More than 500 lives a year can be saved annually in the United States and Canada through the widespread placement of defibrillators, finds a new study that emerged out of real-life, emergency situations.
Portable defibrillators can quickly treat a sudden heart attack by analyzing a person's heart rhythm and delivering an electrical shock if needed to get the heart pumping again.
"Good Samaritans, when given access to automated defibrillators in potentially fatal emergencies, save lives," Dr. Myron Weisfeldt, a cardiologist at Johns Hopkins University in Baltimore, who worked on the study, said in a statement.
The study, conducted in 11 cities in the United States and Canada was presented at the American Heart Association meeting in Orlando, Fla. It involved an analysis of patient records from more than 10,600 incidents of cardiac arrest that were attended to by EMS (emergency medical services) workers.
Bystanders administered CPR in nearly 30 per cent of the cases and offered CPR as well as an automated defibrillator in 2.4 per cent of the cases.
Though only 259 patients had an automated external defibrillator applied by a bystander, their survival was very good. Of patients who had a bystander perform only CPR on them, just 9 per cent survived long enough to be treated and later discharged from hospital. When bystanders provided CPR and used a defibrillator to deliver a shock, survival increased to 36 per cent -- approximately four times that of CPR alone.
Even after accounting for factors such as location of the incident and EMS response time, using a defibrillator still more than doubled the likelihood of survival to hospital discharge after cardiac arrest.
If results from the original study population of 20 million are extrapolated to the general population of the United States and Canada (roughly 360 million), an estimated 522 lives could be saved.
Previous research has shown that time is critical in saving the majority of people from sudden cardiac death. Care must be provided as quickly as possible -- ideally within five minutes of a heart attack.
The findings provide strong support for making AEDs, which typically cost around $2,000 each, more widely available, Weisfeldt said.
"When you compare that to the cost of other safety measures required by law, such as seat belts in automobiles and sprinkler systems to help control fires in buildings, my own conclusion is that it's not an enormous expense," he said.
"We do many things in the name of public safety that are much more expensive than what a community-based AED program would cost."
