Nasal High Flow to Maintain the Benefits of Pulmonary Rehabilitation in Chronic Obstructive Pulmonary Disease Patients (PPR-NHF)

Nasal High Flow to Maintain the Benefits of Pulmonary Rehabilitation in Chronic Obstructive Pulmonary Disease Patients

Nasal High Flow to Maintain the Benefits of Pulmonary Rehabilitation in Patients With Severe to Very Severe Chronic Obstructive Pulmonary Disease - A Randomized Controlled Study

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.

Following baseline assessment, patients randomized to the nasal high flow arm will be equipped with a nasal high flow device (myAIRVO2) administrated through the Optiflow nasal canula. Flow will be set at the highest flow tolerated (20-30 L/min): initially 30 L/min, progressively decrease if not tolerated. Temperature will be set between 34-37°C according to the tolerance : initially 37°C and decreased if not tolerated. Patients will be asked to use the device 8h per day. Patients under long-term oxygen will preserve their usual flow. The usual prescribed oxygen flow will then be titrated during nasal high flow to maintain the same baseline transcutaneous oxygen saturation as their conventional oxygen therapy (≥ 90%) to prevent any oxygen dilution effect of nasal high flow.

Patient randomized to the control group will have no other specific intervention than their usual care. Patients under long-term oxygen will preserve their usual flow.

Patients will perform a constant workload exercise testing at 75% of the maximal workload achieved during the incremental cardiopulmonary exercise testing.

Patients will perform a constant workload exercise testing at 75% of the maximal workload achieved during the incremental cardiopulmonary exercise testing.

Quality of life will be assessed using the Saint George's Respiratory Questionnaire. The score range from 0 (worst quality of life) to 100 (optimal quality of life).

Quality of life will be assessed using the Saint George's Respiratory Questionnaire. The score range from 0 (worst quality of life) to 100 (optimal quality of life).

The quality of life will be assessed at baseline and post-intervention for a total time frame of 6month

The number of chronic obstructive pulmonary disease self reported exacerbations experienced by the participants during the 6 months period of follow-up will be assessed.

The number of chronic obstructive pulmonary disease related hospitalizations experienced by the participants during the 6 months period of follow-up will be assessed.

The quadriceps muscle thickness will be assessed at baseline and post-intervention for a total time frame of 6month

The overall muscle function will be assessed using bioimpedance (free fat mass minus total body water)

The distance performed during the six-minute walk test will be assessed post-intervention (after 6months)

Parasternal electromyogram will be used to assess central output during maximal inspiratory and expiratory pressure measurement as during the sniff test. Moreover, parasternal electromyogram will be assessed both at rest and during nasal high flow (30L/min, 34°C).

Parasternal electromyogram will be used to assess central output during maximal inspiratory and expiratory pressure measurement as during the sniff test. Moreover, parasternal electromyogram will be assessed both at rest and during nasal high flow (30L/min, 34°C).

The number of steps per day will be recorded over a course of 14 week days using an activity monitor.

The number of steps per day will be recorded over a course of 14 week days using an activity monitor.

The time spent during activities superior to 3 metabolic equivalent per day will be over a course of 14 week days

The time spent during activities superior to 3 metabolic equivalent per day will be assessed 14 days following inclusion

The time spent during activities superior to 3 metabolic equivalent per day will be over a course of 14 week days

The time spent during activities superior to 3 metabolic equivalent per day will be assessed during 14 days after 6months of intervention

The quality of sleep will be assessed using a aVisual Analogue Scale (ranging from 0 to 10 with 10 indicating higher sleep quality).

The quality of sleep will be assessed using a aVisual Analogue Scale (ranging from 0 to 10 with 10 indicating higher sleep quality).

The quality of sleep using a Visual Analogue Scale will be assessed post-intervention (after 6months)

The quality of sleep will be assessed using the pittsburgh scale which has been validated to assess sleep quality. The scale range from 0 (major sleep difficulties) to 21 (no difficulty).

The quality of sleep will be assessed using the pittsburgh scale which has been validated to assess sleep quality. The scale range from 0 (major sleep difficulties) to 21 (no difficulty).

The number of days that the nasal high flow device was used throughout the follow-up will be assessed post-intervention in the nasal high flow arm for a total time frame of 6 months

The number of hours of utilization per day throughout the follow-up will be assessed post-intervention in the nasal high flow arm for a total time frame of 6 months

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.

Normandie University, UNIROUEN, UPRES EA 3830, Haute Normandie Research and Biomedical Innovation, Rouen, France ; Pulmonary, Thoracic Oncology and Respiratory Intensive Care Department, Rouen University Hospital, Rouen, France

ADIR Association, Rouen University Hospital, Rouen, France ; Normandie University, UNIROUEN, UPRES EA 3830, Haute Normandie Research and Biomedical Innovation, Rouen, France

Normandie University, UNIROUEN, UPRES EA 3830, Haute Normandie Research and Biomedical Innovation, Rouen, France ; Pulmonary, Thoracic Oncology and Respiratory Intensive Care Department, Rouen University Hospital, Rouen, France

ADIR Association, Rouen University Hospital, Rouen, France ; Normandie University, UNIROUEN, UPRES EA 3830, Haute Normandie Research and Biomedical Innovation, Rouen, France

ADIR Association, Rouen University Hospital, Rouen, France ; Normandie University, UNIROUEN, UPRES EA 3830, Haute Normandie Research and Biomedical Innovation, Rouen, France ; Pulmonary, Thoracic Oncology and Respiratory I