Platelet concentrates. Influence of different preparative protocols on the in vitro release reaction.

To determine what effect different preparative protocols and different platelet storage bags have on in vitro release, platelet concentrates were prepared according to two different protocols (group I: 2,200 g for 3.5 min followed by 4,900 g for 5 min; group II: 1,000 g for 9 min and 3,000 g for 20 min). The storage bags used were either a standard polyvinyl chloride (PL-146) or a polyolefin bag (PL-732). The results for platelet concentrates stored in PL-146 showed that while group I had undergone more alpha granule release at 24 and 48 h of storage than had group II, by 72 h both groups showed a similar degree of release. Results for platelets stored in PL-732, however, did not show any significant difference in release between the two protocol groups at any storage time up to 120 h. We conclude that although the preparative protocol used may induce different degrees of platelet release in vitro, the platelet storage bag also has a significant influence on the degree of in vitro damage which occurs during subsequent storage.