Clinical trial NCT03413878: Snow Properties and Its Modeling for Studying Gas Exchange Under the Simulated Avalanche Snow
Official title: Snow Properties and Its Modeling for Studying Gas Exchange Under the Simulated Avalanche Snow
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Accident Caused by Snow Avalanche
Keywords: snow
avalanche
hypercapnia
work of breathing
Lead sponsor: Czech Technical University in Prague
Sponsor class: OTHER
Collaborators: name: Charles University, Czech Republic
name: Ministry of Defence and Armed Forces of the Czech Republic
First posted: 2018-01-29
Enrollment: 45
Sex: ALL
Minimum age (years): 18
Maximum age (years): 50
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
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.

Eligibility criteria: 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

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: Kladno
country: Czechia
facility: Czech Technical University, Faculty of Biomedical Engineering
city: Prague
country: Czechia
facility: Charles University, Czech Republic
Study officials:
affiliation: Czech Technical University in Prague, FBMI
name: Karel Roubik, PhD
role: PRINCIPAL_INVESTIGATOR
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.
citation: Roubik K, Sieger L, Sykora K. Work of Breathing into Snow in the Presence versus Absence of an Artificial Air Pocket Affects Hypoxia and Hypercapnia of a Victim Covered with Avalanche Snow: A Randomized Double Blind Crossover Study. PLoS One. 2015 Dec 14;10(12):e0144332. doi: 10.1371/journal.pone.0144332. eCollection 2015.
citation: Strapazzon G, Paal P, Schweizer J, Falk M, Reuter B, Schenk K, Gatterer H, Grasegger K, Dal Cappello T, Malacrida S, Riess L, Brugger H. Effects of snow properties on humans breathing into an artificial air pocket - an experimental field study. Sci Rep. 2017 Dec 15;7(1):17675. doi: 10.1038/s41598-017-17960-4.
citation: Roubik K, Sykora K, Sieger L, Ort V, Horakova L, Walzel S. Perlite is a suitable model material for experiments investigating breathing in high density snow. Sci Rep. 2022 Feb 8;12(1):2070. doi: 10.1038/s41598-022-06015-y.