Respiratory failure is a common and serious condition in clinical settings, often categorized as an acute and critical illness. Simply put, respiratory failure occurs when respiratory function is extremely poor. It is caused by severe impairment of pulmonary ventilation and gas exchange due to various reasons. Even at rest, sufficient gas exchange cannot be maintained, leading to serious hypoxemia or concurrent hypercapnia. Clinically, this often presents with severe breathing difficulties, hypoxia, cyanosis, and requires immediate intervention to prevent potentially life-threatening complications.