The lesson at King Liholiho Elementary School in Kaimukí Tuesday afternoon was saving lives made simple as 1-2-3.

The students were three dozen Liholiho teachers and staff members who stayed after school to find out, to their surprise, that a heart attack and a cardiac arrest are not only different, but they aren't even close.

"One is a plumbing problem (the heart attack), and one is an electrical problem (cardiac arrest)," said Pamela Foster, a veteran emergency-room nurse and president of the AED Institute of America, which promotes community awareness of automated external defibrillators, or AEDs.

With a heart attack, there are symptoms such as chest pain, nausea and shortness of breath, for example, Foster told the gathering. With cardiac arrest, there are no symptoms, no pains and especially no breath, or even a heartbeat.

"With cardiac arrest, you're dead," said Foster, who had come to the school library with the group Hearts of the Islands Volunteers Hawaii, which conducts free CPR and AED training classes.

Foster and her colleagues were also there to present Liholiho Elementary with a $2,000 AED gift from Rachel Moyer, a Pennsylvania mother whose 15-year-old son, Greg, died in 2000 after a basketball game. Rachel Moyer has since donated more than $1 million worth of defibrillators to schools across the nation.

The Liholiho gift — Hawaii's second from Moyer — was being made in the memory of Kristin Akemi Maekawa Claudi, who did her student teaching at Liholiho school, and whose mom, Sharon Maekawa, taught at the school for 18 years before retiring.

Sharon and Stan Maekawa, Kristin's parents, along with Kristin's husband, Valter Claudi, were also in the library for the presentation.

Sharon Maekawa spoke about how her ever-healthy and energetic 28-year-old daughter had two passions: "Everything Italian" (she met her husband while living in Rome) and teaching special- needs children after returning to Hawaii with Valter.

"Everything was falling into place — life was great, " said Maekawa of Kristin. On May 27, without warning, "everything changed" when Kristin died suddenly of cardiac arrest.

Now, Sharon Maekawa assists folks like Foster, devoting her time to helping others "know what a cardiac arrest is and what to do about it."

They said these are the crucial steps:

• Call 911 immediately (do not call a relative or friend; time is of the essence, and every second counts).

• Start "hands only CPR."

• Use an AED if one is available.

What to do about cardiac arrest has been greatly simplified by recent research and developments that eliminate the three main reasons people why people are afraid to do CPR: fear of doing it wrong and harming the victim; fear of harming themselves by doing mouth-to-mouth breaths and catching a disease; and fear of getting sued.

Fears one and two can be scratched by simply doing what's known as "hands only CPR" — which, as the name implies, is done by placing one hand on the victim's chest on the nipple line, putting the other hand on top, interlocking the fingers, and pushing downward forcefully about 100 times a minute. No breaths are necessary.

Researchers now know there's enough oxygen in a person's blood to feed the brain for a few precious minutes after cardiac arrest. All that's required is for somebody to keep the blood pumping until the paramedics arrive.

Fear of lawsuits, in Hawaii and many other states, is eliminated by Good Samaritan laws that gives immunity from all liability to people trying to help a cardiac arrest victim.

"You can't harm anyone who is not breathing and has no heartbeat," Foster said. "You can only help them."

Modern AEDs are increasingly available at government offices, airports, shopping centers, restaurants, schools and universities and other locations where people congregate.

They've been made simple and easy to use, Foster told the gathering. How simple? Open the lid, push the lighted button, and follow the audible instructions that are, says Foster, simple enough for a fourth-grader to understand.

"The machine is foolproof. You just have to use it," said Foster, who demonstrated the machine on herself and even instructed one reluctant teacher to press the shock button, which, when it was finally pushed, did nothing.

"I trust the machine because I know it won't shock me unless it senses a shockable rhythm," said Foster, who pointed out that cardiac arrest is the leading cause of death in the United States.

"And it won't sense a shockable rhythm in me because I'm alive — I've got a heartbeat."