A Single Preoperative Dose of S-Ketamine Has No Beneficial Effect on Chronic Postsurgical Pain in Patients Undergoing Video-Assisted Thoracoscopic Surgical Lung Lesion Resection: A Prospective Randomized Controlled Study

To evaluate the efficacy of a single preoperative dose of S-ketamine for chronic postsurgical pain (CPSP) in patients undergoing video-assisted thoracoscopic surgical lung lesion resection (VATS).A prospective randomized, double-blind controlled study.Patients were enrolled from March 17, 2021, to November 18, 2021, at a single tertiary academic hospital.Patients were 18-to-65 years of age and undergoing VATS.The experiment was divided into an S-ketamine group (0.5 mg/kg intravenous injection before anesthesia induction) or a placebo group (the same volume of normal saline).The primary endpoint was the incidence of CPSP and its neuropathic component. The secondary endpoints included acute postoperative pain, the use of postoperative analgesics, anxiety and sleep quality scores, and the occurrence of adverse effects. There were no significant differences between the 2 groups in the incidences of CPSP, neuropathic pain, acute postoperative pain, and postoperative use of analgesics. The sleep quality scores on the first postoperative day differed significantly between the groups (47.45 ± 27.58 v . 52.97 ± 27.57, p = 0.049), but not the anxiety scores. In addition, adverse effects were similar between the 2 groups.A single preoperative dose of S-ketamine in patients who underwent VATS had no significant effect on acute and chronic postoperative pain or the consumption of analgesics after surgery. A single preoperative dose of S-ketamine could improve sleep on the first day after surgery, whereas it had no significant effect on anxiety levels.