Effect of Opioid-free Anesthesia on Sleep Quality, Cognitive Function and Recovery Quality After General Anesthesia in Elderly Patients

Exclusion Criteria

• •Chronic pain;
• •* severe liver dysfunction (total bilirubin 2 mg dl-1);
• •* severe renal dysfunction (glomerular filtration rate 60ml min-1 1.73m-2);
• •* preoperative heart rate \<50 beats / min, sick sinus syndrome, severe heart block;
• •* dementia or significant neurological disease (such as stroke, epilepsy, intracranial tumor, Parkinson disease, etc);
• •* history of alcohol or drug abuse;
• •* preoperative or PSQI score 7 or sleep disturbance;
• •* Cannot cooperate with the scale survey
• •* Allergic to the trial drug