Ultrasound-guided Intermediate Cervical Plexus Block

Study Overview
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Brief Summary
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The investigators test with the present study design, whether an ultrasound-guided blockade of the cervical plexus in combination with an additional application of local anesthetic to the superficial cervical ansa (facial nerve: cervical branch) leads to an improved quality of anesthesia.

Detailed Description
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The innervation of the neck area is complex and includes cranial nerve (innervation of the vessel wall (IX,X) and of the neck muscles (VII,XI)), as well as the cervical plexus and brachial plexus. This is a major cause of insufficient anesthesia quality during carotid endarterectomies. The investigators test with the present prospective study design, whether an ultrasound-guided blockade of the cervical plexus in combination with an additional application of local anesthetic to the superficial cervical ansa (facial nerve: cervical branch) leads to an improved quality of anesthesia.

Official Title
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Ultrasound-guided Intermediate Cervical Plexus Block for Carotid Endarterectomies

Conditions
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Internal Carotid Artery Stenosis

Intervention / Treatment
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* Other: cervical plexus block
* Other: facial nerve block
* Other: perivascular block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: internal carotid stenosis: open surgical revascularization age over 18 years written informed consent Exclusion Criteria: allergy (local anesthetics) pregnancy participation in other studies drug addiction non-cooperative patients

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: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: with perivascular block<br>1. ultrasound-guided intermediate cervical plexus block (20ml ropivacaine 0.75%) 2. facial nerve block (cervical branch) (5ml prilocaine 1%) 3. perivascular block (5ml prilocaine 1%) | Other: cervical plexus block<br>* ultrasound-guided application of 20ml ropivacaine 0.75%<br>* Other names: cervical plexus anesthesia;Other: facial nerve block<br>* ultrasound-guided application of 5ml prilocaine 1%<br>* Other names: facial nerve anesthesia;Other: perivascular block<br>* ultrasound-guided application of 5ml prilocaine 1%<br>* Other names: perivascular infiltration;|
| Experimental: without perivascular block<br>1. ultrasound-guided intermediate cervical plexus block (20ml ropivacaine 0.75%) 2. facial nerve block (cervical branch) (5ml prilocaine 1%) | Other: cervical plexus block<br>* ultrasound-guided application of 20ml ropivacaine 0.75%<br>* Other names: cervical plexus anesthesia;Other: facial nerve block<br>* ultrasound-guided application of 5ml prilocaine 1%<br>* Other names: facial nerve anesthesia;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Local Anesthetic Supplementation (Frequency) | number of participants who need supplementation of prilocaine 1% by the surgeon (%) | intraoperatively | 
| Local Anesthetic Supplementation (Volume) | volume of prilocaine 1% supplemented by the surgeon (ml) | intraoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hoarseness | number of participants who experienced side effects: hoarseness | intraoperatively | 
| Cough | number of participants who experienced side effects: cough | intraoperatively | 
| Dysphagia | number of participants who experienced side effects: dysphagia | intraoperatively |