The Effect of Opioid-Free Anesthesia with Esketamine on Postoperative Cognitive Dysfunction in Elderly Patients Undergoing Thoracoscopic Surgery: A Prospective, Randomized, Controlled Trial.

[BACKGROUND] Postoperative cognitive dysfunction (POCD) occurs at a higher rate in elderly patients undergoing thoracoscopic surgery, significantly affecting postoperative recovery and quality of life. However, effective interventions and anesthesia-related risk factors remain poorly understood.

[PURPOSE] This study aimed to evaluate the impact of esketamine-based opioid-free anesthesia (OFA) on POCD in elderly patients undergoing thoracoscopic lung cancer surgery.

[PATIENTS AND METHODS] In this study, 80 elderly patients undergoing thoracoscopic lung cancer surgery were randomly allocated to receive either opioid-free anesthesia with esketamine (OFA group) or opioid-based anesthesia (Control group). The primary outcome was the incidence of POCD within 3 days. Logistic regression was used to identify risk factors for POCD.

[RESULTS] The incidence of POCD was 20% and 42.5%, respectively, in the OFA group and the Control group (risk ratio [RR], 0.47; 95% confidence interval [CI], 0.24 to 0.92; risk difference [RD], -22.5%; 95% CI, -44.8% to -0.2%; p = 0.054). Compared to the Control group, patients in the OFA group had lower simple reaction time at 1 and 3 days post-surgery (1-day: p = 0.031; 3-day: p = 0.020). In addition, patients in the OFA group demonstrated higher mean values for mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), cardiac index (CI), stroke volume (SV), and systemic vascular resistance index (SVRI), as well as smaller variation ranges for these parameters, compared to the Control group (all p < 0.05), Furthermore, age (OR, 2.738; 95% CI, 1.37 to 6.30; p = 0.008), CO range (OR, 4.673; 95% CI, 2.25 to 11.82; p < 0.001), and time to first analgesic request (OR, 0.399; 95% CI, 0.18 to 0.76; p = 0.01) were validated to correlate with POCD.

[CONCLUSION] Esketamine-based OFA did not significantly reduce POCD incidence, and it was associated with improved postoperative reaction time and reduced intraoperative hemodynamic fluctuations.