Coagulopathy due to warfarin in patients with major bleeding was traditionally reversed with fresh frozen plasma and intravenous (IV) vitamin K, but prothrombin complex concentrates (PCC) are increasingly used in the treatment of these patients. Factor Eight Inhibitor Bypassing Activity (FEIBA) is an activated four-factor PCC most commonly used in patients with hemophilia. We aimed to evaluate the efficacy and safety of FEIBA and IV vitamin K for the reversal of warfarin-associated coagulopathy in patients with major bleeding, by measuring the percentage of patients who achieved target INR ≤ 1.5 and the incidence of thrombotic adverse events (TAE).

In this prospective observational study, we enrolled patients presenting to the Emergency Department (ED) with warfarin associated coagulopathy (INR > 1.5) and major bleeding. Patients received FEIBA using an INR based dosing strategy and IV vitamin K.

In 43 patients, median initial INR was 4.0 (2.7, 7.3 interquartile range (IQR)). Median time to result the second INR was 45 min (38, 55 IQR) and the median INR was 1.4 (1.3, 1.6 IQR). Out of the 43 patients, 93% achieved the target INR of ≤1.5. In-hospital mortality was 40% (17 patients). There were 11 TAEs in 6 patients (14%); 4 events in 2 patients (5%) were attributed to FEIBA.

A protocolized use of FEIBA and IV vitamin K resulted in the efficacious reversal of warfarin-induced coagulopathy in patients with major bleeding. TAEs occurred in 14% of patients and were attributed to FEIBA in 5% of patients.