Fixed Versus Variable Dosing of 4-factor Prothrombin Complex Concentrate for Emergent Warfarin Reversal

4-factor prothrombin complex concentrate (4FPCC) contains all of the vitamin K-dependent clotting factors inhibited by warfarin, making it desirable for use in warfarin reversal for emergent bleeds. Multiple guidelines currently recommend 4FPCC for warfarin reversal in vitamin K-dependent major bleeding or intracranial hemorrhage. 4FPCC has a fast onset of action and has demonstrated significant reversal of INR within 10 minutes. Its duration of action is up to 8 hours, and for this reason it should be given concurrently with vitamin K. Vitamin K has a delayed onset of action due to its need to stimulate the synthesis of clotting factors so its effects begin as the effects of 4FPCC diminish. 4FPCC is the standard of care treatment for this clinical population in the Regions Hospital Emergency Department.