Analysis of Spread Level During Thoracic Erector Spinae Block

Study Overview
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Brief Summary
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The primary purpose of this study was to identify the ESPB spread level in the craniocaudal direction when performed at the T2 level. The secondary purpose was to determine the incidence of spread into epidural, paravertebral, intercostal, and intravascular injections with ESPB

Detailed Description
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The ESPB requires ultrasound guidance which enables visible local anesthetic spread underneath the erector spinae muscles. The spinalis, longissimus thoracis, and iliocostalis muscles comprise the ES muscles, which run vertically along both sides of the vertebral column from the sacrum up to the skull base. The ESPB can be performed in the cervical, thoracic, and lumbar regions. Among them, upper or mid thoracic ESPB has been used more widely compared to cervical and lumbar regions. Previous cadaveric studies on the ESPB at the T5 level using computed tomography (CT) reconstruction or direct dissection demonstrated the extensive craniocaudal distribution of methylene blue ranging from T1 to T8 vertebral segments deep to the ES muscles and variable involvement of epidural, paravertebral, and intercostal spaces. The ESPB performed at the T2 level of the cadaver demonstrated an injected dye distribution ranging from C4 to T10. Also, 36% of cadavers showed the spread of an injected dye to the ventral, dorsal ramus, paravertebral space, and even the contralateral side. The exact mechanism of action of ESPB remains unclear. A recent study suggested that the analgesic effect of ESPB could be obtained by blocking the ventral and dorsal ramus of the spinal nerves by passing through the costotransverse foramen. However, in clinical practice, we can encounter highly variable clinical outcomes or sensory block after the ESPB. The study of the physical spread of the injected agent can be used to predict the clinical result and elucidate the possible mechanism of action of ESPB.

Official Title
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Comparison of the Spread Level During Thoracic Erector Spinae Plane Block Using Two Volumes of Local Anesthetics

Conditions
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Pain, Radiculopathy, Cervical

Intervention / Treatment
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* Procedure: Erector spinae plane block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: cervical facet joint arthrosis cervical foraminal stenosis cervical herniated intervertebral disc myofascial pain syndrome of upper back muscle Exclusion Criteria: allergy to local anesthetics or contrast medium pregnancy prior history of cervical spine surgery coagulation abnormality

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 |
| --- | --- |
| Experimental: 10 ml ESPB group<br>ESPB group using 10 ml mixture of local anesthetics and contrast medium using ultrasound and fluoroscopy | Procedure: Erector spinae plane block<br>* fascial plane injection using ultrasound and fluoroscopic guidance<br>|
| Experimental: 20 ml ESPB group<br>ESPB group using 20 ml mixture of local anesthetics and contrast medium using ultrasound and fluoroscopy | Procedure: Erector spinae plane block<br>* fascial plane injection using ultrasound and fluoroscopic guidance<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| spread level in the cranio-caudal direction | fluoroscopic contrast medium spread level in the cranio-caudal direction | Baseline, 5 minutes after erector spinae plane block | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participant showing epidural spread | Number of participant showing epidural spread by analysis of fluoroscopic image | baseline, 5 minute after erector spinae plane block | 
| Number of participant showing intercostal spread | Number of participant showing intercostal spread by analysis of fluoroscopic image | baseline, 5 minute after erector spinae plane block | 
| Number of participant showing paravertebral spread | Number of participant showing paravertebral spread by analysis of fluorosocpic image | baseline, 5 minute after erector spinae plane block | 
| Number of participant showing intravascular spread | Number of participants showing intravascular spread by analysis of fluoroscopic image | baseline, 5 minute after erector spinae plane block |