The trachea of a 74-year-old man undergoing left pneumonectomy could not be intubated in two attempts after induction of anesthesia with midazolam, fentanyl, propofol and rocuronium. Difficult intubation had not been foreseen, but inspection through the laryngoscope revealed Cormack and Lehane grade IV conditions. Because a small-caliber fiberoptic bronchoscope was unavailable for intubation with a double-lumen endobronchial tube, we inserted a No. 9 orotracheal tube with a 6 mm bronchoscope as far as the left main bronchus. Intubation was aided by a universal adaptor for fiberoptics with a face mask and a Williams cannula. We were then able to ventilate the patient manually with 100% oxygen during bronchoscopy. As selective ventilation was required during surgery, a No. 11 Cook-type airway exchange catheter was inserted into the left main bronchus, the tracheal tube was removed, and was used to guide a No. 39F left double-lumen endobronchial tube through the bronchus. Insertion was uncomplicated and selective ventilation was satisfactory. The technique described is a new application for the Cook exchange catheter that allows selective bronchial in difficult cases when a small-caliber fiberoptic bronchoscope is unavailable.