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Drug-Induced Sleep Endoscopy DISE with Target Controlled Infusion TCI and Bispectral Analysis in Obstructive Sleep Apnea
Published on: December 6, 2016
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Relationship between obstructive sleep apnea and endogenous carbon monoxide.
Masanori Azuma1, Kimihiko Murase1, Ryo Tachikawa1
1Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan; and.
Journal of Applied Physiology (Bethesda, Md. : 1985)
|November 19, 2016
Summary
Exhaled carbon monoxide (CO) levels, but not blood CO, correlate with hypoxia in obstructive sleep apnea (OSA) patients. Continuous positive airway pressure therapy reduces exhaled CO, suggesting it reflects OSA-related oxidative stress.
Area of Science:
- Biochemistry
- Sleep Medicine
- Respiratory Physiology
Background:
- Endogenous carbon monoxide (CO) is a marker of heme oxygenase-1 activity, induced by hypoxia and oxidative stress.
- Few studies have investigated endogenous CO levels in obstructive sleep apnea (OSA) patients.
- The differential impact of OSA on exhaled versus blood CO levels remains unclear.
Purpose of the Study:
- To compare exhaled and blood CO levels in patients with suspected OSA.
- To investigate the correlation of these CO levels with sleep parameters and hypoxia.
- To assess the effect of continuous positive airway pressure (CPAP) therapy on CO levels in OSA patients.
Main Methods:
- Prospective study of 69 patients with suspected OSA.
- Measurement of exhaled and blood CO levels at night and in the morning.
- Correlation analysis with sleep parameters (e.g., apnea-hypopnea index, oxygen saturation).
- Comparison of CO levels between OSA and control groups, and before/after CPAP therapy.
Main Results:
- Exhaled and blood CO levels were significantly correlated.
- Exhaled CO levels correlated with nocturnal hypoxia (arterial oxygen saturation < 90%) and total sleep time, while blood CO did not.
- Exhaled CO levels were significantly higher in OSA patients (AHI ≥ 15) than in controls (AHI < 15).
- CPAP therapy significantly reduced exhaled CO levels in OSA patients, but not blood CO levels.
Conclusions:
- Exhaled CO levels are positively related to hypoxia during sleep in OSA patients.
- Blood CO levels do not correlate with sleep parameters or hypoxia in OSA.
- Exhaled CO may serve as a more sensitive indicator of oxidative stress associated with OSA than blood CO.
- CPAP therapy effectively reduces exhaled CO, supporting its role as a biomarker for OSA-related oxidative stress.
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