Doctors have had the technology for several years for therapeutic hypothermia. An increase of using the procedure though has only taken off in the past 18 months. There are risks involved when the body core temperature is reduced. It requires a team of experts to control all the factors.
"It's not as simple as just cooling somebody's body temperature down — it requires intense training and action by nursing staff, cardiologists, respiratory care providers and intensive care specialists," said Dr. John McPherson, medical director of the Cardiovascular Intensive Care Unit at Vanderbilt.
"We were like all medical centers in that we knew this was the right thing to do, but the experience was limited nationwide on how to do this appropriately."
Starting this year New York City heart attack victims will only be transported to hospitals that use the cooling method. That is already in place in Seattle, Boston and Miami.
When a person suffers a cardiac arrest their heart's electrical system goes on the fritz. The heartbeat aburtly stops during this process. When the heart beat is not operating correctly or stops completely oxygen rich blood is not being pumped into the brain causing cells to die. Often those who survive the heart attack itself are left with lasting brain injuries which run the gamut.
The patient is given medicine to paralyze them to prevent shivering. After the patient is immobile specialized pads, blankets and wraps cover the body except for the face. The body is cooled to about 89 degrees Fahrenheit in about six hours.
After 24 hours the patient who has been cooled begins the warming process. The body gains about a half a degree increase in temperature an hour.
"A lot of permanent brain injury does not happen at the exact moment the brain is deprived of oxygen — a lot of that brain injury occurs within the first 24 hours after the event," McPherson said. "Cooling the body temperature down stabilizes some of those brain cells to prevent that cell death and prevents ongoing injury that can occur from inflammation in the first 24 hours after brain injury."
The process can be the cause of serious risks including an increased rate of infections. Changes to the blood sugar, fluid balance, blood pressure, heart rhythms and abnormal clotting are all concerns with the cooling and rewarming process.
Not every patient is eligible for the procedure. A patient's pulse has to be regained first and they have to have a stable starting blood pressure.
"We're learning more and more about resuscitating patients after cardiac arrest and this is an important part in their treatment," McPherson said. "I think, going forward, you're going to see more sophisticated ways of how to improve heart and brain functions in these patients and I think this is a great first step."
The procedure is a stable for heart attack victims at Saint Michael's Hospital in Toronto. The team works like a well oiled machine as the cooling process begins. The patient is constantly monitored during the 24 hours to make sure changes are taken care of quickly.
While it can not stop brain injuries that have already taken place it does give the brain a fighting chance at recovery.