Abstract
A quantitative index of the change in the shape of red blood cells during storage, a morphology score, was devised. The score is calculated from the percentage of red cells of each of the four morphological types multiplied by the following factors: discocyte x3, echinocyte-I x2, echinocyte-II x1 and spherocyte x0. The decrease in the morphology score of red cells during stroage was similar to that in ATP levels, though at a little slower pace. The pattern of changes in the morphology score showed an almost negative relationship to that of hemolysis. A comparison of the data of these indicies with those of post-transfusion viability suggested that the morphology score correlates more directly to in vivo viability than ATP levels and hemolysis do. The score was used to evaluate various artificial preservatives containing adenine and the integrity of modified red cells such as washed red cells and frozenthawed red cells during storage. We think that the morphology score is useful as an index for judging the storage condition of red blood cells.
