Additional studies concerning the metabolism of packed erythrocytes in CPD adenine.

Studies concerning the relationship between glucose level, hematocrit to which cells were packed (within three hours of initial collection) and adenosine triphosphate (ATP) concentration were undertaken in CPD supplemented with adenine (0.25 mM final concentration). It was found that apparently adequate ATP levels could be maintained in 90 per cent hematocrit packed units at 42 days only if glucose was present in amounts 1.5 times or greater than that provided by CPD. Less tight packing of the units to 70 and 80 per cent hematocrit maintained ATP at greater than 50 per cent of the initial level for a full 42 days of storage when 1.25 times the usual glucose concentration was present in the initial anticoagulant. No difference in 2,3-diphosphoglycerate or pH was found in any of the modified media under study.