Meta-Analysis of the Correlation between Postoperative Cognitive Dysfunction and Intraoperative Cerebral Oxygen Saturation

Objective. This study is aimed at performing a meta-analysis for discussing the association between postoperative cognitive dysfunction (POCD) and cerebral cortical oxygen saturation after surgery (rSO2). Method. Search common English databases such as Cochrane Library, PubMed, and Embase databases to evaluate the quality of all references. According to the normalized mean difference (SMD) and 95% confidence interval calculated by the revman5 software, the correlation between reported POCD and rSO2 was evaluated. The retrieval time is up to February 1, 2021. Results. A total of 7 randomized controlled trials and 564 POCD patients were included in the study, with follow-up duration of 1-12 months. All patients were divided into control and operation subgroups. In the subgroup analysis of elderly patients, abdominal surgery, and orthopedic surgery, the mean intraoperative cerebral oxygen saturation of patients with POCD was significantly lower than those of patients without POCD ( $I^2=55\%$ , $\text{SMD}=-0.57$ ). Conclusion. Lower intraoperativersO2 was associated with reduced incidence of neurological complications and renal alure as well as the length of stay in the intensive care unit and the total hospital stay.