Remifentanil for the I-gel and Laryngeal Mask Airway Insertion

Study Overview
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Brief Summary
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Structural differences of supraglottic airway devices could influence the different compressive forces in the oropharyngeal cavities, and require different depth of anesthesia. The addition of remifentanil during propofol anesthesia facilitates the insertion of laryngeal mask airway (LMA) with minimal adverse hemodynamic disturbances. This study was designed to determine the effect-site concentration of remifentanil in 50% of patients (EC50) and 95% of patients (EC95) for successful i- gel insertion, and compare those for LMA insertion during propofol target-controlled infusion (TCI).

Detailed Description
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Anesthesia was induced with propofol TCI at the effect-site concentration of 5 μg/ml, and the predetermined effect-site concentration of remifentanil was started simultaneously. The remifentanil concentration was determined using modified Dixon's up-and-down method (initial concentration: 3.0 ng/ml, step size: 0.5 ng/ml). Five minutes later, i- gel or LMA insertion was attempted. The response of the patients to the insertion of LMA was classified as either 'movement' or 'no movement'.

Official Title
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Comparison of the Effect-site Concentration of Remifentanil for Insertion of the I-gel and Laryngeal Mask Airway During Propofol Anesthesia

Conditions
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Supraglottic Airways for General Anesthesia

Intervention / Treatment
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* Drug: remifentanil
* Device: i-gel
* Device: laryngeal mask airway
* Drug: propofol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA I-II patients undergoing general anesthesia for short elective surgery (<2 hr) Exclusion Criteria: G-E reflux obesity (BMI>30) anticipated difficult airway

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 60 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
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: i-gel<br>I-gel insertion was attempted during propofol and remifentanil anesthesia . | Drug: remifentanil<br>* The predetermined effect-site concentration of remifentanil was started using modified Dixon's up-and-down method<br>* Other names: ultiva;Device: i-gel<br>* I-gel insertion was inserted 5 min after anesthesia induction<br>Drug: propofol<br>* Anesthesia was induced with propofol target-controlled infusion at the effect-site concentration of 5 μg/ml<br>* Other names: fresofol;|
| Active Comparator: laryngeal mask airway<br>LMA insertion was attempted during propofol and remifentanil anesthesia . | Drug: remifentanil<br>* The predetermined effect-site concentration of remifentanil was started using modified Dixon's up-and-down method<br>* Other names: ultiva;Device: laryngeal mask airway<br>* laryngeal mask airway insertion was inserted 5 min after anesthesia induction<br>Drug: propofol<br>* Anesthesia was induced with propofol target-controlled infusion at the effect-site concentration of 5 μg/ml<br>* Other names: fresofol;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| successful insertion of i-gel and LMA |  | from 5 min after anesthetic induction to 1min after device insertion |