Abstract
BACKGROUND: Immunosuppression and inflammation are associated with postoperative rehabilitation and tumor prognosis. This study aimed to explore the effects of s-ketamine combined with sevoflurane anesthesia on postoperative cellular immune function and inflammatory responses in patients undergoing radical esophagectomy. METHODS: Fifty adult patients scheduled for radical esophagectomy were randomly divided into a control group receiving routine anesthesia (C) and an experimental group receiving s-ketamine combined with sevoflurane anesthesia (E). All patients were maintained under general anesthesia with sevoflurane and remifentanil and received patient-controlled intravenous analgesia postoperatively. In addition, the patients of group E received continuous intravenous infusion of 0.2 mg·kg-1·h-1 s-ketamine intraoperatively and 1 mg/kg s-ketamine in the patient-controlled intravenous analgesia for postoperative analgesia. Blood samples for lymphocyte subsets and inflammatory cytokines were collected preoperatively and on postoperative days (POD) 3 and 7. The primary outcome was the percentage of CD3+ lymphocytes on POD 7. Secondary outcomes included the percentages of other lymphocyte subsets (CD4+, CD8+, natural killer, and B cells); levels of inflammatory cytokines: C-reactive protein, serum amyloid A, interleukin-6, interleukin-10, and tumor necrosis factor-alpha-α; remedial analgesic consumption within 48 hours; incidence of postoperative adverse events; unplanned intensive care unit transfers; and postoperative length of stay. RESULTS: A total of 48 patients completed this analysis. The percentage of CD3+ lymphocytes changed significantly over time (P < .001), but no significant differences were found between the groups or in group × time interactions. Both groups showed significantly elevated C-reactive protein and serum amyloid A levels on POD 3 and 7 compared to baseline (P < .05). Group E had a significantly shorter postoperative length of stay compared to group C (P < .05). No significant differences were found between the groups regarding remedial analgesic consumption within 48 hours, incidence of postoperative adverse events, and unplanned intensive care unit transfers. CONCLUSION: S-ketamine combined with sevoflurane anesthesia did not significantly affect postoperative cellular immune function in patients undergoing radical esophageal cancer surgery.