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

PURPOSE: 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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.