Unilateral absence of ventilation and perfusion associated with a bronchial mucous plug.

We have described a patient in whom loss of ventilation and perfusion of an entire lung resulted from mucous impaction of a major bronchus. Mucous plugging was associated with the combination of asthma and decreased cough effectiveness due to paraplegia. Removal of the obstruction by bronchial aspiration followed by vigorous pulmonary physical therapy resulted in return of both ventilation and perfusion to the lung and relief of dyspnea and hypoxemia.