dpt 8.1 emergency management of nerve agent casualties

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DPT 8.1

Emergency Management of Nerve Agent Casualties

DPT 8.1

Hospital Provider Management of Chemical Agent Casualties

DPT 8.1

EMS Management of Chemical Agent Casualties

DPT 8.1

Objectives

• Describe physiological actions of nerve agents

• Recognize signs and symptoms of nerve agent

exposure

• Describe emergency management of nerve

agent victims

DPT 8.1

Nerve Agents

• Tabun (GA), Sarin (GB), Soman (GD), VX

• Most toxic of the chemical agents

• Penetrate skin, eyes, lungs

• Loss of consciousness, seizures, apnea, death after large amount

• Diagnosis made clinically; confirmed in laboratory (cholinesterase)

DPT 8.1

Normal Nerve Function

AChACh

DPT 8.1

Normal Nerve Function

AChACh

DPT 8.1

Normal Nerve Function

AChACh

AChEAChE

DPT 8.1

How Nerve Agents Work

AChEAChE

AChACh GBGB

DPT 8.1

Effects of Nerve Agents

Muscarinic

– Smooth muscles

– Exocrine glands

– Cranial nerves (vagus)

Nicotinic

– Skeletal muscles

– Ganglia

Two types of cholinergic receptors:

DPT 8.1

SLUDGE-MSLUDGE-M

SSalivation

LLacrimation

UUrination

DDefecation

GGI upset – nausea/vomiting, cramps, diarrhea

EEmesis

MMuscle twitching

Signs and Symptoms of Nerve Agents Mnemonic

DPT 8.1

DUMBELSDUMBELSDDiarrhea

UUrination

MMiosis

BBradycardia, Bronchorrhea, Bronchospasm

EEmesis

LLacrimation

SSalivation, Sweating

Signs and Symptoms of Nerve Agents Newer Mnemonic

DPT 8.1

Signs and Symptoms of Nerve Agents Muscarinic Sites

• Increased secretions– Saliva

– Tears

– Runny nose

– Secretions in airways

– Secretions in gastrointestinal tract

– Sweating

DPT 8.1

Signs and Symptoms of Nerve AgentsMuscarinic Sites

• Smooth muscle contraction– Eyes: miosis

– Airways: bronchoconstriction (shortness of breath)

– Gastrointestinal: hyperactivity (nausea, vomiting, and diarrhea)

DPT 8.1

Signs and Symptoms of Nerve Agents Nicotinic Sites

• Skeletal muscles– Fasciculations

– Twitching

– Weakness

– Flaccid paralysis

• Other (ganglionic)– Tachycardia

– Hypertension GBGB

AChACh

DPT 8.1

Nerve AgentsOther Signs and Symptoms

• Cardiovascular– Tachycardia, bradycardia– Heart block, ventricular arrhythmias

• Central Nervous System– Acute

• Loss of consciousness• Seizures• Apnea

– Prolonged (4-6 weeks)• Psychological effects

DPT 8.1

Signs and Symptoms of Nerve Agents Vapor Exposure

• Mild exposure– Miosis (dim vision, eye pain), rhinorrhea, dyspnea

• Moderate exposure– Pronounced dyspnea, nausea, vomiting, diarrhea,

weakness

• Severe exposure– Immediate loss of consciousness, seizures, apnea, and

flaccid paralysis

• Vapor effects occur within seconds, peak within minutes; no late onset

DPT 8.1

Signs and Symptoms of Nerve Agents Liquid Exposure

• Mild exposure (to 18 hours)– Localized sweating– Fasciculations– No miosis

• Moderate exposure (<LD50) (to 18hours)– Gastrointestinal effects– Miosis uncommon

• Severe exposure (LD50) (<30 minutes)– Sudden loss of consciousness

– Seizures

– Apnea

– Flaccid paralysis

– Death

DPT 8.1

Diagnosis of Nerve Agent Exposure

• Symptomatic

– May be systemic or organ-specific

– Combination of symptoms is more definitive

• Situational

– Multiple casualties with similar symptoms

– Time or location factors in common

DPT 8.1

Nerve AgentsTreatment

• Removal from exposure

• Decontamination

• Airway/ventilation

– High resistance

• Antidotes

– Atropine

– 2-PAMCl

– Diazepam

DPT 8.1

Nerve Agents Treatment

• Atropine

– Antagonizes muscarinic effects

– Dries secretions; relaxes smooth muscles

– Given IV, IM, ET

• No effect on pupils

• No effect on skeletal muscles

• IV in hypoxic patient ventricular fibrillation

DPT 8.1

Nerve AgentsTreatment

• Starting dose - 2 mg

• Maximum cumulative dose - 20 mg– Total dose calculated over time; but enough must be

administered to abate severe symptoms if casualty is to survive

– Insecticide poisoning requires much more

• Side effects in normal people– Mydriasis – Blurred vision– Tachycardia– Decreased secretions and sweating

DPT 8.1

Nerve AgentsTreatment

• Atropine - How much to give?

– Until secretions are drying or dry

– Until ventilation is “easy”

• If conscious or casualty is comfortable

– Do not rely on heart rate/pupil size

DPT 8.1

Nerve AgentsTreatment

• Pralidoxime Chloride (2-PAMCl)

– Remove nerve agent from AChE in absence of aging

– 1 gram slowly (20-30 minutes) in IV infusion

• Hypertension with rapid infusion

– No effects at muscarinic sites

– Helps at nicotinic sites

AChEAChE 2-PAMCl

Nerve Nerve AgentAgent

DPT 8.1

Nerve AgentsTreatment - Autoinjectors

DPT 8.1

MARK I Injection IM vs. IV

DPT 8.1

MARK I InjectionsDispersal

DPT 8.1

Nerve AgentsTreatment

• Diazepam

– Decreases seizure activity

– Reduces seizure-induced brain injury

– Give to severely intoxicated casualties whether convulsing or not

DPT 8.1

Nerve AgentsTreatment

• No signs/symptoms

• Reassure

• Observe

– Vapor: 1 hour

– Liquid: Up to 18 hours

DPT 8.1

Nerve AgentsTreatment

• Mild vapor exposure

– Miosis, rhinorrhea - observation only

– Increasing SOB – treat

• Mild liquid exposure

– Localized fasiculations & sweating - treat

• One MARK I kit (2 mg atropine/ 600 mg 2-PAMCl)

OR

• 1 gram 2-PAMCl IV

• 2 mg atropine, IM or IV

Parenteral atropine will not

reverse miosis

Treat with:

DPT 8.1

Nerve AgentsTreatment

• Moderate vapor or

liquid exposure

– More severe

respiratory distress

– Muscular weakness

– Nausea, vomiting, and

diarrhea

– One or two MARK I kits

OR

– IV:

• 2 to 4 mg atropine

• 1gm 2-PAMCl (infusion)

Treat with:

DPT 8.1

Nerve AgentsTreatment

• Severe vapor or liquid exposure

– Unconscious

– Seizing or post-ictal

– Apneic or severe dyspnea

– Twitching or flaccid

– Effects in 2 or more body system

– 3 MARK I kits OR

– 6 mg atropine IV and

1 gram of 2-PAMCl IV

– Airway

– Ventilation/O2

– Consider diazepam 10 mg IM (2 to 5 mg IV)

– Repeat atropine every 5 to 10 minutes as needed

– Repeat 2-PAMCl in one hour

DPT 8.1

Nerve AgentsAge-Related Treatment

• Atropine

– Infant (0 to 2) 0.5 mg IM

– Child (2 to 10) 1.0 mg IM

– Adolescent (> 10) 2.0 mg IM

– Elderly 1.0 mg IM

– IV for infants and children 0.02 mg/kg

DPT 8.1

Nerve AgentsAge-Related Treatment

• 2-PAMCl

– < 20 kg 15 mg/kg IV

– > 20 kg 600-mg IM autoinjector

– Elderly 1/2 adult dose (7.5 mg/kg IV)

• 2-PAMCl-induced hypertension

– Phentolamine Adult - 5 mg IV

Child - 1 mg IV

DPT 8.1

Nerve AgentsAge-Related Treatment

•Diazepam

- Infants > 30 days old 0.2 - 0.5 mg/kg IV to 5 years q 2 to 5 min

(max 5 mg)

- Children > 5 years 1 mg IV q 2 to 5 min

(max 10 mg)

DPT 8.1

Nerve AgentsSummary

• Vapor exposure

– Symptoms develop suddenly

– Most ambulatory victims require minimal intervention

– Risk of secondary contamination, which is minimized by removing the victim’s clothing

– Requires immediate access to antidotes

• Liquid exposure

– Symptoms delayed minutes to hours

– Greater need for decontamination

– High risk of secondary contamination; victims require decontamination (clothing removal & washdown)

– Requires immediate access to antidotes

DPT 8.1

DOMESTICDOMESTICPREPAREDNESSPREPAREDNESSTRAINING TEAMTRAINING TEAM

HELPLINE: (800) 368-6498HELPLINE: (800) 368-6498FAX: (410) 612-0715FAX: (410) 612-0715

E-MAIL: cbhelp@apgea.army.milE-MAIL: cbhelp@apgea.army.mil

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