Transfusion and mortality after major trauma in patients on direct oral anticoagulants: a multicentre cohort study

BACKGROUND: Major trauma in patients with direct oral anticoagulants (DOACs) is increasing as treatment with DOACs is becoming more prevalent. DOACs add complexity to trauma due to increased risk of bleeding. The primary aim of this study was to compare the likelihood of packed red blood cell (PRBC) transfusion and PRBC volumes in patients with DOACs to non-anticoagulated controls after major trauma. Secondary aims were to compare mortality rates between these groups. METHODS: This was a multicentre retrospective cohort study with four participating hospitals. Inclusion criteria were age ≥ 18 years and admission for trauma with New Injury Severity Score (NISS) > 15 from Jan 1, 2019, to Dec 31, 2023. The Swedish Trauma Registry and medical records were used to identify patients and to retrieve data. For primary weighted analyses, propensity scores for DOACs were estimated using sex, age, injury mechanism, ASA class, antiplatelet treatment, and NISS. Non-weighted adjusted regression models were used for complementary analyses. RESULTS: A total of 1817 patients were admitted for major trauma during the study period, of which 756 patients were included in the analytic cohort. PRBC was administered to 30.8% of patients with DOACs and to 20.7% of controls. PRBC likelihood was higher among patients with DOACs (OR 1.73, 95% CI 1.03-2.91). The number of PRBC units among patients who received transfusions was not significantly higher for DOACs (GMR 1.11, 95% CI 0.79-1.56). Mortality rates within 24 h and 30 days did not differ significantly in primary analyses (OR 1.82, 95% CI 0.78-4.23 and OR 1.34, 95% CI 0.80-2.24, respectively). CONCLUSIONS: Patients with DOACs were more likely to receive PRBC transfusion, but PRBC volumes were not significantly different among transfused patients. Mortality did not differ significantly in the primary weighted analyses.