Effect of Mode of Agitation on Storage of Platelet Concentrates in PL‐732 Containers for 5 Days1

Abstract

To determine the degree of damage induced by different modes of agitation during storage of platelets for 5 days in polyolefin (PL-732), we studied pH, platelet count, release of lactic dehydrogenase (LDH) and β-thromboglobulin (β-TG), morphology and osmotic recovery. Platelets were maintained at 20–24°C on elliptical, 6 rpm circular, 2 rpm circular and flat bed agitators. Results showed that the most and least effective modes of agitation were the 2 rpm circular and the elliptical rotators, respectively. Elliptical rotators exhibited excessive release of LDH (46%) and β-TG (51%) while the 2 rpm circular model produced significantly less discharge of these proteins (LDH 13%; β-TG 30%; p7.5) when platelet counts were under 1×10⁹/ml. Flat bed shakers and 6 rpm circular agitators were acceptable but flat bed units were unable to resuspend the platelet ‘button’ which forms after the final preparative centrifugation. The 2 rpm circular rotator showed significantly less LDH and β-TG release than did the 6 rpm version (p < 0.05) and permitted smooth resuspension of the platelet ‘button’. Based on our in vitro studies, we conclude that elliptical rotators may not be suitable for storing PL-732 platelet concentrates and that some other form of agitation should be used.