title: Gender disparities in red blood cell transfusion in elective surgery: a post hoc multicentre cohort study.
abstract: A post hoc gender comparison of transfusion-related modifiable risk factors among patients undergoing elective surgery.
  
  
  
  23 Austrian centres randomly selected and stratified by region and level of care.
  
  
  
  We consecutively enrolled in total 6530 patients (3465 women and 3065 men); 1491 underwent coronary artery bypass graft (CABG) surgery, 2570 primary unilateral total hip replacement (THR) and 2469 primary unilateral total knee replacement (TKR).
  
  
  
  Primary outcome measures were the number of allogeneic and autologous red blood cell (RBC) units transfused (postoperative day 5 included) and differences in intraoperative and postoperative transfusion rate between men and women. Secondary outcomes included perioperative blood loss in transfused and non-transfused patients, volume of RBCs transfused, perioperative haemoglobin values and circulating red blood volume on postoperative day 5.
  
  
  
  In all surgical groups, the transfusion rate was significantly higher in women than in men (CABG 81 vs 49%, THR 46 vs 24% and TKR 37 vs 23%). In transfused patients, the absolute blood loss was higher among men in all surgical categories while the relative blood loss was higher among women in the CABG group (52.8 vs 47.8%) but comparable in orthopaedic surgery. The relative RBC volume transfused was significantly higher among women in all categories (CABG 40.0 vs 22.3; TKR 25.2 vs 20.2; THR 26.4 vs 20.8%). On postoperative day 5, the relative haemoglobin values and the relative circulating RBC volume were higher in women in all surgical categories.
  
  
  
  The higher transfusion rate and volume in women when compared with men in elective surgery can be explained by clinicians applying the same absolute transfusion thresholds irrespective of a patient's gender. This, together with the common use of a liberal transfusion strategy, leads to further overtransfusion in women.
authors.affiliation: Department of Anaesthesiology and Intensive Care, General Hospital Linz, Vienna, Austria.|AIT Austrian Institute of Technology GmbH 8020, Graz, Austria.
authors.forename: Hans
authors.initials: H
authors.lastname: Gombotz
authors.affiliation: AIT Austrian Institute of Technology GmbH 8020, Graz, Austria.
authors.forename: Günter
authors.initials: G
authors.lastname: Schreier
authors.affiliation: AIT Austrian Institute of Technology GmbH 8020, Graz, Austria.
authors.forename: Sandra
authors.initials: S
authors.lastname: Neubauer
authors.affiliation: AIT Austrian Institute of Technology GmbH 8020, Graz, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Kastner
authors.affiliation: Department of Anaesthesiology, University Hospital Zurich, Zurich, Switzerland.|Faculty of Medicine, School of Surgery, Dentistry and Health Sciences, University of Western Australia, Western Australia, Australia.|Faculty of Health Sciences, Curtin University, Western Australia, Australia.
authors.forename: Axel
authors.initials: A
authors.lastname: Hofmann
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip; D019645:Arthroplasty, Replacement, Knee; D001317:Austria; D016063:Blood Loss, Surgical; D015331:Cohort Studies; D001026:Coronary Artery Bypass; D017558:Elective Surgical Procedures / Q000145:classification*; D017707:Erythrocyte Transfusion / Q000706:statistics & numerical data*; D005260:Female; D054625:Healthcare Disparities / Q000706:statistics & numerical data*; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011184:Postoperative Period; D012307:Risk Factors; D012737:Sex Factors; D016387:Women's Health
chemical_list: D006454:Hemoglobins
keywords: Patient blood management; gender; overuse; transfusion