The patient was trapped in an enclosed space with toxic gases or fumes (e.g., produced by a fire, a leak, evaporation of a solvent, a chemical reaction, or fermentation of silage) and comes to the emergency department or acute care center complaining of coughing, wheezing, shortness of breath, irritated or runny eyes or nose, or skin irritation. More severe symptoms include confusion and narcosis, dizziness, headache, chest pain, nausea, vomiting, and rapidly evolving upper airway obstruction.

 

Symptoms may develop immediately or after a lag of as much as 1 day. On physical examination, the victim may smell of the agent or be covered with soot or burns. Inflammation of the eyes, nose, mouth, or upper airway may be visible, and pulmonary irritation may be evident in the form of coughing, rhonchi, rales, or wheezing, although these signs may also take up to 1 day to develop.