Summary: In a randomised trial in obese or OSA patients having propofol-sedated gastroscopy, nasal mask oxygenation cut hypoxemia from 32.8% to 8.5% and severe hypoxemia from 13.8% to 1.7% compared with standard nasal cannula, without increasing other adverse events.
PICO Summary
| Element | Detail |
|---|---|
| Population | 120 adults (18–70) with obesity or obstructive sleep apnea undergoing propofol-sedated gastroscopy. |
| Intervention | Nasal mask oxygenation during the procedure (Group M). |
| Comparison | Standard nasal cannula oxygenation (Group C). |
| Outcome | Hypoxemia fell 32.8%→8.5%, subclinical respiratory depression 48.3%→20.3%, and severe hypoxemia 13.8%→1.7% (all p<0.001), with no increase in other sedation-related adverse events. |
Nasal mask vs cannula in sedated gastroscopy
RCT · obesity/OSA · propofol gastroscopy
Nasal mask oxygenation cut hypoxemia roughly fourfold versus nasal cannula in high-risk patients, with no rise in other adverse events.
Expert Commentary
This is a clean, mechanistically sensible result with a large effect size, and I read it positively. The logic is sound: a nasal mask provides positive pressure that stents the collapsible pharynx open, addressing the actual problem in obese and OSA patients under propofol, airway obstruction and hypoventilation, rather than merely flooding the upper airway with oxygen that cannot reach the alveoli. The reduction in subclinical respiratory depression, not just frank desaturation, suggests genuinely improved ventilation and a safety margin before saturation drops. My caveats are modest: it is a single-centre trial of 120 patients, and an unblinded oxygenation study always carries some risk of differential sedation depth between arms, so device and pressure details matter for reproducibility. Can I use this with my patients? Indirectly but usefully. As an endocrinologist I am not running the sedation, but this reinforces something I can act on, identifying and flagging obese or OSA patients before sedated endoscopy, using STOP-BANG screening, and advocating that high-risk patients receive mask-based rather than cannula oxygenation. It is a low-cost change with a plausibly large safety payoff worth confirming in multicentre data.
References
Yan W, Yan L, Meng W, et al. Effect of nasal mask oxygenation on incidence of hypoxemia during gastroscopy with propofol sedation in patients at risk of hypoxemia: a prospective randomized controlled study. BMC Anesthesiol. 2025;25(1):366. doi:10.1186/s12871-025-03245-1