Clinical trial NCT02521272: Hypercapnia and Gas Exchange Under the Avalanche Snow Model (HyperAvaSM)
Official title: Hypercapnia and Gas Exchange Under the Simulated Avalanche Snow
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Accident Caused by Snow Avalanche
Lead sponsor: Czech Technical University in Prague
Sponsor class: OTHER
Collaborators: name: Charles University, Czech Republic
First posted: 2015-08-13
Enrollment: 12
Sex: MALE
Minimum age (years): 20
Maximum age (years): 30
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: BASIC_SCIENCE

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.

Eligibility criteria: 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.

Primary outcomes:
measure: The length of breathing
timeFrame: Continuously within 30 minute interval from the beginning of the breathing experiment
Secondary outcomes:
Other outcomes:
Locations:
city: Prague
country: Czech Republic
facility: Charles University, Czech Republic
Study officials:
affiliation: Czech Technical University in Prague
name: Karel Roubik, prof., Ph.D.
role: STUDY_DIRECTOR
References:
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. doi: 10.1016/s0300-9572(03)00113-8.
citation: 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. doi: 10.1097/00000542-200703000-00012.
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. doi: 10.1001/jama.283.17.2266.