Measuring Endotracheal Tube Depth by Bedside Ultrasound in Adult Patients in an Intensive Care Unit: A Pilot Study

Ultrasound Med Biol. 2017 Jun;43(6):1163-1170. doi: 10.1016/j.ultrasmedbio.2017.01.018. Epub 2017 Mar 17.


The aim of the study described here was to evaluate the feasibility and accuracy of measuring endotracheal tube (ETT) depth with ultrasound in adult patients in an intensive care unit (ICU). The distance between the upper margin of the cuff and the upper margin of the aortic arch (Duc-ua) of 67 ICU patients was measured by ultrasound, and the time of measurement was recorded. The level of agreement between the distance between the tip of the ETT and the carina (Dtt-c) measured by ultrasound (U-Dtt-c) and Dtt-c measured by bronchoscopy (B-Dtt-c) was assessed using linear regression and a Bland-Altman plot. There was a significant correlation between B-Dtt-c and U-Dtt-c (r = 0.844, p < 0.001). Also, the Bland-Altman plot revealed strong agreement between B-Dtt-c and U-Dtt-c. The time it took to measure ETT depth by ultrasound was 33.91 ± 5.43 s. In conclusion, bedside ultrasound provides a novel and convenient method for measuring the depth of ETT in ICU patients.

Keywords: Bronchoscopy; Computed tomography scan; Critical care; Endotracheal intubation; Endotracheal tube; Point-of-care ultrasound.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anatomic Landmarks / diagnostic imaging
  • Aorta, Thoracic / diagnostic imaging*
  • Critical Care / methods*
  • Feasibility Studies
  • Humans
  • Intensive Care Units
  • Intubation, Intratracheal / instrumentation*
  • Intubation, Intratracheal / methods*
  • Pilot Projects
  • Point-of-Care Systems*
  • Reproducibility of Results
  • Retrospective Studies
  • Sensitivity and Specificity
  • Trachea / diagnostic imaging*
  • Ultrasonography, Interventional / methods*