Incidence of and risk factors for difficult ventilation via a supraglottic airway device in a population of 14,480 patients from South-East Asia.

Difficult airway practice guidelines include the use of a supraglottic airway device as part of the armamentarium to provide and maintain ventilation and oxygenation. We retrospectively reviewed 14 480 patients aged ≥ 18 years who underwent general anaesthesia. We identified 74 (0.5%) patients whose lungs were identified as having been difficult to ventilate via a supraglottic airway device, and 29 (0.2%) patients in whom device placement failed. Multivariate analysis identified four risk factors for difficult ventilation via a supraglottic airway device: male sex (OR 1.75, 95% CI 1.07-2.86, p = 0.02); age > 45 years (OR 1.70, 95% CI 1.01-2.86, p = 0.04); short thyromental distance (OR 4.35, 95% CI 2.31-8.17, p < 0.001); and limited neck movement (OR 2.75, 95% CI 1.02-7.44, p = 0.04). Adverse respiratory events including oxygen desaturation, hypercapnoea, laryngospasm, and bronchospasm occurred in 17 patients (22%). The incidence of difficult ventilation via a supraglottic airway device was 0.5% in a large cohort of South-East Asian patients.