Effects of S-ketamine on Postoperative Recovery Quality and Inflammatory Response in Patients Undergoing Modified Radical Mastectomy

Introduction S-ketamine plays an important role in reducing postoperative pain, but its impact on the quality of recovery in breast cancer has not been clarified. We designed this trial to explore the effects of s-ketamine on the quality of postoperative recovery and inflammatory response in modified radical mastectomy. Methods A total of 138 patients were randomly assigned to group C (group control), group K1 (group of s-ketamine dose 1) and group K2 (group of s-ketamine dose 2). Groups K1 and K2 were given 0.1 mg/kg, 0.2 mg/kg s-ketamine intravenous (IV) after induction, followed by 0.1 mg/kg/h or 0.2 mg/kg/h continuous intravenous infusion, respectively. Group C received the same volume of saline. A 40-item Quality of Recovery Questionnaire (QoR-40) was used to assess the quality of recovery at 24 h postoperatively. Changes in inflammatory markers, nociceptive thresholds, and the occurrence of adverse events were recorded at 24 h postoperatively. Results The QoR-40 scores at 24 h postoperatively were higher in group K2 [182.00 (179.00–185.00)] compared to group K1 [174.00 (169.50–180.50)] and group C [169.00 (163.75–174.25)] (group K2 vs. group K1, P < 0.001; group K2 vs. group C, P < 0.001). At 24 h postoperatively, the neutrophil count, NLR (neutrophil–lymphocyte ratio), and CRP (C-creative protein) were all significantly lower in group K2 than group C( P < 0.05), no differences were observed between group K1 and C( P > 0.05), group K1 and K2( P > 0.05), respectively. There was no significant difference in the incidence of adverse effects among the three groups ( P > 0.05). Conclusions A high dose of s-ketamine improved the quality of recovery at 24 h after surgery, as well as alleviated the inflammatory response without increasing the incidence of adverse effects.