Effect of Short-term Oxygen During CPET in ILD

Study Overview
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Brief Summary
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In a randomized, sham-controlled crossover trial the investigators will test whether supplemental oxygen given during cardiopulmonary exercise testing will improve exercise performance and physiological parameters in patients with interstitial lung disease.

Official Title
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Effect of Short-term Ambulatory Oxygen Therapy on Cardiopulmonary Exercise Capacity in Patients With Interstitial Lung Disease (ILD)

Conditions
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Interstitial Lung Disease

Intervention / Treatment
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* Procedure: Incremental exercise test (IET)
* Procedure: Constant work rate exercise test (CWRET)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: interstitial lung disease, diagnosed by high-resolution CT FEV1/FVC >70% and FVC <85% predicted stable medication for at least 4 weeks Desaturation in SpO2 in 6-minute walk test of ≥ 4% to absolute values ≤ 92% Signed Informed Consent Male and female patients 18 to 80 years of age Exclusion Criteria: Severe daytime hypoxemia (PaO2 ≤7.3 or <55 mmHg at rest) Other clinically significant concomitant disease states (e.g., cardiovascular disease, hepatic dysfunction, etc) Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia or confusional state of the subject, neurological or orthopaedic problems with walking disability or inability to ride a bicycle Women who are pregnant or breast feeding

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Oxygen<br>Supplemental oxygen will be applied via a mask during CPET | Procedure: Incremental exercise test (IET)<br>* Incremental cardio pulmonary exercise test until exhaustion<br>Procedure: Constant work rate exercise test (CWRET)<br>* constant (on 75% Wmax) cardio pulmonary exercise test until exhaustion<br>|
| Sham Comparator: Air<br>Sham ambient air will be applied via mask during CPET | Procedure: Incremental exercise test (IET)<br>* Incremental cardio pulmonary exercise test until exhaustion<br>Procedure: Constant work rate exercise test (CWRET)<br>* constant (on 75% Wmax) cardio pulmonary exercise test until exhaustion<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Work Rate (in watts) | Maximal Work Rate (Watt max) measured during incremental exercise tests (IET) in cardiopulmonary exercise tests | 1 day | 
| Endurance time (in seconds) | Endurance (sec) with 75% Wmax measured during constant work rate exercise tests (CWRET) in cardiopulmonary exercise tests | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes in physiological vital signs: Heart rate (hr) | Hr (in beats per minute) | 1 day | 
| changes in physiological vital signs: Blood pressure | Systolic and diastolic blood pressure (in mmHg) | 1 day | 
| Changes in breathing patterns: Minute ventilation (VE) | VE (in liters per minute) | 1 day | 
| Changes breathing patterns: Tidal volume (Vt) | Vt (in liters) | 1 day | 
| Changes in breathing patterns: Oxygen uptake (VO2) | VO2 (in liters per minute) | 1 day | 
| Changes in breathing patterns: Carbon dioxide output (VCO2) | VCO2 (in liters per minute) | 1 day | 
| Changes in breathing patterns: Breathing equivalent for O2 (VE/VO2) | ratio between minute ventilation and oxygen uptake | 1 day | 
| Changes in breathing patterns: Breathing equivalent for O2 (VE/VCO2) | ratio between minute ventilation and carbon dioxide output | 1 day | 
| Changes in breathing patterns: VE/VCO2Slope | Ratio between minute ventilation and carbon dioxide output if carbon dioxide reaches the breathing plateau | 1 day | 
| Changes in breathing patterns: Ventilatory threshold one (Vt1) | represents the start of anaerobic metabolism | 1 day | 
| Changes in breathing patterns: Ventilatory threshold two (Vt2) | represents the start of higher percentage of the anaerobic metabolism | 1 day | 
| Changes in arterial blood: arterial partial pressure of O2 (PaO2) | PaO2 (in kPa) | 1 day | 
| Changes in arterial blood: arterial partial pressure of CO2 (PaCO2) | PaCO2 (in kPa) | 1 day | 
| Changes in arterial blood: arterial lactate concentration | lactate concentration (in mmol per liter) | 1 day | 
| Changes in arterial blood: pondus Hydrogenii (pH) values | pH (1-14) | 1 day | 
| Changes in arterial blood: Bicarbonate (HCO3) | HCO3 (in mmol per liter) | 1 day | 
| Changes in tissue oxygenation: Pulse oxymetrie (SpO2, measured at the finger) | SpO2 (in percent) | 1 day | 
| Changes in tissue oxygenation: Cerebral tissue oxygenation (CTO, measured at the forehead) | CTO (in percent) | 1 day | 
| Changes in tissue oxygenation: Muscle tissue oxygenation (MTO, measured at the quadriceps muscle) | MTO (in percent) | 1 day |