Injury Due to
Electronic Control Devices
Electronic control devices, such as the cattle prod, stun gun,
and the TASER®, can lead to injuries. TASER International, Inc.
(Scottsdale, AZ) produces a series of devices that deliver high-voltage,
low-amperage electrical pulses, typically at approximately 10 per second.
The pulses are designed to induce involuntary muscle contraction,
neuromuscular incapacitation, and/or pain. The likelihood
of electrical injury is minimal.23 However, falls
or other forceful movements resulting from electric current can
lead to injury, as can use in flammable and other hazardous environments.
Some devices shoot wires with fishhook-like barbs on the ends that
penetrate and hook into the skin.
Most electronic control device injuries are limited to superficial
punctures, and minor lacerations and cutaneous burns. Reported significant
injuries have included eye perforation, testicular torsion, and
pneumothorax, as well as blunt trauma from falls and burns. Burns
may occur when electronic control devices are used in flammable environments
or when used to incapacitate someone on a hot surface. The majority
of deaths that have followed the use of electronic control devices
have occurred in persons who were extremely ill and agitated due to
psychosis, stimulant drugs, or other conditions. Many of these patients
have the excited delirium syndrome. Unanticipated deaths occur in
persons showing initial agitation who calm down, become quiet for
a number of minutes and then develop respiratory arrest followed
by cardiac arrest. This series of events has been noted for >100
years in psychotic patients, but is now most common in association
with stimulant drug abuse. Death can also result from amphetamine-related
vasospasm that can produce myocardial or cerebral infarction. The
clinical conditions to be sought on examination and testing of patients
who have been extremely agitated or who appear ill include
those conditions that are caused by severe agitation and stimulant
drug effects. These conditions include life-threatening:
- Metabolic acidosis
- Respiratory acidosis (sudden onset when exhaustion occurs)
- Rhabdomyolysis (creatine phosphokinase more than five times
the upper limit of normal).
Cardiac monitoring and other testing is not needed just
because a TASER® has been used. The physician should try
to find out why the TASER® was used and obtain a history
of the patient’s behavior. Careful evaluation and monitoring
is needed in the ill-appearing patient. Patients who do not appear
to be normal should be evaluated, keeping in mind the list of conditions
above. Ill-appearing patients should be evaluated and treated in
the same way as all patients who may have sustained blunt trauma,
or who have ingested unknown substances. If sedation is needed,
benzodiazepines, ketamine, or other medications can be used. Hypertension
may resolve with sedation. Hypotension can occur due to illicit
drug effects and dehydration due to hyperthermia, excess physical
activity, and decreased food and fluid intake.
Cardiac and respiratory monitoring are indicated until the patient’s
condition appears to be stable. At present, no data exist to indicate
the observation time needed after agitation has resolved. Patients
who do not appear to be well should be examined for the problems
described above. An accurate temperature and arterial blood gases
are especially important. A 12-lead ECG is indicated not for electronic
control device effects, but rather to quickly take note of and treat
hyperkalemia and other metabolic and drug effects.
A series of human studies have found that the TASER® does
not cause or worsen hyperthermia, hyperkalemia, hypoxia, acidosis,
and a variety of other problems often seen with in-custody deaths.24–27 There
are small increases in serum lactate with TASER® use, but
serum pH does not decrease because of an increase in minute volume
(hyperventilation) that is associated with TASER® use.
In contrast, animal studies are done under the constraint that the
animals feel no pain. This requires anesthesia that produces significant
respiratory depression. Therefore, the animals do not breathe enough
to maintain oxygenation and a normal acid-base balance. Animals
become acidotic and sometimes die during experiments for undetermined
reasons. This has not been observed in any of the human studies.
Therefore, the results of human trials are relevant to one’s
understanding of clinical cases, and animal studies are not relevant.
for Patients Who Have Not Been Severely Agitated
Patients who have calmed down, have no history of loss
of consciousness or significant cardiac disease, and appear well
can usually be discharged with no ECG or other testing beyond vital
signs and a physical examination.
for Patients Who Have Been Severely Agitated
Patients can be discharged if:
- There are no abnormalities requiring treatment related
to evaluation of vital signs including temperature, 12-lead ECG,
electrolytes, arterial blood gases, and creatine phosphokinase.
- The patient has calmed down, has no history of loss of consciousness, and
no history of significant cardiac disease.
- The patient appears well on physical examination.
- After calming down, the patient has undergone
2 hours of cardiac monitoring along with pulse oximetry (or electronic