Sterilization method of platelet storage containers affects in vitro parameters

Background and Aim Four butyryl trihexyl phthalate plasticized polyvinyl chloride (BTHC-PVC) containers were compared for storage of leukoreduced platelet concentrates (LR-PC): three ethylene oxide (EtO) sterilized (Gambro, Haemonetics, Fresenius), and one steam-sterilized (Fresenius). Methods LR-PCs were made from 5 buffy coats and 300 ml Composol additive solution, and leukoreduced by filtration. Four LR-PCs were pooled and subsequently divided over the 4 BTHC-PVC bags to prevent donor-dependent differences, and sampled for in vitro analysis on day 1, 2, 5, 7 and 9. Results The pH values on day 9 were (mean +/- SD, n = 10): 7.12 +/- 0.03 (Gambro), 7.12 +/- 0.04 (Haemonetics), and 7.07 +/- 0.09 (Fresenius, EtO-sterilized) (not significantly different), vs. 6.91 +/- 0.12 (Fresenius, steam-sterilized; P < 0.001 vs. all EtO-sterilized bags). LR-PCs stored in the steam-sterilized bag exhibited significantly higher glucose consumption and lactate production (P < 0.001 vs. all EtO-sterilized bags). Conclusion All BTHC-PVC containers allow storage of LR-PCs for up to 9 days with good in vitro parameters. However, the method of sterilization affects the storage conditions of the LR-PCs in these bags.