IN-PROCESS CELL COUNTS DURING PREPARATION OF PLATELET CONCENTRATES FROM BUFFY COATS

To ensure the quality of platelet concentrates (PCs), we studied in-pr ocess recoveries of blood cell counts in pooled PCs derived from four or five huffy coats (BCs) from Biopack Compoflex Systems in Bern (PC-B C/4 or PC-BC/5) and from five BCs from Optipac (Baxter) in Zurich (PC- BC/5). BCs were pooled employing a sterile connecting device and flush ing them with 300 mL of platelet additive solution. The pools were cen trifuged for 12 min at 500g at 20 degrees C and filtered with PALL's A uto-Stop(TM) BC-leukocyte removal filter. Automated platelet counting was performed on whole blood donation, on single BC, on pooled BC and in the final product. Four out of 10 PC-BC/4 (=40%) and 29 out of 30 P C-BC/5 (=97%) had a total platelet count of >200x10(9) platelets. Aver age percentage recoveries in PC compared to the pre-centrifugation BC pools were similar with the Biopack Compoflex and the Optipac systems, 62% and 57% respectively, whereby the absolute platelet count per one donation was similar, i.e. 49.5x10(9), 55x10(9) and 53x10(9) in PC-BC /4 and PC-BC/5 from Bern and PC-BC/5 from Zurich. There was a signific ant positive correlation between the inital number of BCs taken for po oling and the final platelet counts in the PCs. In order to recover a minimal platelet content of 200x10(9) platelets per pooled unit, it is safer to start out with five rather than with four donations unless r ecoveries during the production steps can be improved. (C) 1997 Elsevi er Science Ltd.