Administration of Dexmedetomidine Guided by Entropy/SPI Reduce

Study Overview
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Brief Summary
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Dexmedetomidine, a selective alpha2-adrenergic agonist is known to reduce propofol and opioid requirements due to its sedative and analgesic properties. However, until now, there has been studies based on indirect measures such as hemodynamics. Entropy shows to quantify the level of consciousness by EEG and Surgical pleth index(SPI) allows to predict the effect of pain stimuli and analgesic therapy by the index of the nociception-anti-nociception balance. The investigators analyzed quantitatively the requirements of propofol and remifentanil under continuous infusion of dexmedetomidine when using entropy and SPI.

Detailed Description
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Dexmedetomidine, a selective alpha2-adrenergic agonist is known to reduce propofol and opioid requirements due to its sedative and analgesic properties. However, until now, there has been studies based on indirect measures such as hemodynamics. Entropy shows to quantify the level of consciousness by EEG and Surgical pleth index(SPI) allows to predict the effect of pain stimuli and analgesic therapy by the index of the nociception-anti-nociception balance. The investigators analyzed quantitatively the requirements of propofol and remifentanil under continuous infusion of dexmedetomidine when using entropy and SPI. Patients (20 65 years old, ASA class 1 or 2) scheduled lumbar discectomy under general anesthesia were recruited. The patients were randomly allocated to two groups. Both groups received Target controlled infusion(TCI) of propofol and remifentanil and the dexmedetomidine was added to the Dex group and normal saline was added to the Placebo group. The Dex group received 1mcg/kg loading dose followed by 0.5mcg/kg/hr infusion of dexmedetomidine which was administered at induction of anesthesia through skin closure. The placebo group received equal amount of normal saline. During maintenance of anesthesia the effect site concentration of propofol and remifentanil was titrated to maintain Entropy(SE) 40 60 and SPI under 50. Blood pressure and heart rate also was measured. The total amount of propofol and remifentanil administered, time between eye opening and extubation was recorded. The quality of recovery was evaluated by QoR-40 survey after 24 hours postop.

Official Title
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Does Administration of Dexmedetomidine Guided by Entropy/SPI Reduce the Requirement of Propofol and Remifentanil as Well as Increase the Quality of Recovery Profile?

Conditions
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Anesthesia

Intervention / Treatment
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* Drug: Group Dex (dexmedetomidine)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1.The patients (20 65 years old, ASA class 1 or 2) scheduled lumbar discectomy under general anesthesia Exclusion Criteria: ASA class (American Society of Anesthesiologist physical status classification) 3 or higher Patients with history of allergy or side effects on propofol, remifentanil, dexmedetomidine BMI (body mass index) higher than 35 Patients taking monoamine oxidase inhibitor or adrenergic blocking agent Pregnancy, Emergency operation Patients with liver disease, cognitive dysfunction or drug abuse history

Ages Eligible for Study
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Minimum Age: 20 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Group Dex<br>The Dex group received 1mcg/kg loading dose followed by 0.5mcg/kg/hr infusion of dexmedetomidine which was administered at induction of anesthesia through skin closure. Interventions: ◦Drug: Dexmedetomidine | Drug: Group Dex (dexmedetomidine)<br>* 1mcg/kg loading dose followed by 0.5mcg/kg/hr infusion of dexmedetomidine which was administered at induction of anesthesia through skin closure<br>* Other names: Precedex;|
| Placebo Comparator: Group Placebo<br>The Placebo group received equal amount of normal saline. Interventions: ◦Drug: Normal saline | Drug: Group Dex (dexmedetomidine)<br>* 1mcg/kg loading dose followed by 0.5mcg/kg/hr infusion of dexmedetomidine which was administered at induction of anesthesia through skin closure<br>* Other names: Precedex;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The difference of the requirements of propofol and remifentanil between each groups | We analyzed quantitatively the requirements of propofol and remifentanil under continuous infusion of dexmedetomidine or placebo(normal saline) when using entropy and SPI. | the day of surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The difference of quality of recovery between each groups | The quality of recovery was evaluated by QoR-40 survey after 24 hours postop. | 24 hours after surgery |