Intravenous Versus Perineural Dexmedetomidine as Adjuvant in Adductor Canal Block for Total Knee Arthroplasty

Study Overview
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Brief Summary
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Shivering increases the cardiac and systemic energy expenditure, oxygen consumption and carbon dioxide production. Definitive prevention and treatment of shivering is necessary to decrease the related complications and increase post-anesthetic comfort.

Detailed Description
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Dexmedetomidine a highly selective α2 adrenergic agonist used effectively as a safe analgesic via different routes and mechanisms, including intravenous (i.v.), neuraxial and perineural routes. Dexmedetomidine has been used for prevent shivering but, the results of its efficacy is still controversy. No studies to date have investigated the best administration route of dexmedetomidine to dominantly prevent the occurrence of shivering after spinal anesthesia or associated with the least grade. This prospective, randomized, double blinded study was designed to investigate the best administrative route of dexmedetomidine firstly, as a preventive of neuraxial shivering and secondly as adjunctive analgesic. The incidence of post-spinal anesthesia shivering was the primary outcome. Perioperative hemodynamics, postoperative pain scores during rest and at 45-degree flexion of the knee, the analgesic duration, the first postoperative day analgesic consumption, the sedation score and early ambulation ability were the secondary outcomes.

Official Title
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Intravenous Versus Perineural Dexmedetomidine as Adjuvant in Adductor Canal Block for Total Knee Arthroplasty

Conditions
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Post Spinal Anesthesia Shivering

Intervention / Treatment
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* Drug: intravenous dexmedetomidine
* Drug: adductor canal block dexmedetomidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adult patients both genders American Society of Anesthesiologists physical status I and II scheduled for unilateral primary TKA under spinal anesthesia Exclusion Criteria: chronic opioid use known allergy to the used drugs any contraindications to regional anesthesia like; patient refusal, coagulopathy, neuropathy or infection at the injection site

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 75 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: intravenous dexmedetomidine<br>20 mL 0.25% levobupivacaine plus 1 mL normal saline will be administrated for adductor-canal-blockade while for intravenous solution; 0.5µg.kg-1 dexmedetomidine diluted in 20 mL normal saline will be prepared | Drug: intravenous dexmedetomidine<br>* adductor-canal-blockade with 20 mL 0.25% levobupivacaine plus 1 mL normal saline while, the intravenous solution; consists of 0.5µg.kg-1 dexmedetomidine diluted in 20 mL normal saline<br>|
| Active Comparator: adductor-canal-blockade dexmedetomidine<br>20 mL 0.25% levobupivacaine containing 1 mL of 0.5 mcg.kg-1 dexmedetomidine will be used for adductor-canal-blockade whereas, 20 mL 0.9% saline will be prepared for intravenous infusion | Drug: adductor canal block dexmedetomidine<br>* adductor-canal-blockade with 20 mL 0.25% levobupivacaine plus 1 mL of 0.5µg.kg-1 dexmedetomidineline while, the intravenous solution;consists of 20 mL normal saline<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| incidence of post-spinal anesthesia shivering | 5-point scale (0= no shivering, 1 =piloerection or peripheral vasoconstriction but no visible shivering; 2 =muscular activity in only one muscle group; 3 =muscular activity in more than one muscle group but not generalized and 4 = shivering involving the whole body) | up to 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The analgesic duration | the time from adductor-canal-blockade injection till the first of postoperative dose of rescue analgesic | during the first postoperative 24 hours | 
| total cumulative doses of rescue analgesic | given when visual analog scale for pain ≥ 40 | after the first postoperative 24 hours | 
| Modified Ramsay sedation scale | Awake and alert, minimal or no cognitive impairment Awake but tranquil, purposeful responses to verbal commands at a conversational level Appears asleep, purposeful response to verbal commands at a conversational level Appears asleep, purposeful responses to commands but at a louder than conversational level, requiring light glabellar tap, or both Asleep, sluggish purposeful responses only to loud verbal commands, strong glabellar tap, or both Asleep, sluggish purposeful responses only to painful stimuli Asleep, reflex withdrawal to painful stimuli only Unresponsive to external stimuli, including pain | after 0.5 hour from adductor-canal-blockade then, 2, 4, 6, 8, 10, 12 and 24 hours postoperatively | 
| non-invasive arterial blood pressure | mmHg | every 15 minutes after spinal anesthesia till the end of the surgery then at 0.5, 1, 3, 6, 12 hours postoperative | 
| Heart rate | beat per minute | every 15 minutes after spinal anesthesia till the end of the surgery then at 0.5, 1, 3, 6, 12 hours postoperative | 
| postoperative pain | visual analog scale for pain (0 mm= no pain, and 100 = the worst possible pain) | preoperative, 2, 4, 6, 8, 10, 12 and 24 hours postoperatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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dexmedetomidine-adductor canal block