Preoperative Versus Postoperative Initiation of Warfarin Therapy in Patients Undergoing Total Hip and Knee Arthroplasty

Abstract

The optimal strategy for postoperative deep venous thrombosis prophylaxis remains controversial in hip and knee arthroplasty. Warfarin causes transient hypercoagulability; however, the optimal timing of treatment remains unclear. We evaluated the effects of preoperative versus postoperative warfarin therapy with a primary endpoint of perioperative change in hemoglobin. Warfarin was dosed according to a standard nomogram. No difference in perioperative hemoglobin change was observed. The preoperative group demonstrated higher INRs. Initiation of warfarin preoperatively was not associated with any difference in perioperative hemoglobin change. Larger studies are needed to determine whether the risk of adverse events is increased with either strategy.

Keywords: Anticoagulation; Dosing regimen; Perioperative blood loss; Warfarin.