The Effect of Non-invasive Ventilation on the Oxygenation of Peripheral Muscle in Hypercapnic COPD Patients

Study Overview
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Brief Summary
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In this study, 20 hypercapnic COPD patients will perform two constant workrate endurance cycle tests. One test will be while using non-invasive Ventilation (NIV) support, one without in a randomized cross-over design. The aim is to measure, whether NIV is able to change peripheral and respiratory muscle oxygenation.

Detailed Description
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In this study patients will perform one incremental work rate test to obtain peak work rate. On the following days two constant work rate cycle endurance tests (CWRT) will be performed at 60% of Peak work rate using a randomised cross-over design. Between the two CWRTs there will be one hour of recovery time in between. One of the CWRTs will be performed with the support of non-invasive Ventilation (NIV), the other one without. Respiratory and cardiovascular parameters will be observed through transcutaneous measurement of CO2 (Sentec device) and near-infrared spectroscopy devices. The purpose of this study is, to examine whether the use of NIV not only decreases patients dyspnoea, but also has positive effects on the patients cardiovascular System, exercise capacity and muscle oxygenation. The investigators will examine the tissue oxygen saturation in the 7th intercostal space (reflecting a respiratory muscle) and on the M. vastus lateralis of the leg during both CWRTs. With the Support of NIV, it is expected to see a change in the oxygenation towards a better perfusion of the leg muscle, due to a facilitation of the work of breathing. This may result in a later onset of leg fatigue and an increased exercise capacity of the patients. To have an equivalent workload all parameters will be compared during isotime. To conclude, aim of this study is to record the interplay of Oxygenation and Perfusion between the Intercostal muscles and the peripheral leg muscle during exercise. The investigators hypothesize, that the use of NIV may change the oxygenation in favour of the leg muscle through relieving the respiratory muscles.

Official Title
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The Effect of Non-invasive Ventilation on the Oxygenation of Peripheral Muscle Tissue, Cardiovascular System and Exercise Capacity in Hypercapnic COPD Patients

Conditions
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COPD, Hypercapnia

Intervention / Treatment
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* Device: non-invasive ventilation (NIV)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Chronic obstructive pulmonary disease GOLD (Global initiative for chronic obstructive lung disease) stage IV Hypercapnia: pCO2>50mmHg (at rest or in exercise) written consent Exclusion Criteria: orthopaedic comorbidities that do not allow a cycle endurance test acute exacerbation of COPD Cardiac insufficiency, acute coronary syndrome

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 80 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: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: cycling test first with NIV, then without NIV<br>patients in this arm will perform their first constant work rate test while using NIV and the second constant work rate test without NIV | Device: non-invasive ventilation (NIV)<br> <br> |
| Experimental: cycling test first without NIV, then with NIV<br>patients in this arm will perform their first constant work rate test without NIV and the second constant work rate test with NIV | Device: non-invasive ventilation (NIV)<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| cycle endurance time | time patient ist able to cycle at 60% of his peak work rate | maximum 20 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Borg scale of dyspnoea | In the beginning and in the end of the constant work rate tests patients will be asked to rate their current level of dyspnoea on the modified Borg scale from 0 to 10 | 30 minutes | 
| Borg scale of leg fatigue | In the beginning and in the end of the constant work rate tests patients will be asked to rate their current Level of leg fatigue on the modified Borg scale from 0 to 10 | 30 minutes | 
| Oxygen saturation | Measurement of the oxygen saturation during the constant work rate tests | 30 minutes | 
| Heart rate | Measurement of the heart rate during the constant work rate tests using a pulse oximeter | 30 minutes | 
| Arterial blood pressure | Riva-Rocci measurement of the arterial blood pressure before and in the end of the constant work rate tests | 30 minutes | 
| arterial carbondioxide partial pressure | recording of the transcutaneously measured arterial carbondioxide partial pressure using Sentec technology during the constant work rate tests | 30 minutes | 
| Tissue Saturation Index | the near infrared technology delivers the Tissue Saturation Index throughout the constant work rate test | 30 minutes | 
| total hemoglobin | the near infrared technology delivers the Tissue Saturation Index throughout the constant work rate test | 30 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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NIV, COPD, NIRS, Exercise