From Sunday, April 26, 2009: [LINK]
Another possible death mechanism (?)
Out of the mouths of...
...What killed Dziekanski... "This is not due to a Taser," says Deborah Mash [LINK], a neurology professor at the University of Miami who has been studying excited delirium for 20 years. "This is in the brain and they die because the mechanisms that control the heart and the lungs fail." [LINK]
Has anyone looked into the possibility that the taser shock is capable of affecting the nervous system (duh!) mechanisms such that these systems sometimes fail due to a long duration taser shock?
Perhaps, with bad luck and thus occuring in just a fraction of incidents, the central nervous system pathways that control the heart and the lungs just happen to carry enough of the randomly-placed taser current to have their stock of neurochemical transmitters depleted by long duration electric current from the taser.
In the same way that bright lights can temporarily blind you. In the same way that loud sounds can temporarily deafen you. In the same way that repeated impacts can eventually lead to numbness. In the same way that a constant smell eventually becomes imperceptible. Nervous systems eventually shut-down if they're been triggered too much.
Perhaps the taser current sometimes (randomly) rides the pathways that control the heart and lungs. Perhaps those pathways become depleted and thus incapable of functioning for a critical period.
This proposed explanation makes as much, or possibly more, sense than 'excited delirium' in many cases where the late victim obviously wasn't even as excited as the police, and certainly wasn't even the slightest bit delirious.
Something to keep in mind is that the taser is really the first device that often applies the current directly across the chest. Most of the safety standards are not written to assume that the electrician falls chest-first into box of high voltage circuitry. Those standards often assume that the current arrives on one hand, and exits down one leg. This may be an important element in solving the taser-associated death mystery.
Also, I'm very suspicious of those 'expert' calculations of smooth distributions of current through the human body (as if it made of large homogeneous chunks of material). I suspect that the current prefers to travel on small structures that are good conductors and cover larger areas (nerves?).
This post is just a suggestion for further consideration.
PS (June 2010): It's obvious to me that there are probably several different internal taser-death mechanisms. Direct cardiac impact (several variations), blood pH, depletion of neurochemical transmitters, and probably several others. Those that might be looking for just one explanation would become confused.