Perioperative management of patients on chronic antithrombotic therapy.

Perioperative management of antithrombotic therapy is a situation that occurs frequently and requires consideration of the patient, the procedure, and an expanding array of anticoagulant and antiplatelet agents. Preoperative assessment must address each patient's risk for thromboembolic events balanced against the risk for perioperative bleeding. Procedures can be separated into those with a low bleeding risk, which generally do not require complete reversal of the antithrombotic therapy, and those associated with an intermediate or high bleeding risk. For patients who are receiving warfarin who need interruption of the anticoagulant, consideration must be given to whether simply withholding the anticoagulant is the optimal approach or whether a perioperative "bridge" with an alternative agent, typically a low-molecular-weight heparin, should be used. The new oral anticoagulants dabigatran and rivaroxaban have shorter effective half-lives, but they introduce other concerns for perioperative management, including prolonged drug effect in patients with renal insufficiency, limited experience with clinical laboratory testing to confirm lack of residual anticoagulant effect, and lack of a reversal agent. Antiplatelet agents must also be considered in the perioperative setting, with particular consideration given to the potential risk for thrombotic complications in patients with coronary artery stents who have antiplatelet therapy withheld.