Pharmacodynamic Interactions of Propofol and Dexmedetomidine on Intravenous Anesthesia

Study Overview
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Brief Summary
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The purpose of this study is to determine pharmacodynamic interactions of propofol and dexmedetomidine,exploring the effect of dexmedetomidine on propofol unconsciousness median effective concentration (EC50).

Detailed Description
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64 cases were randomly divided into four groups, In each group, dexmedetomidine target plasma concentration are 0, 0.4, 0.6, 0.8 ng/ml. Dexmedetomidine administered 15 min before target controlled infusion of propofol. The propofol infusion was started to provide a target effect-site concentration of 1.0ug/ml, and increased by 0.2ug/ml until loss of consciousness when the effect-site concentration and target concentration equilibrium.

Official Title
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Pharmacodynamic Interactions of Propofol and Dexmedetomidine on Target-controlled Infusion Intravenous Anesthesia During the Induction

Conditions
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Pharmacodynamic Interaction

Intervention / Treatment
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* Drug: 0.0ng/ml Dexmedetomidine
* Drug: 0.4ng/ml Dexmedetomidine
* Drug: 0.6ng/ml Dexmedetomidine
* Drug: 0.8ng/ml Dexmedetomidine
* Drug: Propofol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Weight:18≦ BMI≦25 Written informed consent from the patient or the relatives of the participating patient. Exclusion Criteria: A previous history of intolerance to the study drug or related compounds and additives. Existing significant haematological, endocrine, metabolic or gastrointestinal disease.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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 |
| --- | --- |
| Placebo Comparator: Propofol and 0.0ng/ml Dexmedetomidine<br>Propofol infusion was started to provide an effect-site concentration of 1.0ug/ml after Dexmedetomidine which target plasma concentration is 0.0ng/ml administered for 15min, and increased by 0.2ug/ml until the patient's consciousness disappears. | Drug: 0.0ng/ml Dexmedetomidine<br>* Dexmedetomidine target plasma concentration is 0.0ng/ml<br>Drug: Propofol<br> <br> |
| Experimental: Propofol and 0.4ng/ml Dexmedetomidine<br>Propofol infusion was started to provide an effect-site concentration of 1.0ug/ml after Dexmedetomidine which target plasma concentration is 0.4ng/ml administered for 15min, and increased by 0.2ug/ml until the patient's consciousness disappears. | Drug: 0.4ng/ml Dexmedetomidine<br>* Dexmedetomidine target plasma concentration is 0.4ng/ml<br>Drug: Propofol<br> <br> |
| Experimental: Propofol and 0.6ng/ml Dexmedetomidine<br>Propofol infusion was started to provide an effect-site concentration of 1.0ug/ml after Dexmedetomidine which target plasma concentration is 0.6ng/ml administered for 15min, and increased by 0.2ug/ml until the patient's consciousness disappears. | Drug: 0.6ng/ml Dexmedetomidine<br>* Dexmedetomidine target plasma concentration is 0.6ng/ml<br>Drug: Propofol<br> <br> |
| Experimental: Propofol and 0.8ng/ml Dexmedetomidine<br>Propofol infusion was started to provide an effect-site concentration of 1.0ug/ml after Dexmedetomidine which target plasma concentration is 0.8ng/ml administered for 15min, and increased by 0.2ug/ml until the patient's consciousness disappears. | Drug: 0.8ng/ml Dexmedetomidine<br>* Dexmedetomidine target plasma concentration is 0.8ng/ml<br>Drug: Propofol<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The EC50 of propofol for loss of consciousness | The aim of the investigators study is to define the optimum target concentration (EC50) of propofol for loss of consciousness with different dexmedetomidine target plasm concentration. | within 30 min during the induction of anesthesia | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The EC95 of propofol for loss of consciousness | The aim of the investigators study is to define the optimum target concentration (EC95) of propofol for loss of consciousness with different dexmedetomidine target plasm concentration. | within 30 min during the induction of anesthesia | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pharmacodynamic, Dexmedetomidine, Propofol, Target-controlled Infusion Intravenous Anesthesia