Washington : Scientists have stumbled on evidence that stun guns might stimulate the heart, overturning current theories that they only affect skeletal muscles.
“The frequency and the shape of the pulses generated by stun guns are designed to disable the target by overwhelming his or her control of these muscles,” state K. Nanthakumar and colleagues.
They point out that most theoretical and some experimental studies do not link cardiac stimulation with stun gun discharges, reports Sciencedaily.
But their use recently have caused several deaths, including that of Robert Dziekanski, a Montréal man and 24-year-old Chicago resident Kevin Piskura. More than 300 deaths following stun gun use have been documented, 20 of them in Canada.
These deaths are suspected of being caused by ventricular fibrillation or severely disordered heart rhythm.
Experimental studies on pigs by three independent groups found that “a stun gun discharge can stimulate the heart” depending on the location of the stun gun barbs.
One study reported that swine blood pressure was abruptly lost after discharge from a stun gun. Another study “reported the deaths of two animals caused by ventricular fibrillation immediately after the stun gun discharge”.
This suggests that sufficient current density was produced by the stun gun to stimulate the heart, which theoretically should not and could not occur.
The researchers, however, cautioned against applying data from pigs to humans, although “most of the basic mechanistic concepts in cardiac fibrillation and defibrillation are derived from animal studies, not humans”.
Nanthakumar reviewed the stun gun data on the eve of the British Columbia inquiry into Dziekanski’s death for the Canadian Medical Association Journal.