Public Access Defibrillation: Great benefit and potential but infrequently used

In Copenhagen, a volunteer-based Automated External Defibrillator (AED) network provides a unique opportunity to assess AED use. We aimed to determine the proportion of Out-of-Hospital Cardiac Arrest (OHCA) where an AED was applied before arrival of the ambulance, and the proportion of OHCA-cases where an accessible AED was located within 100 m. In addition, we assessed 30-day survival.

Using data from the Mobile Emergency Care Unit and the Danish Cardiac Arrest Registry, we identified 521 patients with OHCA between October 1, 2011 and September 31, 2013 in Copenhagen, Denmark.

An AED was applied in 20 cases (3.8%, 95% CI [2.4 to 5.9]). Irrespective of AED accessibility, an AED was located within 100 m of a cardiac arrest in 23.4% (n=102, 95% CI [19.5 to 27.7]) of all OHCAs. However, at the time of OHCA, an AED was located within 100 m and accessible in only 15.1% (n=66, 95% CI [11.9 to 18.9]) of all cases. The 30-day survival for OHCA with an initial shockable rhythm was 64% for patients where an AED was applied prior to ambulance arrival and 47% for patients where an AED was not applied.

We found that 3.8% of all OHCAs had an AED applied prior to ambulance arrival, but 15.1% of all OHCAs occurred within 100 m of an accessible AED. This indicates the potential of utilising AED networks by improving strategies for AED accessibility and referring bystanders of OHCA to existing AEDs.