PLATELET CONCENTRATES STORED FOR 5 DAYS IN A REDUCED VOLUME OF PLASMAMAINTAIN HEMOSTATIC FUNCTION AND VIABILITY

Background: Platelet concentrates prepared from whole blood are genera lly suspended in a standard volume of 50 to 60 mL of plasma and can be stored thus at 20 to 24 degrees C for up to 5 days. In vitro studies suggested that this plasma volume could be reduced to 30 to 35 mL with out impairing platelet function.Study Design and Methods: This study e valuated whether platelets stored for 5 days in a reduced volume (30-3 5 mL) of plasma maintained their in vivo viability, hemostatic functio n, and recovery in recipients. Paired autologous platelet survival stu dies were done in 20 adult volunteers to assess platelet viability. A rabbit ear bleeding-time model was used to compare the hemostatic effe ctiveness of human platelet concentrates stored for 5 days in the stan dard or reduced volume of plasma. Platelet recovery was compared in th rombocytopenic hospital patients. Results: Paired platelet survival st udies indicated no significant difference between the values in platel et concentrates stored for 5 days in the reduced volume of plasma and the values in those stored in the standard volume. In the animal model , there was no significant difference in the bleeding times achieved b y either set of platelet concentrates. The platelet count increments i n thrombocytopenic patients were measured. The platelet count incremen ts in patients who received reduced-volume platelet concentrates were as good as the Increments achieved in patients given standard-volume c oncentrates. Conclusion: The in vivo viability, recovery, and hemostat ic function of platelets collected in polyvinylchloride plastic contai ners and stored in 30 to 35 mL of plasma for 5 days are maintained as well as those of platelets stored in 50 to 60 mL of plasma.