Supplementary Material for: Estimation of Optimal Nasotracheal Tube Insertion Depth in Neonates Based on Fetal Biometric Measurements

Background: Current recommendations for neonatal endotracheal tube (ETT) insertion depths require the knowledge of anthropometric measurements, which are not immediately available in the delivery room setting. Objective: This study aimed to develop recommendations based on prenatally available fetal biometric measurements. Methods: In this retrospective study, the optimal ETT depths for nasotracheal insertion were correlated with fetal demographic and biometric data. Using linear regression analysis, diagrams with best-fit lines and tables for the recommendation of ETT insertion depth based on the prenatally available data were generated. Results: We analyzed optimal nasotracheal ETT insertion depth in 98 neonates (gestational age range: 23.7–42.0 weeks). Linear regression analysis revealed high correlations between fetal measurements and the optimal ETT insertion depth (R2 = 0.712–0.837). Conclusion: We provide recommendations for neonatal nasotracheal ETT insertion depths based on prenatally available data with the potential to facilitate rapid and accurate intubation of neonates.