A Comparison of the Intubating Laryngeal Mask FASTRACH™ and the Intubating Laryngeal Mask Ambu Aura-i™

Study Overview
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Brief Summary
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The intubating laryngeal mask Fastrach™ is considered a gold standard for blind intubation as well as for fibreoptic guided intubation via a laryngeal mask. Recently, a single use version of the mask has been introduced. The Fastrach single use laryngeal mask is beng compared to the new, low-priced single use intubating laryngeal mask Ambu Aura-i™.

Detailed Description
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Eighty patients undergoing general anaesthesia with planned tracheal intubation for elective surgical procedures are enrolled in the study after checking for inclusion and exclusion criteria. Patients are randomised to either LMA group for blind tracheal intubation with either a standard PVC tracheal tube, or a specifically for the LMA Fastrach developed tube, yielding 4 subgroups. After a standardised anaesthesia induction, blind intubation is performed in each study group. Different time intervals are documented, such as time to first adequate lung ventilation, or f.e. time for laryngeal mask placement. A crossover-design is performed after unsuccessful intubation, using the alternate LMA or the other tracheal tube. LMA placement is visualised by fibreoptic control. An estimated success rate for blind intubation of 60% in the Aura-i group versus 90% in the Fastrach group yields a sample size of n= 38. To compensate for dropouts, n=40 subjects are enrolled in each group.

Official Title
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A Comparison of the Intubating Laryngeal Mask FASTRACH™ and the Intubating Laryngeal Mask Ambu Aura-i™

Conditions
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Airway Management, Laryngeal Mask Airway, Fibreoptic Intubation

Intervention / Treatment
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* Device: Crossover Ambu Aura-i™ / Rüsch Super Safety Silk™
* Device: Crossover Ambu Aura-i™ / LMA ETT™
* Device: Crossover FASTRACH™ / Rüsch Super Safety Silk™
* Device: Crossover FASTRACH™ / LMA ETT™


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing planned general anaesthesia planned tracheal intubation elective surgical procedure 15 to 80 years of age Exclusion Criteria: ASA physical status IV and V severe pulmonary comorbidity (COPD GOLD >III, bronchial asthma) indication for rapid-sequence induction mouth opening (interincisor distance) <3cm morbid obesity (BMI >35kg.m-2)

Ages Eligible for Study
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Minimum Age: 15 Years
Maximum Age: 80 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: Device Feasibility
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Aura-i / Rüsch<br>Blind tracheal intubation: Combination of laryngeal mask Ambu Aura-i™ with Rüsch Super Safety Silk™ tracheal tube | Device: Crossover Ambu Aura-i™ / Rüsch Super Safety Silk™<br>* After unsuccessful blind intubation in the Ambu Aura-i™ / Rüsch Super Safety Silk™ group: crossover design using the Ambu Aura-i™ mask in combination with the LMA ETT™ tracheal tube<br>|
| Experimental: Aura-i / LMA ETT<br>Blind tracheal intubation: Combination of laryngeal mask Ambu Aura-i™ with LMA ETT™ tracheal tube | Device: Crossover Ambu Aura-i™ / LMA ETT™<br>* After unsuccessful blind intubation in the Ambu Aura-i™ / LMA ETT group: crossover design using the Ambu Aura-i™ mask in combination with the Rüsch Super Safety Silk™ tracheal tube<br>|
| Experimental: Fastrach / Rüsch<br>Blind tracheal intubation: Combination of laryngeal mask Fastrach™ with Rüsch Super Safety Silk™ tracheal tube | Device: Crossover FASTRACH™ / Rüsch Super Safety Silk™<br>* After unsuccessful blind intubation in the FASTRACH™ / Rüsch Super Safety Silk™ group: crossover design using the FASTRACH™ mask in combination with the LMA ETT™ tube<br>|
| Experimental: Fastrach / LMA ETT<br>Blind tracheal intubation: Combination of laryngeal mask Fastrach™ with LMA ETT™ tracheal tube | Device: Crossover FASTRACH™ / LMA ETT™<br>* After unsuccessful blind intubation in the FASTRACH™ / LMA ETT™ group: crossover design using the FASTRACH™ mask in combination with the Rüsch Super Safety Silk™ tube<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| success rate of blind intubation | overall success rate of blind tracheal intubation within two attempts using either the FASTRACH™ laryngeal mask or the Ambu Aura-i™ laryngeal mask | through study completion; time frame for individual study patient: two attempts of blind tracheal intubation peri-interventional, time maximum of 300 seconds | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| influence of tracheal tubes | influence of success rates of blind tracheal intubation using different tracheal tubes (Rüsch or LMA-ETT) | through study completion; time frame for individual study patient: two attempts of blind tracheal intubation peri-interventional, time maximum of 300 seconds | 
| equivalence of the laryngeal masks regarding fibreoptic visualisation | fibreoptic control of laryngeal mask placement (Fastrach and Aura-i); the position of the larynx relative to the laryngeal cuff and mask-aperture is visualised and categorised as correct, lateral deviation, epiglottic downfolding or not assessable; additionally, the view on the larynx comparable to Cormack/Lehane score is recorded | through study completion; after placing the laryngeal mask and checking for airway leak pressure, fibreoptic visualisation is performed within 60 seconds | 
| subjective handling score | subjective handling score for the two compared laryngeal masks, rated as excellent (1) - poor (4) | through study completion; the handling of the laryngeal masks during the first placement attempt within 60 seconds; directly after placing laryngeal masks and before fibreoptic visualisation, the subjective handling score is documented as above | 
| differences in airway leak pressure | differences in airway leak pressure (ALP) of the two compared laryngeal masks, in cm H2O; presence of audible leakage as well as the absence of corresponding pressure increase on the monitor recorded by setting the APL valve to 40cm H2O, and fresh gas flow at 3l/min | through study completion; right after placing the laryngeal mask and checking for correct positioning, ALP is documented within 60 seconds | 
| incidence of postoperative sore throat and hoarseness | incidence of postoperative sore throat and hoarseness as well as difficulty swallowing as reported by the study patients (none, moderate, severe) | patient interview 24 hours post procedural |