The Effects of Different Doses of Dexmedetomidine on Propofol Requirement for Loss of Consciousness Undergoing Bispectral Index: a Double-blinded, Placebo-controlled Trial

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the effects of different dexmedetomidine on the propofol requirement for loss of consciousness undergoing bispectral index.

Detailed Description
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It has been shown that dexmedetomidine was an efficacious and safe adjuvant in general anaesthesia. Administration of dexmedetomidine during the preoperative period has been demonstrated to reduce the requirement of opioid analgesics and other sedative and hypnotic drugs.Therefore, the study is designed to measure the effect of intravenous dexmedetomidine premedication on the propofol dose requirement and bispectral index at loss of consciousness.

Official Title
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The Effects of Different Dexmedetomidine on the Propofol Requirement for Loss of Consciousness Undergoing Bispectral Index

Conditions
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Loss of Consciousness

Intervention / Treatment
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* Other: normal saline
* Drug: dexmedetomidine 0.5 µg/kg
* Drug: dexmedetomidine 1.0 µg/kg


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA physical status I-II Aged 18-65 years Body Mass Index 18.0～24.5 kg/m2 Without hearing impairment Exclusion Criteria: Bradycardia Atrioventricular block Neurologic disorder and recent use of psychoactive medication Allergic to the drugs

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Group control<br>24 eligible patients are received equal volumes of saline intravenously for 10 minutes | Other: normal saline<br>* receive equal volume of normal saline<br>|
| Active Comparator: Group dexmedetomidine 0.5 µg/kg<br>24 eligible patients are received dexmedetomidine 0.5 µg/kg intravenously for 10 minutes | Drug: dexmedetomidine 0.5 µg/kg<br>* receive dexmedetomidine 0.5 µg/kg<br>|
| Active Comparator: Group dexmedetomidine 1.0 µg/kg<br>25 eligible patients are received dexmedetomidine 1.0 µg/kg intravenously for 10 minutes | Drug: dexmedetomidine 1.0 µg/kg<br>* receive dexmedetomidine 1.0 µg/kg<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The propofol requirement for pretreatment of dexmedetomidine by micro-pump until loss of consciousness |  | To infuse dexmedetomidine and saline completely ten minutes after | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The bispectral index values when patients loss of consciousness |  | To infuse dexmedetomidine and saline completely ten minutes after | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Propofol, Dexmedetomidine, Dose, Bispectral index monitor