Determine the ED50 of Dexmedetomidine to Facilitate LMA Insertion During Anaesthesia Induction

Study Overview
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Brief Summary
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Dexmedetomidine can be used as a co-induction agent to facilitate laryngeal mask airway (LMA) insertion with minimal effect on respiratory function. The purpose of the study was to determine the median effective dose (ED50) of dexmedetomidine to facilitate LMA insertion during anaesthesia induction with propofol 2.0 mg/kg.

Detailed Description
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Dexmedetomidine is a highly selective α2 receptor agonist, which produces sedative, anxiolytic and analgesic effects without causing clinically significant respiratory depression. Dexmedetomidine also reduces the propofol requirement for sedation and anaesthesia induction. Therefore, dexmedetomidine may be a useful co-induction agent to facilitate LMA insertion with minimal effects on respiratory function. A recent study showed that dexmedetomidine administration prior to propofol induction provided similar conditions for successful LMA insertion, as does fentanyl without respiratory depression. The purpose of this study was to determine the median effective dose (ED50) of dexmedetomidine required for successful LMA insertion during induction with propofol of 2 mg/kg .

Official Title
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To Determine the Median Effective Dose (ED50) of Dexmedetomidine to Facilitate LMA Insertion During Anaesthesia Induction With Propofol 2.0 mg/kg

Conditions
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Anesthesia

Intervention / Treatment
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* Drug: Dexmedetomidine
* Drug: Propofol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA Ⅰ   Ⅱ women undergoing Laparoscopic surgery. Written informed consent from the patient or the relatives of the participating patient. BMI:18.5～25 Exclusion Criteria: Mental illness can not match epidural anesthesia contraindicated People who have Slow-type arrhythmias Chronic renal failure Alcohol or drug abuse Already taking gabapentin, pregabalin, benzodiazepin or antidepression drug

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

Sexes Eligible for Study
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Female

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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dexmedetomidine<br>After an injection of pre-determined bolus dose of dexmedetomidine over 10 min, anaesthesia was induced with propofol 2.0 mg/kg. The modified Dixon's up-and-down method was used to determine the bolus dose of dexmedetomidine, starting from 1.0μg/kg (step size; 0.1μg/kg). | Drug: Dexmedetomidine<br>* The modified Dixon's up-and-down method was used to determine the bolus dose of dexmedetomidine, starting from 1.0μg/kg (step size; 0.1μg/kg)<br>Drug: Propofol<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The assessment of sedation (determine the effect-site dose of dexmedetomidine blunting cardiovascular responses to the insertion of the laryngeal mask airway at the same level of sedation) | The aim of this study was to determine the effect-site dose of dexmedetomidine blunting cardiovascular responses to the insertion of the laryngeal mask airway at the same level of sedation. | 5min after the end of the infusion | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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laryngeal mask airway, circulatory reflexes