title: Two different hematocrit detection methods: different methods, different results?
abstract: BACKGROUND
  Less is known about the influence of hematocrit detection methodology on transfusion triggers. Therefore, the aim of the present study was to compare two different hematocrit-assessing methods. In a total of 50 critically ill patients hematocrit was analyzed using (1) blood gas analyzer (ABLflex 800) and (2) the central laboratory method (ADVIA® 2120) and compared.
  
  
  RESULTS
  Bland-Altman analysis for repeated measurements showed a good correlation with a bias of +1.39% and 2 SD of +/- 3.12%. The 24%-hematocrit-group showed a correlation of r2 = 0.87. With a kappa of 0.56, 22.7% of the cases would have been transfused differently. In the-28%-hematocrit group with a similar correlation (r2 = 0.8) and a kappa of 0.58, 21% of the cases would have been transfused differently.
  
  
  CONCLUSIONS
  Despite a good agreement between the two methods used to determine hematocrit in clinical routine, the calculated difference of 1.4% might substantially influence transfusion triggers depending on the employed method.
authors.affiliation: Surgical Intensive Care Medicine, University Hospital of Zurich, CH 8091 Zurich, Switzerland.
authors.forename: Marco
authors.initials: M
authors.lastname: Bosshart
authors.forename: John F
authors.initials: JF
authors.lastname: Stover
authors.forename: Reto
authors.initials: R
authors.lastname: Stocker
authors.forename: Lars M
authors.initials: LM
authors.lastname: Asmis
authors.forename: Jörg
authors.initials: J
authors.lastname: Feige
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Neff
authors.forename: Reto A
authors.initials: RA
authors.lastname: Schuepbach
authors.forename: Silvia R
authors.initials: SR
authors.lastname: Cottini
authors.forename: Markus
authors.initials: M
authors.lastname: Béchir