Post-operative thromboprophylaxis: new oral thrombin and factor X inhibitors and their place in clinical practice.

Thromboprophylaxis can reduce the incidence of postoperative thromboembolic events by two-thirds. Traditionally, unfractionated heparin, low-molecular-weight heparins, vitamin K antagonists, and mechanical methods have been used. Recently, thrombin and factor Xa (FXa) antagonists have been introduced in clinical practice. Advantages are oral administration, potentially higher efficacy in reducing thromboembolic events without increasing major bleeding, and no need for monitoring of the anticoagulatory effect. So far these drugs have mainly been tested after total hip and knee arthroplasties. However, data after most other orthopedic and surgical procedures are sparse. In special populations - for example, patients with renal failure - these drugs have not been sufficiently tested yet. Accordingly, the clinical use of these promising new drugs should be restricted to situations where efficacy has been proven with clear evidence from controlled clinical trials.