Weight based dosing of prophylactic enoxaparin was not associated with reduced venous thromboembolism events following open reduction and internal fixation of acetabular fractures.

Abstract

To compare venous thromboembolism (VTE) events in patients undergoing open reduction and internal fixation (ORIF) of acetabular fractures who did and did not receive weight-based dosing of prophylactic enoxaparin. This retrospective cohort study included patients with acetabular fractures treated with ORIF between 2013 and 2020 at a single level-1 trauma center. Patients with pre-existing VTE, allergy, no enoxaparin use, or receipt of other prophylactic agents were excluded. Patients were categorized as having received appropriate or inappropriate weight-based enoxaparin dosing based on institutional BMI-tiered protocol. The primary outcome was incidence of VTE, including deep vein thrombosis (DVT) and pulmonary embolism (PE). Group comparisons were performed with Pearson's Chi-square, and binomial logistic regression was used to adjust for additional VTE risk factors. Among 363 patients, 198 (54.5%) received appropriate weight-based dosing and 165 (45.5%) did not. Overall, 20 patients (5.5%) developed VTE (4 PE, 11 DVT, 3 both PE and DVT). Of these, 13 had received appropriate dosing. VTE incidence did not differ significantly between groups (6.6% vs. 4.2%, p = 0.334). Rates of isolated PE, isolated DVT, and combined events were also not significantly different (all p > 0.05). Logistic regression confirmed no significant association between weight-based dosing and VTE when adjusting for patient and clinical risk factors. Only half of patients with operative acetabular fractures received appropriate weight-based dosing of enoxaparin. Weight-based dosing was not associated with reduced VTE incidence, suggesting that receipt of prophylaxis itself may be the most important factor. Larger studies are warranted to verify these findings.