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Published on: December 6, 2016
Acoustical flow estimation in patients with obstructive sleep apnea during sleep
Azadeh Yadollahi1, Ali Azarbarzin, Aman Montazeri
1Institute of Biomaterial and Biomedical Engineering, University of Toronto, Canada. azadeh.yadollahi@uhn.ca
Summary
Acoustical flow estimation for breathing is more accurate during sleep when calibrated with sleep data. This method reliably detects upper airway obstructions in obstructive sleep apnea (OSA).
Area of Science:
- Respiratory physiology
- Biomedical engineering
- Sleep medicine
Background:
- Tracheal respiratory sound analysis offers a non-invasive method for studying airway pathophysiology.
- Previous research has explored its use in acoustical flow estimation and sleep apnea diagnosis.
- The accuracy of acoustical flow estimation during sleep, particularly in individuals with obstructive sleep apnea (OSA), remained uninvestigated.
Purpose of the Study:
- To investigate the accuracy of acoustical flow estimation during sleep in individuals with OSA.
- To compare two calibration approaches for acoustical flow estimation models: one using wakefulness data and another using sleep data.
- To assess the reliability of acoustical methods for breathing flow estimation and airway obstruction detection during sleep.
Main Methods:
- Recorded tracheal sounds, airflow rates, and head positions from 11 individuals with OSA during both sleep and wakefulness.
- Evaluated two calibration strategies for the acoustical flow estimation model using recorded data.
- Analyzed the changes in model parameters between wakefulness and sleep states.
Main Results:
- Acoustical flow estimation parameters significantly differ between wakefulness and sleep.
- Models calibrated with wakefulness data show high quantitative flow estimation errors during sleep.
- Models calibrated with sleep data achieve a flow estimation error of less than 5% during sleep.
Conclusions:
- Acoustical flow estimation parameters are state-dependent, changing from wakefulness to sleep.
- Calibration using sleep data is crucial for accurate acoustical flow estimation during sleep.
- Acoustical methods are reliable for estimating breathing flow and detecting upper airway obstructions during sleep in OSA patients.
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