Do EMS Physicians Delay On-Scene Times for HEMS Crews?

Helicopter emergency services (HEMS) serve a crucial role in the triage and transport of critically ill patients. Rapid transport to definitive care has become the goal of all prehospital EMS as shorter scene intervals have been associated with decreased mortality. Over the past several years, we have seen a rise in physicians trained in emergency medicine and EMS responding in the prehospital setting in our HEMS region. Our goal is to determine if the presence of EMS physicians on scene calls with HEMS delays time to hospital for patients.

This retrospective chart review collected on-scene time data from January 2016 to November 2020. Data were collected from our regional HEMS provider database via EMSCharts. We compared the HEMS scene intervals between calls which were serviced by HEMS crews alone, versus those where EMS physicians were present. The Wilcoxon rank-sum test was used to compare these two distributions, and a p-value <0.05 was used to determine statistical significance.

We analyzed 1106 scene calls, four of which were excluded as they should have been designated as inter-facility transfers. Our analysis included 1079 scene calls with HEMS crews alone, and 23 scene calls with EMS physicians, with median HEMS scene intervals of 18 min and 19 min, respectively. A Wilcoxon rank-sum test comparing both distributions had a p-value of 0.30 (z= -1.04).

There was no significant difference between HEMS scene intervals at calls serviced by HEMS crews alone versus those where EMS physicians were present. EMS physician presence was not associated with prolonged HEMS scene intervals.