All commercial aircraft should be equipped with automated external defibrillators (AEDs) and have flight crew members who know how to use them to treat sudden cardiac arrest, according to a review of current aviation safety standards.

Researchers found that in-flight cardiac arrest (IFCA) is rare, accounting for less than 1% of all in-flight medical emergencies. But when it does occur, it is highly fatal, accounting for most in-flight casualties.

Prompt recognition, cardiopulmonary resuscitation (CPR), and the use of an AED were all strongly associated with improved patient outcomes.

“To help patient survival in the skies, airlines should consider adopting universal and standardized AED access, in-flight specific CPR training, and clearer legal mandates and protections,” the authors wrote.

The findings were published on December 3 in the Canadian Journal of Cardiology.

AEDs Improve Survival

The aim of the review was to explore the complexities of sudden cardiac arrest on commercial flights, including the incidence and risk for IFCA, the effectiveness of AEDs, the type and effectiveness of airline CPR training, and the legal aspects of providing emergency care.

“I was on a flight, working on a paper on the sudden cardiac death of a 12-year-old boy, when it occurred to me to ask the flight attendant if there was an AED on board,” study author Mario Bassi, MD, a resident in the Department of Anesthesiology and Pain Medicine at the University of Ottawa in Ottawa, told Medscape News Canada.

“She said I was the first person to ever ask her that. It was an Air Canada flight, and yes, they did have one, but that got me thinking about what must be done to improve survival in these events,” Bassi said.

The review found that AEDs were very effective at treating and improving patient survival from IFCA and could significantly boost survival rates.

IFCA accounted for 0.3% of in-flight medical emergencies but was responsible for 86% of in-flight deaths.

Risk factors for IFCA included age, male sex, duration of flight, and past cardiac history.

The proportion of patients with IFCA who survived their in-flight event to hospital admission without an AED being used was 6%, whereas 21%-70% of patients for whom an AED was used survived to hospital admission.

Good Samaritan laws have been enacted to protect healthcare professionals from a lawsuit if they are acting in good faith and without criminal intent. These laws have made people more willing to render assistance in medical emergencies, Bassi noted.

“In Canada, unless there is gross negligence or foul play suspected, you are officially immune from a lawsuit for liability if something goes wrong. The biggest factor for survival from cardiac arrest is the time to CPR. If physicians and nurses feel protected, they will be more willing to take that risk and assist others,” he said.

“Improving survival rates following a flight passenger’s cardiac arrest depends on several critical considerations,” senior author Adrian Baranchuk, MD, professor of medicine at Queen’s University in Kingston, Ontario, told Medscape News Canada.

“We need to have the necessary equipment and trained individuals within the crew to deliver CPR safely and use the AED. Even if there is a medical doctor on board, he or she may never have used an AED, so we need crews to be trained to do CPR and use a defibrillator,” Baranchuk said.

“There are no universal rules that require each plane to have the necessary equipment and trained individuals within the crew to deliver CPR safely and use an AED. The big airlines have this equipment, but smaller airlines do not. We think it should be mandatory to have both on every single plane,” he said.

Doctors in the Air

A seasoned international traveler, Baranchuk says he is a magnet for in-flight medical emergencies. On one flight, a patient had a stroke 10 minutes before the plane landed. “It was the only time in my life that I landed without being seated with my seatbelt on. Instead, I was standing in front of the patient, determining whether he had his ventilation compromised. I didn’t follow the orders to be seated, but they understood,” he said.

Another time, Baranchuk was on a flight from Toronto to Buenos Aires via Santiago, Chile, when he heard the call, “Is there a doctor on board?” A man had collapsed.

On arrival in Santiago, the patient was delivered to paramedics. But the time involved in treating the patient made Baranchuk miss his connecting flight to Buenos Aires. Exhausted, he had to wait 5 hours before getting on another flight.

“They put me in first class. I close my eyes, and I hear, ‘Is there a doctor on board?’ It was a young girl who had fainted, but it was a different story, and she did very well. So it was two in a row.”

International Regulations Lacking

“There are no international regulations on carrying a medical kit, on what must be in that kit, on AEDs, or even on training the crew. That’s a major problem,” Mitchell Shulman, MDCM, emergency medicine specialist and associate professor of emergency medicine at McGill University Health Centre in Montreal, told Medscape News Canada.

“You would have thought the airline industry, of all industries, would have been the first to have rules to have these things in place. But there isn’t even a definition of emergencies,” he added.

The only country that has made it mandatory for all its airlines to carry AEDs is the US, he said.

“The US Federal Aviation Administration [FAA] has mandated all US airlines to carry AEDs on any airplane that has a payload of more than 7500 pounds, which is somewhere around 30 passengers. The FAA also mandated that the crew be required to take training in first aid, CPR, and how to use a defibrillator, which is interesting, because what physician has ever had training in doing CPR on board an airplane?” Shulman asked.

No funding for the study was reported. Bassi, Baranchuk, and Shulman reported having no relevant financial relationships.