Prediction of the transfusion effect of platelet concentrates as measured by a model of primary hemostasis ex vivo

A method to determine primary hemostasis ex vivo (Thrombostat) was modified to monitor the transfusion effect of platelet concentrates (PC) in 12 patients with thrombocytopenia following bone marrow transplantation. It was possible to measure platelet function in patients with a platelet count lower than 2 x 10(10)/l. In addition, the platelet aggregometer (Born) was adapted to determine cell function in PC anticoagulated with acid citrate dextrose of citrate phosphate dextrose. It was possible to make a prediction (r = 0.89) of the effect of a given PC: on a patient's ex vivo primary hemostasis parameters. Platelet aggregation following addition of 20 mu M ADP to PC, obtained from 12 single donors, resulted in an average maximal light transmission (light transmission/age of concentrate in days) of 61%/1 day and 37%/5 days, respectively. The same experiment gave only 39%/1 day and 13%/4 days for pooled platelets. To avoid possible immunization and bleeding complications, a reliable monitoring of platelet transfusion seems highly desirable.