Axillary Plexus Block in a High Resolution MRI

Study Overview
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Brief Summary
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Background and aims: Magnetic resonance imaging (MRI) has proved beneficial for presenting anatomy for regional anaesthesia and to demonstrate spread of local anaesthetic. A new axillary plexus block with a triple injection (1), combining a short axillary catheter method with a transarterial axillary block, is now being evaluated with a 3 Tesla MRI. In this study, the investigators are investigating MR visualisation of three different block techniques and compare the clinical efficacy of the techniques, with the MR findings. Patients & Methods: After obtaining approval of the protocol from the regional ethical committee, 3 x 15 adult patients, scheduled for hand surgery, were included in a randomised, blinded prospective study.

Detailed Description
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After obtaining approval of the protocol from the regional ethical committee, 3 x 15 adult patients, scheduled for hand surgery, were included in a randomised, blinded prospective study. In all patients a short axillary plexus catheter is positioned close to the median nerve using nerve stimulator. Technique 1 = 40 ml in catheter Technique 2 = 30 ml behind and 10 ml in front of the brachial artery (BA) Technique 3 = 20 ml behind, 10ml in front of the BA and 10 ml in catheter Clinical High Field MRI (3T) scanner has simplified the recognition of brachial plexus nerves in the axilla. After injection of local anaesthetic (LA), the identification of the nerve structures is nevertheless difficult. When all nerves are surrounded of LA in the axilla (MRI), it seems to be associated with a clinical complete brachial plexus block

Official Title
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Axillary Plexus Block in a High Resolution MRI

Conditions
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Nerve Block, Magnetic Resonance Imaging

Intervention / Treatment
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* Procedure: Active Comparator: Arm 1: catheter injection
* Procedure: Active Comparator: Arm 2: transarterial injection
* Procedure: Active Comparator: Arm 3: catheter and transarterial injection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients scheduled for hand surgery ASA 1 - 2 Weight from 50 - 95 kg MR compatible, suitable Exclusion Criteria: Neurologic deficit Reaction to LA

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Arm 1: catheter injection<br>40 ml of LA through the catheter | Procedure: Active Comparator: Arm 1: catheter injection<br> <br> |
| Active Comparator: Arm 2: transarterial injection<br>30 ml deep and 10 ml superficial to the artery | Procedure: Active Comparator: Arm 2: transarterial injection<br> <br> |
| Active Comparator: Arm 3: catheter and transarterial injection<br>20 + 10 ml transarterial block and 10 ml through the catheter | Procedure: Active Comparator: Arm 3: catheter and transarterial injection<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical efficacy of the blocks used compared with MRI findings |  | One year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Peripheral Nerves, Axillary Block, MRI