Prophylaxis of postoperative deep vein thrombosis and pulmonary embolism

Routine prophylaxis of deep vein thrombosis and pulmonary embolism is justified by the importance of these complications as sources of major morbidity and mortality in otherwise healthy patients more than 40 years old undergoing extensive elective operations. As no one prophylactic technique is ideal, the continuing controversy is over the choice of technique for each patient. Appropriate selection of a prophylactic technique requires a careful preoperative assessment based upon the relative risk of thromboembolism due to associated disease, the risk of bleeding complications secondary to an underlying bleeding diathesis, the possibility of major morbidity from unexpected postoperative bleeding determined by the anatomic site of surgical procedure and the risk of thromboembolism imposed by the surgical procedure itself (57). For patients at high risk, warfarin remains the prophylactic agent of choice. To date, the available data on combinations of mechanical and chemical techniques are incomplete and contradictory, but future studies may identify synergistic combinations. In patients at high risk who also greatly risk having bleeding complications, vena caval interruption should be considered. In patients undergoing operation at moderate risk, low dose heparin, dextran and external pneumatic compression devices are beneficial. In patients undergoing elective hip and knee operation at moderate risk, aspirin appears especially safe and effective. When major morbidity may result from anticoagulation in patients at moderate risk for deep vein thrombosis and pulmonary embolism, external pneumatic compression devices, gradient elastic stockings or elevation of the leg should be used. Further carefully controlled clinical trials are needed to identify even better options for prophylaxis.