Cardiac arrests happen most often at home. Researchers knew that. What they didn’t know, until now, is this: If your home is a highrise, the higher your floor, the lower your chance of survival.
A new study published today in the Canadian Medical Association Journal examined five years of health data from the City of Toronto and Peel Regions — selected because of high population density. Specifically, researchers wanted to see what effect “vertical delay” played on life and death when someone called 911 to report a cardiac arrest. Can floor level actually determine a person’s likelihood of survival? The short, conclusive and alarming answer is yes.
Researchers examined nearly 8,000 cases of cardiac arrest between 2007 and 2012. Survival was 4.2 per cent for those living on the first or second floor. They found those who lived between the third and 15th floors had a 2.6 per cent chance of surviving to hospital discharge. Survival was “negligible” — less than one per cent — for those living on floor 16 or above. There were 30 residents in the data that went into cardiac arrest on the 25th floor or above.
“They all died,” said Dr. Laurie Morrison, a scientist at St. Michael’s Hospital and one of the study’s authors.
Researchers studied the data to see if there were any particularly “toxic neighbourhoods” where residents were more likely to die of cardiac arrest. But there were no conclusions to be drawn from geographic or socioeconomic factors.
“It doesn’t matter whether you’re poor, middle class or high class, it’s just the vertical that makes a difference,” said Morrison, who is also director of Rescu — a group that studies out-of-hospital emergency health care.
When first responders arrive at a condo or apartment building, access barriers can delay the amount of time it takes them to reach a patient. In some cases, the building is inaccessible from the outside or an elevator is unavailable. Typically, there is no defibrillation device on scene to allow a bystander to help restart the resident’s heart before emergency crews arrive.
Survival rates decrease 7 to 10 per cent with every one-minute delay to defibrillation.
“As more highrise buildings are built, in response to the demand for affordable condominium and rental properties,” the study noted, “the negative impact on community survival may increase.”
The study suggests a few interventions that may increase survival rates in highrise buildings.
Fire departments have a universal access key that gives them sole and immediate access to elevators but paramedics do not. Expanding this access to paramedics, who may be first on scene, should be an easy fix, researchers say.
“Availability of a universal key seems like a simple intervention but it has remained unaddressed for decades,” the study reported.
The study also calls on landlords, property management companies and condo boards to consider purchasing automated external defibrillators for their buildings and training staff in their use.