Perineural Dexmedetomidine and Femoral Nerve Block

Study Overview
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Brief Summary
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The duration of sensory block after single dose of long acting local anesthetics is not sufficient to avoid the postoperative use of opioids. Alpha-2 adrenoceptor agonists such as clonidine have been shown to increase the duration of peripheral nerve block. Dexmedetomidine is a more potent and selective α-2-adrenoceptor compared to clonidine. To the best of our knowledge, the use of Dexmedetomidine as adjuvant to local anesthetic was not previously reported for femoral nerve block.

Official Title
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Perineural Dexmedetomidine as an Adjuvant to Bupivacaine-induced Ultrasound-guided Femoral Nerve Block.

Conditions
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Onset and Duration of Sensory and Motor Block of Femoral Nerve,, Visual Analogue Pain Scores,, Time to First Request of Rescue Analgesics,, Total Morphine Consumption in 24 Hours

Intervention / Treatment
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* Drug: peri-neural dexmedetomidine as adjuvant to bupivacaine in femoral nerve block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: all patients with ASA physical status I or II, scheduled for diagnostic knee arthroscopy Exclusion Criteria: Patients who are refusing regional block, patients with diabetic peripheral neuropathy, renal or hepatic dysfunction, inflammation or infection at the puncture site, and history of allergic reaction to study medications

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: group B: control bupivacaine group<br>Patient in this group will receive 25 ml bupivacaine 0.5% plus 0.5 ml normal saline peri-neurally and 0.5 ml subcutaneous normal saline. | Drug: peri-neural dexmedetomidine as adjuvant to bupivacaine in femoral nerve block<br>* ultrasound quided femoral nerve block with injection of 15 ml bupivacaine 0.5% perineurally with 0.5 ml dexmedetomidine (50 microgram) either perineurally or subcutaneously. After adequate assessment of femoral nerve block, patients will be transferred to the operating room to receive a standard general anesthesia<br>|
| Experimental: Group B-peri-DEX: Peri-neural Dexmedetomidine<br>Patients in this group will receive 25 ml of 0.5% bupivacaine plus 0.5 ml (50 microgram) Dexmedetomidine peri-neurally and 0.5 ml subcutaneous normal saline | Drug: peri-neural dexmedetomidine as adjuvant to bupivacaine in femoral nerve block<br>* ultrasound quided femoral nerve block with injection of 15 ml bupivacaine 0.5% perineurally with 0.5 ml dexmedetomidine (50 microgram) either perineurally or subcutaneously. After adequate assessment of femoral nerve block, patients will be transferred to the operating room to receive a standard general anesthesia<br>|
| Active Comparator: Group B-sys-DEX:Systemic Dexmedetomidine<br>Patients in this group will receive 25 ml bupivacaine plus 0.5 ml saline peri-neurally and 0.5 ml (50 microgram) subcutaneous Dexmedetomidine. | Drug: peri-neural dexmedetomidine as adjuvant to bupivacaine in femoral nerve block<br>* ultrasound quided femoral nerve block with injection of 15 ml bupivacaine 0.5% perineurally with 0.5 ml dexmedetomidine (50 microgram) either perineurally or subcutaneously. After adequate assessment of femoral nerve block, patients will be transferred to the operating room to receive a standard general anesthesia<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The primary outcome measure of this study will be the change of sensory block over time. | Over a period of 30 min after injection of the study medications, a blinded investigator will assess sensory block with pinprick test using a 3-point scale: 0 ═ complete loss of sensation, 1 ═ partial loss of sensation and 2 ═ normal sensation (10). Pinprick test will be done in comparison to the contralateral area at the sensory distribution of the femoral nerve | intraoperatively every 5 minutes for the first 30 minutes of the operation, then postoperatively every 2 hours for 24hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| onset of motor and sensory block | The onset time of sensory and motor block will be: the time elapsed between the end of injection and the development of complete block (score of 0 at all dermatomes or no movement of the quadriceps muscle. | up to 30 minutes after the end of injection | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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femoral nerve block, peri-neural dexmedetomidine