Circumferential Spread of Anesthetic and Success in Sciatic Nerve Blockade

Does Ensuring Circumferential Local Anesthetic Spread Improve the Success of Ultrasound Guided Sciatic Nerve Block at the Popliteal Fossa?

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00802581

Enrollment

Registered

2008-12-05

Start date

2009-05-31

Completion date

2010-12-31

Last updated

2011-12-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Sciatic Nerve Blockade for Foot/Ankle Surgery

Keywords

sciatic nerve block, local anesthetic, lidocaine, ankle surgery, foot surgery, ultrasound-guided regional anesthesia, circumferential spread, anesthetic infiltration

Brief summary

Current practices when performing any peripheral nerve block may or may not involve ensuring circumferential spread of local anesthetic around the nerve. Ensuring circumferential spread can involve several redirections of the needle above and below the nerve, and potentially could result in either more discomfort for the patient or an increased chance of inadvertent direct trauma to the nerve. Not ensuring spread around the nerve may result in a slower and less complete blockade. The investigators suspect that by ensuring complete spread around the nerve, the speed of block onset would be quicker because it avoids the loss due to diffusion time.

Interventions

PROCEDURECircumferential spread of local anesthetic

The anesthetist will ensure, under ultrasound guidance, that local anesthetic (1 mL of 1% lidocaine) surrounds the sciatic nerve.

PROCEDURENon-circumferential spread of local anesthetic

The anesthetist will perform a single shot injection of local anesthetic (1 mL of 1% lidocaine) near the sciatic nerve under ultrasound guidance, without ensuring circumferential spread around the nerve.

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

DOUBLE (Subject, Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

18 Years to 85 Years

Healthy volunteers

Inclusion criteria

1. English-speaking 2. ASA physical status I-III 3. 18-85 years of age, inclusive 4. 50-110 kg, inclusive 5. 150 cm of height or grater 6. Scheduled for elective foot or ankle surgery

Exclusion criteria

1. Contraindications to sciatic nerve block (e.g., allergy to local anesthetics, coagulopathy, malignancy or infection in the popliteal area) 2. Significant peripheral neuropathy or neurologic disorder affecting the lower extremity 3. Pregnancy 4. Contraindications to, allergies to, and/or past adverse reactions to study medications (local anesthetics, opioid analgesics) 5. History of alcohol or drug dependency/abuse 6. History of long term opioid intake 7. History of significant psychiatric conditions that may affect patient assessment

Design outcomes

Primary

Measure	Time frame
Onset time of sciatic nerve blockade.	Every 5 minutes for 30 minutes after anesthetic injection

Secondary

Measure	Time frame
Block success, time required to perform block, complications/adverse events, number of needle passes, patient discomfort	24 hours

Countries

Canada

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026