Optimal End-Tidal (ET) Sevoflurane and Desflurane Concentration for Extubation of Supreme Laryngeal Mask Airway (LMA) in Adults

Study Overview
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Brief Summary
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The purpose of this study is to determine the optimal volatile anaesthetic (sevoflurane and desflurane) to remove a Supreme LMA in adults in which there is minimal airway response. Null hypothesis: there is no significant difference between the optimal end tidal concentration of sevoflurane and desflurane for Supreme LMA removal.

Detailed Description
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The manufactures' instructions for removal of the LMA recommend waiting until protective reflexes have returned. However, the appropriate timing for removal remains controversial. A more frequent incidence of airway hyperreactivity and complications has been reported by some studies when the LMA was removed in the awake state versus the anesthetized state. Techniques that reduce the time from LMA removal to the return of protective airway reflexes would minimize the risk of aspiration, contamination, or airway obstruction. With increasingly common use of Supreme LMA in anaesthetic practice, a safe and suitable depth for removal of the Supreme LMA requires research. Thus the determination of the optimal end-tidal concentration of commonly used volatile agents ie. Sevoflurane and Desflurane for Supreme LMA removal requires research, both for patient safety and minimising anaesthetic costs in dealing with airway complications.

Official Title
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Optimal End-Tidal Concentration of Sevoflurane and Desflurane for Removal of Supreme Laryngeal Mask Airway in Anaesthetized Adults

Conditions
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Airway Complications

Intervention / Treatment
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* Drug: Sevoflurane
* Drug: Desflurane


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA 1-2 patients Age 18 - 49 years old Elective surgery of short duration ( < 2 hours ) which require local anaesthetic infiltration Exclusion Criteria: Upper respiratory tract symptoms in the previous 10 days Risk of gastric oesophageal reflux or regurgitation Known or predicted difficult airway Poor dentition with high risk of damage BMI > 30 kg/m2 Refusing to participate

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 49 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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sevoflurane<br>1 arm will receive sevoflurane at varying concentrations at which extubation is attempted according to the Dixon up and down method | Drug: Sevoflurane<br>* Comparing the optimal end-tidal concentration sevoflurane and desflurane for LMA extubation<br>|
| Experimental: Desflurane<br>1 arm will receive desflurane at varying end tidal concentration at which extubation will be attempted according to Dixon up and down method | Drug: Desflurane<br>* Comparing the optimal end-tidal concentration sevoflurane and desflurane for LMA extubation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Optimal end tidal concentration of sevoflurane/ desflurane |  | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| presence of airway response |  | 10 mins after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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end tidal concentration