Effect of Intrathecal Fentanyl on Spinal Anesthesia During Dexmedetomidine Infusion

Study Overview
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Brief Summary
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Intravenous infusion of dexmedetomidine during procedure was known to be associated prolonged duration of spinal anesthesia. In patients receiving dexmedetomidine infusion during procedure, it has been not evaluated whether use of adjuvant intrathecal fentanyl had additional prolonging effect on duration of spinal anesthesia or not. Therefore, the investigators planned this trial to compare clinical outcomes in patients receiving spinal anesthesia with heavy bupivacaine only and heavy bupivacaine plus fentanyl adjuvant.

Official Title
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Effect of Intrathecal Fentanyl on Spinal Anesthesia During Dexmedetomidine

Conditions
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Anesthesia, Spinal

Intervention / Treatment
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* Drug: fentanyl
* Drug: bupivacaine only


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients undergoing total knee replacement arthroplasty under spinal anesthesia Exclusion Criteria: Contraindication of spinal anesthesia inability to communicate morbid obesity (BMI > 30kg/m2) spine abnormality severe cardiac dysfunction Height <155cm, or > 180cm contraindication to fentanyl

Ages Eligible for Study
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Minimum Age: 18 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: intrathecal fentanyl<br>heavy bupivacaine 14mg and fentanyl 20mcg will be injected intrathecally during spinal anesthesia | Drug: fentanyl<br>* intrathecal fentanyl will be added as adjuvant for spinal anesthesia using heavy bupivacaine, while dexmedetomidine will be infused intravenously during operation<br>* Other names: Hana Pharmacy;|
| Experimental: bupivacaine only<br>heavy bupivacaine 14mg will be injected intrathecally during spinal anesthesia | Drug: bupivacaine only<br>* heavy bupivacaine will be injected intrathecally during spinal anesthesia, without fentanyl, while dexmedetomidine will be infused intravenously during operation<br>* Other names: AstraZeneca;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Two segment sensory block regression time | Time from highest sensory block level to two segment regression | From completion of spinal anesthesia, to end of surgery, an expected average of 2 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| motor block | modified Bromage scale | From completion of spinal anesthesia, to end of surgery, an expected average of 2 hours | 
| postoperative pain score | VAS scale | at op day, at postoperative 1st day, at postoperative 2nd day | 
| postoperative nausea and vomiting | VAS scale | at op day, at postoperative 1st day, at postoperative 2nd day | 
| intraoperative incidence of hypotension | hypotension : SBP decreased by more than 30% of baseline SBP | From completion of spinal anesthesia, to end of surgery, an expected average of 2 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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fentanyl, dexmedetomidine