title: Derivation of a risk index for the prediction of massive blood transfusion in liver transplantation.
abstract: Massive blood transfusion (MBT) remains a serious and common occurrence in liver transplantation surgery. This retrospective cohort study was undertaken to identify preoperative predictors of MBT and to develop a risk index for MBT in liver transplantation. Data were retrospectively collected on all liver transplantations carried out at a single institution between January 1998 and March 2004. Multivariable logistic regression analysis was used to identify independent predictor variables of MBT, defined as >/=6 units of red blood cell concentrate (RBC) in the first 24 hours of surgery. The model was internally validated by bootstrapping. Of the 460 liver transplant recipients, 193 (42%) received >/=6 units of RBC within 24 hours of surgery. Unadjusted analyses identified 12 preoperative predictors of MBT: age, height, gender, repeat transplantation, etiology of liver failure, and preoperative laboratory values (hemoglobin concentration, platelet count, international normalized ratio for prothrombin activity [INR], albumin, total bilirubin, and creatinine). In multivariable logistic regression, 7 independent predictors of MBT were identified: age (>40 years), hemoglobin concentration (</=10.0 g/dL), INR (1.2-1.99, and >2.0), platelet count (</=70 x 10(9)/L), creatinine (>/=110 micromol/L for female subjects and >/=120 micromol/L for male subjects), albumin (< 28 g/L), and repeat transplantation. The area under the receiver-operating characteristic curve (ROC) for the model was 0.82. By using the regression beta coefficients to derive weights for each of these predictors, a risk index was developed that assigned each patient a score between 0 and 8. The ROC for this risk index was 0.79. MBT in liver transplantation surgery can be accurately predicted by 7 readily available preoperative predictors.
authors.affiliation: Department of Anesthesia and Pain Management, University of Toronto, Toronto, Ontario, Canada. stuart.mccluskey@uhn.on.ca
authors.forename: Stuart A
authors.initials: SA
authors.lastname: McCluskey
authors.forename: Keyvan
authors.initials: K
authors.lastname: Karkouti
authors.forename: Duminda N
authors.initials: DN
authors.lastname: Wijeysundera
authors.forename: Karen
authors.initials: K
authors.lastname: Kakizawa
authors.forename: Mohammed
authors.initials: M
authors.lastname: Ghannam
authors.forename: Ahmed
authors.initials: A
authors.lastname: Hamdy
authors.forename: David
authors.initials: D
authors.lastname: Grant
authors.forename: Gary
authors.initials: G
authors.lastname: Levy
mesh_terms: D000328:Adult; D000367:Age Factors; D015331:Cohort Studies; D017707:Erythrocyte Transfusion; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D016031:Liver Transplantation; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D011237:Predictive Value of Tests; D011300:Preoperative Care; D012372:ROC Curve; D012086:Reoperation; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods
chemical_list: D006454:Hemoglobins