Objective: To determine if there is a relationship between tracheal width (TW) and left bronchial width (LBW).
Design: Three-dimensional chest computed tomography (CT) scans were used to reconstruct major airways for measurement of TW and LBW.
Setting: Stanford University Medical Center, Stanford, California.
Participants: Thirty-one adult patients undergoing chest CT scans.
Interventions: Cursors were used to directly measure internal diameter from coronal images of the trachea at midclavicular level and the left main bronchus at a level 1 cm below the carina.
Measurements and main results: TW and LBW, but not the LBW-to-TW ratio, were significantly larger in men than in women. The LBW-to-TW ratio was consistent for men (0.75 +/- 0.09) and women (0.77 +/- 0.10).
Conclusions: LBW is proportional to TW. If LBW cannot be measured directly but TW can, the ratio of LBW to TW can be used to predict LBW. An appropriate-sized left double-lumen tube can then be selected for the patient.
Copyright 2001 by W.B. Saunders Company