Double-lumen endobronchial intubation-related anatomical factors of respiratory tract in adult patients: measurement of glottis and left main bronchus using computed tomography

Objective To investigate the double-lumen endobronchial intubation-related anatomical factors of respiratory tract in adult patients through measurement of the parameters of glottis and left main bronchus using computed tomography(CT). Methods A total of 206 patients of both sexes, aged 20-80 yr, of American Society of Anesthesiologists physical status Ⅰ-Ⅲ, scheduled for elective surgery, were enrolled in this study.The cervical and thoracic CT images were evaluated.The anteroposterior glottic diameter(AP-GD), anteroposterior tracheal diameter(AP-TD), transverse tracheal diameter(Tr-TD), left and right main bronchus diameters(LBD and RBD)and length between glottis and carina(G-TL)were measured.Multiple linear regression analyses were performed to detect the correlations between obtained parameters and between obtained parameters and height. Results AP-GD was(19±3)mm, AP-TD(20±4)mm, Tr-TD(16.6±2.4)mm, LBD(12.3±2.0)mm, RBD(13.7±2.0)mm and G-TL(126±11)mm.AP-GD, height, AP-TD and Tr-TD were moderately correlated with LBD(r was 0.522, 0.584, 0.648 and 0.606, respectively, P 0.05). Conclusion Tr-TD and AP-GD should be considered besides double-lumen endobronchial intubation-related anatomical factors such as LBD and height in adult patients. Key words: Glottis; Bronchi; Double-lumen endotracheal tube