Left bronchial intubation by a single-lumen tube in adults: effects of bevel and curvature.

This study was designed to determine whether left bronchial intubation could be accomplished by reversal of the direction of the bevel or by changing the direction of curvature of a normal tracheal tube. The 60 study patients were divided into three groups. In group 1, the patients were intubated in the usual manner, with bevel to the left and the tube concave anteriorly. In group 2, the normal tracheal tube was rotated 90 degrees counterclockwise during insertion. In group 3, the bevel of the tracheal tube was altered to face the right, with the tube still concave anteriorly. In group 1, all 20 tracheal tubes entered the right primary bronchus. In group 2, 14 tracheal tubes (70%) entered the left primary bronchus. In group 3, 18 tubes entered the right primary bronchus and 2 entered the left. The position of the bevel did not influence the positioning of the tracheal tube in the right or left bronchus. In summary, 90 degrees counterclockwise rotation from the usual position and altering the concavity of the tube to face the left significantly increased the likelihood of intubation of the left primary bronchus.