Assessment of Preoxygenation Strategies in the Prehospital Environment

Study Overview
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Brief Summary
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Comparison of the preoxygenation efficacy of tidal volume breathing using three different preoxygenation techniques which are available to providers in the prehospital environment.

Detailed Description
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Prospective randomised interventional study. Healthy volunteers will be positioned supine and undergo preoxygenation by tidal volume breathing for 3 minutes using each technique in turn. The sequence of techniques for each volunteer will be randomised in advance. Investigators will be instructed to ensure a good mask seal throughout the testing period. At the end of a 3 minute preoxygenation period, after a brief breath hold, the volunteer will exhale into reservoir tubing, allowing the fractional expired oxygen concentration (FeO2) to be determined (primary outcome) using a calibrated gas analyser. The techniques being assessed have been chosen from methods of preoxygenation commonly available to clinicians in the prehospital environment: Continuous Positive Airway Pressure mode with fractional inspired oxygen concentration (FiO2) 100% using a portable ventilator. Bag-valve-mask device (BVM) with 15 l/min oxygen flow. Non-rebreather mask (NRM) device with 15 l/min oxygen flow. Volunteers will also be asked to indicate the subjective ease of breathing for each technique (secondary outcome) using a visual analogue scale (VAS).

Official Title
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Assessment of Preoxygenation Strategies in the Prehospital Environment

Conditions
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Anesthesia, Hypoxia

Intervention / Treatment
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* Device: Continuous Positive Airway Pressure (CPAP)
* Device: Bag-Valve-Mask (BVM)
* Device: Non-rebreather Mask (NRM)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult volunteers Exclusion Criteria: Pregnancy Respiratory disease Bearded Facial abnormality Edentulous

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: CPAP<br>3 minutes of preoxygenation with a portable ventilator providing Continuous Positive Airway Pressure (CPAP) at 5 cmH20 and an FiO2 of 100%. | Device: Continuous Positive Airway Pressure (CPAP)<br>* CPAP provided by a portable Draeger Oxylog® 3000 plus ventilator<br>|
| Experimental: BVM<br>3 minutes of preoxygenation with a bag-valve-mask (BVM) device and oxygen flow rate of 15 litres / minute. | Device: Bag-Valve-Mask (BVM)<br>* Preoxygenation provided by BVM device, oxygen flow rate 15 l/min<br>|
| Experimental: NRM<br>3 minutes of preoxygenation with a non-rebreather mask (NRM) device and oxygen flow rate of 15 litres / minute. | Device: Non-rebreather Mask (NRM)<br>* Preoxygenation provided by NRM, oxygen flow rate 15 l/min<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fractional Expired Oxygen Concentration | Measure of denitrogenation efficacy | 3 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ease of breathing assessment using a visual analogue scale | Visual analogue scale to assess subjective ease of breathing through each device | 3 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Oxygen Inhalation Therapy, Intubation, Emergency Medicine