To evaluate the accuracy of air column width difference(ACWD)between inflation and deflation of the cuff of the endotracheal tube(ETT)in predicting post-extubation stridor(PES).

A total of 102 intubated patients of both sexes and all ages, who were mechanically ventilated for ≥24 h in the intensive care unit, of American Society of Anesthesiologists physical status Ⅲ or Ⅳ, were enrolled in the study.After the patients were in a stable condition and recovered consciousness and myodynamia, they were weaned from the ventilator, and ultrasound examination of the larynx was performed to determine ACWD between ETT cuff inflation and deflation.PES was assessed using blinding method after extubation, and the patients were divided into 2 groups depending on whether or not the patients developed PES: PES group(group P)and non-PES group(group N).

There were 94 patients in group N and 8 patients in group P. Compared with group N, ACWD was significantly decreased in group P(P<0.05). The cut-off value of ACWD determined by the receiver operating characteristic curve was 1.65 mm, the sensitivity and specificity of ACWD were 0.830 and 0.750, respectively, and the area under the receiver operating characteristic curve was 0.801.

For the intubated patients who are mechanically ventilated for ≥24 h in an intensive care unit, ACWD between ETT cuff inflation and deflation<1.65 mm can effectively predict PES.

Respiration, Artificial; Respiratory sounds; Laryngeal air column width difference