IMPROVEMENT OF PLATELET STORAGE-CONDITIONS BY USING NEW POLYOLEFIN CONTAINERS

BACKGROUND: Storage of pooled platelet concentrates (PCs) with yields above 3.0 x 10(11) platelets per unit in a I-L PL-732 polyolefin conta iner for 5 days often results in a drop in pH to below 6.0. Recently, new oxygen-permeable platelet containers (l-L PL-2410, l-L and 1.5-L C ompoflex) have been developed. The maximal platelet storage capacities of the new containers and the PL-732 were compared. STUDY DESIGN AND METHODS: Large platelet pools (n = 27) with platelet concentrations be tween 1.2 and 1.4 x 10(11) per L were made from 3 to 5 PCs prepared fr om buffy coats. The pools were divided in equal volumes among the PL-7 32 and the three new platelet containers. Platelet counts in the PCs r anged from 1.0 to 5.0 x 10(11) per unit. All PCs were stored on a flat bed shaker at 22 +/- 2 degrees C and evaluated on Days 1, 3, 5, and 7 by measuring platelet count, pH, pO(2), pCO(2), HCO3-, glucose, lactat e, platelet swirling, and soluble p-selectin. RESULTS: Day 7 storage o f PCs (n = 6) with yields between 3.0 and 4.0 x 10(11) platelets in PL -732 showed mean +/- SD pH values of 5.93 +/- 0.05 and lactate values of 32.3 +/- 7.9 mmol per L; in 4 of these 6 PCs, pH was below 6.0. In contrast, storage of these PCs in I-L PL-2410 and 1.5-L Compoflex cont ainers and of 2 of these 6 PCs in l-L Compoflex containers showed pH v alues above 6.8. Lactate values were 15.5 +/- 1.3, 15.3 +/- 1.8, and 1 9.5 +/- 4.7 mmol per L, respectively (p <0.001 vs. PL-732). The platel et storage capacity of the new containers with platelet yields between 4.0 and 5.0 x 10(11) per unit (n = 6) was evaluated. Day 7 storage of these PCs in the 1.5-L Compoflex showed an average pH value of 6.74 /- 0.20; in 2 of 6 PCs, pH was below 6.8. The average pH value in the PL-2410 was 6.38 +/- 0.31, and in all PCs, pH was below 6.8. Average l actate values were 17.8 +/- 5.7 and 25.8 +/- 5.6 mmol per L (p <0.05,) respectively. Soluble p-selectin values on Day 7 of storage increased approximately twofold in all PCs. CONCLUSION: The new oxygen-permeabl e containers showed platelet quality comparable to that with the PL-73 2 and for longer storage periods and at higher platelet counts.