title: Left and right lung asynchrony as a physiological indicator for unilateral bronchial obstruction in interventional bronchoscopy.
abstract: BACKGROUND
  In patients with bronchial obstruction, pulmonary function tests may not change significantly after intervention. The airflow asynchrony in both lungs due to unilateral bronchial obstruction may be applicable as a physiological indicator. The airflow asynchrony is reflected by the difference in the left and right lung sound development at tidal breathing.
  
  
  OBJECTIVE
  To investigate the usefulness of left and right lung asynchrony due to unilateral bronchial obstruction as a physiological indicator for interventional bronchoscopy.
  
  
  METHODS
  Fifty cases with central airway obstruction were classified into three groups: tracheal, bronchial and extensive obstruction. The gap index was defined as the absolute value of the average of gaps between the left and right lung sound intensity peaks for a 12-second duration.
  
  
  RESULTS
  Before interventional bronchoscopy, the gap index was significantly higher in the bronchial (p<0.05) and extensive obstruction groups (p<0.05) than in the tracheal group. The gap index in cases with unilateral bronchial obstruction of at least 80% (0.18±0.04 seconds) was significantly higher than in cases with less than 80% obstruction (0.02±0.01 seconds, p<0.05). After intervention for bronchial obstruction, the dyspnea scale (p<0.001) and gap index significantly improved (p<0.05), although no significant improvements were found in spirometric assessments. The responder rates for dyspnea were 79.3% for gap indexes over 0.06 seconds and 55.6% for gap indexes of 0.06 seconds or under.
  
  
  CONCLUSIONS
  Assessment of left and right lung asynchrony in central airway obstruction with bronchial involvement may provide useful physiological information for interventional bronchoscopy.
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan.
authors.forename: Masamichi
authors.initials: M
authors.lastname: Mineshita
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Kida
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Nishine
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Handa
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Inoue
authors.affiliation: Division of Respiratory and Infectious Diseases, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan.
authors.forename: Teruomi
authors.initials: T
authors.lastname: Miyazawa
mesh_terms: D000328:Adult; D000368:Aged; D000402:Airway Obstruction / Q000503:physiopathology*; D001982:Bronchial Diseases / Q000503:physiopathology*; D001999:Bronchoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D014132:Trachea / Q000503:physiopathology