Dalteparin versus Enoxaparin for the prevention of venous thromboembolic events in trauma patients.

Abstract

The use of low-molecular-weight heparin (LMWH) for the chemoprophylaxis of venous thromboembolism (VTE) in trauma patients is supported by Level-1 evidence. Because Enoxaparin was the agent used in the majority of studies for establishing the efficacy of LMWH in VTE, it remains unclear if Dalteparin provides an equivalent effect. To compare Dalteparin to Enoxaparin and investigate their equivalence as VTE prophylaxis in trauma. Trauma patients receiving VTE chemoprophylaxis in the Surgical Intensive Care Unit of a Level-1 Trauma Center from 2009 (Enoxaparin) to 2010 (Dalteparin) were included. The primary outcome was the incidence of clinically significant VTE. Secondary outcomes included heparin-induced thrombocytopenia (HIT), major bleeding, and drug acquisition cost savings. Equivalence margins were set between -5 and 5%. A total of 610 patient records (277 Enoxaparin, 333 Dalteparin) were reviewed. The two study groups did not differ significantly: blunt trauma 67 vs. 62%, p=0.27; mean Injury Severity Score (ISS) 17±10 vs. 16±10, p=0.34; Acute Physiology and Chronic Health Evaluation (APACHE) II score 17±9 vs. 17±10, p=0.76; time to first dose of LMWH 69±98 vs. 65±67h, p=0.57). The rates of deep venous thrombosis (DVT) (3.2 vs. 3.3%, p=1.00), pulmonary emboli (PE) (1.8 vs. 1.2%, p=0.74), and overall VTE (5.1 vs. 4.5%, p=0.85) did not differ. The absolute difference in the incidence of overall VTE was 0.5% [95% confidence interval (CI): -2.9, 4.0%, p=0.85]. The 95% CI was within the predefined equivalence margins. There were no significant differences in the frequency of HIT or major bleeding. The total year-on-year cost savings, achieved with 277 patients during the switch to Dalteparin, was estimated to be $107,778. Dalteparin is equivalent to Enoxaparin in terms of VTE in trauma patients and can be safely used in this population, with no increase in complications and significant cost savings.