Head Position for Laryngeal Mask Air Leak and Performance in Paediatric Patients (Neutral, Sniffing and Beyond Sniffing Position)

Study Overview
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Brief Summary
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The correct head position for airway management is considered as a mainstay of good clinical practice. The recommended head position for all patients is the horizontal position of the head with in tragus-to- sternal notch in line alignment. This could be achieved in infant (under two years) supporting the shoulder, neutral head positioning in children between 2-8 (12) years and with so called sniffing position (SP) in patients over 12 year by supporting the head (i.e. with pillow) to reach the proper alignment (tragus to sternal notch). Although, this could be considered as gold standard, there are currently insufficient high quality evidence-based data to confirm the association between the better laryngeal view during the direct laryngoscopy and tragus-to-sternal notch position. Recently, beyond sniffing position was described as further head elevation (compared to sniffing position) in adult patients. Beyond sniffing position was associated with superior laryngeal inlet visualization compared to standard sniffing position in common elective adult airway management (patients with suspected or confirmed difficult airway was excluded). The hypothesis of SNIFF LM trial is that the sniffing position or even beyond sniffing position could be associated with superior laryngeal mask performance (lower incidence of air leak, LM easier introduction) compared neutral position in paediatric patients undergoing elective paediatric anaesthesia

Detailed Description
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Paediatric patients (between 2-18 years) undergoing elective airway management without predicted/confirmed difficult airway will be eligible for inclusion. The patients will be screened for eligibility during the preanaesthesia visit in anaesthesiology examination room. After informed consent the patients will be randomized into 3 groups (according to the induction head position) - neutral head position (without head elevation, head supported with the hollow foam circle to prevent side head movement), sniffing position (head support with inflatable pillow the reach the horizontal in-line alignment of tragus-to-sternal notch line) and beyond sniffing position (further 25% increase of head support compared to sniffing position). The randomization will be performed by the Institute of Biostatistics and Analysis in form of sealed envelopes. The group allocation will be 1:1:1. After fulfilling the inclusion criteria and obtaining the informed consent the patient will be randomized into 3 groups. Before anaesthesia induction the head of the patient will be positioned into the predefined position according to the results of randomization. The anaesthesia induction could be performer either inhalation or intravenous route. After anaesthesia induction, the laryngeal mask will be inserted in the selected position. After laryngeal mask insertion, stabilisation of vital signs and of anaesthesia depth, the measurement will be intiated within 5 minutes. After one minute of ventilation 3 leak volumes (inspiration - expiration tidal volume) together with the peak airway pressure (3 measurements) will be recorded (the mean volume and mean pressure will be analyzed). Patient´s head will be repositioned into the 2nd position and after one minute of ventilation leak volume and airway pressure will be recorded as previously described, after measurement, the head position will be repositioned into the 3rd positon and the measurement will be repeated. The incidence of 1st insertion attempt failure rate, incidence of laryngeal mask failure rate, incidence of the need for reposition will be recorded together with the incidence of airway related complications.

Official Title
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Head Position for Laryngeal Mask Air Leak and Performance in Paediatric Patients (Neutral, Sniffing and Beyond Sniffing Position): Prospective Randomized Trial

Conditions
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Airway Management

Intervention / Treatment
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* Device: Laryngeal mask insertion
* Device: Laryngeal mask insertion
* Device: Laryngeal mask insertion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 2-19 years Informed consent Elective airway management laryngeal mask for airway management Exclusion Criteria: Outside the age limits Decline to participate Predicted or confirmed difficult airway Cervical spine injury limited access to head of the patient after anaesthesia induction (for the measuement purposes) Intubation

Ages Eligible for Study
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Minimum Age: 2 Years
Maximum 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: Treatment
Allocation: Randomized
Intervention Model: Single Group Assignment
Interventional Model Description: Paediatric patients (between 2-18 years) undergoing elective airway management without predicted/confirmed difficult airway with the laryngeal mask airway after anaesthesia induction
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Neutral head position<br>Laryngeal mask will be inserted after anaesthesia induction in neutral head position | Device: Laryngeal mask insertion<br>* Laryngeal mask insertion in neutral position<br>Device: Laryngeal mask insertion<br>* Laryngeal mask insertion in sniffing position<br>Device: Laryngeal mask insertion<br>* Laryngeal mask insertion in beyond sniffing position<br>|
| Active Comparator: Sniffing position<br>Laryngeal mask will be inserted after anaesthesia induction in sniffing head position | Device: Laryngeal mask insertion<br>* Laryngeal mask insertion in neutral position<br>Device: Laryngeal mask insertion<br>* Laryngeal mask insertion in sniffing position<br>Device: Laryngeal mask insertion<br>* Laryngeal mask insertion in beyond sniffing position<br>|
| Experimental: Beyond sniffing position<br>Laryngeal mask will be inserted after anaesthesia induction in sniffing head position | Device: Laryngeal mask insertion<br>* Laryngeal mask insertion in neutral position<br>Device: Laryngeal mask insertion<br>* Laryngeal mask insertion in sniffing position<br>Device: Laryngeal mask insertion<br>* Laryngeal mask insertion in beyond sniffing position<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| leak volume in 3 different head position in every patient (1st position will be randomized) | leak volume in 3 different head position in every patient (1st position will be randomized) defined by the average leak obtained from 3 measurements in selected position | 1 minute mechanical ventilation in predefined head position | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Leak pressure in 3 different head position in every patient (1st position will be randomized) | Leak pressure in 3 different head position in every patient (1st position will be randomized) defined by the first audible leak during stepwise increasing inspiratory pressure | 1 minute mechanical ventilation in predefined head position | 
| incidence of failed 1st attempt insertion rate | incidence of failed 1st attempt insertion rate | anaesthesia induction | 
| incidence of overall laryngeal mask failure | incidence of overall laryngeal mask failure | anaesthesia induction | 
| incidence of the need for head reposition to obtain better airway seal in the 3 randomized head positions. | incidence of the need for head reposition to obtain better airway seal in the 3 randomized head positions | Intraoperatively | 
| Incidence of airway related complication | Incidence of airway related complication -regurgitation/aspiration, desaturation, oesophageal intubation, laryngeal/airway injury incidence | From anaesthesia induction until dismission from postanaesthesia care unit | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Supraglottic Airway Devices, Laryngeal mask airway, Head position, Paediatric patient