More than 1,000 deaths in 15 years linked to AED failures, new research finds
When Ralph Polanec collapsed June 25 at his Washington, D.C., gym, staff members thought they could save him with a shock from their automated external defibrillator. But when they tried to turn it on, nothing happened. The device didn’t even flicker. The gym’s staff later discovered that the AED’s batteries had been removed when they lost their charge — and had never been replaced.
That battery failure might have been Polanec’s death sentence. His heart never restarted, despite CPR from a friend and later treatment from emergency responders.
His stepmother, Ruth L. Polanec, was stunned when she learned the details of his death.
“He was just 55 years old,” said the 77-year-old Mesa, Ariz., woman. “He shouldn’t have died. I was very upset that the equipment wasn’t working, because if it had been working, it might have saved him. I just felt horrible that a young man should pass away when we have so much modern equipment today. But it’s no good if it doesn’t work.”
As it turns out, battery problems are one of the leading causes of potentially deadly AED failures, according to a new study published in the Annals of Emergency Medicine.
Some 1,150 deaths were tied to AED failures over a 15-year period, and nearly one in four of those failures was caused by problems with batteries, according to researchers who pored through nearly 41,000 reports of adverse events associated with the devices.
Problems with wiring and with the pads that attach to the patient’s chest accounted for other top concerns, said Dr. Lawrence A. DeLuca, the study’s lead author and an assistant professor of emergency medicine at the University of Arizona.
AEDs seem to be ubiquitous these days, popping up everywhere from fitness clubs and apartment complexes to airports and private homes. A recent survey by the independent market research publisher Kalorama Information suggested that AEDs for home use will be booming over the next couple of years — jumping more than 17 percent over the next couple of years. An estimated 1.5 million AEDs are sold a year, based on 2009 figures, according to Kalorama's research.
DeLuca was spurred to find out about the reliability of AEDs after having one fail on him.
Device malfunction spurred study
On vacation in the summer of 2008, DeLuca was summoned to use a defibrillator on a man who'd just gone into cardiac arrest. Two other vacationing doctors had been administering CPR when DeLuca arrived.
DeLuca grabbed the AED and put the pads on man’s chest. The device started to charge — and then suddenly went dead. Though there was a second AED at the resort, nine minutes had passed by the time the man received the shock that could have brought his heart back. DeLuca still blames the batteries for the man's death.
Those extra minutes may have made all the difference. Studies show that for every minute that passes after a cardiac arrest, the likelihood the heart will be restarted drops by 7 percent to 10 percent, DeLuca said.
After scrutinizing information in the FDA database logged between 1993 and 2008, Deluca and his colleagues determined that 23.2 percent of the AED failures were due to battery/power failures, while 23.7 percent were due to problems with the pads or connectors.
Even though the report describes a host of problems, DeLuca is quick to note that AED failures appear to be rare.
“I don’t want to send the message that these devices are unsafe or that they don’t work,” DeLuca said. “Most of the time they do work — and they save lives.”
Still, he’d like to see some changes that would make the devices more dependable — such as new designs that would allow device owners to connect AEDs to manufacturers’ computers to download new software and to run checks on the devices to make sure they’re in working order.
AED failures likely under-reported
Dr. John W. Hirshfeld Jr., says he suspects far more AEDs fail than are reported. Hirshfeld served on a recent FDA advisory panel that was asked to evaluate the defibrilators.
“These types of things do happen and they occur at some level of frequency that is disturbing,” said Hirshfeld, an interventional cardiologist and a professor of medicine at the University of Pennsylvania School of Medicine.
The FDA depends on AED users — often people who have no medical training — to recognize that they should report it when the devices fail. Many probably don’t know that they’re supposed to do this, Hirshfeld said.
“These are all tragic events, where everyone is dealing with the aftermath," he added. "Their first thought is not about telling the FDA about the problem.”
Even when people do report problems to the FDA, the accounts are often so vague that it’s hard to tell what went wrong, DeLuca said. He suggested that the agency could use a standardized form to collect information. The idea, he said, is to have a simple checklist of possible reasons for the device’s failure.
If the unit powers off, for instance, people can indicate whether the problem was due to the batteries or some other cause.
Batteries typically last anywhere from three to five years, DeLuca said. Still, things can go wrong. The best advice is to check the AED regularly and look for an error message that should alert users about low batteries.
Even that doesn’t guarantee safety, however. The device that failed on DeLuca had run a self test and reported that everything was OK.
For his part, DeLuca will always be haunted by the question of whether the man at the resort would have survived with a working AED.
“I thought it was the ideal situation,” he said. “The arrest had been witnessed by two physicians who started CPR immediately. The AED passed its self test. I was kneeling down beside him within three minutes of the time the arrest started. I can’t say for sure that this person would have lived even if it had worked, but…"
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