Storage of apheresis platelet concentrates after manual replacement of >95% of plasma with PAS 5.

BACKGROUND AND OBJECTIVES: Recently, a glucose- and bicarbonate-containing additive solution termed PAS 5 demonstrated acceptable 7-day platelet storage after >95% plasma replacement with PAS on the day of collection (Day 0). In this study, we examined platelet storage in >95% PAS 5 after manual washing of Day 1 apheresis platelets in plasma collected using either the Amicus or Trima plateletpheresis devices. MATERIAL AND METHODS: Triple platelet donations in plasma were obtained from Amicus (n = 10) and Trima (n = 10) plateletpheresis devices and stored overnight before being centrifuged and manually processed into three units with the following storage media: 100% plasma, >95% PAS 5 or 65% PAS 5/35% plasma. Platelet units were sampled on Days 1, 5 and 7 of storage using a range of tests recommended by the UK guidelines. RESULTS: The majority of in vitro assay results for platelets in PAS 5 were similar to results in paired 100% plasma platelets (controls). The pH of PAS 5 stored platelet units was above the UK recommended guidelines of 7·4 by Day 5. PAS 5 platelets were no more activated than controls as evidenced by comparable soluble P-selectin levels and CD62p and CD42b expression. PAS 5 platelets also exhibited adhesion and aggregation profiles higher than (Day 1) or comparable to (Days 5 and 7) controls as measured by Impact R. CONCLUSION: The 7-day in vitro storage parameters investigated were comparable between >95% PAS 5 and 100% plasma platelets derived from both Amicus and Trima plateletpheresis devices, with the exception that lactose dehydrogenase release rate and pH were significantly higher in PAS 5 units.

Red cell storage in E-Sol 5 and Adsol additive solutions: paired comparison using mixed and non-mixed study designs.

BACKGROUND AND OBJECTIVES: If transfusion of older stored red cells is found to negatively affect clinical outcome, one possible alternative to shortened outdate is the use of new additive solutions (AS) that ameliorate the storage lesion. Erythro-Sol (E-Sol), a previously developed next-generation AS, has been reformulated into E-Sol 5, which is compatible with current anticoagulants and AS volumes. The effect of E-Sol 5 on red cells during storage compared to current AS has not been reported. MATERIALS AND METHODS: Paired, ABO-matched whole-blood units were collected into CPD anticoagulant, pooled, split and processed into plasma and red cell units with either 110 ml of Adsol or 105 ml of E-Sol 5 within 8 h of collection. In Study 1, paired units in E-Sol 5 and Adsol were sampled on Day 0 and every 7 days up to Day 42 (n = 10). In Study 2, paired units in E-Sol 5 and Adsol were sampled only on Day 0 and Day 42 (n = 10). RESULTS: In Study 1, 2,3 DPG levels were maintained until Day 28 in E-Sol 5 units and Day 14 in Adsol units. ATP levels were higher in E-Sol 5 units until Day 21, after which they were comparable between the two groups. In both studies, metabolic activity was greater in E-Sol 5 units with respect to glucose consumption and lactate production. Morphology scores were higher, and haemolysis and microparticles generated were lower in E-Sol 5 vs. Adsol units. Weekly mixing of units lowered haemolysis and microparticle levels and increased potassium content on Day 42 in both additive solutions. CONCLUSION: Regardless of whether units are mixed weekly or are stored non-mixed, E-Sol 5 slows the progression of the red cell storage lesion and improves the overall in vitro quality of RBC throughout storage.