NERVE AGENT EXPOSURE

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NERVE AGENT EXPOSURE
CA128
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OBJECTIVE

• Identify the specific signs and symptoms of nerve
  agent exposure

CA129
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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

Nerve synapse
CA130
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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

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
CA132
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ROUTES OF EXPOSURE

• Inhalation
• Ingestion

• Direct Contact

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INHALATION

• Nerve agents enter through respiratory system
• Rapidly and effectively enter into blood stream

Respiratory failure chief cause of death after
severe exposure
Nerve agent inhaled into respiratory system
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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

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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

• 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
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SIGNS AND SYMPTOMS OFNERVE AGENT EXPOSURE

• Miosis
• Dim or blurred vision
• Respiratory trouble
• Difficulty in breathing
• Increased oral/nasal secretions
• Localized sweating
• Nausea and vomiting

• Abdominal cramping
• Involuntary urination or bowel movements
• Heartbeat irregularities
• Generalized weakness
• Twitching or muscles spasms
• Convulsions and coma

CA138
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OTHER SIGNS AND SYMPTOMS OFNERVE AGENT EXPOSURE

• May result from early or mild exposure
• headache
• anxiety
• restlessness
• giddiness
• irritability

CA139
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FACTORS AFFECTING NERVE AGENT SIGNS AND SYMPTOMS

• Signs and symptoms may appear immediately or be
  delayed
• Reaction time depends on
• 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 persons system

CA140
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FACTORS AFFECTING NERVEAGENT 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

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INHALATION PEAK EFFECTSFROM 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
CA142
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DIRECT CONTACT PEAK EFFECTSFROM NERVE AGENT

• Absorption may continue for hours even after
  decontamination
• Effects may not occur for 1 to 18 hours
• effects usually not lethal

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OTHER POSSIBLE CAUSES

• Signs and symptoms may also be caused by
• epilepsy
• gastroenteritis
• exposure to agricultural insecticides
• emphysema
• strokes
• head trauma
• drug overdose
• heat illnesses
• allergies
• upper respiratory illnesses

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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

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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
CA146