In a new five-year study, researchers from Michigan found that only two out of 47 cardiac arrests at K-12 schools occurred during sports events. In fact, as many as a third of cases happened after 5 pm and mostly in adults.

"Schools are community-gathering places, and two-thirds of our cases were adults," said Dr. Robert Swor, an emergency physician at Oakland University William Beaumont School of Medicine in Royal Oak.

His findings, based on registries and interviews with bystanders and school officials across the country, show that fewer than two out of every 1,000 cardiac arrests overall happen at K-12 schools. Sixteen of the 47 cardiac arrests at schools involved minors.

Still, Swor told Reuters Health, "these are high-profile events individually. Every time something happens in a school like this it gets a lot of community awareness."

After looking at how often cardiac arrests happen in schools, and who are the most frequent victims, Swor and his colleagues conclude more attention to emergency response capabilities and preparedness in schools is needed.

Several states require schools to have automated external defibrillators, or AEDs, on site to treat cardiac arrests. The briefcase-sized devices let non-experts check a person's heart rhythm via patches glued to the chest. If the heart is beating too fast - known as ventricular tachycardia - to pump out enough blood, or just quivering chaotically in so-called ventricular fibrillation, the AED can jolt it back to its normal rhythm.

Just last week, New Jersey Governor Chris Christie signed legislation making AEDs and cardiac emergency plans a requirement at all schools in the state.

Swor's team, whose results were published in the journal Resuscitation, was able to interview people at 30 of the 47 schools they located.

It turned out that 19 had AEDs. When the AED had been used, four out of 11 people survived until they were discharged from the hospital. When the device hadn't been used, the survival rate was two out of eight.

"It confirms that if you put the AED on you are in good shape, because we are talking about a 50-percent survival," said Dr. Myron Weisfeldt of Johns Hopkins University, who has studied AEDs but was not involved in the new work.

About 300,000 Americans suffer cardiac arrest every year and fewer than eight in 100 leave the hospital alive. AEDs, which are placed in airports and many other public areas, may save nearly 500 lives every year, according to a study by Weisfeldt and colleagues from 2010.

The devices can be bought for less than $2,000 and are easy for laypeople to use. Swor said it appeared that when they weren't used, it was often because bystanders had trouble identifying the signs of a cardiac arrest - for instance because the victim was convulsing or still gasping.

When in doubt, he added, the AED should always be used because it won't deliver any shocks unless it detects a specific heart rhythm disturbance.

Both Swor and Weisfeldt called for drills in schools to teach staff and students the signs of cardiac arrest, as well as how to give chest compressions and use an AED - and of course, call 911.

"We have fire drills, we have tornado drills," said Swor. Cardiac arrests "are not common, but they are certainly more common than a school being hit by a tornado."

Weisfeldt added that seizing the chance to teach students CPR is not only helpful while they're in school, but might pay off down the road if they ever witness a cardiac arrest.

"It's a teachable moment," he said.

SOURCE: bit.ly/S6MLMm Resuscitation, online September 20, 2012.

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