BACKGROUND: Every year, 250,000 people die from cardiac arrest, also called sudden cardiac death. It's estimated 95 percent of people who experience cardiac arrest don’t' survive it.

The most common cause of the condition -- which happens when the heart stops pumping -- is heart attack. Another common cause is an irregular heartbeat, which often goes undiagnosed.

"For a very large percentage of people who get cardiac arrest, they don't know the have heart disease and they don't have a symptom," said Lance Becker, M.D., Director of the Center for Resuscitation Science at the University of Pennsylvania in Philadelphia.

During cardiac arrest, brain death can occur in four to six minutes, and brain damage can continue for hours or days. Dr. Becker says the three techniques that can help save patients from brain death -- and thus death -- are CPR, shocks to the heart from an external defibrillator and cooling treatments, also called therapeutic hypothermia.

SURVIVING CARDIAC ARREST: Bill Bondar is one of the 5 percent of people who survive cardiac arrest. When he arrived at the emergency room, he was comatose.

"No movement, no speech, no responsiveness, and so that's a condition that we would be very worried about," Dr. Becker said.

Dr. Becker's team saved Bondar's life by bringing his body temperature down 6 degrees Fahrenheit after they restarted his heart. Doctors jump-started his body-cooling process with two liters of ice cold saline and then continued to pull his temperature down with a cooling blanket. Experts believe this kind of cooling process protects the brain by reducing the amount of oxygen that cells need to stay alive.

Building on this hypothesis, Dr. Becker is developing a technique that brings down body temperature more quickly. Called an ice particle slurry, Dr. Becker administers saline that has tiny particles of ice mixed in. The slurry is designed so that when it melts, it turns into biologically perfect, hyper-cooled saline.

"When you inject something like that ... into the vein of an animal, the temperature responds in seconds," Dr. Becker said.

THE WAY OF THE FUTURE? Experts are so confident in the benefits of therapeutic hypothermia for cardiac arrest patients that they are pushing for policy change. A New York City protocol that went into effect January 1st of this year requires city ambulances to take many cardiac arrest patients only to hospitals that use cooling therapy to reduce the chances of brain damage -- even if it means bypassing geographically closer emergency rooms. New York City, Seattle, Boston, Miami, Vienna and London have all adopted the policy.

FOR MORE INFORMATION, PLEASE CONTACT:
Center for Resuscitation Science
University of Pennsylvania
http://www.med.upenn.edu/resuscitation