Change in outcomes for trauma patients over time: Two decades of a state trauma system

Abstract

BackgroundTrauma center mortality rates are benchmarked to expected rates of death based on patient and injury characteristics. The expected mortality rate is recalculated from pooled outcomes across a trauma system each year, obscuring system-level change across years. We hypothesized that risk-adjusted mortality would decrease over time within a state-wide trauma system. MethodsWe identified adult trauma patients presenting to Level I and II Pennsylvania trauma centers, 1999–2018, using the Pennsylvania Trauma Outcomes Study. Multivariable logistic regression generated risk-adjusted models for mortality in all patients, and in key subgroups: penetrating torso injury, blunt multisystem trauma, and patients presenting in shock. ResultsOf 162,646 included patients, 123,518 (76.1%) were white and 108,936 (67.0%) were male. The median age was 49 (interquartile range [IQR] 29–70), median injury severity score was 16 (IQR 10–24), and 87.5% of injuries were blunt. Overall, 9.9% of patients died, and compared to 1999, no year had significantly higher adjusted odds of mortality. Overall mortality was significantly lower in 2007–2009 and 2011–2018. Of patients with blunt, multisystem injuries, 17.7% died, and adjusted mortality improved over time. Mortality rates were 24.9% for penetrating torso injury, and 56.9% for shock, with no significant change. Mortality improved for patients with ISS < 25, but not for the most severely injured. ConclusionsOver 20 years, Pennsylvania trauma centers demonstrated improved risk-adjusted mortality rates overall, but improvement remains lacking in high-risk groups despite numerous innovations and practice changes in this time period. Identifying change over time can help guide focus to these critical gaps.