[Effect of whole blood preparation and leukocyte filtration on storage of erythrocyte concentrates over 42 days].

Leukocyte reduction prior to storage of red cell concentrates (RCC) may reduce the incidence of HLA alloimmunization and may improve the quality of stored RCC. We tested an RCC leukoreduction filter system (Baxter) with an integrated Pall RCM-1 filter and investigated the filtration efficiency and the impact on red cells during storage for 42 days after different whole-blood preparation procedures. After whole-blood donation, all units (n = 9, +6 unfiltered controls per group) were either stored at 22 degrees C for up to 6 h (groups 1, 2, 3) or for 24 h (group 4) RCC were either prepared from a triple blood bag system (PL 146, groups 1, 2) or were buffy-coat-depleted (PL 2209, groups 3, 4). Groups 1, 3 und 4 were filtered immediately, whereas group 2 was stored another 18 h at 4 degrees C before filtration. Filtration efficiency and filtration time were determined. Hemolysis, ATP, 2,3-diphosphoglycerate (2,3-DPG), glucose, electrolytes, lactate, hematocrit, Hb and pH were quantified weekly. White blood cells (WBC) were reduced by 3-4 log10 to 0.1-0.3 x 10(6) (mean) by filtration (all groups) regardless of the RCC preparation. Mean filtration times were 1 h 36 min, 33 min, 29 min, and 18 min for the groups 1 to 4, respectively. There were no major differences for the in vitro storage values except for hemolysis and pH, which were elevated in all filtered units, and potassium, which was elevated in the unifiltered units. In conclusion, prestorage leukocyte filtration of RCC reduced the WBC by 3-4 log10, whereas the extended filtration time was a major disadvantage.