Noninvasive respiratory therapy: A physiology-oriented approach across acute, chronic, home, and palliative care settings.

Noninvasive respiratory therapy has evolved from a strategy used to avoid endotracheal intubation in selected forms of acute respiratory failure into a broader framework encompassing acute care, chronic respiratory failure, sleep-disordered breathing, home respiratory support, pulmonary rehabilitation, and palliative care. The term now encompasses conventional oxygen therapy, high-flow nasal cannula therapy, continuous positive airway pressure, bilevel noninvasive ventilation, home noninvasive ventilation, home high-flow therapy, and positive airway pressure therapy for sleep-related breathing disorders. This review proposes a physiology-oriented approach. Rather than selecting a device solely according to the disease, clinicians should identify the dominant physiological problem: impaired oxygenation, alveolar hypoventilation, upper-airway obstruction, increased work of breathing, respiratory muscle fatigue, impaired secretion clearance, or the need for comfort-oriented support. In acute care, noninvasive ventilation is well established for acute hypercapnic respiratory failure due to COPD exacerbations and for acute cardiogenic pulmonary edema, whereas high-flow nasal cannula therapy, continuous positive airway pressure, and noninvasive ventilation require more careful selection in patients with acute hypoxemic respiratory failure. In chronic care, home noninvasive ventilation and home high-flow therapy should be understood as components of long-term respiratory care systems rather than as simple device prescriptions. Practical success depends on appropriate interface selection, leak control, humidification, patient-device synchrony, airway clearance, patient education, and safe monitoring. A physiology-oriented and patient-centered framework may improve the appropriate use of noninvasive respiratory therapy across the continuum of care.