title: The effect of bronchoscope rotation on tracheal tube orientation at the glottic level in a mannequin.
abstract: OBJECTIVE
  This study examined the effect of external fibreoptic bronchoscope (FOB) rotations on endotracheal tube (ETT) orientations at the glottic level.
  
  
  METHODS
  Using a mannequin, a nasal FOB was inserted for image capture. A second FOB with a preloaded ETT taped to its top was inserted orally into mid-trachea. The FOB with the taped ETT was rotated as a unit in the axial plane to five different external angles (-90°, -45°, 0°, +45°, +90°). At each external rotation, the ETT was advanced into the trachea. The image of the ETT at the glottic level was captured. Endotracheal tube orientation was quantified according to the glottic zone faced by the ETT. The ETT orientations were compared amongst the five external FOB rotations using the Kruskal-Wallis Test, while the ETT orientations at -90°, -45°, +45°, and +90° FOB rotations were compared with 0° rotation using the Mann-Whitney U test.
  
  
  RESULTS
  There was a significant difference in the ETT orientations amongst the five FOB rotations (P < 0.001). The ETT orientations at -90°, -45°, +45°, and +90° FOB rotations were different from the 0° rotation (P < 0.001 for all comparisons). A -90° FOB rotation was most effective in turning the ETT tip away from the right laryngeal structures and the interarytenoid tissue.
  
  
  CONCLUSIONS
  With the ETT loaded on a FOB, rotation of the FOB prior to advancing the ETT is effective in changing the ETT orientation at the glottis. A -90° FOB rotation is most effective in turning the ETT tip away from the right laryngeal structures and interarytenoid tissue.
authors.affiliation: Department of Anesthesia, Toronto Western Hospital, University of Toronto, MC2-405, 399 Bathurst Street, Toronto, ON M5T 2S8, Canada. david.wong@uhn.on.ca
authors.forename: David T
authors.initials: DT
authors.lastname: Wong
authors.forename: Brian
authors.initials: B
authors.lastname: Yau
authors.forename: Shikha
authors.initials: S
authors.lastname: Thapar
authors.forename: Sanjib D
authors.initials: SD
authors.lastname: Adhikary
mesh_terms: D020680:Bronchoscopes; D001999:Bronchoscopy / Q000379:methods*; D005336:Fiber Optic Technology; D005931:Glottis; D006801:Humans; D007442:Intubation, Intratracheal / Q000379:methods*; D008348:Manikins; D012399:Rotation; D018709:Statistics, Nonparametric