title: Warfarin therapy and perioperative transfusion requirement with bleeding amount in patients undergoing cardiac surgery with cardiopulmonary bypass: a retrospective study.
abstract: OBJECTIVE
  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
  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.
  
  
  CONCLUSIONS
  In patients on warfarin therapy undergoing cardiac surgery with CPB, warfarin therapy did not significantly increase perioperative transfusion requirement and bleeding.
authors: Department of Anaesthesiology and Pain Medicine, Konkuk University Medical Centre, Konkuk University School of Medicine, Seoul, Korea.
authors: C-S
authors: CS
authors: Oh
authors: J-W
authors: JW
authors: Choi
authors: E
authors: E
authors: Jung
authors: W-S
authors: WS
authors: Kang
authors: S-H
authors: SH
authors: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage*; D016063:Blood Loss, Surgical; D001803:Blood Transfusion; D002315:Cardiopulmonary Bypass; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019990:Perioperative Care; D012189:Retrospective Studies; D014859:Warfarin / Q000008:administration & dosage*
chemical_list: D000925:Anticoagulants; D014859:Warfarin
keywords: blood transfusion; cardiac surgery; international normalised ratio; thromboelastometry; warfarin