Compare a New Method and Formula as a Guide for the Intubation of a Left-sided Double-lumen Tube

Study Overview
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Brief Summary
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One-lung ventilation (OLV) is required for the most of thoracic surgery to facilitate surgical visualization by collapsing the lung. The double-lumen tube (DLT) is the commonly used device for OLV. The objective of this study was to compare the accuracy of the distances between vocal cords to carina of trachea and formula base on patient's height as a guide for the intubation of a Left-sided Double-lumen tube

Detailed Description
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In previous study, investigators found that the distances between vocal cords to carina of trachea was a useful predictive method for the intubation of a Left-sided Double-lumen tube. However in some hospitals preoperative chest CT scans not contain the vocal cords slice. So in this study investigators will compare the accuracy of the distances between the midpoint of the thyroid cartilage to suprasternal notch base on body surface measurement add the distance between suprasternal notch to carina of trachea according to chest CT and formula base on patient's height as a guide for the intubation of a Left-sided Double-lumen tube.

Official Title
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Compare the Accuracy of the Distances Between the Midpoint of the Thyroid Cartilage to Suprasternal Notch Base on Body Surface Measurement Add the Distance Between Suprasternal Notch to Carina of Trachea According to Chest CT and Formula Base on Patient's Height as a Guide for the Intubation of a Left-sided Double-lumen Tube

Conditions
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Therapeutic Procedural Complication

Intervention / Treatment
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* Other: Measurement
* Other: Formula


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients undergoing elective left side thoracic surgery Requiring a Uniblocker or DLT for one-lung ventilation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Measurement<br>The distances between the midpoint of the thyroid cartilage to suprasternal notch base on body surface measurement add the distance between suprasternal notch to carina of trachea according to chest CT. | Other: Measurement<br>* The distances between the midpoint of the thyroid cartilage to suprasternal notch base on body surface measurement add the distance between suprasternal notch to carina of trachea according to chest CT<br>|
| Formula<br>The formula base on patient's height as a guide for the intubation of a Left-sided Double-lumen tube. The depth of intubation = 0.1977* height-4.2423 | Other: Formula<br>* The formula base on patient's height as a guide for the intubation of a Left-sided Double-lumen tube<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of the injuries of bronchi and carina | The degree of bronchi and carina injuries: 1 clear; 2 a few petechiae; 3coalesced petechiae, hemorrhage, or ecchymosis; 4 erosion | 1-3days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of dislodgement | The incidence of dislodgement after repositioning | 1 day | 
| The intubation time | The intubation time (IT) was defined as the time from the anesthesiologist inserted the video laryngoscope between the teeth of patients until the double lumen-tube at the optimal position checked by Fiberoptic bronchoscopy | 1-5min |