Cooling a patient’s body temperature after cardiac arrest has been shown to reduce the likelihood of severe brain damage and death, but the treatment is usually only provided in hospitals.
Physicians at Sunnybrook Health Sciences Centre, however, have launched a new trial to examine whether making the cooling treatment available in ambulances, and having it administered by paramedics, can improve patient outcomes.
“We know that we can prevent brain damage, and save more lives, by cooling a patient. However, it is often not administered quickly enough, and not all patients receive it,” says Dr. Damon Scales, the trial’s principal investigator and staff physician, Department of Critical Care Medicine at Sunnybrook.
The trial, which is being conducted in partnership with St. Michael’s Hospital, launched in early July. Paramedics have since treated a patient in the field using cooling, a first in Ontario.
Cooling, which is also known as therapeutic hypothermia, involves administering a chilled saline solution intravenously to the patient, along with the placement of ice packs on the neck, armpit, and groin areas. This can lower body temperature by 3 to 5 degrees Celsius. Cooling has been found to slow down the brain's need for oxygen, which can reduce the patient’s chances of severe brain damage caused by lack of blood flow during cardiac arrest.
“We believe this research will lead to changes in how cardiac arrest survivors are treated in Canada, and improve their chances of surviving without any brain damage,” says Dr. Scales.
Cardiac arrest occurs when the heart abruptly stops beating, and is a devastating event that often leads to death. In Canada, about 20,000 people annually go into cardiac arrest. Damage occurs within minutes, and many of those who survive are left comatose.
“Launching this trial has required incredible collaboration with paramedics and the Sunnybrook Centre for Prehospital Medicine, and we are very excited that we have successfully started enrolling patients in Peel Region,” says Dr. Sheldon Cheskes, Medical Director, Sunnybrook Centre for Prehospital Medicine.
The trial, which is funded by the Canadian Institutes of Health Research, is expected to last for two years and involve over 1000 patients. Sunnybrook has partnered with Emergency Medical Services (EMS) across the GTA, including Peel, Halton and Toronto. Other EMS in the region are expected to join the trial over the next few months.