Patient Positioning on Supraclavicular Nerve Block

Study Overview
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Brief Summary
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Blockade of the brachial plexus using a supraclavicular approach provides excellent anesthesia for upper extremity surgery. The most serious complication specific to this block is pneumothorax. Subsequent modifications of this block including the use of ultrasound have lowered the risk from 6% to <1%. Case reports remain and authors have described certain factors and strategies to reduce this risk. Most texts and journals describe the patient in a supine or semi-sitting position during the block. At the investigators institution the investigators perform the block in a semi-sitting position to facilitate needle tip visibility with ultrasound. The investigators plan to obtain ultrasound anatomic measurements in three different positions (supine, semi-sitting, sitting) using patients consented for supraclavicular nerve blocks.

Conditions
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Nerve Block

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: all patients, 18 y/o to 65 y/o, who are scheduled to receive an ultrasound- guided supraclavicular nerve block Exclusion Criteria: patient refusal to be included in the study, the presence of language barrier that inhibits proper communication with the patient, contraindications to regional anesthesia (local infection, severe pulmonary disease, or preexisting neuropathy) history of allergy to amide local anesthetics or narcotics the presence of a progressive neurological deficit history of hepatorenal insufficiency the presence of a coagulopathy or infection pregnancy a history of psychiatric disorder inability to follow study protocol

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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 |
| --- | --- |
| Sitting Position (head of bed 90 degrees)<br>Ultrasound measurements will be performed. A= skin to the pleura at the level lateral to the subclavian artery, B= skin to center of the subclavian artery, C= skin to first rib, D= skin to corner pocket | |
| Semi-sitting position (45 degrees)<br>Ultrasound measurements will be performed. A= skin to the pleura at the level lateral to the subclavian artery, B= skin to center of the subclavian artery, C= skin to first rib, D= skin to corner pocket | |
| Supine position<br>Ultrasound measurements will be performed. A= skin to the pleura at the level lateral to the subclavian artery, B= skin to center of the subclavian artery, C= skin to first rib, D= skin to corner pocket | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| patient positioning | Ultrasound measurements will be made at three different positions: Sitting, semi-sitting, and supine. The ultrasound measurements include A= skin to the pleura at the level lateral to the subclavian artery, B= skin to center of the subclavian artery, C= skin to first rib, D= skin to corner pocket | Postoperative Day One | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Supraclavicular Block