Study design and patients
This randomized, double-blinded and controlled study was approved by the Committee on Ethics of Biomedicine Research, Shidong Hospital in Shanghai and was also registered in Chinese Clinical Trial Registry ChiCTR2100042252 prior to its start. A total of 90 ASA I-III elderly patients undergoing gastrointestinal endoscopy from November, 2020 to March, 2021, aged 65-89 years, were enrolled in this study and patients’ consents were signed before the endoscopic procedures. In our gastrointestinal endoscopy center, as a routine, each patient undergoes both gastroscopy and colonoscopy under one anesthesia experience.