Clinical Research Directory

Inclusion Criteria: * Elderly patients aged 65 and above. * Patients undergoing non-cardiac major surgery in thoracic surgery, lung cancer surgery, multi-level spinal surgery in neurosurgery and orthopedics, or liver cancer surgery in hepatobiliary and pancreatic surgery, under general anesthesia with an expected surgery duration of 2 hours or more. * Patients scheduled for arterial catheterization. * Patients who are able to take oral intake from postoperative day #1. Exclusion Criteria: * Patients with uncontrolled systemic conditions such as diabetes, hypertension, renal disease, liver disease, and other systemic illnesses. * Those with visual impairment. * Patients with cognitive impairment based on the Mini-Mental State Examination for Dementia Screening criteria. * Individuals experiencing difficulty in communication. * Those diagnosed with neurological disorders (such as brain hemorrhage, stroke, brain tumor, dementia, Parkinson's disease, cognitive impairment, depression, etc.). * Patients diagnosed with alcohol or substance addiction. * Patients with cancelled scheduled surgeries. * Patients undergoing minor surgeries with expected anesthesia durations of less than 2 hours.