Acute inhalation injury.

Toxic inhalants cause injury through a variety of different mechanisms, including direct irritation of the respiratory tract mucosa, asphyxiation, and systemic absorption of the toxin. The nature and extent of the acute injury depends on the inhalant's water solubility, aerodynamic features, pH, and concentration. In addition, a patient's underlying respiratory function may affect the clinical response. Smoke inhalation is a particularly challenging clinical problem because patients often are exposed to a large number of inhaled toxins and may suffer thermal injury to the respiratory tract as well. Several chronic respiratory problems have been identified following acute inhalation injuries. Chronic airflow obstruction has been reported in patients exposed to ammonia, chlorine, nitrogen dioxide, and sulfur dioxide; bronchiolitis obliterans may follow exposure to nitrogen dioxide and sulfur dioxide. Inhalation injuries can be difficult to manage because exposures occur infrequently, and the exact toxic agents involved often are not known immediately. Prevention of occupational exposures remains a cornerstone in the overall management of inhalation injuries.