Ultrasound Guided Cricoid and Paralaryngeal Pressure

Study Overview
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Brief Summary
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The primary objective is to study impact of upper airway ultrasonography in guiding anaesthetic assistant into providing accurate cricoid pressure, or both cricoid and paralaryngeal pressure in those with oesophagus deviation, achieving sonographic proven oesophageal occlusion compared to those without ultrasound guidance.

Detailed Description
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All patients consented for the study were having their airway examined via US. Cross sectional sonography of the airway was performed to determine the anatomic relationship of the oesophagus relative to the trachea: before induction of anaesthesia after GA before external airway pressure manoeuvre after GA with external airway pressure manoeuvre. US guided CP was applied on subjects with central oesophagus; CP and PLP were applied on subject with eccentric oesophagus anatomy. PLP was performed by lateral compression on the eccentric oesophagus by fingertips under US guidance. To standardised the application of CP and PLP, only 2 well trained investigators were allowed to performed the CP and PLP, US scan on airway and patient recruitment. The conduct of trial involved 2 investigators where first investigator provide US scan, and second investigator provide compression of CP or PLP using fingertips guided by the instruction of first investigator.

Official Title
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Impact of Ultrasound Guidance on the Performance of Accurate Cricoid and Paralaryngeal Pressure

Conditions
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Ultrasonography, Interventional

Intervention / Treatment
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* Other: paralaryngeal pressure
* Other: cricoid pressure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Elective list Under general anaesthesia Not intubated prior to OT Exclusion Criteria: Below 18 years old Pregnant Neck deformities Previous maxillofacial surgery

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Interventional Model Description: The study is a case-control intervention study, where all and every participant will be both the case and the control of their own.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Centrally located oesophagus post GA<br>Oesophagus remained central after general anaesthesia, cricoid pressure applied by fingertips under ultrasound guidance | Other: cricoid pressure<br>* cricoid pressure by fingertips applied under ultrasound guidance<br>|
| Experimental: Eccentric located oesophagus post GA<br>Oesophagus eccentric located after general anaesthesia, paralaryngeal pressure and cricoid pressure applied by fingertips under ultrasound guidance | Other: paralaryngeal pressure<br>* cricoid pressure with paralaryngeal pressure by fingertips applied under ultrasound guidance<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The number of patients with eccentric oesophagus under general anesthesia, successfully occluded by using cricoid and paralaryngeal pressure. | we are studying the effectiveness of cricoid pressure versus cricoid and paralaryngeal pressure(novel technique) in those patients with eccentric oesophagus under general anaesthesia. We use ultrasound to determined the position of the oesophagus after patient under general anaethesia ( to group them under central oesophagus and eccentric oesophagus) and also to determine the success of oesophagus occlusion. | ultrasound assessment of oesophagus done after general anaesthesia, during application of cricoid pressure, and during application of cricoid and paralaryngeal pressure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The number of patients with central oesophagus under general anesthesia, successfully occluded by using cricoid pressure. | The objective is to study the effectiveness of cricoid pressure in those patients with central oesophagus under general anaesthesia. We use ultrasound to determined the position of the oesophagus after patient under general anaethesia, and also to determine the success of oesophagus occlusion. | ultrasound assessment of oesophagus done after general anaesthesia and during application of cricoid pressure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Anatomy, oesophagus, ultrasound, incidence, cricoid, paralaryngeal