Storage of whole blood overnight in different blood bags preceding preparation of blood components: in vitro effects on red blood cells

Background. Routines for the storage of whole blood (WB) overnight for the preparation of blood components on the following day are of increasing interest primarily for logistic reasons. The present study focuses on in vitro effects during storage for 6 weeks on red blood cells (R BC) prepared in different blood containers after being held overnight. Study design and methods. Five different blood collection systems were used with either inline leucocyte reduction red cell filters for the preparation of RBC, buffy coat (BC) and plasma or WB filters for the preparation of RBC and plasma. A new container with an integrated WB filter removing leucocytes but not platelets was also included for the preparation of leucocyte-reduced RBC, BC and plasma units. Standard CPD solution (63 or 70 mL) and SAG-M solution (100 or 110 mL) were used for the collection of either 450 or 500 mL blood. All WB units were stored at room temperature, either overnight for 18-24 hours (test groups, n=104) or for up to 8 hours (reference groups, n=20). In addition, five test units were stored overnight under refrigeration. Results. In test groups (overnight storage at room temperature) we found significantly lower levels of extracellular potassium, 2,3-DPG and pH (up to day 28). During storage, higher levels of ATP (Terumo, CaridianBCT until day 35, Fresenius until day 14, Fenwal throughout storage) were seen in test groups than in reference groups. When WB was stored overnight at 2-6 degrees C before WB filtration, the levels of ATP and haemolysis were higher than in the corresponding reference. Conclusion. Significant differences in in vitro parameters were observed between RBC prepared within 8 hours and 18-24 hours after blood collection. The results were consistent irrespective of the blood container used. New alkaline solutions may decrease the differences.