Study on prevention of hypercapnia by Nasal High Flow in patients with endoscopic submucosal dissection during intravenous anesthesia

Interventions: NHF intervention
Primary outcome(s): 1) Occurrence of marked hypercarbonemia showing maximum value of percutaneous carbon dioxide concentration over 60 mmHg (equivalent to PaCO2> 55 mmHg) during intravenous anesthesia
2) Area under curve (AUC) of percutaneous carbon dioxide concentration per unit time at intravenous anesthesia
3) Duration of moderate hypercarbonemia showing maximum value of 50mmHg or more (equivalent to PaCO2> 45mmHg) during percutaneous anesthesia with intravenous anesthesia
4) Occurrence of hypoxemia showing 90% or less of the value of percutaneous oxygen saturation during intravenous anesthesia
Study Design: randomized controlled trial, open(masking not used), no treatment control/standard of care control, parallel assignment, treatment purpose