title: Perfluorocarbon-associated gas exchange in gastric aspiration.
abstract: OBJECTIVE
  To test whether perfluorocarbon-associated gas exchange (gas ventilation of the perfluorocarbon-liquid filled lung) could support oxygenation better than conventional positive pressure breathing in a piglet model of gastric aspiration-induced adult respiratory distress syndrome (ARDS).
  
  
  METHODS
  Prospective, randomized, blinded, controlled study.
  
  
  METHODS
  A critical care research laboratory in a university medical school.
  
  
  METHODS
  Fourteen healthy piglets.
  
  
  METHODS
  Under alpha-chloralose anesthesia and metocurine iodide neuromuscular blockade, 14 piglets underwent tracheostomy; central venous, systemic and pulmonary arterial catheterizations; and volume-regulated continuous positive-pressure breathing. Homogenized gastric aspirate (1 mL/kg) titrated to pH of 1.0 was instilled into the tracheostomy tube of each subject at 0 min to induce ARDS. Hemodynamics, lung mechanics, and gas exchange were evaluated every 30 mins for 6 hrs. Seven piglets were treated at 60 mins by tracheal instillation of perflubron, a volume selected to approximate normal functional residual capacity, and were supported by perfluorocarbon-associated gas exchange without modifying ventilatory settings. Perflubron was added to the trachea every hour to replace evaporative losses.
  
  
  RESULTS
  There was a significant difference in oxygenation over time when tested by repeated-measures analysis of variance (F test = 8.78, p < .01). On further analysis, the differences were not significant from baseline to 2.5 hrs but became increasingly significant from 2.5 to 6 hrs after injury (p < .05) in the inflammatory phase of gastric aspiration-induced ARDS. Histologic evidence for ARDS in the treated group 6 hrs after injury was lacking.
  
  
  CONCLUSIONS
  In the piglet model, perfluorocarbon-associated gas exchange with perflubron facilitates oxygenation in the acute phase of gastric aspiration-induced inflammatory ARDS when compared with conventional positive-pressure breathing. Histologic and physiologic data suggest that perfluorocarbon-associated gas exchange with perflubron might prevent ARDS if instituted after aspiration in the time window before the acute inflammatory process is manifest.
authors.affiliation: School of Medicine and Biomedical Sciences, State University of New York at Buffalo.
authors.forename: F D
authors.initials: FD
authors.lastname: Nesti
authors.forename: B P
authors.initials: BP
authors.lastname: Fuhrman
authors.forename: D M
authors.initials: DM
authors.lastname: Steinhorn
authors.forename: M C
authors.initials: MC
authors.lastname: Papo
authors.forename: L J
authors.initials: LJ
authors.lastname: Hernan
authors.forename: L C
authors.initials: LC
authors.lastname: Duffy
authors.forename: J E
authors.initials: JE
authors.lastname: Fisher
authors.forename: C L
authors.initials: CL
authors.lastname: Leach
authors.forename: P R
authors.initials: PR
authors.lastname: Paczan
authors.forename: B A
authors.initials: BA
authors.lastname: Burak
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D005466:Fluorocarbons / Q000494:pharmacology*; D006439:Hemodynamics / Q000502:physiology; D011015:Pneumonia, Aspiration / Q000503:physiopathology; D011446:Prospective Studies; D011659:Pulmonary Gas Exchange / Q000187:drug effects*; D011897:Random Allocation; D012128:Respiratory Distress Syndrome / Q000503:physiopathology*; D012129:Respiratory Function Tests; D016037:Single-Blind Method; D013552:Swine; D013997:Time Factors
chemical_list: D005466:Fluorocarbons