Effects Of Esketamine On Pain,Mood And Serum BDNF After Thoracoscopic Surgery

OBJECTIVE:Pain after thoracic surgery is often unbearable,and increased postoperative depressed mood in patients is significantly associated with post-operative dyspnea and pain.Esketamine is about twice as potent as racemic ketamine for pain relief,and small doses of esketamine can also have positive effects on mood.The purpose of this study was to investigate the effect of intraoperative esketamine on postoperative pain and mood,serum BDNF in patients undergoing elective thoracoscopic surgery.Materials and methods:This is a randomized,double-blind,controlled study.A total of 67patients(ASA I-III)undergoing elective thoracic surgery were randomly assigned to esketamine group(group K)or saline group(group C).Patients in group K were given esketamine 0.5 mg/kg(0.1 ml/kg)after intubation,and then continued infusion of esketamine 0.2 mg/kg·h(0.2ml/kg·h)until the pleura closed.Patients in group C used the same volume of normal saline during anesthesia.Visual analog scale pain scores at rest and cough(VASrest,VAScoughing scores),and the short-form Mc Gill’s Pain Questionnaire(SF-MPQ score)were collected at 4 h,24 h,48h and 7 days postoperatively.Montgomery Depression Rating Scale(MADRS)scores were collected before surgery,1,2,and 7days after surgery,and 2ml of blood was drawn before surgery,immediately after surgery,and 1 day after surgery to detect serum brain-derived neurotrophic factor.Research results:Both groups were similar with respect to patient characteristics(P>0.05);the VASrest score at rest at 4 and 24 hours after operation in the esketamine group was significantly lower than that in the normal saline group(P=0.003),and at 4 hours after operation The number of patients with moderate-to-severe pain(VAScoughing≥4)caused by cough in the esketamine group was significantly less than that in the normal saline group(P=0.011).The Affective scores of the short-form Mc Gill’s Pain Questionnaire in the esketamine group were significantly lower than those in the normal saline group at 24 and 48 hours after surgery(P=0.023,P=0.017).However,there was no significant difference in the scores of the Montgomery Rating Scale for Depression between the two groups(group-by-time interaction P =0.005,effects for time at each level of group P>0.05).There was no significant difference in the level of BDNF between the two groups before surgery(P>0.05),and the level of BDNF in the esketamine group gradually increased with time(time effect P < 0.001),were higher than those in the normal saline group immediately after surgery and 1 day after surgery(P=0.033,P=0.009).There were no differences between the two groups in postoperative remedy analgesic drugs use,hospital stay,and drug-related adverse events(P>0.05).Conclusion:Esketamine can reduce the pain intensity within 24 hours after thoracoscopic surgery,especially improve the pain-related adverse emotions 1-2 days after surgery.However,further studies are needed to explore the lasting effects of esketamine on emotional responses to postoperative pain and the underlying mechanisms.