title: Combination of tracheal gas insufflation and airway pressure release ventilation.
abstract: OBJECTIVE
  We hypothesized that the continuous gas flow administration delivered through an insufflation catheter positioned above the carina during airway pressure release ventilation (APRV) would facilitate carbon dioxide (CO2) elimination, resulting in normocarbia with a substantially reduced peak airway pressure (Paw). To test this hypothesis, we compared intermittent positive pressure ventilation (IPPV), tracheal gas insufflation (TGI), APRV, and combined TGI and APRV (TGI + APRV).
  
  
  METHODS
  Animal study with random application of four ventilatory modes in a canine restrictive-thorax model with and without pulmonary edema.
  
  
  METHODS
  Research laboratory at Kumamoto (Japan) University School of Medicine.
  
  
  METHODS
  Six mongrel dogs.
  
  
  METHODS
  Application of four ventilatory modes (IPPV, TGI, APRV, and TGI + APRV).
  
  
  RESULTS
  TGI + APRV facilitated CO2 elimination. The peak Paw was significantly lower during TGI + APRV than during IPPV (nonpulmonary edema model; 15 +/- 4 vs 28 +/- 9 cm H2O; p < 0.05; pulmonary edema model: 20 +/- 4 vs 34 +/- 10 cm H2O; p < 0.05). Normocarbia was observed in both models. Neither TGI nor APRV alone maintained normocarbia.
  
  
  CONCLUSIONS
  The combined use of TGI and APRV is a more effective method of maintaining normocarbia with reduced peak Paw than either IPPV or APRV alone.
authors.affiliation: Department of Anesthesiology, Kumamoto University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Okamoto
authors.forename: H
authors.initials: H
authors.lastname: Kishi
authors.forename: H
authors.initials: H
authors.lastname: Choi
authors.forename: T
authors.initials: T
authors.lastname: Sato
mesh_terms: D000818:Animals; D001794:Blood Pressure; D002245:Carbon Dioxide / Q000097:blood / Q000378:metabolism; D002302:Cardiac Output; D002496:Central Venous Pressure; D004285:Dogs; D006339:Heart Rate; D006935:Hypercapnia / Q000209:etiology; D007327:Insufflation; D007385:Intermittent Positive-Pressure Ventilation; D008170:Lung Compliance; D010100:Oxygen / Q000097:blood; D011175:Positive-Pressure Respiration; D011312:Pressure; D011654:Pulmonary Edema / Q000628:therapy; D012123:Pulmonary Ventilation; D011669:Pulmonary Wedge Pressure; D011897:Random Allocation; D012121:Respiration, Artificial / Q000379:methods*; D013909:Thorax; D014132:Trachea; D014692:Ventilation-Perfusion Ratio
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen