Platelet collection with the Autopheresis-C apheresis system.

This report describes a new system for collection of platelet concentrate (PC) and cell-free plasma (PPP) from apheresis donors. The system uses two separation devices and requires only a single venipuncture. The Plateletcell device separates primary platelet concentrate (PPC) from anticoagulated whole blood and the Plasmacell-C device separates the PPC into PC and PPP. Results of functional studies performed indicate that the separation process does not alter viability of either the PPC, the PC, or the PPP. Platelet function after 5 days of storage is maintained. An average yield of 3.4 +/- 0.7 x 10(11) platelets in 201 g of PC and 422 g of PPP were harvested in 71 +/- 13 min of donor time from donors with preprocedure hematocrits averaging 42.5 +/- 2.0% and preprocedure platelet counts averaging 265 +/- 61 x 10(3)/microliters.

The surge technique: a method to increase purity of platelet concentrates obtained by centrifugal apheresis.

A surge technique has been developed to increase the purity of high-yield platelet concentrations prepared on a blood processor with the Latham bowl. The surge technique combines elutriation with centrifugal separation, utilizing plasma recirculated from the plasma/air bag back into the centrifuge bowl to elute platelets from the red cell mass. Platelet concentrates prepared by surge collection with six separation cycles (n = 22), contained an average of 3.9 +/- 1.4 X 10(11) platelets, with 0.15 +/- 0.11 X 10(9) leukocytes, and red cells below the level of detection. The surge technique reduces collection time by 4 minutes per cycle and eliminates the need for a secondary centrifugation; thus, 96 minutes donor processing time would permit eight separation cycles. Platelets collected by the surge technique exhibited unaltered morphology and capacity to take up radioactively labeled serotonin in vitro compared to pre-apheresis controls. Results from in vitro functional studies also indicate that the capacity of platelets collected with the surge technique to respond to various concentrations of adenosine diphosphate, collagen, and thrombin by aggregation and secretion of both serotonin (dense bodies) and beta-thromboglobulin (alpha-granules) was not significantly different (p less than or equal to 0.05) from that of pre-apheresis controls.