The factors influencing bronchoscope passing through the glottis

Background: Flexible bronchoscopy is an important procedure in respiratory diseases. It is crucial whether bronchoscope can successfully pass through the glottis. The aims of the study were evaluation of differences between bronchoscope successfully passing through the glottis at one-time and repeatedly insertion at times, and analysis of various factors associated with failure of bronchoscope passing through the glottis. Methods: A retrospective analysis was performed from March 2019 to May 2019, in consecutive patients who had undergone diagnostic flexible bronchoscopy. The patients were divided into two groups according to the condition of bronchoscope passing through the glottic. Demographic and clinical information collected included age, gender, body mass index, respiratory disease, patient position, procedural time, cough and bleeding of nasal mucosa. We also recorded vital signs, including pre-, intra- and post-procedure of bronchoscope passing through the glottis. Results: 153 patients were in success group and 47 were in failure group. Success group was average 4 seconds shorter than the failure group (P = 0.001). Meanwhile, repeated passing through glottis was associated with an increase in the bleeding of nasal mucosa and cough. On the multivariate logistic regression, the neutral position and cough were the two factors associated with a higher risk of failure of passing through the glottis. Conclusions: In conclusion, successfully passage through the glottis can save procedural time and decrease the rate of cough and bleeding of nasal mucosa. Meanwhile, the neutral position and cough are two risk factors associated with failure to pass through the glottis at one time.