Marne Hornblower

Refrigerated Storage of Washed Red Cells

Abstract. Red cells washed and stored in a citrate‐phosphate‐glucose‐adenine solution at pH 7.4–7.6 demonstrate excellent maintenance of adenosine triphosphate, elevation of 2,3‐diphosphoglycerate well above normal levels for more than 6 weeks, reduced hemolysis and 24‐hour in vivo survival comparable to that of cells stored in ADSOL. These results can be attributed in part to a chloride shift in which the washout of intracellular chloride is associated with an influx of OH“, which increases intracellular pH and thereby increases the rate of glycolysis. The phosphate functions primarily as a buffer to maintain both extra‐ and intracellular pH. Reducing the effective osmolality of the storage solution reduces hemolysis and improves cell morphology.

Extending the storage of red cells at 4 °C

Since 1940, when acid-citrate-dextrose (ACD) solution for the anticoagulation and subsequent 21-day storage of whole blood was first introduced in Britain, progress in red cell liquid storage techniques has been intermittent. In 1967, citrate-phosphatedextrose solution (CPD), was licensed for use in the United States although the hope that it might permit an extension of the 3-week shelf-life was not realized. CPD with adeninc (CPDA1) was first used clinically in Germany and subsequently by the US Army leading in 1979 to an extension of shelf-life to 5 weeks. None of these measures substantially affected the maintenance of 2,3-DPG in red cells. DPG starts to fall after 2 or 3 days of refrigerated storage and is essentially gone in 7-10 days. During the 197Os, concern regarding the low PSO of stored red cells led a number of investigators to explore ways of maintaining 2,3-DPG during storage,‘+ none of which was developed to clinical feasibility. It was, however, shown that 2,3-DPG could be rejuvenated by incubation in a solution containing phosphate, inosine, pyruvate and adeninc.’ Rejuvenation can also elevate 2,3-DPG to supra-normal levels and evidence has been presented regarding the benefits of these “super cells” in selected clinical situations.6 Red cell