Study of Postoperative Cognitive Decline in Aged Patients

postoperative cognitive decline is a common and deleterious complication in aged patients.The link between inflammation and postoperative cognitive decline has also been reported.However,the link between SOD1，SOD2，Osteopontin， Kallikrein-6，and Contactin-1 and postoperative cognitive decline is unknown. In this project ,investigators examine the relationship between 5 cytokines measured at there timepoints (preoperative \[PREOP\], postoperative day 1 \[POD1\] , and postoperative day 3\[POD2\]) and postoperative cognitive decline among older adults undergoing orthopedic surgery.