Snow Properties and Its Modeling for Studying Gas Exchange Under the Simulated Avalanche Snow

Study Overview
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Brief Summary
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The aim of the study is to investigate respiratory parameters of a person in the simulated avalanche snow and consequent use of the measured data for development of a mathematical-physical model of breathing during increasing hypercapnia in the avalanche.

Detailed Description
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The study is a part of a university research project aimed at studying physiological conditions and development of breathing parameters of a person breathing in the simulated avalanche snow. Presence of an air pocket and its size play an important role in survival of victims buried in the avalanche snow. Even small air pockets facilitate breathing, yet they do not provide a significant amount of fresh air for breathing. The investigators hypothesize that the size of the air pocket significantly affects the airflow resistance and work of breathing. The aim of the study is to investigate the effect of the air pocket volume on gas exchange and work of breathing in subjects breathing into the simulated avalanche snow.

Official Title
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Snow Properties and Its Modeling for Studying Gas Exchange Under the Simulated Avalanche Snow

Conditions
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Accident Caused by Snow Avalanche

Intervention / Treatment
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* Other: Breathing in the simulated avalanche snow


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy and fit volunteers, classified as The American Society of Anesthesiologists class I without a smoking history Exclusion Criteria: Tiffeneau Index less than 0.70 any cardiovascular or respiratory condition

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 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: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Wet snow/Small air pocket<br>Breathing in the simulated avalanche snow. Breathing into model of wet avalanche snow with a small air pocket | Other: Breathing in the simulated avalanche snow<br>* Breathing in the simulated wet or dry avalanche snow with a small or large air pocket<br>|
| Experimental: Dry snow/Small air pocket<br>Breathing in the simulated avalanche snow. Breathing into model of dry avalanche snow with a small air pocket | Other: Breathing in the simulated avalanche snow<br>* Breathing in the simulated wet or dry avalanche snow with a small or large air pocket<br>|
| Experimental: Wet snow/Large air pocket<br>Breathing in the simulated avalanche snow. Breathing into model of wet avalanche snow with a large air pocket | Other: Breathing in the simulated avalanche snow<br>* Breathing in the simulated wet or dry avalanche snow with a small or large air pocket<br>|
| Experimental: Dry snow/Large air pocket<br>Breathing in the simulated avalanche snow. Breathing into model of dry avalanche snow with a large air pocket | Other: Breathing in the simulated avalanche snow<br>* Breathing in the simulated wet or dry avalanche snow with a small or large air pocket<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The length of breathing | Time to termination of the breathing experiment due to the decision of the tested subject, or determined by high end-tidal carbon dioxide value or by the order by the clinician assessing the health status of the subjects. | Continuously within 30 minute interval from the beginning of the breathing experiment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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snow, avalanche, hypercapnia, work of breathing