Low-dose esketamine combined with propofol versus fentanyl-propofol for preventing hypoxemia during gastroscopy sedation in high-altitude residents: a randomized controlled trial.

Objective: The aim of this study is to evaluate the efficacy and safety of low-dose esketamine combined with propofol in reducing the incidence of hypoxemia during deep sedation for painless gastroscopy in patients residing at high altitude Additionally, the study sought to inform the optimization of sedation protocols in hypobaric environments.

Methods: A single-center, double-blind, randomized controlled trial was conducted involving 168 patients residing at an altitude of 3200 m who were scheduled for elective gastroscopy. Patients were randomly assigned to receive either low-dose esketamine (0.2 mg/kg) combined with propofol (experimental group) or fentanyl (1 µg/kg) combined with propofol (control group). The primary outcome was the incidence of hypoxemia, defined as peripheral oxygen saturation < 90% lasting more than 10 s. Secondary outcomes included intraoperative hemodynamic changes, total propofol dosage, and postoperative recovery parameters.

Results: The incidence of hypoxemia was significantly lower in the experimental group compared to the control group (8.75% vs. 32.5%, p < 0.001). Incidences of hypotension (8.8% vs. 23.8%, p < 0.050) and somatic responses (2.5% vs. 12.5%, p < 0.050) were also reduced in the experimental group. The experimental group required a 25.5% lower total dose of propofol (143.1 ± 23.5 mg vs. 192.1 ± 34.1 mg, p < 0.001), achieved a shorter recovery time based on the Aldrete score (7.41 ± 1.61 min vs. 9.63 ± 2.41 min, p < 0.001), and yielded higher operator satisfaction scores (8.69 ± 0.6 vs. 7.79 ± 0.9, p < 0.001). No statistically significant difference was noted between groups regarding the incidence of postoperative nausea and vomiting (2.5% vs. 1.3%, p = 0.560).

Conclusion: Low-dose esketamine combined with propofol is associated with a significantly lower incidence of hypoxemia and improved hemodynamic stability during gastroscopy sedation in patients residing at high altitude. This regimen also reduces propofol requirements, facilitates more rapid postoperative recovery, and is associated with greater proceduralist satisfaction, indicating its potential utility as a safe and effective sedation strategy in high-altitude clinical environments.

Trial Registration: Full name of the registry: Chinese Clinical Trial Registry.

Trial Registration Number: ChiCTR2500100947. Date of registration: 2025/04/17 (Retrospectively registered).