In Search of Safe and Effective Oral Anticoagulation

There is a large gap between the need for anticoagulation and the use of drug therapy for this purpose in ambulatory care. Major lower-extremity orthopedic surgery such as total hip replacement and total knee replacement are associated with an increased risk of venous thromboembolism (VTE). Anticoagulant prophylaxis is necessary to reduce the risk of deep vein thrombosis (DVT), which may progress to symptomatic outcomes such as pulmonary embolism (PE). Prophylaxis and treatment of patients with symptomatic VTE occurs in 2 phases. Initial therapy focuses on rapid achievement of effective anticoagulation and usually involves subcutaneous low-molecular-weight heparin. Long-term prophylaxis with the vitamin K antagonist, warfarin, reduces the risk of recurrent VTE from about 27% (without prophylaxis or inadequate prophylaxis) to 4% during the first 3 months of observation.