Introduction: Factor Xa (fXa) inhibitor reversal for life-threatening bleeding is controversial due to a lack of high-quality evidence. The purpose of this study was to determine the hemostatic efficacy of four-factor prothrombin complex concentrate (4F-PCC) for the reversal of fXa inhibitors compared to warfarin for life-threatening bleeding.

Methods: This was a multicenter, retrospective cohort study at two academic medical centers between January 1, 2014–December 31, 2019, which included patients who presented to the emergency department with a life-threatening bleed necessitating anticoagulation reversal with 4F-PCC. The primary endpoint was achievement of hemostatic efficacy after 4F-PCC administration.

Results: Of the 525 patients who had an order for 4F-PCC during the study period, 148 patients met the criteria for inclusion (n = 48 fXa inhibitor group; n = 100 warfarin group). Apixaban (52.1%) and rivaroxaban (45.8%) were the most commonly used fXa inhibitors. Effective hemostasis was similar between groups (79.2% fXa inhibitor group vs 85% warfarin group, p = 0.38). This was consistent across all types of bleeding. Thrombotic events were rare in both groups (2% vs 3%). 

Conclusion: This multicenter, retrospective cohort study demonstrated that using 4F-PCC for treatment of life-threatening bleeding produced effective hemostasis in patients on fXa inhibitors and warfarin.