Storage of single donor platelet concentrates: paired comparison of storage as single or double concentrates.

Modern cell separators allow the collection of two plateletpheresis concentrates (PCs) at one session. This study evaluates the quality of PCs stored as double concentrates in standard storage containers of two manufacturers. We collected 20 PCs that contained 4.5 x 10(11) platelets in 375 ml plasma (10 using the COBE Spectra and 10 using the Fresenius AS.TEC 204 with 500 ml bags) that were split into one unit of 3.0 x 10(11) platelets in 250 ml (3.0-PC) and one of 1.5 x 10(11) platelets in 125 ml (1.5-PC). Storage of one 3.0-PC per bag of a two-bag system corresponded to storage conditions for double PCs and storage of one 1.5-PC per bag to storage conditions of single PCs. Cell counts, blood gas analysis, glucose and lactate levels, platelet aggregation, and activation and plasma levels of beta- thromboglobulin (beta-TG) and complement factor 3a (C3a) were measured before storage and again on days 3 and 5. COBE 3.0-PCs demonstrated less pH rise, lactate production, CD 62P expression and beta-TG plasma levels, and better aggregability after storage than COBE 1.5-PCs. Fresenius 1.5-PCs had similar platelet quality to COBE 3.0-PCs. Fresenius 3.0-PCs showed a fall of pH (day 5: 6.22 +/- 0.56), the highest amount of anaerobic glycolysis compared to all other storage conditions investigated, high CD 62P- expression and beta-TG plasma levels, and impaired aggregability on days 3 and 5. The highest C3a levels were found in COBE 1.5-PCs. 3.0 x 10(11) platelets in 250 ml plasma should be stored either in one bag of the COBE system or in two 500 ml bags of the Fresenius system. The COBE two-bag system allows the storage of two PCs without loss of platelet quality. Two PCs should not be stored in the Fresenius C4L 500 ml storage containers.