title: Relationship between computerized wheeze detection and lung function parameters in young infants.
abstract: OBJECTIVE
  Computerized respiratory sound analysis (CORSA) has been validated in the assessment of wheeze in infants, but it is unknown whether automatically detected wheeze is associated with impaired lung function. This study investigated the relationship between wheeze detection and conventional lung function testing (LFT) parameters.
  
  
  METHODS
  CORSA was performed using the PulmoTrack® monitor in 110 infants, of median (interquartile range) postmenstrual age 50 (46-56) weeks and median body weight 4,810 (3,980-5,900) g, recovering from neonatal intensive care. In the same session, LFT was performed, including tidal breathing measurements, occlusion tests, body plethysmography, forced expiratory flow by rapid thoracoabdominal compression, sulfur hexafluoride (SF6 ) multiple breath washout (MBW), and capillary blood gas analysis. Infants were classified as wheezers or non-wheezers using predefined cut-off values for the duration of inspiratory and expiratory wheeze.
  
  
  RESULTS
  Wheezing was detected in 72 (65%) infants, with 43 (39%) having inspiratory and 53 (48%) having expiratory wheezing. Endotracheal mechanical ventilation in the neonatal period for > 24 hr was associated with inspiratory wheeze (P = 0.009). Airway resistance was increased in both inspiratory (P = 0.02) and expiratory (P = 0.004) wheezers and correlated with the duration of expiratory wheeze (r = 0.394, P < 0.001). Expiratory wheezers showed a significant increase in respiratory resistance (P = 0.001), time constant (0.012), and functional residual capacity using SF6 MBW (P = 0.019). There was no association between wheezing and forced expiratory flow or blood gases.
  
  
  CONCLUSIONS
  CORSA can help identify neonates and young infants with subclinical airway obstruction and may prove useful in the follow-up of high-risk infants.
authors.affiliation: Department of Neonatology, Charité University Medical Center, Berlin, Germany.
authors.forename: Hendrik Stefan
authors.initials: HS
authors.lastname: Fischer
authors.affiliation: Department of Neonatology, Charité University Medical Center, Berlin, Germany.
authors.forename: Lia Carlotta
authors.initials: LC
authors.lastname: Puder
authors.affiliation: Department of Neonatology, Charité University Medical Center, Berlin, Germany.
authors.forename: Silke
authors.initials: S
authors.lastname: Wilitzki
authors.affiliation: Department of Pediatric Pneumology and Immunology, Charité University Medical Center, Berlin, Germany.|Department of Pediatric Pneumology, University Children's Hospital, Basel, Switzerland.
authors.forename: Jakob
authors.initials: J
authors.lastname: Usemann
authors.affiliation: Department of Neonatology, Charité University Medical Center, Berlin, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Bührer
authors.affiliation: Emeritus Professor of Pediatrics, Hadassah-Hebrew University, Jerusalem, Israel.
authors.forename: Simon
authors.initials: S
authors.lastname: Godfrey
authors.affiliation: Department of Neonatology, Charité University Medical Center, Berlin, Germany.
authors.forename: Gerd
authors.initials: G
authors.lastname: Schmalisch
mesh_terms: D000402:Airway Obstruction / Q000175:diagnosis* / Q000503:physiopathology; D000403:Airway Resistance; D003936:Diagnosis, Computer-Assisted; D005260:Female; D005652:Functional Residual Capacity; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008168:Lung / Q000503:physiopathology*; D008297:Male; D010993:Plethysmography, Whole Body; D012121:Respiration, Artificial; D012129:Respiratory Function Tests; D012135:Respiratory Sounds / Q000175:diagnosis* / Q000503:physiopathology; D012680:Sensitivity and Specificity
keywords: auscultation; computerized wheeze detection; infant; lung function; lung sound; phonopneumography; wheezing