High-Flow Nasal Cannula After Extubation in Acute Brain Injury

Inclusion Criteria: * Patients aged 16 years or older. * Admission to the Surgical Intensive Care Unit after neurosurgery for acute brain injury, including traumatic brain injury, intracerebral hemorrhage, subarachnoid hemorrhage, ischemic stroke, or other acute neurosurgical brain conditions. * Requirement for invasive mechanical ventilation for at least 24 hours. * Undergoing planned extubation after clinical assessment by the treating ICU team. * Successful completion of a spontaneous breathing trial lasting 30 to 120 minutes. * Adequate airway protection, defined as an Airway Care Score less than 8 points. * Neurological readiness for extubation, as assessed by Glasgow Coma Scale score and bedside neurological examination. * Adequate oxygenation before extubation, including PaO2/FiO2 greater than 200 mmHg and PEEP less than 7 cmH2O. Exclusion Criteria: * Pre-existing tracheostomy. * Known upper airway obstruction, including airway stenosis or airway tumor. * Suspected cerebrospinal fluid leak or complex skull base fracture. * Unplanned self-extubation. * Requirement for immediate prophylactic reintubation before initiation of post-extubation oxygen therapy. * Requirement for non-invasive ventilation before initiation of the study exposure. * Missing key clinical data required for outcome assessment or propensity score matching.