Heart Attack Survival Poorer in High-Rise Buildings

A new study finds that people who suffered cardiac arrest had a better chance of survival if they lived on lower floors, with survival odds decreasing as floor number increased.

Researchers at St. Michael’s Hospital (Toronto, Canada) and Sunnybrook Health Sciences Center (Toronto, Canada) conducted a retrospective observational study between January 2007 and December 2012 of 7,842 adult cases of out-of-hospital cardiac arrest, of which 5,998 (76.5%) occurred below the third floor and 1,844 (23.5%) occurred on the third floor or higher. Cardiac arrests witnessed by 911-initiated [North American emergency phone number] first responders and those with an obvious cause were excluded. The researchers then determined the effect of the floor of patient contact on cardiac arrest survival.

The results showed that survival was greater on the lower floors (4.2%) than higher ones (2.6%). On average, it took responders about six minutes from the time of the emergency services call to arrive at the building. It took them an average of three minutes between arriving at the building and first contact with the patient for those lived on the first or second floor, compared to an average of almost five minutes for those who lived on or above the third floor. The adjusted survival rate to hospital discharge was also independently associated with older age, male sex, and longer 911 response time.

In an analysis by floor, survival was a negligible 0.9% (below the 1% threshold for futility) above the 16th floor, and there were no survivors at all above the 25th floor. Among the reasons suggested was that rescuers need to go through one or more outer doors, possibly encounter an intercom system, cross a lobby, and locate the elevators before arriving at the victim’s floor. Once on the correct floor, they still have to locate the correct apartment, and then navigate their way back out of the building. The study was published on January 18, 2016, in the Canadian Medical Association Journal (CMAJ).

“Patients who survived tended to be younger, their cardiac arrest was more often witnessed by bystanders, and bystanders were more likely to perform CPR. They also had shorter times for 911-initiated first responders to get to the scene and to the patient,” said lead author paramedic Ian Drennan. “Building access issues, elevator delays, and extended distance from the emergency vehicle to the patient can all contribute to longer times for first responders to reach the patient and start time-sensitive, potentially life-saving resuscitation.”

The researchers suggested several interventions aimed at shortening response times to treatment of cardiac arrest in high-rise buildings, including improving accessibility to automated external defibrillators (AEDs) by placing them on specific floors, in building lobbies, or inside elevators; giving paramedics a universal elevator key, thus allowing them access to elevators without public interference; and alerting building security to the fact 911-initiated first responders are on the way, so they can have easy access to the building and have elevators waiting on the main floor.

Related Links:
St. Michael’s Hospital
Sunnybrook Health Sciences Center