Optimal Insertion Depth of FOB for Oral FOB Intubation

Study Overview
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Brief Summary
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For oral fiberoptic intubation, the preliminary insertion depth of the fiberoptic bronchoscope should be important because the excessive insertion depth or too shallow depth might be the reason why the clinicians cannot perform oral fiberoptic intubation completely. The purpose of the study is to find out the optimal preliminary insertion depth of the fiberoptic bronchoscope for visualization of glottic opening in oral fiberoptic intubation.

Detailed Description
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For oral fiberoptic intubation, the preliminary insertion depth of the fiberoptic bronchoscope should be important because the excessive insertion depth or too shallow depth might be the reason why the clinicians cannot perform oral fiberoptic intubation completely. The purpose of the study is to find out the optimal preliminary insertion depth of the fiberoptic bronchoscope for visualization of glottic opening in oral fiberoptic intubation. The investigators will enroll the subjects of the present study after obtaining the written consent. After enrollment, the investigators will measure some anatomical distance, such as patient height. After induction of anesthesia and muscle relaxation for tracheal intubation, An investigator who has experiences of numerous fiberoptic intubation will measure the optimal preliminary insertion depth of the fiberoptic bronchoscope from the philtrum, the upper lip, or the incisors for oral fiberoptic intubation, with the aid of assistants. Then, tracheal intubation with a laryngoscope as a routine manner of our institute. The investigators will calculate the mean value of the optimal depth and find out an formula for that from our data.

Official Title
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Optimal Preliminary Insertion Depth of Fiberoptic Bronchoscope for Visualization of Glottic Opening in Oral Fiberoptic Intubation

Conditions
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General Anesthesia

Intervention / Treatment
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* Other: Oral FOB


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients requiring tracheal intubation for general anesthesia Exclusion Criteria: do not agree to participate in the study emergency surgery predicted difficult intubation very weak teeth (especially central teeth)

Ages Eligible for Study
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Minimum Age: 19 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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Oral FOB|After induction of anesthesia and muscle relaxation, An investigator who has experiences of numerous fiberoptic intubations will measure the optimal preliminary insertion depth of the fiberoptic bronchoscope for oral fiberoptic intubation.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The length of optimal preliminary insertion depth of FOB (centimeters) | The length of optimal preliminary insertion depth of FOB means the insertion depth of it from the philtrum, the upper lip, or the incisors where the clinicians can see easily the glottic opening while they are flexing the FOB. And that will be recorded as centimeters. | during tracheal intubation |