Plasma Ropivacaine Concentrations After Sciatic Nerve Block in Patients With Chronic Kidney Disease

Study Overview
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Brief Summary
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This prospective observational study aimed to examine the pharmacokinetics of ropivacaine in patients with chronic kidney disease after sciatic nerve block. Sciatic nerve block for foot and ankle surgery will be performed using ropivacaine under ultrasound-guidance, and arterial blood test will be taken for total plasma ropivacaine concentration at 2.5, 5, 15, 30, 60 minutes and 2, 6, 24 hours after sciatic nerve block.

Official Title
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Plasma Ropivacaine Concentrations After Peripheral Nerve Block in Patients With Severe Renal Dysfunction

Conditions
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Regional Anesthesia Morbidity, Local Anesthetic Drug Adverse Reaction

Intervention / Treatment
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* Procedure: Sciatic nerve block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients scheduled for foot and ankle surgery Patients with chronic kidney disease (glomerular filtration rate < 60 ml/min/1.73m2) (changed from 30 ml/min/1.73m2 to facilitate patient recruitment) Patients who are thought to be clinically helpful to receive sciatic nerve block rather than general anesthesia because of comorbidities such as cardiopulmonary dysfunction and cerebral dysfunction Exclusion Criteria: Patients who need to renal replacement therapy, such as hemodialysis Patients with liver disease (aspartate transaminase OR alanine transaminase > 80 IU/L) Patients with allergic disease Patients with previous history of drug allery Patients with chronic pain persisting 3 months

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sciatic nerve block<br>Patients scheduled for foot and ankle surgery under sciatic nerve block and who had chronic kidney disease | Procedure: Sciatic nerve block<br>* Sciatic nerve block will be performed using ropivacaine (2.5mg/kg) under ultrasound-guidance with nerve stimulator.<br>* Other names: Popliteal block;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma concentration of unbound ropivacaine | whether the unbound plasma concentration of ropivacaine was maintained under 0.56 mcg/ml that was determined as toxic level in a previous study. | 2.5, 5, 15, 30, 60 minutes and 2, 6, 24 hours after sciatic nerve block | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma concentration of 3-OH-ropivacaine | metabolite of ropivacaine | 2.5, 5, 15, 30, 60 minutes and 2, 6, 24 hours after sciatic nerve block | 
| Plasma concentration of pipecoloxylidide | metabolite of ropivacaine | 2.5, 5, 15, 30, 60 minutes and 2, 6, 24 hours after sciatic nerve block | 
| Postoperative pain score | 11-point numeric rating scale ranging from '0' representing one extreme (e.g. extremely dissatisfied) to '10' representing the other extreme (e.g. extremely satisfied) | 2, 6, 24 hours after sciatic nerve block | 
| Local anesthetic systemic toxicity | numbness of the tongue, twitching, convulsion, dysarrhythmia, coma | 2, 6, 24 hours after sciatic nerve block |