Direct Oral Anticoagulants vs Low-Molecular-Weight Heparin for Thromboprophylaxis in Nonoperative Pelvic Fractures

Abstract

Background: Patients with pelvic fractures are prone to venous thromboembolic (VTE) complications. Recent literature shows superiority of direct oral anticoagulants (DOACs) over low-molecular-weight heparin (LMWH) for thromboprophylaxis in patients undergoing orthopaedic operations. The aim of our study was to compare in-hospital outcomes for DOACs vs LMWH in patients with nonoperative pelvic fractures.

Study design: We performed a 2-year (2015 to 2016) analysis of the American College of Surgeons-Trauma Quality Improvement Program (ACS-TQIP) database. We included all adult patients with isolated blunt pelvic fractures who were managed nonoperatively and received thromboprophylaxis with either LMWH or DOACs (Factor-Xa inhibitor or direct thrombin inhibitor). Patients were divided into 2 groups based on receipt of DOACs vs LMWH and were propensity-score-matched in a 1:2 ratio to control for possible confounding factors. Primary outcomes were deep venous thrombosis (DVT) and/or pulmonary embolism (PE). Secondary outcomes were pRBC transfusions, intervention for hemorrhage control, and in-hospital mortality after initiation of thromboprophylaxis.

Results: We identified 20,692 patients with pelvic fractures. There were 7,312 patients with isolated pelvic fractures included, 852 of whom were matched (DOACs: 284; LMWH: 568). Mean age was 43.2 ± 15 years, median Injury Severity Score was 14 (range 10 to 18). Matched groups were similar in demographics, vital signs, injury parameters, and timing of initiation of thromboprophylaxis. Overall, 5.2% of patients had DVT, 1.4% PE, and 1.3% died. Patients who received DOACs were less likely to develop DVT (1.8% vs 6.9%, p < 0.01) compared with LMWH. There was no difference in PE (p = 0.85) or in-hospital mortality (p = 0.79) between the 2 groups. Similarly, there was no difference in post-prophylaxis blood transfusion, and post-prophylaxis intervention for hemorrhage control.

Conclusions: In patients with nonoperative pelvic fractures, DOACs were associated with a reduced rate of DVT vs LMWH without increasing the risk of bleeding complications. No association was found between the type of thromboprophylactic agent and rates of PE or in-hospital mortality.