Cognitive function will be evaluated within 3 days before operation and 3 days, 14 days and 3 months after operation. Delirium and VAS pain score will be evaluated 24 hours after operation. Venous blood will be taken before operation and 24 hours after operation to detect cognitive related markers and inflammatory factors. In addition, 10 blood samples of patients in each group were selected for RNA omics test. One month, six months and 12 months after operation, cognitive function was evaluated by cognitive function telephone questionnaire (TICS-M), and the ability of daily living was evaluated by IDAL. In addition, 20 non-surgical patients were selected for cognitive function evaluation at the same time point as the exercise effect of POCD detection.
To observe whether adjusting the level of intraoperative controlled hypotension through cerebral oxygen saturation monitoring can improve postoperative cognitive function(POCD) and reduce postoperative neurological complications, a prospective randomized controlled study method will be used in this study. 400 elderly patients undergoing shoulder arthroscopic surgery under general anesthesia combined with brachial plexus block will be selected. They will be randomly divided into control group and experimental group according to whether cerebral oxygen saturation monitoring was used during the operation. The control group maintain the target blood pressure only according to the controlled hypotension guideline, and the experimental group adjust the controlled hypotension level under the guidance of cerebral oxygen saturation monitoring. The general condition, operation, anesthesia and hospitalization related data of the patients will be recorded.