Displacement Between PVC and Silicon DLT

Study Overview
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Brief Summary
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The purpose of this study is to compare difference of displacement between Polyvinyl Chloride(PVC) and Silicon double-lumen endobronchial tubes(DLTs) during changing position from supine to lateral in thoracic surgery.

Detailed Description
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Lung isolation and differential lung ventilation, resulting in collapse of operative lung and ventilation of non-operating lung (one lung ventilation; OLV) are essential for thoracic surgery in lung, esophagus and thoracic aorta. DLT, consisted of tracheal and bronchial lumens, is commonly used to perform differential lung ventilation. The correct position of each lumen in trachea and main bronchus is essential for successful OLV. However, DLT displacement occurs commonly while patients are changed position from the supine to the lateral. The deleterious consequences of a malpositioned DLT can be substantial, even life-threatening including severe hypoxemia. Considering displacement of DLT during position change and surgical traction, previous studies recommended endobronchial cuff of DLT should be positioned at 0.5cm below the tracheal carina when using left-sided DLT. However, it is based on the data from several research conducted by PVC DLT. These days, Silicon DLT, different in material from PVC DLT, is also widely used in clinical practice. Silicon DLT is different in not only position of ballon but also distance of each lumen. Furthermore,there are no identified studies about the displacement of silicon DLT during patient position change in thoracic surgery. Therefore, it is necessary to measure the movement of silicon DLT during positional change from supine to lateral for finding the proper positioning of DLT. The investigators compare the difference of displacement between PVC DLT and silicon DLT distance during positional change from supine to lateral by fiberotic bronchoscope. And the investigators try to find proper position of PVC and silicon DLT, respectively, to perform safe and successful OLV during thoracic surgery.

Official Title
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Comparison of Displacement Between Polyvinyl Chloride(PVC) and Silicon Double-Lumen Endobronchial Tubes(DLT) During Change of Position

Conditions
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Endotracheal Tube Wrongly Placed During Anesthetic Procedure, Surgical Procedure, Unspecified

Intervention / Treatment
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* Device: PVC DLT
* Device: silicon DLT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient required differential lung ventilation in elective thoracic surgery American society of Anesthesiologist physical status(ASA PS) 1 3 Exclusion Criteria: emergency surgery, difficult intubation, poor lung function to accomplish OLV during surgery

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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 |
| --- | --- |
| Active Comparator: PVC DLT<br>After the induction of general anesthesia, a left sided PVC DLT was placed by the anesthesiologist using direct laryngoscopy. Tube position was confirmed with fiberotic bronchoscope. The first set of measurements tracheal distance(from tracheal carina to proximal tip of DLT) and bronchial distance(from bronchial carina to distal tip of DLT) measured by bronchoscope is taken in supine position . The second set of measurements is taken in lateral position after position change. The displacement of PVC DLT is calculated from difference in tracheal distance between supine and lateral position. | Device: PVC DLT<br>* PVC DLT is type of double lumen tube that is composed of PVC<br>* Other names: PVC double-lumen tube;|
| Active Comparator: silicon DLT<br>After the induction of general anesthesia, a left sided silicon DLT was placed by the anesthesiologist using direct laryngoscopy. Tube position was confirmed with fiberotic bronchoscope. The first set of measurements tracheal distance(from tracheal carina to proximal tip of DLT) and bronchial distance(from bronchial carina to distal tip of DLT) measured by bronchoscope is taken in supine position . The second set of measurements is taken in lateral position after position change. The displacement of silicon DLT is calculated from difference in tracheal distance between supine and lateral position. | Device: silicon DLT<br>* silicon DLT is type of double lumen tube that is composed of silicon<br>* Other names: silicon double-lumen tube;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the Incidence of Clinically Significant Displacement of DLTs During Change of Patient Position | The tracheal distance was defined as the distance between the distal tip of the tracheal lumen and tracheal carina whereas the bronchial distance was defined as that between the bronchial carina and distal tip of endobronchial lumen. The displacement of DLT was determined by changes in tracheal and bronchial distances, obtained by subtracting supine measurements from lateral measurements and subtracting measurements at start of surgery from measurements at the end of surgery, respectively. Clinically significant displacement was defined when the DLT was deviated by more than 10 mm from the initial correct position, regardless of the direction of displacement. | from supine to lateral decubitus position during surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the Incidence of Critical Malposition of DLTs | The displacement of DLT was determined by changes in tracheal and bronchial distances, obtained by subtracting supine measurements from lateral measurements and subtracting measurements at start of surgery from measurements at the end of surgery, respectively. The critical malposition was defined when the DLT was required repostion for successful OLV during position change | from supine to lateral decubitus position | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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one lung ventilation, double lumen endobronchial tube, displacement, Fiberoptic bronchoscope