Background and Goal of Study: Red blood cell transfusion and massive blood transfusion are independent risk factors for mortality. Prolonged stored packed red blood cells (PRBC) might increase morbidity and mortality. Therefore, we tested whether prolonged storage increases mortality in patients receiving massive transfusion after trauma needing surgery and surgery related to non-trauma issues. As a secondary hypothesis, we considered the extent to which a differential relationship for trauma and non-trauma patients and mean PRBC storage duration exists.
Materials and methods: With IRB approval, we performed a single center retrospective analysis of patients receiving more than 10 units of PRBC within 24 hours. We evaluated the relationship between patient mean PRBC storage duration and in-hospital mortality using backward stepwise multivariable logistic regression. Potential nonlinearities in the relationship were assessed via restricted cubic splines. The secondary hypothesis was evaluated by considering the interaction between type of surgery (trauma vs. non-trauma) and patient mean PRBC storage duration. 
Results and discussion: The final analysis was done in 305 patients receiving a total of 8046 PRBCs. Patient mean PRBC storage duration ranged from 8 to 36.6 days with a mean ± standard deviation of 22.1 ± 5.9 days. The odds ratio (95% confidence interval (CI)) for in-hospital mortality corresponding to a one-day in mean PRBC storage duration was estimated at 0.99 (0.95, 1.03, P=0.77). We did not find a differential relationship between trauma and non-trauma patients (P=0.75). Data from 259 patients was included into a multivariable analysis but the result did not differ from the univariable analysis and the odds ratio (95% CI) was 0.99 (0.94, 1.05) after adjusting for age, sex, blood type, initial heart rate, initial systolic blood pressure, initial pH, and number of transfused PRBCs were selected for adjustment in the final models.
Conclusion(s): In summary, our data suggest that mean PRBC storage duration does not correlate with patients mortality after massive blood transfusion. Trauma and non-trauma patients did not differ in regard to susceptibility toward prolonged stored PRBCs.

Storage time does not affect outcome after massive blood transfusion in trauma and non-trauma patients