Dose-finding Study: Popliteal Sciatic Nerve Block in Patients Undergoing Diabetic Foot Surgery

Median Effective Concentration of Ropivacaine for Ultrasound-guided Popliteal Sciatic Nerve Block in Patients Undergoing Diabetic Foot Surgery

The purpose of this study was to determine the minimum effective dose of a local anesthetic for proper anesthesia for popliteal sciatic nerve block under ultrasound guidance in patients undergoing surgery for diabetic foot disease.

Study Overview

• Status: Active, not recruiting
• Conditions: Diabetic Foot; Diabetic Neuropathies
• Intervention / Treatment: Other: Maintain the concentration of ropivacaine as same as those used in the previous participant; Other: Decrease the ropivacaine concentration by 0.05% from the concentration used in the previous participant; Other: Increase the ropivacaine concentration by 0.05% from the concentration used in the previous participant

Detailed Description

Unlike general patients, patients with diabetic foot disease often have diabetic neuropathy and thus have increased sensitivity to local anesthetics. Therefore, when performing sciatic nerve block, it is essential to properly adjust the dose to prevent neurotoxicity and delay in recovery due to local anesthetics.

If the appropriate effective dose of local anesthetic for sciatic nerve block is found in patients with diabetic foot through this study, it is expected that it will be a useful basis for establishing a safe anesthetic method in the case of diabetic foot surgery.

• Study Type: Interventional
• Enrollment (Estimated): 45
• Phase: Not Applicable

Contacts and Locations

Study Locations

• South Korea
  • Seoul, South Korea, 03080
    • Seoul National University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 19 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patients who can be operated under popliteal sciatic nerve block among patients undergoing surgery for diabetic foot disease

Exclusion Criteria:

1. Infection of the popliteal region
2. Severe coagulation abnormality
3. Allergic reaction or hypersensitivity to local anesthetics
4. Neurological abnormalities other than diabetic neuropathy in the lower extremity of the operation site
5. When it is impossible to evaluate sensory blockage and motor blockage
6. When the patient refuses

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Sequential Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Sciatic nerve block using same or decreased concentration of local anesthetic; If the sciatic nerve block in the previous participant was successful, the concentration of local anesthetic would be maintained or decreased 0.05% in the next patient based on a random assignment.	Other: Maintain the concentration of ropivacaine as same as those used in the previous participant; Maintain the same concentration of ropivacaine used in the previous participant with an 89% chance through a random assignment; Other: Decrease the ropivacaine concentration by 0.05% from the concentration used in the previous participant; Decrease ropivacaine concentration by 0.05% from the concentration used in the previous participant with an 11% chance through a random assignment
Other: Sciatic nerve block using increased concentration of local anesthetic; If the sciatic nerve block in the previous participant was not successful, the concentration of local anesthetic would be increased 0.05% in the next patient.	Other: Increase the ropivacaine concentration by 0.05% from the concentration used in the previous participant; Increase ropivacaine concentration by 0.05% from the concentration used in the previous participant.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Median effective anesthetic concentration 90 (MEAC 90)	Concentration of ropivacaine required for successful sciatic nerve block in 90% of all patients	within 30 minutes from the popliteal sciatic block

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Median effective anesthetic concentration 50 (MEAC 50)	Concentration of ropivacaine required for successful sciatic nerve block in 50% of all patients	within 30 minutes from the popliteal sciatic block
Sensory block onset time	Check for sensory blockade every 5 minutes until 30 minutes after block performed. For sensory block, cold sense using alcohol swabs is evaluated on the foot, comparing with the opposite foot, on a 3-point scale (0 points if there is no cold sense at all, 1 point if there is a decrease, 2 points if it is the same with the opposite foot). The time it takes to block to 0 point is the sensory blockade onset time.	within 30 minutes from the popliteal sciatic block
Motor block onset time	Check for motor blockade every 5 minutes until 30 minutes after block performed. Dorsiflexion and plantar flexion is evaluated, compared to the opposite foot, on a 3-point scale (0 points for inability to move 1 point for reduced movement 2 points for normal movement). The time it takes to block to 0 point is the motor blockade onset time.	within 30 minutes from the popliteal sciatic block
Block duration	Block duration is the time from when block is performed until the patient first complained of pain at the surgical site post-operatively.	within 24 hours post-operatively
Time to first rescue analgesia	Time to first rescue analgesia is the time from when block is performed until the patient first requested of rescue analgesics post-operatively.	within 24 hours post-operatively
Any adverse events	Unintentional nerve damage that occurs during nerve block, pain, bleeding, infection, hypoxia, hypotension	within 24 hours post-operatively

Collaborators and Investigators

• Sponsor: Seoul National University Hospital
• Investigators: Principal Investigator: Seokha Yoo, MD, Seoul National University Hospital

Study record dates

Study Major Dates

• Study Start (Actual): August 24, 2021
• Primary Completion (Estimated): December 28, 2027
• Study Completion (Estimated): February 29, 2028

Study Registration Dates

• First Submitted: June 28, 2021
• First Submitted That Met QC Criteria: July 21, 2021
• First Posted (Actual): July 28, 2021

Study Record Updates

• Last Update Posted (Actual): April 30, 2026
• Last Update Submitted That Met QC Criteria: April 26, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Endocrine System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Neuromuscular Diseases; Peripheral Nervous System Diseases; Diabetes Mellitus; Diabetic Angiopathies; Diabetes Complications; Skin Diseases; Skin Ulcer; Leg Ulcer; Foot Ulcer; Skin and Connective Tissue Diseases; Diabetic Neuropathies; Diabetic Foot; Amino Acids, Peptides, and Proteins; Sulfur Compounds; Organic Chemicals; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Nucleic Acids, Nucleotides, and Nucleosides; Purines; Amino Acids; Nucleosides; Ribonucleosides; Amino Acids, Sulfur; Adenosine; Purine Nucleosides; Methionine; S-Adenosylmethionine
• Other Study ID Numbers: 2102-120-1220

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No