Dual Guidance in Regional Anesthesia

Study Overview
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Brief Summary
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Regional anaesthesia is a frequently used procedure. Currently, blockades are increasingly carried out without nerve stimulation. The risk of nerve lesion is about 3 %. Industrial efforts frequently referred to ultrasound optimisation of the regional anaesthesia cannula. In order to optimise patient safety, the benefit of both procedures (stimulation and ultrasound) should be combined and both procedures optimised. In this study, the influence of the needle electrode size on the stimulability of the nerve ischiadicus should be determined.

Detailed Description
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There are various methods of performing regional anesthesia. In recent years, the focus has been on ultrasound-supported regional anaesthesia, and the stimulation methods that were often used in the past were no longer used or used less frequently. The combination of both methods may be an additional safety aspect and can contribute to an improved blocking quality. In addition to the best possible ultrasound quality, an optimal stimulation quality is also required. The investigators plan to carry out dual-guidance blockages of the ischiadic nerve with various regional anaesthesia needles (manufacturer of the used needles: Pajunk Medical Produkte GmbH, Geisingen, Germany; Teleflex Medical GmbH, Kernen, Germany). All regional anaesthesia cannulae are approved for the planned blockades of humans in Germany.

Official Title
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Dual Guidance in Regional Anesthesia - Prospective Randomized Study of Needle-nerve Distance in Different Cannulas for Regional Nerve Blockade

Conditions
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Anesthesia, Local, Anesthesia, Anesthesia; Adverse Effect

Intervention / Treatment
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* Procedure: Regional Anesthesia Touhy
* Procedure: Regional Anesthesia Facet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Presence of the written declaration of consent Age of at least 18 years No participation in another intervention study during participation Exclusion Criteria: present contraindication for the application of regional anesthesia and nerve stimulation Cardiac pacemaker/AICD (Automated internal cardioverter defibrillator) carrier Known allergies to used medicines Patients under 18 years of age Ineligible patients Missing consent Pregnancy/nursing patients Classification of patients into class 4 or higher status according to the American Society of Anesthesiologists Existing nerve damage in the target area Medically treated diabetes mellitus, alcohol abuse or alcohol abuse in the patient's history (using AUDIT) Visibility score of the nerve of 3 or more Participation in another intervention study during participation Accommodation in an institution on the basis of a court or administrative order

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
Interventional Model Description: The selection of the puncture cannula for regional anaesthesia is not up to the performing anaesthetist, as is usual in the clinical standard, but is made randomly on the basis of a random list. The blockade is carried out by two anaesthetists experienced in regional anaesthesia, who have the principle of dual control. The ultrasound image acquired during the blockade is recorded in the form of an ultrasound video for subsequent evaluation. The recorded ultrasound videos are stored pseudonymously on the server of the Klinik für Anästhesiologie m. S. operativ Intensivmedizin reported to the data protection department.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Tuohy<br>After a careful disinfection of the puncture site, under sterile conditions and under ultrasonographic control with the application of nerve stimulation (settings: stimulation current primary 2.0 mA with stepwise reduction over 1.0 mA to 0.5 mA, pulse width 0.1 ms, pulse frequency 2 Hz) of the N. ischiadicus blocked by 20 ml ropivacaine 0.75 %. (electrical nerve stimulation and ultrasound) If no motor response can be triggered by stimulation, the closest possible needle-nerve distance is generated at a pulse strength of 1mA and regional anesthesia is performed. (protective nerve stimulation) Subsequently, the transplantation into the supine position and the further procedure specific to the operation (use of other regional procedures in combination or general anaesthesia). A tuohy needle is used. | Procedure: Regional Anesthesia Touhy<br>* The patients receive the planned anaesthesia procedure according to the procedure to be performed. Only nerve blockages are carried out, which are considered to be analgesic useful for the planned operations on the basis of typical nerve courses. A touhy cannula is used.<br>|
| Active Comparator: Facet<br>After a careful disinfection of the puncture site, under sterile conditions and under ultrasonographic control with the application of nerve stimulation (settings: stimulation current primary 2.0 mA with stepwise reduction over 1.0 mA to 0.5 mA, pulse width 0.1 ms, pulse frequency 2 Hz) of the N. ischiadicus blocked by 20 ml ropivacaine 0.75 %. (electrical nerve stimulation and ultrasound) If no motor response can be triggered by stimulation, the closest possible needle-nerve distance is generated at a pulse strength of 1mA and regional anesthesia is performed. (protective nerve stimulation) Subsequently, the transplantation into the supine position and the further procedure specific to the operation (use of other regional procedures in combination or general anaesthesia). A facet needle is used. | Procedure: Regional Anesthesia Facet<br>* The patients receive the planned anaesthesia procedure according to the procedure to be performed. Only nerve blockages are carried out, which are considered to be analgesic useful for the planned operations on the basis of typical nerve courses. A facet cannula is used.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ultrasound distance | Ultrasound-based measurement of needle-nerve distance during the application of the regional anesthesia of the N. ischiadicus during infragluteal access. | duration of blockade, an average of 15 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visibility_1 | Ultrasound visibility of needle | duration of blockade, an average of 15 minutes | 
| Visibility_2 | Ultrasound visibility of nerve | duration of blockade, an average of 15 minutes | 
| Impedance | Impedance measured by nerve stimulator while progressing the needle | duration of blockade, an average of 15 minutes | 
| Effect_motor | Effectiveness of the motor blockade measured by possible movement of the foot | duration of surgery and recovery unit, an average of 120 minutes | 
| Effect_sensoric | Effectiveness of the blockade measured by temperature sensibility testing on the food | duration of surgery and recovery unit, an average of 120 minutes |