The Ratio of Hypnotic to Analgesic Potency of Volatile Anesthetics

Study Overview
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Brief Summary
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The aim of this clinical trial is to evaluate the ratio of hypnotic to analgesic potency of sevoflurane and desflurane at equi-minimum alveolar concentration using SPI and EEG analysis.

Detailed Description
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Anesthetic agents vary in their relative hypnotic potency. Recent studies demonstrated that equi-minimum alveolar concentration of various volatile anesthetic agents may produce different spectral entropy or bispectral index values. However, there is no study that demonstrate the difference between analgesic potency of volatile anesthetics. The aim of this clinical trial is to evaluate the ratio of hypnotic to analgesic potency of sevoflurane and desflurane at equi-minimum alveolar concentration using SPI and EEG analysis.

Official Title
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The Ratio of Hypnotic to Analgesic Potency of Sevoflurane and Desflurane : Randomized Controlled Trial

Conditions
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Anesthesia, General

Intervention / Treatment
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* Drug: Sevoflurane
* Drug: Desflurane


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing general anesthesia using volatile anesthetics and supraglottic airway (I-gel™) patients with american society of anesthesiologist physical status I, II patients aged 19-65 years patients obtaining written informed consent Exclusion Criteria: patients with a history of any psychiatric or neurological disease patients who had received any medication affecting the central nervous system patients who had received medication affecting the sympathetic or parasympathetic nervous systems patients undergoing tracheal intubation for airway management pregnant women

Ages Eligible for Study
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Minimum Age: 19 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 |
| --- | --- |
| Experimental: Sevoflurane<br>Anesthesia was maintained with sevoflurane. | Drug: Sevoflurane<br>* Anesthesia was maintained with sevoflurane in patients undergoing standardized nociceptive stimulus (long-lasting tetanic stimulus of the ulnar nerve; 30 s, 50 mA, 50 Hz, square-wave).<br>* Other names: SEVO;|
| Experimental: Desflurane<br>Anesthesia was maintained with desflurane. | Drug: Desflurane<br>* Anesthesia was maintained with desflurane in patients undergoing standardized nociceptive stimulus (long-lasting tetanic stimulus of the ulnar nerve; 30 s, 50 mA, 50 Hz, square-wave).<br>* Other names: DES;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Surgical pleth index | The analgesic potency of volatile anesthetics was evaluated by surgical pleth index during standardized nociceptive stimulus (30 s, 50 mA, 50 Hz tetanic stimulation). | the 10 min at steady-state anesthesia after endotracheal intubation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bispectral index | The hypnotic potency of volatile anesthetics was evaluated by bispectral index during standardized nociceptive stimulus (30 s, 50 mA, 50 Hz tetanic stimulation). | the 10 min at steady-state anesthesia after endotracheal intubation |