Central Sleep Apnea Treated by CO2 Supplied by a Novel Device

Study Overview
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Brief Summary
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In general, central sleep apnea is not as common as obstructive sleep apnea but it is common in patients with heart failure. It has been repeatedly shown that central sleep apnea worsens the prognosis of heart failure. The current concept in the development of CSA is hypocapnia which causes temporary cessation of respiratory neural output. Different methods for supplement of CO2 have been used to eliminate CSA. However, variation of CO2 concentration during overnight treatment and tight-fitting mask made the treatment uncomfortable. It is important to develop a device with a comfortable mask to supply constant low dose CO2 without breathing difficulty. We recently developed a device for treatment of CSA.

Detailed Description
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Objective: To determine whether the device could improve sleep quality while eliminating CSA during the overnight study. Methods: Patients with central sleep apnea diagnosed by diaphragm EMG will be recruited in this study. CO2 concentration for treatment would be manually titrated during overnight PSG. Patients were then treated with an effective lowest concentration of CO2 derived from titration under PSG on the third night. The sleep apnea hypopnea index (AHI), central sleep apnea index (CHI), arousal index (ArI), Oxygen desaturation index (ODI), sleep structure, blood pressure, heart rate, diaphragm EMG, treatment side effects and treatment preference were to be observed.

Official Title
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Central Sleep Apnea Treated by CO2 Supplied by a Novel Device

Conditions
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Central Sleep Apnea

Intervention / Treatment
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* Device: novel device with a comfortable mask


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Willing to participate after informed consent Males and females, any race and aged≥18yeras Objectively confirmed central sleep apnea/Cheyne Stokes Respiration with an apnoea-hypopnoea- index (AHI)≥5/h by overnight polysomnography Exclusion Criteria: Obstructive sleep apnea Severe COPD，FEV1/FVC<70% and FEV1<60% Chronic CO2 retention with unknown reason Severe nasal congestion Poor understanding

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 82 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
Intervention Model: Sequential Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Treatment with CO2<br>Patients were treated with an effective lowest concentration of CO2 delivered by the novel CO2 supply system. | Device: novel device with a comfortable mask<br>* Using a device with a comfortable mask to supply constant low dose CO2 to treat patients.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Apnea Hypopnea Index | Total number of apneas and hypopneas/total sleep time (h) | One full night | 
| Central sleep apnea index | Total number of central sleep apneas/total sleep time (h) | One full night | 
| Arousal Index | Total number of arousals/total sleep time(h) | One full night | 
| Oxygen Desaturation Index | Total number of oxygen desaturations≥3% /total sleep time(h) | One full night | 
| Sleep structure | Assessment of the sleep efficiency (percentage is calculated by dividing Total Sleep Time by Total Time in bed) | One full night | 
| Sleep structure | Assessment of the sleep stage distribution (percentage calculated by diving the time of stage N1, N2, N3, NREM by total sleep time) | One full night | 
| Adverse effects | Using questionnaire named side effects of feeling to assess adverse effects exiting or not, including dyspnea, noise, bloating, itchy face, dry mouth, ophthalmalgia, stuffy nose, et al. When the side effect events in intervening condition 2 times more than baseline is worse outcome. | One full night | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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CSA