Prediction of endotracheal tube size using a printed three-dimensional airway model in pediatric patients with congenital heart disease: a prospective, single-center, single- group study.

Park, Seyeon; Ahn, Jisoo; Yoon, Sung Uk; Choo, Ki Seok; Kim, Hye-Jin; Chung, Minwoo; Kim, Hee Young

Background To determine the correct size of endotracheal tubes (ETT) for endotracheal intubation of pediatric patients, new methods have been investigated. Although the three-dimensional (3D) printing technology has been successful in the field of surgery, there are not many studies in the field of anesthesia. The purpose of this study is to evaluate the accuracy of a 3D airway model for prediction of the correct ETT size, and compare the results with a conventional age-based formula in pediatric patients. Methods Thirty five pediatric patients under 6 years of age who were scheduled for congenital heart surgery. In the pre-anaesthetic period, the patient's computed tomography (CT) images were converted to STL (Standard Triangle Language) files using the 3D conversion program. An FDM (Fused Deposition Modelling) type 3D printer was used to print 3D airway models from the sub-glottis to the upper carina. ETT size was selected by inserting various sized cuffed-ETTs to a printed 3D airway model. Results The 3D method selected the correct ETT size in 21 out of 35 pediatric patients (60%), whereas the age-based formula selected the correct ETT size in 9patients (26%). Conclusions Prediction of correct size ETTs using a printed 3D airway model has demonstrated better results than the age-based formula. In particular, the selection of ETT size using a printed 3D airway model may be feasible for helping minimize re-intubation attempts and complications in the patients with congenital heart disease or an abnormal range of growth and development.