Improving Bystander Response: How Long Does It Take to Retrieve an AED From Varying Distances.

Abstract

Objectives: Survival from out-of-hospital cardiac arrest (OHCA) is low, with less than 10% surviving to hospital discharge. Early defibrillation can improve survival from an OHCA with a shockable rhythm. Cell phone applications alert rescuers as to where victims are and where automated external defibrillators (AEDs) are located, but guidance on choosing between going to the victim and doing cardiopulmonary resuscitation and retrieving an AED is lacking. We sought to determine the time required to retrieve AEDs at varying distances in a real-life setting. At a distance greater than 400 meters away, that AED retrieval time will be longer than median emergency medical services (EMS) first response time of 6.9 min, based on national data from the Cardiac Arrest Registry to Enhance Survival (CARES) registry.

Methods: Thirty study participants (15 male, 15 female) performed four AED retrieval runs, separated by at least 24 h. Three runs simulated a real-life OHCA situation outdoors on a busy street in our city (in all four seasons), and one was unimpeded on an indoor track. The AED retrieval distances were 200 meters (400 roundtrip), 400 meters (800 roundtrip), and 600 meters (1,200 roundtrip) The middle distance (400/800 meters) was chosen for the track run.

Results: The mean run times were 4.05 min for the 200/400 m retrieval, 6.62 min for the 400/800 m, 8.62 min for the 600/1,200 m, and 4.35 min for the 400/800 m track run, which is 2.3 min shorter than the 400/800 m real-life run and significantly different (p < 0.001).

Conclusions: Barriers to mobility, like traffic lights, motor vehicles, weather conditions, and pedestrians, have significant impacts on how long it takes for an AED to be retrieved and returned to the patient's side. Using these simulation runs, we demonstrated that short AED retrieval distances are likely necessary to impact survival. When compared to our national EMS first response times, only the 200/400 m retrieval distance would likely provide sufficient time for a responder to retrieve, arrive at the patient's side and utilize an AED prior to EMS arrival.