FRIDAY, May 18 (HealthScout) -- When seconds count in a sudden cardiac emergency, the police reach the scene about two minutes faster than paramedics, says a new study. And when they carry the machines that can shock a racing heart back to normal rhythms, a victim's chances of living double, the study adds.
"What it means is survival," says Dr. Robert J. Myerburg, director of the division of cardiology at the University of Miami School of Medicine. He presented his findings recently at the 22nd annual meeting of the North American Society of Pacing and Electrophysiology in Boston.Sudden cardiac arrest is the leading cause of death for Americans, killing about 350,000 each year, according to the American Heart Association. It frequently happens without warning, and a victim can die within the space of 10 minutes without treatment. About half of these attacks are caused by ventricular fibrillation, which is irregular heart rhythm. A normal heartbeat, 70 or so beats per minute, can spike up to a rate in the 300s. Only about 1 out of 20 people survive if they have an arrest outside of a hospital; in some cities only 1 out of 100 survive.
In Myerburg's study, every police car in Miami-Dade County was equipped with an automatic external defibrillator (AED) for five months in 1999. All officers were trained to use the device, which is mainly self-operating, according to Myerburg. Of the 273 emergency calls for heart problems fielded during that time, the police response time to get to the scene averaged 5.6 minutes. In 1998, by contrast, EMS personnel averaged 7.7 minutes to respond to each of 242 calls.
The study also found that, during those five months, the police got to the scene ahead of EMS in approximately three out of every four cases.
"Police are already on the road; police are already out in the community," Myerburg says. Paramedics, whether from the fire department or elsewhere, start from a central location, which could be far from the scene, and time is lost. "They have to get dressed, get mobilized," Myerburg says.
So what do those few minutes mean? When the first responder shocked the heart during the study period, 18 percent of the 109 heart patients survived. In the year before the study, when only the fire department's EMS used defibrillators, 9.6 percent of the 94 victims survived.
A similar study from the Mayo Clinic showed that those who survived a cardiac arrest had waited, on average, for 5.6 minutes for police or EMS personnel to respond; those who died had waited an average of 6.5 minutes.
"It is statistically significant that those who survive received an early defibrillation," says Dr. T. Jared Bunch, an internist at the Mayo Clinic in Rochester, Minn., who also presented his findings at the meeting. "The amount of time that your body isn't able to profuse blood to the vital organs such as the brain, the kidney and the liver, that's time when these organs begin to die."
In Rochester, Minn., 54 percent of the patients who'd received emergency defibrillation by police or EMS survived. This compares with an overall city survival average of 40 percent for all those who had heart attacks.
The Florida legislature passed laws granting police protection from any lawsuits that might stem from their lifesaving efforts in cardiac arrests, Myerburg says. But the procedure itself is fairly simple. The officer puts electrical pads about the size of a greeting card on a patient's chest. The pads are connected to a box that's just a little bigger than a laptop computer and weighs less than five pounds.
"And the device literally tells you, 'Don't do anything; I'm analyzing the rhythm.' And then it will say, 'It's a shockable rhythm: push the red button,' " Myerburg says. If there is no shockable rhythm, the machine will tell the offices to perform CPR while waiting for an EMT team to arrive; meanwhile, it continues to monitor the heart rate.
What To Do
Myerburg says survival rates for cardiac arrest would be higher if families and friends of victims called 911 first, before trying to help the victim. Every minute matters, he adds.
For information on defibrillation, try the National Center for Early Defibrillation, a non-profit group at the University of Pittsburgh. You can learn more, including how to choose a doctor who specializes in heart rhythm disorders, at the Cleveland Clinic.
You can also read these HealthDay stories about recent research on defibrillation.