Oxygenation properties and intraerythrocytic constituents of human blood when stored in different media of ACD and CPD.

In the blood stored in acid-citrate-dextrose solution (ACD blood), the oxygen affinity and red cell 2, 3-diphosphoglycerate (2, 3-DPG) content showed parallel exponential decays with half-lives of 3 to 4 days. In the blood stored in citrate-phosphate-dextrose solution (CPD blood), the two parameters increased during the first 4 days before showing the same decay as that seen in the ACD blood. There was no significant change in the transmembrane pH gradient of the red cells, and thus the intracellular pH at the plasma pH of 7.40 was always in the range of 7.17 +/- 0.02 throughout the period of storage in ACD medium. In both ACD and CPD blood, the Hill exponent n was always normal (approximately 2.8) while the Bohr coefficient (delta log P50/delta pH) rose along with the lapse of time for preservation. The oxygen affinity of the CPD blood was less influenced by the red cell 2, 3-DPG than was that of the ACD blood. This phenomenon was thought to derive from higher concentration of salts within the CPD-stored red cells. The efficiency of blood oxygen transport in ACD and CPD blood was compared.