Warfarin therapy and perioperative transfusion requirement with bleeding amount in patients undergoing cardiac surgery with cardiopulmonary bypass: a retrospective study

OBJECTIVES: The study was designed to evaluate the effect of warfarin on perioperative transfusion, bleeding and coagulation status in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). BACKGROUND: There were controversy about the effect of warfarin on perioperative transfusion and bleeding. METHODS/MATERIALS: Medical records from 107 consecutive patients with atrial fibrillation (AF) on warfarin therapy undergoing cardiac surgery with cardiopulmonary bypass (CPB) from 2008 to 2013 at a single university teaching hospital were retrospectively reviewed to compare the patients on to those not on warfarin therapy in terms of perioperative transfusion requirement, postoperative 24-h bleeding amount, and coagulation status assessment using prothrombin time (PT), international normalised ratio (INR) and rotational thromboelastometry (ROTEM®). RESULTS: Although PT/INR was significantly prolonged both before and after surgery in patients on warfarin therapy, ROTEM® data, perioperative transfusion requirement and postoperative 24-h bleeding amount (785 ± 331 vs 676 ± 303 mL, P = 0·089, respectively) were not significantly different between the patients on and those not on warfarin therapy. CONCLUSION: In patients on warfarin therapy undergoing cardiac surgery with CPB, warfarin therapy did not significantly increase perioperative transfusion requirement and bleeding.