Ultrasound-guided lung sliding sign to confirm optimal depth of tracheal tube insertion in young children

Background: The tip of the tracheal tube should lie at the mid-tracheal level after tracheal intubation in paediatric patients. Auscultation does not guarantee optimal positioning of the tracheal tube. We compared auscultation and the ultrasound-guided lung sliding sign to confirm optimal positioning of the tracheal tube in paediatric patients. Methods: We studied 74 paediatric patients aged 0–24 months of ASA physical status 1–3 who were scheduled for elective surgery under general anaesthesia. All were randomly assigned to one of two groups: depth of tracheal tube confirmed by auscultation (Group A) or using the ultrasound-guided lung sliding sign (Group S). Results: Optimal positioning of the tracheal tube was observed in 32 of 37 (87%) subjects in Group S and 24 of 37 (65%) subjects in Group A (difference in proportion, 22%; 95% confidence interval, 2–39%; P=0.030). Optimal depth correlated with patient height (adjusted coefficient=0.888, P<0.001). Conclusions: In paediatric patients younger than 24 months, use of the ultrasound-guided lung sliding sign was more accurate than auscultation for optimal positioning of the tracheal tube. Clinical trial registration: KCT 0003015.