[Reduction of leukocytes and loss of erythrocytes in production of erythrocyte concentrates using the "top and bottom" principle, a comparison between the equipment combinations Biopack-U/Biotrans Separator and Optipac/Optipress].

Using four different centrifugation methods, we compared the combinations of top and bottom bags and blood component separators made by Biotrans and Baxter. Compared with the cell counts of the donated blood, there remained 25% of the leukocytes and 88% of the red blood cells in the red cell preparations following application of the Biotrans system; the respective values for the Baxter system were 20% leukocytes and 85% red cells. The results were not influenced by the centrifugation method used. Thus, febrile nonhemolytic transfusion reactions and immunization against leukocyte antigens can be avoided by neither system.