Blood Transfusion is Associated with Infection and Increased Resource Utilization in Combat Casualties

Abstract

Combat casualty care has made significant advances in recent years, including administration of blood products in far-forward locations. However, recent studies have shown blood transfusion to be a significant risk factor for infection and increased resource utilization in critically injured patients. We therefore sought to investigate the incidence of blood transfusion and its association with infection and resource utilization in combat casualties. Prospective data were collected and retrospectively reviewed on 210 critically injured patients admitted to the USNS Comfort over a 7-week period during the 2003 assault phase of Operation Iraqi Freedom. Patients were stratified by age, gender, and injury severity score (ISS). Multivariate regression analyses were used to assess blood transfusion and hematocrit (HCT) as independent risk factors for infection and intensive care unit (ICU) admission controlling for age, gender, and ISS. The study cohort had a mean age of 30 +/- 2 years, a mean ISS of 14 +/- 3, 84 per cent were male, and 88 per cent sustained penetrating trauma. Blood transfusion was required in 44 per cent (n = 93) of the study cohort. Transfused patients had a higher ISS (18 +/- 4 vs. 10 +/- 3, P < 0.01), a higher pulse rate (105 +/- 4 vs. 93 +/- 3, P < 0.0001), and a lower admission HCT (27 +/- 1 vs. 33 +/- 2, P < 0.0001) compared with patients not transfused. Patients receiving blood transfusion had an increased infection rate (69% vs. 18%, P < 0.0001), ICU admission rate (52% vs. 21%, P < 0.0001), and ICU length of stay (6.7 +/- 2.1 days vs. 1.4 +/- 0.5 days, P < 0.0001) compared with nontransfused patients. However, there was no significant difference in mortality between transfused and nontransfused patients. Multivariate binomial regression analysis identified blood transfusion and HCT as independent risk factors for infection (P < 0.01) and blood transfusion as an independent risk factor for ICU admission (P < 0.05). Combat casualties have a high incidence of blood transfusion. Blood transfusion is an independent risk factor for infection and increased resource utilization. Therefore, consideration should be given to the use of alternative blood substitutes and recombinant human erythropoietin in the treatment and management of combat casualties.