Lay people can effectively use defibrillators to save the lives of cardiac arrest victims

Dec 5 2005

The first large-scale study to see whether trained volunteers and lay people can use defibrillators to save the lives of cardiac arrest (CA) victims has concluded that their use by lay people is safe, and if the response time can be shortened to within eight minutes there is the potential to save the lives of 15 out of 100 people who collapse suddenly with CA.

Brescia in Italy – a large mixed rural and urban county with an area of more than 4,800 square kilometres and a population of well over a million – was the site for the Brescia Early Defibrillation Study (BEDS), the results of which are reported (Thursday 1 December) in the European Society of Cardiology's journal European Heart Journal.

Dr Riccardo Cappato from Policlinico San Donato, University of Milan, and colleagues from the University of Brescia and the University of Washington in Seattle, USA, initiated BEDS after Italy passed a law allowing the use of automated external defibrillators (AEDs) by non-medical personnel.

A total of 2,186 volunteers and lay people received five hours of training involving theory and practical instruction, including training in basic life support, from 14 qualified instructors. One AED was supplied for every 22,700 of the population, in addition to the existing manually operated defibrillators used by the county's 10 hospitals and in five medically equipped ambulances. The new volunteers were then organised into groups.

The study started in 2000, but for a two year period before that the team collected data to set the parameters for the study, including the numbers of CAs that happened outside of hospitals, the time it took for help to arrive and the number of patients who survived free of any neurological impairment one year after their heart attack. Further data were collected during a six-month pilot study. The historical cohort of 692 acted as comparisons for the prospective study, which involved 702 similar patients between 2000 and 2002.

Dr Cappato, who is Professor of Electrophysiology and Chief of the Arrhythmia and Electrophysiology Center in Milan, said: "Overall, we found that three out of a hundred patients in the prospective study survived to one year without any neurological problems, compared with under one out of a hundred of the earlier comparison group, even though the time from dispatching help to arriving with the patient was similar.

"There was an increase in survival for patients in both urban and rural areas, although it was significantly larger in the city than the countryside due to the shorter response time and larger number of defibrillators available. In the urban areas, survival rose from just under one and half persons per hundred in the earlier group to four per 100 in the study. In the rural areas it rose from one per two hundred in the earlier group to two and a half per hundred in the study. When you look at the relative gains though, as opposed to the absolute values, there was more benefit for the rural areas.

"However, there was a more than three times higher incidence of defibrillator teams being dispatched to CAs in urban areas (0.7 per 1,000 per year) than in the countryside (0.2 per 1,000 per year). This appears either to be mainly due to worse access in the country because of a higher incidence of CAs happening with no witnesses around, or a lower tendency for witnesses in rural areas to call out help."

For every quality adjusted life year (QALY) saved during the study it cost less than 24,000 Euro (around 39,000 Euro during the start-up phase). The set-up costs were over one million Euro and the running costs once the system was established were around 681,000 Euro.

Dr Cappato said that the study had proved that defibrillators can easily and safely be exclusively operated by lay people. "This is an unprecedented finding and we hope that our study will serve as a benchmark for more systematic approaches in the future."

Operating the defibrillators did not require lots of training – only five hours, plus a three hour refresher course every six months. There were no problems or complications involving the operators in around 1,000 interventions.

It was though, he said, too early to expect national healthcare systems to be interested in supporting an ELPIS (Emergency Lay Person-Integrated Service).

"In our study, over three-quarters of the victims whose collapse was witnessed received defibrillation more than eight minutes after cardiac arrest. National standards require 90% of victims to be reached within eight minutes. Even so, it is worth noting that patients who received defibrillation later than the eight-minute threshold, accounted for a third of the those who survived at one year free of any neurological problems."

Dr Cappato said this finding outlined the need both for strenuous resuscitation efforts to be made with current technology even past the eight-minute point and for re-evaluation of early defibrillation programmes.

Dr Antonio Curnis, Chief of Electrophysiology at the Civil Hospital in Brescia and co-author of the study, said: "To make ELPIS widely feasible, we need to prove larger survival rates are achievable. I think it's possible. The key lies in reducing the time between the person's collapse and the arrival of the rescue team. If we can get that down to within eight minutes we could have 15% of CA patients surviving long-term, free of neurological damage. That is a huge number of lives given the incidence of CA in a population.

"It will need better organisation of the logistics and manpower, and co-operation among people with different professional specialties. It's difficult, but it is possible."