Feasibility and Safety of Supraglottic Oxygen Delivery Via an Endotracheal Tube for Non-intubated ERCP Anesthesia: A Two-Stage Phase II Clinical Study

Inclusion Criteria: * Age ≥18 years； * The ASA classification ranges from I to III. * Patients have signed the informed consent form. * Patients scheduled to undergo sedated ERCP examination; * The estimated duration of the procedure does not exceed 45 minutes. Exclusion Criteria: * Severe cardiac dysfunction (\<4 METs); * Severe renal insufficiency (requiring preoperative dialysis); * Diagnosed chronic obstructive pulmonary disease (COPD) or other acute/chronic pulmonary diseases requiring long-term/intermittent oxygen therapy; * Increased intracranial pressure; * Upper respiratory tract infections (oral/nasal/pharyngeal); * Fever (core temperature \>37.5°C); * Confirmed pregnancy or current breastfeeding; * Allergy to sedatives (e.g., propofol) or medical adhesives; * BMI \>30 kg/m²; * Current participation in other clinical trials;