Clinical trial NCT06802744: Changes in the Carbon Dioxide Content in the Body During a Simulated Avalanche Burial With and Without the Use of a Breathing Tube System.
Official title: Changes in Systemic Carbon Dioxide Levels During Simulated Avalanche Burial Using a One-way Valve Device: a Double Blinded, Randomized Cross-over Trial
Study type: INTERVENTIONAL
Overall status: ENROLLING_BY_INVITATION
Phase: NA
Conditions: Avalanche Burial
Keywords: AAPD
Artificial air-pocket device
Lead sponsor: Klinik fur Pneumologie und Schlafmedizin Kantonsspital Aarau
Sponsor class: INDUSTRY
First posted: 2025-01-31
Enrollment: 10
Sex: ALL
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: BASIC_SCIENCE

Brief summary: Every year, around 100 people die in avalanches in the Alps. Many of these accidents occur during winter sports. In most cases, the victims suffocate under the snow after the avalanche has come to a standstill. A key survival factor here is the time it takes to be rescued. If a buried victim is rescued within 15 minutes, the probability of survival is over 90%. After 35 minutes, however, this drops drastically to just 30%.

A modern avalanche rescue system, such as the AvaLung-device, could extend the survival time. The system directs the exhaled air via a tube to the back of the buried person so that no toxic CO2 concentrations build up in the available breathing cavity. It is also intended to prevent the formation of an "ice mask", which can impair the release of oxygen from the snow. This study investigates whether the AvaLung system can extend the survival time in the event of burial.

The aim is to test the effects of such a breathing tube system. The oxygen and carbon dioxide levels of the test subjects are measured while they are buried in a simulated avalanche - once with and once without the AvaLung system. In addition, it is investigated how long it takes before the buried subjects have to stop the examination, for example due to shortness of breath or deteriorating respiratory gases in the blood.

Test setup:

The test subjects lie on their backs with their heads and chests buried under snow. During the test phase, various parameters are continuously monitored, such as the breathing rate and the CO2 concentration in the blood. A comparative study is carried out: once with a functioning rescue system, and once with a manipulated (non-functioning) system.

Expected benefit:

The results of this study should contribute to a better understanding of the effectiveness of avalanche rescue systems and thus increase the chances of survival of avalanche victims in the future. This is particularly important today, as the number of winter sports enthusiasts and the number of avalanches triggered by them is constantly increasing.


Eligibility criteria: Inclusion Criteria:

* Adults over 18
* Able to consent

Exclusion Criteria:

* Anamnestic evidence of previous pulmonary or cardiac disease
* Known neuromuscular diseases
* Thoracic deformities
* Acute respiratory infections
* In women: Pregnancy (excluded by history and urine test)
* Age over 60 Years
* Presence of claustrophobia

Primary outcomes:
measure: Course of PtCO2 measured transcutaneously
timeFrame: 45 minutes
Secondary outcomes:
measure: Burial time until the test is terminated
timeFrame: 45 minutes
measure: Course of PetCO2
timeFrame: 45 minutes
measure: Progression of respiratory minute volume
timeFrame: 45 minutes
measure: Course of the body temperature
timeFrame: 45 minutes
measure: Heart rate progression and variability
timeFrame: 45 minutes
measure: Course of PtO2
timeFrame: 45 minutes
measure: Course of PetO2
timeFrame: 45 minutes
measure: Course of SpO2
timeFrame: 45 minutes
measure: Progression of Respiratory rate
timeFrame: 45 minutes
Other outcomes:
Locations:
city: Aarau
country: Switzerland
facility: Kantonsspital Aarau
state: Aargau
Study officials:
affiliation: Klinik für Pneumologie und Schlafmedizin Kantonsspital Aarau
name: Hans-Joachim Kabitz, Prof. Dr. med.
role: PRINCIPAL_INVESTIGATOR
References: