in recent years (such as argatroban, bivalirudin, or fondaparinux), apixaban, rivaroxaban and dabigatran can be taken orally and are appropriate for outpatients. Therefore, laboratories should be prepared to handle the impact of these anticoagulants so that their patients can be managed safely. This presentation will include practical facts about these anticoagulants, suggestions for how routine and specialized tests can (or cannot) be used to assess their levels, and demonstration of the numerous coagulation tests that cannot be performed (due to interference) while patients are taking one of these new anticoagulants. Participants will be able to answer frequently-asked questions about apixaban, rivaroxaban and dabigatran, including lab testing options, reversal (e.g., does dialysis or oral charcoal help?), cost, how soon after starting the anticoagulant does the anticoagulant level peak, how soon after discontinuation does the anticoagulation effect disappear, does liver or renal dysfunction prolong the half-life, and what concentration is therapeutic.
After attending this session, participants will be able to:
· Answer frequently-asked questions about apixaban, rivaroxaban and dabigatran, including lab testing options, reversal, cost, when to draw specimens (peak times), half-life, liver or renal dysfunction, therapeutic concentrations, etc.
· Understand how routine (PTT or PT) and specialized lab tests assess apixaban, rivaroxaban, or dabigatran levels.
· Recognize the many coagulation lab tests that give erroneous results when apixaban, rivaroxaban, or dabigatran are present in the specimen
Who should attend? Practicing Pathologists, Residents, Doctoral Scientists, Pathologists' Assistants, Bench Supervisors, Phlebotomists, Students