Learning curve of fiber-optic orotracheal intubation guided by the nasopharyngeal airway in anesthetized patients

Background: Flexible orotracheal intubation poses a challenge for novice trainees owing to its comparatively low success rate. It is hypothesized that the preplacement of a Nasopharyngeal Airway (NPA) could serve as a guide for the fiber-optic bronchoscope,to enhance the likelihood of successful intubation. Methods: Sixteen novice anesthesia trainees were divided into either a guidance group (G group) or a conventional group (C group), with eight trainees in each cohort. Each participant conducted 20 consecutive intubation attempts on anesthetized patients undergoing elective procedures. In the G group, an NPA was prepositioned, and trainees were instructed to locate its tip to guide the flexible fiber-optic bronchoscope towards the glottis during intubation. Conversely, in the C group, trainees performed conventional fiber-optic orotracheal intubation directly following anesthesia induction. The primary outcome assessed was the rate of successful first-attempt intubation, while secondary outcomes included time to glottis exposure, intubation duration, trainee learning curve, and airway-related complications. Results: The comparative analysis indicated that novice residents from the G group demonstrated a significantly higher success rate of first-attempt orotracheal intubation using a flexible fiber-optic bronchoscope, reduced times of glottis exposure and intubation, and a steeper learning curve compared to those from the C group (p < 0.05). Moreover, no significant differences in airway-related complications were observed between the groups. Conclusions: The study suggested that the use of a preplaced NPA device as a guide for advancing the fiber-optic bronchoscope significantly improved success rate and enabled novice residents to achieve proficiency in fiber-optic orotracheal intubation in anesthetized patients with normal airways.