Subglottic jet ventilation versus supraglottic jet ventilation for flexible bronchoscopy: a randomized controlled trial.

BACKGROUND: Jet ventilation technique can be used to supply oxygen to prevent hypoxia for patients undergoing flexible bronchoscopy. An optimal access route for jet ventilation technique during flexible bronchoscopy has not been determined. Our aim was to compare the effectiveness and safety of subglottic jet ventilation via a new introducer (Safe Easy Endotracheal Kit-flexible, SEEKflex) versus supraglottic jet ventilation via Wei nasal jet tube in patients undergoing flexible bronchoscopy under moderate-to-deep sedation. METHODS: This was a single-center randomized controlled trial. 352 patients scheduled to undergo flexible bronchoscopy under moderate-to-deep sedation were randomly assigned to the following two groups: the subglottic jet ventilation group, and the supraglottic jet ventilation group. The primary outcome was hypoxia during flexible bronchoscopy. RESULTS: Subglottic jet ventilation decreased the incidence of hypoxia from 16.6% to 6.0% compared with supraglottic jet ventilation [relative risk (RR) for hypoxia, 0.364, 95% CI 0.18 to 0.72; P 0.002]. The incidence of severe hypoxia was also significantly diminished in the subglottic jet ventilation group compared with the supraglottic jet ventilation group (3% vs. 8.6%; RR 0.351, 95% CI 0.12 to 0.95; P 0.030). The subglottic jet ventilation group needed significantly less jaw thrust (4.8% vs. 12.9%; RR 0.374, 95% CI 0.17 to 0.82; P 0.010), and mask ventilation (2.4% vs. 7.4%; RR 0.327, 95% CI 0.10 to 0.99; P 0.037). No gastric insufflation occurred in the subglottic jet ventilation group, 31 instances occurred in the supraglottic jet ventilation group (P < 0.001). There was no significant difference between the two groups in terms of other adverse events including xerostomia, pharyngalgia, nasal bleeding. CONCLUSIONS: Subglottic jet ventilation more effectively reduces the incidence of hypoxia in patients undergoing flexible bronchoscopy under moderate-to-deep sedation when compared with supraglottic jet ventilation. Subglottic jet ventilation via the SEEKflex may be a preferable approach. TRIAL REGISTRATION: ChiCTR2300076139.