title: Posttransfusion platelet count increments after ABO-compatible versus ABO-incompatible platelet transfusions in noncancer patients: an observational study.
abstract: BACKGROUND
  Major incompatible platelet (PLT) transfusions have been associated with inferior posttransfusion PLT count increments compared with ABO-compatible transfusions. However, most studies to date have been small and involved hematology/oncology patients.
  
  
  METHODS
  We conducted a prospective observational study in predominantly nononcologic patients to determine whether ABO-compatible (defined as ABO identical and minor incompatible) PLT transfusions resulted in superior posttransfusion PLT count increments. We collected data on consecutive inpatients at Hamilton General Hospital receiving a PLT transfusion during a 50-month period. We compared the absolute count increment (ACI) and corrected count increment (CCI) values in ABO-compatible versus incompatible PLT transfusions. Linear regression was performed to adjust for factors potentially affecting the posttransfusion PLT count response. Univariate models were applied to each explanatory variable with p values of less than 0.10 considered potentially significant. Multivariate models were applied to all potential explanatory variables of interest. p values of less than 0.05 were considered significant.
  
  
  RESULTS
  A total of 1030 transfusions were included in the primary analysis, 73.7% of which were ABO compatible. The median ACI was 35 (interquartile range [IQR], 18-55) for compatible transfusions versus 31 (IQR, 13-51) for incompatible transfusions (p = 0.1480). The median posttransfusion CCI (n = 686) was 18.6 (IQR, 10.2-28.4) for compatible transfusions versus 15.2 (IQR, 4.7-25.7) for incompatible transfusions (p = 0.0499).
  
  
  CONCLUSIONS
  ABO-compatible transfusions in nononcologic patients are associated with a significantly better CCI although the observed difference is small (approx. 20%) and may not be clinically significant.
authors.affiliation: Department of Medicine, McMaster University, and Canadian Blood Services, Hamilton, Ontario, Canada.
authors.forename: Katerina
authors.initials: K
authors.lastname: Pavenski
authors.forename: Theodore E
authors.initials: TE
authors.lastname: Warkentin
authors.forename: Hua
authors.initials: H
authors.lastname: Shen
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Nancy M
authors.initials: NM
authors.lastname: Heddle
mesh_terms: D000017:ABO Blood-Group System / Q000276:immunology*; D000368:Aged; D001787:Blood Group Incompatibility / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D017713:Platelet Transfusion; D011446:Prospective Studies
chemical_list: D000017:ABO Blood-Group System