Lung Protective Effects of Esketamine in Patients undergoing video-assisted thoracoscopic surgery：A randomized controlled trial

Abstract Background Video-assisted thoracic surgery (VATS) is associated with pulmonary function impairment on account of the specificity of the surgical site.Recent studies have reported that the widespread application of esketamine in general anesthesia.Esketamine acts on multiple receptors but the role in pulmonary protection is indeterminate.Hence,we hypothesized that esketamine exerts protective effects on pulmonary function in patients undergoing VATS and further investigate the possible mechanisms and determine the effects of different dosages. Methods Patients with aged 18–65 years scheduled for VATS were included in this study.The patients were assigned randomly to 3 groups as follows:esketamine was administered in group K1 as an initial loading bolus of 0.5 mg/kg before induction and followed by a maintenance infusion of 0.5 mg/kg/h during surgery,patients in group K2 received esketamine as an initial loading bolus of 1.0 mg/kg before induction and followed by 0.5 mg/kg/h during surgery.And group C was received identical amount of normal saline as a placebo. Results In total,85 eligible patients were enrolled in our study.Patients in the placebo group had lower a/A ratio and OI,higher RI and A-aDO2 when discharged from ICU and 24h postoperatively (all p༜0.05),higher incidence of postoperative pulmonary complications (PPCs)(p = 0.017),higher resting and movement numerical rating scale (NRS) at 24h and 48h postoperatively,greater fluctuations of blood pressure and heart rate intraoperatively compared with the esketamine groups.while the time of tracheal extubation,length of intensive care unit stay,the serum levels of procalcitonin (PCT) and the incidence of postoperative adverse events were similar among the 3 groups. Conclusions Esketamine administration was effective in protecting pulmonary function in patients undergoing VATS by improving oxygenation,reducing hemodynamic fluctuation and postoperative pain.But the relationship between the optimal dosage and minimal adverse events needed further researches.