title: Manual translaryngeal jet ventilation and the risk of aspiration in a canine model.
abstract: OBJECTIVE
  Manual translaryngeal jet ventilation (TLJV) is a safe and effective method of maintaining normal ventilation in apneic subjects. Little data exist on the amount of airway protection afforded with this technique of airway management. We sought to evaluate the risk of aspiration during manual TLJV.
  
  
  METHODS
  Data were collected in a laboratory animal model.
  
  
  METHODS
  A prospective, nonrandomized, controlled trial was performed.
  
  
  METHODS
  Seventeen adult apneic mongrel dogs were enrolled.
  
  
  METHODS
  Intratracheal Gastrograffin was instilled and radiographic changes assessed during ventilation using a 0 to 3 scale (none to severe). Thirty-six trials were performed, with equal numbers at both 30 degrees and 45 degrees head elevation. The three groups studied were animals without airway protection (control), animals with a cuffed endotracheal tube (tube), and animals with a percutaneous TLJV cannula and a 50-psi oxygen source ventilated at a rate of 20 breaths per minute (jet).
  
  
  RESULTS
  Significantly less radiographic evidence of aspiration was noted in the jet and tube groups at 30 degrees and 45 degrees compared with control animals (P = .002 each). At 45 degrees head elevation a trend toward increased aspiration scores in the jet group compared with the tube group (P = .065) was observed.
  
  
  CONCLUSIONS
  In our model, manual TLJV at 20 breaths per minute and an I:E ratio of 1:2 provided protection from aspiration comparable to that observed with a cuffed endotracheal tube at 30 degrees head elevation. At 45 degrees elevation, this protection was diminished.
authors.affiliation: Division of Emergency Medicine, University of Pittsburgh, Pennsylvania.
authors.forename: D M
authors.initials: DM
authors.lastname: Yealy
authors.forename: M C
authors.initials: MC
authors.lastname: Plewa
authors.forename: J J
authors.initials: JJ
authors.lastname: Reed
authors.forename: R M
authors.initials: RM
authors.lastname: Kaplan
authors.forename: K
authors.initials: K
authors.lastname: Ilkhanipour
authors.forename: R D
authors.initials: RD
authors.lastname: Stewart
mesh_terms: D000818:Animals; D001049:Apnea / Q000628:therapy*; D004195:Disease Models, Animal; D004285:Dogs; D006257:Head; D006611:High-Frequency Jet Ventilation / Q000009:adverse effects / Q000379:methods*; D008297:Male; D011015:Pneumonia, Aspiration / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology*; D011187:Posture; D011446:Prospective Studies; D011859:Radiography; D012307:Risk Factors