HFNC vs. NIV in Acute COPD Exacerbations

Inclusion Criteria: \- patients age ≥18 years with a confirmed diagnosis of COPD who presented to the ED with exacerbations that did not respond to bronchodilator therapy Exclusion Criteria: * patients aged younger than 18 years * patients had an arterial pH ≤ 7.25; * patients were in cardiopulmonary arrest; * patients had unstable cardiac arrhythmias or hemodynamic instability; * patients showed persistent hypoxemia despite supplemental oxygen therapy; * patients were unconscious or uncooperative; * patients could not protect their airway or manage secretions; * patients had cardiogenic pulmonary edema, active hemoptysis, pneumothorax, recent upper respiratory tract/esophagus surgery, significant airway obstruction (e.g., laryngeal mass or tracheal tumor), active upper gastrointestinal bleeding, or facial trauma or deformities