According to the Heart and Stroke Foundation, if delivered in the first few minutes, defibrillation and CPR can double the survival rate of cardiac arrest, but with each passing minute, the probability of survival decreases seven to 10 percentage points.

Transport Canada currently lists defibrillators as an optional, but not required, piece of emergency equipment for Canadian airlines, according to the organization's emergency equipment regulations on its website. 

If airlines do provide additional medical equipment, like a defibrillator, the airline is required to train staff on how to operate the devices, a representative of Transport Canada told CBC in an email.

Planes are required to carry a list of emergency equipment including first aid kits, fire extinguishers, portable oxygen and flashlights.

In the United States, the Federal Aviation Administration (FAA) has required all airlines based in that country to stock defibrillators on all airplanes since 2004.

Source: CBC News