A Difference in Subclavian Vein Catheterization Between Supine and Lateral Tilt Position - Stage I

Study Overview
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Brief Summary
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Central venous catheterization is widely used for various purposes during surgery. For central venous catheterization, subclavian vein is selected because of the relatively low risk of infection, long-term patency and low patient discomfort. The cross - sectional area of the subclavian vein is an important factor to increase success rate. Several studies have reported that the Trendelenburg position increases the cross-sectional area of the subclavian vein, and the lateral tilt position can change the cross-sectional area of the subclavian vein. However, the impact of lateral tilt position to the cross-sectional area of the subclavian vein is not clear. The ipsilateral position can increase the cross-sectional area of the subclavian vein, and the contralateral position can decrease the cross-sectional area by gravity. In the first stage of this study, we compare the cross-sectional area of subclavian vein using ultrasonography in supine, ipsilateral, and contralateral tilt position.

Official Title
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A Difference in the Cross-section Area of Subclavian Vein Between Supine and Lateral Tilt Position: Its Clinical Impact on Subclavian Venous Catheterization - Stage II

Conditions
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Catheterization, Posture

Intervention / Treatment
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* Procedure: Ipsilateral tilt
* Procedure: Contralateral tilt


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - the patients who receive elective neurosurgical surgery and require central venous catheter Exclusion Criteria: the patients who have puncture site infection the patients who have chemoport, pacemaker in right subclavian vein the patients who had received right mastectomy or right pneumonectomy other contraindications for subclavian venous catheterization (eg. mass, hematoma, vegetation, and anticoagulation)

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 79 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: Diagnostic
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Ipsilateral tilt<br>Measuring the cross-sectional area of right subclavian vein in the 20 degree left tilting posture. | Procedure: Ipsilateral tilt<br>* The operation table will be tilted 20 degrees right laterally.<br>|
| No Intervention: Supine<br>Measuring the cross-sectional area of right subclavian vein in supine position. | |
| Active Comparator: Contralateral tilt<br>Measuring the cross-sectional area of right subclavian vein in the 20 degree left tilting posture. | Procedure: Contralateral tilt<br>* The operation table will be tilted 20 degrees left laterally.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The cross-sectional area of right subclavian vein | The cross-sectional area of right subclavian vein | 1 minutes after position change |