Platelet in vitro assays: their correspondence with their in vivo hemostatic potential

Developments during the past few years have resulted in multiple kinds of platelet products for transfusion. This involves different collection methods, containers, preservative solutions, modifications of storage temperatures and durations, and additional treatments such as pathogen reduction. Much experience has been obtained testing these processes in vitro to seek indications of in vivo effectiveness. Availability of an in vitro method that correlated with in vivo effectiveness would be extremely valuable for these different kinds of platelet products and as more innovation in platelet preparation occurs in the future. This report reviews the methods for in vitro platelet testing with a view to their in vivo implications and whether such testing could be helpful in projecting the clinical effectiveness of different platelet products.