Transfused trauma patients have better outcomes when transfused with blood components from young donors.

The physiology of tissue healing and aging share common pathways. Both patient age and tissue healing are crucial factors predicting outcomes in trauma patients. The presented hypothesis focuses on the concept that transfused trauma patients have better outcomes when transfused with blood components from young donors. The age of the donor of a blood transfusion could affect recovery following a major traumatic insult and help avoid postinjury immune paralysis and its associated complications. The frequent transfusion of blood components to the severely injured trauma patient provides an opportunity for the recipient to benefit from the potentially favourable effect of blood originating from young donors. Different types of evidence support the presented hypothesis including work on soluble circulating factors, research on animal parabiontic models and epidemiological studies. Theories on the role of transfusion of cells, on bone marrow and on senolytics also represent grounds to elaborate pathways to test this hypothesis. The precise molecular mechanism underlying this hypothesis is uncertain. A beneficial effect on trauma patients following transfusion of blood could be due to a positive effect of blood donated from younger donors or instead to the lack of a negative effect possibly occurring when transfusing blood from older donors. Either way, identifying this mechanism would provide a powerful tool enhance long and short term recovery after trauma.