The best way to save a cardiac arrest victim outside of a hospital is to administer cardiopulmonary resuscitation immediately, but a major study reveals that bystanders performed CPR less than a third of the time.

The study was co-authored by Dr. Dean Hedges, the new dean of the University of Hawai'i's John A. Burns School of Medicine. It shows that the chance of surviving out-of-hospital cardiac arrest is five times greater in Seattle, where CPR training is among the highest in the country, compared to Alabama, where it is the lowest.

Hedges and his fellow researchers studied more than 20,000 such cases from 10 areas in the United States and Canada from May 2006 to April 2007. Many aspects were compared, including if the patient was administered CPR, where it happened, when was 911 called, if a defibrillator was used and how long the heart stopped working.

The study appeared in Tuesday's issue of the Journal of the American Medical Association.

The study indicated that if more areas had Seattle's 16.3 percent survival rate instead of Alabama's 3 percent, 15,500 fewer people would die from cardiac arrest in North America a year.

"This study reinforced what many of us were concerned about," Hedges said today. "We have disparities in the outcome of cardiac resuscitation that can be corrected."

"The joke in the medical field is if you ever have cardiac arrest in Seattle somebody will be administering you CPR before you hit the ground," Don Weisman of the American Heart Associaton said.

"That's what this study helps show: areas where the population is more prepared to deal with cardiac arrests and it pays off," Weisman said. Hawai'i should take note that increased training can save lives, he said.

Cardiac arrest is different than a heart attack. With cardiac arrest your heart stops beating, sometimes with no warning. It's the heart's electrical system shutting down compared to a heart attack, which damages the heart muscle and is often brought on by a blockage.

Performing CPR keeps the blood flowing and the quicker a person can be revived, the better the chance for survival.

Weisman and Hedges stressed four steps called the Chain of Survival as key to saving lives.

"No. 1, call 911 and get a defibrillator on the way as soon as possible because every minute a heart stops working you can lose 10 percent of your brain function," Weisman said. "No. 2, administer CPR; No. 3, start defibrillation; No. 4, have EMS work on the patient when they arrive.

"In a lot of cases when you make that 911 call police or fire will be there within 4 to 5 minutes and an ambulance within 8 to 12 minutes," he said.

"Your greatest chance of survival is to have people around you who know CPR. … People need to realize that 70 to 80 percent of the time you're going to be administering it in your own home to a family or member."

The AED Institute has led CPR and AED training of more than 1,700 people at Honolulu International Airport. In the past two years, said the institute's Pam Foster, there have been 12 cardiac arrest cases at the airport and seven of those lives have been saved.

"It's happened in baggage claim, at the gate, on the street, it can happen anywhere," she said.