Survival after Public Access Defibrillation in Stockholm, Sweden--A striking success.

Background: In Stockholm, a first responder system and a Public Access Defibrillation (PAD) program has been implemented. Additionally, the number of "unregulated" public Automated External Defibrillators (AEDs) sold "over-the-counter" has increased. The aim of this study was to evaluate the impact on survival from different defibrillation strategies in cases of out-of-hospital cardiac arrest (OHCA) available for PAD.

Design: Retrospective study of all OHCAs in Stockholm, 2006-2012. Witnessed OHCAs occurring outside home with cardiac origin and ventricular fibrillation were considered subjects for PAD. The sites within the PAD program increased from 60 to 135 while the number of unregulated AEDs outside the PAD program increased from 178 to 5016. Of 6532 OHCAs, 7% (n = 474) were defined as subjects for PAD. Of these, 69% (n = 326) were defibrillated by the EMS, 11% (n = 53) by first responders and 16% (n =7 4) by public AEDs. Survival to one month was 31% (n = 101) for cases defibrillated by the EMS, 42% (n = 22) when defibrillated by first responders and 70% (n = 52) when defibrillated by a public AED. The AEDs within the PAD program constituted 2.6% of all public AEDs and were used in 28% (n = 21) of cases when a public AED was used.

Conclusions: In OHCAs available for PAD, 70% of patients survived if a public AED was used. Both the structured AED program as well as the spread of unregulated AEDs was associated with very high survival rates, but the structured approach was more efficient in relation to the number of AEDs used.