The effect of continuous dialysis on platelet preservation.

Serotonin uptake and response to hypotonic shock were studied after storage of platelet-rich plasma for three days at 4, 25, and 37 C. Both properties were best maintained at 25 C. The greatly impaired serotonin uptake and hypotonic shock response of platelets stored for three days at 37 C were partly restored by resuspension of the platelets in fresh autologous plasma. No improvement was found when platelets stored at 4 C were resuspended in fresh autologous plasma. When platelet suspensions were stored for three days at 4, 25, and 37 C under continuous dialysis against plasma, the results obtained at 37 C were even better than those obtained with platelets stored at 25 C. These results indicate that if the accumulation of metabolites in the plasma milieu, which in addition to other changes results in a drop of pH, is prevented, the effective storage time of platelet concentrates can be prolonged. The use of a closed plastic dialysis system, based on the triple-bag transfusion set is suggested.