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

Официальное название

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

Обзор

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.

Вмешательства

• Устройство 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.
• Устройство 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.

Первичные конечные точки

• Course of PtCO2 measured transcutaneously [Срок оценки: 45 minutes]

Вторичные конечные точки (9)

• Burial time until the test is terminated [Срок оценки: 45 minutes]
• Course of PetCO2 [Срок оценки: 45 minutes]
• Progression of respiratory minute volume [Срок оценки: 45 minutes]
• Course of the body temperature [Срок оценки: 45 minutes]
• Heart rate progression and variability [Срок оценки: 45 minutes]
• Course of PtO2 [Срок оценки: 45 minutes]
• Course of PetO2 [Срок оценки: 45 minutes]
• Course of SpO2 [Срок оценки: 45 minutes]
• Progression of Respiratory rate [Срок оценки: 45 minutes]

Критерии участия

Критерии включения

• Adults over 18
• Able to consent

Критерии исключения

• 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

Критерии приведены из реестра в оригинале (на английском). Окончательную оценку соответствия проводит исследовательский центр.

Здоровые добровольцы: Да

Дизайн исследования

Распределение

Рандомизированное

Модель

Перекрёстный дизайн

Маскирование

Двойное слепое

Основная цель

Фундаментальное исследование

Центры проведения

Швейцария · 1 центр

• Kantonsspital Aarau — Aarau

Публикации

• Schaerli F, Buse S, Farquharson F, Weiss B, Klenze H, Allen R, Walterspacher S, Gruber M, Schuetz P, Spengler CM, Kabitz HJ. Changes in systemic carbon dioxide levels during simulated avalanche burial using a one-way valve device: A randomized, double-blind, crossover trial. Respir Physiol Neurobiol. 2026 Jul;343:104588. doi: 10.1016/j.resp.2026.104588. Epub 2026 May 1. PMID 42070761

Идентификаторы

NCT: NCT06802744 · 2024-02335

Первоисточники (государственные реестры)

• ClinicalTrials.gov (NIH, США)

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