Difficult 32-Fr Double-Lumen Tube Intubation in a Small Japanese Woman With Narrow Transverse Width of the Cricoid Cartilage.

We encountered difficulty in inserting a 32-Fr left double-lumen tube (DLT) in a small 75-year-old Japanese woman (height, 144 cm). The 32-Fr DLT with 10.1 × 11.2-mm tracheal diameter could not pass through the cricoid cartilage with a 9.2-mm transverse inner width. The transverse inner width of the cricoid cartilage, in addition to the tracheal and bronchial diameter, can be measured using computed tomography or ultrasonography in small women. Thus, a 28-Fr DLT or single-lumen tube and a blocker can be selected instead of a 32-Fr DLT when the width of the cricoid cartilage is <10 mm.