[Oxygen affinity and regeneration capacity of SAG-M and PAGGS-M stored erythrocytes].

In order to estimate the leftward shift of the oxygen dissociation curve of hemoglobin following storage of red blood cells (rbc) in the additive solutions SAG-M and PAGGS-M, respectively, we performed blood gas analyses after equilibrating the cells with a gas mixture containing 4% of O2 and 5% of CO2 at pH 7.4 and 37 degrees C. Additionally, we took advantage of these nearly physiological conditions to measure the recovery of the hemoglobin function in vitro. We observed a good correlation between 2,3-BPG and p50 (i.e. the oxygen tension, at which hemoglobin is half-saturated with oxygen). Within the first 3 weeks of storage, the 2,3-BPG content fell to one fifth of its original value, whereas the p50 declined from 26.6 to about 20 mm Hg. Compared to fresh cells, rbc stored for longer than 3 weeks will thus deliver 30% less oxygen to the myocardium. The rbc's ability to restore these parameters remained unchanged throughout 7 weeks of storage.