Comparison of Video Laryngoscope Using Miller or Macintosh Approach During Endotracheal Intubation

Not Applicable

Completed

• Conditions: Difficult Intubation
• Interventions: Procedure: Video laryngoscope with Miller approach

• Registration Number: NCT05545982
• Lead Sponsor: Kaohsiung Veterans General Hospital.

Brief Summary

Video laryngoscope has become recommended option during difficult intubation. Guidelines of ASA at 2013 had suggested using video laryngoscope after failure intubation of direct laryngoscope. Varieties of video laryngoscope had been invented with different curves. We call the one which has the same curve of Macintosh laryngoscope as conventional video laryngoscope in this study. Mostly, the way of using conventional video laryngoscope is suggested as Macintosh method. However, with the front positioning camera, Miller method can theoretically improve the glottic opening. We intend to discuss whether using Miller approach with conventional video laryngoscope can improve glottic opening or not.

Detailed Description

Video scope can provide better glottic opening by increase the tilting angle of the tip, and the position of camera can provide larger vision angle. However, while the angle increases, the endotracheal tube must fallow the curve, which may require learning curve of the operator. In Glidescope as example, increase the tilting angle can help with glottic exposure, however the steep curve will simultaneously increase the difficulty of inserting the tube or using Magill forceps, especially while intubating double lumen or nasal endotracheal tube. Conventional video laryngoscope in this study indicates the video laryngoscope blade which has the same curve as Macintosh laryngoscope. It mainly improves the glottic view by front positioning camera.

Anesthesiologist usually place the tip of the blade at vallecula to expose the glottic which is the conventional ways of using Macintosh blade which we name it as Macintosh method. Placing the tip below the epiglottis and lift it up directly is the way of using Miller blade. Theoretically, the Miller method with conventional video laryngoscope may improve the scale of glottic exposure measured with Cormack-Lehane grade. This is a one-group pretest-posttest study to compare the Cormack-Lehane grade with two different methods in the same patient. This study tends to discuss whether this combination can improve the glottic exposure and preserve the advantage of direct laryngoscope.

Study Timeline

• Study Start: 2019-10-04
• Primary Completion: 2021-11-22
• Study Completion: 2021-11-22
• Status Verified: 2022-09
• Study First Submitted: 2022-09-07
• Study First Submitted QC: 2022-09-15
• Last Update Submitted: 2022-09-15
• Study First Posted: 2022-09-19
• Last Update Posted: 2022-09-19

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 247

Inclusion Criteria

1. Aged>20
2. Scheduled to received operation that required general anesthesia with endotracheal tube [3] ASA I, II

Exclusion Criteria

1. Emergent surgery
2. pregnant
3. Limited mouth opening
4. Poor dental condition
5. Airway obstruction (oral tumor, hypopharyngeal cancer....etc)
6. Deep neck infection
7. Allergic to any anesthetic

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Intubation with Miller approach	Video laryngoscope with Miller approach	Posttest group: Patient receive intubation with conventional video laryngoscope with Miller approach. Pretest group: Patient receive intubation with conventional video laryngoscope with Macintosh approach.

Primary Outcome Measures

Name	Time	Method
Change of cormack lehane grade	Measured from glottic exposed by Macintosh approach to Miller approach. Record the cormack lehane grade. The whole precess will be completed within 5 minutes if there are no difficult intubation.	Compare the difference of cormack lehane grade using Macintosh ot Miller approach.(cormack lehane grade has four gradings. Grade 1 represent entire glottic opening. Grade 4 represent vocal cord cab not be seen)

Secondary Outcome Measures

Name	Time	Method
Post intubation adverse event	Visit the patient daily at post operation day 1 and record any adverse event until post operation day3 or the patient is discharged.	Some adverse events are often seen after intubation, such as sore throat, hoarseness....etc.

Trial Locations

Locations (1)

Kaohsiung Veterans General Hospital; 🇨🇳 Kaohsiung, Taiwan