Low-molecular-weight heparin for the prevention of postoperative venous thromboembolism after abdominal surgery: a review

Purpose of review To analyze the effect of low-molecular-weight heparin in abdominal surgery, which carries a significant fisk of thrombosis, a risk further increased by cancer. Recent findings Searches in EMBASE and PubMed between 1980 and 2004 were conducted to identify studies of thromboprophylax is in abdominal surgery patients. Sixteen comparative studies were identified. They showed that low-molecular-weight heparin is as effective as unfractionated heparin in reducing venous thromboembolism and, at appropriate doses, can reduce bleeding complications. In very-high-risk cancer patients, a higher dose of low-molecular-weigh heparin may offer increased efficacy without increasing the risk of bleeding. Extending the standard 7-10-day low-molecular-weight heparin prophylaxis period may benefit certain high-risk patient groups. Summary Patients undergoing abdominal surgery should be stratified according to thromboembolism risk and given prophylaxis accordingly. Low-molecular-weight heparin is a recommended alternative to unfractionated heparin in moderate- or high-risk patients. In patients with cancer, high doses of low-molecular-weight heparin may offer increased efficacy without increased bleeding, and an extended 4-week period of prophylaxis could be beneficial.