Deep vein thrombosis prophylaxis in the outpatient setting: preventing complications following hospital discharge.

Venous thromboembolism is an important complication in patients undergoing major orthopedic surgery. Without prophylaxis, there is a 50% to 60% incidence of deep vein thrombosis (DVT), a 10% to 30% incidence of proximal vein thrombosis, and a 1% to 2% rate of fatal pulmonary embolism after total hip replacement. The incidence of DVT after knee arthroplasty is even higher, ranging from 55% to 70% and, although there are no accurate figures on the incidence of fatal pulmonary embolism, it is likely to be similar to that following hip arthroplasty. Low molecular weight heparins (LMWHs) have been shown to be effective and safe in the prevention of venous thromboembolism in patients undergoing major orthopedic procedures. In comparative studies, LMWHs are more effective than adjusted dose heparin or warfarin without increased risk of bleeding.