Changes in the Carbon Dioxide Content in the Body During a Simulated Avalanche Burial With and Without the Use of a Breathing Tube System. (Avalanox)

Changes in Systemic Carbon Dioxide Levels During Simulated Avalanche Burial Using a One-way Valve Device: a Double Blinded, Randomized Cross-over Trial

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.

Study Overview

• Status: Enrolling by invitation
• Conditions: Avalanche Burial
• Intervention / Treatment: Device: Addition of an artificial air-pocket device during simulated avalanche burial; Device: Addition of a non-functioning artificial air-pocket device during simulated avalanche burial

• Study Type: Interventional
• Enrollment (Estimated): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Aargau
    • Aarau, Aargau, Switzerland, 5001
      • Kantonsspital Aarau

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Simulated avalanche burial using a artificial air-pocket device	Device: Addition of an artificial air-pocket device during simulated avalanche burial; In contrast to the control group, the subjects in this arm are provided with a functioning device that directs the exhaled air away from the area of the respiratory cavity.
Sham Comparator: Simulated avalanche burial using a non-functional artificial air-pocket device	Device: Addition of a non-functioning artificial air-pocket device during simulated avalanche burial; In contrast to the intervention arm, the subjects in this arm are provided with a non-functioning artificial air-pocket device which does not redirect the exhaled air away from the breathing-cavity.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Course of PtCO2 measured transcutaneously	45 minutes

Secondary Outcome Measures

Outcome Measure	Time Frame
Burial time until the test is terminated	45 minutes
Course of PetCO2	45 minutes
Progression of respiratory minute volume	45 minutes
Course of the body temperature	45 minutes
Heart rate progression and variability	45 minutes
Course of PtO2	45 minutes
Course of PetO2	45 minutes
Course of SpO2	45 minutes
Progression of Respiratory rate	45 minutes

Collaborators and Investigators

• Sponsor: Klinik fur Pneumologie und Schlafmedizin Kantonsspital Aarau
• Investigators: Principal Investigator: Hans-Joachim Kabitz, Prof. Dr. med., Klinik für Pneumologie und Schlafmedizin Kantonsspital Aarau

Study record dates

Study Major Dates

• Study Start (Estimated): February 7, 2025
• Primary Completion (Estimated): March 1, 2025
• Study Completion (Estimated): March 1, 2025

Study Registration Dates

• First Submitted: January 20, 2025
• First Submitted That Met QC Criteria: January 26, 2025
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: January 26, 2025
• Last Verified: January 1, 2025

More Information

Terms related to this study

• Keywords: AAPD; Artificial air-pocket device
• Other Study ID Numbers: 2024-02335

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No