title: The glottic aperture seal airway: a new ventilatory device.
abstract: BACKGROUND
  None of the presently used airway devices are ideal regarding ease of insertion, alignment with the laryngeal inlet, and provision of a high-pressure seal from the environment. The purpose of this study was to determine, in awake volunteers, the performance of a new ventilatory device, the glottic aperture seal airway, regarding ease of insertion, alignment with the laryngeal inlet, and forced exhalation seal pressure (PFES).
  
  
  METHODS
  The glottic aperture seal airway consists of a curved tubular component that ends in the middle of an elliptical foam cushion glottic component. The posterior surface of the foam has a curved flexible plastic backing, which imparts a 60 degree angle between the proximal half and the distal half of the foam cushion. When the glottic aperture seal airway is properly in situ in a supine patient, the proximal half of the foam cushion is opposite the laryngeal inlet. The posterior surface of the plastic backing has a balloon attached to it. Inflation of the balloon presses the ventilation hole and foam cushion up against the laryngeal inlet, thereby creating a seal from the environment. Using the laryngeal mask airway as a control device, the glottic aperture seal airway was tested for time and ease of insertion, fiberoptic alignment with the laryngeal inlet, and PFES in 18 lightly sedated and locally anesthetized volunteers.
  
  
  RESULTS
  The glottic aperture seal and laryngeal mask airways were inserted with equal ease and speed. The fiberoptic alignment with the larynx was excellent for both the glottic aperture seal and laryngeal mask airways. In all volunteers, the mean +/- SD PFES values at 0-, 10-, 20-, 30-, and 40-ml balloon inflation volumes of the glottic aperture seal airway were 23.4 +/- 11.8, 29.6 +/- 12.4, 42.7 +/- 12.5, 56.9 +/- 5.6, and 60 +/- 0 cm H2O, respectively; the PFES at > or = 20 ml balloon inflation volume of the glottic aperture seal airway was significantly greater than with the laryngeal mask airway (19.4 +/- 6.7 cm H2O, P < 0.01). A PFES of > or =60 cm H2O was achieved with the glottic aperture seal airway in all volunteers (n = 2 at 10 ml, n = 3 at 20 ml, n = 9 at 30 ml, and n = 4 at 40 ml). The glottic aperture seal airway did not cause any trauma.
  
  
  CONCLUSIONS
  In awake volunteers, the glottic aperture seal and laryngeal mask airways were equally easy to insert and position. The glottic aperture seal airway was capable of achieving a higher PFES than the laryngeal mask airway.
authors.affiliation: Augustine Medical Incorporated, Eden Prairie, Minnesota, USA. jbenumof@UCSD.edu
authors.forename: J L
authors.initials: JL
authors.lastname: Benumof
mesh_terms: D000293:Adolescent; D000328:Adult; D000776:Anesthesiology / Q000295:instrumentation*; D004825:Epiglottis; D004867:Equipment Design; D005069:Evaluation Studies as Topic; D005260:Female; D005336:Fiber Optic Technology; D006801:Humans; D017214:Laryngeal Masks; D008297:Male; D012119:Respiration; D012122:Ventilators, Mechanical