Reduction of plasma volume after storage of platelets in CP2D

There has been concern that further deterioration might occur if stored platelets are centrifuged to reduce their volume. Although such centrifugation appears to have minimal effect on platelets in CPDA-1 (osmolarity, 470 mOsm) there is no information on the situation with CP2D (580 mOsm).

Platelet concentrates from CP2D packs were sampled at 1 and 5 days and after centrifugation was used to reduce the plasma volume to 10 mL. The aggregation, hypotonic shock response, morphology, pH, and lactate, glucose, pCO2 and pO2 levels were assessed, and values were compared to those seen with CPDA-1. In addition, blood was collected from the same donors into both CP2D and standard sodium citrate anticoagulant in an anticoagulant-to-blood ratio of 1:8 and the aggregation response of the fresh platelets was measured.

Collection of blood into CP2D results in an immediate reduction of the platelet aggregation response when compared to that found after collection of blood into sodium citrate or CPDA-1. Aggregation is further decreased after storage; however, these changes and those for hypotonic shock, pH, lactate, glucose, and pCO2 are similar to those seen for CPDA-1. Additional centrifugation did not cause further change.

Platelets stored in CP2D have reduced in vitro function after 5 days of storage, but subsequent centrifugation to reduce the plasma volume does not further alter these platelets.