The Effect of Low-Dose Dexmedetomidine on Perioperative Neurocognitive Dysfunction in Elderly Patients Undergoing Endoscopic Retrograde Cholangiopancreatography (ERCP): A Randomized, Controlled, Double-Blind Trial

Objective: This study investigates the effect of low-dose dexmedetomidine infusion on perioperative neurocognitive function in elderly patients undergoing endoscopic retrograde cholangiopancreatography (ERCP). Patients and Methods: This double-blind trial enrolled 80 elderly ERCP patients randomized to receive dexmedetomidine (Group D) or placebo (Group S). Group D received dexmedetomidine at 0.4 mu gkg(- 1)h(- 1) starting 15 minutes before surgery until completion, along with propofol at 1.5 mg/kg for anesthesia. Group S received saline and propofol in a similar manner. Anesthesia was maintained with dexmedetomidine at 0.4 mu gkg(- 1)h(- 1) and propofol at 1- 2 mg/kg during surgery. Cognitive function was assessed using the Mini-Mental State Examination (MMSE) preoperatively and on postoperative days 1, 3, and 5. Primary outcome was perioperative neurocognitive disorder (PND) incidence on day 5; secondary outcomes included changes in perioperative IL-6, cortisol, S100-beta, hemodynamics, anesthesia parameters, postoperative pain, agitation scores, and adverse events. Results: All 80 patients completed the trial. On postoperative day 5, the cumulative probability of PND incidence was significantly lower in Group D than in Group S (12.5% vs 35%, P=0.018). Group D also had lower levels of IL-6 (F=199.472, P< 0.001), S100-beta (F=2681.964, P< 0.001), and cortisol (F=137.637, P< 0.001). Propofol doses were lower in Group D (706.1 +/- 202.4 vs 1003.3 +/- 203.7, P< 0.001), and bradycardia rates were higher (45% vs 15%, P=0.003), though atropine use did not significantly differ between groups. Group D showed greater stability in mean arterial pressure. Postoperative complications and adverse reactions were similar across groups. Conclusion: Perioperative low-dose dexmedetomidine infusion with propofol in elderly ERCP patients ensures safe and effective monitored anesthesia care (MAC), reducing PND incidence by mitigating peripheral inflammation and stress responses. Long-term follow-up is needed to fully evaluate PND incidence.