The impact of storage time of transfused RBCs on mortality is still a matter of debate. During storage, biochemical changes occur which are referred to as the “storage lesion”. These changes include decreases in ATP, 2,3-DPG and intracellular potassium concentrations due to alterations of the RBC membrane during storage. Longer storage time of RBCs has been associated with increased mortality in cardiac surgery patients while some studies outside this setting do not confirm this finding. An optimal study design to finally resolve the erythrocyte lesion debate remains crucial.

In the present large retrospective study 6,994 adult general surgical patients were included. Patients were grouped into three RBC storage duration groups based on whether median storage duration was <14 days, >14 days but <28 days, or >28 days. Cox proportional hazards regression was used to analyze the relationship between median RBC storage time and postoperative mortality over time. No association between RBC storage duration and 2-year mortality was found. The authors’ findings are in line with the majority of the most recent literature in surgical and medical patients.

– Rainer Moog