Impact of xenon on postoperative outcomes in cardiac surgery: A systematic review and meta-analysis of delirium incidence and associated clinical parameters

Background: Postoperative delirium (POD) is a common complication after cardiac surgery, leading to increased morbidity and hospital stays. The anesthetic choice may affect POD incidence and related complications. Xenon has emerged as a promising alternative for its cardio- and neuroprotective effects; however, its effectiveness in preventing POD following cardiac surgery remains unclear. Objective: To evaluate the effectiveness of Xenon in preventing postoperative delirium in patients undergoing cardiac surgery. Methods: Articles were searched using databases including PubMed, Medline, Scopus, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL) from the databases' inception until August 18, 2023. A total of five randomized controlled trials were included in this systematic review and meta-analysis. Six outcomes were extracted and assessed: postoperative delirium incidence, respiratory disorder, duration of mechanical ventilation, length of hospital stay, ICU stay length, and mortality. Results: There were no significant differences between the Xenon and Control groups across six assessed outcomes: postoperative delirium incidence (p = 0.46), respiratory disorder (p = 0.66), duration of mechanical ventilation (p = 0.80), length of hospital stay (p = 0.93), ICU stay length (p = 0.32), and mortality (p = 0.43). Pooled effect sizes ranged from non-significant to moderately heterogeneous, with overall effects constantly failing to reach statistical significance. Conclusions: These results suggest that Xenon does not display clinically meaningful benefits over control groups for the assessed outcomes.