Optic Nerve Sheath Diameter Difference

Study Overview
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Brief Summary
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Intracranial pressure is measured indirectly using optic nerve sheath diameter with ultrasound. It is reported that epidural pressure varies according to different posture ( lateral decubitus vs. sitting position). This study is designed to measure the optic nerve sheath diameter in lateral decubitus and sitting position, respectively.

Detailed Description
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According to previous study, injection of different volume of local anesthetics (1.0 ml/kg vs. 1.5 ml/kg) during caudal anesthesia, high volume of local anesthetics resulted in significant increase of intracranial pressure (ICP). Increase of ICP can reduce regional cerebral flow and oxygen saturation causing the safety of patients. In addition, increase of ICP can result in headache, syncope, and transient loss of visual acuity. Although it is very invasive method, ICP can be measured directly at the brain parenchyme. Among methods to measure the ICP indirectly, measurement of optic nerve sheath diameter using ultrasound is known to reflect the degree of ICP. It is reported that optic nerve sheath diameter increases when higher volume of medication is injected during epidural anesthesia. Previous reports showed that epidural pressure varies according to different posture. When epidural pressure was measured in patients of spinal stenosis, lumbar flexion showed lower epidural pressure than epidural pressure of lumbar extension. In addition, when epidural pressure was measured in the sitting position, it showed lower pressure than pressure of lateral decubitus.

Official Title
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Effect of Different Posture on Optic Nerve Sheath Diameter During Thoracic Epidural Catheterization

Conditions
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Optic Neve Sheath Diameter

Intervention / Treatment
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* Other: thoracic epidural catheterization


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: lung cancer liver cancer stomach cancer pancreas cancer Exclusion Criteria: coagulopathy infection previous spine fusion at thoracic level previous brain surgery

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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: injection under sitting position<br>saline injection under sitting position during thoracic epidural catheterization | Other: thoracic epidural catheterization<br>* thoracic epidural catheterization with different posture<br>|
| Active Comparator: injection under lateral decubitus position<br>saline injection under lateral decubitus position during thoracic epidural catheterization | Other: thoracic epidural catheterization<br>* thoracic epidural catheterization with different posture<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| optic nerve sheath diameter change among 4 time period | optic nerve sheath diameter change among 4 time period using ultrasound | Baseline, 10 minutes, 20 minutes, 40 minutes after the completion of the intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Optic Nerve Sheath Diameter Different Position