Evaluation of the effectiveness and safety of bemiparin in a large population of orthopedic patients in a normal clinical practice

Abstract

The authors conducted a prospective, open, multicenter, observational study to audit the utilization patterns of bemiparin in orthopedic patients in daily clinical practice. They analyzed rates of documented symptomatic venous thromboembolism (VTE) (deep vein thrombosis and pulmonary embolism) confirmed by objective methods, major bleeding, death, thrombocytopenia, and other adverse events. It was also intended to analyze the influence of concomitant factors (bemiparin dose, concomitant medications, age, and obesity) on VTE and bleeding rates. A total of 7959 patients were included and received bemiparin for 28 days (median). Bemiparin 3500 IU/d was used in 84.9% of patients, whereas bemiparin 2500 IU/d was administered to 15.1% of patients. Reason for prophylaxis (number of cases [%]) included cast immobilization of the leg (2052 [25.8%]), knee replacement (1082 [13.6%]), hip replacement (876 [11.0%]), hip fracture surgery (437 [5.5%]), other lower limb surgery (1569 [19.7%]), knee arthroscopy (769 [9.7%]), and spine surgery (231 [2.9%]). A total of 943 patients with insufficient data on reason for prophylaxis and 560 patients with no outcome assessment were excluded from the analysis of clinical outcomes. Among 6456 assessable patients, the authors found a low rate of documented symptomatic VTE (0.91%), major bleeding (0.17%), deaths (0.37%), and mild to moderate thrombocytopenia (0.51%). None of the major bleedings was fatal or occurred in a critical organ. There were 3 deaths in which fatal pulmonary embolism (PE) could not be ruled out. There were no cases of severe type-II thrombocytopenia. VTE rates were not increased in obese patients, and major bleeding rates were not increased in elderly patients or in patients taking nonsteroidal anti-inflammatory drugs. In conclusion, bemiparin prophylaxis, given for 3 to 4 weeks in cast immobilization of the leg and other orthopedic procedures, was associated with low rates of VTE, bleeding, and other adverse events in normal clinical practice.