Utilizing nasal‐tragus length to estimate optimal endotracheal tube depth in neonates: A prospective randomized control study

Background Determination of the optimal depth of endotracheal tube insertion in neonates is challenging. Various formulae have been proposed and are being commonly used for this purpose. There is no single formula that is ideal or can be applied across different populations. Aim To compare weight and nasal‐tragus length‐based formulae as a guide to endotracheal tube insertion depth in term neonates undergoing surgery. Ther primary objective of the study was to determine the position of the endotracheal tube using either weight‐based or nasal‐tragus length‐based formulae and the secondary objective was to determine the incidence of repositioning of the endotracheal tube. Methods A total of 120 full term neonates were divided into two groups with 60 neonates each (group N = NTL + 1 cm and group W = Weight + 6 cm). Endotracheal tube was inserted according to the pre‐calculated value and fixed. A neonatal flexible fiberoptic bronchoscope was used to confirm the position of the endotracheal tube tip by measuring its distance from the carina. Repositioning was done if the distance from carina to endotracheal tube tip was less than 20 mm. Chi‐squared and Mann–Whitney tests were used for the analysis. Results The mean distance measured from carina to endotracheal tube tip in group N was 9.41 ± 6.65 mm and in group W was 3.21 ± 3.45 mm (p value =