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Any people who suffer cardiac arrest and would otherwise die can
be saved if ordinary people are trained to use defibrillators to shock them back to
life, researchers are reporting today. In two studies, one conducted at casinos and the other on
airliners, survival rates were 53 percent and 40 percent for people who had cardiac
arrest and who were treated almost immediately with portable defibrillators, a
smaller version of the electrical paddles used in emergency rooms. Those survival rates are far greater than overall rates in the
United States, which are dismally low, 2 percent to 5 percent, because most victims
are not defibrillated fast enough. About 225,000 Americans a year suffer cardiac
arrest. Ideally, the shock to the chest should be given within three
minutes of the victim's collapse and is unlikely to work after ten minutes. Each
minute of delay drops the odds of survival by 7 percent to 10 percent. Defibrillation
is the only effective treatment of ventricular fibrillation. The two new studies, which appear in the New England Journal of
Medicine, reflect a larger trend in the United States to train lay people to use
portable defibrillators and make the devices available in large workplaces and public
places like sports stadiums, train and ferry terminals, airports, amusement parks,
health clubs, community and senior citizen centers and shopping malls. The drugstore chain C.V.S. has begun offering defibrillators on
its Web site by prescription for about $3,000, for people at risk of cardiac arrest. A rule adopted by the Federal Aviation Administration that took
effect in September gave airlines three years to train flight attendants and put
defibrillators on all planes that can carry at least 30 passengers and one attendant.
American Airlines has defibrillators on all its flights, and most other airlines in
the nation have begun including them, as have some foreign airlines. Portable defibrillators weigh four to seven pounds and cost $2,500
to $4,000. Lay people can be taught to use them in five or six hours. The American Heart Association estimates that if the national
survival rate for cardiac arrest victims could be increased to 20 percent, 50,000
lives would be saved. The people in the studies were treated with a type of portable
defibrillator that first monitored the heart and then shocked it only if the machine
detected a particular abnormal rhythm, ventricular fibrillation, which accounts for
80 percent of all cases of cardiac arrest. In that condition, the main pumping
chamber of the heart quivers instead of beats and loses the ability to pump blood.
People in that condition have no heartbeat or breathing but do have some electrical
activity in their hearts. In some cases, ventricular fibrillation is brought on by
underlying heart disease, and in some cases the cause in unknown. Ventricular
fibrillation causes sudden death and is different from the more common type of heart
attack, myocardial infarction, in which blockages in coronary arteries choke off
blood supply to the heart. People with myocardial infarction would not be helped and
instead would be harmed by defibrillation. Portable defibrillators, sometimes described as
"idiot-proof," will not deliver a shock for any condition other than
ventricular fibrillation, because shocking a healthy person or someone with another
type of heart problem could be dangerous or even fatal. The machine will not fire if
a patient's heart has no electrical activity, because a shock will not restart such a
heart. The machines have recorded voices that talk users through the
steps of defibrillation and cardiopulmonary resuscitation. A study last year showed
that sixth-grade students could follow the directions and took only 27 seconds longer
to do so than emergency medical technicians or paramedics. The idea of equipping casinos with defibrillators came from
Richard Hardman, an author of one study and coordinator of emergency medical services
in Clark County, Nev., which includes Las Vegas. Mr. Hardman said that in 1995, his
department noticed that the county had a higher rate of cardiac arrests than other
areas with similar populations and that more than 60 percent occurred in hotel
casinos. Dr. Terence Valenzuela, one of authors and a professor of
emergency medicine at the University of Arizona, said: "I don't think there's
anything dangerous to your health about casinos. There are just a lot of high-risk
people there. They're older; there are a lot of smokers; and they congregate there
for long periods of time." Hoping to improve survival, Mr. Hardman and his colleagues
approached the casinos about defibrillators. Initially, he said, they resisted,
mistakenly fearing that people could be harmed by defibrillators and that the casinos
would be liable. "But defibrillators are applied to somebody who's essentially
dead, with no pulse and no breathing," Mr. Hardman said. "You really can't
make that condition any worse." Once that was understood, the casinos agreed to have their
security guards trained. The first to try it was Boyd Properties, which owns the
Stardust, the El Dorado, the California and other casinos in Las Vegas and elsewhere. The officers, already certified in CPR, then had five to six hours
of training to use defibrillators, which were brought into the casinos in March 1997. The first person saved, on July 1, 1997, was a man in his 70's who
collapsed at a slot machine in a Boyd casino. He was staying at a hotel that didn't
have a defibrillator. "His wife observed the defibrillator being used and was made
aware that if it had happened where they were staying, he probably wouldn't have
survived," Mr. Hardman said, adding that the wife moved into the Boyd hotel. The man recovered; the idea caught on; and more than 70 casinos,
most in Nevada, now have defibrillators, Mr. Hardman said. The study included 105
people who collapsed and were defibrillated between March 1997 and October 1999; 56
recovered. None had brain damage, which can follow cardiac arrest if the heart was
not restarted quickly and the brain was deprived of oxygen. Nevada, New York and at least a dozen other states have passed
laws to exempt people from liability when they use a defibrillator to save someone. A surveillance tape from one of the casinos, provided by Dr.
Valenzuela, shows a man collapsing at a roulette table. Guards rush to him, remove
his shirt and frantically shave his chest, while nearby casino patrons gamble on,
barely looking away from their cards or dice. The guards slap two large adhesive
patches, containing the defibrillator's electrodes, onto the man's chest. Within
seconds, the defibrillator commands them to deliver a shock. They move clear of him
to avoid being shocked, one presses a button, and the man's body jerks as the
defibrillator fires. The victim's heart rate and breathing are restored, and within
minutes he is sitting up and talking. An ambulance team wheels him out on a
stretcher, past other gamblers, most still oblivious of the man who has essentially
died and been revived in their midst. The second study, by researchers at the University of Texas
Southwestern Medical Center at Dallas, examined the use of defibrillators by American
Airlines, which began putting them on planes in March 1997. The airline now includes
them on all flights and has trained its 24,000 flight attendants to use them. Six of fifteen passengers who needed shocks between June 1997 and July 1999 survived.
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