Comparison Between Costoclavicular and Paracoracoid Ultrasound-guided Infraclavicular Block for Forearm Surgery

Study Overview
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Brief Summary
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The costoclavicular space block technique is a new developed approach of ultrasound-guided infraclavicular brachial plexus block(USG-ICB) in last two years and has not been studied much yet. The paracoracoid approach serves as a standard and traditional method for USG-ICB in clinical practice, easy to learn and perform. The investigators set this parallel controlled dose-finding trial to work out the MEV with 0.5% ropivacaine of both two approaches above for forearm surgery and compare the performance time between them, providing reasonable evidence for clinical choice.

Detailed Description
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The costoclavicular space block technique is a new developed approach of ultrasound-guided infraclavicular brachial plexus block(USG-ICB) in last two years and has not been studied much yet. USG-ICB represents an attractive option for upper-limb surgery at or below the elbow joint with similar success rate and fewer adverse effects compared with ultrasound-guided supraclavicular block. The paracoracoid approach serves as a standard and traditional method for USG-ICB in clinical practice, easy to learn and perform. However, the minimum effective volume(MEV)of this approach has been studied by different investigators with different regional anesthetics or its mixture, and specially, the 95% MEV result of this approach is more than 30ml in all related researches which is still a large volume. According to the investigators' experience in using the costoclavicular space technique for forearm surgery, it usually can get a comparable sensation and motor block effect by no more than 25ml. Recently, there was a clinical randomized control study which compared the costoclavicular and paracoracoid USG-ICB for upper limb surgery using a 35ml-mixture of 1% lidocaine-0.25% bupivacaine with epinephrine 5 ug/ml and came to the conclusions: two groups resulted in similar onset times and no intergroup difference were found in terms of performance time and success rate. However, 35ml is a much larger regional anesthetic volume than what we used in routine brachial plexus block. So, we set this parallel controlled dose-finding trial to work out the MEV with 0.5% ropivacaine of both approaches above for forearm surgery and compare the performance time between them, providing reasonable evidence for clinical choice. Patients enrolled in this study will be assigned to costoclavicular group and paracoracoid group and in each group, the volume of local anesthetic applied to patients start with 30ml, and then decreased by 2.5ml for next patient when the previous block is successful, otherwise increased by 2.5ml when failed,which is also called a staircase up-and-down method usually applied in dose-finding research of nerve block. After certain reflections of the local anesthetic volume sequential line graph, the minimum effective volume could be calculated.

Official Title
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A Randomized Comparison of Minimum Effective Volume With 0.5% Ropivacaine Between Costoclavicular and Paracoracoid Ultrasound-guided Infraclavicular Block for Forearm Surgery

Conditions
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Brachial Plexus Block

Intervention / Treatment
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* Procedure: costoclavicular infraclavicular block
* Procedure: paracoracoid infraclavicular block
* Device: Ultrasound
* Drug: Ropivacaine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA status 1 to 3 BMI 20-35 Scheduled for surgery at elbow joint or below Exclusion Criteria: Inability to consent to the study Preexisting neuropathy,coagulopathy,COPD Hepatic or renal failure Allergy to local anesthetics Pregnancy Prior surgery in infraclavicular region

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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
Interventional Model Description: costoclavicular group and paracoracoid group
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: costoclavicular group<br>patients in this group are assigned to receive ultrasound-guided costoclavicular infraclavicular block with 0.5% ropivacaine for upper limb surgery at elbow joint and below | Procedure: costoclavicular infraclavicular block<br>* Infraclavicular brachial plexus block will be performed through new costoclavicular space approach under realtime ultrasound guidance with 0.5% ropivacaine<br>Device: Ultrasound<br>* All the nerve blocks will be performed under realtime ultrasound guidance<br>Drug: Ropivacaine<br>* 0.5% ropivacaine will be used for the brachial plexus block in both groups.<br>|
| Other: paracoracoid group<br>patients in this group are assigned to receive ultrasound-guided paracoracoid infraclavicular block with 0.5% ropivacaine for upper limb surgery at elbow joint and below | Procedure: paracoracoid infraclavicular block<br>* Infraclavicular brachial plexus block will be performed through traditional paracoracoid approach under realtime ultrasound guidance with 0.5% ropivacaine<br>Device: Ultrasound<br>* All the nerve blocks will be performed under realtime ultrasound guidance<br>Drug: Ropivacaine<br>* 0.5% ropivacaine will be used for the brachial plexus block in both groups.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| MEV | minimum effective volume regional anesthetic need for a successful infraclavicular block | The anesthesia effect of the block with a specified volume fo local anesthetic will be assessed at 30 min after the nerve block finished, the MEV will be calculated after all. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| performance time | time needed for the block performance | from the time point when ultrasound probe touches with patients' skin to the end when local anesthetic is injected through the needle, which is usually up to ten minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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costoclavicular, paracoracoid, brachial plexus