Additive solutions for better blood preservation

For several decades the standard blood preservative solution consisted of citrate, dextrose, and, later, phosphate (ACD and CPD). In 1978 a new solution containing adenine (CPDA-1) was introduced to permit extension of red cell shelf life from 21 to 35 days. The success of CPDA-1 and the high percentage of blood units processed into components (estimated 87% in 1983) have stimulated a burst of research and development activity to develop improved red cell preservation systems. Most of these systems have taken the form of "additive solutions" in which the blood is drawn in CPD or CP2D and processed into components. Then the packed red cells are stored by addition of a solution customized for their preservation. This review evaluates these additive solutions in detail. Innovative systems for pH control (buffers and resins) have also been explored. Our review concludes with discussion of the safety aspects of new preservative solutions and the methodological problems of evaluating these solutions.