A smartphone app designed to alert nearby CPR-trained volunteers did not increase the likelihood that a person experiencing cardiac arrest received CPR or an AED before professional responders arrived, according to preliminary late-breaking science presented at the American Heart Association's Resuscitation Science Symposium 2026. The finding, from a randomized trial conducted in British Columbia and Columbus, Ohio, challenges assumptions about the added value of volunteer alerting systems in communities where bystander response is already strong.
Researchers randomly assigned cardiac arrest 911 calls to either standard EMS dispatch alone or standard dispatch plus PulsePoint Respond alerts to nearby volunteers. Among 355 people in the primary analysis, bystander CPR or AED use occurred in 69% of cases when alerts were activated and 72% with standard dispatch alone—a difference that was not statistically significant. Bystander CPR rates were 70% and 73%, respectively, and AED use was 15% and 17%. Survival to hospital discharge was about 21% in both groups. The full abstract is available via Link to abstract.
The study's implications are significant for communities considering investment in volunteer alerting technology. PulsePoint Respond connects with local 911 dispatch centers to notify nearby CPR-trained individuals when a suspected cardiac arrest occurs in public. EMS agencies pay a subscription fee, while the app is free for volunteers. The trial, however, found that in the two regions studied, bystander CPR was already common without alerts—73% in the control group—which may have left little room for the alerts to add benefit. "This unexpectedly high rate of bystander CPR may have limited the opportunity for alerted responders to provide additional benefit," said Steven Brooks, M.D., M.H.Sc., senior lead author and professor at Queen's University.
The findings apply specifically to public-location cardiac arrests with at least one app user within 400 meters. Most incidents occurred in urban areas, and median EMS arrival was about 5.6 to 5.9 minutes. In 57% of activated incidents, only one app user was nearby, and 91% had four or fewer volunteers within range. The trial does not answer whether benefits would differ for cardiac arrests in private homes, rural areas, or communities with denser volunteer networks—important questions for future research.
For policymakers and EMS agencies, the results suggest that smartphone alerting alone may not improve outcomes where bystander response is already robust, but could still hold promise in settings with lower baseline CPR rates or longer EMS response times. The American Heart Association's 2025 American Heart Association Guidelines for CPR and ECC emphasize early bystander action, and initiatives such as Join the Nation of Lifesavers by learning CPR today continue to promote training. The study was presented at the About Resuscitation Science Symposium 2026, and additional details are available in the Online Program Planner. Updated guidance from the Association is also summarized in Updated CPR guidelines tackle choking response, opioid-related emergencies and a revised Chain of Survival.
