The Effect of Placement of Proseal Laryngeal Mask Airway With C-Mac Videolaryngoscopy

Study Overview
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Brief Summary
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The ProSeal laryngeal mask airway (ProSeal LMA; Intavent Orthofix, Maidenhead, UK) is a device with a double cuff to improve the seal and a drain tube to help prevent aspiration and gastric insufflation, facilitate passage of a gastric tube, and provide information about malposition. The manufacturer recommends inserting the ProSealTM LMA using digital manipulation or with an introducer tool, but both these techniques have lower success rates than the classic LMA. This prospective study that will investigated the usefulness of the C-MAC videolaryngoscopy for inserting a PLMA in anesthetized non-paralyzed patients and compared it with the index finger.

Detailed Description
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Airway management is one of the cornerstones for modern anaesthesia and is vital for all patients undergoing general anaesthesia. Supraglottic airway devices (SADs) are increasingly used for managing airways. The ProSeal laryngeal mask airway (PLMA) (Laryngeal Mask Company, San Diego, CA, USA) is a supraglottic airway device with a larger cuff than the Classic laryngeal mask airway to produce a better seal. The PLMA is also equipped with a drainage tube to permit insertion of a gastric tube and evacuation of gastric content. The presence of the drainage tube reduces the risk of aspiration, which is the major concern of the Classic laryngeal mask airway, especially when the device is used with positive pressure ventilation. While a dedicated introducer (commonly known as an ''introducer tool'') is recommended by the manufacturer to facilitate insertion of the PLMA, difficulties can still be encountered during insertion. The PLMA insertion success rate at first attempt has been reported as 82-87%, which is lower than the insertion success rate of the Classic laryngeal mask airway. Malpositioning of the PLMA is common in clinical practice because its soft cuff can fold over onto itself. Malpositioning of the device can result in severe leaks and even obstruction of the airway, with potentially negative outcomes for the patient. Although the incidence of complications(e.g. airway trauma, obstruction, regurgitation, gastric distension with mechanical ventilation) is likely to be higher with an incorrectly placed SAD, clinical airway obstruction can result from other causes, such as laryngospasm and transient closure of the glottis. Many methods have been proposed to facilitate insertion of PLMAs, including insertion of a gastric tube,a suction catheter, or a gum elastic bougie into the drainage tube. These techniques help to prevent the PLMA soft cuff from folding over and help to decrease the incidence of malpositioning. This prospective study that will investigated the usefulness of the C-MAC videolaryngoscopy for inserting a PLMA in anesthetized non-paralyzed patients and compared it with the index finger.

Official Title
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Comparison of C-MAC Videolaryngoscopy-guided Proseal Laryngeal Mask Airway Placement vs Conventional Blind Technique: a Prospective Randomized Study

Conditions
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Laryngeal Masks, Anesthesia, General, Videolaryngoscopy

Intervention / Treatment
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* Device: C-MAC videolaryngoscope
* Device: Blind


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18- 65 years Undergoing short surgical prcedures with general anesthesia using a PLMA American Society of Anesthesiology score I-II Exclusion Criteria: Anticipated difficult airway Risk of aspiration Patients who refused written informed consent forms

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Screening
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: C-MAC Videolaryngoscope<br>C-MAC Videolaryngoscope: An intubating device that is used for endotracheal intubation. Proseal laryngeal mask airway will be inserted with C-MAC Videolaryngoscope | Device: C-MAC videolaryngoscope<br>* An intubating device that is used for endotracheal intubation. PLMA will inserted by anesthesiologist with C-MAC videolaryngoscope.<br>|
| Active Comparator: Blind<br>Proseal laryngeal mask airway will be inserted with digital finger | Device: Blind<br>* PLMA will inserted by anesthesiologist with digital finger.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| First attempt success rate | The PLMA will inserted into hypopharynx, the cuff will inflated with an appropraite volume of air. An effective airway will judged by a square wave on capnography. | From inserted PLMA to seeing meaningful end-tidal carbon dioxide levels up to 2 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Insertion time | Insertion time was the time between picking up the PLMA and successful placement | From inserted PLMA to seeing two meaningful end-tidal carbon dioxide levels up to 3 minutes | 
| Adverse Events | Blood on the surface of the cuff, laryngospasm, hypoxia, hoarseness,sore throat | During the first 24 hour postoperatively | 
| Fiberoptic Score | Fiberoptic view of PLMA placement through the airway tube was graded on a scale from 4 (best view) to 1 (worst view) | After the PLMA insertion up to 5 minutes | 
| Airway Sealing Pressure | Fresh gas flow was adjusted to 3 L/min, and after closing the expiratory valve, the airway pressure at which an audible leak in the mouth was heard will recorded | After the PLMA insertion up to 5 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Airway management, Videolaryngoscopy, General anesthesia