Mechanism of Injury May Influence Infection Risk from Early Blood Transfusion.

Background: Blood transfusion is a known risk factor for infection in trauma patients. Differences based on mechanism of injury have not been well described. We hypothesize that infection risk in trauma patients with early blood transfusion is different based on blunt or penetrating mechanism of injury.
Patients and Methods: Adults admitted to the trauma intensive care unit from January 2010 through January 2015 were reviewed retrospectively. Those receiving transfusion after 24 h were excluded. Infections were defined as positive bronchoalveolar lavage, blood, urine, wound, or abdominal cultures. Logistic regression identified independent predictors of infection. Significance was considered at p ≤ 0.05.
Results: With blunt trauma (n = 625), the transfusion rate was 36% (n = 223), with 30% (n = 186) infections. Those with an infection were more severely injured, had a higher operation rate, lower Glasgow Coma Score (GCS), longer hospital stay, and higher transfusion rate (all p < 0.001). With penetrating trauma (n = 292), the transfusion rate was 54% (n = 159), with 26% (n = 77) infections. Those with an infection were older, more severely injured, had a higher operation rate, lower GCS, longer length of stay, and higher transfusion rate (all p < 0.01). Controlling for age, injury severity score (ISS), revised trauma score (RTS), GCS, and hospital stay, transfusion was an independent predictor of infection in patients with blunt (odds ratio: 2.1, 95% confidence intervals: 1.272-3.393, p = 0.003) but not penetrating trauma.
Conclusions: Early blood transfusion increases infection risk in blunt but not penetrating trauma.