Does Interneural Local Anesthetic Spread at the Site of Sciatic Nerve Bifurcation Shorten Block Onset Time?

Regional Anesthesia Clinical Trial

Official title:

Does Interneural Local Anesthetic Spread at the Site of Sciatic Nerve Bifurcation Shorten Block Onset Time?

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01568476
• Other study ID #: 11-0059-A
• Status: Completed
• Phase: N/A
• First received: March 6, 2012
• Last updated: December 1, 2017
• Start date: July 2011
• Est. completion date: June 2013

Study information

• Verified date: December 2017
• Source: University Health Network, Toronto
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Following foot and ankle surgery, ultrasound-guided sciatic nerve block (SNB) at the popliteal fossa decreases post-operative pain and opioid consumption. At the popliteal fossa, the sciatic nerve bifurcates to form the Common Peroneal Nerve (CPN) and Tibial Nerve (TN). Studies have shown that when both branches are blocked separately distal to the bifurcation site, block onset time is reduced by 30%. Through clinical observation, the investigators found that onset time is further shortened when ultrasound-guided SNB is performed at the site of bifurcation. This is because the local anesthetic spreads interneurally. The purpose of this study is to compare the block onset time of an ultrasound-guided sciatic nerve block at the site of nerve bifurcation with the blockade of each terminal nerve separately (TN and CPN) distal to sciatic nerve bifurcation.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 88
• Est. completion date: June 2013
• Est. primary completion date: June 2013
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 85 Years

Eligibility

Inclusion Criteria:

• ASA physical status I-III

• 18-85 years of age, inclusive

• 50-120 kg, inclusive

• 150 cm of height or greater

Exclusion Criteria:

• Contraindications to sciatic nerve block (e.g., allergy to local anesthetics, coagulopathy, malignancy or infection in the popliteal area)

• Significant peripheral neuropathy or neurological disorder affecting the lower extremity

• Pregnancy

• History of alcohol or drug dependency/abuse

• History of significant psychiatric conditions that may affect patient assessment

Related Conditions & MeSH terms

• Post Operative Analgesia
• Regional Anesthesia
• Sciatic Nerve Block

Intervention

Procedure:
• Distal
Blockade of both terminal branches of Sciatic nerve separately, distal to bifurcation
• Interneural
Sciatic nerve blockade at the site of bifurcation

Locations

Country	Name	City	State
Canada	Toronto Western Hospital	Toronto	Ontario

Sponsors (1)

Lead Sponsor	Collaborator
University Health Network, Toronto

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Block onset Time	We aim to compare the block onset time of an ultrasound-guided sciatic nerve block at the site of nerve bifurcation resulting in interneural spread of local anesthetic with that of blockade of each terminal nerve separately (TN and CPN), distal to sciatic nerve bifurcation. We hypothesize that sciatic nerve blockade at the site of bifurcation with interneural local anesthetic spread within a common epineural sheath results in shorter onset time compared to blockade of each terminal nerve distal to sciatic nerve bifurcation.	every 5 minutes up to 45 minutes of the block or until surgery starts
Secondary	Extent of longitudinal local anesthetic solution spread		starting at block administration till 5 minutes after complete injection
Secondary	Nerve diameter prior to and following injection		starting at block administration till 5 minutes after complete injection
Secondary	Block procedure time		starting at block administration till complete injection(up to 10 minutes)
Secondary	Number of skin punctures required.		starting at first attempt of block administration till complete injection(up to 10 minutes)
Secondary	Block success rate		starting after complete injection up to 45 minutes
Secondary	Incidence of block-related complications	Incidence of block-related complications (vascular puncture, hematoma formation, intravascular injection and post-operative neurologic deficit) will be documented, but due to the very low incidence in all block-related complications, this study is not powered to show a difference in safety	immediately , at 24 hours and Post operative day 7
Secondary	Postoperative pain	Postoperative pain: Postoperative pain using a verbal rating score (0-10, where 0= no pain, 10=excruciating pain) at 0, 30, 60, 90 and 120 min upon admission to post-anesthetic care unit.	starting at patient's arrival at post-anesthetic care unit till 120 minutes