Platelet storage media

Platelet additive solutions (PASs) can be used as a substitute for plasma f or the storage of platelet concentrates (PCs) in order to recover plasma fo r other purposes, to avoid transfusion of large volumes of plasma to patien ts, to improve storage conditions, and to make possible photochemical treat ment for viral inactivation of PCs. The effects on platelet metabolism asso ciated with different factors and compounds in PAS are only partly known. A vailable studies suggest that: (1) The presence of glucose in the platelet storage medium during the entire storage period is necessary for platelet m etabolism. (2) Acetate is used as a substrate for platelet metabolism reduc ing production of lactate by platelets. By formation of bicarbonate, it mai ntains stable pH levels during storage. (3) The fall in pH can be rapid in PAS-containing media, due to the very limited buffering capacity of PAS com pared with that of plasma. (4) Platelets stored in PAS at a citrate concent ration of 8 mmol/l produce only half the quantity of lactate as that of pla telets at 14-26 mmol/l of citrate. (5) Free fatty acids from plasma can be used as substrate for platelet metabolism and are supposed to be made avail able by the hydrolysis of plasma triglycerides. (6) For apheresis PCs with ACD anticoagulant, the presence of phosphate in PAS seems to be a critical factor to avoid low adenine nucleotide levels during storage. The results of available studies suggest that PAS for storing platelets has a great potential for wide use in transfusion medicine. A number of intere sting questions regarding the effects of different compounds in PAS are sti ll to be answered. It is expected that answers to these questions will be p rovided over the next few years. (C) 2001 Elsevier Science Ltd. All rights reserved.