STORAGE OF PLATELETS IN ADDITIVE SOLUTIONS - THE EFFECT OF CITRATE AND ACETATE IN INVITRO STUDIES

The in vitro effects of storage of platelets prepared from 6 pooled buffy coat units and stored in a platelet storage medium consisting of CPD and plasma and different platelet additive solutions were evaluated. The total count of platelets per pooled unit included in the present investigation (n = 20) was 335 +/- 35 x 10(9) (mean +/- SD), Measurements of pH, PO2, pCO2, glucose, lactate, ATP, total adenine nucleotide content, and extracellular adenylate kinase activity were performed in a three-part study. The observations were 1) During storage in saline and citrate (10 mmol/L of citrate), the consumption of glucose and the production of lactate were significantly increased over the values with storage in saline, which were used as a reference. The values for pH at Day 6 were significantly lower. 2) The effects of different concentrations (10, 20, and 30 mmol/L) of acetate in saline were studied. With the exception of significantly higher pH values in saline and acetate, no significant differences were seen in the effects with saline and those with saline and acetate. 3) The combined effect of citrate and acetate was evaluated. The consumption of glucose and the production of lactate, the values for PO2, and extracellular adenylate kinase activity were significantly lower with saline and citrate and acetate than with saline and citrate. Significantly higher values for pH were found at Day 5. The results of these studies indicate that an increase in the concentration of citrate in a platelet storage medium from approximately 8 mmol per L (saline) to 14 mmol per L or more (saline and citrate media) is associated with significantly increased consumption of glucose and production of lactate. This effect can be reversed by the addition of acetate and can be reduced to the same levels that were found with saline.