Hypercapnia and Gas Exchange Under the Avalanche Snow Model (HyperAvaSM)

Not Applicable

Completed

• Conditions: Accident Caused by Snow Avalanche
• Interventions: Other: Breathing in the simulated avalanche snow.; Device: air pocket

• Registration Number: NCT02521272
• Lead Sponsor: Czech Technical University in Prague

Brief Summary

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

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 and to test, whether it is possible to breathe with zero air pocket.

Study Timeline

• Study Start: 2012-03
• Primary Completion: 2012-03
• Study Completion: 2012-03
• Status Verified: 2015-08
• Study First Submitted: 2015-08-10
• Study First Submitted QC: 2015-08-11
• Last Update Submitted: 2015-08-11
• Study First Posted: 2015-08-13
• Last Update Posted: 2015-08-13

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 12

Inclusion Criteria

• Participants were volunteers from the Czech Army forces, studying at the Military Department of the Faculty of Physical Education and Sport, Charles University in Prague. All subjects were healthy and fit, classified as ASA I, all without a smoking history. The volunteers were highly motivated to participate in the experiment. The entrance examination, completed before the start of the study, included these tests: electrocardiography, blood pressure, spirometry, and assessment of the health conditions and family anamnesis by a physician with a specialty in anesthesia and critical care.

Exclusion Criteria

• The exclusion criteria were Tiffeneau Index less than 0.70 and any cardiovascular or respiratory condition.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
air pocket	air pocket	Breathing in the simulated avalanche snow.
air pocket	Breathing in the simulated avalanche snow.	Breathing in the simulated avalanche snow.

Primary Outcome Measures

Name	Time	Method
The length of breathing	Continuously within 30 minute interval from the beginning of the breathing experiment	Time to termination of the breathing experiment due to the decision of the subject, or determined by high End-Tidal CO2 value or by the order by the clinician assessing the health status of the subjects.

Trial Locations

Locations (1)

Charles University, Czech Republic; 🇨🇿 Prague, Czech Republic