Prophylaxis of deep venous thrombosis in total hip arthroplasty

Deep venous thrombosis is one of the most common perioperative complication s after total hip arthroplasty. Systemic anticoagulation has been the gold standard for prophylaxis of postoperative deep venous thrombosis. There is no doubt that early mobilization and the use of pneumatic compression devic es decrease the overall deep venous thrombosis rate. Single postoperative p rophylaxis may decrease the overall deep venous thrombosis rate to 15-20% a nd the proximal deep venous thrombosis rate to approximately 7%. However,the activation of thrombogenesis is mainly an intraoperative event. The position of the extremity during the implantation of the femoral compo nent leads to obstruction of the venous outflow. At the same time,the coagu lation cascade is activated and markers of thrombogenesis in the blood are increased. By combining intraoperative (hypotensive epidural anesthesia and intraopera tive heparin) and postoperative (pneumatic compression devices and aspirin) prophylaxis of deep venous thrombosis,the total deep venous thrombosis rat e is reduced to less than 10% and the proximal deep venous thrombosis rate is reduced to 2%. Patients with increased risk for deep venous thrombosis s hould receive Coumadin or low-molecular weight heparin. In addition, hypote nsive epidural anesthesia reduces the intraoperative blood loss and the nee d for postoperative blood transfusion.