Ultrasound Guided Intermediate Cervical Plexus Block and Additional Perivascular Local Anesthetic Infiltration

Study Overview
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Brief Summary
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For ultrasound guided intermediate cervical plexus block this randomized comparison is testing the hypothesis, that an additional perivascular infiltration is associated with increased block quality.

Detailed Description
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The innervation of the neck is complex and involves the cervical and the brachial plexus as well as cranial nerves. So is the wall of the carotid arteries innervated by vagal and glossopharyngeal nerve as well as the sympathetic trunk. When carotid surgery was performed under regional anesthesia, so additional infiltration of local anesthetic by the surgeon was common, particularly during preparation of the carotid arteries. Introduction of ultrasound guidance made it possible to guide the needle directly to the vascular wall. But this procedure is considered very demanding, because of guiding the needle in an anatomical region with artifacts (because of calcification), sudden movements (e.g. because of swallowing) and compromised coagulation (antithrombotic medication). On the other side there are no clinical data proving the benefit of an additional perivascular infiltration with local anesthetic. Therefore, this investigation is testing the hypothesis, that an additional perivascular infiltration is associated with increased block quality.

Official Title
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Ultrasound Guided Intermediate Cervical Plexus Block -Randomized Evaluation Concerning the Significance of Additional Perivascular Local Anesthetic Infiltration

Conditions
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Carotid Stenosis

Intervention / Treatment
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* Drug: intermediate cervical plexus block ropivacaine
* Drug: pericarotidal infiltration (active comparator) ropivacaine
* Drug: jugular infiltration prilocaine
* Drug: pericarotidal infiltration (placebo comparator) saline


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: carotid surgery (symptomatic and asymptomatic carotid stenosis) adult patients (18 years or older) ASA-risk-groups I-IV informed consent Exclusion Criteria: drug allergy: local anesthetics pregnancy, lactation period participation in other studies addiction to drugs or alcohol non-cooperative patients no approval to regional anesthesia

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: ropivacaine<br>Ultrasound guided intermediate cervical plexus block: 20ml ropivacaine 0.75%. Ultrasound guided perivascular/pericarotidal infiltration: 5ml ropivacaine 0.75%. | Drug: intermediate cervical plexus block ropivacaine<br>* 20ml ultrasound guided intermediate cervical plexus block.<br>Drug: pericarotidal infiltration (active comparator) ropivacaine<br>* 5ml ropivacaine 0.75% (active comparator): pericarotidal infiltration.<br>Drug: jugular infiltration prilocaine<br>* 5ml prilocaine 1% jugular infiltration for wound drainage.<br>|
| Placebo Comparator: saline<br>Ultrasound guided intermediate cervical plexus block: 20ml ropivacaine 0.75%. Ultrasound guided perivascular/pericarotidal infiltration: 5ml saline 0.9%. | Drug: intermediate cervical plexus block ropivacaine<br>* 20ml ultrasound guided intermediate cervical plexus block.<br>Drug: jugular infiltration prilocaine<br>* 5ml prilocaine 1% jugular infiltration for wound drainage.<br>Drug: pericarotidal infiltration (placebo comparator) saline<br>* 5ml saline 0.9% (placebo comparator): pericarotidal infiltration.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Patients With Required Supplementation of Local Anesthetic by Surgeon |  | during the intraoperative period | 
| Amount (ml) of Local Anesthetic Supplemented by Surgeon |  | during the intraoperative period | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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cervical plexus, regional anesthesia, ultrasound, carotid surgery