Ultrasound Guided Distal Sciatic Nerve Block - a Comparison With Nerve Stimulator Technique

Other Surgical Procedures Clinical Trial

Official title:

Ultrasound Guided Distal Sciatic Nerve Block - a Randomised Comparison With Nerve Stimulator Technique

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01643616
• Other study ID #: HV 2010 003
• Status: Completed
• Phase: N/A
• First received: July 16, 2012
• Last updated: August 27, 2013
• Start date: November 2010
• Est. completion date: September 2012

Study information

• Verified date: August 2013
• Source: Helios Research Center
• Contact: n/a
• Is FDA regulated: No
• Health authority: Germany: Federal Institute for Drugs and Medical Devices
• Study type: Interventional

Clinical Trial 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.

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 information / eligibility

• Status: Completed
• Enrollment: 250
• Est. completion date: September 2012
• Est. primary completion date: June 2012
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years to 75 Years

Eligibility

Inclusion Criteria:

• 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

Exclusion Criteria:

• 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

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment

Related Conditions & MeSH terms

• Other Surgical Procedures

Intervention

Drug:
• midazolam
Prior to performing the regional anesthesia the investigators administered midazolam as a premedication by mouth (3,75-7,5mg) or intravenously (2-3mg).
• Prilocaine 1%
20ml Prilocaine 1% for distal sciatic nerve block (30ml Prilocaine 1% in outpatients)
• Ropivacaine 0.75%
10ml Ropivacaine 0.75% for distal sciatic nerve block (not in outpatients)
• Prilocaine 1%
10ml Prilocaine 1% for saphenous nerve block

Device:
• ultrasound guidance
In group US the sciatic nerve localization and needle guidance is realized using ultrasound.
• nerve stimulation technique
In the group NS sciatic nerve localization and needle guidance is realized using nerve stimulation technique. However, ultrasound is used observing (Observer) the procedure, but blinded for the physician (Anesthetist) performing the block.

Locations

Country	Name	City	State
n/a

Sponsors (1)

Lead Sponsor	Collaborator
Helios Research Center

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Success Rate Without Supplementation	After injection of local anesthetic a waiting period of 30-60 minutes was defined before completing a failed block.; success without supplementation = no additional analgetics or rescue blocks required (success rate without supplementation, outcome measure 1); 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); failed block = change of anesthetic procedure (general, spinal) or rescue blocks proximal of the sciatic division	within 30-60 minutes after injection of the local anesthetic	No
Primary	Time Until Readiness for Surgery (Minutes)		within 60 minutes after injection of the local anesthetic	No
Primary	Success Rate With Supplementation	After injection of local anesthetic a waiting period of 30-60 minutes was defined before completing a failed block.; success without supplementation = no additional analgetics or rescue blocks required (success rate without supplementation, outcome measure 1); 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); failed block = change of anesthetic procedure (general, spinal) or rescue blocks proximal of the sciatic divisionSucces rate with supplementation	later than 30-60 minutes after injection of the local anesthetic	No