Prediction Of Pediatric Endotracheal Tube Size By Measuring The Subglottic Diameter Under Ultrasound

Objective:To evaluate the clinical effect of measuring pediatric subglottic diameter under ultrasound for the endotracheal tube size selection in a pediatric population.Methods:The research included two steps.The first step was about the uncuffed endotracheal tube.A total 45 pediatric patients who were scheduled for surgery and undergoing tracheal intubation were enrolled.The second step was about the cuffed endotracheal tube.And 40 pediatric patients were enrolled in this step.In the study,tube size was selected according to subglottic diameter,determined by ultrasound.Tube size was then replaced as necessary until a good clinical fit was obtained.At the same time,calculate a tube size according to the age-based formula.Compared with the age-based formula,the accuracy of measuring the subglottic diameter under ultrasound was analyzed.We also did the correlation analysis between different factors,which included the age,height,weight and the subglottic diameter,and the optimal tube size(ID)separately.At last,the accuracy of this method used for cuffed and uncuffed endotracheal tube size was analyzed.Results:For the uncuffed endotracheal tube,the accuracy of assessing subglottic diameter under ultrasound,which is 89%,is better than the age-based formula,which is 51%.The difference was statistically significant(P<0.05).For the cuffed endotracheal tube,the accuracy of assessing subglottic diameter under ultrasound,which is 80%,is better than the age-based formula,which is 35%.The difference was also statistically significant(P<0.05).The subglottic diameter has a strong correlation with ID than other factors in both steps.The difference between the accuracy of the uncuffed endotracheal tube selected by ultrasound and the cuffed endotracheal has no mean.Conclusion:Predicting the uncuffed and cuffed endotracheal tube size according to subglottic diameter,determined by ultrasound,is a new simple way in the clinical.