A Randomised Control Study Comparing Ultrasonography with Standard Clinical Methods in Assessing Endotracheal Tube Tip Positioning.

Introduction: Airway ultrasound has been increasingly used in correct positioning of endotracheal tube. We hypothesize that a safe distance between endotracheal tube tip and carina can be achieved with the aid of ultrasound.

Aim of the study: Our primary objective was to determine whether ultrasound guided visualisation of proximal end of endotracheal tube cuff is better when compared to conventional method in optimal positioning of tube tip. The secondary objective was to find the optimal endotracheal tube position at the level of incisors in adult Indian population.

Materials and methods: There were 25 patients each in the conventional group and the ultrasound group. Conventional method includes auscultation and end tidal capnography. In the ultrasound group the upper end of the endotracheal tube cuff was positioned with an intent to provide 4 cm distance from the tube tip to the carina. X ray was used in both groups for confirmation of tip position and comparison between the two groups. Further repositioning of the tube was done if indicated and the mean length of the tube at incisors was then measured.

Results: After x ray confirmation, endotracheal tube repositioning was required in 24% of patients in the USG group and 40 % of patients in the conventional group. However, this result was not found to be statistically significant (p = 0.364). The endotracheal tube length at the level of teeth was 19.4 ± 1.35 cm among females and 20.95 ± 1.37 cm among males.

Conclusions: Ultrasonography is a reliable method to determine ETT position in the trachea. There was no statistically significant difference when compared to the conventional method. The average length of ETT at the level of incisors was 19.5 cm for females and 21 cm for males.