Prestorage Leukoreduction Ameliorates the Effects of Aging on Banked Blood

Abstract

Background Prior studies have demonstrated that the transfusion of older blood is independently associated with higher rates of infectious complications, multiorgan failure, and mortality. Putative mechanisms implicate leukocytes in stored blood which generate immunomodulatory mediators as the stored blood ages. The purpose of this retrospective cohort study was to describe the effect of prestorage-leukoreduction (PS-LR) on the detrimental clinical effects of increasing age on blood products utilized in trauma patients. Methods All patients receiving ≥6 units of packed red cells and surviving ≥48 hours since May, 1999 when institutional universal PS-LR was begun were identified. Transfusion requirements, demographic data, and causes of death were collected. Blood bank records were reviewed to determine the age of each unit of blood transfused. Multivariate logistic regression was used to determine the relationship between the age of PS-LR blood transfused and mortality after adjusting for total transfusion requirement, patient age, ISS, Head AIS, mechanism of injury, and gender. A subgroup analysis was performed excluding those patients in whom care was withdrawn at 48–72 hours post-injury for brain death or neurologic devastation. Results A total of 399 patients, receiving 6,603 units of blood, met inclusion criteria. Mortality analysis showed that increasing ISS, patient age, head AIS, and number of units of packed red cells transfused were all independently associated with an increased risk of death. When mean age of blood was analyzed as a continuous variable, a significant reduction in the risk of death with increasing mean age of transfused PS-LR blood was noted (OR 0.959; 95% CI 0.924–0.996). Both of these findings persisted when the mean age of blood was dichotomized at 14 days (OR 0.426; 95% CI 0.182–0.998) and 21 days (OR 0.439; 95% CI 0.225–0.857). The area under the curve for the receiver operating characteristics of our mortality model was 0.90. After excluding 13 patients in whom care was withdrawn 48–72 hours post-injury for brain death or neurologic devastation, the mortality analysis still showed that increasing injury severity, number of units of packed red cells transfused, and age were all independently associated with an increased risk of death. The protective effect of receiving older blood seen in the all-cause mortality analysis disappeared as no association was found between odds of dying and increasing age of PRBC units transfused. This was true whether the mean age of blood transfused was dichotomized at 14 days (OR: 0.93; CI: 0.30–2.83) or at 21 days (OR: 0.54; CI: 0.25–1.16). Conclusion Our data suggest that the deleterious effects of aging on banked blood are ameliorated by PS-LR. We are currently conducting a prospective observational study in an effort to duplicate the findings of this retrospective investigation.

Impact of the age of stored blood on trauma patient mortality: a systematic review

“…Our search strategy is shown in Figure 2. 31 Murrell et al 36 Phelan et al 35 Spinella et al 32 Weinberg et al 33 Weinberg et al 30 Weinberg et al 34 No Definitions for the age of stored blood varied among the 7 studies. Blood was considered old if it was in storage 14 days or longer, 30,33,34 longer than 14 days, 31 or 28 days or longer.…”

“…Blood was considered old if it was in storage 14 days or longer, 30,33,34 longer than 14 days, 31 or 28 days or longer. 32 One study 35 used the mean age of all units received within 14 days to define new blood and the mean age of all units stored 21 days or longer to define old blood, and 1 study 36 developed a composite variable that was defined by the proportionate age of each blood unit averaged over all units transfused and then multiplied by the total number of units transfused. The 7 studies also differed considerably in their eligibility criteria and the volume of pRBCs transfused.…”

“…Within these 7 studies, there was substantial heterogeneity in the applied defin itions for old versus new blood. The storage time after which new blood was defined as old 31 Murrell et al 36 Phelan et al 35 Spinella et al 32 Weinberg et al 33 Weinberg et al 30 Weinberg et al *Based on the Newcastle-Ottawa Quality Assessment Scale for cohort studies, each study was awarded a maximum of 1 star for each item within the Selection and Outcome categories, and a maximum of 2 stars for the Comparability category. Total scores for each study were calculated by adding 1 point for each star awarded, with a maximum possible score of 9.…”

“…This cutoff is derived from several biochemical laboratory studies demonstrating that physiologic changes occur within stored blood, and that after 14 days in storage these changes may have a negative impact in transfusion recipients. 43 We identified only 1 study 35 that analyzed the mean age of blood as a continuous variable. Within our included studies, there was considerable variability among the definitions used for the age of blood in storage, making it difficult to compare studies since blood considered to be old in one study would be considered new in another.…”

“…Evidence for an association between the age of blood and inhospital mortality was conflicting, as 4 studies 30,32-34 found transfusion of older blood to be associated with increased mortality in trauma patients, while 3 studies 31,35,36 reported no increase in mortality associated with older versus newer blood. Two studies transfused RBCs that had been leukoreduced before storage; 1 study 35 reported no increased risk of death associated with transfusion of prestorage leukoreduced RBCs but could not determine whether the effect on mortality was neutral or protective, and another study 33 reported increased mortality associated with transfusion of older blood despite universal leukoreduction.…”