Preoxygenation Using High Flow Oxygen : Efficacy and Tolerance in Healthy Volunteers

Study Overview
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Brief Summary
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High flow nasal cannula oxygen has been proposed to perform preoxygenation in patients with acute respiratory failure requiring orotracheal intubation in intensive care units. However, its use for preoxygenation before the induction of general anaesthesia in operating room has never been evaluated in term of end tidal oxygen fraction which is the gold standard measurement during preoxygenation before general anaesthesia. The goal of the present study is to measure end tidal oxygen after 3 min of preoxygenation using the recommended method (spontaneous breathing of 100% inhaled oxygen through a face mask) and using high flow nasal canula oxygen, in healthy volunteers.

Detailed Description
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High flow nasal cannula oxygen has been proposed to perform preoxygenation in patients with acute respiratory failure requiring orotracheal intubation in intensive care units. The results suggest that high flow oxygen could be superior to bag reservoir face mask in term of occurrence of severe hypoxemia during the intubation procedure. At the present time its use for preoxygenation before the induction of general anaesthesia in operating room has never been evaluated in term of end tidal oxygen fraction which is the gold standard measurement ensuring that the functional residual capacity has been filled with oxygen. We planned a randomised cross over study in healthy volunteers studying efficacy and tolerance of preoxygenation using spontaneous ventilation with 100% inhaled oxygen through a face mask connected to the anaesthesia machine and preoxygenation using high flow nasal cannula oxygen (60l/min).

Official Title
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Comparison of Efficacy and Tolerance of Preoxygenation Using High Flow Oxygen and Face Mask Breathing in Healthy Volunteers.

Conditions
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Anesthesia, Airway Morbidity, Safety Issues

Intervention / Treatment
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* Procedure: preoxygenation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy volunteers, signed contentment Exclusion Criteria: any chronic or acute disease, pregnancy

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: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: control<br>spontaneous breathing through a face mask connected to the anaesthesia machine delivering 100% oxygen gas flow (15l/min) | Procedure: preoxygenation<br>* spontaneous breathing<br>|
| Experimental: ohd<br>spontaneous breathing through a nasal cannula connected to an humidifier device delivering warm (37°C) high flow oxygen(60l/min) | Procedure: preoxygenation<br>* spontaneous breathing<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| FeO2 at 3 min | end tidal oxygen fraction measured through a gas analyser | 3 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| time to obtain an FeO2 at 90% | time to obtain an end tidal oxygen fraction measured at 90% measured through a gas analyser | 6 minutes | 
| proportion of adequate preoxygenation at 3 min | proportion of adequate preoxygenation (FeO2=90%) at 3 min | 6 minutes | 
| tolerance | self reported tolerance on a likert scale | 1 hour | 
| tolerance on VAS | self reported tolerance on a visual analogue scale | 1 hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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preoxygenation, high flow oxygen