Risk factors for difficult mask ventilation and difficult intubation among patients undergoing pharyngeal and laryngeal surgery.

Background: The prediction of difficult mask ventilation (DMV) and difficult intubation (DI) are key questions in anesthesia fields. DMV or DI related to pharyngeal and laryngeal diseases are a special kind of difficult airways. However, there is a lack of risk factors for prediction.

Methods: This study retrospectively collected data from patients who were admitted to the Eye & ENT Hospital of Fudan University from May 2014 to May 2018 and underwent laryngopharyngeal surgery under general anesthesia.

Results: A total of 126 patients were included. Twenty patients suffered from DMV. Preoperative laryngeal obstruction classification (OR = 7.46, 95% CI: 2.56-21.76, P < 0.001) and airway patency after sevoflurane inhalation (OR = 10.96, 95% CI: 2.70-44.43, p = 0.001) were independently associated with DMV. Seventy-six patients could be intubated at the first attempt. Preoperative laryngeal obstruction grade (OR = 0.28, 95% CI: 0.13-0.62, P = 0.002), neoplasm size (OR = 0.43, 95% CI: 0.22-0.82, P = 0.011), and airway patency after sevoflurane inhalation (OR = 0.14, 95% CI: 0.05-0.36, P < 0.001) were independently associated with first-attempt successful intubation.

Conclusion: Among patients with pharyngeal and laryngeal diseases, the degree of laryngeal obstruction before the operation and the degree of airway obstruction after inhaling sevoflurane are the risk factors of DMV. The degree of laryngeal obstruction before the operation, airway obstruction after inhaling sevoflurane, and the neoplasm size are the risk factors of DI.