Esketamine on Postoperative Sleep Disturbance of Patients Undergoing Spinal Surgery

The goal of this clinical trial is to learn about the effect of intraoperative esketamine infusion on postoperative sleep disturbance(PSD) of patients undergoing spinal surgery. The main aims to answer are:

* To explore the effect of intraoperative infusion of esketamine on the incidence of postoperative sleep disturbance and sleep quality in patients undergoing spinal surgery. * To explore the effect of intraoperative infusion of esketamine on postoperative pain, anxiety and depression ; Participants will be patients undergoing spinal surgery with general anesthesia at Beijing Tiantan Hospital. 0.3mg/kg/h esketamine or saline will be infused during surgery . The incidence of sleep disturbance , sleep quality, pain scores, hospital anxiety and depression scores and perioperative adverse events after surgery will be investigated.