Comparison of Reduced Cuff-pressure of the Laryngeal Tube Under General Anesthesia

Study Overview
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Brief Summary
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Optimization the cuff pressure of the laryngeal tube (LT) in relation of the mechanical ventilation, and the reduction of potential leakage mucosal trauma. Comparison of the tightness of LT between the filling volume specified by the manufacturer (connectors are color coded syringe and blocker), 60cmH₂O, 50cmH₂O, 40cmH₂Ound 30cmH₂O. The measurement of the leakage occurs in ml / kg body weight.

Detailed Description
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The ventilation of both cuffs of the laryngeal tube by using the color coding of syringe and connector is a simple, fast and easy way to stabilize the tube and secure seal against the surrounding tissue. The user of this method has only knowledge of the volume (ml), with which the cuff is vented, but not over the cuff pressure (cmH₂O) itself. Permanently high pressures can cause to a lesions to necrosis in the adjacent tissue, on the other hand, the material of the bulging cuff fits less well the anatomy of the patient, leading to leaks in the breathing circuit. Studies of pediatric anesthesia show that on 40cmH₂O reduces the volume of the leak in the laryngeal mask airway by reducing the cuff pressure and the ventilation is improved in sequence. In the proposed study, the volume of leakage at the fill volume specified by the manufacturer (color coding), 60cmH₂O, 50cmH₂O, 40cmH₂O and 30cmH₂O to be captured.

Official Title
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Comparative Study of the Tightness of the Laryngeal Tube Under Mechanical Ventilation Before and After Reduction of Cuff Pressure on 60cmH₂O, 50cmH₂O, 40cmH₂O or 30cmH₂O

Conditions
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Airway Morbidity

Intervention / Treatment
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* Device: Reduce Cuff pressure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 Years No concurrent participation in another study capacity to consent Present written informed consent of the research participant Elective surgery under general anesthesia Height> 150cm Exclusion Criteria: Age <18 years Existing pregnancy Lack of consent inability to consent emergency patients Emergency situations in the context of a Difficult Airway Management ASA classification> 3 situations where the possibility of accumulated gastric contents Indications for intubation with endotracheal tube Height <150cm Participation in another study

Ages Eligible for Study
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Minimum Age: 18 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: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Reduce Cuff Pressure<br>Cuff Pressure difference between inspiration and expiration is measured. | Device: Reduce Cuff pressure<br>* We reduce the Cuff Pressure from the LTS-D (Laryngeal Tube suction) from 60 to 50 to 40 to 30cmH2O and measure the Delta from Inspiration to Expiration Tidalvolume (Delta Vt). The Delta Vt shows the actual leakage.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparison of Leakage between the different Cuff Pressure | We want to measure the tightness of the reduced Cuff Pressure | < 5 Minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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laryngeal tube, cuff pressure, leakage, laryngeal mask