Clinical Research Directory

Inclusion Criteria:Voluntary acceptance;Asa1-2 level;Age 18-95y;Mallampati grades Ⅰ or Ⅱ Exclusion Criteria: 1. Patients with blood clotting disorders or a tendency to oropharyngeal bleeding, mucosal damage or space occupation, difficulty in placing oropharyngeal airway, etc., who cannot perform oropharyngeal airway ventilation; 2. Severe cardiac insufficiency (\<4mets); 3. Patients with severe renal insufficiency (requiring dialysis before surgery); 4. Diagnosed severe liver insufficiency; 5. Diagnosed with chronic obstructive pulmonary disease (COPD) or currently suffering from other acute or chronic lung diseases, requiring long-term or intermittent oxygen therapy; 6. Increased intracranial pressure; 7. Upper respiratory tract infections such as mouth, nose or throat; 8. Fever (core body temperature \>37.5 degrees Celsius); 9. a confirmed diagnosis of pregnancy or breastfeeding; 10. Allergic to sedatives such as propofol or equipment such as tape; 11. Emergency surgery; 12. Multiple trauma; 13. SpO2 \< 95% in preoperative breathing air;