The TASER® Device:
Human Research Update
Jeffrey D. Ho, MD, FACEP
Dept. of Emergency Medicine
Hennepin County Medical Center/University of MN Medical School
May 16, 2008

Professional Qualifications
y Emergency Medicine Physician
y Minnesota Peace Officer
y Academic Medical Researcher

Disclosure
y Consultant to TASER International (Non-Employee)
y Personal Shareholder (No Options)
y Partial Funding of some research projects from TASER
International
y Conflict Management Plan through the Minneapolis
Medical Research Foundation
y Conflict Management by Scientific Peer Review

Objectives

Why do people die after arrest?

Misunderstanding Electricity
y Electricity = Danger
y Wall Sockets
y Overhead Power Lines
y Electricity as a form of Capital Punishment

Misunderstanding Electricity
y If Electricity causes a cardiac arrest, it does so in a very
predictable fashion. Ventricular Tachycardia (VT),
Ventricular Fibrillation (VF) result.
y Why then, are the cases of sudden custodial death
documented as rhythms other than VF or VT upon
paramedic arrival? (They are typically Pulseless
Electrical Activity or Asystole)
y Why then, does history have documentation of sudden
custodial death cases before the invention of the TASER
in rhythms other than VF or VT?

Misapplication of Logic
y The “Post Hoc Fallacy”
y “After this, therefore because of this.”
y Assumes events close in time have a cause/effect relationship
y Scientific process is needed to either validate or refute
y Example: Rooster crowing associated with the sun rising

TASER Research
y TASER devices are not toys
y They are not therapeutic medical devices
y They should be evaluated in the context of their use
y Start with the question of “What happens if. . .?”
y Not with the question of “Can I cause this. . .?”

Animal Research
y Animal models can point towards certain directions but
interpret the results with caution
y Animal models are not great human substitutes.
y Animals are anatomically different
y Most are smaller in mass than a human
y Some animal research has had concerning conclusions
y These conclusions are reached in artificial environments
y Human study in these areas have shown opposite conclusions

Existing Human Evidence
y TASER International has estimated over 675,000
voluntary training exposures with no deaths
y What similarities exist in my studies?
y Health/Age/Gender
y Stature
y Probe Position

Human Research
y Ho J, et al: Cardiovascular and physiologic effects of
conducted electrical weapon discharge in resting adults.
AcadEmerg Med, 2006.
y No significant findings

y Ho J, et al: Respiratory effect of prolonged electrical
weapon application on human volunteers. AcadEmerg
Med, 2007.
y 15 second exposure
y People breathe faster during exposure

Minute ventilation Before = 13.2, pH Before = 7.4
Minute ventilation During = 18.7
pH After = 7.4

Human Research
y Ho J, et al: Prolonged TASER use on exhausted humans
does not worsen markers of acidosis. Am J Emerg Med,
2007-2008 In Press.
y 15 seconds on acidotic, exhausted adults
y No worsening of acidosis that is already present

y Ho J, et al: Impact of conducted electrical weapons in a
mentally ill population. Am J Emerg Med, 2007.
y Review of TASER use during mental illness encounters.
y TASER use 45% of time instead of justifiable deadly force

Human Research
y Ho J, et al: Absence of electrocardiographic change
following prolonged application of a conducted
electrical weapon in physically exhausted adults.
AcadEmerg Med, 2007 supplement.
y No EKG changes found after exposure

y Moscati R, Ho J, et al: Physiologic effects of prolonged
conducted electrical weapon discharge in ethanol
intoxicated adults. AcadEmerg Med, 2007 supplement.
y Alcohol consumption causes respiratory slowing
y No changes when TASER is used on intoxicated humans

Human Research
y Dawes D, Ho J, et al: Effect of prolonged discharge from
a conducted electrical weapon on human core
temperature. J Forensic Sci, 2008 In Press.
y No elevation in core temperature found

Human Research (Drive Stun)
y Ho J, et al: Prolonged TASER drive stun exposure in
humans does not cause worrisome biomarker changes.
PrehospEmerg Care, 2008 Supplement.
y Drive stuns do not markedly change physiology

y Ho J, et al: Confirmation of respiration during trapezial
conducted electrical weapon application. AcadEmerg
Med, 2008.
y Dynamic demonstration that breathing occurs

Human Research
y Ho J, et al: Echocardiographic evaluation of a TASER
X26 application in the ideal human cardiac axis.
AcadEmerg Med, 2008 In Press.
y Replicates 3 concerning swine studies
y No evidence of cardiac rhythm problem in humans

Human Research
y Current Work:
y XREP work on humans
y C2 work on humans
y X26 methamphetamine study
y X26 human studies examining various physiology
parameters under various stress factors

Future Research Example

VS.

VS.

Grappling and Pepper Spray exposure appear to be more stressful than TASER

Validation Studies
„ Chan et al. Respiratory and Ventilatory Effects of the TASER on Human
Subjects. AcadEmerg Med , 2007;14 (Suppl 1):191-192.
„ Sloane et al. Serum Troponin I Measurement of Subjects Exposed to the
TASER X-26. AcadEmerg Med, 2007:14 (Suppl1):103-104.
„ Vilke et al. Cardiovascular and Metabolic Effects of the TASER on Human
Subjects. AcadEmerg Med, 2007:14 (Suppl1):104-105
„ Vilke et al. Does the TASER Cause Electrical Changes in Twelve Lead ECG
Monitoring of Human Subjects. AcadEmerg Med, 2007:14 (Suppl1):104.
„ Sloane et al. Cardiac Monitoring of Human Subjects Exposed to the
TASER. J Emerg Med, 2007;33:113-117.
„ Barnes Jr DG, et al. Cardiac effects of the TASER conducted energy
weapon. Ann Emerg Med, 2007;48 (supplement):S102.
„ Bozeman WP, et al. Injury profile of electrical conducted energy
weapons. Ann Emerg Med, 2007;50 (supplement):S565.

Conclusions
y Beware of faulty logic
y The current body of human research does not support a
connection between the TASER device and sudden death
through any mechanism that is known to modern
medicine

Questions?