Correlation of aggregometry responses to changes in light transmission through platelet packs.

The transmission of light through 22 platelet packs was monitored during storage with a specially designed apparatus in order to estimate the quality of the platelet concentrates without risking contamination. The changes in light transmission during a 7 day storage period were compared with other properties of platelets upon day 1 and day 7, namely aggregometry responses (to collagen, ADP, and calcium ionophore A23187), platelet factor 4 release, lactate dehydrogenase extracellular activity and pH. On day 7 additional aggregometry tests were carried out with pairs of activators (collagen + ADP, collagen + A23187, collagen + epinephrine, and collagen + arachidonic acid). The 8 concentrates judged as being inferior in quality by the optical apparatus also, with 1 exception, showed inferior quality as assessed from aggregometry responses and/or biochemical analyses.