Nasal High-flow Oxygen Therapy During Rehabilitive Exercise Training in ILD

Although uncommon, interstitial lung diseases (ILDs), and particularly idiopathic pulmonary fibrosis (IPF), are progressive, irreversible, and ultimately fatal without treatment. Pharmacological therapies can slow the decline in forced vital capacity (FVC) and six-minute walk distance (6MWD), but they do not improve exercise-related respiratory limitations or quality of life. Therefore, pulmonary rehabilitation (PR) is recommended for patients with a confirmed diagnosis of ILD/IPF who experience exercise limitation and significant functional impairment. However, the benefits of PR remain modest, and the optimal rehabilitation strategies for these patients have yet to be defined, particularly given the severe dyspnea and often profound exertional hypoxemia that characterize the disease. To optimize the effects of PR, especially exercise training, the use of high-flow nasal oxygen (HFNO) during exercise has been proposed in certain respiratory conditions such as chronic obstructive pulmonary disease (COPD). By improving oxygenation and exercise tolerance, HFNO applied during exercise training sessions may enhance the effectiveness of pulmonary rehabilitation.

Inclusion Criteria: * Age ≥18 years. * Confirmed diagnosis of interstitial lung disease (ILD). * Indication for pulmonary rehabilitation according to current guidelines, defined as exercise limitation associated with significant functional impairment. * Clinically stable disease with no recent exacerbation requiring treatment modification within the previous 3 months. * Affiliation with a health insurance/social security system. * Ability to understand the study procedures and provide written informed consent. Non-inclusion Criteria: * Inability to perform cycle ergometer exercise testing. * Participation in a pulmonary rehabilitation program within the previous 6 months. * Any contraindication to exercise testing according to standard clinical practice. * Inability to provide informed consent. * Current participation in another interventional study during an exclusion period. * Pregnant or breastfeeding women. * Individuals deprived of liberty by judicial or administrative decision. * Adults under legal protection or guardianship.