This is despite several campaigns to increase the numbers of these life-saving devices in public places, and the acknowledgement of the importance of their role in the English government’s Cardiovascular Disease Outcomes Strategy, published last March.
Professor Charles Deakin, of the NIHR Southampton Respiratory Biomedical Research Unit, University of Southampton, and is also a consultant in Cardiac Anaesthesia and Intensive Care at Southampton General Hospital, was one of the leaders of the study.
He comments: “Survival from the 30,000 annual cardiac arrests where resuscitation is attempted remains disappointingly poor, with survival rates of only seven per cent. Bystander CPR and early defibrillation with public access defibrillators (PADs) have the potential to increase survival three-fold and we were therefore interested to see how often this intervention was available to patients prior to ambulance arrival.
“Despite efforts by the Department of Health and the British Heart Foundation to promoted and distribute PADs, together with additional PADs made available by community groups, we found that many key locations remain devoid of a PAD, such as GP surgeries, railway stations, gyms. A PAD was available in only four per cent of confirmed cardiac arrests and even then, only half of these patients had a PAD successfully attached. The lack of PADs, knowledge of their location and confidence to use them is significantly limiting the successful resuscitation of patients suffering out-of-hospital cardiac arrest. More needs to be done to strengthen these early links in the chain of survival.”
External defibrillators can be used to shock an arrested heart back into rhythm before the arrival of an ambulance. They don’t require any specialist expertise, and can be used by anyone—which is particularly important, as the evidence shows they can triple the chances of survival.
The study, which was also carried out by South Central Ambulance Service and is published in the journal Heart, wanted to find out how available external defibrillators are, given the push for their deployment in public places, such as shopping centres and train stations over the past decade.
Researchers concentrated on one typical county of England—Hampshire—which has a mix of rural and urban settlements, covering an area of 1400 square miles, with a population of around 1.76 million, 12% of whom are aged over 70.
They reviewed all calls made to the South Central Ambulance Service between September 2011 and August 2012 following a heart attack. For all emergency calls made from locations other than a person’s home, the service specifically asks whether the caller can access a defibrillator, and if so, instructions are given in how to use it.
During the study period, 1035 calls were made following confirmed cardiac arrests away from a hospital, equivalent to one for every 600 members of the public each year.
For 44 of these incidents (4.25%), in 34 different locations, the caller was able to access an external defibrillator, but attach it to the victim in less than half the cases (18, 41%) before the arrival of the emergency services.
This gives an overall deployment rate of just 1.74% of all cardiac arrests recorded, which the authors describe as “disappointingly low.”
Across the county, 673 external defibrillators were located in 278 places as of October 2012, including in all large shopping centres. But only just over one in 10 nursing homes, around one in 20 train stations, and a similar proportion of community centres/village halls had these devices.
Professor Deakin and his research colleagues acknowledge that they did not investigate the availability of public defibrillators across the UK, but suggest that their findings “would probably be similar elsewhere.”
They add: “The poor survival rates in [out of hospital] cardiac arrest are in part related to delays in defibrillation. More defibrillators are required in public areas and more education is needed to give bystanders the confidence to use the [device] when it is available.”
University of Southampton