Evaluation of platelet count and platelet function analyzer - 100 testing for prediction of platelet transfusion following coronary bypass surgery.

Platelet transfusions are commonly administered to treat bleeding in cardiac surgery. The aim of this study was to compare platelet (PLT) count and values of collagen adenosine diphosphate closure time (cADP-CT) measured by Platelet Function Analyzer (PFA) for prediction of PLT transfusion therapy following coronary bypass surgery. For this prospective observational study, 66 patients scheduled for coronary artery bypass grafting (CABG) who received early PLT transfusions (within 60 min after the operation) were enrolled. To assess changes in platelets, count and function, two time points were selected: 15 min before and 30 - 60 min after the end of PLT transfusion. The patients were divided into transfused and non-transfused with further PLT in the 48 h postoperatively. We used the receiver operating characteristics (ROC) curve to investigate whether the PLT count and cADP-CT values were predictors of PLT transfusion. The positive predictive values (PPV) of PLT count and cADP-CT after PLT transfusion for further PLT transfusion were 33% and 86% respectively, with a PLT count threshold of <= 200 x 10(9)/L and cADP-CT threshold of >= 118 s. The comparison among the ROC curves showed a statistical difference (p = .0002). In multiple regression analysis, cADP-CT was the strongest predictor for the number of PLT transfusion doses in the 48 h postoperatively. In CABG patients, the results of cADP-CT after PLT transfusion have a better predictive capacity for further PLT transfusions than the PLT count.