Ultrasound-Guided Continuous Sciatic Nerve Blocks: Popliteal Versus Subgluteal Catheters

Study Overview
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Brief Summary
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To determine the relationship between perineural catheter location along the sciatic nerve (popliteal versus subgluteal placement) and infusion effects for ultrasound-guided continuous sciatic nerve blocks.

Official Title
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Ultrasound-Guided Continuous Sciatic Nerve Blocks: Popliteal Versus Subgluteal Catheters

Conditions
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Foot Surgery

Intervention / Treatment
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* Procedure: Subgluteal Sciatic Nerve Block
* Procedure: Popliteal Sciatic Nerve Block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: undergoing foot surgery with a sciatic perineural catheter for postoperative analgesia spending the first postoperative night hospitalized age 18 years or older Exclusion Criteria: pregnancy inability to communicate with the investigators and hospital staff incarceration clinical neuropathy in the surgical extremity

Ages Eligible for Study
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Minimum Age: 18 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Subgluteal Sciatic Nerve Block<br>Patients randomized to this group will receive a sciatic nerve block with the catheter tip insertion at the subgluteal location 1-3 cm caudad to the inferior border of the gluteus maximus muscle. | Procedure: Subgluteal Sciatic Nerve Block<br>* Patients randomized to this group will receive a sciatic nerve block with the catheter tip insertion at the subgluteal location 1-3 cm caudad to the inferior border of the gluteus maximus muscle. After catheter placement, outcome measures will be assessed.<br>|
| Active Comparator: Popliteal Sciatic Nerve Block<br>Patients randomized to this group will receive a sciatic nerve block with the catheter tip insertion at the popliteal location 1-3 cm cephalad to the sciatic bifurcation. | Procedure: Popliteal Sciatic Nerve Block<br>* Patients randomized to this group will receive a sciatic nerve block with the catheter tip insertion at the popliteal location 1-3 cm cephalad to the sciatic bifurcation. After Catheter placement outcome measures will be assessed.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Muscle Strength (MVIC) of the hamstring muscles | We will evaluate hamstring strength which is innervated by the sciatic nerve with an isometric force electromechanical dynamometer to measure the force produced during a maximum voluntary isometric contraction (MVIC) in a seated position with the knees flexed at 90º | 08:00-09:00 morning after surgery as a percentage of baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensory Effect | We will evaluate tolerance of transcutaneous electrical stimulation. Electrocardiogram pads will be placed on the plantar and dorsal aspects of the foot, and attached to a nerve stimulator. The current will be increased from 0 mA until subjects described a buzzing sensation (not painful), at which time the current will be recorded as the tolerated level and the nerve stimulator turned off. | 08:00-09:00 morning after surgery | 
| Pain Scores | Surgical pain scores both average and worse as collected by nursing staff; and also the average and worse pain during the primary endpoint measurement | from leaving the PACU until 08:00 the morning after surgery | 
| Sleep Disturbances | Total number of times patient woke in the night due to surgical pain. | recorded at 08:00-09:00 the morning after surgery for the previous night | 
| Total Infusion | Total infusiond duration in time and volume and total number of boluses delivered via catheter. | recorded at 08:00-09:00 the morning following Surgery | 
| Anesthetic Leakage | Leakage from the catheter site noted by patient. | recorded at 08:00-09:00 the morning following Surgery | 
| analgesic consumption | Hourly analgesic consumption. | end of PACU stay until 08:00-09:00 the morning following surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pain, Surgery, Catheter, Nerve Block, Popliteal, Subgluteal, Sciatic, UCSD, Moderate-to-severe pain, Perineural Catheter, Orthopedic Surgery, foot surgery surgery, sciatic perineural catheter, age =>18