RESUMO
PURPOSE: To investigate the optimal agent combined with propofol for sedation in elderly patients undergoing gastrointestinal endoscopy. METHODS: A total of 120 elderly patients scheduled for gastrointestinal endoscopy under propofol-based sedation were randomly allocated to receive propofol + saline (control group), propofol + sufentanil 0.1 µg/kg, propofol + dexmedetomidine 0.4 µg/kg, or propofol + ketamine 0.4 mg/kg. Mean arterial pressure, heart rate, pulse oximetry, pressure of end-tidal carbon dioxide, respiratory rate, and Ramsay sedation scale score were recorded. Induction time, procedure time, recovery time, propofol dose, and adverse events were also recorded. FINDINGS: During the sedation procedure, the AUC of HR was lowest in the propofol + dexmedetomidine group (all, P < 0.05), and the AUC of pulse oximetry was significantly higher in the propofol + dexmedetomidine and propofol + ketamine groups compared to the other 2 groups (both, P < 0.05). The propofol + dexmedetomidine group had the highest prevalences of hypotension and bradycardia, and the control group experienced the largest number of hypoxia episodes (all, P < 0.05). The control group consumed the highest dose of propofol, while the propofol + ketamine group needed the lowest dose (all, P < 0.05). IMPLICATIONS: The combination of propofol + ketamine 0.4 mg/kg maintained hemodynamic and respiratory stability, as evidenced by less hypotension, bradycardia, and hypoxia events, in elderly patients undergoing gastrointestinal endoscopy. China clinical trial registration (chictr.org.cn) ID: ChiCTR-INR-17013710.