Ambu®AuraGain™ Versus I-gel® in Obese Patients

Study Overview
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Brief Summary
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The aim of this study is the randomized comparison of two laryngeal mask (Intersurgical i-gel® and Ambu®AuraGain™) in obese patients

Detailed Description
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Since the incidence of a difficult intubation lies between 4.5% -7.5%, the search for alternative airway devices has been forced in the past. As an option, the laryngeal mask is suitable, which has been used as a universal airway with a high degree of safety in routine anesthesia. There are numbers of different laryngeal masks available which have the characteristic to insert an endotracheal tube through the ventilation lumen. The indications for these laryngeal masks can be extended due to continuous improvements in the laryngeal masks, these laryngeal masks can also be used in obese patients. Obese patients generally have a 4-fold increased risk of a difficult airway, and a BMI over 35 is a predictor of a difficult tracheal intubation. There are no studies comparing the Intersurgical i-gel® Laryngeal Mask and the Ambu®AuraGain ™ Laryngeal Mask in obese patients.

Official Title
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Prospective Randomized Comparison Between a Fiber Optic Intubation Via the Ambu® AuraGain ™ or the i-Gel® Laryngeal Mask Until a Complete Airway Protection in Obese Patients

Conditions
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Obese

Intervention / Treatment
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* Device: Ambu AuraGain
* Device: Intersurgical i-gel


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA 1-3 Shoulder-/Elbow-/Hip-/Knee- or Foot - Surgery Signed informed consent BMI > 35kg/m2 Exclusion Criteria: Non-sober patients (last meal <6 h) Symptomatic reflux disease Hiatus hernia Significant cardiovascular risk factors Severe COPD Gastric band or gastric bypass Disease which allows an accurate examination of the physicians (e.g. neuromuscular, mental, metabolic disease) Drug or drug abuse in the recent past Legal immaturity (incompetence) Acute disease, which calls into question the narcotic potential Patients with whom the use of a laryngeal mask is contraindicated or otherwise not possible

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Ambu® AuraGain™<br>Intervention with Ambu® AuraGain™Laryngeal Mask | Device: Ambu AuraGain<br>* Insert and intubation of an Ambu® AuraGain™ laryngeal mask<br>|
| Active Comparator: Intersurgical i-gel®<br>Intervention with Intersurgical i-gel® Laryngeal Mask | Device: Intersurgical i-gel<br>* Insert and intubation of an Intersurgical i-gel®<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time of successful intubation | Measurement of a fiberoptic intubation with the laryngeal mask. Start: Insertion of the fiberoptic into the larynxmask until the intubation has been done and after the fiberoptic has been removed. | intraoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Insertions (of the laryngeal mask) | Number of insertion attempts will be registered | intraoperative | 
| Time of insertion | The time of Insertion of the laryngeal mask will be recorded. | intraoperative | 
| Number of insertion attempts | Number of insertions with the stomach tube will be registered | intraoperative | 
| Gastric volume | Measurement of the gastric volume | intraoperative | 
| Positioning of the gastric probe | Determination of the position of the gastric probe after successful insertion by stethoscope. | intraoperative | 
| Successful Ventilation | Detection of a successful Ventilation. There are two options: a tidal volume > 6mL/kg lean body mass or endtidal pCO2 < 6.7kPa | intraoperative | 
| Oropharyngeal leak pressure of the Ambu®AuraGain ™ | The oropharyngeal leak pressure of the AuraGain™ is measured with a measured cuff volume of 60cmH2O | intraoperative | 
| Oropharyngeal leak pressure of the Intersurgical i-gel® | The oropharyngeal leak pressure of the Intersurgical i-gel® is measured. | intraoperative | 
| Measurement of blood pressure | Measurement of blood pressure during 5min (1 measurement / minute). | intraoperative | 
| Measurement of oxygen saturation | Measurement oxygen saturation during 5min (1 measurement / minute). | intraoperative | 
| Measurement of heart rate | Measurement of heart rate during 5min (1 measurement / minute). | intraoperative | 
| Maximum ventilation pressure | The maximum ventilation pressure is measured, which must be applied in order to adequately ventilate the patients. This is measured over 5 minutes | intraoperative | 
| Measurement CO2 (kPa): | The exhaled CO2 is determined continuously. | intraoperative | 
| Number of intubation attempts | The number of intubation attempts until successful intubation is recorded. | intraoperative | 
| Reasons for the unsuccessful intubation | The reasons are listed in tabular form. | intraoperative | 
| Number of esophageal intubations | The number of esophageal intubations is measured. | intraoperative | 
| Resistance (for an EET): | The resistance is measured with a score of 1- 4. 1: simple passage, no resistance, 2: little resistance for the passage, 3: significant resistance for the passage, 4: passage not possible | intraoperative | 
| Location of the mask (Brimacombe) | The position of the mask is determined by pushing the fiber optic to a maximum of 1cm over the LMA and then using the Brimacombe score. | intraoperative | 
| Swallowing (no / little / medium / strong) | The swallowing difficulties are questioned preoperatively and postoperatively (5 (± 1) h after anesthesia end). | 5hour postoperative | 
| Throat pain (no / little / medium / strong) | The throat pain is questioned preoperatively and postoperatively (5 (± 1) h after anesthesia end). | 5hour postoperative | 
| Hoarseness (no / little / medium / strong) | The swallowing difficulties, the throat pain and the hoarseness are questioned preoperatively and postoperatively (5 (± 1) h after anesthesia end). | 5hour postoperative | 
| Blood on laryngeal mask after intubation | Determination of the visible blood on the laryngeal mask after removal (no, little, much). | intraoperative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Obese, Laryngeal Mask Airway, Anaesthesia