Bispectral Index Throughout Esophageal Cancer Operation

Study Overview
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Brief Summary
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The investigators try to conduct a study to assess the impact of changing patients' lateral decubitus position on BIS readings during esophageal cancer operation. Also, the investigators evaluate the effects of one-lung ventilation and total lung ventilation on BIS value with inhalation agent.

Detailed Description
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Bispectral index (BIS) was developed to monitor a patient's level of consciousness under general anesthesia. Several factors have been found to alter BIS readings without affecting the depth of anesthesia.Changing a patient's position (head up and head down) significantly affects the BIS values, which might affect the interpretation of anesthetic depth. During esophageal cancer surgery, there were several factors which could affect to BIS values.First, the surgical positions are consisted with supine and lateral decubitus position more than 1 h. Thus, the investigators compare the BIS value of both side on supine and lateral decubitus position by both side approach. Second, the one lung ventilation was applied for surgical filed. It alters the oxygenation and the cerebral flow. Because of these effects, the BIS monitoring can differ by the period of surgery. Thus, in this study, the BIS value of both side monitor throughout the surgery.

Official Title
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Which Bispectral Index Score is Reliable Throughout Esophageal Cancer Operation?

Conditions
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Esophageal Cancer

Intervention / Treatment
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* Device: BIS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: the patients who are planned the esophageal cancer operation Exclusion Criteria: patient who has dermatitis patient who refuse to participate in this study

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 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: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: BIS group<br>Patients who received the esophageal surgery | Device: BIS<br>* All patients applied BIS on both side (Left and Right)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Bispectral index score | The difference of both side BIS value on lateral decubitus position | after lateral decubitus position 5 mins, 10 mins, 20 mins, 30 mins | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the asymmetry of BIS | The difference of BIS on supine position | after supine position 5 mins, 10 mins, 20 mins, 30 mins | 
| oxygenation and BIS | the effects of arterial blood gas analysis (O2 mmH2O and CO2 mmH2O) on BIS | intraoperative | 
| The changes of BIS | the difference of BIS divided to 3 BIS level ( <40,40-60,>60) | intraoperative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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bispectral index, lateral decubitus position, one lung ventilation