Science 20 - Looking at data from 8,216 adults who suffered an out-of-hospital cardiac arrest treated by 911-initiated first responders in the City of Toronto and nearby Peel Region from January 2007 to December 2012, the authors found 3.8 per cent survived until they could be discharged from a hospital. Survival was 4.2 per cent for people living below the third floor and 2.6 per cent for people living on or above the third floor.
"Cardiac arrests that occur in high-rise buildings pose unique barriers for 911-initiated first responders," said Ian Drennan, lead author of the study..."Building access issues, elevator delays and extended distance from the emergency vehicle to the patient can all contribute to longer times for 911-initiated first responders to reach the patient and start time-sensitive, potentially life-saving resuscitation."
He says when they went back and looked at the exact floor the patients lived on, they found decreased survival rates as the floors got higher. Survival above the 16th floor was 0.9 per cent (of 216 cases, only two survived). There were no survivors to hospital discharge of the 30 cardiac arrests above the 25th floor.
"Patients who survived tended to be younger, their cardiac arrest was more often witnessed by bystanders, and bystanders were more likely to perform CPR," Drennan said, noting the rate of bystander AED use was very low in this study. "They also had shorter times for 911-initiated first responders to get to the scene and to the patient."
"After collapse from sudden cardiac arrest, early bystander CPR and a shock from a publicly accessible automated external defibrillator can make the difference between life and death," Drennan said. "Effective CPR performed by a bystander immediately after cardiac arrest can more than double a person's chance of survival, but only 30 per cent of cardiac arrest victims get CPR from a bystander. With a rapidly deteriorating heart rhythm, in the absence of bystander CPR and defibrillation, cardiac arrests that occurred on higher floors may have a lower probability of survival due to the delay to patient contact by 911-initiated first responders. This early period is essential for bystander interventions by a family member, friend, or other willing person to improve survival."