Chronic Obstructive Pulmonary Disease (COPD)DEFLA-DYSPNEANCT06956742
Intermittent Intrapulmonary Deflation and Dyspnea Following Exercise in People With Chronic Obstructive Pulmonary Disease
A study testing Active intermittent intrapulmonary deflation. in people with Chronic Obstructive Pulmonary Disease (COPD), run by ADIR Association at 1 site in France.
Trial summary
Chronic obstructive pulmonary disease is a long-term lung condition that causes breathing difficulties. People living with this disease often feel short of breath, especially during physical activity, which can make daily tasks more challenging. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Chronic Obstructive Pulmonary Disease (COPD)
- What is being tested?
- Active intermittent intrapulmonary deflation.
- Type of treatment
- Medical device
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 33 participants
- Where
- 1 siteFrance
- Study dates
- 1 Jun 2025to 28 Feb 2028
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age > 18 years;
- COPD stage GOLD II to IV;
- Had completed a pulmonary rehabilitation programme at the investigational site;
- 6-minute walk test < 350 meters before and/or after completing the pulmonary; rehabilitation program;
- mMRC dyspnea scale ≥ 2;
- Pulmonary hyperinflation (ratio between residual volume to total lung capacity superior to 50%, and either total lung capacity superior to 130% or functional residual capacity superior to 130%);
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- With or without oxygen supplementation;
- Stable condition (no exacerbation or change in treatment in the last 4 weeks);
- Naïve to intermittent intrapulmonary deflation.
- Regulatory criteria (social security affiliation; adult patient who has read and understood the information letter and signed the informed consent form).
- Non-inclusion Criteria:
- Pregnant women or likely to be;
- Patients under guardianship or curatorship;
- Inability to consent;
- Primary diagnosis of another chronic obstructive respiratory disease such as asthma or primary bronchiectasis;
- Orthopedic, neurological, vascular, or neuromuscular conditions that limit walking or require walking aids;
- Severe or unstable cardiovascular disease (uncontrolled cardiac arrhythmias, severe heart failure, recent myocardial infarction, unstable angina);
- Patients actively requiring assistance with inspiration (e.g. ventilatory assistance with endotracheal tube, tracheostomy tube, or ventilated with a mask; patients with neuromuscular disease with respiratory muscle weakness; patients with inability to cough forcefully and independently);
- Hemodynamic instability;
- Recent pneumothorax (within the last 3 months);
- Recent pulmonary or upper airway surgery (within the last month);
- Referral to a pulmonary rehabilitation program in preparation for thoracic surgery (lung volume reduction, lung transplantation, or lung resection for non-small cell lung cancer);
- Use of an electrical mechanical device for airway clearance during the study period (in-exsufflator, high-frequency chest oscillation, etc.);
- Active cancer;
- Severe episode of hemoptysis in the last 3 months;
- Severe tracheomalacia.
Who cannot join
- Withdrawal of consent;
- Acute COPD exacerbation between visits or onset of cardiorespiratory instability;
- Use of an electrical mechanical device for airway clearance during the study period (in-exsufflator, high-frequency chest oscillation, etc.).
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
France1 site, 1 recruiting
- Recruiting
ADIR Association
Rouen, Normandy, 76000
Tristan Bonnevie, PhD, 0235592970 ext. +33, t.bonnevie@adir-hautenormandie.com
Tristan Bonnevie, PhD
About this study
Official title: Effect of Intermittent Intrapulmonary Deflation on the Sensory Dimension of Dyspnea After Exercise in Patients With Chronic Obstructive Pulmonary Disease: A Double-blind, Randomized Crossover Study
Chronic obstructive pulmonary disease is a long-term lung condition that causes breathing difficulties. People living with this disease often feel short of breath, especially during physical activity, which can make daily tasks more challenging. This breathlessness is partly caused by mucus accumulation within the airways and air getting trapped in the lungs. Both of these reduce the amount of fresh air that can enter with each breath and increase the effort required to breathe.
To manage symptoms, people with chronic obstructive pulmonary disease may use medications, oxygen therapy, or be referred to pulmonary rehabilitation programs. These programs often include exercise training, self-management strategies, and airway clearance techniques. While chest physiotherapists typically guide patients in these techniques, certain medical devices can also help individuals manage their condition independently at home.
Read more
One such device uses a method called intermittent intrapulmonary deflation, which involves applying gentle pressure changes through a mouthpiece to help loosen mucus and release trapped air from the lungs. Although some individuals already use this kind of device as part of their daily care, more scientific evidence is needed to determine whether the improvements in airway clearance and reduced air trapping actually lead to measurable relief of breathlessness.
The goal of this clinical trial is to find out whether this type of medical device designed to remove airway mucus and trapped air in the lungs (using intermittent intrapulmonary deflation) can help reduce breathlessness (dyspnea) after physical activity in people with COPD.
The main questions this study aims to answer are:
- Does using the device at home for one week reduce the intensity of breathlessness after walking?
- Does it also improve walking distance, reduce the feeling of muscle fatigue, or increase satisfaction with the airway clearance method?
Researchers will compare the active device to a placebo device that looks and feels identical but does not deliver the active treatment. This comparison will help determine whether the observed effects are due to the device itself or other factors such as expectations or chance.
Participants in this study will be adults diagnosed with moderate to very severe chronic obstructive pulmonary disease. All participants must have recently completed a pulmonary rehabilitation program, continue to experience breathlessness while walking, and show signs of lung hyperinflation (when air remains trapped in the lungs). People will not be included if they have other serious health conditions that could make walking difficult or unsafe, or if they have any contraindications to using the device.
Participants who agree to participante in the study will:
- Attend a visit at the pulmonary rehabilitation center for baseline testing and to learn how to use the device;
- Be randomly assigned to use either the active device or the placebo device at home for 7 days;
- Return to the center for walking tests, lung function tests, and questionnaires about breathing and fatigue;
- After a one-week break, use the device with alternative settings (the one not used in the first phase) for another 7 days;
- Complete a final visit at the end of the study to repeat the same tests.
Participants will also be invited to take part in an ancillary study during their first clinic visit to examine how a single session with the device affects breathlessness immediately after walking.
This research will help determine whether this non-pharmacological, device-based method of clearing mucus and reducing trapped air can bring meaningful improvement in breathlessness for people with chronic obstructive pulmonary disease, especially when used at home. If effective, it may offer a simple and convenient way to help people breathe more comfortably during everyday activities.
Participants will receive compensation for their time and travel.
Read the detailed description
Dyspnea in chronic obstructive pulmonary disease is multifactorial and results from complex pathophysiological mechanisms. A key contributor is dynamic hyperinflation, caused by airflow obstruction and expiratory airway collapse during exertion. Excessive mucus production and impaired mucociliary clearance further contribute to airway obstruction, yet mucus management remains an underexplored therapeutic target.
Current airway clearance techniques, such as manual chest physiotherapy and positive expiratory pressure devices, often require forced expiration and primarily act on proximal airways. In contrast, intermittent intrapulmonary deflation is a novel approach applying intermittent negative pressure during expiration to facilitate secretion mobilization, potentially improving expiratory flow and reducing lung hyperinflation. Intermittent intrapulmonary deflation is active only during passive exhalation, can be self-administered at home, and may provide an alternative for patients chronic pulmonary disease who experience chronic mucus retention.
This study aims to assess the effect of intermittent intrapulmonary deflation on dyspnea after exercise in individuals with chronic obstructive pulmonary disease. By improving secretion clearance and reducing dynamic hyperinflation, intermittent intrapulmonary deflation could represent a novel strategy to alleviate dyspnea, enhance exercise tolerance, quality of life, and address a significant unmet clinical need in this population.
Primary objective: to evaluate the effect of using an intermittent intrapulmonary deflation device for one week at home on the sensory dimension of dyspnea after exercise in individuals with chronic obstructive pulmonary disease.
Secondary objectives: to evaluate the effect of using an intermittent intrapulmonary deflation device for one week at home on exercise capacity, dyspnea perception (affective dimension and dyspnea intensity), perception of lower limb muscle fatigue, breathing pattern, operational lung volume, critical inspiratory constraints, and heart rate measured at the end of exercise. Additionally, the study aims to assess the depth of oxygen desaturation during exercise, participant satisfaction, respiratory function, and adverse events.
This is a prospective, randomized, controlled, double-blind, crossover clinical trial conducted in a single center, with concealed allocation. Participants will undergo two 7-day intervention periods at home (active or placebo device), separated by a minimum of 7days (maximum 28 days) washout phase. Each participant will serve as their own control.
This study will be accompanied by a pre-planned ancillary study designed to evaluate the acute effects of using the intermittent intrapulmonary deflation device on the same outcomes, based on the initial randomization sequence at the first visit. Consequently, this ancillary study is a single-center, randomized controlled, prospective, parallel trial with concealed allocation and double blinding (participants and evaluators).
This clinical trial comprises six phases: an initial visit (visit 1) at the pulmonary rehabilitation center, a one-week home-based treatment period utilizing either the investigational device or the placebo device, an intermediate visit after this first week (visit 2), a washout period (minimum one week, maximum 4 four weeks), a subsequent one-week home-based treatment period with the alternative condition, and a final visit at the center (visit 3). Further details about de content of these visit are available below.
Inclusion visit (visit 1):
The visit is conducted by the recruitment officer who also verifies the patient's eligibility criteria. The recruitment officer also informs the patient and answers all questions regarding the objective, nature of constraints, foreseeable risks, and expected benefits of the clinical investigation. They specify the patient's rights in the context of the clinical investigation and provide a copy of the information note and consent form to the patient.
Before any examination related to the clinical investigation, the recruitment officer obtains the patient's free, informed, and written consent.
This visit follows the 14 steps described below. Steps 8 to 14 belong to a pre-planned ancillary clinical investigation aimed at examining the acute effects of using an intermittent intrapulmonary deflation device on the sensory dimension of dyspnea and other outcomes after exertion, in individuals with chronic obstructive pulmonary disease.
- Information, written consent, and collection of demographic data;
- Assessment of dyspnea at rest, health status, and quality of life;
- Evaluation of respiratory function and breathing pattern at rest in a seated position;
- Installation of a pulse oximeter and performance of a six-minute walk test, with the patient's usual oxygen flow rate;
- Post-exercise assessment: dyspnea and muscle fatigue of the lower limbs, breathing pattern, operational lung volume, and critical inspiratory constraints;
- Familiarization and training on the use of the intermittent intrapulmonary deflation device (SIMEOX, PhysioAssist, Aix-en-Provence, France), and determination of the optimal setting by the operator (device power percentage ranging from 25 to 100% to reach the clinical efficacy indicator); the operator informs the patient that different settings are being studied during the clinical investigation without further details and does not provide indications regarding the clinical efficacy indicator; the operator also ensures that the patient is capable of performing deep and maximal inspiratory maneuvers. This initiation should be time-limited to avoid representing a complete session to minimize any physiological effects.
- Randomisation. Pre-planned ancilliary clinical investigation:
- Assessment of dyspnea ;
- Performance a single 20-minute session with the intermittent intrapulmonary deflation device or with the placebo, according to the randomisation sequence;
- Assessment of dyspnea and muscle fatigue of the lower limbs;
- Evaluation of respiratory function and breathing pattern;
- Installation of a pulse oximeter and performance of the six-minute walk test by an evaluator unaware of the allocation, with the patient's usual oxygen flow rate;
- Post-exercise assessment: dyspnea and muscle fatigue of the lower limbs, breathing pattern, operational volume, and critical inspiratory constraints;
- Assessment of participant's satisfaction.
At the end of this visit, a home healthcare provider will provide the intermittent intrapulmonary deflation device for one week. Patients are invited to use the device independently at home according to the randomization sequence, for 20 minutes, twice daily. A phone appointment is scheduled for the first day of independent use and on the fourth day. Any identified difficulties in use will lead to the scheduling of another appointment the following day.
Follow-up visit at the end of the first sequence (visit 2):
The visit is conducted by the evaluator, who is unaware of the patient's allocation. The details of this visit are described below:
- Assessment of dyspnea and muscle fatigue of the lower limbs;
- Evaluation of respiratory function and breathing pattern, at rest in a seated position;
- Installation of a pulse oximeter and performance of the six-minute walk test by an evaluator unaware of the order in which the patient used the device, with the patient's usual oxygen flow rate;
- Post-exercise assessment: dyspnea and muscle fatigue of the lower limbs, breathing pattern, operational volume, and critical inspiratory constraints;
- Assessment of participant satisfaction.
Washout period:
After the second visit, patients are asked not to use the device for at least one week (maximum four weeks). This is ensured by providing a limited number of consumables that will not allow device use beyond the first week.
At the end of this washout period, the home healthcare provider will return to the patient's home to equip them with the device required for the alternative condition, according to the randomization sequence.
Follow-up visit at the end of the second sequence (visit 3) and conclusion of the research:
The visit is conducted by the evaluator, who is unaware of the patient's allocation. This visit strictly follows the same procedures as visit 2.
At the end of this visit, the research is considered completed, and the home healthcare provider retrieves the device provided to the patient's home.
Randomisation and interventions: the sequence for administering the therapeutic modalities (active device followed by placebo, or placebo followed by active device) will be determined randomly using a computer-generated list (randomizer.org) in alternating blocks of 4 and 6, with a 1:1 ratio. The block sizes will remain undisclosed to the recruiting operator to prevent bias. This list will be maintained by an individual external to the study, who will be contacted by the recruitment operator during patient inclusion to determine the allocation sequence (concealed allocation). A document detailing the randomisation procedure will be kept confidential at the sponsor site.
- Sequence A: active device → washout → placebo device
- Sequence B: placebo device → washout → active device
Active intermittent intrapulmonary deflation sessions will be performed using the SIMEOX device (SIMEOX, PhysioAssist, Aix-en-Provence, France), which will be delivered to the patient's home by a home healthcare provider. The device power setting (25%, 50%, 75%, or 100%) will be individualized according to the parameters determined during the familiarization visit (visit 1). Patients will be instructed to perform tidal volume inspirations followed by passive expirations into the device through a mouthpiece, up to their maximal tolerance. The device will be activated by the patient during expiration using a manual remote control.
Each device usage cycle consists of 10 expirations, with oscillations generated at 12 Hz during the first 8 cycles and at 6 Hz during the last 2 cycles. Rest periods will be allowed during the session, and a mandatory pause will be imposed every 10 expirations. The session duration is fixed at 20 minutes, with patients performing one session in the morning and another in the afternoon or evening.
Placebo intermittent intrapulmonary deflation sessions will be performed using the SIMEOX device (SIMEOX, PhysioAssist, Aix-en-Provence, France), which will be delivered to the patient's home by a home healthcare provider. Due to the physiological mechanism of action of the device (intermittent negative pressure with increasing intensity, inversely proportional to airflow resistance), it is assumed that device use under placebo conditions will be infra-therapeutic.
To ensure this, the device will be set to the same power setting as the active intermittent intrapulmonary deflation session but an intentional air leak will be introduced into the circuit at the device's output (not visible to the participant) to prevent the generated negative pressure from exceeding the minimum effective threshold. The validity of this placebo condition will be confirmed through bench tests.
All other conditions will remain identical to the active intermittent intrapulmonary deflation sessions. Patients will be instructed to perform tidal volume inspirations, followed by passive expirations into the device through a mouthpiece, up to their maximal tolerance. The device will be activated by the patient during expiration using a manual remote control.
Each device usage cycle will consist of 10 expirations, with oscillations generated at 12 Hz during the first 8 cycles and at 6 Hz during the last 2 cycles. Rest periods will be allowed during the session, with a mandatory pause every 10 expirations. The session duration is fixed at 20 minutes, with patients performing one session in the morning and another in the afternoon or evening.
Blinding of the evaluator: evaluations will be conducted by an assessor who is blinded to the order in which the patient has used the device. Data will be recorded in an electronic data collection form (Dotter.Science, KerNel Biomedical) by the assessor, who will remain unaware of the intervention.
Blinding of the participant: due to the physiological mechanism of the device (intermittent negative pressure increasing with resistance to airflow), it is assumed that the use of the device in the placebo condition will be sub-therapeutic. To achieve this, the device will be set to a low power for all participants, and a deliberate leak will be incorporated into the output circuit (invisible to the participant) to ensure that the maximum pressure achieved is below the effective minimum negative pressure (-10 cm H2O). The validity of this placebo condition will be confirmed in advance through bench tests. The remaining modalities will mirror those of the active intermittent intrapulmonary deflation session.
Blinding of the statistician: statistical analyses plan will be defined a priori. Statistical analysis will be conducted by an independent statistician who will be unaware of the randomization sequence.
Sample size calculation for a superiority study based on the primary outcome (sensory dimension of dyspnea assessed using the multidimensional dyspea profile questionnaire): to detect a mean difference of at least 2 points between interventions (corresponding to the established minimal clinically important difference for the primary outcome), and considering a moderate effect size of 0.5, a type I error rate of 5%, and a power of 80%, a total of 33 participants will be required. Accounting for a 15% loss to follow-up, up to 40 participants may be included (20 in each crossover group) to ensure that 33 participants have an available measurement for the primary outcome.
Statistical analysis :
Analysis populations:
Three analysis populations will be involved in this study:
- The full analysis Sst will include all randomized participants with at least one efficacy assessment. For those who do not complete the treatment as planned, the last observation will be used as the final outcome (last observation carried forward).
- The per protocol set will include all randomized participants who completed all visits in accordance with the protocol.
- The adherent population will include all randomized participants who completed at least 70% of the prescribed sessions, which is defined 10 sessions or more.
Description of the population:
Qualitative variables will be described by counts and frequencies. Quantitative variables will be summarized using means, standard deviations, and when justified by the distribution of the variable, medians and quartiles will also be reported.
Analysis of outcomes measured only at the end of exercise (performance during the six-minute walk test, nadir transcutaneous oxygen saturation, etc.):
A mixed linear model will be employed for each outcome. The values obtained during the first 6MWT (at rest before the test when available, and after the test), the order of the tests (first or second test), the sequence order (active first then placebo, or placebo first then active), and the treatment modality (active or placebo) will be included as fixed effects, with the participant included as a random effect.
Analysis of other outcomes:
A mixed linear model will be utilized for each outcome. The values obtained during the first six-minute walk test at rest before the test when available, and after the test, and after exercise), the order of the tests (first or second test), the sequence order (active first then placebo, or placebo first then active), the treatment modality (active or placebo), the time of measurement (baseline or post-exercise), and the interaction between treatment modality and time of measurement will be included as fixed effects, with the participant as a random effect.
Analysis of ancillary study endpoints:
The ancillary study will also focus on the primary endpoint and secondary endpoints measured before and/or after the 6MWT, after randomization. A mixed linear model or a mixed logistic model will be used. In this model, the treatment modality (active or placebo) and values obtained during the first 6MWT at inclusion will be included as fixed effects, with the participant as a random effect for variables collected only at the end of exercise. For values measured before and after exercise, the time of measurement (baseline or post-exercise) and the interaction between treatment modality and time of measurement will also be included as fixed effects.
Note 1: the values obtained during the first 6MWT at inclusion are the values at inclusion for each criterion before and after the 6MWT at inclusion. For example, for the primary endpoint, we will use the values of the sensory dimension of dyspnea at inclusion (at rest before the test, and at the end of the test).
Note 2: Statistical models may take into account the interaction between treatment modality and treatment sequence.
The effect of intermittent intrapulmonary pressure release on the proportion of patients with a desaturation of ≥4% will be studied using the McNemar test.
Presentation of results Data will be reported as mean differences (95% confidence intervals) and interpreted according to the minimal clinically important difference for each criterion (when available in the literature) or based on the clinical expertise of the investigators.
Secondary analysis A dose-response analysis will be conducted. The number of sessions will be considered as the dose and the primary endpoint as the response.
Sensitivity analysis A sensitivity analysis will be conducted to assess the influence of various factors, such as the use of inhaled treatments (all types of bronchodilators and anticholinergics), GOLD stage, the presence or absence of oxygen therapy and/or non-invasive ventilation, participant age, or secretory phenotype (based on a COPD Assessment Test score ≥ 6 from the sum of questions 1 and 2, or the Saint George's Respiratory Questionnaire score).
Analyses will be performed using GraphPad Prism 8 and R software.
- Being tested
- Active intermittent intrapulmonary deflation., Placebo intermittent intrapulmonary deflation.
- Keywords
- COPD, Chronic obstructive pulmonary disease, Intermittent intrapulmonary deflation, Dypsnea, Exercise
- Medical subject headings
- Pulmonary Disease, Chronic Obstructive, Motor Activity
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Active intermittent intrapulmonary deflation.Device
Intermittent intrapulmonary deflation sessions will be performed using the SIMEOX device (SIMEOX, PhysioAssist, Aix-en-Provence, France), which will be delivered to the patient's home by a home healthcare provider. The device power setting (25%, 50%, 75%, or 100%) will be individualized according to the parameters determined during the familiarization visit by a trained physiotherapist. Patients will be instructed to perform tidal volume inspirations followed by passive expirations into the device through a mouthpiece, up to their maximal tolerance. The device will be activated by the patient during expiration using a manual remote control.
Each device usage cycle consists of 10 expirations, with oscillations generated at 12 Hz during the first 8 cycles and at 6 Hz during the last 2 cycles. Rest periods will be allowed during the session, and a mandatory pause will be imposed every 10 expirations. The session duration is fixed at 20 minutes, with patients performing one session in the
Placebo intermittent intrapulmonary deflation.Device
Placebo intermittent intrapulmonary deflation sessions will be performed using the SIMEOX device (SIMEOX, PhysioAssist, Aix-en-Provence, France), which will be delivered to the patient's home by a home healthcare provider. Due to the physiological mechanism of action of the device (intermittent negative pressure with increasing intensity, inversely proportional to airflow resistance), it is assumed that device use under placebo conditions will be infra-therapeutic.
To ensure this, the device will be set to the same setting as the active intermittent intrapulmonary deflation session but an intentional air leak will be introduced into the circuit at the device's output (not visible to the participant) to prevent the generated negative pressure from exceeding t The validity of this placebo condition will be confirmed through bench tests.
All other conditions will remain identical to the active intermittent intrapulmonary deflation sessions. Patients will be instructed to perform tidal vo
| Study group | Role | What they receive |
|---|---|---|
| Active intermittent intrapulmonary deflation | Experimental | One week home-based treatment period. Receives: Device: Active intermittent intrapulmonary deflation. |
| Placebo intermittent intrapulmonary deflation | Placebo comparator | One week home-based treatment period. Receives: Device: Placebo intermittent intrapulmonary deflation. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Sensory dimension of dyspnea
The sensory dimension of dyspnea will be assessed using French version of the Multidimensional Dyspnea Profile questionnaire, taking into account the last 30 seconds of effort during the 6-minute walk test to complete the questionnaire. This self-administered questionnaire can yield scores ranging from 0 to 10, with higher scores indicating a greater sensory dimension of dyspnea. The established minimal clinically important difference for this outcome is 2 points.
Measured: Day 8 (after seven days of intervention)
Secondary outcomes (63)
Functional exercise capacity - Six-minute walk test
Functional exercise capacity will be evaluated using the 6-minute walk test. It will be conducted following the guidelines of the American Thoracic Society and the European Respiratory Society. Patients will be instructed to cover the maximum distance possible within 6 minutes. The test will be performed in a corridor with a minimum length of 30 meters. The established minimal clinically important difference for this test is 25 meters.
Measured: Day 8 (after seven days of intervention).
Affective dimension of dyspnea
The affective dimension of dyspnea will be assessed using the french version of the Multidimensional Dyspnea Profile questionnaire, considering the last 30 seconds of effort during the 6-minute walk test to complete the questionnaire. This self-administered questionnaire can yield scores ranging from 0 to 10, with higher scores indicating a significant affective dimension of dyspnea. The established minimal clinically important difference for this outcome is 3 points.
Measured: Day 8 (after seven days of intervention).
Intensity of dyspnea
The intensity of dyspnea will be evaluated using the Borg scale, which ranges from 0 to 10. This scale allows for values between 0 (absence of breathlessness) and 10 (maximal breathlessness). Patients will be asked, "What is the intensity of your breathlessness?" The minimal clinically important difference for this outcome is 1 point. Outcome will be assessed at the end of the six-minute walk test.
Measured: Day 8 (after seven days of intervention).
Intensity of lower limb fatigue
The intensity of muscle fatigue in the lower limbs will be assessed using the Borg scale, which ranges from 0 to 10. This scale allows for values between 0 (absence of fatigue) and 10 (maximal fatigue). Patients will be asked, "What is the intensity of the fatigue in your legs?" The minimal clinically important difference for this outcome is 1 point. Outcome will be assessed at the end of the six-minute walk test.
Measured: Day 8 (after seven days of intervention).
Respiratory function - Forced expiratory volume in 1 second
Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: Day 8 (after seven days of intervention).
Respiratory function - Vital capacity
Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: Day 8 (after seven days of intervention).
Respiratory function - Forced vital capacity
Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: Day 8 (after seven days of intervention).
Respiratory function - Ratio between forced expiratory volume in 1 second to forced vital capacity
Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France).
Measured: Day 8 (after seven days of intervention).
Respiratory function - Functional residual capacity
Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: Day 8 (after seven days of intervention).
Respiratory function - Total lung capacity
Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: Day 8 (after seven days of intervention).
Respiratory function - Residual volume
Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: Day 8 (after seven days of intervention).
Respiratory function - Airway resistance
Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France).
Measured: Day 8 (after seven days of intervention).
Breathing pattern - Tidal volume
Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds.
Measured: Day 8 (after seven days of intervention).
Breathing pattern - Respiratory rate
Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds.
Measured: Day 8 (after seven days of intervention).
Breathing pattern - Inspiratory time
Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds.
Measured: Day 8 (after seven days of intervention).
Breathing pattern - Expiratory time
Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds.
Measured: Day 8 (after seven days of intervention).
Breathing pattern - Ratio between inspiratory time to expiratory time
Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds.
Measured: Day 8 (after seven days of intervention).
Breathing pattern - Minute ventilation
Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds. Minute ventilation will be calculated as the product of tidal volume and respiratory rate.
Measured: Day 8 (after seven days of intervention).
Operational lung volume - Inspiratory capacity
Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
Measured: Day 8 (after seven days of intervention).
Operational lung volume - End inspiratory lung volume
Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
End inspiratory lung volume will be calculated as total lung capacity - inspiratory capacity + tidal volume.
Measured: Day 8 (after seven days of intervention).
Operational lung volume - End expiratory lung volume
Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
End expiratory lung volume will be calculated as total lung capacity - inspiratory capacity.
Measured: Day 8 (after seven days of intervention).
Critical inspiratory constraints - Ratio between tidal volume to inspiratory capacity
Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
Measured: Day 8 (after seven days of intervention).
Critical inspiratory constraints - Ratio between tidal volume to vital capacity
Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
Measured: Day 8 (after seven days of intervention).
Critical inspiratory constraints - Inspiratory reserve volume
Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
Inspiratory reserve volume will be calculated as inspiratory capacity - tidal volume.
Measured: Day 8 (after seven days of intervention).
Critical inspiratory constraints - Ratio between inspiratory reserve volume to total lung capacity
Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
Measured: Day 8 (after seven days of intervention).
Transcutaneous oxygen saturation during a six-minute walk test
Transcutaneous oxygen saturation (SpO₂) will be measured at rest and continuously throughout the 6-minute walk test using a pulse oximeter (Nonin WristOx2 3150, Nonin Medical Inc., Plymouth, MN, USA). Data collection will be performed using Nvision software (Henrotch, Aartselaar, Belgium). The SpO₂ value at the end of the test, as well as the nadir SpO₂ (lowest recorded value) during the 6MWT, will be reported. The proportion of patients experiencing oxygen desaturation ≥ 4%, as well as the proportion of patients with desaturation ≥ 4% and SpO₂ < 90%, will also be documented. Finally, the total time spent with SpO₂ < 90% will be analyzed.
Measured: Day 8 (after seven days of intervention).
Heart rate during the six-minute walk test
Heart rate will be measured at rest and continuously throughout the six minute xalk test using a pulse oximeter (Nonin WristOx2 3150, Nonin Medical Inc., Plymouth, MN, USA). Data collection will be performed using Nvision software (Henrotch, Aartselaar, Belgium). The highest HR recorded during the test and the HR at the end of the test will be reported.
Measured: Day 8 (after seven days of intervention).
Patient satisfaction
Patient satisfaction will be assessed using a visual analog scale ranging from 0 (not satisfied at all) to 10 (extremely satisfied). Satisfaction will be evaluated at the beginning of follow-up visits and after the 6-minute walk test in the ancillary study.
The question asked will be: "How satisfied are you with the use of the bronchial drainage device to improve your breathlessness?"
Measured: Day 8 (after seven days of intervention).
Health status
Health status will be assessed using the COPD Assessment Test. The CAT score ranges from 0 to 40, with higher values indicating greater impairment of health status. The established minimal clinically important difference for this questionnaire is -2.5 points.
Measured: Day 8 (after seven days of intervention).
Health related quality of life
Quality of life will be assessed using the Saint George's Respiratory Questionnaire. This self-administered questionnaire ranges from 0 to 100, with higher values indicating greater impairment in health-related quality of life. The established minimal clinically important difference for this questionnaire has been established at -4 points.
Measured: Day 8 (after seven days of intervention).
Use of the intermittent intrapulmonary deflation device
Device use will be evaluated through a data collection form that patients will be required to complete after each session. Patients will report the number of sessions per day and the duration of each session.
Additionally, the number of device uses will be estimated based on consumables, which ensure usage tracking for hygiene reasons and indicate when replacement is necessary.
Measured: Day 8 (after seven days of intervention).
Adverse events
Adverse events occurring during the study, whether related or unrelated to the investigated intervention, will be systematically collected and documented.
Measured: Day 8 (after seven days of intervention).
Weight of secretions
Ancillary study. This outcome measure is specific to the ancillary study. The weight of spontaneously expectorated bronchial secretions after the use of the intermittent intrapulmonary deflation device will be assessed over a 1-hour period following the session.
Saliva will be extracted using a 1 mL micropipette (Pos-D, Mettler Toledo, Viroflay, France), and weight (precision balance, accurate to 0.01 g) of the collected sample will be measured.
Measured: During visit 1 (day 1).
Volume of secretions
Ancillary study. This outcome measure is specific to the ancillary study. The weight of spontaneously expectorated bronchial secretions after the use of the intermittent intrapulmonary deflation device will be assessed over a 1-hour period following the session.
Saliva will be extracted using a 1 mL micropipette (Pos-D, Mettler Toledo, Viroflay, France), and volume (rounded to the nearest mL using a 1 mL micropipette) of the collected sample will be measured.
Measured: During visit 1 (day 1).
Sensory dimension of dyspnea
Ancillary study. The sensory dimension of dyspnea will be assessed using French version of the Multidimensional Dyspnea Profile questionnaire, taking into account the last 30 seconds of effort during the 6-minute walk test to complete the questionnaire. This self-administered questionnaire can yield scores ranging from 0 to 10, with higher scores indicating a greater sensory dimension of dyspnea. The established minimal clinically important difference for this outcome is 2 points.
Measured: During visit 1 (day 1).
Affective dimension of dyspnea
Ancillary study. The affective dimension of dyspnea will be assessed using the french version of the Multidimensional Dyspnea Profile questionnaire, considering the last 30 seconds of effort during the 6-minute walk test to complete the questionnaire. This self-administered questionnaire can yield scores ranging from 0 to 10, with higher scores indicating a significant affective dimension of dyspnea. The established minimal clinically important difference for this outcome is 3 points.
Measured: During visit 1 (day 1).
Functional exercise capacity - Six-minute walk test
Ancillary study. Functional exercise capacity will be evaluated using the 6-minute walk test. It will be conducted following the guidelines of the American Thoracic Society and the European Respiratory Society. Patients will be instructed to cover the maximum distance possible within 6 minutes. The test will be performed in a corridor with a minimum length of 30 meters. The established minimal clinically important difference for this test is 25 meters.
Measured: During visit 1 (day 1).
Intensity of dyspnea
Ancillary study. The intensity of dyspnea will be evaluated using the Borg scale, which ranges from 0 to 10. This scale allows for values between 0 (absence of breathlessness) and 10 (maximal breathlessness). Patients will be asked, "What is the intensity of your breathlessness?" The minimal clinically important difference for this outcome is 1 point. Outcome will be assessed at the end of the six-minute walk test.
Measured: During visit 1 (day 1).
Intensity of lower limb fatigue
Ancillary study. The intensity of muscle fatigue in the lower limbs will be assessed using the Borg scale, which ranges from 0 to 10. This scale allows for values between 0 (absence of fatigue) and 10 (maximal fatigue). Patients will be asked, "What is the intensity of the fatigue in your legs?" The minimal clinically important difference for this outcome is 1 point. Outcome will be assessed at the end of the six-minute walk test.
Measured: During visit 1 (day 1).
Respiratory function - Forced expiratory volume in 1 second
Ancillary study. Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: During visit 1 (day 1).
Respiratory function - Vital capacity
Ancillary study. Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: During visit 1 (day 1).
Respiratory function - Forced vital capacity
Ancillary study. Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: During visit 1 (day 1).
Respiratory function - Ratio between forced expiratory volume in 1 second to forced vital capacity
Ancillary study. Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France).
Measured: During visit 1 (day 1).
Respiratory function - Functional residual capacity
Ancillary study. Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: During visit 1 (day 1).
Respiratory function - Total lung capacity
Ancillary study. Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: During visit 1 (day 1).
Respiratory function - Residual volume
Ancillary study. Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France). The values will be expressed liters as well as a percentage of the theoretical values determined by the Global Lung Function Initiative of the European Respiratory Society
Measured: During visit 1 (day 1).
Respiratory function - Airway resistance
Ancillary study. Respiratory function will be evaluated through pulmonary function testing conducted in accordance with international guidelines using a validated plethysmograph (Minibox+TM, PulmOne, Nîmes, France).
Measured: During visit 1 (day 1).
Breathing pattern - Tidal volume
Ancillary study. Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds.
Measured: During visit 1 (day 1).
Breathing pattern - Respiratory rate
Ancillary study. Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds.
Measured: During visit 1 (day 1).
Breathing pattern - Inspiratory time
Ancillary study. Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds.
Measured: During visit 1 (day 1).
Breathing pattern - Expiratory time
Ancillary study. Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds.
Measured: During visit 1 (day 1).
Breathing pattern - Ratio between inspiratory time to expiratory time
Ancillary study. Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds.
Measured: During visit 1 (day 1).
Breathing pattern - Minute ventilation
Ancillary study. Breathing pattern will be recorded using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) at rest and at the end of the exercise while seated. Data will be acquired via an analog-to-digital converter (Powerlab, AD Instruments, Chalgrove, UK), and the acquisition system will be calibrated before each participant.
To perform the resting measurements, participants will be fitted with a nose clip and instructed to breathe quietly for a period of five minutes through the pneumotachograph. The most stable minute will be selected for analysis. The measurement will be repeated immediately following the 6-minute walk test over a duration of 30 seconds. Minute ventilation will be calculated as the product of tidal volume and respiratory rate.
Measured: During visit 1 (day 1).
Operational lung volume - Inspiratory capacity
Ancillary study. Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
Measured: During visit 1 (day 1).
Operational lung volume - End inspiratory lung volume
Ancillary study. Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
End inspiratory lung volume will be calculated as total lung capacity - inspiratory capacity + tidal volume.
Measured: During visit 1 (day 1).
Operational lung volume - End expiratory lung volume
Ancillary study. Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
End expiratory lung volume will be calculated as total lung capacity - inspiratory capacity.
Measured: During visit 1 (day 1).
Critical inspiratory constraints - Ratio between tidal volume to inspiratory capacity
Ancillary study. Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
Measured: During visit 1 (day 1).
Critical inspiratory constraints - Ratio between tidal volume to vital capacity
Ancillary study. Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
Measured: During visit 1 (day 1).
Critical inspiratory constraints - Inspiratory reserve volume
Ancillary study. Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
Inspiratory reserve volume will be calculated as inspiratory capacity - tidal volume.
Measured: During visit 1 (day 1).
Critical inspiratory constraints - Ratio between inspiratory reserve volume to total lung capacity
Ancilary study. Assuming that total lung capacity remains unchanged during exercise, inspiratory capacity will be utilized as a marker of dynamic hyperinflation to estimate operational lung volumes. The measurement of inspiratory capacity will be conducted using a pneumotachograph (MLT1000L, AD Instruments, Oxford, UK) following the same protocols as the assessment of the breathing pattern.
This measurement will be performed at rest, immediately following the five minutes of calm breathing. Five maximal inspiratory maneuvers will be conducted from functional residual capacity, and the highest value will be used for analysis. The inspiratory capacity measurement will also be repeated immediately after the completion of the 6-minute walk test, with three measurements taken.
Measured: During visit 1 (day 1).
Transcutaneous oxygen saturation during a six-minute walk test
Ancillary study. Transcutaneous oxygen saturation (SpO₂) will be measured at rest and continuously throughout the 6-minute walk test using a pulse oximeter (Nonin WristOx2 3150, Nonin Medical Inc., Plymouth, MN, USA). Data collection will be performed using Nvision software (Henrotch, Aartselaar, Belgium). The SpO₂ value at the end of the test, as well as the nadir SpO₂ (lowest recorded value) during the 6MWT, will be reported. The proportion of patients experiencing oxygen desaturation ≥ 4%, as well as the proportion of patients with desaturation ≥ 4% and SpO₂ < 90%, will also be documented. Finally, the total time spent with SpO₂ < 90% will be analyzed.
Measured: During visit 1 (day 1).
Heart rate during the six-minute walk test
Ancillary study. Heart rate will be measured at rest and continuously throughout the six minute xalk test using a pulse oximeter (Nonin WristOx2 3150, Nonin Medical Inc., Plymouth, MN, USA). Data collection will be performed using Nvision software (Henrotch, Aartselaar, Belgium). The highest HR recorded during the test and the HR at the end of the test will be reported.
Measured: During visit 1 (day 1).
Patient satisfaction
Ancillary study. Patient satisfaction will be assessed using a visual analog scale ranging from 0 (not satisfied at all) to 10 (extremely satisfied). Satisfaction will be evaluated at the beginning of follow-up visits and after the 6-minute walk test in the ancillary study.
The question asked will be: "How satisfied are you with the use of the bronchial drainage device to improve your breathlessness?"
Measured: During visit 1 (day 1).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 May 2025
- Study start1 Jun 2025
- Primary completion28 Feb 2028 (estimated)
- Study completion28 Feb 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Chronic Obstructive Pulmonary Disease (COPD)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Single-center, randomized controlled, prospective, two-arm crossover trial with concealed allocation and double-blinding (participants and evaluators). This study will be accompanied by a pre-planned ancillary study designed to evaluate the acute effects of using the intermittent intrapulmonary deflation device on the same outcomes, based on the initial randomization sequence at the first visit (see Study Description section). Consequently, this ancillary study is a single-center, randomized controlled, prospective, parallel trial with concealed allocation and double blinding (participants and evaluators).
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 33 participants (estimated)
Sponsor and investigators
- Lead sponsor
- ADIR Association
- Sponsor type
- University, hospital or other
- Collaborators
- PhysioAssist
- Responsible party
- Sponsor
- Investigators
- Tristan Bonnevie, PhD, Principal investigator, Association ADIRFrancis-Edouard Gravier, PhD, Study chair, ADIR AssociationAntoine Cuvelier, Professor, Study chair, ADIR AssociationJean-François Muir, Professor, Study chair, ADIR AssociationAstrid Vanheule, Msc student, Study chair, ADIR Association
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06956742
- Sponsor's protocol ID
- DEFLA-DYSPNEA
- Acronym
- DEFLA-DYSPNEA
- Status last verified
- May 2026
- First submitted
- 24 Apr 2025
- Last updated
- 2 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Data will be made available upon reasonable request for research purposes after publication. This includes de-identified data related to demographic characteristics, as well as endpoints published either in the main manuscript or any supplemental data. Requests should be sent to Dr T. Bonnevie (t.bonnevie@adir-hautenormandie.com).
Publications
Ekstrom MP, Bornefalk H, Skold CM, Janson C, Blomberg A, Bornefalk-Hermansson A, Igelstrom H, Sandberg J, Sundh J. Minimal Clinically Important Differences and Feasibility of Dyspnea-12 and the Multidimensional Dyspnea Profile in Cardiorespiratory Disease. J Pain Symptom Manage. 2020 Nov;60(5):968-975.e1. doi: 10.1016/j.jpainsymman.2020.05.028. Epub 2020 Jun 6.
PubMed 32512047
Study at a glance
From the registry record, last updated by the sponsor on 2 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effect of Intermittent Intrapulmonary Deflation on the Sensory Dimension of Dyspnea After Exercise in Patients With Chronic Obstructive Pulmonary Disease: A Double-blind, Randomized Crossover Study
- ClinicalTrials.gov ID
- NCT06956742
- Acronym / sponsor ID
- DEFLA-DYSPNEA / DEFLA-DYSPNEA
- Keywords
- COPD, Chronic obstructive pulmonary disease, Intermittent intrapulmonary deflation, Dypsnea, Exercise
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 33 participants (estimated)
- Lead sponsor
- ADIR AssociationUniversity, hospital or other
- Collaborators
- PhysioAssist
- Study start
- 1 Jun 2025 (actual)
- Primary completion
- 28 Feb 2028 (estimated)
- Study completion
- 28 Feb 2028 (estimated)
- First posted
- 4 May 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Chronic obstructive pulmonary disease is a long-term lung condition that causes breathing difficulties. People living with this disease often feel short of breath, especially during physical activity, which can make daily tasks more challenging. This breathlessness is partly caused by mucus accumulation within the airways and air getting trapped in the lungs. Both of these reduce the amount of fresh air that can enter with each breath and increase the effort required to breathe.
To manage symptoms, people with chronic obstructive pulmonary disease may use medications, oxygen therapy, or be referred to pulmonary rehabilitation programs. These programs often include exercise training, self-management strategies, and airway clearance techniques. While chest physiotherapists typically guide patients in these techniques, certain medical devices can also help individuals manage their condition independently at home.
One such device uses a method called intermittent intrapulmonary deflation, which involves applying gentle pressure changes through a mouthpiece to help loosen mucus and release trapped air from the lungs. Although some individuals already use this kind of device as part of their daily care, more scientific evidence is needed to determine whether the improvements in airway clearance and reduced air trapping actually lead to measurable relief of breathlessness.
The goal of this clinical trial is to find out whether this type of medical device designed to remove airway mucus and trapped air in the lungs (using intermittent intrapulmonary deflation) can help reduce breathlessness (dyspnea) after physical activity in people with COPD.
The main questions this study aims to answer are:
- Does using the device at home for one week reduce the intensity of breathlessness after walking?
- Does it also improve walking distance, reduce the feeling of muscle fatigue, or increase satisfaction with the airway clearance method?
Researchers will compare the active device to a placebo device that looks and feels identical but does not deliver the active treatment. This comparison will help determine whether the observed effects are due to the device itself or other factors such as expectations or chance.
Participants in this study will be adults diagnosed with moderate to very severe chronic obstructive pulmonary disease. All participants must have recently completed a pulmonary rehabilitation program, continue to experience breathlessness while walking, and show signs of lung hyperinflation (when air remains trapped in the lungs). People will not be included if they have other serious health conditions that could make walking difficult or unsafe, or if they have any contraindications to using the device.
Participants who agree to participante in the study will:
- Attend a visit at the pulmonary rehabilitation center for baseline testing and to learn how to use the device;
- Be randomly assigned to use either the active device or the placebo device at home for 7 days;
- Return to the center for walking tests, lung function tests, and questionnaires about breathing and fatigue;
- After a one-week break, use the device with alternative settings (the one not used in the first phase) for another 7 days;
- Complete a final visit at the end of the study to repeat the same tests.
Participants will also be invited to take part in an ancillary study during their first clinic visit to examine how a single session with the device affects breathlessness immediately after walking.
This research will help determine whether this non-pharmacological, device-based method of clearing mucus and reducing trapped air can bring meaningful improvement in breathlessness for people with chronic obstructive pulmonary disease, especially when used at home. If effective, it may offer a simple and convenient way to help people breathe more comfortably during everyday activities.
Participants will receive compensation for their time and travel.
Detailed description
Dyspnea in chronic obstructive pulmonary disease is multifactorial and results from complex pathophysiological mechanisms. A key contributor is dynamic hyperinflation, caused by airflow obstruction and expiratory airway collapse during exertion. Excessive mucus production and impaired mucociliary clearance further contribute to airway obstruction, yet mucus management remains an underexplored therapeutic target.
Current airway clearance techniques, such as manual chest physiotherapy and positive expiratory pressure devices, often require forced expiration and primarily act on proximal airways. In contrast, intermittent intrapulmonary deflation is a novel approach applying intermittent negative pressure during expiration to facilitate secretion mobilization, potentially improving expiratory flow and reducing lung hyperinflation. Intermittent intrapulmonary deflation is active only during passive exhalation, can be self-administered at home, and may provide an alternative for patients chronic pulmonary disease who experience chronic mucus retention.
This study aims to assess the effect of intermittent intrapulmonary deflation on dyspnea after exercise in individuals with chronic obstructive pulmonary disease. By improving secretion clearance and reducing dynamic hyperinflation, intermittent intrapulmonary deflation could represent a novel strategy to alleviate dyspnea, enhance exercise tolerance, quality of life, and address a significant unmet clinical need in this population.
Primary objective: to evaluate the effect of using an intermittent intrapulmonary deflation device for one week at home on the sensory dimension of dyspnea after exercise in individuals with chronic obstructive pulmonary disease.
Secondary objectives: to evaluate the effect of using an intermittent intrapulmonary deflation device for one week at home on exercise capacity, dyspnea perception (affective dimension and dyspnea intensity), perception of lower limb muscle fatigue, breathing pattern, operational lung volume, critical inspiratory constraints, and heart rate measured at the end of exercise. Additionally, the study aims to assess the depth of oxygen desaturation during exercise, participant satisfaction, respiratory function, and adverse events.
This is a prospective, randomized, controlled, double-blind, crossover clinical trial conducted in a single center, with concealed allocation. Participants will undergo two 7-day intervention periods at home (active or placebo device), separated by a minimum of 7days (maximum 28 days) washout phase. Each participant will serve as their own control.
This study will be accompanied by a pre-planned ancillary study designed to evaluate the acute effects of using the intermittent intrapulmonary deflation device on the same outcomes, based on the initial randomization sequence at the first visit. Consequently, this ancillary study is a single-center, randomized controlled, prospective, parallel trial with concealed allocation and double blinding (participants and evaluators).
This clinical trial comprises six phases: an initial visit (visit 1) at the pulmonary rehabilitation center, a one-week home-based treatment period utilizing either the investigational device or the placebo device, an intermediate visit after this first week (visit 2), a washout period (minimum one week, maximum 4 four weeks), a subsequent one-week home-based treatment period with the alternative condition, and a final visit at the center (visit 3). Further details about de content of these visit are available below.
Inclusion visit (visit 1):
The visit is conducted by the recruitment officer who also verifies the patient's eligibility criteria. The recruitment officer also informs the patient and answers all questions regarding the objective, nature of constraints, foreseeable risks, and expected benefits of the clinical investigation. They specify the patient's rights in the context of the clinical investigation and provide a copy of the information note and consent form to the patient.
Before any examination related to the clinical investigation, the recruitment officer obtains the patient's free, informed, and written consent.
This visit follows the 14 steps described below. Steps 8 to 14 belong to a pre-planned ancillary clinical investigation aimed at examining the acute effects of using an intermittent intrapulmonary deflation device on the sensory dimension of dyspnea and other outcomes after exertion, in individuals with chronic obstructive pulmonary disease.
- Information, written consent, and collection of demographic data;
- Assessment of dyspnea at rest, health status, and quality of life;
- Evaluation of respiratory function and breathing pattern at rest in a seated position;
- Installation of a pulse oximeter and performance of a six-minute walk test, with the patient's usual oxygen flow rate;
- Post-exercise assessment: dyspnea and muscle fatigue of the lower limbs, breathing pattern, operational lung volume, and critical inspiratory constraints;
- Familiarization and training on the use of the intermittent intrapulmonary deflation device (SIMEOX, PhysioAssist, Aix-en-Provence, France), and determination of the optimal setting by the operator (device power percentage ranging from 25 to 100% to reach the clinical efficacy indicator); the operator informs the patient that different settings are being studied during the clinical investigation without further details and does not provide indications regarding the clinical efficacy indicator; the operator also ensures that the patient is capable of performing deep and maximal inspiratory maneuvers. This initiation should be time-limited to avoid representing a complete session to minimize any physiological effects.
- Randomisation. Pre-planned ancilliary clinical investigation:
- Assessment of dyspnea ;
- Performance a single 20-minute session with the intermittent intrapulmonary deflation device or with the placebo, according to the randomisation sequence;
- Assessment of dyspnea and muscle fatigue of the lower limbs;
- Evaluation of respiratory function and breathing pattern;
- Installation of a pulse oximeter and performance of the six-minute walk test by an evaluator unaware of the allocation, with the patient's usual oxygen flow rate;
- Post-exercise assessment: dyspnea and muscle fatigue of the lower limbs, breathing pattern, operational volume, and critical inspiratory constraints;
- Assessment of participant's satisfaction.
At the end of this visit, a home healthcare provider will provide the intermittent intrapulmonary deflation device for one week. Patients are invited to use the device independently at home according to the randomization sequence, for 20 minutes, twice daily. A phone appointment is scheduled for the first day of independent use and on the fourth day. Any identified difficulties in use will lead to the scheduling of another appointment the following day.
Follow-up visit at the end of the first sequence (visit 2):
The visit is conducted by the evaluator, who is unaware of the patient's allocation. The details of this visit are described below:
- Assessment of dyspnea and muscle fatigue of the lower limbs;
- Evaluation of respiratory function and breathing pattern, at rest in a seated position;
- Installation of a pulse oximeter and performance of the six-minute walk test by an evaluator unaware of the order in which the patient used the device, with the patient's usual oxygen flow rate;
- Post-exercise assessment: dyspnea and muscle fatigue of the lower limbs, breathing pattern, operational volume, and critical inspiratory constraints;
- Assessment of participant satisfaction.
Washout period:
After the second visit, patients are asked not to use the device for at least one week (maximum four weeks). This is ensured by providing a limited number of consumables that will not allow device use beyond the first week.
At the end of this washout period, the home healthcare provider will return to the patient's home to equip them with the device required for the alternative condition, according to the randomization sequence.
Follow-up visit at the end of the second sequence (visit 3) and conclusion of the research:
The visit is conducted by the evaluator, who is unaware of the patient's allocation. This visit strictly follows the same procedures as visit 2.
At the end of this visit, the research is considered completed, and the home healthcare provider retrieves the device provided to the patient's home.
Randomisation and interventions: the sequence for administering the therapeutic modalities (active device followed by placebo, or placebo followed by active device) will be determined randomly using a computer-generated list (randomizer.org) in alternating blocks of 4 and 6, with a 1:1 ratio. The block sizes will remain undisclosed to the recruiting operator to prevent bias. This list will be maintained by an individual external to the study, who will be contacted by the recruitment operator during patient inclusion to determine the allocation sequence (concealed allocation). A document detailing the randomisation procedure will be kept confidential at the sponsor site.
- Sequence A: active device → washout → placebo device
- Sequence B: placebo device → washout → active device
Active intermittent intrapulmonary deflation sessions will be performed using the SIMEOX device (SIMEOX, PhysioAssist, Aix-en-Provence, France), which will be delivered to the patient's home by a home healthcare provider. The device power setting (25%, 50%, 75%, or 100%) will be individualized according to the parameters determined during the familiarization visit (visit 1). Patients will be instructed to perform tidal volume inspirations followed by passive expirations into the device through a mouthpiece, up to their maximal tolerance. The device will be activated by the patient during expiration using a manual remote control.
Each device usage cycle consists of 10 expirations, with oscillations generated at 12 Hz during the first 8 cycles and at 6 Hz during the last 2 cycles. Rest periods will be allowed during the session, and a mandatory pause will be imposed every 10 expirations. The session duration is fixed at 20 minutes, with patients performing one session in the morning and another in the afternoon or evening.
Placebo intermittent intrapulmonary deflation sessions will be performed using the SIMEOX device (SIMEOX, PhysioAssist, Aix-en-Provence, France), which will be delivered to the patient's home by a home healthcare provider. Due to the physiological mechanism of action of the device (intermittent negative pressure with increasing intensity, inversely proportional to airflow resistance), it is assumed that device use under placebo conditions will be infra-therapeutic.
To ensure this, the device will be set to the same power setting as the active intermittent intrapulmonary deflation session but an intentional air leak will be introduced into the circuit at the device's output (not visible to the participant) to prevent the generated negative pressure from exceeding the minimum effective threshold. The validity of this placebo condition will be confirmed through bench tests.
All other conditions will remain identical to the active intermittent intrapulmonary deflation sessions. Patients will be instructed to perform tidal volume inspirations, followed by passive expirations into the device through a mouthpiece, up to their maximal tolerance. The device will be activated by the patient during expiration using a manual remote control.
Each device usage cycle will consist of 10 expirations, with oscillations generated at 12 Hz during the first 8 cycles and at 6 Hz during the last 2 cycles. Rest periods will be allowed during the session, with a mandatory pause every 10 expirations. The session duration is fixed at 20 minutes, with patients performing one session in the morning and another in the afternoon or evening.
Blinding of the evaluator: evaluations will be conducted by an assessor who is blinded to the order in which the patient has used the device. Data will be recorded in an electronic data collection form (Dotter.Science, KerNel Biomedical) by the assessor, who will remain unaware of the intervention.
Blinding of the participant: due to the physiological mechanism of the device (intermittent negative pressure increasing with resistance to airflow), it is assumed that the use of the device in the placebo condition will be sub-therapeutic. To achieve this, the device will be set to a low power for all participants, and a deliberate leak will be incorporated into the output circuit (invisible to the participant) to ensure that the maximum pressure achieved is below the effective minimum negative pressure (-10 cm H2O). The validity of this placebo condition will be confirmed in advance through bench tests. The remaining modalities will mirror those of the active intermittent intrapulmonary deflation session.
Blinding of the statistician: statistical analyses plan will be defined a priori. Statistical analysis will be conducted by an independent statistician who will be unaware of the randomization sequence.
Sample size calculation for a superiority study based on the primary outcome (sensory dimension of dyspnea assessed using the multidimensional dyspea profile questionnaire): to detect a mean difference of at least 2 points between interventions (corresponding to the established minimal clinically important difference for the primary outcome), and considering a moderate effect size of 0.5, a type I error rate of 5%, and a power of 80%, a total of 33 participants will be required. Accounting for a 15% loss to follow-up, up to 40 participants may be included (20 in each crossover group) to ensure that 33 participants have an available measurement for the primary outcome.
Statistical analysis :
Analysis populations:
Three analysis populations will be involved in this study:
- The full analysis Sst will include all randomized participants with at least one efficacy assessment. For those who do not complete the treatment as planned, the last observation will be used as the final outcome (last observation carried forward).
- The per protocol set will include all randomized participants who completed all visits in accordance with the protocol.
- The adherent population will include all randomized participants who completed at least 70% of the prescribed sessions, which is defined 10 sessions or more.
Description of the population:
Qualitative variables will be described by counts and frequencies. Quantitative variables will be summarized using means, standard deviations, and when justified by the distribution of the variable, medians and quartiles will also be reported.
Analysis of outcomes measured only at the end of exercise (performance during the six-minute walk test, nadir transcutaneous oxygen saturation, etc.):
A mixed linear model will be employed for each outcome. The values obtained during the first 6MWT (at rest before the test when available, and after the test), the order of the tests (first or second test), the sequence order (active first then placebo, or placebo first then active), and the treatment modality (active or placebo) will be included as fixed effects, with the participant included as a random effect.
Analysis of other outcomes:
A mixed linear model will be utilized for each outcome. The values obtained during the first six-minute walk test at rest before the test when available, and after the test, and after exercise), the order of the tests (first or second test), the sequence order (active first then placebo, or placebo first then active), the treatment modality (active or placebo), the time of measurement (baseline or post-exercise), and the interaction between treatment modality and time of measurement will be included as fixed effects, with the participant as a random effect.
Analysis of ancillary study endpoints:
The ancillary study will also focus on the primary endpoint and secondary endpoints measured before and/or after the 6MWT, after randomization. A mixed linear model or a mixed logistic model will be used. In this model, the treatment modality (active or placebo) and values obtained during the first 6MWT at inclusion will be included as fixed effects, with the participant as a random effect for variables collected only at the end of exercise. For values measured before and after exercise, the time of measurement (baseline or post-exercise) and the interaction between treatment modality and time of measurement will also be included as fixed effects.
Note 1: the values obtained during the first 6MWT at inclusion are the values at inclusion for each criterion before and after the 6MWT at inclusion. For example, for the primary endpoint, we will use the values of the sensory dimension of dyspnea at inclusion (at rest before the test, and at the end of the test).
Note 2: Statistical models may take into account the interaction between treatment modality and treatment sequence.
The effect of intermittent intrapulmonary pressure release on the proportion of patients with a desaturation of ≥4% will be studied using the McNemar test.
Presentation of results Data will be reported as mean differences (95% confidence intervals) and interpreted according to the minimal clinically important difference for each criterion (when available in the literature) or based on the clinical expertise of the investigators.
Secondary analysis A dose-response analysis will be conducted. The number of sessions will be considered as the dose and the primary endpoint as the response.
Sensitivity analysis A sensitivity analysis will be conducted to assess the influence of various factors, such as the use of inhaled treatments (all types of bronchodilators and anticholinergics), GOLD stage, the presence or absence of oxygen therapy and/or non-invasive ventilation, participant age, or secretory phenotype (based on a COPD Assessment Test score ≥ 6 from the sum of questions 1 and 2, or the Saint George's Respiratory Questionnaire score).
Analyses will be performed using GraphPad Prism 8 and R software.
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 2
- Model description
- Single-center, randomized controlled, prospective, two-arm crossover trial with concealed allocation and double-blinding (participants and evaluators). This study will be accompanied by a pre-planned ancillary study designed to evaluate the acute effects of using the intermittent intrapulmonary deflation device on the same outcomes, based on the initial randomization sequence at the first visit (see Study Description section). Consequently, this ancillary study is a single-center, randomized controlled, prospective, parallel trial with concealed allocation and double blinding (participants and evaluators).
| Arm | Type | Receives |
|---|---|---|
| Active intermittent intrapulmonary deflation | Experimental | Device: Active intermittent intrapulmonary deflation.One week home-based treatment period. |
| Placebo intermittent intrapulmonary deflation | Placebo comparator | Device: Placebo intermittent intrapulmonary deflation.One week home-based treatment period. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (26 listed)
- Age > 18 years;
- COPD stage GOLD II to IV;
- Had completed a pulmonary rehabilitation programme at the investigational site;
- 6-minute walk test < 350 meters before and/or after completing the pulmonary; rehabilitation program;
- mMRC dyspnea scale ≥ 2;
Key exclusion criteria (3 listed)
- Withdrawal of consent;
- Acute COPD exacerbation between visits or onset of cardiorespiratory instability;
- Use of an electrical mechanical device for airway clearance during the study period (in-exsufflator, high-frequency chest oscillation, etc.).
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Active intermittent intrapulmonary deflation.Intermittent intrapulmonary deflation sessions will be performed using the SIMEOX device (SIMEOX, PhysioAssist, Aix-en-Provence, France), which will be delivered to the patient's home by a home healthcare provider. The device power setting (25%, 50%, 75%, or 100%) will be individualized according to the parameters determined during the familiarization visit by a trained physiotherapist. Patients will be instructed to perform tidal volume inspirations followed by passive expirations into the device through a mouthpiece, up to their maximal tolerance. The device will be activated by the patient during expiration using a manual remote control. Each device usage cycle consists of 10 expirations, with oscillations generated at 12 Hz during the first 8 cycles and at 6 Hz during the last 2 cycles. Rest periods will be allowed during the session, and a mandatory pause will be imposed every 10 expirations. The session duration is fixed at 20 minutes, with patients performing one session in the | Device | Active intermittent intrapulmonary deflation |
| Placebo intermittent intrapulmonary deflation.Placebo intermittent intrapulmonary deflation sessions will be performed using the SIMEOX device (SIMEOX, PhysioAssist, Aix-en-Provence, France), which will be delivered to the patient's home by a home healthcare provider. Due to the physiological mechanism of action of the device (intermittent negative pressure with increasing intensity, inversely proportional to airflow resistance), it is assumed that device use under placebo conditions will be infra-therapeutic. To ensure this, the device will be set to the same setting as the active intermittent intrapulmonary deflation session but an intentional air leak will be introduced into the circuit at the device's output (not visible to the participant) to prevent the generated negative pressure from exceeding t The validity of this placebo condition will be confirmed through bench tests. All other conditions will remain identical to the active intermittent intrapulmonary deflation sessions. Patients will be instructed to perform tidal vo | Device | Placebo intermittent intrapulmonary deflation |
Primary outcome
Sensory dimension of dyspnea
Time frame: Day 8 (after seven days of intervention)
The sensory dimension of dyspnea will be assessed using French version of the Multidimensional Dyspnea Profile questionnaire, taking into account the last 30 seconds of effort during the 6-minute walk test to complete the questionnaire. This self-administered questionnaire can yield scores ranging from 0 to 10, with higher scores indicating a greater sensory dimension of dyspnea. The established minimal clinically important difference for this outcome is 2 points.
63 secondary outcomes
Functional exercise capacity - Six-minute walk test
Time frame: Day 8 (after seven days of intervention).
Affective dimension of dyspnea
Time frame: Day 8 (after seven days of intervention).
Intensity of dyspnea
Time frame: Day 8 (after seven days of intervention).
Intensity of lower limb fatigue
Time frame: Day 8 (after seven days of intervention).
Respiratory function - Forced expiratory volume in 1 second
Time frame: Day 8 (after seven days of intervention).
Respiratory function - Vital capacity
Time frame: Day 8 (after seven days of intervention).
Respiratory function - Forced vital capacity
Time frame: Day 8 (after seven days of intervention).
Respiratory function - Ratio between forced expiratory volume in 1 second to forced vital capacity
Time frame: Day 8 (after seven days of intervention).
Respiratory function - Functional residual capacity
Time frame: Day 8 (after seven days of intervention).
Respiratory function - Total lung capacity
Time frame: Day 8 (after seven days of intervention).
Respiratory function - Residual volume
Time frame: Day 8 (after seven days of intervention).
Respiratory function - Airway resistance
Time frame: Day 8 (after seven days of intervention).
Breathing pattern - Tidal volume
Time frame: Day 8 (after seven days of intervention).
Breathing pattern - Respiratory rate
Time frame: Day 8 (after seven days of intervention).
Breathing pattern - Inspiratory time
Time frame: Day 8 (after seven days of intervention).
Breathing pattern - Expiratory time
Time frame: Day 8 (after seven days of intervention).
Breathing pattern - Ratio between inspiratory time to expiratory time
Time frame: Day 8 (after seven days of intervention).
Breathing pattern - Minute ventilation
Time frame: Day 8 (after seven days of intervention).
Operational lung volume - Inspiratory capacity
Time frame: Day 8 (after seven days of intervention).
Operational lung volume - End inspiratory lung volume
Time frame: Day 8 (after seven days of intervention).
Operational lung volume - End expiratory lung volume
Time frame: Day 8 (after seven days of intervention).
Critical inspiratory constraints - Ratio between tidal volume to inspiratory capacity
Time frame: Day 8 (after seven days of intervention).
Critical inspiratory constraints - Ratio between tidal volume to vital capacity
Time frame: Day 8 (after seven days of intervention).
Critical inspiratory constraints - Inspiratory reserve volume
Time frame: Day 8 (after seven days of intervention).
Critical inspiratory constraints - Ratio between inspiratory reserve volume to total lung capacity
Time frame: Day 8 (after seven days of intervention).
Transcutaneous oxygen saturation during a six-minute walk test
Time frame: Day 8 (after seven days of intervention).
Heart rate during the six-minute walk test
Time frame: Day 8 (after seven days of intervention).
Patient satisfaction
Time frame: Day 8 (after seven days of intervention).
Health status
Time frame: Day 8 (after seven days of intervention).
Health related quality of life
Time frame: Day 8 (after seven days of intervention).
Use of the intermittent intrapulmonary deflation device
Time frame: Day 8 (after seven days of intervention).
Adverse events
Time frame: Day 8 (after seven days of intervention).
Weight of secretions
Time frame: During visit 1 (day 1).
Volume of secretions
Time frame: During visit 1 (day 1).
Sensory dimension of dyspnea
Time frame: During visit 1 (day 1).
Affective dimension of dyspnea
Time frame: During visit 1 (day 1).
Functional exercise capacity - Six-minute walk test
Time frame: During visit 1 (day 1).
Intensity of dyspnea
Time frame: During visit 1 (day 1).
Intensity of lower limb fatigue
Time frame: During visit 1 (day 1).
Respiratory function - Forced expiratory volume in 1 second
Time frame: During visit 1 (day 1).
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Jun 2026.
- Background: PubMed 32512047Ekstrom MP, Bornefalk H, Skold CM, Janson C, Blomberg A, Bornefalk-Hermansson A, Igelstrom H, Sandberg J, Sundh J. Minimal Clinically Important Differences and Feasibility of Dyspnea-12 and the Multidimensional Dyspnea Profile in Cardiorespiratory Disease. J Pain Symptom Manage. 2020 Nov;60(5):968-975.e1. doi: 10.1016/j.jpainsymman.2020.05.028. Epub 2020 Jun 6.
- Individual participant dataSharing planned: Yes. Data will be made available upon reasonable request for research purposes after publication. This includes de-identified data related to demographic characteristics, as well as endpoints published either in the main manuscript or any supplemental data. Requests should be sent to Dr T. Bonnevie (t.bonnevie@adir-hautenormandie.com).
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Tristan Bonnevie, PhD principal investigator
Association ADIR
Francis-Edouard Gravier, PhD study chair
ADIR Association
Antoine Cuvelier, Professor study chair
ADIR Association
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Active intermittent intrapulmonary deflation. in people with Chronic Obstructive Pulmonary Disease (COPD), run by ADIR Association at 1 site in France.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 26 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 2 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Tristan Bonnevie, PhD (0235592970 ext. +33, t.bonnevie@adir-hautenormandie.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Sensory dimension of dyspnea (time frame: Day 8 (after seven days of intervention)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06956742, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Jun 2026.