Although they're generally a lot safer than guns, conducted electrical weapons (CEWs) such as the Taser still have been implicated in deaths by cardiac arrest. In an effort to lower the chances of that happening, researchers at North Carolina's Wake Forest Baptist Medical Center recently altered a CEW so that it could both deliver an incapacitating electrical charge, and monitor the victim's heart rate while doing so.

"The basic components of a CEW – probes that penetrate the skin while attached to insulated wires connected to an electronic device – are functionally similar to what is used to obtain an electrocardiogram," says Dr. Jason P. Stopyra, who led the study. "We set out to see if we could combine a heart monitoring device with an existing CEW to detect and store cardiac rhythms without impeding the function of the weapon, and we succeeded."

The researchers started with regular law enforcement CEW cartridges, then modified them to transmit electrocardiogram (EKG) signals. A miniaturized EKG recorder on a standard-issue CEW received those signals from the cartridges, once they struck human test subjects. The cartridges still also delivered an incapacitating electrical current.

"This serves as proof-of-concept that safety measures such as cardiac biomonitoring can be incorporated into CEWs and possibly other law enforcement devices," says Dr. William B. Bozeman, senior author of the study. "Such devices, when fully developed, could alert law enforcement personnel to potential medical issues in real time and promote the rapid treatment of individuals who may suffer a medical crisis while in custody."