Congenital tracheal bronchus: the inability to isolate the right lung with a univent bronchial blocker tube.

Tracheal bronchus is a congenital anomaly in which the right upper lobe bronchus originates from the lateral tracheal wall. This anatomic variant is reported in approximately 1 of 250 patients at bronchoscopy. Although it is usually of little clinical significance, this atypical origin of the right upper lobe bronchus may complicate one-lung ventilation during thoracic surgery.