title: High-frequency oscillatory ventilation does not decrease endothelin release in lung-lavaged rabbits.
abstract: High-frequency oscillatory ventilation (HFO) has been shown to reduce lung injury and pulmonary arterial pressure (PAP). We hypothesized that HFO leads to decreased endothelin 1 (ET-1) and endothelin 3 (ET-3) release when compared to conventional mechanical ventilation (CMV) in lung-lavaged rabbits.
  
  
  METHODS
  Prospective, randomized, controlled animal study. In 26 adult New Zealand White Rabbits ventilated by CMV or HFO under hypoxemic and normoxemic conditions after lung lavage (CMV-hypo: n = 5; CMV-normo: n = 8; HFO-hypo: n = 7; HFO-normo: n = 6) we recorded systemic and PAP, measured blood gases, ET-1 and ET-3 and calculated intrapulmonary venous admixture during a 4-h experiment. ET-1 was significantly increased after lavage (p < 0.05) with no further increase until the end of the experiment. Neither pulmonary arterial nor systemic arterial ET-1 differed between CMV and HFO or between hypoxemia and normoxemia. Systemic arterial ET-3, however, was significantly higher in HFO-hypo than in the other two groups ventilated under normoxemic conditions at the end of the experiment (HFO-hypo vs. CMV-normo, p < 0.05; HFO-hypo vs. HFO-normo, p < 0.05). PAP showed a continuous increase in all groups (p < 0.05). We did not find any correlation between PAP and ET-1 or ET-3. Intrapulmonary venous admixture increased in animals ventilated under hypoxemic conditions, whereas it decreased after lung lavage in those ventilated under normoxemic conditions until the end of the experiment (HFO-normo, p < 0.05).
  
  
  CONCLUSIONS
  This study suggests that HFO does not decrease ET-1 and ET-3 release compared to CMV in lung-lavaged rabbits. Hypoxemia, however, may increase ET-3 release from the lungs, leading to an increased intrapulmonary shunt.
authors.affiliation: Children's Hospital, Department of Biostatistics, University of Innsbruck, Austria. Burkhard.Simma@uibk.ac.at
authors.forename: B
authors.initials: B
authors.lastname: Simma
authors.forename: V
authors.initials: V
authors.lastname: Gülberg
authors.forename: P
authors.initials: P
authors.lastname: Schobel
authors.forename: R
authors.initials: R
authors.lastname: Trawöger
authors.forename: H
authors.initials: H
authors.lastname: Ulmer
authors.forename: A L
authors.initials: AL
authors.lastname: Gerbes
authors.forename: G
authors.initials: G
authors.lastname: Putz
mesh_terms: D000818:Animals; D001158:Arteries; D018893:Bronchoalveolar Lavage; D002245:Carbon Dioxide / Q000097:blood; D019332:Endothelin-1 / Q000097:blood; D019334:Endothelin-3 / Q000097:blood; D016232:Endothelins / Q000378:metabolism*; D006612:High-Frequency Ventilation / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D008168:Lung / Q000098:blood supply; D008297:Male; D010100:Oxygen / Q000097:blood; D011651:Pulmonary Artery; D011667:Pulmonary Veins; D011817:Rabbits
chemical_list: D019332:Endothelin-1; D019334:Endothelin-3; D016232:Endothelins; D002245:Carbon Dioxide; D010100:Oxygen