GlideScope®Video Laryngoscope for Difficult Intubation: Implication of the Size of Blade
The investigators evaluated the usefulness of the Glidescope(GVL) compared with direct laryngoscopy in patients whose airway management are anticipated difficult (C&L grade ≥3) by comparing the laryngoscopic view. Also, the investigators compared the effectiveness of smaller-size blade of GVL (GVLs) with standard blade of GVL selected by patient's weight (GVLw) in the same patients.
Device: Macintosh laryngoscope
Device: GVL selected by weight
Device: smaller sized GVL
|Study Design:||Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
|Official Title:||GlideScope®Video Laryngoscope for Difficult Intubation: Implication of the Size of Blade|
- The Differences in the Glottis View (C&L Grade) of Macintosh Laryngoscope and GVL Selected by Weight. [ Time Frame: up to 1 day of surgery ] [ Designated as safety issue: Yes ]
Glottis view was scored using C&L grade by Macintosh laryngoscope and GVL selected by weight, and compared each other.
We used modified C&L grade: grade 1, all or most of the glottic aperture was visible; grade 2a, posterior cords and cartilage visible; grade 2b, only posterior cartilage visible; grade 3a, epiglottis visible and can be lifted; grade 3b, epiglottis adherent to the posterior pharynx; and grade 4, the epiglottis could not be visualized.
For the statistical analysis, the modified C&L grade was converted to an ordinal scale; grade 1 to 1, grade 2a to 2, grade 2b to 3, grade 3a to 4, grade 3b to 5, and grade 4 to 6. Therefore, score range for the data reported in the table was between 1 and 6, with 1 representing best view and 6 representing no view.
- The Differences in the Glottis View (C&L Grade) of GVL Selected by Weight and Smaller Sized GVL [ Time Frame: up to 1day of surgery ] [ Designated as safety issue: Yes ]
Glottis view was scored using C&L grade by GVL selected by weight and smaller sized GVL, and compared each other.
Score range for the data reported in the table was between 1 and 6, with 1 representing best view and 6 representing no view.
|Study Start Date:||February 2011|
|Study Completion Date:||January 2012|
|Primary Completion Date:||January 2012 (Final data collection date for primary outcome measure)|
glottis view assessment
Glottis view assessment using Macintosh laryngoscope & GVL selected by weight & smaller sized GVL in single patient
Device: Macintosh laryngoscope
Glottis view assessment by direct visualization using Macintosh laryngoscopeDevice: GVL selected by weight
Glottis view assessment by GVL selected by weight which is usually selected first
Other Name: GlideScope® videolaryngoscopy selected by weightDevice: smaller sized GVL
Glottis view assessment by GVL which is smaller in one size than GVL selected by age
Other Name: smaller sized GlideScope® videolaryngoscopy
We assumed that smaller sized GVL can slide more angulated along the tongue, so the tip of a blade can be placed more anterior and cephalad. The angle of camera would be optimized by inserting the blade further with the blade tip directed toward the larynx. This optimization may be more remarkable with smaller blade because it can be inserted with rotation. Furthermore, the location and the angle of camera are different according to GVL blade size. Considering that patient with difficult airway has hypognathia and more cephalad larynx, it may be helpful with smaller sized GVL (GVLs) rather than GVL selected by weight (GVLw) for improvement of laryngoscopic view in patients with difficult airways. We hypothesized that GVLs can provide better laryngoscopic view than GVLw and DL in patient with difficult airway.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01616771
|Study Director:||Jin-Tae Kim, professor||Seoul National University Hospital|