by Justin Brown, FF/EMT-P
7/28/2009

NEW YORK (Reuters Health) - Placing portable defibrillators in schools and other busy public spaces could get timely, possibly life-saving, treatment to many people whose hearts stop beating, according to two studies published Monday.

Most cases of cardiac arrest occur when the heart goes into ventricular fibrillation, a heart-rhythm disturbance in which the heart begins to quiver chaotically and can no longer pump blood around the body.

An electrical shock from a defibrillator can restore the heart's normal rhythm and reverse cardiac arrest. In recent years, portable, layperson-friendly versions of the devices, called automated external defibrillators (AEDs), have been placed in a growing number of public places.

AEDs automatically analyze the heart's rhythm and, if needed, instruct the user to deliver a shock.

In one of the new studies, researchers found that at 1,710 U.S. high schools with AEDs on site, nearly two-thirds of cardiac arrest victims survived. That compares with a typical survival rate of only about 5 percent when cardiac arrest occurs outside of a hospital.

In the second study, Danish researchers found that following guidelines from the American Heart Association (AHA) on placement of AEDs in public places could get prompt treatment to nearly 70 percent of cardiac arrests that occur in public.

The studies, both published in the AHA journal Circulation, suggest that strategically placed AEDs could improve the dismal survival rates from cardiac arrest.

The findings from the high school study are "good news," according to lead researcher Dr. Jonathan A. Drezner, because while rare -- the study found that it happened to about 4 in 100,000 student athletes per year -- cardiac arrest is the leading cause of death in young athletes.

AEDs can also be life-saving for adults on school grounds. Of the 36 cardiac arrests in the high school study, 22 occurred in adults. Fourteen of those victims survived, as did nine of 14 student athletes.

"Placing AEDs in schools in schools is a strategic way to protect children, young athletes and adults from a catastrophic outcome if they suffer an unexpected cardiac arrest," Drezner, an associate professor at the University of Washington in Seattle, told Reuters Health.

The Danish study looked at the potential effectiveness of following two different guidelines on public placement of AEDs: the AHA guidelines, which recommend the devices for places that see at least one cardiac arrest every five years, and European guidelines that call for AEDs in public areas that see one cardiac arrest every two years.

The AHA advice, researchers estimate, would have covered 67 percent of cardiac arrests that occurred in Copenhagen over 10 years. The European guidance would have covered just 20 percent.

Still, wider AED placement is not enough on its own, according to lead researcher Dr. Fredrik Folke, of Gentofte University Hospital in Denmark. It's still up to bystanders who witness a person collapse to quickly get help -- calling 911 and alerting personnel who will know where the AED is, and how to use it.

Performing immediate CPR also remains vital, Folke told Reuters Health, since a victim's chances of survival drop 10 percent for each minute defibrillation is delayed; CPR improves those odds.

Similarly, schools need to have an overall emergency response plan to cardiac arrest, Drezner's team points out. That includes training all staff in the signs of cardiac arrest and the location of the school AED, Drezner said. He added that all coaches and physical education teachers should know how to perform CPR and use the AED. In his study, 83 percent of schools had an emergency response plan, but only 40 percent reviewed and practiced it at least once a year.

SOURCE: Circulation: Journal of the American Heart Association, August 11, 2009. 

The Town of Holliston has AEDs placed in The Senior Center, Elementary School, Middle School, High School, and The Town Hall in addition to police cars and ambulances/fire vehicls. 

SAVE A LIFE!  The Holliston Fire Department offers FREE (only cost is $5 for completion card) CPR training to the community. Visit www.hollistonfire.com/CPR for more information.

Justin Brown, EMT-P