Cost and outcomes of nosocomial bloodstream infections complicating major traumatic injury.

The objective of this study was to assess the incidence, outcomes, and costs of trauma-related nosocomial bloodstream infection (BSI). This was a 3:1 matched cohort study in patients with severe trauma [defined by an injury severity score (ISS)≥12] admitted to adult or paediatric regional trauma centres over a four-year period. Case patients with nosocomial BSI were matched to controls without a BSI based on predetermined criteria. Outcomes of interest included mortality, length of stay (LOS), and cost attributable to nosocomial BSI. Fifty-seven cases were identified, among whom 51 were successfully matched to three controls. The mean ISS among cases was 30.3, and Staphylococcus aureus was the most commonly isolated pathogen (27%). Being a case was accompanied by a 27% relative increase in the hospital LOS (P=0.02). The odds ratio for 30 day mortality associated with being a case was 5.8 (95% confidence interval (CI): 1.1-30.8; P=0.04). Among survivor-matched groups, being a case was associated with 53% relative increase in the geometric mean total hospital cost [$97,993 (95% CI: $70,143-136,899) for cases and $62,297 (95% CI: $52,155-74,411) for controls, P<0.0001]. This is the first study to show that nosocomial BSI complicating severe trauma is associated with a substantial increase in hospital LOS and in total hospital cost. Our data provide justification to support efforts to reduce the adverse impact of BSI in trauma victims.