Cerebral Oxygen Consumption Response to Increased Oxygen Supply and Postoperative Delirium in Older Surgical Patients

Exclusion Criteria

• •Diagnosis of dementia or presence of delirium before surgery
• •Loss of capacity to provide informed consent
• •Moderate or severe cerebrovascular stenosis diagnosed before surgery
• •Moderate or severe obstructive or restrictive pulmonary dysfunction identified on preoperative pulmonary function testing
• •Requirement for supplemental oxygen therapy before surgery
• •History of neurological disorders (e.g., Parkinson's disease, stroke) or prior brain surgery
• •Severe hepatic dysfunction (AST or ALT \> 120 IU/L)
• •Severe renal dysfunction (estimated GFR \< 15 mL/min/1.73 m²)
• •Persistent severe hemodynamic instability (mean arterial pressure \< 60 mmHg)
• •Skin conditions preventing placement of the forehead fNIRS sensor
• •Combined surgical procedures performed concurrently
• •Planned postoperative admission to the intensive care unit