A Portable CPR Machine

Dec. 2, 2003 -- About 600,000 people in the United States will suffer a heart attack this year and most of them will not survive the life-threatening experience.

"The long and short of it is, there are 460,000 people that die each year from sudden cardiac arrest," says Dr. Henry R. Halperin, a cardiologist and professor of medicine and biomedical engineering at Johns Hopkins University in Baltimore, Md. "Survival is only 5 to 10 percent and that's pretty bad."

To combat the dismal survival rate, experts are pursuing a variety of solutions — including new devices that can automatically provide critical first aid to victims.

The latest tool being developed is called AutoPulse.

A Bootstrap Beater

Produced by Revivant Corp. in Sunnyvale, Calif., the device is designed to automatically perform cardio pulmonary resuscitation, or CPR, on heart attack victims. And how AutoPulse works is fairly simple.

The device consists of a 2-inch thick board that contains a motor, rechargeable batteries, and an 8-inch wide belt. The board is placed underneath a heart attack victim and the belt is strapped across the victim's chest.

Once the device is turned on, the motor alternatively retracts and plays out the belt, producing the same CPR chest compressions that would be performed by emergency rescue personnel or hospital staff.

Steve Bystrom, president and chief executive officer of Revivant, acknowledges that the AutoPulse isn't the first mechanical CPR devices.

Another company had previously developed a CPR machine that featured an inflatable vest to compress the victim's chest. But that unit was far from perfect for use outside of the hospital since it weighed about 125 pounds and required an electrical outlet for power.

"We studied what the vest did and removed the components that were inefficient," says Bystrom.

By replacing the pneumatic system with an electromechanical setup, for example, the AutoPulse weighs a more manageable 20 pounds, but still produces up to 80 compressions per minute. It can also operate for 30 minutes to 60 minutes on a single set of rechargeable batteries.

Porcine Proof?

And Halperin, one of Revivant's scientific consultants and investors, says AutoPulse's design may provide other benefits.

"Standard CPR is performed over one part of the person's chest," says Halperin. "What [AutoPulse] does is spread a greater force over the whole chest but doesn't break the [victim's] chest."

And Halperin believes that such features may make AutoPulse more efficient than standard CPR. In recent lab tests involving 20 pigs that were induced into cardiac arrest, Halperin says the AutoPulse produced blood flow that was four times better than standard CPR methods.

The results were presented to the American Heart Association at a Nov. 19 meeting in Chicago and are still under review. But could such a device actually save more heart attack patients?

The (Research) Beat Goes On

"It looks fascinating, but there have not been large clinical trials to prove [its beneficial] outcome," says Dr. Vinay Nadkarni, chairman of the emergency cardio-vascular care committee of the AHA. "For it to be a breakthrough [development], we expect to see improved survival rates in hospital admissions of cardiac patients at least."

"No one has any real-time experience in the field yet," Revivant's Bystrom admits. But that may change soon.

Since it is based on previously accepted mechanical CPR devices, AutoPulse has been recently cleared by the Food and Drug Administration for use in the U.S. And Bystrom says the company plans on beginning limited field tests in a few undisclosed hospitals later this month.