Effects and Mechanism of Pretreatment With Dexmedetomidine to Etomidate Induce Myoclonus

Study Overview
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Brief Summary
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By observing the difference of plasma homovanillic acid concentrations and brain electrical consciousness monitoring Narcotrend index, study the possible mechanism of influencing Etomidate induced myoclonus with Dexmedetomidine pretreatment during general anesthesia induction period.

Official Title
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Effects and Mechanism of Pretreatment With Dexmedetomidine to Etomidate Induce Myoclonus During General Anesthesia Induction Period

Conditions
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Myoclonus

Intervention / Treatment
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* Drug: Low-dose Dexmedetomidine
* Drug: High-dose dexmedetomidine
* Drug: normal saline
* Drug: Etomidate
* Drug: midazolam，fentanyl，rocuronium
* Drug: propofol，remifentanil，cis atracurium


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Sign the informed consent American Society of Anesthesiologists (ASA)classification:class I II;undergoing elective surgery patients Aged between 18 and 55, 49-67 kg weight Body Mass Index（BMI）： 20-30 kg/m2 Did not use any analgesic or sedatives drugs within 24 h pre-operation Exclusion Criteria: Recently patients undergoing sedative drugs and antidepressant treatment Serious vision, hearing impairment or other reasons can not communicate Serious neurological disease, pregnancy, diseases of the cardiovascular system； BMI is Less than the standard 80% or higher than the standard 120%

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low-dose Dexmedetomidine<br>-Pretreatment before anesthesia induction：Intravenous injection dexmedetomidine 0.5 µg/kg，completed within 15 minutes. | Drug: Low-dose Dexmedetomidine<br>* Pretreatment：Intravenous injection dexmedetomidine 0.5 µg/kg ，completed within 15 minutes.<br>* Other names: Yisi;Drug: Etomidate<br>* After 90 seconds of Pretreatment，intravenous infusion of etomidate fat emulsion 0.3mg/kg. -Does not offer any other drugs within 5 min after completion of etomidate.<br>* Other names: Fuerli;Drug: midazolam，fentanyl，rocuronium<br>* Anesthesia induction：Intravenous injection midazolam 0.03   0.05 mg/kg, fentanyl 5   8 g/kg, rocuronium 0.6 mg/kg<br>* Other names: Liyuexi，Fentanyl Citrate Injection，Aikesong;Drug: propofol，remifentanil，cis atracurium<br>* Anesthesia maintenance：Intravenous infusion of propofol 4   6 mg/kg/h, remifentanil 0.1   0.3 μg/kg/min, intermittent intravenous injection of cis atracurium 0.05   0.1mg/kg<br>* Other names: Propofol Injection，Ruifen，Cisatracurium Besylate Injection;|
| Experimental: High-dose Dexmedetomidine<br>-Pretreatment before anesthesia induction：Intravenous injection dexmedetomidine 1 µg/kg，completed within 15 minutes. | Drug: High-dose dexmedetomidine<br>* Pretreatment：Intravenous injection dexmedetomidine 1 µg/kg ，completed within 15 minutes.<br>* Other names: Yisi;Drug: Etomidate<br>* After 90 seconds of Pretreatment，intravenous infusion of etomidate fat emulsion 0.3mg/kg. -Does not offer any other drugs within 5 min after completion of etomidate.<br>* Other names: Fuerli;Drug: midazolam，fentanyl，rocuronium<br>* Anesthesia induction：Intravenous injection midazolam 0.03   0.05 mg/kg, fentanyl 5   8 g/kg, rocuronium 0.6 mg/kg<br>* Other names: Liyuexi，Fentanyl Citrate Injection，Aikesong;Drug: propofol，remifentanil，cis atracurium<br>* Anesthesia maintenance：Intravenous infusion of propofol 4   6 mg/kg/h, remifentanil 0.1   0.3 μg/kg/min, intermittent intravenous injection of cis atracurium 0.05   0.1mg/kg<br>* Other names: Propofol Injection，Ruifen，Cisatracurium Besylate Injection;|
| Placebo Comparator: normal saline Control group<br>-Pretreatment before anesthesia induction：Intravenous injection normal saline equal quantity，completed within 15 minutes. | Drug: normal saline<br>* Pretreatment：Intravenous injection normal saline equal quantity，completed within 15 minutes.<br>* Other names: Sodium Chloride Physiological Solution;Drug: Etomidate<br>* After 90 seconds of Pretreatment，intravenous infusion of etomidate fat emulsion 0.3mg/kg. -Does not offer any other drugs within 5 min after completion of etomidate.<br>* Other names: Fuerli;Drug: midazolam，fentanyl，rocuronium<br>* Anesthesia induction：Intravenous injection midazolam 0.03   0.05 mg/kg, fentanyl 5   8 g/kg, rocuronium 0.6 mg/kg<br>* Other names: Liyuexi，Fentanyl Citrate Injection，Aikesong;Drug: propofol，remifentanil，cis atracurium<br>* Anesthesia maintenance：Intravenous infusion of propofol 4   6 mg/kg/h, remifentanil 0.1   0.3 μg/kg/min, intermittent intravenous injection of cis atracurium 0.05   0.1mg/kg<br>* Other names: Propofol Injection，Ruifen，Cisatracurium Besylate Injection;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| myoclonus level | Level 0 ：no myoclonus happened; Level 1 ：mild, tiny movement, one part of the body such as a finger or shoulder movement; Level 2 ：moderate ,2 pieces of different muscle or slight movement of the muscle groups, such as face or legs; Level 3 ：severely, 2 pieces or more muscle contracture intensity, such as fast outreach of limbs | when myoclonus occurs after emulsion injection is completed，assessed up to 5 minutes | 
| Plasma homovanillic acid concentration（PHVA） |  | Measured when myoclonus occurs after emulsion injection is completed，assessed up to 5 minutes; if myoclonus does not appear,measured at 5 minutes after emulsion injection is completed. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ramsay sedation score |  | 1 min after entering the operating room; 1 min after dexmedetomidine injection is completed; 1 min after emulsion injection is completed;5 minutes after emulsion injection is completed； | 
| Narcotrend index |  | 1 min after entering the operating room; 1 min after dexmedetomidine injection is completed; 1 min after emulsion injection is completed;5 minutes after emulsion injection is completed； | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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myoclonus, Etomidate, Dexmedetomidine