General anesthesia was induced with the patient in the supine position. She was intubated with a 7.5 mm ID endoctrachial tube with some difficulty due to a very anterior larynx. Difficulty in ventilating was noted immediately with peak inspiratory pressures of up to 35 cm H20. Endotracheal tube placement was confirmed by mass spectrometry and auscultation revealed decreased breath sounds on the left. Withdrawal of the endotracheal tube did not improve the breath sounds over the left hemithorax. Arterial blood gas determinations revealed a large alveolai^arterial gradient (Pa02, 111 mm Hg; PaC02, 43 mm Hg; pH, 7.30; with an Flo2 of 1.0.

Chest x-ray film (Fig 2) at this time revealed left lower lol>e collapse and marked extrinsic compression at the carinal level. Fiberoptic bronchoscopy revealed marked widening of the carina and compression of both main-strem bronchi with the right main-stem bronchus reduced to 7 mm and the left main-stem bronchus reduced to 5 mm. The left bronchial tree was also partially occluded by thick secretions. These were aspirated and both left upper and lower lobe bronchi were patent. Because ventilation was Incoming increasingly difficult and our concern that turning to the left lateral position might further compromise the lumen of the left main-stem bronchus, decompression of the cyst via flexible bronchoscopy was indicated. A 21-gauge needle was passed through the working channel of the bronchoscope and 60 ml of viscous clear amber fluid was removed. Following aspiration, bronchoscopy revealed the left main-stem bronchial lumen to Ik? 9 mm and ventilation was much improved.

Figure 2. Left lower lobe collapse and marked extrinsic compression at the carinal level have become evident.