Comparison of the Videolaryngoscopes With Manual In-line Stabilization

Study Overview
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Brief Summary
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Videolaryngoscope is useful to improve the laryngeal view, especially during difficult intubation. There are several kinds of videolaryngoscopes and it is applicable during nasotracheal intubation. In this study, the investigators will compare the McGrath videolaryngoscope and Pentax-AWS with Macintosh laryngoscope for nasotracheal intubation in patients with manual in-line stabilization.

Official Title
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Comparison of the McGrath Videolaryngoscope and the Pentax-AWS With the Macintosh Laryngoscope for Nasotracheal Intubation in Patients With Manual In-line Stabilization

Conditions
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Oral Surgery, Maxillofacial Surgery

Intervention / Treatment
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* Procedure: MILS
* Device: McGrath videolaryngoscope
* Device: Pentax AWS videolaryngoscope
* Device: Macintosh laryngoscope


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: oral or maxillofacial surgery ASA class I, II Exclusion Criteria: anticipated difficult intubation necessity for rapid sequence induction cervical spine injury bleeding tendency

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: McGrath Group<br>MgGrath videolaryngoscope will be used for nasotracheal intubation with MILS | Procedure: MILS<br>* MILS(Manual in-line stabilization) will be applied during intubation. With MILS, different kinds of laryngoscope will be evaluated in a simulated difficult airway.<br>Device: McGrath videolaryngoscope<br>* McGrath videolaryngoscope will be used for intubation<br>|
| Experimental: Pentax-AWS Group<br>Pentax-AWS videolaryngoscope will be used for nasotracheal intubation with MILS | Procedure: MILS<br>* MILS(Manual in-line stabilization) will be applied during intubation. With MILS, different kinds of laryngoscope will be evaluated in a simulated difficult airway.<br>Device: Pentax AWS videolaryngoscope<br>* Pentax AWS videolaryngoscope will be used for intubation<br>|
| Experimental: Macintosh Laryngoscope Group<br>Macintosh Laryngoscope will be used for nasotracheal intubation with MILS | Procedure: MILS<br>* MILS(Manual in-line stabilization) will be applied during intubation. With MILS, different kinds of laryngoscope will be evaluated in a simulated difficult airway.<br>Device: Macintosh laryngoscope<br>* Macintosh laryngoscope will be used for intubation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| time for intubation |  | from holding the laryngoscope until the 1st ventilation after intubation, within 90 seconds | 
| Cormack Lehane Laryngeal view |  | when laryngoscope is appropriately placed during intubation, approximately 2 seconds | 
| POGP score | Percentage of glottic opening(POGO) | when laryngoscope is appropriately placed during intubation, approximately 2 seconds | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| external laryngeal manipulation | When the laryngeal view is insufficient during laryngoscope, another physician can manipulate the larynx externally to improve the laryngeal view. The necessity of external laryngeal manipulation will be recorded. | when laryngoscope is appropriately placed during intubation, approximately 2 seconds | 
| magill forceps | when the nasotracheal tube can not introduced to vocal cord manually, magill forceps can hold the tube to advance the tube through vocal cord. The necessity of magill forceps during intubation will be recorded | when laryngoscope is appropriately placed during intubation, approximately 5 seconds | 
| IDS (intubation difficulty scale) | IDS score is the sum of the following seven variables: N1: the number of intubation attempts>1 N2: the number of operators. 1 N3: the number of alternative intubation techniques used N4: glottic exposure (Cormack Lehane grade minus 1) N5: Lifting force required during laryngoscopy (0=normal; 1=increased) N6: necessity for external laryngeal pressure (0=not applied; 1=applied) N7: position of the vocal cords at intubation (0=abduction/ not visualized; 1=adduction) | during intubation, approximately 90 seconds | 
| numeric rating scale for intubation | 0-10 (0; no difficulty, 10: hardest) | during intubation, approximately 90 seconds | 
| grade of bleeding | After confirmation of successful intubation, Yankauer suction was introduced to access the intraoral bleeding during intubation. Grade is 4 points scale (none/trace/moderate/severe). | 10 seconds after completion of intubation |