Neurological outcomes in traffic accidents: A propensity score matching analysis of medical and non-medical origin cases of out-of-hospital cardiac arrest

Abstract

Aim: This study aimed to comprehensively compare the characteristics of out-of-hospital cardiac arrest (OHCA) with medical and non-medical origins attributed to traffic accidents and explore the potential association between the cases with a medical origin and neurologically favorable outcomes.

Methods: In this retrospective nationwide population-based study, baseline data were collected between January 2018 and December 2020. We analyzed 5091 OHCA associated with traffic accidents on the road scene. Only those encounters involving treatment or transport by prehospital emergency medical technicians were included. The characteristics of OHCA incidents and their outcomes were analyzed by categorizing patients into "medical origin" and "non-medical origin" groups.

Results: Medical-origin cases exhibited several distinct characteristics, including higher frequencies of occurrence during the daytime (79.3% [706/890] vs. 68.9% [2895/4201], p < 0.001), a higher prevalence among male (77.8% [692/890] vs. 68.3% [2871/4201], p < 0.001) and younger patients (median [25-75%]: 63 years [42-77] vs. 66 years [50-76], p = 0.003), a higher proportion of shockable initial rhythms(10.5% [93/890] vs. 1.1% [45/4201], p < 0.001), an increased number of cases requiring advanced airway management (33.8% [301/890] vs. 28.5% [1199/4201], p = 0.002) and adrenaline administration by emergency medical teams (26.9% [239/890] vs. 21.7% [910/4201], p < 0.001), and shorter transport times (55.3% [492/890] vs. 60.9% [2558/4201], p = 0.002) compared to non-medical-origin cases. However, medical-origin cases also had lower witness rates (42.8% [381/890] vs. 27.2% [1142/4201], p < 0.001) and were less likely to be transported to higher-level hospitals (55.3% [492/890] vs. 60.9% [2558/4201], p = 0.002). Propensity score matching analysis identified factors associated with favorable neurological outcomes in medical-origin traffic accidents. The adjusted odds ratios were as follows: 8.46 (3.47-20.61) for cases with shockable initial rhythms, 2.36 (1.01-5.52) for cases involving traffic accidents due to medical origin, and 0.09 (0.01-0.67) for cases where advanced airway management was provided.

Conclusion: In this retrospective study, the occurrence of OHCAs of medical origin involving traffic accidents were associated with favorable neurological outcomes. These cases more frequently demonstrated favorable factors for survival compared to those classified as of non-medical origin. The findings have important implications for public health and EMS professionals, they will guide future research aimed at optimizing prehospital care strategies and improving survival rates for similar cases.

Keywords: Characteristics; Medial origin; Out-of-hospital cardiac arrest; Outcome; Traffic accidents.