# Presentation: 094231

## NERVE AGENT EXPOSURE

**NERVE AGENT EXPOSURE**

## OBJECTIVE

- Identify the specific signs and symptoms of nerve agent exposure

- CA129

## HOW NERVE AGENTS WORK

**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

## NORMAL NERVOUS SYSTEM

**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

## 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

- CA132

- Nerve agent interferes with normal synapse activity

## ROUTES OF EXPOSURE

- CA133

**ROUTES OF EXPOSURE**

- Inhalation
- Ingestion

- Direct Contact

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

- Rapidly and effectively enter into blood stream

**Respiratory failure**
**chief cause of death**
**after severe exposure**

- CA134

**INHALATION**

- Nerve agent inhaled into respiratory system

## DIRECT CONTACT

**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

## INGESTION

**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

## 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)

- CA137

- Not all signs and symptoms may appear . . .
- Dose, duration, and route of exposure make a difference

## SIGNS AND SYMPTOMS OFNERVE AGENT EXPOSURE

**SIGNS AND SYMPTOMS OF****NERVE 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

##  OTHER SIGNS AND SYMPTOMS OFNERVE AGENT EXPOSURE

** ****OTHER SIGNS AND SYMPTOMS OF****NERVE AGENT EXPOSURE**

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

## FACTORS AFFECTING NERVE  AGENT SIGNS AND SYMPTOMS

**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 person’s system

## 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

**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**

- CA141

**FACTORS AFFECTING NERVE****AGENT SIGNS AND SYMPTOMS**

## INHALATION PEAK EFFECTSFROM NERVE AGENT

**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

## DIRECT CONTACT PEAK EFFECTSFROM NERVE AGENT

**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

## OTHER POSSIBLE CAUSES

**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

## INITIAL FIRST AID TREATMENT

**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

## NERVE AGENT ANTIDOTE

**NERVE AGENT ANTIDOTE**

- Atropine
- administered to block receptor sites of acetylcholine
- 2-PAM Chloride
- restores acetylcholinesterase

- Two-part nerve agent antidote