Oxygen Equilibria and Biochemical Changes of Whole Blood Stored in Different Preservation Media

Human blood was stored in its oxygenated and in its deoxygenated forms for a period of 14 to 56 days at 4 C in six different preservation media, namely, ACD and CPD, ACD and CPD supplemented with adenine, ACD and CPD supplemented with adenine and with tris (hydroxymethyl) amino‐methane at pH 7.2. At regular intervals determinations were made of the pH and the oxygen affinities of the total blood, of the intracellular concentrations of ATP, 2,3‐DPG and inorganic phosphate, of plasma electrolytes and lactic add concentrations, and of the minor hemoglobin components. The investigations have shown: 1) Storage of blood in the deoxygenated form results in a rapid decrease of the blood pH, an increased lactic acid production, and a less rapid change in the oxygen affinities and 2,3‐DPG levels; 2) Storage of blood at a more neutral pH prevents the changes in 2,3‐DPG level and oxygen affinity; 3) Supplementation of the media with adenine may increase to some extent the ATP level of the red blood cells; 4) No significant changes are observed in the percentages of the minor hemoglobins. A striking correlation was observed between the oxygen affinity of the blood and the intracellular 2,3‐DPG level; no such correlation was present between the ATP level of the red blood cells and the oxygen affinity of the blood. The 2,3‐DPG level (and the oxygen affinity) was also dependent on the pH of the blood‐preservation media. A rapid disappearance of 2,3‐DPG was noted below rather fixed pH values; these pH values were consistently lower when blood was stored in its deoxygenated form than in its oxygenated form.