Modified Angled Tube vs. Conventional Angled Tube in Double-lumen Endotracheal Tube Intubation

Study Overview
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Brief Summary
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The investigators are trying to compare the individually modified-angled tube and the conventional-angled tube in ease of double lumen endotracheal tube insertion and the incidence of related postoperative complications.

Detailed Description
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Inserting a double lumen endotracheal tube is somewhat more difficult than a single lumen tube intubation because of its larger outer diameter and the more rigid feature. Moreover, the airway axes (oral-,pharyngeal-, and laryngotracheal axis) are not always straight under sniffing condition. Therefore, to make easy to insert a double-lumen tube and reduce the tube-related complications, we are trying to compare the individually angle-modified tube and the manufacturer-provided-angled tube.

Official Title
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Comparison of Individually Modified Angled Tube and Conventional Angled Tube in Double-lumen Endotracheal Tube Intubation: A Randomized Clinical Trial

Conditions
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Intubation, Intratracheal, Thoracic Surgical Procedures

Intervention / Treatment
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* Device: Mallinckrodt endotracheal tube with a modified angle
* Device: Mallinckrodt endobronchial tube with a conventional angle


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects undergoing thoracic surgery under one lung ventilation Subjects older than 20 yrs who can give written informed consent Exclusion Criteria: Those who need rapid sequence intubation Those with cervical spinal disease (cervical spinal injury, rheumatoid arthritis with atlantoaxial subluxation) Those with oropharyngeal obstructive disease (including tumor, foreign body) Those who are expected prolonged intubation after surgery Those who are pregnant

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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No

Study Plan
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How is the study designed?
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Design Details

Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Control group<br>Intubating a manufacturer-provided-angled double-lumen tube (=Conventional-angled group,MallinckrodtTM endotracheal tube, Covidien) | Device: Mallinckrodt endobronchial tube with a conventional angle<br>* Inserting a manufacturer-provided conventional-angled tube<br>* Other names: Mallinckrodt endobronchial tube, Covidien, with conventional-angled tube;|
| Experimental: Tube angle modification<br>The angle of the double lumen tube(MallinckrodeTM endotracheal tube) is modified individually.At sniffing position, the distal tip of the tube is placed at the patient's cricoid cartilage level and the tube is bent at the intersection point of the two airway axes (oropharyngeal axis and tracheal axis) with an angle between the two axes. | Device: Mallinckrodt endotracheal tube with a modified angle<br>* At sniffing position, the distal tip of a double-lumen tube is located at the patient's cricoid cartilage level and then the tube is bent at the intersection point of oral axis and the pharyngolaryngeal axis with an angle between the two axes.<br>* Other names: (MallinckrodeTM endotracheal tube, Covidien);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The time taken to intubate a double-lumen tube | The time taken to insert the tube begins when the laryngoscope passes the patient's lips and ends when the tube passes the vocal cords | within 60 sec | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The number of attempts needed for successful intubation |  | Intubation | 
| The time taken for the first attempt of intubation |  | within 60 sec | 
| Postoperative sore throat, hoarseness or dysphagia |  | 30 minutes and 24hours after extubation |