If someone has a cardiac arrest, a drone could help before an ambulance arrives. Swedish researchers have been experimenting with drones treating an individual whose heart stops, New Scientist reported.

Out-of-hospital cardiac arrest happens to about 55 of 100,000 people in the U.S. annually, with only an 8 percent to 10 percent survival rate.

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Getting an ambulance in time could save a person’s life, but what if first responders take too long?

Researchers from the Karolinska Institute looked at an alternative: drones equipped with defibrillators that could aid a person in cardiac arrest if applied quickly. Automated external defibrillators are made to give spoken instruction so anyone can use them and are available in public spots.

Scientists tested whether drones with defibrillators can get to the scene more quickly than an ambulance. For the study, a drone was based at a fire station in Norrtälje, near Stockholm, and then was dispatched to locations within 10 kilometers where real cardiac arrest episodes had taken place in the past eight years.

The drone’s average arrival time in 18 flights to an emergency location was 5 minutes, 21 seconds, compared to real emergencies in which an ambulance took 22 minutes.

“If we can decrease the time in cardiac arrest from collapse to defibrillation by a few minutes, hundreds of lives would be saved each year,” Jacob Hollenberg told New Scientist.

The team’s study was published Tuesday in the Journal of the American Medical Association. Researchers currently are working with emergency services to dispatch the drone for real emergencies. The same team is also testing drones to search for individuals who are drowning.

“I’m convinced that the possibility of using drones in medical emergencies is enormous,” he said.

Drones Saving Humans

Drone use for those in cardiac arrest isn’t the only way the technology can help humans. A DJI report released in March said drones saved the lives of at least 38 people between March 2016 and February 2017. Overall, 59 lives have been saved by drones. Of those lives, 20 were saved by civilians helping a rescue team, DJI reported.

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A trained rescue team of five takes about two hours to find their target in a one-kilometer area while a drone can cover that location and identify the subject within 20 minutes, another DJI study found. That’s almost six times faster than a group working on foot.

Meanwhile, Verizon announced in April it tested a large drone that could provide service during an emergency using a “flying cell site.” The company had previously listed ways it plans to use drone technology.

“UAV technology will be a critical tool for emergency response in the future,” Verizon said in January. “Drones are already being used to look for lost hikers, for example, but someday soon, they could do much more than just provide data.”