Management and Outcomes of Bleeding Events in Patients in the Emergency Department Taking Warfarin or a Non–Vitamin K Antagonist Oral Anticoagulant

Background Most comparisons of bleeding patients who are taking warfarin or a non–vitamin K oral anticoagulant (NOAC) have been limited to admitted patients and major bleeding events in well-controlled, clinical trial settings. Objectives We describe the clinical characteristics, interventions, and outcomes in patients who are taking warfarin or a NOAC who presented to the emergency department (ED) with any bleeding event. Methods We conducted a structured, retrospective, observational study of nonvalvular atrial fibrillation, pulmonary embolism, or deep vein thrombosis warfarin- or NOAC-treated patients presenting with any bleeding event to a large, academic ED between January 2012 and March 2015. We used descriptive statistics to summarize baseline characteristics, treatments, and outcomes and performed subgroup analyses based on the type of anticoagulant and site of bleeding. Results The electronic search yielded 95 cases of patients taking a NOAC (i.e., dabigatran [33], rivaroxaban [32], or abixaban [30]) and 342 patients taking warfarin. Reversal agents were rarely used in all anticoagulant groups. Case fatality rates were similar among warfarin- and NOAC-treated patients for gastrointestinal bleeding (7% vs. 7%) and intracranial hemorrhage (18% vs. 4%), respectively. After adjustment for other factors, only intracranial hemorrhage (odds ratio 4.4; 95% confidence interval 1.4–13.3) was associated with mortality. Conclusions Despite the rare use of reversal strategies, mortality was low and outcomes were comparable among patients with bleeding events presenting to the ED while taking a NOAC compared with warfarin.