What Is Known and Objective Propofol is widely used in painless gastroscopy. However, sedation with propofol alone might increase the risk of respiratory and circulatory complications. This randomized clinical study compares the efficacy and safety of esketamine or dezocine combined with intravenous (IV) propofol in patients undergoing gastroscopy. Methods A total of 102 patients were enrolled in this study and randomized into two groups. All patients were adults aged 18–64 years who underwent upper gastrointestinal gastroscopy. Patients were randomly assigned to two groups to receive esketamine (0.3 mg/kg) combined with propofol (group E) or dezocine (0.05 mg/kg) combined with propofol (group D). In both groups, the drugs were administered intravenously. The primary outcome was the dose of propofol which provided a satisfactory sedative effect, both to the endoscopist and the patients. Secondary outcomes included recovery time, side effects (such as hypotension, nausea and vomiting and agitation), and the number of adverse circulatory and respiratory events. Results Data of 83 patients were analysed in the present study. Dosage of propofol required in group E (1.44 mg/kg ± 0.67 mg/kg) was significantly lower compared with that in group D (2.12 mg/kg ± 0.37 mg/kg) (p < 0.0001). There was no statistically significant difference in recovery time, side effects, and the frequency of sedation‐related adverse events between the two groups. What Is New and Conclusion The study indicates that intravenous injection of propofol and esmketamine is more effective for gastroscopy. Use of esketamine reduces the total amount of propofol required in ASA I–II patients undergoing gastroscopy compared with single use of dezocine. It also provides more stable hemodynamics, without affecting the recovery time and side effects such as respiratory and circulatory adverse events. Trial Registration The study was registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn; registration number: ChiCTR2100051814) on 05/10/2021.

Objective: This study aimed to determine the optimal dose of propofol combined with esketamine to inhibit the response to gastroscope insertion in elderly patients.Methods: This is a prospective, non-controlled, non-randomized, single-center study. Elderly patients aged 65–80 years were enrolled in the study with the American society of anesthesiologists (ASA) physical status I or II undergoing elective gastroscopy. All patients were administered propofol after an intravenous esketamine at the dosage of 0.3 mg/kg 30 s, the subsequent dose of propofol was determined by the response of the previous patient to gastroscope insertion (choking, body movement, etc.) using Dixon’s up-and-down method. The initial dose of propofol administered to the first elderly patient was 3.0 mg/kg, and the standard ratio of propofol dose in adjacent patients was 0.9. At least six crossover points were obtained before the conclusion of the study. By using Probit analysis the median effective dose (ED50), 95% effective dose (ED95), and the corresponding 95% confidence interval (CI) for propofol were determined.Results: The study continued until we obtained seven crossover points and 32 elderly patients (17 males and 15 females) were collected. The ED50 of propofol combined with esketamine inhibiting response to gastroscope insertion in elderly patients were found to be 1.479 mg/kg (95% CI 1.331–1.592 mg/kg), and ED95 was found to be 1.738 mg/kg (95% CI 1.614–2.487 mg/kg).Conclusion: According to the present study, propofol combined with 0.3 mg/kg esketamine is safe and effective for elderly patients undergoing gastroscopy. The ED50 and ED95 doses of propofol inhibiting response to gastroscope insertion in elderly patients when combined with 0.3 mg/kg esketamine were 1.479 and 1.738 mg/kg, respectively, without apparent adverse effects.

What Is Known and Objective. Appropriate doses of sedatives are crucial for a successful, painless upper gastrointestinal endoscopy. Hence, we conducted a randomized controlled study to explore the effects of dezocine on the median effective dose (ED50) of the etomidate-propofol (E-P) mixture in prohibiting response to gastroscope insertion in patients of different genders. Methods. Patients aged 18–65 years enrolled in the study of the American Society of Anesthesiologists (ASA) with physical status I or II undergoing elective gastroscopy were included. Patients were randomly assigned to the male normal saline group (MS group), male dezocine group (MD group), female normal saline group (FS group), and female dezocine group (FD group). All patients were anesthetized with an E-P mixture of 1 : 1. The FD and MD groups were intravenously injected (i.v.) 50 µg/kg dezocine 5 min before anesthesia, while the FS and MS groups were injected with an equal volume of normal saline 5 min before anesthesia. According to the preexperiment, the initial dose of the E-P mixture for the FD and MD groups was 0.4 and 0.3 mL/kg for the FS and MS groups. The variation proportion was set as 0.9 between dosages. Dixon’s up-and-down method was adopted to confirm the dose of the E-P mixture for the next patient, which was reduced if the insertion was performed successfully; otherwise, the dose was increased. Centered isotonic regression was employed to determine the ED50 and 90% confidence interval (CI) values of the E-P mixture in the four groups. The total amount of E-P mixture consumed was recorded as well as the adverse events of patients. Results. The ED50 and 90% CI of the MS, MD, FS, and FD groups were 0.315 (0.285–0.349), 0.206 (0.175–0.237), 0.329 (0.305–0.355), and 0.207 (0.188–0.227) mL/kg, respectively. The MD group was <MS group ( P ≤ 0.001 ), and the FD group was <FS group ( P ≤ 0.001 ); no statistical difference was observed between the MS and FS groups and MD and FD groups. Dezocine reduced the total amount of E-P mixture consumed and the overall incidence of adverse events. What Is New and Conclusion. Dezocine significantly decreased the ED50 of the E-P mixture in inhibiting the response of patients to gastroscope insertion and the occurrence rate of adverse events. Further, gender had no impact on the ED50 of the E-P mixture.