Evidence based venous thromboprophylaxis in patients undergoing total hip replacement (THR), total knee replacement (TKR) and hip fracture surgery (HFS)

Patients undergoing total hip, knee replacement and hip fracture surgery are at high risk of developing venous thromboembolism. Incidence of deep vein thrombosis ranges from 40% to 70% and 1% to 7% for fatal pulmonary embolism. Venous thromboprophylaxis comprises mechanical and pharmacological intervention but for added protection in major orthopaedic surgery, most national and international guidelines advise a combined regimen of both modalities. Reportedly, 40% of such patients do not receive pharmacological prophylaxis because of the increased risk of bleeding. When considering pharmacological prophylaxis, a trade off between the benefits of reducing venous thromboembolism and the potential harms of bleeding and haematoma formation must be balanced. Anti-embolism stockings, intermittent pneumatic pump and foot impulse devices are the main mechanical methods but are often collectively addressed as mechanical prophylaxis as no difference in efficacy exists between these devices. The National Institute for Health and Clinical Excellence advises that one of those devices be commenced preoperatively and continued until the patients have no significant reduced immobility. Anti-embolism stockings (knee or thigh) are to be applied with caution. Mechanical prophylaxis is particularly important in hip/knee and hip fracture surgery, when patients are not protected by pharmacological prophylaxis. Unfractionated heparin, low molecular weight heparin, pentasaccharide fondaparinux and old and new oral anticoagulants are the mainstay of pharmacological prophylaxis. In the absence of contraindication, it is recommended that pharma-cological prophylaxis is timely initiated postoperatively. Extended pharmacological prophylaxis is recommended for 28-35 days for hip replacement and hip fracture surgery and 10-14 days for knee replacement surgery. (C) 2011 Elsevier Ltd. All rights reserved.