The Association between Time Intervals in Emergency Medical Services and In‑hospital Mortality of Trauma Patients

Context: While the clinical practice recommends field stabilization in trauma patients, in some situations, the speed of transport is crucial. Aims: This study aimed to evaluate the association between emergency medical services (EMS) time intervals (response time [RT], scene time [ST], and transport time [TT]) and in-hospital mortality in trauma patients in Tehran, the largest metropolis of Iran. Settings and Design: A prospective cohort study was conducted between May 2017 and April 2018. Methods: All EMS operations related to trauma events in the Tehran city that were transferred to three targeted major trauma centers were included. Statistical Analysis: Logistic regression analysis was used to assess the relationship between EMS time intervals and other risk factors of trauma death. Results: A total of 14,372 trauma patients were included in the final analysis. In-hospital mortality occurred in 225 (1.6%) patients. After adjustment for confounding variables, older age (odds ratio [OR] = 1.04/year), female gender (OR = 2.16), low Mechanism, Glasgow Coma Scale (GCS), age, and arterial pressure score (OR = 0.84 for each unit), low GCS (OR = 0.56 for each unit), longer ST (OR = 1.17/10 min), and longer TT (OR = 1.21/10 min) were found to be risk factors for death in trauma. Conclusions: Our study showed that in-hospital mortality of trauma patients correlated with longer EMS ST and TT, but the RT was not associated with mortality. Our results recommend that the EMS system should consider ST and TT rather than RT, as indexes of quality control in prehospital care of trauma patients.