A study of factors influencing the quality of blood products during preparation, storage and filtration

Abstract: The quality of a cell concentrate to be transfused is dependent on the method of preparation and the storage conditions of the blood products. The aim of this study was to determine, compare and evaluate factors influencing the quality of platelet and erythrocyte concentrates. The influence of the method of preparation on platelet concentrates from whole blood and on leukocyte depletion by filtration of erythrocyte concentrates was studied. In addition, the influence of storage on leukocyte depletion by filtration of platelet and erythrocyte concentrates was investigated.The method of preparation of platelet concentrates from whole blood influenced the release from the platelet α-granules. A significant increase in the release was found in the concentrates prepared from platelet-rich plasma compared with buffy coat. If the buffy coat was allowed to rest for <4 hours before centrifugation, this difference was significant until day 3 of storage. The ability of platelets to stimulate the growth of fibroblasts followed a similar course and decreased during preparation and storage.The method of preparation of erythrocyte concentrates was shown to influence the outcome of leukocyte depletion by filtration. When hard spun, buffy coat depleted, concentrates were used, the number of leukocytes found in the filtrate was significantly higher compared with units that had been supplemented with an additional 5 or 10 ml of plasma. The flow rate during filtration and temperature of the unit was also shown to have an influence on the outcome on the number of leukocytes post filtration.The storage time of both erythrocyte and platelet concentrates resulted in significant differences in the number ofleukocytes found after leukocyte depletion by filtration. A short storage time of erythrocyte concentrates was found to give a higher number of leukocytes after filtration compared with a longer storage time. This was in contrast to platelet concentrates where a filtration just after preparation, i.e. no storage time, gave better leukocyte depletion compared with 5 days of storage.The distribution ofleukocyte subsets was also changed significantly by filtration. Comparing the pre- and post-filtration percentages of subsets in platelet concentrates, we found a lower percentage of T-lymphocytes and a higher percentage of B-lymphocytes and monocytes post filtration. In conclusion, the method of preparation of cell concentrates and the storage time have a substantial impact on the properties of the final product. Standardized and controlled procedures are of great importance in making optimal blood products.