A novel nasal cannula versus conventional face mask for preventing hypoxemia during flexible bronchoscopy in children: a randomized controlled trial

Maintaining adequate oxygenation during pediatric bronchoscopy is critical for patient safety and procedural success. This study evaluates a novel supraglottic oxygen delivery technique designed to improve intraoperative oxygenation via a less invasive, more efficient approach. In this single-center, prospective, randomized controlled trial, children undergoing elective bronchoscopy were randomly assigned to receive oxygen through a novel nasal cannula (NNO) or conventional face mask (CMO), using computer-generated allocation sequences with concealed envelopes. The primary outcome was intraoperative hypoxemia (SpO₂ 10 s). Secondary outcomes included minimum SpO₂, severe hypoxemia (SpO₂ < 80%), frequency of mask ventilation due to desaturation, operator satisfaction with airway access and visual field, and time to first hypoxemic episode. Safety was assessed by comparing adverse event rates. In the intention-to-treat analysis of 199 randomized children, the incidence of hypoxemia was significantly lower in the NNO group than in the CMO group (6.0% vs. 18.2%; RR = 0.33, 95% CI 0.14–0.80; p = 0.008). Per-protocol analysis yielded consistent results (5.1% vs. 20.5%; p = 0.001). After multivariable adjustment, NNO remained a significant independent protective factor against hypoxemia (aOR = 0.272, 95% CI 0.098–0.753; p = 0.012). Secondary outcomes also favored NNO: lowest recorded SpO₂ was higher (94.9% vs. 93.5%, p = 0.003), mask interventions were fewer (2 vs. 13, p = 0.005), and time to hypoxemia was significantly prolonged (aHR = 0.203, 95% CI 0.075–0.547; p = 0.002). Conclusion: In children with American Society of Anesthesiologists (ASA) physical status I–II undergoing flexible bronchoscopy, the novel nasal cannula was more effective than the conventional face mask in preventing hypoxemia and reducing procedural interruptions. Trial registration: The Chinese Clinical Trial Registry (chiCTR.gov): No. ChiCTR2500113734, Retrospectively registered, Date of registration: December 2, 2025.