title: Possible guidelines for autologous red blood cell donations before total hip arthroplasty based on the surgical blood order equation.
abstract: OBJECTIVE
  To determine, in patients undergoing total hip arthroplasty (THA), clinical predictive criteria for preoperative autologous blood donation and to propose guidelines to increase the efficiency and reduce the cost of preoperative autologous blood donation.
  
  
  METHODS
  In this retrospective analysis of 165 adult patients undergoing primary THA, a stepwise regression analysis was used to determine which clinical variables predict erythropoiesis in patients donating autologous blood before THA. The surgical blood order equation (SBOE), which includes values for hemoglobin lost at surgery, preoperative hemoglobin level, and minimal acceptable hemoglobin level, was used to estimate the number of units of red blood cells (RBCs) needed for each patient at surgery and thus identify which patients should have made preoperative autologous blood donations.
  
  
  RESULTS
  The statistically significant indicators for RBC production were predonation hemoglobin concentration (P<.001) and male sex (P=.003). Combining the regression equation for erythropoiesis with the SBOE allowed development of guidelines for the use of preoperative autologous RBC donation and erythropoietic therapy. For primary THA surgery, a patient with a predonation hemoglobin level higher than 14.7 g/dL does not need preoperative autologous donation. Preoperative autologous RBC donation would be effective for men with hemoglobin concentrations of 14.7 g/dL or less and for women with predonation hemoglobin levels of 13.2 to 14.7 g/dL. In women whose hemoglobin level is less than 13.2 g/dL, erythropoietic therapy should accompany autologous donation.
  
  
  CONCLUSIONS
  Incorporation of patient factors with the SBOE system may result in increased efficiency and decreased cost of autologous blood ordering practices before THA.
authors.affiliation: Department of Anesthesiology, Mayo Clinic Rochester, Minn 55905, USA.
authors.forename: G A
authors.initials: GA
authors.lastname: Nuttall
authors.forename: P J
authors.initials: PJ
authors.lastname: Santrach
authors.forename: W C
authors.initials: WC
authors.lastname: Oliver
authors.forename: M H
authors.initials: MH
authors.lastname: Ereth
authors.forename: T T
authors.initials: TT
authors.lastname: Horlocker
authors.forename: M E
authors.initials: ME
authors.lastname: Cabanela
authors.forename: R T
authors.initials: RT
authors.lastname: Trousdale
authors.forename: D R
authors.initials: DR
authors.lastname: Schroeder
mesh_terms: D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000592:standards; D001804:Blood Transfusion, Autologous / Q000592:standards*; D017707:Erythrocyte Transfusion / Q000592:standards*; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D012189:Retrospective Studies; D014184:Transplantation, Homologous
chemical_list: D006454:Hemoglobins