The Effects of Various Concentrations of Ropivacaine on the Onset and Duration of Ankle Blocks

Not Applicable

Not yet recruiting

• Conditions: Hallux Valgus; Anesthesia
• Interventions: Drug: 0.25% ropivacaine; Drug: 0.5% ropivacaine; Drug: 1% ropivacaine

• Registration Number: NCT06185608
• Lead Sponsor: Ziekenhuis Oost-Limburg

Brief Summary

Peripheral nerve blocks are essential in ensuring effective regional anesthesia and postoperative analgesia in forefoot surgery for hallux valgus repair. Many factors influence the onset and duration of peripheral nerve blocks. In the advent of ultrasound-guided nerve blocks, the accuracy in administering LA has significantly improved, potentially reducing the required dosage, which is also associated with less risk for toxicity. However, the effect of the concentration of LA on the onset time and duration of ultrasound-guided ankle blocks for forefoot surgery has not yet been studied. This poses a clinically relevant dilemma regarding the necessity of administering lower or higher concentrations of ropivacaine to achieve a clinically relevant faster onset time and longer duration of an ankle block.

Detailed Description

This study aims to evaluate the differential effects of 0.25%, 0.5%, and 1% ropivacaine on the onset time and duration of ultrasound-guided ankle blocks in patients having forefoot surgery for anesthesia and postoperative analgesia. We hypothesize that the use of 1% ropivacaine for ultrasound guided ankle blocks will result in a significantly faster onset time and a longer sensory block duration, and thus analgesia, compared to the use of 0.25% and 0.5% ropivacaine in patients having forefoot surgery. The primary outcome is the difference in the duration of the sensory blocks. The secondary outcomes are the difference in onset time of the sensory block, motor function, the postoperative pain scores, opioid consumption, and proportion of failed blocks.

Study Timeline

• Study First Submitted: 2023-12-15
• Study First Submitted QC: 2023-12-15
• Study First Posted: 2023-12-29
• Status Verified: 2025-04
• Last Update Submitted: 2025-04-11
• Last Update Posted: 2025-04-16
• Study Start: 2025-04-22
• Primary Completion: 2027-03-01
• Study Completion: 2027-08-01

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 174

Inclusion Criteria

• Provide signed and dated informed consent
• Age 18 to 75 years, scheduled for elective forefoot surgery for hallux valgus repair under unilateral ankle block at ZOL Genk
• ASA physical I-II-III
• Able to ambulate (ability to walk independently, with or without assistive devices)
• Able to learn and perform study sensory and motor assessment by exhibiting sensitivity to pinprick, cold, and light touch (tested beforehand with pinprick/cold/ light touch sensation test) as the patient will have to perform these sensory and motor assessments by him/herself at home at postoperative day 0 to 2

Exclusion Criteria

• Language barrier
• Preexisting lower extremity neuropathy
• Contraindications to ankle block (local infection, edema, burn, soft tissue trauma, or distorted anatomy with scarring in the area of block placement)
• Contraindications for use of NSAIDs
• Allergy to local anesthetics
• Uncontrolled anxiety, psychiatric or neurological disorder that might interfere with study assessment
• Weight below 50 kg based on a maximum dose of 3 mg/kg ropivacaine and a maximum dose of 150 mg ropivacaine.
• Preoperative use of opioids or gabapentin less than 3 days before surgery
• Contraindications for use of paracetamol
• Contraindications for use of tramadol

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
0.25% ropivacaine group	0.25% ropivacaine	This group will receive a total of 15 mL of 0.25% ropivacaine.
0.5% ropivacaine group	0.5% ropivacaine	This group will receive a total of 15 mL of 0.5% ropivacaine.
1% ropivacaine group	1% ropivacaine	This group will receive a total of 15 mL of 1% ropivacaine.

Primary Outcome Measures

Name	Time	Method
Duration	48 hours	The difference in sensory block duration across the different groups.

Secondary Outcome Measures

Name	Time	Method
Onset	30 minutes	The difference in sensory block onset across the different groups.
Motor function	48 hours	The difference in motor function across the different groups. The motor function will be evaluated with NRS during movement and at rest. The following scale will be used: 0 full strength, 1 ability to move but weakness experienced, 2 unable to move and no strength.
Pain scores	48 hours	The difference in postoperative pain scores across the different groups using a numeric rating scale from 0 being 'no pain' to 10 being 'worst pain imaginable'. The highest score (10) correlates with severe pain and thus worse outcome.
Opioid consumption	48 hours	The difference in opioid consumption across the different groups.
Proportion failed blocks	48 hours	The difference in the proportion of failed blocks across the different groups.