Inspiratory Support Improves Preoxygenation in Healthy Subjects

Study Overview
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Brief Summary
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Preoxygenation optimizes oxygen content in the functional residual capacity (FRC). Adequate preoxygenation is defined by an expiratory oxygen fraction (FEO2) > 90%. Inspiratory support and positive end expiratory pressure (PEEP) can create a better reservoir, improve gas exchange and shorten the time needed for adequate preoxygenation. The goal of the study is to evaluate the efficacy and tolerability of different levels of inspiratory support and positive end expiratory pressure during preoxygenation in healthy subjects.

Detailed Description
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We conducted a double blind prospective randomized trial on 20 healthy volunteers. Each subject went through three modes of preoxygenation in random order: normal breathing (SP), breathing under inspiratory support 4 cmH2O/PEEP 4 cmH2O (PSM-4) and inspiratory support 6 cmH2O /PEEP 4 cmH2O (PSM-6). Each mode lasted for 3 min and parameters were recorded every 10 s. We evaluated subject's tolerance, leaks and easiness of each mode of preoxygenation according to a simplified (1 to 4) scale. Two-way ANOVA was used to compare FEO2 while simple ANOVA was used for time to reach FEO2=90%.

Official Title
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The Efficacy and Tolerability of Different Levels of Inspiratory Support and PEEP During Preoxygenation. A Randomized Controlled Trial.

Conditions
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Healthy

Intervention / Treatment
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* Other: VS
* Other: AI-4/PEEP-4
* Other: AI-6/PEEP-4


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy volunteers Aged between 20 to 40 years Exclusion Criteria: Body mass index > 30 Mustache, beard Claustrophobia

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 40 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

Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: BiPAP6 assisted preoxygenation<br> | Other: AI-6/PEEP-4<br>* Spontaneous breathing of 100% oxygen in a facemask with application of an inspiratory pressure of 6 cm H2O and a positive end-expiratory pressure of 4 cm H2O, for 3 minutes.<br>|
| Active Comparator: BiPAP4 assisted preoxygenation<br> | Other: AI-4/PEEP-4<br>* Spontaneous breathing of 100% oxygen in a facemask with application of an inspiratory pressure of 4 cm H2O and a positive end-expiratory pressure of 4 cm H2O, for 3 minutes<br>|
| Active Comparator: Standard preoxygenation (VS)<br> | Other: VS<br>* Spontaneous breathing of 100% oxygen in a facemask for 3 minutes<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| expiratory oxygen fraction (end-tidal 02) |  |  | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| inspiratory oxygen fraction |  |  | 
| end-tidal CO2 |  |  | 
| tidal volume |  |  | 
| inspiratory pressure |  |  | 
| subject's tolerance |  |  | 
| leaks around the mask during preoxygenation |  |  | 
| minute volume |  |  | 
| endexpiratory pressure |  |  | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Preoxygenation, Inspiratory, Support, Healthy, EndtidalO2