title: Low-flow transtracheal rescue insufflation of oxygen after profound desaturation.
abstract: BACKGROUND
  The objective of this study was to determine whether low-flow transtracheal insufflation of oxygen (TRIO) could rescue an animal from profound desaturation. This temporizing maneuver could be useful during cannot-intubate or -ventilate scenarios by resolving hypoxia without the morbidity associated with more invasive procedures.
  
  
  METHODS
  Seven swine for a total of 12 runs were studied. Animals were pharmacologically anesthetized, paralyzed, and mechanically ventilated with room air. After disconnection from the ventilator and desaturation to an Spo2 < 50%, low-flow TRIO (2 L/min) was administered for 1 hour.
  
  
  RESULTS
  All animals survived and Spo2 increased to greater than 90% in 23 seconds on average. Pao2 (mean, 183 mm Hg) remained elevated throughout the study. Hemodynamic stability was maintained for at least 15 minutes.
  
  
  CONCLUSIONS
  Low-flow TRIO rescued animals from profound hypoxia and maintained oxygenation for at least 1 hour. Low-flow TRIO did not prevent hypercarbia with its subsequent sympathetic activation.
authors.affiliation: Walter Reed Army Institute of Research, Silver Spring, Maryland, USA. ian.h.black@us.army.mil
authors.forename: Ian H
authors.initials: IH
authors.lastname: Black
authors.forename: Scott A
authors.initials: SA
authors.lastname: Janus
authors.forename: Kurt W
authors.initials: KW
authors.lastname: Grathwohl
mesh_terms: D000818:Animals; D001049:Apnea / Q000000981:diagnostic imaging / Q000503:physiopathology; D002302:Cardiac Output; D006439:Hemodynamics; D000860:Hypoxia / Q000628:therapy*; D007327:Insufflation / Q000379:methods*; D010100:Oxygen / Q000008:administration & dosage* / Q000097:blood*; D013552:Swine; D014057:Tomography, X-Ray Computed; D014132:Trachea
chemical_list: D010100:Oxygen