Public access defibrillation is giving access to lay persons to administer defibrillation for out-of-hospital cardiac arrest immediately using automated external defibrillator (AED). Several studies have shown that a public access defibrillation program improves the survival rate in patients with out of hospital cardiac arrest .
A prospective trial was reported in 2004 in which more than 19000 volunteer responders participated . Lay volunteers were trained in cardiopulmonary resuscitation (CPR). The study had two groups, one in which only CPR was given while in the other group CPR and AED were used. 70% of the cardiac arrests were in public locations and 72% were witnessed cardiac arrests. No inappropriate shocks were delivered. There were 30 survivors to hospital discharge among 128 cardiac arrests in the CPR plus AED group. In the CPR only group, 15 among 107 survived to hospital discharge. Functional status at hospital discharge did not differ between the two groups. This study showed that trained lay persons can use AEDs safely and effectively.
Nationwide dissemination of public access AEDs in Japan was reported in 2010 . 312,319 adults who had out-of-hospital cardiac arrest were included in the study. 12,631 of these patients had ventricular fibrillation and cardiac origin witnessed cardiac arrest. 462 were administered shocks by lay persons with public access AEDs. Though this gave an average percentage of 3.7%, the percentage increased from 1.2% to 6.2% as the number of public access AEDs increased. 14.4% of those with witness cardiac origin cardiac arrest were alive at 1 month with minimal neurological deficit. Among those who received shocks from public access AEDs, 31.6% were alive at 1 month with minimal neurological deficit. The number of AEDs were 4 or more per square kilometer of inhabited area towards the end of the study period, while it was less than 1 initially.
Another study published in 2019 reported on 1,299,784 patients with out-of-hospital cardiac arrest from a prospective nationwide Japanese registry . There were 28,019 patients with witnessed cardiac arrest and shockable heart rhythm who had received bystander CPR. Proportion of patients with a favourable neurological outcome was significantly higher in those who received public access defibrillation than those who did not. 30 day survival was also higher in those who received public access defibrillation.
These studies support the wide dissemination of public access defibrillation for improving survival in out-of-hospital cardiac arrest. Main limitation will be the cost of equipment in regions with poor economic resources.
Kitamura T, Iwami T, Kawamura T, Nagao K, Tanaka H, Hiraide A; Implementation Working Group for the All-Japan Utstein Registry of the Fire and Disaster Management Agency. Nationwide public-access defibrillation in Japan. N Engl J Med. 2010 Mar 18;362(11):994-1004.