title: In vivo measurement of lung capillary-alveolar macromolecule permeability by saturation bronchoalveolar lavage.
abstract: OBJECTIVE
  Measurement of capillary-alveolar permeability to fluorescein isothiocyanate-dextran (FITC-D) (molecular mass, 71,300 daltons) by a sequential bronchoalveolar lavage (BAL) technique.
  
  
  METHODS
  Animal research.
  
  
  METHODS
  The Department of Physiology at a scientific and medical university.
  
  
  METHODS
  Nine anesthetized and mechanically ventilated dogs.
  
  
  METHODS
  Two separate experiments were performed in each subject-an initial control experiment followed by an oleic acid-induced lung injury. The indicator was administered at constant blood concentration before serial BAL including eight fluid instillation-recovery cycles.
  
  
  METHODS
  Plasma to BAL solute clearance at saturation (capillary-alveolar clearance at saturation, mL/min) was calculated and normalized to lavage fluid volume (measured by 1251 serum albumin dilution) to obtain a transport rate (TR) constant.
  
  
  RESULTS
  TR for FITC-D70 was 4.0+/-0.8 and 46.1+/-18.1 x 10(-5) x min(-1) in control and injured lung, respectively (p < .02). Capillary-alveolar clearance of FITC-D70 was not affected by the lavage procedure itself. TR reflected essentially epithelial permeability in normal lung and combined epithelial and endothelial permeability in injured lung. A significant correlation was found between cardiac output and TR in injured lung.
  
  
  CONCLUSIONS
  Saturation BAL allowed us to estimate capillary-alveolar macromolecule permeability in vivo in dogs. Further study may allow bedside evaluation of lung injury by BAL in patients.
authors.affiliation: Unité Mixte de Recherche 5525, Centre National de Recherche Scientifique, Université Joseph Fourier, Grenoble, France.
authors.forename: S
authors.initials: S
authors.lastname: Bayat
authors.forename: D
authors.initials: D
authors.lastname: Anglade
authors.forename: A
authors.initials: A
authors.lastname: Menaouar
authors.forename: J L
authors.initials: JL
authors.lastname: Martiel
authors.forename: J L
authors.initials: JL
authors.lastname: Lafond
authors.forename: G
authors.initials: G
authors.lastname: Benchetrit
authors.forename: F A
authors.initials: FA
authors.lastname: Grimbert
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid; D002199:Capillary Permeability / Q000502:physiology*; D004285:Dogs; D016650:Fluorescein-5-isothiocyanate / Q000493:pharmacokinetics*; D005456:Fluorescent Dyes / Q000493:pharmacokinetics*; D006439:Hemodynamics; D011650:Pulmonary Alveoli / Q000502:physiology*
chemical_list: D005456:Fluorescent Dyes; D016650:Fluorescein-5-isothiocyanate