title: [Differential diagnosis of stenoses of the large airways by means of lung function tests (author's transl)].
abstract: The different pathophysiological mechanisms involved in producing airflow obstruction at different sites in the tracheobronchial tree enable their differentiation by means of pulmonary function tests. These tests include volume-time measurements at forced in- and expiration, flow-volume measurements forced in- and expiration and flow-pressure measurements in the bodyplethysmograph during quiet breathing. In 23 patients with localized stenosis of the central tracheobronchial tree (12 with extra-thoracic tracheal stenosis, 4 with intrathoracic tracheal stenosis and 7 with main bronchus stenosis) the following parameters proved to be of diagnostic value: In the differential diagnosis of intra-extra-thoracic tracheal stenosis the forced in-expiratory flow-volume curve, in main bronchus stenosis the plethysmographically obtained flow-pressure curve with a large phase lag at zero flow ("trapped air"). In extreme cases the qualitative analysis of the spirogram in connection with the static lung volumes can be diagnostic.
mesh_terms: D000402:Airway Obstruction / Q000175:diagnosis*; D001982:Bronchial Diseases / Q000175:diagnosis; D003251:Constriction, Pathologic; D003937:Diagnosis, Differential; D005541:Forced Expiratory Volume; D006801:Humans; D010993:Plethysmography, Whole Body; D012129:Respiratory Function Tests / Q000379:methods*; D014135:Tracheal Stenosis / Q000175:diagnosis
vernacular_title: Lungenfunktionsanalytische Differenzierung von Stenosen im Bereich der grossen Atemwege.