Efficacy of Cerebral Oxygen Saturation Monitoring for Perioperative Neurocognitive Disorder in Adult Noncardiac Surgical Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Perioperative neurocognitive disorders (PND) are common perioperative complications associated with various poor outcomes. Regional cerebral oxygen saturation (rSO2) monitoring is a non-invasive technique based on near-infrared spectroscopy detection. Due to the considerable controversy among currently published studies on the application of intraoperative rSO2 monitoring in adult patients undergoing elective non-cardiac surgery, this study aims to conduct a systematic review and meta-analysis to provide more comprehensive and robust evidence to support clinical decision-making. This study conducted a systematic literature search of databases including PubMed, Embase, CENTRAL, and Web of Science, from their inception to May 1, 2024. The eligible randomized controlled trials included adult patients undergoing elective non-cardiac surgery under general anesthesia who received optimized anesthesia management guided by rSO2 monitoring and those in the control group who received routine anesthesia management under standard monitoring or blinded rSO2 monitoring. The primary outcomes were the incidence of PND, including postoperative delirium (POD) and postoperative cognitive dysfunction (POCD), and Mini-Mental State Examination (MMSE) scores. Secondary outcomes included the incidence of intraoperative cerebral desaturation and length of hospital stay (LOS). The pooled results showed that compared to the control group, optimized anesthesia management guided by intraoperative rSO2 monitoring significantly reduced the incidence of POCD within 7 days postoperatively and may reduce the incidence of POCD at 3 months and longer periods postoperatively. However, it may not reduce the incidence of POD within 7 days or longer periods postoperatively, improve MMSE scores, reduce the incidence of intraoperative cerebral desaturation, or shorten LOS. Given the substantial heterogeneity in the pooled results for MMSE scores within 7 days postoperatively and LOS, and the limited number of studies reporting the incidence of POD, POCD, and MMSE scores after 7 days postoperatively, the related results should be interpreted with caution. Despite the presence of heterogeneity and the inclusion of a limited number of studies for some outcomes, it is still recommended that clinical anesthesiologists routinely perform intraoperative rSO2 monitoring and optimize intraoperative anesthesia management based on the monitoring results to maximize rSO2 and improve cerebral perfusion, thereby improving patients' neurocognitive outcomes. Further large-scale high-quality studies are needed to confirm the conclusions of this study.