Effect of Lateral Positioning on Bronchial Cuff Pressure of Left-sided Double-lumen Endotracheal Tube During Thoracic Surgery

Study Overview
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Brief Summary
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The investigators evaluate the effect of postural change on the bronchial cuff pressure (BCP) of double-lumen endotracheal tube (DLT) in patients undergoing thoracic surgery, by observing the pressure of the bronchial cuff before and after lateral decubitus positioning.

Detailed Description
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It is essential to maintain proper cuff pressure in the endotracheal tube (ETT) when placing the ETT in the trachea in patients undergoing general anesthesia. Most of the literature recommend maintaining a pressure of 20-30 cmH2O to prevent cuff-related complications such as micro-aspiration or airway trauma. Proper pressure is also important for DLTs used in thoracic surgery. Furthermore, the cuff pressure of the ETT can change during the patient's positional changes. All things considered, we hypothesized that the change from supine to lateral decubitus position, which is essential for thoracic surgery would affect the BCP of the DLT.

Official Title
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Effect of Lateral Positioning on Bronchial Cuff Pressure of Left-sided Double-lumen Endotracheal Tube During Thoracic Surgery: a Prospective Observational Study

Conditions
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Lung Cancer, Pneumothorax

Intervention / Treatment
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* Behavioral: Lateral decubitus positioning
* Device: Cuff-manometer


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiologists (ASA) physical status 1 or 2 Elective lung surgery requiring lateral decubitus positioning and one-lung ventilation using left-sided DLT Exclusion Criteria: Patients requiring a right-sided DLT. Patients with an intraluminal lesion in the left mainstem bronchus (LMB). Patients with an anatomical problem in the tracheobronchial tree. Patients with impaired lung such as chronic obstructive pulmonary disease. Patients who refused to participate in this study.

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

| Intervention/Treatment |
| --- |
|Behavioral: Lateral decubitus positioning|After the DLT intubation, the patient is placed in lateral decubitus position|
|Device: Cuff-manometer|The pressure of the bronchial cuff should be measured with cuff-manometer in supine position, and then measurement should be repeated after lateral positioning.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of the maximum bronchial cuff pressure (BCP) which does not exceed 40 cmH2O with no air leak from supine to lateral decubitus position | A cuff-manometer will be connected to the valve of the pilot balloon of bronchial cuff via a three-way stopcock. And then, the BCP will be assessed, while inflating the cuff with air in 0.5 ml increments from 0 to 3.0 ml. If the BCP exceeds 40 cmH2O during expansion by increasing 0.5 ml from 0 to 3.0 ml, we will stop inflating the bronchial cuff with air and record the bronchial cuff volume (BCV) and BCP up to the last numerical value. During the pressure measurement, air leak or seal around the bronchial cuff will be assessed at each time point when inflating the cuff in 0.5 ml increments. | 1. In supine position, 2 minutes after the completion of confirming the double-lumen endotracheal tube (DLT) position via fiberoptic bronchoscope (FOB) 2. In lateral position, 2 minutes after the completion of confirming the DLT position via FOB | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of the patients whose maximum BCP exceed 40 cmH2O after lateral positioning |  | 1. In supine position, 2 minutes after the completion of confirming the DLT position via FOB 2. In lateral position, 2 minutes after the completion of confirming the DLT position via FOB | 
| The minimum BCV that is the smallest bronchial cuff volume without air leakage |  | 1. In supine position, 2 minutes after the completion of confirming the DLT position via FOB 2. In lateral position, 2 minutes after the completion of confirming the DLT position via FOB | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Double-lumen endotracheal tube, Cuff pressure