Association Between the Level of Prehospital Emergency Services and Mortality Among Road Traffic Injury Patients

Abstract

Background: Road traffic injuries (RTIs) remain a significant public health issue, ranking among the leading causes of mortality and severe disability in Thailand. Prehospital emergency medical services (EMS) play a crucial role in reducing morbidity and mortality through two primary levels of care: First Responder (FR) and Advanced Life Support (ALS). However, the effectiveness of ALS in reducing mortality remains controversial, as ALS is often provided to more severely injured patients.
Objective: To compare 30-day mortality rates among RTI patients transported by ALS and FR and to analyze factors associated with mortality, including transport time and injury severity.
Study design: This retrospective cohort study included 886 RTI patients treated at Surin Hospital’s emergency department between October 2023 and September 2024. Patients diagnosed with RTI-related injuries (ICD-10: S0-S9) were included, excluding those who died at the scene, were referred from other hospitals, or had incomplete data. The primary independent variable was EMS service level (ALS vs. FR), while covariates included Glasgow Coma Scale (GCS), Revised Trauma Score (RTS), Injury Severity Score (ISS), Probability of Survival (PS) score, protective equipment use, and transport time. Multivariate logistic regression was performed to adjust for injury severity and other confounders.
Results: Patients transported by ALS had a significantly higher 30-day mortality rate (ALS: 17.1% vs. FR: 0.9%, p<0.001) than FR. However, after adjusting for injury severity, the odds ratio (OR) for mortality in the ALS group decreased substantially, indicating that ALS itself was not a direct risk factor for mortality but rather reflected the severity of injuries among ALS patients. Additionally, while mean transport times between ALS and FR were not significantly different (p=0.089), the wide standard deviation (SD) in ALS transport times suggests high variability, with prolonged transport times potentially contributing to increased mortality.
Conclusion: While ALS was associated with higher mortality rates, this was largely attributable to patient injury severity rather than ALS care itself. Variability in transport times among ALS cases highlights the need for optimized prehospital time management to reduce potential delays and improve EMS efficiency.