The use of drone-delivered Automated External Defibrillators in the emergency response for out-of-hospital cardiac arrest. A simulation study.

Background: Drones are now being used to deliver Automated External Defibrillators (AEDs) for out-of-hospital cardiac arrest. Delays occur before (between emergency call and drone take-off) and after drone flight itself (related to bystander interaction with drone/AED). The emergency call-handler may have an important role in helping bystanders retrieve and use an AED.

Methods: Following an emergency (999) call for simulated out-of-hospital cardiac arrests, a remote drone was activated and made autonomous Beyond Visual Line of Sight flights to the scene. Real-time communications between drone operator and call-handler allowed participants to receive updates about drone progress. Outcomes included hands-off CPR time, time away from patient's side retrieving the AED, time from emergency call to start of drone flight, and time from drone arrival to AED shock. We used video-recording, emergency-call audio and post-simulation interviews to gather additional information about participants' experiences.

Results: We conducted 11 single bystander simulations and successfully delivered an AED on 9 occasions. It took (median) 2:18 min (interquartile range, IQR 2:13-2:38 min) from emergency call to drone take-off, and a further 4:35 min (3:39-4:46 min) once the drone had arrived on scene until first shock. Hands-off CPR time was 2:32 min (2:01-2:46 min); 0:16 min (0:13-0:21 min) of this was spent retrieving the AED. Bystanders retrieved the AED safely and interacted well with the drone, but often struggled with AED use.

Conclusion: We demonstrated effective real-time communication during simulations. Drone start-up procedures were quick but there were delays once the drone arrived on scene. Bystanders and call-handlers need more support to effectively use drone-delivered AEDs.