(463) Comparison of Anticoagulation Reversal Strategies for Warfarin-Associated Gastrointestinal Bleeding

Introduction: Gastrointestinal bleeding (GIB) is a common complication associated with warfarin use. Despite this, the optimal strategy for anticoagulation reversal with fresh frozen plasma (FFP), vitamin K, or prothrombin complex concentrate (PCC) is not clear from current literature or society guidelines. This study aims to describe outcomes of these strategies in warfarin-associated GIB.

Methods: A retrospective analysis of emergency department (ED) patients with warfarin-associated GIB who presented to an academic medical center and associated community hospitals was performed, comparing reversal with PCC, FFP, vitamin K, or no reversal agent. Outcomes of interest included 30-day all-cause mortality and 30-day thrombotic events.

Results: Of 815 patients, within 12 hours of presentation, 10.7% received reversal with PCC (with or without vitamin K), 12.9% with FFP (with or without vitamin K), and 34.9% with vitamin K alone; 41.5% of patients received no reversal agent. There were significant between-group differences in baseline INR (3.8 PCC vs 4.0 FFP vs 3.8 vitamin K vs 2.7 no reversal, p< 0.001), baseline hemoglobin (7.9 vs 8.2 vs 8.8 vs 9.0, p=0.003), and anticoagulation for an indication of atrial fibrillation (77.0% vs 78.1% vs 78.2% vs 64.2%, p< 0.001). Compared to patients who received no reversal, those receiving PCC or FFP were more likely to have hemodynamic instability in the ED (64.4% vs 42.9% vs 33.7% vs 31.4%, p< 0.001) and receive packed red blood cells (83.9% vs 79.0% vs 60.4% vs 55.0%, p< 0.001). Compared to all other groups, patients receiving PCC had significantly higher 30-day mortality (18.4% vs 5.7% vs 4.6% vs 5.6%, p< 0.001), which remained significant after individually adjusting for hemodynamic instability and ICU admission. There were no significant differences in rates of any thrombotic event within 30 days (3.4% vs 3.8% vs 1.4% vs 1.2%, p=0.20).

Conclusions: Warfarin-associated GIB has a high mortality. In this cohort, patients who received PCC as a reversal strategy had a threefold increase in mortality compared to FFP, vitamin K alone, or no reversal, even after adjusting for severity of the bleeding. Further research is necessary to understand factors leading to this significant worse outcome in patients receiving PCCs for anticoagulation reversal.