The Utility of Oxygen Insufflation During Flexible Fiberoptic Bronchoscope-guided Intubation

Study Overview
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Brief Summary
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This study investigate the utility of continuous oxygen insufflation during fiberoptic bronchoscope-guided intubation. One group receives oxygen via suction channel of fiberoptic bronchoscope during intubation. The other group does not receive oxygen during fiberoptic bronchoscope-guided intubation. Then, the velocity of deoxygenation difference of PaO2(baseline

Detailed Description
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Fiberoptic bronchoscope-guided intubation is a gold standard for intubation of a patient with anticipating difficult airway. This technique takes several minutes without oxygen supply, which results in hypoxia when it prolonged. If continuous supply of oxygen during procedure improve the oxygenation, we can reduce the risk of hypoxemia and increase the safety margin during procedure.

Official Title
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The Utility of Oxygen Insufflation During Flexible Fiberoptic Bronchoscope-guided Intubation

Conditions
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Lumbar Spinal Stenosis

Intervention / Treatment
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* Drug: Oxygen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients who have surgery under general oral endotracheal anesthesia with invasive arterial blood pressure monitoring Exclusion Criteria: history of lung disease abnormality in chest x-ray anticipating difficult intubation pregnant women who is unable to understand and agree the consent form

Ages Eligible for Study
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Minimum Age: 20 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Oxygen<br>Oxygen is supplied through suction port in bronchoscope during bronchoscope-guided intubation. | Drug: Oxygen<br>* Oxygen is supplied through suction port during bronchoscope-guided intubation.<br>|
| No Intervention: Control<br>Bronchoscope-guided intubation is performed without oxygen supply. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Velocity of PaO2 decrease | After administration of anesthetic agents and manual ventilation of 5 minutes, arterial blood sampling is collected. Then bronchoscope-guided intubation performed and arterial blood sample is collected immediately after the intubation completed. Time for intubation (between 1st and 2nd blood sample) is recorded. The difference of PaO2(before & after intubation) is divided by the time taking for intubation. | from mask removal to 1st manual ventilation after intubation, up to 5 minute | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| success of intubation | After 1st trial of intubation, the success of intubation is recorded. If it takes more than 300 sec, it will be considered failure. | 300 sec after the beginning of intubation | 
| PaO2 | arterial blood samples are collected before and after intubation. | 1. 5 minutes after manual ventilation / 2.right before 1st manual ventilation after intubation, up to 5 minute | 
| PaCO2 | arterial blood samples are collected before and after intubation. | 1. 5 minutes after manual ventilation / 2.right before 1st manual ventilation after intubation, up to 5 minute | 
| pH | arterial blood samples are collected before and after intubation. | 1. 5 minutes after manual ventilation / 2.right before 1st manual ventilation after intubation, up to 5 minute | 
| visual field | Visual field is evaluated by the blinded observer. It is evaluated as followed;excellent, good, poor, impossible | throughout the intubation with bronchoscope, upto 5 minute |