Mediastinal mass and tracheal obstruction during general anesthesia.

A 24-year-old man had a large anterior mediastinal mass and a nonproductive cough of 6 weeks' duration. With the patient under general anesthesia, a diagnostic mediastinoscopy was performed with endotracheal intubation. During the procedure, acute respiratory failure developed as a result of tracheal obstruction. Fiberoptic bronchoscopic examination of the patient in the supine position revealed almost total extrinsic compression of the trachea and no evidence of intraluminal disease. Reexamination of the trachea with the patient in sitting and semiprone positions showed resolution of the extrinsic compression and respiratory distress. Flow-volume curves obtained before treatment of the mediastinal mass (histologically diagnosed as Hodgkin's lymphoma) disclosed major airway compression with the patient in the supine position; the abnormality disappeared after chemotherapy. The mechanisms responsible for tracheal compression by mediastinal masses during general anesthesia may include the following: (1) the effect of anesthesia on pulmonary mechanics, (2) the supine body position, (3) the elimination of glottic regulation of airflow by endotracheal intubation, (4) changes related to the surgical manipulation of the tumor itself, (5) the size and location of the mediastinal mass, (6) the young age of the patient, and (7) preexisting airways disease. Anticipation and prevention of potential respiratory complications and preparedness to treat them appropriately are important aspects of the management of these patients.