Few studies have discussed whether physician-staffed helicopter emergency medical services (HEMS) provide temporal and geographical benefits for patients in remote locations compared to ground emergency medical services (GEMS). Our study seeks to clarify the significance of HEMS for patients with severe trauma by comparing the mortality of patients transported directly from crash scenes by HEMS or GEMS, taking geographical factors into account.

Using medical records from a single center, collected from January 2014 to December 2018, we retrospectively identified 1674 trauma patients. Using propensity score analysis, we selected adult patients with an injury severity score ≥16, divided them into groups depending on their transport to the hospital by HEMS or GEMS, and compared their mortality within 24 h of hospitalization. For propensity score-matched groups, we analyzed distance and time.

Of the 317 eligible patients, 202 were transported by HEMS. In the propensity score matching analysis, there was no significant difference in mortality between the HEMS and GEMS groups: 8.7% vs. 5.8%, odds ratio (OR), 1.547 (95% confidence interval [CI], 0.530–4.514). The inverse probability of treatment weighting (IPTW): 11% vs. 7.8%, OR, 1.080 (95% CI, 0.640–1.823); stabilized IPTW: 11% vs. 7.8%, OR, 1.080 (95% CI, 0.502–2.324); and truncated IPTW: 10% vs. 6.4%, OR, 1.143 (95% CI, 0.654–1.997). The distance from the crash scene to the hospital was farther in the HEMS group, and it took a longer period of time to arrive at the hospital (P < 0.001).

HEMS may provide equal treatment opportunities and minimize trauma deaths for patients transported from a greater distance to an emergency medical center compared to GEMS for patients transported from nearby regions.