Anticoagulant or antiplatelet drugs and anesthesia
Yamamoto, K.
Masui. Japanese Journal of Anesthesiology 59(9): 1160-1165
2010
ISSN/ISBN: 0021-4892 PMID: 20857675 Document Number: 643776
An increasing number of preoperative patients are receiving therapy with an oral anticoagulant (warfarin) or antiplatelet drugs to prevent thromboembolic complications. Because of its irreversible inhibition on hepatic synthesis of vitamin K-dependent coagulation factors, warfarin must be stopped 3 to 4 (ideally 4 to 5) days prior to the planned major operation. Normal PT-INR is mandatory prior for neuraxial block. Rapid reversal of warfarin in emergency settings with FFP rather than vitamin K is advocated. More reliable and prompt reversal is possible with PCCs and rFVIIa, but this approach is off-label use in Japan as well as in the US. Antiplatelet drugs have different mechanisms to suppress platelet aggregation. Ticlopidine and clopidogrel should be stopped 7 days prior to the major surgery because of their irreversible inhibition on ADP receptors of platelets. Although it is recommended to stop aspirin 7 days prior to the planned major surgery in some guidelines, low dose oral aspirin (75-300 mg day(-1)) alone is accepted in another guideline because it does not create a level of risk that will interfere with the performance of neuraxial blocks.