Non-invasive mechanical ventilation as an adjunct to pulmonary rehabilitation in patients with bronchiectasis: a pathophysiological perspective.

Bronchiectasis is a complex respiratory disease characterized by irreversible bronchial dilatation, mucus hypersecretion, and impaired mucociliary clearance. These structural changes result in a predominantly obstructive pattern that increases airway resistance, impairs gas exchange, and leads to air trapping and dynamic hyperinflation. This scenario increases the work of breathing (WOB) and places the inspiratory muscles at a mechanical disadvantage, precipitating muscle fatigue during exercise and limiting the potential benefits of pulmonary rehabilitation (PR). In this context, non-invasive mechanical ventilation (NIV) emerges as an intervention with high biological plausibility as an adjunct during physical training. Its mechanism of action is based on the application of inspiratory positive pressure to overcome resistive load and expiratory pressure to counteract hyperinflation, thereby optimizing ventilatory efficiency. Although the efficacy of NIV in improving exercise tolerance is well documented in chronic obstructive pulmonary disease (COPD), in bronchiectasis the evidence is still incipient and largely based on extrapolation; therefore, it is imperative to conduct research to define its efficacy and safety in order to improve functional prognosis in this population.