The effects of red cell transfusion donor age on nosocomial infection among trauma patients

Association Between Blood Donor Demographics and Post-injury Multiple Organ Failure after Polytrauma

OBJECTIVE

To test the hypothesis that blood donor demographics are associated with transfused polytrauma patients' post-injury multiple organ failure (MOF) status.

SUMMARY OF BACKGROUND DATA

Traumatic shock and MOF are preventable causes of death and post-traumatic hemorrhage is a frequent indication for transfusion. The role of blood donor demographics on transfusion recipients is not well known.

METHODS

A log-linear analysis accounting for the correlated structure of the data based on our prospective MOF database was utilized. Tests for trend and interaction were computed using a likelihood ratio procedure.

RESULTS

A total of 229 critically injured transfused trauma patients were included, with 68% of them being males and a mean age of 45 years. On average 10 units of blood components were transfused per patient. A total of 4379 units of blood components were donated by donors aged 46 years on average, 74% of whom were males. Blood components used were red blood cells (47%), cryoprecipitate (29%), fresh frozen plasma (24%), and platelets (less than 1%). Donor-recipient sex mismatched red blood cells transfusions were more likely to be associated with MOF ( P = 0.0012); fresh frozen plasma and cryoprecipitate recipients were more likely to experience MOF when transfused with a male (vs female) component ( P = 0.0014 and <0.0001, respectively). Donor age was not significantly associated with MOF for all blood components.

CONCLUSIONS

Blood components donor sex, but not age, may be an important factor associated with post-injury MOF. Further validation of our findings will help guide future risk mitigation strategies specific to blood donor demographics.

Identification of unique microRNA expression patterns in bone marrow hematopoietic stem and progenitor cells after hemorrhagic shock and multiple injuries in young and old adult mice

BACKGROUND

After severe trauma, the older host experiences more dysfunctional hematopoiesis of bone marrow (BM) hematopoietic stem and progenitor cells (HSPCs), and dysfunctional differentiation of circulating myeloid cells into effective innate immune cells. Our main objective was to compare BM HSPC microRNA (miR) responses of old and young mice in a clinically relevant model of severe trauma and shock.

METHODS

C57BL/6 adult male mice aged 8 to 12 weeks (young) and 18 to 24 months (old) underwent multiple injuries and hemorrhagic shock (polytrauma [PT]) that engenders the equivalent of major trauma (Injury Severity Score, >15). Pseudomonas pneumonia (PNA) was induced in some young and old adult mice 24 hours after PT. MicroRNA expression patterns were determined from lineage-negative enriched BM HSPCs isolated from PT and PT-PNA mice at 24 and 48 hours postinjury, respectively. Genome-wide expression and pathway analyses were also performed on bronchoalveolar lavage (BAL) leukocytes from both mouse cohorts.

RESULTS

MicroRNA expression significantly differed among all experimental conditions (p < 0.05), except for old-naive versus old-injured (PT or PT-PNA) mice, suggesting an inability of old mice to mount a robust early miR response to severe shock and injury. In addition, young adult mice had significantly more leukocytes obtained from their BAL, and there were greater numbers of polymorphonuclear cells compared with old mice (59.8% vs. 2.2%, p = 0.0069). Despite increased gene expression changes, BAL leukocytes from old mice demonstrated a more dysfunctional transcriptomic response to PT-PNA than young adult murine BAL leukocytes, as reflected in predicted upstream functional pathway analysis.

CONCLUSION

The miR expression pattern in BM HSPCs after PT (+/-PNA) is dissimilar in old versus young adult mice. In the acute postinjury phase, old adult mice are unable to mount a robust miR HSPC response. Hematopoietic stem and progenitor cell miR expression in old PT mice reflects a diminished functional status and a blunted capacity for terminal differentiation of myeloid cells.

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.

Packed red blood cell donor age affects overall survival in transfused patients undergoing hepatectomy for non-hepatocellular malignancy

BACKGROUND

Patients undergoing hepatectomy often require packed red blood cell (PRBC) transfusion, which has been associated with worse oncologic outcomes. However, limited data exist regarding the impact of PRBC donor factors. We hypothesized that PRBC donor age impacts survival after hepatectomy for non-hepatocellular malignancies.

METHODS

Patients who underwent hepatectomy for non-hepatocellular malignancy from 2005 to 2014 were retrospectively evaluated. Impact of clinicopathologic and PRBC factors on oncologic outcomes were assessed.

RESULTS

Of 149 identified patients, 76 received a perioperative PRBC transfusion (median 2 units). Transfusion was associated with increased median length of stay (8 vs. 6 days; p < 0.01) and median operative blood loss (700 vs. 350 mL; p < 0.01) versus non-transfused, respectively. In transfused patients, receipt of PRBC from older donors compared to younger resulted in decreased RFS (0.94 vs. 2.63 years, respectively; p = 0.02) and OS (1.94 vs. 3.44 years, respectively; p = 0.6). The PRBC donor age was an independent predictor of decreased recurrence free survival on multivariate analysis (HR 2.5, p = 0.04).

CONCLUSIONS

In patients undergoing hepatectomy for non-hepatocellular malignancies and receiving perioperative transfusion, PRBC donor age may impact survival and warrants further investigation.