title: Intelligent methods for identifying respiratory cycle phases from tracheal sound signal during sleep.
abstract: We present two methods for identifying respiratory cycle phases from tracheal sound signal during sleep. The methods utilize the Hilbert transform in envelope extraction. They determine automatically a patient-specific amplitude threshold to be used in the detection. The core of one method is designed to be amplitude-independent whereas the other method uses solely the amplitude information. The methods provided average sensitivities of 98% and 99%, respectively, and positive prediction values of 100% on the total of 1434 respiratory cycles analysed from six different patients. The developed methods seem promising as such or as tools for analysing sleep disordered breathing.
authors.affiliation: Department of Clinical Neurophysiology, Medical Imaging Centre, Pirkanmaa Hospital District, Tampere, Finland. antti.kulkas@pshp.fi
authors.forename: A
authors.initials: A
authors.lastname: Kulkas
authors.forename: E
authors.initials: E
authors.lastname: Huupponen
authors.forename: J
authors.initials: J
authors.lastname: Virkkala
authors.forename: M
authors.initials: M
authors.lastname: Tenhunen
authors.forename: A
authors.initials: A
authors.lastname: Saastamoinen
authors.forename: E
authors.initials: E
authors.lastname: Rauhala
authors.forename: S-L
authors.initials: SL
authors.lastname: Himanen
mesh_terms: D006801:Humans; D012143:Respiratory Physiological Phenomena; D012890:Sleep / Q000502:physiology*; D014132:Trachea / Q000502:physiology*