This study aims to explore the clinical effect of THRIVE in improving early postoperative atelectasis in patients undergoing long-term non-intubated anesthesia gastrointestinal endoscopy.

Inclusion Criteria:

1. Multiple polyps resection, ESD(Endoscopic Submucosal Dissection) , EMR(Endoscopic Mucosal Resection), enteroscopy and other gastrointestinal endoscopic diagnosis and treatment were performed
2. The duration of anesthesia is more than 30 minutes, that is, from induction to withdrawal of anesthesia
3. ASA(American Society of Anesthesiologists) ≤ II 4.18kg/m2<BMI<30 kg/m2

5.Informed consent, voluntary participation in the experiment, and signed by the subject informed consent

Exclusion Criteria:

1. ASA classification ≥ III;
2. History of previous lung or nasal surgery;
3. History of chronic obstructive pulmonary disease (COPD) or restrictive lung disease;
4. History of obstructive sleep apnea syndrome;
5. History of upper airway obstruction;
6. History of head and neck radiation therapy;
7. Significant nasal septum deviation;
8. Active infection (defined as a white blood cell count >10*10^9 or a body temperature >38°C);
9. Gastrointestinal perforation;
10. Combined use of other anesthetic methods or inhalation anesthetics outside of non-intubated intravenous anesthesia;
11. Concurrent other medical procedures besides the prescribed gastrointestinal endoscopic procedures, such as ERCP(Endoscopic Retrograde Cholangiopancreatography);
12. Severe communication disorders due to conditions like severe hearing impairment or dementia;
13. Disagreement with participation in the study.