Ultrasound Guided Distal Sciatic Nerve Block - a Comparison With Nerve Stimulator Technique
- Conditions
- Other Surgical Procedures
- Interventions
- Device: ultrasound guidanceDevice: nerve stimulation technique
- Registration Number
- NCT01643616
- Lead Sponsor
- Helios Research Center
- Brief Summary
For distal sciatic nerve block this prospective, randomised comparison with ultrasound guided distal subepineural block tested the hypothesis, that intraepineural injection of local anesthetic using nerve stimulation technique is common and associated with high success rate.
- Detailed Description
Classical methods for nerve localization (loss of resistance, cause of paresthesias, nerve stimulation technique)assumed that the target is a close approximation to the nerve, without epineural perforation. Intraneural injections were considered as evitable, with high risk for nerve damages.
Ultrasound guidance provided for the first time a real-time visualization of the spread of local anesthetic. Some recent studies proved, that an intraneural injection using nerve stimulator technique is common and not necessarily accompanied with nerve damages.
In the ultrasound group (group US) the investigators tested the hypothesis, that an intraneural injection of local anesthetic generate a high success rate and a short onset time without clinical apparent nerve damages.
In the nerve-stimulation group (group NS) the investigators tested the hypothesis, that an intraneural injection of local anesthetic is common, and in case of intraneural injection accompanied likewise with high success rate and shorter onset time.
For the sciatic division the investigators tested the hypothesis, that classical methods of nerve localization (nerve-stimulation technique, cause of paresthesias) are not able to avoid epineural perforation.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 250
- elective surgery on the foot or ankle
- tourniquet distal of the knee
- adult patients, 18-75 years old
- ASA-risk-groups I-III (American Society of Anesthesiologists)
- informed consent
- severe coagulopathy
- systemic inflammatory response
- ASA-risk-groups > III (American Society of Anesthesiologists)
- drug allergy: local anesthetics
- pregnancy, lactation period
- participation in other studies
- addiction to drugs or alcohol
- non-cooperative patients
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description group US Prilocaine 1% Ultrasound guided block : 20ml Prilocaine 1% and 10ml Ropivacaine 0.75% (30ml Prilocaine 1% in outpatients) group US Ropivacaine 0.75% Ultrasound guided block : 20ml Prilocaine 1% and 10ml Ropivacaine 0.75% (30ml Prilocaine 1% in outpatients) group US ultrasound guidance Ultrasound guided block : 20ml Prilocaine 1% and 10ml Ropivacaine 0.75% (30ml Prilocaine 1% in outpatients) group NS Prilocaine 1% Nerve stimulation technique: 20ml Prilocaine 1% and 10ml Ropivacaine 0.75% (30ml Prilocaine 1% in outpatients) group NS Ropivacaine 0.75% Nerve stimulation technique: 20ml Prilocaine 1% and 10ml Ropivacaine 0.75% (30ml Prilocaine 1% in outpatients) group NS nerve stimulation technique Nerve stimulation technique: 20ml Prilocaine 1% and 10ml Ropivacaine 0.75% (30ml Prilocaine 1% in outpatients) group US midazolam Ultrasound guided block : 20ml Prilocaine 1% and 10ml Ropivacaine 0.75% (30ml Prilocaine 1% in outpatients) group NS midazolam Nerve stimulation technique: 20ml Prilocaine 1% and 10ml Ropivacaine 0.75% (30ml Prilocaine 1% in outpatients)
- Primary Outcome Measures
Name Time Method Success Rate Without Supplementation within 30-60 minutes after injection of the local anesthetic After injection of local anesthetic a waiting period of 30-60 minutes was defined before completing a failed block.
1. success without supplementation = no additional analgetics or rescue blocks required (success rate without supplementation, outcome measure 1)
2. success with supplementation = analgetics or selective rescue blocks distal of the sciatic division required (success rate without supplementation and additionally all supplemented blocks, outcome measure 3)
3. failed block = change of anesthetic procedure (general, spinal) or rescue blocks proximal of the sciatic divisionTime Until Readiness for Surgery (Minutes) within 60 minutes after injection of the local anesthetic Success Rate With Supplementation later than 30-60 minutes after injection of the local anesthetic After injection of local anesthetic a waiting period of 30-60 minutes was defined before completing a failed block.
1. success without supplementation = no additional analgetics or rescue blocks required (success rate without supplementation, outcome measure 1)
2. success with supplementation = analgetics or selective rescue blocks distal of the sciatic division required (success rate without supplementation and additionally all supplemented blocks, outcome measure 3)
3. failed block = change of anesthetic procedure (general, spinal) or rescue blocks proximal of the sciatic divisionSucces rate with supplementation
- Secondary Outcome Measures
Name Time Method