Page 98 - Journal of Special Operations Medicine - Winter 2015

In rare instances, fatal arrhythmias have been reported Taser International lowered its targeting guideline in
after exposure to an electrical weapon. 14,15 This is same September 2009, suggesting to officers that if they were
claim made by ACLU and Amnesty International. The confronting subjects face to face, they should attempt
lingering concern is whether electrical weapons can to straddle the beltline with their probe placement.
cause cardiac arrhythmias in subjects in the setting of Investigations continued, attempting to establish safe
mental disease, intoxicants, hyperadrenergic states, car- “heart-to-dart” distances and VF thresholds. 24,25 They
diac or pulmonary comorbidities, metabolic abnormali- concluded that none of these cases, transcardiac or oth-
ties, and thermoregulatory dysfunction. Suspects in a erwise, produced immediately fatal dysrhythmias and
state of agitation caused by intoxication from cocaine, that these data support the overall safety of CEWs. Con-
amphetamines, or phencyclidine often cause themselves cern was raised that multiple 5-second applications
26
to come into contact with police and are exposed to a might be creating systemic acidotic changes, either respi-
CEW to facilitate apprehension. ratory (from altered intercostal and diaphragm move-
ment) or metabolic (from lactic acid associated with
A detailed systematic review of CEWs found no evi- extended contraction of large-muscle groups). An expert
dence they cause “dangerous laboratory abnormalities, panel of medical and law enforcement experts, commis-
physiologic changes or immediate or delayed cardiac sioned by the US National Institute of Justice, published
ischemia or arrhythmias” when exposure lasts 15 sec- a guideline stating that “because the physiologic effects
12
onds or less. Further studies and reviews reached the of prolonged or repeated CEW exposure are not fully
same conclusion. 13–16 Further anecdotal evidence against understood, law enforcement officers should refrain,
harm is in the hundreds of thousands of training expo- when possible, from continuous activations of greater
sures received by police officers over the years. There than 15 seconds, as few studies have reported on longer
is no reported injury or death associated in this setting. time frames.” Considerable controversy was raised in
27
A study reviewing the use of electrical weapons against 2012 when a case series of eight deaths was reviewed in
minors with a sample size of 100 showed no significant the Journal of the American Heart Association and it
injuries or death. 17 was asserted that “ECD stimulation can cause cardiac
electrical capture and provoke cardiac arrest due to ven-
Early animal studies, such as that of McDaniel et al, tricular tachycardia/ventricular fibrillation.” Multiple
28
18
found that the safety index for an NMI discharge was responses 29–31 to that study were received, refuting inter-
significantly and positively associated with weight, but pretation of these data and calling for further research.
that discharge levels have an extremely low probability
of inducing ventricular fibrillation (VF). Attempting to In 2013, a summary document titled “The Health Ef-
account for the subject bias between “normal” volun- fects of Conducted Energy Weapons” was published.
32
teers and the drugged or psychotic individuals common It is an extensive, well-written and -researched docu-
in field applications, researchers tried to document car- ment. In it, the expert panel summarizes the issue of in-
diologic and other physiologic changes in resting and custody deaths quite succinctly:
19
exhausted 20,21 volunteers. Study of methamphetamine-
intoxicated animals was also undertaken. In all these Sudden in-custody death resulting from a use-
22
studies, CEW use was found to be reasonably safe. of-force event typically involves a complicated
scenario that includes [agitation, physical or
As the field use of CEWs continued to grow, the prac- chemical restraint, disorientation, stress or exer-
ticality of examining actual deployment outcomes tion, preexisting health conditions, and the use
became possible. A prospective, multicenter cohort of drugs and alcohol,] all of which can poten-
study in 2007 (n = 962) found that following CEW tially contribute to a sudden unexpected death.
23
use, 99.7% of subjects had no injuries or had minor This makes it difficult to isolate the contribution
injuries only. Direct injuries most reported were punc- of any single factor. Although the electrical char-
ture wounds (83%), contusions (10%), and lacerations acteristics of CEWs can potentially contribute
(6%). A moderate to severe injury rate was found to be to sudden in-custody death, . . . no evidence of a
0.3% and unlikely to be greater than 1%. It included clear causal relationship has been demonstrated
rhabdomyolysis (n = 1), cerebral contusion (n = 1), and by large-scale prospective studies. 32
epidural hematoma (n = 1). The first of these three cases
was judged to have an uncertain relationship to CEW The authors conclude:
application; the latter two, an indirect relationship, pre-
sumably secondary impact injuries from falling. If a causal relationship does exist, the likeli-
hood that a CEW will be the sole cause of a
In response to concern that proximity of probes to the sudden in-custody death is low. The extent to
heart and the vector of NMI current might increase risk, which the device would play a role in any death

86 Journal of Special Operations Medicine Volume 15, Edition 4/Winter 2015