AMBULANCE RESPONSE IN EIGHT MINUTES OR LESS: ARE COMORBIDITIES A FACTOR

Objectives: A recommended emergency medical services (EMS) ambulance response time to a medical emergency is within eight minutes for at least 90% of calls. The study aimed to evaluate elapsed scene times against patient outcomes, injury mechanisms, and comorbidities for rural education and outreach to improve the quality of trauma care.

Methods: This is a single-center study of Trauma Registry data from July 1, 2016, to February 28, 2022. The inclusion criteria were based on age (≥18 years). A logistic regression was performed to ascertain the effects of predictor variables on the likelihood that an adult trauma patient will experience an elapsed scene time greater than 8 minutes.

Results: 19321 patients (mean age 59) were included in the analysis based on the methods section's requirements; 7233 (37%) experienced an elapsed scene time greater than eight minutes. The logistic regression model was statistically significant (N=5297, p< 0.01). The model explained 60% (Nagelkerke R2) of the variance with a greater than eight-minute elapsed scene time and correctly classified 97% of cases (alpha .05). Several significant risk factors for greater elapsed scene times include pre-hospital cardiac arrest (OR=3.08; p<.03), pre-existing chronic renal failure (OR=3.36, p=.05), and alcohol use disorder (OR=1.65, p=.03).

Conclusion: This research identified an opportunity to improve rural trauma team response time, which is only reaching 63% of the patient population within eight minutes. Pre-hospital cardiac arrest and unique pre-existing comorbidities may play a role in extended response times by EMS.