Endotracheal Tube Shapes for Intubation With Videolaryngoscope

Study Overview
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Brief Summary
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In this study, investigators will compare the efficacy of two shapes of endotracheal tube molded by stylet in endotracheal intubation using videolaryngoscope (McGrath MAC®). The participants will randomly be divided into two groups; J-shaped tube and 60-degrees-curved tube.

Detailed Description
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Since the intubation using videolaryngoscope does not need straightened oral-pharyngeal-laryngeal axis, certain curvature of endotracheal tube is needed for the successful intubation using the videolaryngoscope. Participants in both groups will be intubated with videolaryngoscope (McGrath MAC®). Stylet will be inserted in the endotracheal tubes and will be bent to a specific shape by the assigned group. In the J-shaped tube group, endotracheal tube will be molded to a shape similar to the blade of the videolaryngoscope (McGrath MAC®). In the 60-degrees-curved tube group, endotracheal tube will be bent 60 degrees. Time to intubation, intubation attempts and ease of intubation wil be assessed.

Official Title
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Comparison of Endotracheal Tube Shapes for Intubation With Videolaryngoscope in Normal Airways

Conditions
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Anesthesia

Intervention / Treatment
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* Device: J shaped stylet used for endotracheal intubation
* Device: 60-degrees stylet used for endotracheal intubation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients scheduled for the surgery under general anesthesia Adult patients from 18 years to 65 years American society of Anesthesiologist physical status 1,2,3 Exclusion Criteria: Previously diagnosed for the difficult intubation Pregnancy Obesity (Body mass index over 40 g/m^2)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: J-shaped<br>Endotracheal tube will be molded into a J-shape that is similar to that of Macintosh type blade of a McGrath MAC® videolaryngoscope. | Device: J shaped stylet used for endotracheal intubation<br>* After inserting a stylet into the endotracheal tube, the tube will be molded into a J-shape.<br>|
| Active Comparator: 60-degrees<br>Endotracheal tube will be bent 60 degrees. | Device: 60-degrees stylet used for endotracheal intubation<br>* After inserting a stylet into the endotracheal tube, the tube will be bent 60-degrees.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to intubate | the time took from the blade passing through the incisor teeth of the patient to the first end tidal CO2 appears on the anesthesia monitor screen. | 20 minutes after induction started. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Numbers of intubation attempts | numbers of attempts for the successful endotracheal intubation | 20 minutes after induction started. | 
| Level of difficulty in intubation | easy, moderate, difficult | 20 minutes after induction started. |