Combination of COMBO Endoscopy Oropharyngeal Airway and HFNC Oxygenation in Sedated Gastrointestinal Endoscopy for Morbidly Obese Patients

Inclusion Criteria:

* Age ≥ 18 years.
* BMI ≥ 35 kg/m².
* Patients undergoing gastroscopy or gastrointestinal endoscopy.
* The estimated duration of the procedure does not exceed 45 minutes.
* Patients have signed the informed consent form.

Exclusion Criteria:

* Coagulation disorders or bleeding tendency (e.g., oral/nasal bleeding risk, mucosal injury, oropharyngeal obstruction) making oropharyngeal airway placement unsafe or unfeasible.
* Active upper respiratory tract infection (oral, nasal, or pharyngeal), or fever (core temperature \>37.5°C).
* Chronic obstructive pulmonary disease or other acute/chronic pulmonary diseases requiring long-term or intermittent oxygen therapy, or preoperative SpO₂ ≤ 92% on room air.
* Severe organ dysfunction, including: Cardiac insufficiency (\<4 METs), Severe renal insufficiency (requiring dialysis), Diagnosed severe hepatic insufficiency, Increased intracranial pressure, ASA physical status ≥ IV.
* Confirmed pregnancy or current breastfeeding.
* Known allergy to sedatives (e.g., propofol) or medical adhesives.
* Multiple traumatic injuries.
* Current participation in another clinical trial.
* Other conditions deemed unsuitable by the investigator.