Automated external defibrillators may not be the best choice for hospital… (Alexander Gallardo / Los…)
Hospitals around the country have been spending millions of dollars to buy automated defibrillators to save the lives of more patients who go into sudden cardiac arrest. The purchases were spurred by a 2000 recommendation from an American Heart Assn. committee that said the equipment would bring patients speedier emergency medical help.
But today the costly investment increasingly seems to have been a mistake. Research suggests that the new gear, now found in nearly all hospitals, saves fewer lives than the old, lower-tech defibrillators. By one estimate, the switch to automated defibrillators means that close to 1,000 more hospital patients die of cardiac arrest every year in the U.S.
A review of the decision that prompted the switch reveals that the pivotal recommendation was made without data to answer a crucial question: Did the new devices, when used in hospitals, produce better results than the old equipment?
Defibrillators use pads placed on a patient's chest to deliver a shock that can restore a heart's normal rhythm. The automated devices were endorsed largely on the theory that they would improve response times because even less-skilled hospital staffers could operate them.
"I think they jumped the gun," said Dr. Steven Nissen, chair of cardiovascular medicine at the Cleveland Clinic in Ohio.
Or, as Dr. Roger White, a Mayo Clinic anesthesiologist in Rochester, Minn., who was on a subcommittee that provided defibrillator advice to the AHA, put it: "What we thought would work hasn't worked so far."
Upgrading hospital defibrillators made sense — in theory. Members of the heart association committee were alarmed about the amount of time it took at many hospitals to provide shocks to patients who went into cardiac arrest. A big part of the problem was that, although critical-care nurses typically knew how to work the traditional defibrillators, many nurses in general wards did not.
The new equipment, which provides step-by-step voice instructions, figured to be easier for more people to operate.
And the cost was modest, by hospital equipment standards. The basic models begin at around $1,600. The dual-mode equipment — which can run automated or manually, like the older-generation devices — can cost more than $10,000.
Yet in crafting the recommendation, the committee acknowledged that research had not yet proved that the new devices improved survival rates for hospital patients. Instead, committee members said, they relied mainly on evidence that the simpler version of the new devices — often known as automated external defibrillators, or AEDs — saved lives in public settings such as airports. The committee even scolded hospital administrators for failing to stock up on the new defibrillators.
Purchases of the devices zoomed after the guidelines were released. U.S. hospitals bought close to 100,000 of the basic automated models from 2000 to 2010, according to the consulting firm Frost & Sullivan.
Soon after the recommendation came out, however, product quality flaws began to emerge. In many instances, the devices failed to turn on, or they turned off unexpectedly. Manufacturers have recalled tens of thousands of the devices.
An assessment published in August in the Annals of Emergency Medicine found that more than 1,000 cardiac arrest deaths from 1993 to 2008 were connected to the failure of the automated devices in hospitals and other settings.
An industry group, the Advanced Medical Technology Assn., said that companies are working with the U.S. Food and Drug Administration to improve the safety of the devices.
For hospitals, however, an even worse problem is that automated defibrillators are poorly suited for many of their patients. That issue was spotlighted by Dr. Paul S. Chan, a cardiologist at St. Luke's Health System in Kansas City, Mo.
Cardiac arrest causes the heart to abruptly lose function. In most people, the cure is an electrical shock, or defibrillation. But hospital patients who suffer cardiac arrest tend to be sicker than the average victim and may have complex medical problems that are interfering with their heart, Chan said. These patients are more apt to suffer "non-shockable" cardiac arrest — episodes that can't be fixed with the electrical shock delivered by a defibrillator.
Chan led a study of 11,695 patients in 204 hospitals who suffered cardiac arrest from 2000 to 2008. His research, published last year in the Journal of the American Medical Assn., showed that 82% of those arrests were non-shockable.
To treat those patients, a defibrillator still may be needed to provide readings on how a patient is responding to CPR. Ordinarily, CPR is applied and then periodically interrupted so that the defibrillators can provide those crucial readings.