New Formula for Depth of Insertion of Endotracheal Tube in Children: A Prospective Observational Study.

Objectives: To assess the correct placement of endotracheal tube (ETT) by confirming it with a flexible fiberoptic bronchoscope (FOB), to propose a new formula that would be suitable for Indian children, and to assess the movement of the ETT tip during neck flexion and extension.

Methods: A total of 76 patients were included in the study between the age of 2 and 10 y. Depth of ETT insertion was assessed using FOB. ETT migration due to changes in head and neck position was also assessed.

Results: It was observed that 6 out of 76 children had endobronchial/at carina position of ETT after the initial insertion as per the black line guidance in the neutral position. While the incidence was 23, 36, and 36, respectively as per Cole, weight-, and height-based formula.

Conclusion: The existing formulae are not suitable for Indian children as their physical stature is different from other ethnic populations. Therefore, the authors suggest a new formula [(Age/2) + 10 cm] for depth of ETT insertion for children of the authors' geographical area.

Trial Registration: CTRI/2015/06/005871.