HFNO Versus Face Mask for Cerebral Oxygenation During Procedural Sedation

Inclusion Criteria: * Age 18 years or older * American Society of Anesthesiologists physical status I-IV * Scheduled for an elective diagnostic or interventional procedure performed under procedural sedation in a non-operating-room setting * Ability to provide written informed consent * Willingness to participate in the study Exclusion Criteria: * Age younger than 18 years * Refusal or inability to provide written informed consent * Known neurological disorders * History of ischemic or hemorrhagic stroke * History of traumatic brain injury or previous cranial surgery * Peripheral arterial disease or systemic vasculitis * Advanced heart failure * Uncontrolled hypertension * Uncontrolled diabetes mellitus * Advanced chronic obstructive pulmonary disease (COPD) * Severe anemia (hemoglobin \<8 g/dL) * Skin lesions or other conditions preventing proper placement of NIRS sensors * Nasal deformity or nasal obstruction preventing the use of high-flow nasal oxygen therapy * Any condition that, in the opinion of the investigators, could interfere with study participation or the interpretation of study results