By Martin E. Comas
The Orlando Sentinel
TAVARES, Fla. — Local paramedics have started giving heart-attack patients the big chill to thwart brain damage and save lives.
In a relatively new technique that is being used by a growing number of hospitals and emergency responders in the United States, Lake-Sumter Emergency Medical Services recently began inducing mild hypothermia — or lowering the body temperature to about 91.4 degrees Fahrenheit — in cardiac-arrest patients to reduce the onslaught of brain damage that occurs moments after the heart has suddenly stopped beating.
“There is a significant difference in mortality in people [cardiac-arrest patients] who are cooled and those who are not,” Dr. Paul Banerjee, medical director for Lake-Sumter EMS, said this week.
The cooling technique essentially involves putting people on ice.
After suffering a heart attack, the patient is injected by paramedics with a saline solution at about 39.2 degrees Fahrenheit. Emergency workers also cover the patient’s head and arm pits with ice packs before delivering them to hospital.
Hospital workers then continue lowering the person’s temperature to about 91.4 degrees Fahrenheit — or 33 degrees Celsius — and maintaining it at that level for 24 hours.
‘Lessening the damage’
The cooling slows the body’s metabolism and gives the brain time to regroup after the trauma of losing normal blood flow and the buildup of damaging toxins, Banerjee said. It’s like putting the brain in suspended animation.
“By diminishing the amount of toxins that are released into the brain after a cardiac arrest, you provide them with a better chance to the same quality of life” they had before the heart attack, he said. It gives people a better chance of avoiding severe disability.
The patient is kept in an induced coma and then gradually warmed back to normal body temperature — or about 98.6 degrees Fahrenheit — over eight to 12 hours. Sedatives are used to prevent shivering, and the patient is gradually weaned off the paralysis and sedation.
Lake-Sumter EMS is also using the cooling technique to treat spinal-cord-injury patients and reducing the chances of permanent paralysis.
“By cooling them [spinal-cord injuries] you reduce the inflammatory cascade, and hopefully you have better chances of lessening the damage,” Banerjee said. “And they may have better chances of walking out of the hospital.”
Athlete’s example
Banerjee used as an example Kevin Everett, a professional football player for the Buffalo Bills whose spine was fractured and dislocated during a 2007 game. Everett, who had complete paralysis and lack of sensation, was immediately cooled and then rewarmed three days after surgery. Nearly four months later, he was able to walk again.
Each of Lake-Sumter EMS’ 28 ambulances is now equipped with special coolers that keep the saline solution and packs chilled. Local fire departments soon will have the coolers. Each cooler costs about $500 each.
Although its gaining use in the United States, the cooling technique has been commonly used in Europe.
But the cooling down can’t be used on everyone. It’s excluded for people with bleeding disorders, dialysis patients or someone who has had major surgery within the past 14 days.
‘Pretty exciting’
Since starting the technique on Sept. 8, Lake-Sumter EMS officials have used it on two cardiac patients and one spinal-cord injury patient, according to Jim Judge, the agency’s executive director.
EMS officials pointed out that in 2007-08, the agency treated 245 cardiac-arrest patients. Of those, 57 made it to the hospital alive and only three survived.
Around the country, about 1,000 people suffer a heart attack every day. Of those, only 10 percent — or 100 patients — survive.
“We think it’s pretty exciting,” Judge said about using the new cooling technique. “We think it’s going to enhance our cardiac-arrest survival rate. . . . Our goal is to increase the number of patients who walk out of the hospital after a cardiac arrest and lead normal lives.”
Copyright 2009 Sentinel Communications Co.