Objective:To evaluate the effect of general anesthesia combined with epidural block on postoperative sleep in the frail elderly patients undergoing gastrointestinal tumor surgery.Methods:Ninety frail patients of either sex, aged 65-80 yr, with body mass index of 18-30 kg/m 2, of American Society of Anesthesiology physical status Ⅱ-Ⅲ, scheduled for elective open gastrointestinal tumor surgery (FRAIL score >2), were divided into 2 groups ( n=45 each) using a random number table method: general anesthesia group (GA group) and general anesthesia combined with epidural block group (GE group). Combined intravenous-inhalational anesthesia was carried out in group GA.Epidural block was performed before induction of anesthesia, and the method of general anesthesia was the same as that described in group GA, and the consumption of propofol and remifentanil was adjusted according to the BIS value, sweat and tears, heart rate and blood pressure during operation in group GE.Postoperative intravenous analgesia was performed to maintain VAS score ≤3.Wearable devices were used to monitor sleep parameters at 1 day before surgery and 1, 3 and 7 days after surgery.Sleep quality was assessed using Pittsburgh Sleep Quality Index and Quality of Recovery-15 questionnaire at 1 day before surgery and 1, 3, 7 and 30 days after surgery.The intraoperative consumption of propofol, sufentanil and remifentanil were recorded.The requirement for postoperative rescue analgesia and total pressing times of patient-controlled analgesia (PCA) within 48 h after surgery were recorded.Serum C-reactive protein concentrations were determined by immunoturbidimetry at 1 day before surgery and 1 day after surgery, and the adverse reactions at 7 days after surgery were recorded. Results:Compared with group GA, the consumption of remifentanil was significantly reduced, the total sleep score, deep sleep ratio, rapid eye movement ratio and Quality of Recovery-15 score were increased, the Pittsburgh Sleep Quality Index was decreased, and the incidence of postoperative nausea and vomiting was decreased on 1st and 3rd days after operation ( P<0.05), and no significant change was found in the serum C-reactive protein concentration and postoperative requirement for rescue analgesia, and total pressing times of PCA in group GE ( P>0.05). Conclusions:General anesthesia combined with epidural block can improve short-term sleep quality and recovery quality after gastrointestinal tumor surgery in elderly frail patients.