International comparison of prehospital trauma care systems

Given the recent emphasis on developing prehospital trauma care globally, we embarked upon a multicentre study to compare trauma patients' outcome within and between countries with technician-operated advanced life support (ALS) and physician-operated (Doc-ALS) emergency medical service (EMS) systems. These environments represent the continuum of prehospital care in high income countries with more advanced prehospital trauma care systems.

Five countries with ALS-EMS system and four countries with Doc-ALS EMS system provided us with de-identified patient-level data from their national or local trauma registries. Generalised linear latent and mixed models was used in order to compare emergency department (ED) shock rate (systolic blood pressure (SBP) <90mmHg) and early trauma fatality rate (i.e. death during the first 24h after hospital arrival) between ALS and Doc-ALS EMS systems. Logistic regression was used to compare outcomes of interest among different countries, accounting for within-system correlation in patient outcomes.

After adjustment for patient age, sex, type and mechanism of injury, injury severity score and SBP at scene, the ED shock rate did not vary significantly between Doc-ALS and ALS systems (OR: 1.16, 95% CI: 0.73-1.91). However, the early trauma fatality rate was significantly lower in Doc-ALS EMS systems compared with ALS EMS systems (OR: 0.70, 95% CI: 0.54-0.91). Furthermore, we found a considerable heterogeneity in patient outcomes among countries even with similar type of EMS systems.

These findings suggest that prehospital trauma care systems that dispatch a physician to the scene may be associated with lower early trauma fatality rates, but not necessarily with significantly better outcomes on other clinical measures. The reasons for these findings deserve further studies.