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

Accident Caused by Snow Avalanche Clinical Trial

— HyperAvaSM  

Official title:

Hypercapnia and Gas Exchange Under the Simulated Avalanche Snow

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02521272
• Other study ID #: VentRes-2015-01-KR
• Status: Completed
• Phase: N/A
• First received: August 10, 2015
• Last updated: August 11, 2015
• Start date: March 2012
• Est. completion date: March 2012

Study information

• Verified date: August 2015
• Source: Czech Technical University in Prague
• Contact: n/a
• Is FDA regulated: No
• Health authority: Czech Republic: State Institute for Drug Control
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 12
• Est. completion date: March 2012
• Est. primary completion date: March 2012
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Male
• Age group: 20 Years to 30 Years

Eligibility

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

Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Accident Caused by Snow Avalanche
• Hypercapnia

Intervention

Other:
• Breathing in the simulated avalanche snow.
Breathing in the simulated avalanche snow with zero air pocket and one-liter air pocket.

Device:
• air pocket
Zero air pocket or one-liter air pocket in the snow.

Locations

Country	Name	City	State
Czech Republic	Charles University, Czech Republic	Prague

Sponsors (2)

Lead Sponsor	Collaborator
Czech Technical University in Prague	Charles University, Czech Republic

Country where clinical trial is conducted

Czech Republic, 

References & Publications (3)

Bellani G, Patroniti N, Weismann D, Galbiati L, Curto F, Foti G, Pesenti A. Measurement of pressure-time product during spontaneous assisted breathing by rapid interrupter technique. Anesthesiology. 2007 Mar;106(3):484-90. — View Citation

Brugger H, Sumann G, Meister R, Adler-Kastner L, Mair P, Gunga HC, Schobersberger W, Falk M. Hypoxia and hypercapnia during respiration into an artificial air pocket in snow: implications for avalanche survival. Resuscitation. 2003 Jul;58(1):81-8. — View Citation

Grissom CK, Radwin MI, Harmston CH, Hirshberg EL, Crowley TJ. Respiration during snow burial using an artificial air pocket. JAMA. 2000 May 3;283(17):2266-71. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	The length of breathing	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.	Continuously within 30 minute interval from the beginning of the breathing experiment	No