The Effects of a Positive Expiratory Pressure (PEP) on Dyspnea and Dynamic Hyperinflation During Exercise in Chronic Obstructive Pulmonary Disease (COPD) Patients

Study Overview
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Brief Summary
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From the relationship between pathophysiology of chronic obstructive pulmonary disease (COPD), dyspnea, and dynamic hyperinflation during ventilatory increasing, the investigators hypothesize that Positive expiratory pressure (PEP) breathing will reduce dyspnea more than normal breathing during exercise in mild to moderate COPD patients. PEP breathing will improve dynamic hyperinflation during exercise more than normal breathing in mild to moderate COPD patients. PEP breathing will improve cardiorespiratory function during exercise than normal breathing in mild to moderate COPD patients.

Detailed Description
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Expiratory airflow limitation is the pathophysiological hallmark of chronic obstructive pulmonary disease (COPD) that leads to air trapping and increases in dynamic hyperinflation (DH) and consequently causes dyspnea during exercise. Although pursed lips breathing is a simple technique that provides a positive back pressure may retard the airway collapsed, but previous studies showed an unsuccessful reduction of DH which might cause by insufficient back pressure. And thereby a conical positive expiratory pressure (C-PEP) has been developed in our laboratory to generate back pressure higher than pursed lips breathing. Moreover, an effect of PEP on DH has not carried out in patient with COPD. Therefore, the objective of the present study was to examine effects of a C-PEP on DH and respiratory response during exercise in patient with COPD.

Official Title
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The Effects of a Positive Expiratory Pressure (PEP) on Dyspnea and Dynamic Hyperinflation During Exercise in COPD Patients

Conditions
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Chronic Obstructive Pulmonary Disease

Intervention / Treatment
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* Device: Conical Positive Expiratory Pressure Device (C-PEP)
* Other: Control breathing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with stable mild-to-moderate COPD (Both stages: FEV1/FVC < 70%. Mild stage: FEV1 ≥ 80% predicted; Moderate stage: 50% ≤ FEV1 < 80% predicted according to Global Initiative Obstructive Lung Disease (GOLD) guideline). Free of exacerbations for more than 4 weeks (as defined by a change to pharmacological therapy, admission to hospital or ER or unscheduled clinic visit). Good communication Exclusion Criteria: Older than 70 years old Musculoskeletal problems that limit mobility Cardiovascular disease Neurological or psychiatric illness Patient on long term oxygen or domiciliary noninvasive positive pressure ventilation Any other comorbidities which would affect ability to undertake exercise test

Ages Eligible for Study
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Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: I<br>Patients breath while a conical positive expiratory pressure device during exercises | Device: Conical Positive Expiratory Pressure Device (C-PEP)<br>* Conical positive expiratory pressure device (C-PEP) in this study was designed on the principle of expiratory flow retardation. The principle occurs when exhaling through a small tube diameter, i.e. a small straw, pursed lip breathing, or positive expiratory pressure. Expiratory retardation, results from a decrease in tube diameter, creates flow resistance during exhalation. With flow resistance, the greater the flow the greater the back pressure, and the less the flow the lower the pressure. Expiratory retardation was applied in an attempt to facilitate exhalation and to relieve the air trapping. The optimal design was found to be: cone shape, proximal diameter is 2.0 cm, distal diameter is 0.6 cm, and length is 2.5 cm. Subjects will rest for 10-15 minutes until HR, BP are stabilized. They will undertake 15 min of alternating quadriceps exercise (30% 1 RM) either breathing with the C-PEP device.<br>|
| Active Comparator: C<br>Patients (normal) breath during exercise | Other: Control breathing<br>* Subjects will rest for 10-15 minutes until HR, BP are stabilized. They will undertake 15 min of alternating quadriceps exercise (30% 1 RM) either breathing normally.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inspiratory Capacity |  | at 0th, 5th,  20th minutes of exercises | 
| Borg scale |  | at 0th and 20th minutes of exercises | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart Rate |  | every minutes of exercise and recovery periods | 
| Exercise time |  | at the times when participants stop exercises | 
| Recovery time |  | the periods between end of symptomatic limited constance workload exercises to full recovery heart rate | 
| Respiratory rate |  | every minutes of exercise and recovery periods | 
| Inspiratory time |  | every minutes of exercise and recovery periods | 
| Expiratory time |  | every minutes of exercise and recovery periods | 
| Sp02 |  | every minutes of exercise and recovery periods | 
| PetCO2 |  | every minutes of exercise and recovery periods | 
| Mouth pressure |  | every minutes of exercise periods | 
| Flow rate |  | every minutes of exercise periods | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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chronic obstructive pulmonary disease, dynamic hyperinflation, dyspnea, recovery, positive expiratory pressure, exercise