Page 92 - 2022 Ranger Medic Handbook

CBRN – Nerve Agents
Nerve agents are considered the primary agents of threat to the US military because of their high toxicity and effective-
ness through multiple routes of entry. They are absorbed through the eyes, respiratory tract, and skin. Nerve agents are
generally referred to a group of chemicals known as organophosphates. These compounds inhibit acetylcholinesterase
(AChE) thus having acetylcholine (ACh) accumulating in the body causing multiple organ overstimulation. This produces
a cholinergic crisis from the excessive amounts of ACH: Muscarinic effects of smooth muscle contraction in airways,
SECTION 2 causing bradycardia; nicotinic effects of skeletal muscles with fasciculations seizures, fatigue, and flaccid paralysis (late
GI tract, pupils (miosis); glandular effects from eyes, nose, mouth, sweat, airways and GI tract; effect on vagus nerve
sign); preganglionic effects of tachycardia, hypertension.
LD 50 or LCT 50 : The amount of solid, liquid, or vapor sufficient to kill the average person.
Persistent, last longer than 24 hours; nonpersistent, gone in 24 hours or less

Tabun (GA), Sarin (GB), Soman (GD), G, and VX
S/Sx: Mild to moderate vapor exposure S/Sx: CNS-slowness in thinking and decision making. HEENT-miosis, blurred
or dim vision, rhinorrhea, salivation. Respiratory-SOB, chest tightness.
Large vapor exposure S/Sx: CNS-LOC, seizures, flaccid paralysis. Respiratory-apnea GI-involuntary NVD, abdominal
pain.
Liquid on skin exposure: Small-local effects such as sweating and fasciculations. Medium-systemic effects, potential
miosis. Large – CNS and respiratory effects such as respiratory failure, LOC, seizures, apnea, flaccid paralysis, miosis
MANAGEMENT: 1 × ATNAA for any patient with miosis. Mild-1 × ATNAA (self-aid) or 3 × ATNAA (buddy-aid). Moderate/
Severe-3 × ATNAA plus 1 × CANA injector even if seizure activity is not evident. Atropine 6mg IM or 8mg IV/IO should
be repeated q 3–5 mins until the drying of secretions is noted. One additional dose of 2 PAM CL should be given 1 hour
after the initial 3 doses if patient is still symptomatic.
Severe nerve agent casualties may need more than 2–3 CANA auto injectors to relieve seizure activity.
DISPOSITION: Refer to chemical casualty triage table
SPECIAL CONSIDERATIONS: Heart rate should not be a distinguishing sign due to its ability to be normal, tachycardia,
or bradycardia. Once removed from exposure vapor nerve agent effects do not worsen.
Packaging: The Antidote Treatment Nerve Agent Auto injector (ATNAA) (NSN: 6505-01-362-7427) is an auto injector
with 2mg of atropine and 600mg of 2PAM CL combined.
The Convulsant Antidote for Nerve Agents (CANA) (NSN: 6505-01-274-0951) contains 10mg of diazepam.

78 SECTION 2 PRIMARY TRAUMA PROTOCOLS