A comparison of methods of determining the 100 percent survival of preserved red cells

Publisher Website
Google Scholar
Abstract
Studies were done to compare three methods to determine the 100 percent survival value from which to estimate the 24‐hour posttransfusion survival of preserved red cells. The following methods using small aliquots of 51Cr‐labeled autologous preserved red cells were evaluated: First, the 125I‐albumin method, which is an indirect measurement of the recipient's red cell volume derived from the plasma volume measured using 125I‐labeled albumin and the total body hematocrit. Second, the body surface area method (BSA) in which the recipient's red cell volume is derived from a body surface area nomogram. Third, an extrapolation method, which extrapolates to zero time the radioactivity associated with the red cells in the recipient's circulation from 10 to 20 or 15 to 30 minutes after transfusion. The three methods gave similar results in all studies in which less than 20 percent of the transfused red cells were nonviable (24‐hour posttransfusion survival values of between 80–100%), but not when more than 20 percent of the red cells were nonviable. When 21 to 35 percent of the transfused red cells were nonviable (24‐hour posttransfusion survivals of 65 to 79%), values with the 125I‐albumin method and the body surface area method were about 5 percent lower (p less than 0.001) than values with the extrapolation method. When greater than 35 percent of the red cells were nonviable (24‐hour posttransfusion survival values of less than 65%), values with the 125I‐albumin method and the body surface area method were about 10 percent lower (p less than 0.001) than those obtained by the extrapolation method.(ABSTRACT TRUNCATED AT 250 WORDS)