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.

Study Overview

• Status: Completed
• Conditions: Intubation; Difficult
• Intervention / Treatment: Device: Macintosh laryngoscope; Device: GVL selected by weight; Device: smaller sized GVL

Detailed Description

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.

• Study Type: Interventional
• Enrollment (Actual): 23
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Patients whose C&L grade were over 3 in previous anesthetic records.

Exclusion Criteria:

• Patients with pulmonary aspiration, increased intracranial pressure, and severe cardiovascular disease

Study Plan

How is the study designed?

Design Details

• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Other: 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 laryngoscope; Device: GVL selected by weight; Glottis view assessment by GVL selected by weight which is usually selected first; Other Names: GlideScope® videolaryngoscopy selected by weight; Device: smaller sized GVL; Glottis view assessment by GVL which is smaller in one size than GVL selected by age; Other Names: smaller sized GlideScope® videolaryngoscopy

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Differences in the Glottis View (C&L Grade) of Macintosh Laryngoscope and GVL Selected by Weight.	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.	up to 1 day of surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Differences in the Glottis View (C&L Grade) of GVL Selected by Weight and Smaller Sized GVL	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.	up to 1day of surgery

Collaborators and Investigators

• Sponsor: Seoul National University Hospital
• Investigators: Study Director: Jin-Tae Kim, professor, Seoul National University Hospital

Study record dates

Study Major Dates

• Study Start: February 1, 2011
• Primary Completion (Actual): January 1, 2012
• Study Completion (Actual): January 1, 2012

Study Registration Dates

• First Submitted: April 30, 2012
• First Submitted That Met QC Criteria: June 11, 2012
• First Posted (Estimate): June 12, 2012

Study Record Updates

• Last Update Posted (Estimate): November 4, 2014
• Last Update Submitted That Met QC Criteria: November 3, 2014
• Last Verified: November 1, 2014

More Information

Terms related to this study

• Keywords: laryngoscopes
• Other Study ID Numbers: H-1111-037-385

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No