Dynamic Carbon Dioxide (CO2) Administration for Sleep Apnoea
Recruitment status was Not yet recruiting
Normally breathing is controlled by a reflex that responds to the levels of carbon dioxide (CO2) in the blood. In heart failure, where the heart muscle is damaged and therefore does not pump as well, this reflex is exaggerated. The result is a vicious circle: blood CO2 levels fluctuate wildly and as a result breathing also fluctuates with patients hyperventilating at times and briefly stopping breathing at others. During sleep this is called central sleep apnoea (CSA).
Patients with CSA wake up throughout the night and whilst some patients are oblivious to this, others are consciously breathless and many patients are tired during the day and feel unable to perform their daily activities.
As part of the body's stress response to the erratic pattern of breathing, both blood pressure and heart rate may rise to a level that is harmful in a failing heart, exacerbating the underlying heart failure. Indeed patients who demonstrate this CSA die sooner than those who have heart failure and stable breathing.
There are no proven specific therapies for CSA that stabilise breathing, improve sleep quality, and prolong life. We have designed a system which delivers very small doses of CO2, when the blood level of CO2 is predicted to be low. During short daytime recordings, using this system, we have demonstrated that it is possible to stabilise the body's CO2 levels.
We aim to test what happens when CO2 is given overnight whilst the patient is sleeping to see whether we can stabilise their breathing over longer durations and whether sleep quality could be improved so that patients are less tired during the day. In addition, we would like to measure whether the stress response is lessened if the breathing is successfully stabilised.
|Study Design:||Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Single Blind (Subject)
Primary Purpose: Treatment
|Official Title:||Dynamic Carbon Dioxide Administration for Central Sleep Apnoea in Heart Failure|
- Extent of respiratory instability [ Time Frame: over 8 hours ] [ Designated as safety issue: No ]
- Arousals [ Time Frame: over 8 hours ] [ Designated as safety issue: No ]
- End-tidal CO2 [ Time Frame: per breath ] [ Designated as safety issue: No ]
- 24 hour urinary catecholamines [ Time Frame: per 24 hours ] [ Designated as safety issue: No ]
- Mean heart rate [ Time Frame: per 1 s ] [ Designated as safety issue: No ]
- Number of ectopic heart beats [ Time Frame: per 8 hours ] [ Designated as safety issue: No ]
- Mean blood pressure [ Time Frame: every 9 hours ] [ Designated as safety issue: No ]
- Mean Ventilation [ Time Frame: every 1 second ] [ Designated as safety issue: No ]
|Study Start Date:||February 2010|
|Estimated Study Completion Date:||October 2010|
|Estimated Primary Completion Date:||October 2010 (Final data collection date for primary outcome measure)|
Other: Carbon dioxide
|Foundation G. Monasterio|
|Pisa, Italy, 56124|
|Imperial NHS Trust|
|London, United Kingdom, W21NY|
|Principal Investigator:||Darrel P Francis, MD||Imperial College London|