nasal high flow to maintain the benefits of pulmonary rehabilitation in chronic obstructive pulmonary disease patients

Conditions: Chronic Obstructive Pulmonary Disease

Summary: chronic obstructive pulmonary disease (copd) is a major cause of disability and mortality worldwide. this systemic disease progressively leads to dyspnea and exercise capacity impairment. pulmonary rehabilitation effectively improves exercise capacity, dyspnea and quality of life in patients with copd. however, its benefits progressively fade over time due to several factors such as the lack of regular exercise activity, dyspnea, airway secretions, hematosis impairment and acute exacerbations which can lead to hospitalization and accelerated muscle wasting. nasal high flow (nhf) is a support used to deliver heated and humidified high flow air (up to 60 l/min) through nasal canula providing promising physiological benefits such as positive airway pressure or upper airway carbon dioxide washout. it can be used in association with oxygen and offers the advantage to overtake the patient's inspiratory flow, providing a stable inspired fraction of oxygen. nasal high flow has widely been studied in pediatric and adult intensive care units and seems better than conventional oxygen therapy and as effective as noninvasive ventilation with regards to mortality to treat hypoxemic acute respiratory failure. more recently, several studies have shown that long-term nasal high flow could contribute to improve exercise capacity, dyspnea, airway secretion removal, hematosis, reduced acute exacerbations and subsequent hospitalizations in patients with copd. based on these results, the primary aim of this study is to assess whether long-term nasal high flow treatment can help copd patients to better maintain their endurance capacity following a course of pulmonary rehabilitation.

experimental design: patients achieving their last pulmonary rehabilitation session will be approached to participate in this study. eligible patients who agree to participate in the study and sign informed consent will perform two baseline visit assessments: first visit: incremental cardiopulmonary exercise testing. second visit: other baseline assessment (see outcome section), including a constant workload exercise testing at 75% of the maximal workload achieved during the incremental exercise testing. then, patients will then be randomized to one of the following two arms: * nasal high flow, * usual care. after 6 months, patients will be invited to perform the same assessment as during the second baseline visit.

Eligibility criteria:
inclusion criteria: * chronic obstructive pulmonary disease stage iii to iv; * with or without long-term oxygen therapy; * having completed a course of pulmonary rehabilitation within the last 4 weeks (at least 18 sessions). exclusion criteria: * did not complete a course of pulmonary rehabilitation; * using noninvasive ventilation or constant positive airway pressure treatment; * tracheostomy; * nasal high flow intolerance; * pregnancy or likely to be; * unable to consent; * patients under guardianship.

Keywords: chronic obstructive pulmonary disease pulmonary rehabilitation nasal high flow