A Clinical Trial on Effectiveness and Safety of Hydrogen Generator to Treat Dyspnea for the Patients With Tracheal Stenosis: A Randomized, Double-blind and Single-center Clinical Study

Study Overview
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Brief Summary
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Investigators aim to study the effectiveness and safety of inhaling hydrogen-oxygen which produced by a hydrogen generator with nebulizer to decreases inspiratory effort for the patients with tracheal stenosis.

Official Title
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A Clinical Trial on Effectiveness and Safety of Inhaling Hydrogen-oxygen to Decreases Inspiratory Effort for the Patients With Tracheal Stenosis: A Randomized, Double-blind and Single-center Clinical Study

Conditions
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Tracheal Stenosis

Intervention / Treatment
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* Device: Hydrogen generator treatment
* Device: Oxygen-making machine treatment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged from 18 to 65; Diagnosed moderate/severe tracheal stenosis by chest CT and/or bronchoscopy; Difficulty breathing symptoms Agree to participate in this trial and sign the informed consent form. Exclusion Criteria: Those who were suffered from respiratory failure or more severe caused by dyspnea; Combined other serious systemic diseases (severe arrhythmia, acute myocardial ischemia, uncontrollable hypertension crisis, active gastric ulcer, uncontrolled diabetes, renal failure, blood system diseases or coagulation dysfunction); Those who were suffered from severe mental illness or could not take care of themselves; Pregnant or lactating women; Those who could not understand the trial procedures and correctly the trial equipment; Those who participated in other clinical trials in the first 3 months before the screening date. Quit criteria The subjects requiring emergency intubation or other intervention or surgical treatment due to worsened tracheal stenosis; Subjects who had severe adverse events during treatment; Subjects who did not want to continue to participate in the trial; The subjects who were necessarily terminated for the trial by the investigators.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Hydrogen generator treatment<br>Inhalation of hydrogen-oxygen mixed gas. | Device: Hydrogen generator treatment<br>* The patients mainly used the hydrogen generator with nebulizer for inhalation of hydrogen-oxygen mixed gas.<br>Device: Oxygen-making machine treatment<br>* The patients mainly used medical molecular sieve oxygen-making machine for oxygen inhalation.<br>|
| Sham Comparator: Oxygen-making machine treatment<br>Inhalation of oxygen. | Device: Hydrogen generator treatment<br>* The patients mainly used the hydrogen generator with nebulizer for inhalation of hydrogen-oxygen mixed gas.<br>Device: Oxygen-making machine treatment<br>* The patients mainly used medical molecular sieve oxygen-making machine for oxygen inhalation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in sRMSdi/para/sc, RMSdi, Pdi& MIP from baseline after inhalation by bench study. | sRMSdi/para/sc: root-mean-square of diaphragm/parasternal/sternocleidomastoid surface electromyography; RMSdi: root-mean-square of diaphragm electromyography; Pdi: Transdiaphragmatic pressure; MIP:maximal inspiratory pressure. | Baseline, 10min, 20min, 30min, 40min, 50min, 90min and 150min | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Borg score for dyspnea after inhalation. |  | Baseline, 10min, 20min, 30min, 40min, 50min, 90min and 150min | 
| Change in symptom of dyspnea from baseline after inhalation. | Changes in comfort with each gas mixture were evaluated by a simple questionnaire | Baseline, 10min, 20min, 30min, 40min, 50min, 90min and 150min | 
| Change in signs(BR, HR, BP, el) from baseline after inhalation | Change in signs include breath rate， heart rate， blood pressure，Three Depression Sign and so on. | Baseline, 10min, 20min, 30min, 40min, 50min, 90min and 150min | 
| Change in PaO2, PaCO2, PH& HCO3- after inhalation | Change in Arterial blood gases. | Baseline and 150min | 
| FEV1 & FVC | Forced expiratory volume in one second & Forced vital capacity. | Baseline | 
| Change in impulse oscillometry variables(R5,R20,X5,AX,RF) as change from baseline when inhaling. | R5 - Resistance at 5Hz, R20 - Resistance at 20Hz, X5 - Reactance at 5Hz, RF - Frequency of resonance, AX - Area under reactance curve | Baseline and inhaling | 
| Change in cough waves from baseline when inhaling | Cough waves will be recorded by a voice recorder. | Baseline, Inhaling. | 
| Grades of airway stenosis by bronchoscopy |  | baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Tracheal stenosis, Hydrogen generator, Hydrogen-oxygen, Dyspnea.