Effect of Different Doses of Dexmedetomidine on Cerebral Oxygen Saturation and Postoperative Anxiety in Elderly Patients

To investigate the effect of different doses of dexmedetomidine on Cerebral Oxygen Saturation and Postoperative anxiety in elderly patients undergoing laparoscopic surgery

Inclusion Criteria:Patients aged 65 years or older who underwent elective laparoscopic surgery under general anesthesiaBMI less than 30 kg/m2American Society of Anesthesiologists (ASA) grades I-IIIThe score of Mini Mental state examination≥24Exclusion Criteria:Patients with heart, lung and other vital organ disordersThe score of Mini Mental state examination≤23Preoperative psychiatric disorders or long-term use of drugs affecting the psychiatric systemHave severe visual, hearing, speech impairment or other inability to communicate with the visitorRefuse to sign informed consentknown preoperative left ventricular ejection fraction less than 30%, sick sinus syndrome, severe sinus bradycardia (<50 beats per min [bpm]), or second-degree or greater atrioventricular block without pacemaker