Mepivacaine Versus Bupivacaine Onset Time in Ultrasound-guided Ankle Blocks

Study Overview
=================
Brief Summary
-----------------
The purpose of this research is to determine if both local anesthetics (mepivacaine and bupivacaine) are similar in their onset of sensory block to assess the efficiency of ultrasound-guided ankle blocks in our practice. Currently it is the standard of care to perform ankles blocks with both mepivacaine and bupivacaine. However, given similarity in their safety profile researchers would like to compare if one is non-inferior to the other in terms of onset time of ankle block.

Official Title
-----------------
Onset of Sensory Blockade in Ultrasound-Guided Ankle Block With Mepivacaine Versus Bupivacaine: A Randomized Non-Inferiority Clinical Trial

Conditions
-----------------
Ankle Block, Foot Surgery

Intervention / Treatment
-----------------
* Drug: Mepivacaine
* Drug: Bupivacaine


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age greater than or equal to 18 years old. Patients who provide informed consent to participate. Patients undergoing foot surgery who require a peripheral nerve block of the ankle as primary anesthesia. ASA (American Society of Anesthesiology) Physical Status Classification I - III. Exclusion Criteria: Inability to consent. Allergy to local anesthetic. Infection at site of injection. Pregnancy. Coagulopathy. Hepatic or renal failure. Preexisting neuropathy in operative limb. Planned spinal anesthetic or general anesthesia.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Mepivacaine group<br>Subjects will receive an ultrasound-guided peripheral nerve block at the ankle with mepivacaine prior to undergoing foot surgery | Drug: Mepivacaine<br>* Up to two 30 ml vials of mepivacaine 1.5% via ultrasound-guided nerve blockade of the tibial and deep peroneal nerves<br>|
| Active Comparator: Bupivacaine group<br>Subjects will receive an ultrasound-guided peripheral nerve block at the ankle with bupivacaine prior to undergoing foot surgery | Drug: Bupivacaine<br>* Up to two 30 ml vials of bupivacaine 0.5% via ultrasound-guided nerve blockade of the tibial and deep peroneal nerves<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Onset of sensory Blockage | Time in minutes for successful surgical sensory blockade following the ankle block | 20 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Block Failure | Number of subjects to experience block failure as defined as opioid administration operatively and /or conversion to general anesthesia | 20 minutes | 
| Pain Scores | Pain scores in post-anesthesia care unit (PACU) will be obtained using the numerical rating scale (0-10 point scale with 0 representing no pain and 10 representing the worst possible pain) | Post-procedural, approximately 2-4 hours | 
| Total opioid received intra-operatively | Total amount of opioid received intra-operatively | Intra-operatively, approximately 4-6 hours | 
| Time to first opioid use | Time measured in minutes to the first opioid use | 24 hours | 
| Number of complications | Total number of procedural complications | 24 hour | 
| Total anesthesia-related time | Measured in minutes, defined as performance time plus onset time of local anesthesia | 20 minutes | 
| Overall Benefit of Analgesia Score (OBAS) | Seven questions to access pain intensity, adverse effects and satisfaction with treatment. Possible score range from 0 to 24, with higher scores indicating worse outcome | 24 hours after discharge | 
| Total opioid use after discharge | Total amount of opioids used used for pain control after discharge | 24 hours after discharge | 
| Duration of the ankle block | Length of time measured in minutes the patient to felt until the ankle block completely wore off | 24 hours after discharge | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Ultrasound-Guided Ankle Block, Regional anesthesia, Local anesthesia