Two different hematocrit detection methods: Different methods, different results?
- Equal contributors
1 Surgical Intensive Care Medicine, University Hospital of Zurich, CH 8091 Zurich, Switzerland
2 Department of Internal Medicine, Division of Hematology, University Hospital of Zurich, CH 8091 Zurich, Switzerland
BMC Research Notes 2010, 3:65 doi:10.1186/1756-0500-3-65Published: 9 March 2010
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.
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.
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.