Efficacy and Safety of Two Different Enoxaparin Doses for Thromboprophylaxis in Non-critically Ill Patients: A Randomized Controlled Trial.

Background: Recently, a few studies based on anti-factor Xa activity levels have propounded doubtful and sub-prophylactic levels by the usual dose of enoxaparin in surgical and critically ill patients. In this study, we assessed two doses of enoxaparin in adult non-critically ill patients. Methods: Patients were randomly assigned into two groups of intervention and control. While the intervention group received enoxaparin with a daily dose of 60 mg, the control group received enoxaparin 40 mg. Anti-factor Xa activity was measured based on the peak steady-state levels. The level of 0.2 to 0.4 IU/mL was considered as a prophylactic goal. All individuals were followed for bleeding or thromboembolic events during admission. Results: The mean levels of anti-factor Xa were 0.29 ± 0.13 IU/mL in the control group (n = 31) and 0.44 ± 0.19 IU/mL in the intervention group (n = 29). More patients in the control group had an optimal level of anti-factor Xa compared to the patients in the intervention group (62.1% vs. 29%). No adverse outcomes were detected in any of the groups. Conclusions: Enoxaparin dose of 60 mg daily provided anti-factor Xa level higher than desired in most patients. In non-critically ill patients, the dose of 40 mg is the proper dose for thromboprophylaxis.