title: Computerised acoustical respiratory phase detection without airflow measurement.
abstract: A simple, non-invasive acoustical method is developed to detect respiratory phases in relationship to swallows without the direct measurement of airflow. In 21 healthy subjects (4-51 years) breath sounds are recorded at the trachea and at five different recording locations at the chest wall, with simultaneous recording of airflow by a pneumotachograph. The chest signal with the greatest inspiratory-expiratory power difference ('best location') is either in the mid-clavicular line in the second interspace on the left or third interspace on the right. Using the 'best location' on the chest wall and the tracheal signal, a phase detection algorithm is developed and achieves 100% accuracy in the estimation of respiratory phases without using the measured airflow signal. Thus, acoustically monitoring breaths and swallows holds promise as a non-invasive and reliable assessment tool in the study of swallowing dysfunction.
authors.affiliation: Department of Electrical Engineering, University of Manitoba, Winnipeg, Canada.
authors.forename: Z K
authors.initials: ZK
authors.lastname: Moussavi
authors.forename: M T
authors.initials: MT
authors.lastname: Leopando
authors.forename: H
authors.initials: H
authors.lastname: Pasterkamp
authors.forename: G
authors.initials: G
authors.lastname: Rempel
mesh_terms: D000293:Adolescent; D000328:Adult; D000465:Algorithms; D002648:Child; D002675:Child, Preschool; D003679:Deglutition / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012119:Respiration; D012135:Respiratory Sounds / Q000502:physiology*; D013909:Thorax; D014132:Trachea