Effectiveness of Cricoid and Paratracheal Pressures for Occluding Esophagus

Study Overview
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Brief Summary
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Comparing the effects of 'Cricoid pressure' or 'Paratracheal pressure' during direct laryngoscopy

Detailed Description
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The effectiveness of cricoid pressure and paratracheal pressure for occluding esophagus during direct and video laryngoscopies.

Official Title
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Effectiveness of Cricoid and Paratracheal Pressures for Occluding Esophagus in Anesthetized and Paralyzed Patients During the Induction of Anesthesia

Conditions
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Intubation Complication

Intervention / Treatment
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* Other: Maneuvers for occluding esophagus


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Who would be scheduled any surgery under general anesthesia and agree with the purpose of the study Exclusion Criteria: Risk of aspiration History of esophageal surgery Diseases or anatomical abnormalities of the neck, larynx, pharynx or esophagus Known or predicted difficult airway.

Ages Eligible for Study
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Minimum Age: 19 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: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Cricoid pressure<br>Cricoid pressure is applied in the anesthetized state and during video laryngoscopy | Other: Maneuvers for occluding esophagus<br>* Cricoid pressure: pressure on the cricoid ring Paratracheal pressure: pressure on the left paratracheal region below the cricoid level<br>|
| Experimental: Paratracheal pressure<br>Paratracheal pressure is applied in the anesthetized state and during video laryngoscopy | Other: Maneuvers for occluding esophagus<br>* Cricoid pressure: pressure on the cricoid ring Paratracheal pressure: pressure on the left paratracheal region below the cricoid level<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occlusion of the esophagus | Occlusion of the esophagus is checked with the application of cricoid and paratracheal pressures using esophageal stethoscope. If the esophageal stethoscope is not advanced into the esophagus, it is considered 'occlusion'. | During 1 minute under videolaryngoscopy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Outer diameter of the esophagus | Outer diameter of the esophagus is measured using ultrasound before and after the application of cricoid and paratracheal pressures. | During 1 minute after injection of anesthetics during induction of anesthesia | 
| Position of the oesophageal entrance relative to the glottis | Position of the oesophageal entrance relative to the glottis is evaluated. | During 1 minute after injection of anesthetics during induction of anesthesia and during videolaryngoscopy | 
| Position of the upper oesophagus relative to the trachea | Position of the upper oesophagus relative to the trachea trachea is evaluated. | During 1 minute after injection of anesthetics during induction of anesthesia and during videolaryngoscopy | 
| The best laryngeal view | The best laryngeal view is evaluated using the percentage of glottis opening (POGO) score, ranging from 0% to 100%. | Before and after the application of cricoid and paratracheal force during videolaryngoscopy |