Comparison of Oxygen Saturation Between Nasal High-Flow Oxygen and Conventional Nasal Cannula in Obese Patients Undergoing Dental Procedures With Deep Sedation: A Randomized Crossover Trial

Purpose: In anesthetic management, it is widely accepted that obese patients are more likely to suffer airway obstructions and reductions in arterial oxygen saturation (SpO₂). Therefore, it is important to take special measures to prevent oxygen desaturation during the deep sedation of obese patients. This clinical study examined whether the use of nasal high-flow systems (NHFS) keep higher SpO₂ and reduced hypoxemia than conventional nasal cannula during the deep sedation of obese patients with intellectual disabilities for dental treatment. Materials and Methods: Eighteen obese patients (body mass index: >25) with intellectual disabilities who underwent dental sedation were enrolled. In each case, sedation was induced using propofol and maintained at a bispectral index of 50 to 70. The subjects were randomly assigned to the control oxygen administration (5 L/min via a nasal cannula) or NHFS (40% O₂, 40 L/min, 37 °C) arm in alternate shifts as a crossover trial. The primary endpoint was the minimum SpO₂ value, and the incidence of hypoxemia during dental treatment was also evaluated. Results: The mean minimum SpO₂ value was significantly higher in the NHFS arm than in the control arm (95.8 ± 2.1 % vs 93.6 ± 4.1 %, P = 0.0052, 95% confidence interval: 0.608-3.947). Hypoxemic episodes (SpO₂: ≤94%) occurred 3 cases (16.7%) in the NHFS arm and 11 cases (61.1%) in the control arm (P = 0.0076, odds ratio: 0.127, 95% confidence interval 0.0324 - 0.630). Conclusion: NHFS resulted in higher minimum SpO₂ and reduced hypoxemia than nasal cannula in obese patients during deep sedation for dental treatment.