Efficacy and Safety of Different Esketamine Doses Combined with Propofol in Gastrointestinal Endoscopy

This prospective randomized double-blind trial compared the efficacy and safety of 0.3 mg/kg versus 0.5 mg/kg esketamine combined with propofol in 120 young and middle-aged patients (ASA I–II, 20–45 years) undergoing combined gastroscopy and colonoscopy. Participants were randomized to 0.3 mg/kg (Esk0.3, n = 60) or 0.5 mg/kg esketamine (Esk0.5, n = 60). The Esk0.5 group required significantly less propofol (126.1 ± 38.5 mg vs. 154.5 ± 25.8 mg, P < 0.001) and shorter induction time (51.5 ± 8.3 s vs. 58.6 ± 9.1 s, P < 0.001) compared to Esk0.3. However, postoperative recovery time (17.6 ± 4.8 min vs. 13.2 ± 5.8 min, <I>P</I> < 0.001) and operating room exit time (28.7 ± 7.6 min vs. 21.5 ± 4.1 min, <I>P</I> < 0.001) were prolonged in the Esk0.5 group. No differences were observed in procedure duration or patient satisfaction. The Esk0.5 group exhibited higher heart rates at gastroscope withdrawal (83.55 ± 5.34 vs. 80.46 ± 7.45 bpm, P = 0.01), alongside increased adverse events including secretions (13.3% vs. 3.3%, P = 0.037) and diplopia (13.3% vs. 3.3%, P = 0.037). Both groups showed high rates of involuntary twitching (28.3% vs. 35.0%). Esketamine 0.5 mg/kg reduces propofol requirements and accelerates induction but prolongs recovery and increases specific adverse events, necessitating individualized dosing and postoperative monitoring to optimize safety.