Evaluation of platelet additive solution for prolonging storage of functional canine platelet concentrate

Objective: To assess storage lesion development, platelet function, and bacterial growth in canine platelet concentrates (PCs) stored in a platelet additive solution (PAS) or a plasma control at 4degree celsius for 21 days.Design: Prospective, ex vivo, experimental controlled study.Setting: University veterinary teaching hospital.Animals: Ten units of canine PCs collected from blood bank donations.Interventions: The PCs were separated into 2 bags, 1 containing 100% plasma and the other containing 35% plasma and 65% of a PAS (Plasma-Lyte A), and stored at 4degree celsius for 21 days. At days 0, 7, 14, and 21, PCs were analyzed for the presence of swirling, aggregate formation, platelet counts, platelet indices, glucose, lactate, lactate dehydrogenase, Pvco(2), Pvo(2), aggregation via light aggregometry, activation percentages using flow cytometry, and bacterial growth.Measurements and main results: Cold-stored PCs in both PAS and plasma control maintained mean pH >6.8 and mean lactate <9.0 mmol/L over 21 days, with no difference in glucose utilization. Swirl was maintained in both solutions for most days (76/80 combined total samples), with no difference in aggregate formation between solutions. The Pvco(2) was higher in plasma on all days (P < 0.001), with no difference in Pvo(2). Platelet indices did not reflect significant storage lesion development in either solution. Lactate dehydrogenase did not differ between solutions but did increase from day 7 to day 21. Mean maximal aggregation percentage was reduced overall but with no significant difference between solutions. The only observed difference in mean activation percentage between solutions was in PAS on day 7, which was significantly higher than plasma (P < 0.05). No bacterial growth occurred during storage.Conclusions: Cold storage in PAS and plasma allowed PCs to be stored for up to 21 days with minimal storage lesion development, maintenance of platelet function, limited platelet activation, and no bacterial growth within stored bags.