Transcript NERVE AGENT EXPOSURE © 1999 Lockheed Martin Energy Research Corporation CA128 OBJECTIVE • Identify the specific signs and symptoms of nerve agent exposure © 1999

NERVE AGENT EXPOSURE
© 1999 Lockheed Martin Energy Research Corporation
CA128
OBJECTIVE
• Identify the specific signs and symptoms of nerve
agent exposure
© 1999 Lockheed Martin Energy Research Corporation
CA129
HOW NERVE AGENTS WORK
• Attack nervous system
– nervous system controls body functions through use of
chemicals which act as “instructions” to nerves, muscles and
glands
• Nerve agents interfere with normal chemical
instructions
© 1999 Lockheed Martin Energy Research Corporation
Nerve synapse
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NORMAL NERVOUS SYSTEM
• At nerve ending, acetylcholine is released
• Acetylcholine crosses synapse between nerve endings
– if junction with skeletal muscle, muscles cells contract
– if junction with smooth muscles, muscles move rhythmically
– if junction with gland, glandular cells secrete
• Acetylcholine is
inactivated by
acetylcholinesterase
© 1999 Lockheed Martin Energy Research Corporation
Normal activity at nerve synapse
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HOW NERVE AGENTS WORK
• Nerve agents block acetylcholinesterase so it cannot
destroy acetylcholine
– acetylcholine
accumulates and
continue to stimulate
target nerve
– muscles twitch
uncontrollably and
repetitively
– excess secretions of
glands
Nerve agent interferes with normal synapse activity
© 1999 Lockheed Martin Energy Research Corporation
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ROUTES OF EXPOSURE
• Direct
Contact
• Inhalation
• Ingestion
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INHALATION
• Nerve agents enter through
respiratory system
• Rapidly and effectively enter
into blood stream
Nerve agent inhaled into respiratory system
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Respiratory failure
chief cause of death
after severe exposure
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DIRECT CONTACT
• Skin or eyes are touched with agent vapor or liquid
• Nerve agents absorbed through skin
– VX remains on skin and absorbed more completely
– GB evaporates quickly, but still a threat
• Scrapes, cuts or other skin damage offer direct entry
points
– freshly shaven skin, sunburn, insect bites, rashes
• Eyes most sensitive organ for nerve agent vapor
effects
© 1999 Lockheed Martin Energy Research Corporation
CA135
INGESTION
• Ingestion of contaminated food
or drink, incidental hand to
mouth or eye contact, smoking
• Unlikely that agent will
contaminate food or drink
Gastrointestinal system
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SIGNS AND SYMPTOMS
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Signs are objective evidence of a medical condition
Signs are observed (runny nose, drooling)
Symptoms are subjective evidence
Symptoms are verbally communicated
(headache, eye pain)
Not all signs and symptoms may appear . . .
Dose, duration, and route of exposure
make a difference
© 1999 Lockheed Martin Energy Research Corporation
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SIGNS AND SYMPTOMS OF
NERVE AGENT EXPOSURE
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Miosis
Dim or blurred vision
Respiratory trouble
Difficulty in breathing
Increased oral/nasal
secretions
• Localized sweating
• Nausea and vomiting
© 1999 Lockheed Martin Energy Research Corporation
• Abdominal cramping
• Involuntary urination or
bowel movements
• Heartbeat irregularities
• Generalized weakness
• Twitching or muscles
spasms
• Convulsions and coma
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OTHER SIGNS AND SYMPTOMS OF
NERVE AGENT EXPOSURE
• May result from early or mild exposure:
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headache
anxiety
restlessness
giddiness
irritability
© 1999 Lockheed Martin Energy Research Corporation
CA139
FACTORS AFFECTING NERVE
AGENT SIGNS AND SYMPTOMS
• Signs and symptoms may appear immediately or be
delayed
• Reaction time depends on
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type of agent
amount of agent person has been exposed to
dose (how much a person has absorbed)
duration of exposure
route of exposure
sensitivity of person’s system
© 1999 Lockheed Martin Energy Research Corporation
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FACTORS AFFECTING NERVE
AGENT SIGNS AND SYMPTOMS
Immediate if moderate to large amounts are
inhaled
if moderate to large amounts are
spilled onto the skin
Delayed
if small amounts are involved
if agent has been absorbed through
skin in small localized area
© 1999 Lockheed Martin Energy Research Corporation
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INHALATION PEAK EFFECTS
FROM NERVE AGENT
• Effects can occur after single breath
• Immediate response within seconds
• Peak effects usually within
15 - 20 minutes
• After about 20 minutes,
effects usually maximized
and will not worsen
Respiratory system
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DIRECT CONTACT PEAK EFFECTS
FROM NERVE AGENT
• Absorption may continue for hours even after
decontamination
• Effects may not occur for 1 to 18 hours
– effects usually not lethal
© 1999 Lockheed Martin Energy Research Corporation
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OTHER POSSIBLE CAUSES
• Signs and symptoms may also be caused by
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epilepsy
gastroenteritis
exposure to agricultural insecticides
emphysema
strokes
head trauma
drug overdose
heat illnesses
allergies
upper respiratory illnesses
© 1999 Lockheed Martin Energy Research Corporation
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INITIAL FIRST AID TREATMENT
• Immediate removal from source of exposure
– severity directly proportional to absorbed dose
• Decontamination
– preferred decontamination solution is undiluted household
bleach
• Antidote administration with airway management
support as necessary
• Must be provided by properly trained and equipped
personnel
© 1999 Lockheed Martin Energy Research Corporation
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NERVE AGENT ANTIDOTE
• Atropine
– administered to block receptor sites of acetylcholine
• 2-PAM Chloride
– restores acetylcholinesterase
Two-part nerve agent antidote
© 1999 Lockheed Martin Energy Research Corporation
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