Asphyxia; Immersion, Avalanche, Landslide, or Mudslide
Conditions
Keywords
Avalanche, Avalanche burial, Cardiac arrest, Asphyxia, Emergengy medicine
Brief summary
Survival of fully buried avalanche victims depends in major part on a triad of hypoxia, hypercapnia, and hypothermia and therefore decreases rapidly after complete burial. Besides optimizing companion rescue, which still today and even by trained people often takes more than 15 minutes to the extraction of an avalanche victim, prolonging the ability to breath after critical avalanche burial increases survival probability by giving rescuers more time to find and unbury avalanche victims. Based on previous research, the Norwegian company Safeback SE (Bergen, Norway) developed a new non-medical device using an innovative functional principle. The device, called the Safeback SBX (Safeback SE, Bergen, Norway), should make it possible to prevent asphyxia by delivering fresh air to the air pocket. Company claims to achieve a prolongation of survival up to over 60 minutes, giving companion rescuers as well as professional rescue teams more time to get access to the victim. Technical tests conducted by the developing company already provided some promising results regarding the general functioning. However, this study is needed to provide the scientific evidence of the effectiveness and influence on physiologic parameters buried in snow debris humans under realistic conditions.
Interventions
DEVICESafeback SBX
The intervention consists in the test of the active device.
DEVICESham device
The intervention consists in a similar device to that emits same noise but does not deliver airflow.
Sponsors
Medical University Innsbruck
Haukeland University Hospital
Institute of Mountain Emergency Medicine
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
\- healthy ASA I subjects
Exclusion criteria
* ASA class II or higher * chronic high degree cardiovascular or pulmonary disease * claustrophobia * psychiatric or neurological disease * long-term medication * pregnant woman * no informed consent * history of fever or serious cough in the past two weeks * current Covid-19 symptoms or recently tested positive for Covid-19 * body temperature ≥ 37.5°on test days.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Time limit | From baseline up to 60 minutes | Reaching a predefined time limit (min) |
| Physiological threshold | From baseline up to 60 minutes | Time to reach a SpO2 threshold up to \<75% (min) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Cerebral Regional Oxygen Saturation (rSO2) | Changes from baseline (measurement at 0 min) -> snow-breathing phase (5min, 15min, and timepoint immediately before interruption [up to 60 min) (countinuous monitoring) | Changes in rSO2 (%) |
| NASA-task load index (NASA-TLX) questionnaire (perceived workload) | Change from basal measurement (before hypoxia exposure) to post-exposure measurement (after hypoxia exposure - up to 60 min) | Changes in NASA-task load index (NASA-TLX) questionnaire (numerical scale) |
| End-tidal CO2 (EtCO2) | Changes from baseline (measurement at 0 min) -> snow-breathing phase (5min, 15min, and timepoint immediately before interruption [up to 60 min) (countinuous monitoring) | Changes in EtCO2 (mmHg) |
| Total antioxidant capacity - TAC | Change from basal measurement (before hypoxia exposure) to post-exposure measurement (after hypoxia exposure - up to 60 min) | Changes in TAC in saliva samples (mM) |
| Reactive oxygen species - ROS | Change from basal measurement (before hypoxia exposure) to post-exposure measurement (after hypoxia exposure - up to 60 min) | Changes in ROS in saliva samples (μmol/min) |
| Minute ventilation (VE) | Changes from baseline (measurement at 0 min) -> snow-breathing phase (5min, 15min, and timepoint immediately before interruption [up to 60 min) (countinuous monitoring) | Changes in VE (L/min) |
Countries
Italy
Contacts
Primary ContactFrederik Eisendle, Dr.
Outcome results
None listed