The effect of temperature and mode of agitation on the resuspension of platelets during preparation of platelet concentrates.

A problem arose in a blood bank in which about 10 percent of platelet concentrates (PC) observed at day 1 had a large number of macroscopic aggregates. The aggregates were clumps of platelets that did not go into suspension during preparation of PC. These units were set aside for observation. A maximum of 25 percent were stored on a circular rotator; the remainder were stored on either an elliptical rotator or horizontal shaker. By the end of storage, 6 percent of the units still had a large number of clumps. This percentage was reduced to 2.4 percent, when all clumped units were stored on a circular rotator. The number of clumped units observed at day 1 and at the end of storage were reduced dramatically when the temperature of the laboratory (18-19 degrees C), centrifuge (20 degrees C) and storage environmental chamber (22 degrees C) were increased to 24 degrees C. The units with clumps at day 5 were reduced from 225 (out of 8316) to 25 (out of 7137).