Google Pixel Watch 3 can detect loss of pulse and call 911

Google has secured FDA clearance for its first-to-market pulse detection feature intended to aid smartwatch wearers who may experience isolated medical emergencies.

Powered by an AI-based algorithm and a device "multipath heart rate sensor," the smartwatch can detect "pulselessness" caused by various medical emergencies, such as cardiac arrest, poisoning, or respiratory arrest. The watch will then automatically call and request a dispatch of emergency services. The feature was designed with input from cardiologists, global authorities on resuscitation, and Emergency Medical Service leaders, dispatchers, and paramedics, according to the company.

"When a loss of pulse event happens, it’s usually up to a bystander to give or get help," the company explains. "However, half of all loss of pulse events related to cardiac arrest, for example, are unwitnessed – leaving millions worldwide effectively no chance of receiving emergency care soon after losing their pulse."

Here's how it works: The Pixel Watch 3 harnesses integrated heart rate monitors to detect a loss of pulse, which then trigger additional sensors that search for other signs of pulse or motion. If none are detected, the watch then begins prompting the user with check-in alerts. If there is no response from the wearer, the watch will begin emanating a loud sound and display a countdown on its screen, after which it will call an emergency dispatcher through the LTE-enabled smartwatch or connected smartphone.

Google makes it clear in the fine print, however, that the feature is not intended for those with preexisting heart conditions or who require cardiac monitoring.

The Loss of Pulse Detector feature was first announced in August, available to select market across U.K, France, Austria, Denmark, Ireland, the Netherlands, Norway, Sweden and Switzerland. Since then, the feature has expanded to 14 countries. It will finally roll out to U.S.-based Pixel Watch 3 owners in March.