title: Usefulness of continuous oxygen insufflation into trachea for management of upper airway obstruction during anesthesia.
abstract: BACKGROUND
  Severe complications associated with upper airway obstruction often occur during the perioperative period. Development of a simple and reliable technique for reversing the impaired airway patency may improve airway management. The purpose of the current study is to evaluate the usefulness of transtracheal oxygen insufflation (TTI) for management of upper airway obstruction during anesthesia and to explore the mechanisms of TTI in detail.
  
  
  METHODS
  During propofol anesthesia in eight spontaneously breathing patients, the upper airway cross-sectional area and pressure-flow measurements during neck flexion with TTI were compared with those during triple airway maneuvers (TAM) without TTI. Blood gas analyses assessed efficacy of CO2 elimination during TTI in an additional nine patients.
  
  
  RESULTS
  TTI achieved adequate PaCO2 and PaO2 levels equivalent to those during TAM. In addition to a significantly smaller cross-sectional area during TTI, the location and slope of the pressure-flow relation during TTI completely differed from those during TAM, indicating that upper airway resistance was much higher during TTI. Notably, minute ventilation during TTI was significantly smaller than that during TAM, suggesting reduced dead space or other mechanisms for CO2 elimination.
  
  
  CONCLUSIONS
  TTI is capable of maintaining adequate blood gases through mechanisms different from those of conventional airway support in anesthetized subjects with upper airway obstruction.
authors.affiliation: Chiba University School of Medicine, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Okazaki
authors.forename: S
authors.initials: S
authors.lastname: Isono
authors.forename: A
authors.initials: A
authors.lastname: Tanaka
authors.forename: Y
authors.initials: Y
authors.lastname: Tagaito
authors.forename: A R
authors.initials: AR
authors.lastname: Schwartz
authors.forename: T
authors.initials: T
authors.lastname: Nishino
mesh_terms: D000328:Adult; D000368:Aged; D000402:Airway Obstruction / Q000628:therapy*; D000768:Anesthesia, General; D018686:Anesthetics, Intravenous; D000818:Animals; D001784:Blood Gas Analysis; D006801:Humans; D007327:Insufflation; D007431:Intraoperative Complications / Q000628:therapy*; D008875:Middle Aged; D010100:Oxygen / Q000008:administration & dosage* / Q000627:therapeutic use; D015742:Propofol; D014132:Trachea
chemical_list: D018686:Anesthetics, Intravenous; D010100:Oxygen; D015742:Propofol