Optimal Intubating Technique Using Videolaryngoscopy in Patients With Semi-rigid Neck Collar

Study Overview
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Brief Summary
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In the case of tracheal intubation using a video laryngoscope, both techniques, one is 'conventional technique' in which intubation is performed by placing the blade tip on the vallecula and the other is 'sliding technique' performed by sliding the blade under the epiglottis, are commonly conducted by anesthesiologists. Investigators would like to compare if the sliding technique can improve the condition of tracheal intubation in patients wearing semi-rigid neck collars in cervical spine surgery.

Detailed Description
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For patients who need to limit the movement of the cervical spine, the tracheal intubation becomes difficult because the head must be positioned in the neutral position. Most of all, with a semi-rigid neck collar that maintains the neutral position of the head and neck, movement is limited and the mouth is not well-opened make the environment of tracheal intubation worse, which result in hypoxia or throat complications related to general anesthesia. Fortunately, it is possible that the development of video laryngoscope assists tracheal intubation easier for patients who have the limited movement of the cervical spine. However, the preferred intubation style and instrument selection for each operator are varied; the established method is required. In the case of tracheal intubation using a video laryngoscope, both techniques, one is 'conventional technique' in which intubation is performed by placing the blade tip on the vallecula and the other is 'sliding technique' performed by sliding the blade under the epiglottis, are commonly conducted by anesthesiologists. Investigators would like to compare if the sliding technique can improve the condition of tracheal intubation in patients wearing semi-rigid neck collars in cervical spine surgery.

Official Title
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Comparison of Sliding Technique and Conventional Technique for Videolaryngoscopy in Patients Undergoing Cervical Spine Surgery With Semi-rigid Neck Collar During Intubation

Conditions
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Cervical Spine Surgery, Intubation;Difficult

Intervention / Treatment
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* Procedure: Sliding Intubating Technique


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Adult patients (over 19 years of age) with ASA class I-III undergoing cervical spine surgery at our institution in the department of spine neurosurgery Exclusion Criteria: When rapid sequence induction is required When awake intubation is required If a subject is on the medication for asthma If as subject cannot read or understand the consent form of study

Ages Eligible for Study
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Minimum Age: 20 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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Conventional Intubating Technique<br>'Conventional technique' means that endotracheal intubation is performed with the videolayngoscope blade lifting up the epiglottis. | |
| Experimental: Sliding Intubating Technique<br>'Sliding technique' means that endotracheal intubation is performed by sliding the videolayngoscope blade under the epiglottis smoothly. | Procedure: Sliding Intubating Technique<br>* Sliding technique' means that endotracheal intubation is performed by sliding the videolayngoscope blade under the epiglottis smoothly.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| percentage of glottic opening (POGO) score (%) | The POGO score represents the percentage of glottic opening seen, defined by the linear span from the anterior commisure to the interarytenoid notch. | When we insert the endotracheal tube during anesthetic induction |