LAUSR

Background: Although andexanet alfa was recently approved as a specific reversal agent for apixaban and rivaroxaban, some providers still elect to administer 4-factor prothrombin complex concentrate (4F-PCC) instead, due to concerns surrounding efficacy, thrombotic risk, administration logistics, availability, and cost. Previous studies have described success with 4F-PCC doses ranging from 25 to 35 U/kg, with some guidelines recommending 50 U/kg. Objectives: The purpose of this study was to compare hemostasis between patients receiving low- (20-34 U/kg) versus high-dose (35-50 U/kg) 4F-PCC for the urgent reversal of apixaban and rivaroxaban. Patients/Methods: We performed a retrospective cohort study at a level one trauma center and comprehensive stroke center between January 2015 and December 2018. Main exclusion criteria included patients receiving less than 20 U/kg or if postreversal imaging were unavailable. Outcomes assessed included hemostasis for critical bleeding associated with apixaban or rivaroxaban and postoperative bleeding for reversal for emergent procedures. Results: The low-dose strategy was administered to n = 57 (57.6%) patients at a mean dose of 26.6 U/kg. The high-dose strategy was used in n = 42 (42.4%) patients at a mean dose of 47.6 U/kg. There was no difference in hemostasis by dosing strategy (75.4% vs 78.6%, P = .715) or hospital mortality (19.3% vs 35.7%, P = .067). No difference was found for secondary end points, including thrombotic events (5.3% vs 2.4%, P = .635) and hospital length of stay (11.3 vs 12.5 days, P = .070). Conclusions: Our comparison addresses a gap in the literature surrounding optimal dosing and supports a similar efficacy profile between dosing low- versus high-dose treatment.