Ultrasound Image Study for Ultrasound-assisted Paramedian Spinal Anesthesia

Study Overview
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Brief Summary
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This prospective observational study aimed to obtain ultrasound images for ultrasound-assisted paramedian spinal anesthesia and identify the differences according to sidedness of approach, position and age.

Official Title
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Ultrasound Image Study for Ultrasound-assisted Paramedian Spinal Anesthesia: Difference in Sidedness of Approach, Position and Age

Conditions
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Anesthesia, Spinal, Ultrasonography, Sidedness, Position

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients under 40 or over 60 years of age who require spinal anesthesia for orthopedic surgery, with ASA physical status classification system I, II, III Exclusion Criteria: Patients with contraindication to spinal anesthesia (coagulopathy, local infection, allergy to local anesthetic) Patients with communication difficulties Patient who can not take a sitting or lateral decubitus position (fracture) Patients with a history of spinal surgery Patient with anatomical abnormality of the spine

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 18 ≤ age ≤ 40<br>18 ≤ age ≤ 40 | |
| age ≥ 60<br>age ≥ 60 | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ultrasonic visualization grading at left L3-4, L4-5, L5-S1 interspace and right L3-4, L4-5, L5-S1 interspace in lateral decubitus position and sitting position | Good: Both LFD (ligamentum flavum-dura mater complex) and PLL (posterior longitudinal ligament) are visible Intermediate: Only one of LFD or PLL is visible Poor: LFD and PLL are not visible | Preanesthesia | 
| Distance between the midline and the expected location of needle insertion | Distance between the midline of the vertebrae and the expected location of needle insertion at left L3-4, L4-5, L5-S1 interspace and right L3-4, L4-5, L5-S1 interspace in lateral decubitus position and sitting position | Preanesthesia | 
| Height of LFD through interlaminar space | Height of LFD through interlaminar space visible in ultrasound image at left L3-4, L4-5, L5-S1 interspace and right L3-4, L4-5, L5-S1 interspace in lateral decubitus position and sitting position | Preanesthesia | 
| Depth from skin to LFD | The depth from skin to LFD at left L3-4, L4-5, L5-S1 interspace and right L3-4, L4-5, L5-S1 interspace in lateral decubitus position and sitting position | Preanesthesia | 
| Depth from skin to PLL | The depth from skin to PLL at left L3-4, L4-5, L5-S1 interspace and right L3-4, L4-5, L5-S1 interspace in lateral decubitus position and sitting position | Preanesthesia | 
| Width of the intrathecal space | The distance between the LFD and the PLL at left L3-4, L4-5, L5-S1 interspace and right L3-4, L4-5, L5-S1 interspace in lateral decubitus position and sitting position | Preanesthesia |