Advanced Technology/Induced Hypothermia

Below is a story which involves a new and innovative technology to help prevent brain damage in cardiac arrest patients. 

On a recent evening at his Sarasota home, Jim Owens went to bed as usual. During the night, he suffered sudden cardiac arrest. The 63-year-old man's heart had stopped beating effectively, unable to pump oxygenated blood to the brain. His wife called 911, and paramedics rushed Mr. Owens to Sarasota Memorial Hospital. He was resuscitated, but had slipped into a coma, at risk for serious brain damage.

In Sarasota Memorial's Intensive Care Unit, physicians and nurses employed state-of-the-art cooling technology to chill his body quickly yet precisely to 93 degrees, protecting his brain function and helping to heal damaged tissue. Sarasota Memorial currently is the only hospital in the county using this new cooling catheter.

Owens was rewarmed and woke up about 18 hours later. After thorough evaluation, it was clear he had suffered no neurological damage. Physicians soon implanted a pacemaker and defibrillator to restore his cardiac function.

While Owens, a retired sales marketing executive with Procter & Gamble, has little memory of his high-tech treatment at Sarasota Memorial, he is happy to have fully recovered from his cardiac arrest and resume his normal activities -- particularly those requiring a great deal of mental acuity.

“I knew I would be fine when I came home from the hospital, and within a short time, I was answering final Jeopardy questions correctly,” he said.

Cardiac arrest causes about 350,000 deaths in the United States, with the vast majority of victims dying before they ever get to the hospital. It occurs suddenly and brain death can occur in four to six minutes. Even after successful resuscitation, the brain can be damaged from chemical reactions that occur when the blood starts to flow again.

Recent landmark studies show that reducing the body’s temperature below normal can prevent brain damage and save lives. In fact, the American Heart Association recently recommended that medical personnel cool cardiac arrest patients. Several studies also stress the importance of avoiding fever, which can be common, difficult to control and responsible for additional brain damage in cardiac arrest victims.

“Research consistently shows that therapeutic hypothermia can lessen or prevent neurological damage from cardiac arrest and subsequent oxygen loss to the brain,” said Mauricio Concha, MD, medical director of the Acute Stroke Program at Sarasota Memorial. “The catheter technology gives us a vital tool to aid brain healing and enhance patients’ recovery.”

Induced hypothermia has been used to treat cardiac bypass patients, but only recently has the therapy been employed for cardiac arrest.

Here’s how the cooling catheter technology works:

First, a temperature probe catheter is inserted into the bladder of the patient to monitor body temperature. The catheter is connected via a thin cable to the Alsius CoolGard 3000® temperature control system. Next, a heat exchange catheter, a long, thin, soft tube with three balloons, is inserted through a vein at the top of the leg and guided over a wire to its resting place below the heart. Cooling saline runs from the CoolGard 3000 system through tubing into the catheter, down through the balloons. The fluid is then re-circulated back to the system in a closed-loop. Blood is cooled as it passes by the balloons. No fluid is infused into the patient, nor is blood circulated outside of the body. In addition to allowing staff to cool the body more precisely than previous methods, reducing the brain's need for oxygen, the catheter also gives better control over the warming process, permitting physicians to bring patients’ temperatures back up a fraction of a degree at a time.

“The intravascular cooling catheter has been an effective means of inducing hypothermia in patients resuscitated after cardiac arrest, and is an example of the kind of state-of-the-art technology that has made Sarasota Memorial a nationally ranked provider of top-quality care,” said Kenneth Hurwitz, MD, medical director of Critical Care Services at Sarasota Memorial.

Previously, staff would have used chilled blankets and ice packs, a cumbersome, less exact method to lower body temperature.

The catheter technology was purchased with a generous donation from Louis and Gloria Flanzer.