(1022) Increased Enoxaparin Dosing in Burn and Trauma Patients Reliably Reaches Target Prophylactic Levels

Introduction: Recent evidence suggests that enoxaparin dosed at 30 mg and 40 mg twice daily for non-obese and obese burn and trauma patients, respectively, may result in sub-optimal target thromboprophylactic plasma anti-Xa levels in up to 84% of patients and subsequently lead to a higher incidence of venous thromboembolism (VTE). Higher enoxaparin dosing regimens have been suggested; however, few studies have evaluated increased enoxaparin dosing protocols in these patient populations.

Methods: A retrospective chart review of an American Burn Association-verified burn and level 1 trauma center from June 2022 until July 2023 identified patients initiated on an intensive enoxaparin protocol for VTE prophylaxis. Per protocol, patients were initiated on enoxaparin 40 mg twice daily if < 100 kg or BMI < 30 kg/m2 or weight-based dosing at 0.5 mg/kg twice daily if >/=100kg or BMI >/= 30 kg/m2. Patients >65 years of age or weight < 50 kg were eligible for reduced dosing. Patients were included if they were at least 18 years of age, dosed according to protocol criteria, and received at least three sequential doses of enoxaparin with appropriately timed peak plasma anti-Xa levels to monitor efficacy. Patient demographics were analyzed, including body weight, body mass index, creatinine clearance and total body surface area (TBSA) burn.

Results: During the study period, 245 patients were screened with 200 patients included for analysis. Only 24.5% of the patients evaluated did not reach target peak plasma anti-Xa levels (0.2-0.5 IU/mL) on our protocol. Burn patients were more likely to achieve target anti-Xa levels per protocol compared to trauma (81.4% vs 64.8%, p=0.0105). An association between severe burns >20% TBSA and inability to meet anti-Xa goals was also noted.

Conclusions: Current utilization of a higher dose of twice daily enoxaparin for VTE prophylaxis has an improved likelihood of achieving plasma anti-Xa targets compared to standard dosing strategies. Utilization of this elevated dosing strategy targeting peak plasma anti-Xa levels to reduce VTE rates in the severe burn and trauma patient populations should be further evaluated.