Biomedical Engineering Reference
In-Depth Information
tion and the loss of substantial quantities of fluids
and electrolytes from exocrine gland secretions,
vomitus, and diarrhea. IV fluids readily restore
circulating volume and atropine promptly reverses
the muscarinic crisis. Thus circulatory collapse is
of less concern in managing nerve agent casualties
than respiratory impairment.
6.2.5.3 Diazepam
Diazepam is a benzodiazepine used to decrease
convulsive activity and reduce the brain damage
caused by prolonged seizure activity. The adult and
adolescent dose is 10mg and the dose for children
is 0.05-0.3mg/kg with a maximum single dose
of 5mg. Diazepam may be repeated every 15-30
minutes to control the seizure activity. After the
onset of paralysis electrical seizure bursts continue
even though the skeletal muscle activity is not
apparent.
6.3 Cyanide
6.3.1 History
Cyanide is ubiquitous in nature and nearly all
living organisms have enzymes to detoxify it.
The fruits and seeds, especially pits, of many
plants, such as cherries, peaches, almonds, and
lima beans contain cyanogens capable of releasing
free cyanide following enzymatic degradation [11].
The edible portion (the roots) of the cassava plant
(widely used as a food staple in many parts of
the world) is also cyanogenic [12]. Still cyanide
has been used through out history as a poison.
Nero of Rome used cherry laurel water to poison
members of his family and others who displeased
him. Napoleon III proposed the use of cyanide
on soldier's bayonets to enhance effectiveness.
Cyanides are also called “blood agents,” an anti-
quated term of military classification from World
War I. At the time of the introduction of cyanide
in World War I, the other chemical agents in use
caused mainly local effects. In contrast, inhaled
cyanide produces systemic effects and was thought
to be carried in the blood; hence the term “blood
agent.” The French used about 4000 tons of
cyanide in World War I without notable military
success because the small one- to two-pound muni-
tions used could not deliver the large amounts
needed to cause biological effects. During World
War II the Nazi's used Zyklon B, a cyanide based
rodentcide, to kill millions of prisoners of war and
Jews. In the late 1980s cyanide-like agents may
have been used against the inhabitants of the Syrian
city of Hama and the Kurdish city of Halabja,
Iraq, and Shahabad, Iran during the Iran-Iraq War.
In 1978 the followers of the reverend Jim Jones
committed mass suicide by drinking cyanide laced
Kool-Aid, and cyanide laced Tylenol was respon-
sible for multiple deaths in Washington State in
6.2.5.4 Supportive care
Severely exposed patients may require up to
several days of assisted or controlled ventilation
in addition to treatment for residual muscarinism
(sweating, wheezing, or salivation) and neuro-
muscular dysfunction. The experience in Japan
shows that partial acetylchoinestrase regenera-
tion sufficed to restore neuromuscular transmis-
sion within days. Nerve agents can also affect
the circulation adversely through vagal stimula-
Table 6.6
Pralidoxime chloride dosing
Patient
Dosing Recommendation
Adults
1-2 g intravenously (severe
exposure) or intramuscular
(mild to moderate exposure)
repeated hourly for two or
three additional doses
Adolescent
1-2 g intravenously (severe
exposure) or intramuscular
(mild to moderate exposure)
repeated hourly for two or
three additional doses
Child (2-10 yrs old)
25-50mg/kg intravenously
(severe exposure) or
intramuscular (mild to
moderate exposure) repeated
hourly for two or three
additional doses
Infant (<2 yrs old)
25-50mg/kg intravenously
(severe exposure) or
intramuscular (mild to
moderate exposure) repeated
hourly for two or three
additional doses
