Patient Positions for Locating the Cricothyroid Membrane

Study Overview
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Brief Summary
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Cricothyroidotomy is an emergency rescue technique to secure the airway in a 'Can't intubate, Can't Oxygenate' (CICO) situation. The cricothyroid membrane (CTM) is the target site of cricothyroidotomy, and accurate identification of the CTM is essential for successful cricothyroidotomy. In this study, the investigators compare patient positions (neck extension vs. modified ramped position) in terms of the success rate for identifying the CTM in obese patients.

Official Title
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Comparison of Patient Positions for Locating the Cricothyroid Membrane

Conditions
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Cricothyroid Membrane

Intervention / Treatment
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* Other: Identification of the cricothyroid membrane


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: body mass index >30 kg/m2 Exclusion Criteria: anatomical abnormalities or pathologies of the neck or larynx a history of neck surgery.

Ages Eligible for Study
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Minimum Age: 19 Years

Sexes Eligible for Study
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Female

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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Neck extension group<br>The cricothyroid membrane is identified in a neck extended position. | Other: Identification of the cricothyroid membrane<br>* The cricothyroid membrane is identified using a laryngeal handshake technique in different patient positions.<br>|
| Experimental: Modified ramped position group<br>The cricothyroid membrane is identified in a modified ramped position. | Other: Identification of the cricothyroid membrane<br>* The cricothyroid membrane is identified using a laryngeal handshake technique in different patient positions.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Success rate for the correct identification of the cricothyroid membrane | After identifying the cricothyroid membrane using a laryngeal handshake technique in different head positions, an assessor evaluates the correctness of its localization using ultrasound. | Immediately after identifying the cricothyroid membrane using a laryngeal handshake technique | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Duration for identifying the cricothyroid membrane | Time taken to locate the cricothyroid membrane is checked. | At 90 seconds after administering neuromuscular blockade | 
| Distances between the center of the actual and perceived cricothyroid membrane | Distances between the center of the actual and perceived cricothyroid membrane is measured using ultrasound. | Immediately after identifying the cricothyroid membrane using a laryngeal handshake technique | 
| Perceived difficulty during cricothyroid membrane identification | Anatomical difficulty perceived by the anesthesiologists during cricothyroid membrane identification is assessed (1, very easy; 2, easy; 3, moderate; 4, difficult; and 5, very difficult). | At 5 minutes after identifying the cricothyroid membrane using a laryngeal handshake technique |