Impact of Storage Lesion on Post-transfusion Rise in Hemoglobin

Background: The storage lesion is defined as the set of changes that occur in red blood cells (RBCs) during storage. Studies have shown that a prolonged storage period of RBCs is associated with increased destruction after transfusion. The aim of this study is to determine the impact of the storage lesion on the efficacy of RBC transfusions by comparing the mean rise in the hemoglobin of patients who received new vs old blood. Methods: We did a retrospective chart review of all patients who received a single unit of pure red blood cell (PRBC) transfusion in a three-month period. Patients with hemolytic anemia and active bleeding were excluded. The storage lesion was estimated by calculating the number of days to expiration on the day of transfusion. Median days to expiration was calculated to be 11 days. Patients were divided into two groups based on days to expiration. Group A included patients who received old blood (days to expiration: 0-11) and group B included patients who received new blood (days to expiration: 11-38). The mean rise in hemoglobin between the two groups was compared using the paired t-test. Results: The baseline characteristics of both groups were similar. There was no statistically significant difference in the mean rise in hemoglobin (1.01 vs 1.08- p-value 0.298), hematocrit (3.37 vs 3.61- p-value 0.249), and RBC count (0.42 vs 0.44- p-value 0.097) in the group that received old blood vs new blood, respectively. Conclusion: An RBC transfusion with a shorter storage period does not increase hemoglobin more than RBC with a longer storage period.