Estimation of respiratory flow by means of normal lung sound.
The respiratory flow is a good indicator of sleep-related breathing disorders. Common praxis is to use a pneumotachograph as the golden standard for flow measurement. However, it does not have to be necessarily the best possible test device for long-term condition, because the device is very uncomfortable and rarely suitable for measurement during sleep. A computer-based method to determine the respiratory flow, called ThorAKUSTIK, yielded a highly positive correlation between the calculated flow out of the tracheal breath sound and a measured flow signal. In order to avoid noise interference due to a breath-mask or a pneumotachograph, in this study we applied the ThorAKUSTIK-method to lung sound which was measured at the back of 18 subjects and investigated the correlation between the calculated flow and the measured flow by a pneumotachograph. The new method showed a highly positive correlation (r = 0.89 and 0.90). Additionally we examined the use of an accelerometer signal to distinguish between inspiration and expiration. In this case we got high correlation coefficients of r = 0.87 and 0.88 between the calculated and measured airflow as well.
Technische Hochschule Mittelhessen - University of Applied Sciences, Giessen, Germany.
Florian
F
Schudt
Technische Hochschule Mittelhessen - University of Applied Sciences, Giessen, Germany.
Volker
V
Gross
ThoraTech GmbH, Giessen, Germany.
Andreas
A
Weissflog
Technische Hochschule Mittelhessen - University of Applied Sciences, Giessen, Germany.
Ljudmila
L
Mursina
Philipps University Marburg, Marburg, Germany.
Ulrich
U
Koehler
Technische Hochschule Mittelhessen - University of Applied Sciences, Giessen, Germany.
Keywan
K
Sohrabi
D000328:Adult; D000465:Algorithms; D001314:Auscultation / Q000379:methods*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012129:Respiratory Function Tests / Q000379:methods; D015656:Respiratory Mechanics / Q000502:physiology*; D012135:Respiratory Sounds / Q000502:physiology*; D012680:Sensitivity and Specificity; D013018:Sound Spectrography / Q000379:methods*; D055815:Young Adult