Rhinorrhea nerve agent exposure

Symptoms Nerve agents exposures results in rhinorrhea, chest tightness, pinpoint pupils, shortness of breath, excessive salivation and sweating, nausea, vomiting, abdominal cramps, involuntary defecation and urination, muscle twitching, confusion, seizures, flaccid paralysis, coma, respiratory failure, and death. 

Rhinorrhea is common after both local and systemic nerve agent exposure. It may occur soon after exposure to a small amount of vapor and sometimes precedes miosis and dim vision, or it may occur in the absence of miosis. Even a relatively small exposure to vapor may cause severe rhinorrhea. One exposed worker compared the nasal secretions to the flow from a leaking faucet, and another said that they were much worse than those produced by a cold or hay fever (personal observation). 

Rhinorrhea may precede miosis as the first indication of exposure to even small amounts of nerve agent vapor. After exposure to high concentrations/ doses by any route, rhinorrhea occurs as part of the generalized increase in secretions. Direct ocular contact to nerve agents may cause miosis, conjunctival injection, pain in or around the eyes, and dim or blurred vision. 

Although miosis is a characteristic sign of exposure to the nerve agent, rhinorrhea may be the first indication. It severity is dose dependent. 

The initial effects of nerve agents depend on the dose and route of exposure. A small inhalation exposure from nerve agent vapor causes a response in the eyes, nose and airway, such as miosis, conjunctival injection, eye pain, rhinorrhea, bron-choconstriction, excessive bronchial secretions, and mild to moderate dyspnea (9,13,18). Larger exposures cause central nervous system effects within seconds to minutes, including loss of consciousness, seizures, and central apnea. Death can occur within 5-lOmin of a lethal dose, usually due to respiratory failure from the combined effects of respiratory muscle paralysis, loss of airway control and profuse bronchorrhea (13,14). 

Miosis (pinpointing of pupils) and rhinorrhea (runny nose) may be the first indications of exposure to nerve agent vapor. Miosis is indicative of vapor exposure unless liquid has been in contact with the eyes. Difficulty breathing (shortness of breath or tightness of the chest) may also be present. Lethal amounts of vapor cause loss of consciousness and convulsions within 30 seconds to 2 minutes of exposure, followed by cessation of breathing and flaccid paralysis after several more minutes. 

An individual with mild or moderate dyspnea and possibly with miosis, rhinorrhea, or both can be classified as having a mild exposure to nerve agent. The symptoms indicate that the casualty has been exposed to a nerve agent vapor and may or may not have been contaminated by a liquid agent. 

A casualty who has had moderate exposure to either a nerve agent vapor alone or to vapor and liquid will have severe dyspnea, with accompanying physical signs, and probably also miosis and rhinorrhea. The casualty should be thoroughly decontaminated (Remember exposure to vapor alone does not require decontamination) and blood should be drawn for assay of RBC-ChE activity if assay facilities are available. The contents of three MARK I kits and diazepam should be given if the casualty is seen within minutes of exposure. If seen later than 10 minutes after exposure, the casualty should receive the contents of two kits. Additional atropine should be given at 5- to 10-minute intervals until the dyspnea subsides. No more than three MARK I kits should be used however, additional atropine alone should be administered if the contents of three kits do not relieve the dyspnea after 10 to 15 minutes. If there is reason to suspect liquid contamination, the patient should be kept under observation for 18 hours. 

Several milligrams of VX, the least volatile nerve agent, absorbed through the skin will cause clinical signs and symptoms.1112 A Ct (the concentration [C] of agent vapor or aerosol in air, as mg/m3, multiplied by the time [t] of exposure, in minutes) of 2 to 3 mg min/m3 of sarin will produce miosis and rhinorrhea in man.13 This Ct can be attained with exposure to a concentration of 2 mg/m3 for 1 minute or a concentration of 0.05 mg/m3 for 40 minutes. 

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