Deep vein thrombosis (DVT) and pulmonary embolism, or venous thromboembolism, are possible complications of surgery and trauma. These complications extend hospital stay and are associated with long-term disability and death. Patients undergoing total hip or knee replacement surgery or surgery for colorectal cancer are at high risk of venous thromboembolism. Sluggish venous blood flow, increased blood clotting and blood vessel endothelial injury are contributing factors. Treating more than one of these causes may improve prevention. Mechanical intermittent pneumatic leg compression reduces venous stasis while medications such as aspirin and anticoagulants such as low molecular weight heparin reduce blood clotting. The medications can also increase the risk of bleeding.
The present review showed that combining the two methods was more effective than a single preventative measure. Compared to compression alone, compression plus anticoagulant (combined prophylactic modalities) clearly decreased the incidence of both symptomatic pulmonary embolism (from 2.7% to 1.1%) and DVT (from 4% to 1.6%). Compared with medication with anticoagulants alone, combined compression and medication clearly reduced the incidence of DVT (from 4.21% to 0.65%). The effect on pulmonary embolism could not be determined because of the lack of events in the included
studies.
These conclusions are based on 11 controlled trials involving a total of 7431 surgery patients. The mean age of patients, where reported, was 65.5 years. Most patients had either a high-risk procedure or condition. The surgical procedures were orthopedic surgery in six trials and urological, cardiothoracic, general surgery and gynecology procedures in the other trials. The magnitude of the reduction in venous thromboembolism may be less for patients at moderate risk.
