title: An optimal dose of perfluorocarbon for respiratory mechanics in partial liquid ventilation for dependent lung-dominant acute lung injury.
abstract: BACKGROUND
  Despite increasing knowledge about partial liquid ventilation (PLV), the optimal dose of perfluorocarbon (PFC) is not yet established. Because there exist normal regions in the lung with ARDS and because PLV in the normal lung results in worsened gas exchange, we postulated that the optimal dose of PFC for PLV may be less than the functional residual capacity (FRC) dose in the lung with limited disease.
  
  
  METHODS
  Animal study at the Asan Institute for Life Sciences, Seoul, Korea.
  
  
  METHODS
  Twelve rabbits in which dependent lung-dominant lung injury was created by a modified saline solution lavage.
  
  
  METHODS
  PLV performed at six different doses of perfluorodecalin in sequence (3, 6, 9, 12, 15, and 18 mL/kg every 15 min).
  
  
  RESULTS
  Our modified saline solution lavage induced atelectasis and hemorrhage confined to the dependent lung with severe hypoxia (PaO(2)/fraction of inspired oxygen = 37 +/- 6 mm Hg). Peak airway pressure (Ppeak) and inspiratory pause pressure (Ppause) with PLV were lower at doses of 3 to 15 mL/kg (all p < 0.05), but not different at a dose of 18 mL/kg, when compared with gas ventilation. Ppeak increased at doses of 12, 15, and 18 mL/kg, when each was compared with the preceding PFC dose. At increasing PFC doses, the change in the elastic component of airway pressure (Ppause after minus Ppause before) was negative until the dose of 9 mL/kg, but was positive at doses of 12 mL/kg and above. The change in the resistive component ([Ppeak minus Ppause] after minus [Ppeak minus Ppause] before) was negative until the dose of 6 mL/kg, but was positive at the dose > or = 9 mL/kg.
  
  
  CONCLUSIONS
  Respiratory mechanics during PLV for dependent lung-dominant lung injury were optimal at a PFC dose less than the FRC.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: C M
authors.initials: CM
authors.lastname: Lim
authors.forename: Y
authors.initials: Y
authors.lastname: Koh
authors.forename: B O
authors.initials: BO
authors.lastname: Jung
authors.forename: S D
authors.initials: SD
authors.lastname: Lee
authors.forename: W S
authors.initials: WS
authors.lastname: Kim
authors.forename: D S
authors.initials: DS
authors.lastname: Kim
authors.forename: W D
authors.initials: WD
authors.lastname: Kim
mesh_terms: D000818:Animals; D018893:Bronchoalveolar Lavage / Q000009:adverse effects; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005466:Fluorocarbons / Q000008:administration & dosage*; D005652:Functional Residual Capacity / Q000187:drug effects; D007322:Instillation, Drug; D010952:Plasma Substitutes / Q000008:administration & dosage*; D011175:Positive-Pressure Respiration / Q000379:methods*; D011659:Pulmonary Gas Exchange / Q000187:drug effects; D011817:Rabbits; D012128:Respiratory Distress Syndrome / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D015656:Respiratory Mechanics / Q000187:drug effects*; D014132:Trachea; D016896:Treatment Outcome
chemical_list: D005466:Fluorocarbons; D010952:Plasma Substitutes; C008805:perfluorodecalin