Effectiveness and safety of bemiparin versus low-molecular weight heparins in orthopaedic surgery

Objective: To evaluate the effectiveness and safety of bemiparin in the prophylaxis of thromboembolism in orthopaedic surgery with respect to other low-molecular-weight heparins. Methods: A meta-analysis of effectiveness and safety of low-molecular weight heparins versus standard heparin in orthopaedic surgery was performed. A literature search was done of Medline and Excerpta Medica from 1988 to 1998. Only controlled clinical trials were selected for meta-analysis. Differences between groups were expressed as odds ratios and these were combined by the Mantel-Haenszel method. Main outcome measures: Rates of deep vein thrombosis, pulmonary embolism and wound haematoma. Results: Twenty-one studies involving 4605 patients were included in the meta-analysis. Bemiparin significantly reduces the rates of deep vein thrombosis (OR; 95% CI = 0.38, 0.15-0.90). No significant differences were found in pulmonary embolism and wound haematoma. The incidence of deep vein thrombosis is also lower with enoxaparin than with unfractionated heparin. However, only nadroparin reduced the incidence of pulmonary embolism (ORs = 0.24, 95% CI = 0.05-0.94). In any case, the incidence of wound haematoma was not significant. Conclusion: Bemiparin seems to be as effective and safe as the other low-molecular-weight heparins in the prevention of thromboembolic complications in orthopaedic surgery.