Adequate Additional Bronchial Cuff Volume to Achieve Blood-tight Seal After Air-tight Seal in Double Lumen Tube

Study Overview
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Brief Summary
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The purpose of this study is to find the adequate additional bronchial cuff volume after achievement of air-tight seal, that can achieve blood-tight seal(preventing leakage of blood through cuff) in double lumen tube

Conditions
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Preventing Blood Leakage of Bronchial Cuff

Intervention / Treatment
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* Procedure: 39 Fr double lumen tube group
* Procedure: 37 Fr double lumen tube group
* Procedure: 35 Fr double lumen tube group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing thoracic surgery under left lower decubitus position, using left sided double lumen tube patient's left main bronchus size adequate for 35Fr, 37 Fr, 39 Fr double lumen tube Exclusion Criteria: dislocation or great movement of double lumen tube depth

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 85 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: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 39 Fr double lumen group<br>patients are assigned to 35 Fr, 37 Fr, 39 Fr double lumen tube group according to their left main bronchus diameter measured by preoperative chest CT, to minimize difference between main bronchus diameter and bronchial tip diameter of double lumen tube | Procedure: 39 Fr double lumen tube group<br>* additional bronchial cuff volume is decided according to up-and-down biased coin design sequential method, by incremental volume of 0.1 ml<br>|
| Experimental: 37 Fr double lumen group<br>patients are assigned to 35 Fr, 37 Fr, 39 Fr double lumen tube group according to their left main bronchus diameter measured by preoperative chest CT, to minimize difference between main bronchus diameter and bronchial tip diameter of double lumen tube | Procedure: 37 Fr double lumen tube group<br>* additional bronchial cuff volume is decided according to up-and-down biased coin design sequential method, by incremental volume of 0.1 ml<br>|
| Experimental: 35 Fr double lumen tube group<br>patients are assigned to 35 Fr, 37 Fr, 39 Fr double lumen tube group according to their left main bronchus diameter measured by preoperative chest CT, to minimize difference between main bronchus diameter and bronchial tip diameter of double lumen tube | Procedure: 35 Fr double lumen tube group<br>* additional bronchial cuff volume is decided according to up-and-down biased coin design sequential method, by incremental volume of 0.1 ml<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| leakage of autologus blood through bronchial cuff |  | 10, 20, 30 minutes after dripping of blood around bronchial cuff | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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bronchial cuff, double lumen tube, blood tight seal