Aim: Direct medical control using video conferencing capabilities of smartphones has never been conducted in out-of-hospital cardiac arrest patients. This study was conducted to investigate the feasibility and treatment effectiveness of real-time smartphone video conferencing calls for the management of out-of-hospital cardiac arrest. Methods: This study was a pre–post-intervention prospective cohort study conducted from January 2013 to July 2015. The intervention was pre-hospital advanced life support under a physician’s direction using a smartphone video call. Results: In total, 942 cardiac arrests occurred over the 2-year period; 308 patients were excluded, and 314 (49.5%) and 320 (50.5%) cardiac arrest patients were enrolled during the pre- and post-intervention study periods, respectively. There were 248/320 (77.5%) cases of smartphone video-assisted advanced life support during the post-intervention period. For patients in the pre- and post-intervention groups, the pre-hospital return of spontaneous circulation was 6.7 and 20%, respectively (adjusted odds ratio 3.3, 95% confidence interval 1.6–6.8, P < 0.01), and favourable neurological outcomes were ascertained in 1.9 and 6.9%, respectively (adjusted odds ratio 23.6, 95% confidence interval 3.4–164.0, P < 0.01). The smartphone voice and video quality were rated 8.5 and 8.2 out of 10, respectively, in physician evaluation, while the overall utility was rated 9.1. Conclusion: We concluded that a multidisciplinary approach including the re-education of basic life support, simulation training for advanced life support, real-time medical direction via video call, and dispatching two teams rather than one team improved the outcome of out-of-hospital cardiac arrest.

Pairs of EMTs maintained high-quality CPR for 16 cycles (32 min) with no decrease in performance. Our findings could provide evidence to recommend guidelines for duration of on-scene CPR for cardiac arrest, particularly in countries where the level and number of ambulance crews are limited.