Flexibility in administration of fondaparinux for prevention of symptomatic venous thromboembolism in orthopaedic surgery.

Venous thromboembolism (VTE) is a common complication of total joint arthroplasty. Fondaparinux VTE prophylaxis is currently begun 6 to 8 hours after surgery. Flexible dosing may reduce bleeding risk and allow easier use by starting the morning after surgery instead of staggered hours on the surgery day. This study examined flexible timing of the first dose of fondaparinux. Whether the first dose was administered 8 +/- 2 hours after surgery or the morning after surgery, no significant difference was observed in incidence of symptomatic VTE (2.0% and 1.9%, respectively, P = .89). Major and minor bleeding events were similar between groups (1.2% and 0.7% [P = .19], and 1.4% and 2.0% [P = .31], respectively). Delaying initiation of fondaparinux prophylaxis provides an option after total joint arthroplasty with preserved efficacy and safety.