The mortality benefit of direct trauma center transport in a regional trauma system: A population-based analysis

BACKGROUND By ensuring timely access to trauma center (TC) care, well-organized trauma systems have the potential to significantly reduce injury-related mortality. However, undertriage continues to be a significant problem in many regional trauma systems. Taking a novel, population-based approach, we estimated the potential detrimental impact of undertriage to a non-TC (NTC) within a regional system. METHODS We performed a population-based, retrospective cohort study of TC effectiveness in a region with urban, suburban, and rural areas. Data were derived from administrative databases capturing all emergency department deaths and admissions in the region. Adult motor vehicle collision occupants presenting to any emergency department in the study region were included (2002–2010). Data were limited to patients with severe injury. The exposure of interest was initial triage destination (TC or NTC), regardless of later transfer to TC. Mortality was compared across groups, using an instrumental variable analysis to adjust for confounding. RESULTS Among 6,341 motor vehicle collision occupants, 45% (n = 2,857) were triaged from the scene of injury to a TC. Among patients transported from the scene to a NTC, 57% (n = 2,003) were transferred to a TC within 24 hours of initial evaluation. Compared with patients triaged to a NTC, adjusted mortality was lower among patients triaged directly to a TC, both at 24 hours (odds ratio: 0.58, 95% confidence interval: 0.41–0.84) and at 48 hours (odds ratio: 0.68, 95% confidence interval: 0.48–0.96). A trend toward reduced mortality with TC triage was also observed at 7 and 30 days. CONCLUSIONS Our data are population-based evidence of the early benefits of direct triage to TC. Although many surviving patients are later transferred to a TC, initial triage to a NTC is associated with at least a 30% increase in mortality in the first 48 hours after injury. LEVEL OF EVIDENCE Therapeutic study, level IV.

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