The effect of dexmedetomidine on perioperative electroencephalogram characteristics and postoperative sleep disturbance in patients undergoing laparoscopic gynecological surgery: a randomized controlled trial

INTERVENTION: Dexmedetomidine Group:Intravenous infusion of dexmedetomidine at 0.5 µg/kg 10 minutes before anesthesia induction; during the maintenance phase of anesthesia, intravenous infusion of dexmedetomidine at 0.3 µg/kg/h (discontinued 30 minutes before the end of surgery).;Normal saline Group:Intravenous infusion of normal saline at an equivalent volume to the dexmedetomidine group 10 minutes before anesthesia induction; during the maintenance phase of anesthesia, intravenous infusion of normal saline at an equivalent volume to the dexmedetomidine group (discontinued 30 minutes before the end of surgery).; CONDITION: Postoperative sleep disorder PRIMARY OUTCOME: Incidence of postoperative sleep disturbance; SECONDARY OUTCOME: Changes in patients' peri?operative electroencephalogram;Visual Analogue Scale Score;Postoperative opioid use; INCLUSION CRITERIA: 1. ASA physical status I‐III; 2.Aged 18 to 65 years; 3.Undergoing elective urological laparoscopic surgery; 4.Fully understand the trial procedures and voluntarily participate, with signed informed consent.