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Eisendle F, Rauch S, Wallner B, Brugger H, Strapazzon G. Prevalence of airway patency and air pocket in critically buried avalanche victims - a scoping review. Scand J Trauma Resusc Emerg Med 2024; 32:34. [PMID: 38654361 PMCID: PMC11040957 DOI: 10.1186/s13049-024-01205-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 04/09/2024] [Indexed: 04/25/2024] Open
Abstract
INTRODUCTION Survival of critically buried avalanche victims is directly dependent on the patency of the airway and the victims' ability to breathe. While guidelines and avalanche research have consistently emphasized on the importance of airway patency, there is a notable lack of evidence regarding its prevalence. OBJECTIVE The aim of this review is to provide insight into the prevalence of airway patency and air pocket in critically buried avalanche victims. METHODS A scoping review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline extension for scoping reviews. MEDLINE and Cochrane databases, as well as additional manual searching was performed to identify literature reporting data on airway patency and the presence of an air pocket in critically buried avalanche victims. After eliminating duplicates, we screened abstracts and main texts to identify eligible studies. RESULTS Of 4,109 studies identified 154 were eligible for further screening. Twenty-four publications and three additional data sources with a total number of 566 cases were included in this review. The proportion of short-term (< 35 min) to long-term burial (≥ 35 min) in the analysed studies was 19% and 66%, respectively. The burial duration remained unknown in 12% of cases. The prevalence of airway patency in critically buried avalanche victims was 41% while that of airway obstruction was 12%, with an overall rate of reporting as low as 50%. An air pocket was present in 19% of cases, absent in 46% and unknown in 35% of the cases. CONCLUSION The present study found that in critically buried avalanche victims patent airways were more than three times more prevalent than obstructed, with the airway status reported only in half of the cases. This high rate of airway patency supports the ongoing development and the effectiveness of avalanche rescue systems which oppose asphyxiation in critically buried avalanche victims. Further effort should be done to improve the documentation of airway patency and the presence of an air pocket in avalanche victims and to identify factors affecting the rate of airway obstruction.
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Affiliation(s)
- Frederik Eisendle
- Institute of Mountain Emergency Medicine, Eurac Research, Via Ipazia 2, Bolzano, 39100, Italy
- Department of Anaesthesiology and Intensive Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
| | - Simon Rauch
- Institute of Mountain Emergency Medicine, Eurac Research, Via Ipazia 2, Bolzano, 39100, Italy
- Department of Anaesthesia and Intensive Care Medicine, Hospital of Merano, Merano, Italy
| | - Bernd Wallner
- Department of Anaesthesiology and Intensive Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Via Ipazia 2, Bolzano, 39100, Italy
| | - Giacomo Strapazzon
- Institute of Mountain Emergency Medicine, Eurac Research, Via Ipazia 2, Bolzano, 39100, Italy.
- Department of Anaesthesiology and Intensive Care Medicine, Medical University of Innsbruck, Innsbruck, Austria.
- SIMeM Italian Society of Mountain Medicine, Padova, Italy.
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Van Tilburg C, Paal P, Strapazzon G, Grissom CK, Haegeli P, Hölzl N, McIntosh S, Radwin M, Smith WWR, Thomas S, Tremper B, Weber D, Wheeler AR, Zafren K, Brugger H. Wilderness Medical Society Clinical Practice Guidelines for Prevention and Management of Avalanche and Nonavalanche Snow Burial Accidents: 2024 Update. Wilderness Environ Med 2024; 35:20S-44S. [PMID: 37945433 DOI: 10.1016/j.wem.2023.05.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 04/03/2023] [Accepted: 05/10/2023] [Indexed: 11/12/2023]
Abstract
To provide guidance to the general public, clinicians, and avalanche professionals about best practices, the Wilderness Medical Society convened an expert panel to revise the evidence-based guidelines for the prevention, rescue, and resuscitation of avalanche and nonavalanche snow burial victims. The original panel authored the Wilderness Medical Society Practice Guidelines for Prevention and Management of Avalanche and Nonavalanche Snow Burial Accidents in 2017. A second panel was convened to update these guidelines and make recommendations based on quality of supporting evidence.
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Affiliation(s)
- Christopher Van Tilburg
- Occupational Medicine, Mountain Clinic, and Emergency Medicine, Providence Hood River Memorial Hospital, Hood River, OR
- Mountain Rescue Association, San Diego, CA
- International Commission for Alpine Rescue
| | - Peter Paal
- International Commission for Alpine Rescue
- Department of Anesthesiology and Critical Care Medicine, St. John of God Hospital, Paracelsus Medical University, Salzburg, Austria
| | - Giacomo Strapazzon
- International Commission for Alpine Rescue
- Department of Anesthesiology and Critical Care Medicine, University Hospital Innsbruck, Innsbruck, Austria
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Colin K Grissom
- Department of Pulmonary and Critical Care, Intermountain Medical Center, Murray, UT
| | | | - Natalie Hölzl
- International Commission for Alpine Rescue
- German Association of Mountain and Expedition Medicine, Munich, Germany
| | - Scott McIntosh
- International Commission for Alpine Rescue
- Division of Emergency Medicine, University of Utah Health, Salt Lake City, UT
| | | | - William Will R Smith
- Mountain Rescue Association, San Diego, CA
- International Commission for Alpine Rescue
- Division of Emergency Medicine, University of Utah Health, Salt Lake City, UT
- Department of Emergency Medicine, St. Johns Health, Jackson, WY
- University of Washington School of Medicine, Seattle, WA
| | - Stephanie Thomas
- Mountain Rescue Association, San Diego, CA
- International Commission for Alpine Rescue
| | | | - David Weber
- Intermountain Life Flight, Salt Lake City, UT
| | - Albert R Wheeler
- Mountain Rescue Association, San Diego, CA
- International Commission for Alpine Rescue
- Division of Emergency Medicine, University of Utah Health, Salt Lake City, UT
- Department of Emergency Medicine, St. Johns Health, Jackson, WY
| | - Ken Zafren
- International Commission for Alpine Rescue
- Himalayan Rescue Association, Kathmandu, Nepal
- Stanford University Medical Center, Palo Alto, CA
| | - Hermann Brugger
- International Commission for Alpine Rescue
- Department of Anesthesiology and Critical Care Medicine, University Hospital Innsbruck, Innsbruck, Austria
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
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Lugnet V, McDonough M, Gordon L, Galindez M, Mena Reyes N, Sheets A, Zafren K, Paal P. Termination of Cardiopulmonary Resuscitation in Mountain Rescue: A Scoping Review and ICAR MedCom 2023 Recommendations. High Alt Med Biol 2023; 24:274-286. [PMID: 37733297 DOI: 10.1089/ham.2023.0068] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/22/2023] Open
Abstract
Lugnet, Viktor, Miles McDonough, Les Gordon, Mercedes Galindez, Nicolas Mena Reyes, Alison Sheets, Ken Zafren, and Peter Paal. Termination of cardiopulmonary resuscitation in mountain rescue: a scoping review and ICAR MedCom 2023 recommendations. High Alt Med Biol. 24:274-286, 2023. Background: In 2012, the International Commission for Mountain Emergency Medicine (ICAR MedCom) published recommendations for termination of cardiopulmonary resuscitation (CPR) in mountain rescue. New developments have necessitated an update. This is the 2023 update for termination of CPR in mountain rescue. Methods: For this scoping review, we searched the PubMed and Cochrane libraries, updated the recommendations, and obtained consensus approval within the writing group and the ICAR MedCom. Results: We screened a total of 9,102 articles, of which 120 articles met the inclusion criteria. We developed 17 recommendations graded according to the strength of recommendation and level of evidence. Conclusions: Most of the recommendations from 2012 are still valid. We made minor changes regarding the safety of rescuers and responses to primary or traumatic cardiac arrest. The criteria for termination of CPR remain unchanged. The principal changes include updated recommendations for mechanical chest compression, point of care ultrasound (POCUS), extracorporeal life support (ECLS) for hypothermia, the effects of water temperature in drowning, and the use of burial times in avalanche rescue.
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Affiliation(s)
- Viktor Lugnet
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Department of Anesthesiology and Intensive Care, Östersund Hospital, Östersund, Sweden
- Swedish Mountain Guides Association (SBO), Gällivare, Sweden
| | - Miles McDonough
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Department of Emergency Medicine, UCSF Fresno, Fresno, California, USA
| | - Les Gordon
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Langdale Ambleside Mountain Rescue Team, Ambleside, United Kingdom
- Department of Anaesthesia, University Hospitals of Morecambe Bay Trust, Lancaster, United Kingdom
| | - Mercedes Galindez
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Department of Internal Medicine, Hospital Zonal Ramón Carrillo, San Carlos de Bariloche, Argentina
- Comisión de Auxilio Club Andino Bariloche, San Carlos de Bariloche, Argentina
| | - Nicolas Mena Reyes
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Department of Emergency Medicine, Sótero del Río Hospital, Santiago de Chile, Chile
- Grupo de Rescate Médico en Montaña (GREMM), Santiago, Chile
- Emegency Medicine Section, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alison Sheets
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Emergency Medicine, Boulder Community Health, Boulder, Colorado, USA
- Wilderness Medicine Section, University of Colorado Health Sciences Center, Aurora, Colorado, USA
| | - Ken Zafren
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Himalayan Rescue Association, Kathmandu, Nepal
- Department of Emergency Medicine, Stanford University Medical Center, Stanford, California, USA
- Alaska Native Medical Center, Anchorage, Alaska, USA
| | - Peter Paal
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Department of Anaesthesiology and Intensive Care Medicine, St. John of God Hospital, Paracelsus Medical University, Salzburg, Austria
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Strapazzon G, Rauch S, Malacrida S, Dal Cappello T, Governo E, Catuzzo B, Mrakic-Sposta S, Urgesi M, Falla M, Cavoretto G, Visetti E, Giardini G, Brugger H, Prato F. Comparative Effectiveness of an Artificial Air Pocket Device to Delay Asphyxiation in Supine Individuals Critically Buried in Avalanche Debris. JAMA Netw Open 2023; 6:e2313376. [PMID: 37184835 DOI: 10.1001/jamanetworkopen.2023.13376] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
Importance Approximately 70% of individuals critically buried in avalanche debris die within 35 minutes as a result of asphyxial cardiac arrest. An artificial air-pocket device (AAPD) that separates inhaled air from exhaled air may delay the onset of severe hypoxemia and eventual asphyxia during snow burial. Objective To investigate the efficacy of a new AAPD during snow burial in a supine position. Design, Setting, and Participants This comparative effectiveness trial was performed in winter 2016 with data analysis in November 2016 and November 2022. Each trial used a simulated critical avalanche burial scenario, in which a trough was dug in a snow pile and an additional air pocket of 0.5 L volume was punched into the lateral wall for each control trial. All participants were buried in a supine position. Trials could be voluntarily terminated at any time, with a maximum length of 60 minutes; trials were automatically terminated if the participant's peripheral oxygen saturation (Spo2) dropped to less than 84%. Exposures Each participant conducted 2 trials, one in which they breathed into the AAPD (intervention trial) and the other in which they breathed into the prepared air pocket (control trial). Main Outcomes and Measures Measurements included Spo2, cerebral oxygenation, ventilatory parameters, respiratory gas concentrations, and visual-analogue scales. Kaplan-Meier survival curves and rank test for matched survival data were used to analyze the total burial time in each trial. Results A total of 13 volunteers (9 men; mean [SD] age, 33 [8] years) were exposed to the intervention and control trials. Intervention trials were terminated less often (2 of 13 trials) as a result of hypoxemia than control trials (11 of 12 trials). Similarly, survival curves showed a longer duration of burial in the intervention compared with the control trials for the time to reach an Spo2 less than 84% (rank test for matched survival data: P = .003). The intervention trials, compared with the control trials, also had slower rates of decrease in fraction of inspired oxygen (mean [SD] rate, -0.8 [0.4] %/min vs -2.2 [1.2] %/min) and of increase in fraction of inspired carbon dioxide (mean [SD] rate, 0.5 [0.3] %/min vs 1.4 [0.6] %/min) and expired ventilation per minute (mean [SD] rate, 0.5 [1.0] L/min2 vs 3.9 [2.6] L/min2). Conclusions and Relevance This comparative effectiveness trial found that the new AAPD was associated with delaying the development of hypoxemia and hypercapnia in supine participants in a critical burial scenario. Use of the AAPD may allow a longer burial time before asphyxial cardiac arrest, which might allow longer times for successful rescue by companions or by prehospital emergency medical services.
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Affiliation(s)
- Giacomo Strapazzon
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
- Corpo Nazionale Soccorso Alpino e Speleologico, Milano, Italy
| | - Simon Rauch
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
- Department of Anesthesia and Intensive Care Medicine, F. Tappeiner Hospital, Merano, Italy
| | - Sandro Malacrida
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Tomas Dal Cappello
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Enrica Governo
- Mountain Medicine Center, Azienda Sanitaria Valle d'Aosta, Aosta, Italy
| | - Bruna Catuzzo
- Mountain Medicine Center, Azienda Sanitaria Valle d'Aosta, Aosta, Italy
| | | | - Margherita Urgesi
- Mountain Medicine Center, Azienda Sanitaria Valle d'Aosta, Aosta, Italy
| | - Marika Falla
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
- Center for Mind/Brain Sciences, University of Trento, Rovereto, Italy
| | | | - Enrico Visetti
- Mountain Medicine Center, Azienda Sanitaria Valle d'Aosta, Aosta, Italy
- Department of Anesthesia and Intensive Care, Gruppo Policlinico di Monza, Monza, Italy
| | - Guido Giardini
- Mountain Medicine Center, Azienda Sanitaria Valle d'Aosta, Aosta, Italy
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Federico Prato
- Corpo Nazionale Soccorso Alpino e Speleologico, Milano, Italy
- Mountain Medicine Center, Azienda Sanitaria Valle d'Aosta, Aosta, Italy
- Department of Emergency Medicine, Azienda Ospedaliero-Universitaria Maggiore della Carità, Novara, Italy
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Lechner R, Brugger H, Paal P, Hüfner K, Agazzi G, Butler F, Gordon L, Darocha T, Zafren K. Survival in a Collapsed Stable for 37 Days After Avalanche Burial in 1755. Wilderness Environ Med 2023; 34:113-119. [PMID: 36526516 DOI: 10.1016/j.wem.2022.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/20/2022] [Accepted: 10/26/2022] [Indexed: 12/15/2022]
Abstract
In 1755 in Bergemoletto, Italy, an avalanche buried 4 people (2 women, a girl, and a boy) and several animals in a stable. After 37 d in a pitch-dark confined space, 3 of the 4 people were rescued alive. The 3 survivors had only goat milk, a few chestnuts, a few kg of raw kid meat, and meltwater for nutrition. We describe the longest-known survival in an avalanche burial and discuss the medical and psychological problems of the survivors. The boy died. When they were extricated, all 3 survivors were exhausted, cachectic, and unable to stand or walk. They were severely malnourished and were experiencing tingling, tremors, and weakness in the legs; constipation; changes in taste; and amenorrhea. One of the women had persistent eye problems and developed symptoms consistent with post-traumatic stress disorder. The survivors were given slow refeeding. It took from 1 to 6 wk before they could walk. We compare this case to other long-duration burials, especially mining accidents, and describe the rescue and patient care after long-duration burials. This case demonstrates that people can overcome extremely adverse conditions and survive.
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Affiliation(s)
- Raimund Lechner
- Department of Anesthesiology, Intensive Care Medicine, Emergency Medicine, and Pain Therapy, Military Hospital, Ulm, Germany.
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; Department of Anesthesiology and Intensive Care Medicine, the Medical University of Innsbruck, Innsbruck, Austria; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland
| | - Peter Paal
- Department of Anaesthesiology and Intensive Care Medicine, St. John of God Hospital, Paracelsus Medical University, Salzburg, Austria
| | - Katharina Hüfner
- Department of Psychiatry, Psychotherapy, Psychosomatics and Medical Psychology, University Clinic for Psychiatry II (Psychosomatic Medicine), Innsbruck Medical University, Innsbruck, Austria
| | - Giancelso Agazzi
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland; Italian Society of Mountain Medicine, Padua, Italy; Italian Alpine Club Medical Commission, Milan, Italy
| | - Frank Butler
- US Department of Defense Joint Trauma System, San Antonio, TX; Departments of Military and Emergency Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD
| | - Les Gordon
- Department of Anaesthesia, University Hospitals of Morecambe Bay Trust, Lancaster, United Kingdom
| | - Tomasz Darocha
- Department of Anesthesiology and Intensive Care, Medical University of Silesia, Katowice, Poland
| | - Ken Zafren
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland; Department of Emergency Medicine, Alaska Native Medical Center, Anchorage, AK; Department of Emergency Medicine, Stanford University Medical Center, Stanford, CA
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Pasquier M, Strapazzon G, Kottmann A, Paal P, Zafren K, Oshiro K, Artoni C, Van Tilburg C, Sheets A, Ellerton J, McLaughlin K, Gordon L, Martin RW, Jacob M, Musi M, Blancher M, Jaques C, Brugger H. On-site treatment of avalanche victims: Scoping review and 2023 recommendations of the international commission for mountain emergency medicine (ICAR MedCom). Resuscitation 2023; 184:109708. [PMID: 36709825 DOI: 10.1016/j.resuscitation.2023.109708] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/17/2023] [Accepted: 01/18/2023] [Indexed: 01/27/2023]
Abstract
INTRODUCTION The International Commission for Mountain Emergency Medicine (ICAR MedCom) developed updated recommendations for the management of avalanche victims. METHODS ICAR MedCom created Population Intervention Comparator Outcome (PICO) questions and conducted a scoping review of the literature. We evaluated and graded the evidence using the American College of Chest Physicians system. RESULTS We included 120 studies including original data in the qualitative synthesis. There were 45 retrospective studies (38%), 44 case reports or case series (37%), and 18 prospective studies on volunteers (15%). The main cause of death from avalanche burial was asphyxia (range of all studies 65-100%). Trauma was the second most common cause of death (5-29%). Hypothermia accounted for few deaths (0-4%). CONCLUSIONS AND RECOMMENDATIONS For a victim with a burial time ≤ 60 minutes without signs of life, presume asphyxia and provide rescue breaths as soon as possible, regardless of airway patency. For a victim with a burial time > 60 minutes, no signs of life but a patent airway or airway with unknown patency, presume that a primary hypothermic CA has occurred and initiate cardiopulmonary resuscitation (CPR) unless temperature can be measured to rule out hypothermic cardiac arrest. For a victim buried > 60 minutes without signs of life and with an obstructed airway, if core temperature cannot be measured, rescuers can presume asphyxia-induced CA, and should not initiate CPR. If core temperature can be measured, for a victim without signs of life, with a patent airway, and with a core temperature < 30 °C attempt resuscitation, regardless of burial duration.
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Affiliation(s)
- M Pasquier
- Emergency Department, Lausanne University Hospital, Lausanne, Switzerland; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland.
| | - G Strapazzon
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; Medical University Innsbruck, Innsbruck, Austria; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zurich, Switzerland.
| | - A Kottmann
- Swiss Air Ambulance - Rega, Zurich Airport, Switzerland; Emergency Department, Lausanne University Hospital, Lausanne, Switzerland; Department of Anaesthesiology and Pain Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland.
| | - P Paal
- Department of Anaesthesiology and Intensive Care Medicine, St. John of God Hospital, Paracelsus Medical University Salzburg, Austria; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zurich, Switzerland
| | - K Zafren
- Department of Emergency Medicine, Alaska Native Medical Center Anchorage, Alaska, USA; Department of Emergency Medicine Stanford University Medical Center Stanford, CA, USA; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland
| | - K Oshiro
- Cardiovascular Department, Mountain Medicine, Research, & Survey Division, Hokkaido Ohno Memorial Hospital, Hokkaido, Japan; Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland
| | - C Artoni
- ICAR Avalanche Rescue Commission, Zürich, Switzerland.
| | - C Van Tilburg
- Providence Hood River Memorial Hospital, Hood River, Oregon, USA; Mountain Rescue Association, USA; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland.
| | - A Sheets
- Emergency Department, Boulder Community Health, Boulder, CO, USA; University of Colorado Wilderness and Environmental Medicine Fellowship Faculty, Aurora, CO, USA; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland.
| | - J Ellerton
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland
| | - K McLaughlin
- Canmore Hospital, Alberta, Canada; University of Calgary, Canada; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland.
| | - L Gordon
- Department of Anaesthesia, University Hospitals of Morecambe Bay Trust, Lancaster, England; Langdale Ambleside Mountain Rescue Team, England; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland
| | - R W Martin
- Mountain Rescue Association, USA; ICAR Avalanche Rescue Commission, Zürich, Switzerland.
| | - M Jacob
- Bavarian Mountain Rescue Service, Bad Tölz, Germany; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland.
| | - M Musi
- Emergency Department, University of Colorado, Aurora, Colorado, USA; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland.
| | - M Blancher
- Department of Emergency Medicine, University Hospital of Grenoble Alps Grenoble, France; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland.
| | - C Jaques
- Lausanne University Medical Library, Lausanne, Switzerland.
| | - H Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; Medical University Innsbruck, Innsbruck, Austria; International Commission for Mountain Emergency Medicine (ICAR MedCom), Zurich, Switzerland.
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Pulse Oximeter Performance during Rapid Desaturation. SENSORS 2022; 22:s22114236. [PMID: 35684858 PMCID: PMC9185462 DOI: 10.3390/s22114236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 05/26/2022] [Accepted: 05/30/2022] [Indexed: 02/04/2023]
Abstract
The reliability of pulse oximetry is crucial, especially in cases of rapid changes in body oxygenation. In order to evaluate the performance of pulse oximeters during rapidly developing short periods of concurrent hypoxemia and hypercapnia, 13 healthy volunteers underwent 3 breathing phases during outdoor experiments (39 phases in total), monitored simultaneously by five different pulse oximeters. A significant incongruity in values displayed by the tested pulse oximeters was observed, even when the accuracy declared by the manufacturers were considered. In 28.2% of breathing phases, the five used devices did not show any congruent values. The longest uninterrupted congruent period formed 74.4% of total recorded time. Moreover, the congruent periods were rarely observed during the critical desaturation phase of the experiment. The time difference between the moments when the first and the last pulse oximeter showed the typical study endpoint values of SpO2 85% and 75% was 32.1 ± 23.6 s and 24.7 ± 19.3 s, respectively. These results suggest that SpO2 might not be a reliable parameter as a study endpoint, or more importantly as a safety limit in outdoor experiments. In the design of future studies, more parameters and continuous clinical assessment should be included.
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Rauch S, Koppenberg J, Josi D, Meuli L, Strapazzon G, Pasquier M, Albrecht R, Brugger H, Zweifel B, Pietsch U. Avalanche survival depends on the time of day of the accident: A retrospective observational study. Resuscitation 2022; 174:47-52. [PMID: 35341911 DOI: 10.1016/j.resuscitation.2022.03.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/15/2022] [Accepted: 03/18/2022] [Indexed: 11/29/2022]
Abstract
INTRODUCTION We aimed to investigate the relationship between the time of the day and the probability of survival of completely buried avalanche victims. We explored the frequency of avalanche burials occurring after sunset, and described victims' characteristics, duration of burial and rescue circumstances compared to daytime avalanches. METHODS In this retrospective, observational study, we analysed avalanche data from the registry of the Swiss Institute for Snow and Avalanche Research, from 1998 to 2020. RESULTS A total of 3,892 avalanche victims were included in the analysis, with 72 of the accidents (1.85%) occurring in the nighttime. Nearly 50% of the victims involved in nighttime avalanche accidents were completely buried, compared to about 25% of victims in daytime avalanches. Completely buried victims were rescued by a companion less often at night than in the daytime (15% vs. 51%, p<.001). The search and rescue of completely buried avalanche victims took longer during the nighttime compared to the daytime (median 89 min vs 20 min, p=.002). The probability of survival decreased as the day progressed; it was highest at around midday (63.0%), but decreased at sunset (40.4%) and was the lowest at midnight (28.7%). CONCLUSIONS Avalanche accidents at night are a rare event, and probability of survival after complete burial is lower during the nighttime compared to the daytime. The most relevant reason for this is the longer duration of burial, which is explained in part by the lower rate of companion rescue and the lower rate of victim localisation with an avalanche transceiver.
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Affiliation(s)
- Simon Rauch
- Department of Anaesthesiology and Intensive Care Medicine, F. Tappeiner Hospital, Merano, Italy; Institute of Mountain Emergency Medicine, Eurac Research, Bozen, Italy.
| | - Joachim Koppenberg
- Department of Anaesthesiology, Pain Therapy and Emergency Medicine, Lower Engadine Hospital and Health Centre, Scuol, Switzerland; Aquatic Ecology, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland.
| | - Dario Josi
- Aquatic Ecology, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland; Department of Fish Ecology and Evolution, EAWAG Swiss Federal Institute of Aquatic Science and Technology, Center for Ecology, Evolution and Biogeochemistry, Kastanienbaum, Switzerland.
| | - Lorenz Meuli
- Department of Vascular Surgery, University Hospital Zurich, Zurich, Switzerland.
| | - Giacomo Strapazzon
- Institute of Mountain Emergency Medicine, Eurac Research, Bozen, Italy; Department of Anaesthesiology and Intensive Care Medicine, Innsbruck Medical University, Innsbruck, Austria.
| | - Mathieu Pasquier
- Emergency Department, Lausanne University Hospital, Lausanne, Switzerland.
| | - Roland Albrecht
- Swiss Air-Ambulance, Rega (Rettungsflugwacht/Guarde Aérienne), Zurich, Switzerland; Department of Anaesthesiology and Intensive Care Medicine, Cantonal Hospital St, Gallen, St. Gallen, Switzerland.
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Bozen, Italy; Department of Anaesthesiology and Intensive Care Medicine, Innsbruck Medical University, Innsbruck, Austria.
| | - Benjamin Zweifel
- WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland.
| | - Urs Pietsch
- Swiss Air-Ambulance, Rega (Rettungsflugwacht/Guarde Aérienne), Zurich, Switzerland; Department of Anaesthesiology and Intensive Care Medicine, Cantonal Hospital St, Gallen, St. Gallen, Switzerland; Department of Emergency Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
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9
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Perlite is a suitable model material for experiments investigating breathing in high density snow. Sci Rep 2022; 12:2070. [PMID: 35136116 PMCID: PMC8827056 DOI: 10.1038/s41598-022-06015-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 01/20/2022] [Indexed: 11/30/2022] Open
Abstract
Outdoor breathing trials with simulated avalanche snow are fundamental for the research of the gas exchange under avalanche snow, which supports the development of the international resuscitation guidelines. However, these studies have to face numerous problems, including unstable weather and variable snow properties. This pilot study examines a mineral material perlite as a potential snow model for studies of ventilation and gas exchange parameters. Thirteen male subjects underwent three breathing phases—into snow, wet perlite and dry perlite. The resulting trends of gas exchange parameters in all tested materials were similar and when there was a significant difference observed, the trends in the parameters for high density snow used in the study lay in between the trends in dry and wet perlite. These findings, together with its stability and accessibility year-round, make perlite a potential avalanche snow model material. Perlite seems suitable especially for simulation and preparation of breathing trials assessing gas exchange under avalanche snow, and potentially for testing of new avalanche safety equipment before their validation in real snow. The study was registered in ClinicalTrials.gov on January 22, 2018; the registration number is NCT03413878.
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10
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Woyke S, Brugger H, Ströhle M, Haller T, Gatterer H, Dal Cappello T, Strapazzon G. Effects of Carbon Dioxide and Temperature on the Oxygen-Hemoglobin Dissociation Curve of Human Blood: Implications for Avalanche Victims. Front Med (Lausanne) 2022; 8:808025. [PMID: 35198571 PMCID: PMC8859098 DOI: 10.3389/fmed.2021.808025] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 12/20/2021] [Indexed: 11/13/2022] Open
Abstract
Completely avalanche-buried patients are frequently exposed to a combination of hypoxia and hypercapnia with a risk of normothermic cardiac arrest. Patients with a long burial time and an air pocket are exposed to a combination of hypoxia, hypercapnia, and hypothermia which may lead to the development of the “triple H syndrome”. This specific combination has several pathophysiological implications, particularly on the cardiovascular system and oxygen transport (oxygen supply and oxygen consumption). To examine the effects on hemoglobin oxygen affinity, we investigated venous blood samples from 15 female and 15 male healthy subjects. In a factorial design of four different carbon dioxide partial pressure (PCO2) levels (20, 40, 60, and 80 mmHg) and five different temperature levels (13.7°C, 23°C, 30°C, 37°C, and 42°C), 30 unbuffered whole blood samples were analyzed in a newly developed in vitro method for high-throughput oxygen dissociation curve (ODC) measurements. P50s, Hill coefficients, CO2-Bohr coefficients, and temperature coefficients were analyzed using a linear mixed model (LMM). Mean P50 at baseline (37°C, 40 mmHg PCO2) was 27.1 ± 2.6 mmHg. Both CO2-Bohr (p < 0.001) and temperature coefficients (p < 0.001) had a significant effect on P50. The absolute CO2 effect was still pronounced at normothermic and febrile temperatures, whereas at low temperatures, the relative CO2 effect (expressed by CO2-Bohr coefficient; p < 0.001, interaction) was increased. The larger impact of PCO2 on oxygen affinity at low temperature may be caused by the competition of 2,3-BPG with PCO2 and the exothermic binding characteristic of 2,3-BPG. In a model of an avalanche burial, based on published data of CO2 levels and cooling rates, we calculated the resulting P50 for this specific condition based on the here-reported PCO2 and temperature effect on ODC. Depending on the degree of hypercapnia and hypothermia, a potentially beneficial increase in hemoglobin oxygen affinity in the hypoxic condition might ensue.
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Affiliation(s)
- Simon Woyke
- Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Hermann Brugger
- Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Mathias Ströhle
- Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
- *Correspondence: Mathias Ströhle
| | - Thomas Haller
- Institute of Physiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Hannes Gatterer
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Tomas Dal Cappello
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Giacomo Strapazzon
- Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
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11
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Prevention of Hypothermia in the Aftermath of Natural Disasters in Areas at Risk of Avalanches, Earthquakes, Tsunamis and Floods. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19031098. [PMID: 35162119 PMCID: PMC8834683 DOI: 10.3390/ijerph19031098] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/13/2022] [Accepted: 01/14/2022] [Indexed: 11/17/2022]
Abstract
Throughout history, accidental hypothermia has accompanied natural disasters in cold, temperate, and even subtropical regions. We conducted a non-systematic review of the causes and means of preventing accidental hypothermia after natural disasters caused by avalanches, earthquakes, tsunamis, and floods. Before a disaster occurs, preventive measures are required, such as accurate disaster risk analysis for given areas, hazard mapping and warning, protecting existing structures within hazard zones to the greatest extent possible, building structures outside hazard zones, and organising rapid and effective rescue. After the event, post hoc analyses of failures, and implementation of corrective actions will reduce the risk of accidental hypothermia in future disasters.
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12
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Wik L, Brattebø G, Østerås Ø, Assmus J, Irusta U, Aramendi E, Mydske S, Skaalhegg T, Christjar Skaiaa S, Thomassen Ø. Physiological effects of providing supplemental air for avalanche victims. A randomised trial. Resuscitation 2022; 172:38-46. [DOI: 10.1016/j.resuscitation.2022.01.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/23/2021] [Accepted: 01/11/2022] [Indexed: 11/28/2022]
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13
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On-Site Medical Management of Avalanche Victims-A Narrative Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph181910234. [PMID: 34639535 PMCID: PMC8507645 DOI: 10.3390/ijerph181910234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/18/2021] [Accepted: 09/19/2021] [Indexed: 12/26/2022]
Abstract
Avalanche accidents are common in mountain regions and approximately 100 fatalities are counted in Europe each year. The average mortality rate is about 25% and survival chances are mainly determined by the degree and duration of avalanche burial, the patency of the airway, the presence of an air pocket, snow characteristics, and the severity of traumatic injuries. The most common cause of death in completely buried avalanche victims is asphyxia followed by trauma. Hypothermia accounts for a minority of deaths; however, hypothermic cardiac arrest has a favorable prognosis and prolonged resuscitation and extracorporeal rewarming are indicated. In this article, we give an overview on the pathophysiology and on-site management of avalanche victims.
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14
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Strapazzon G, Schweizer J, Chiambretti I, Brodmann Maeder M, Brugger H, Zafren K. Effects of Climate Change on Avalanche Accidents and Survival. Front Physiol 2021; 12:639433. [PMID: 33912070 PMCID: PMC8072472 DOI: 10.3389/fphys.2021.639433] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/15/2021] [Indexed: 11/13/2022] Open
Abstract
Avalanches are major natural hazards in snow-covered mountains, threatening people and infrastructure. With ongoing climate change, the frequency and types of snow avalanches may change, affecting the rates of avalanche burial and survival. With a wetter and warmer snow climate, consequences of burial may become more severe. In this review, we assess the potential effects of climate change on the frequency and characteristics of avalanches. We then discuss how these changes might affect the survival rates of subjects buried by avalanches and might influence the responses of search and rescue (SAR) teams and health care providers. While climate change is inevitable, the effects on avalanches remain elusive. The frequency of human triggered avalanches may not change, because this depends largely on the number and behavior of winter recreationists. Blunt trauma and secondary injuries will likely become more frequent as terrain roughness is expected to rise and snow cover to become thinner. Higher snow densities in avalanche debris will likely interfere with the respiration of completely buried victims. Asphyxia and trauma, as causes of avalanche death, may increase. It is unlikely that SAR and health care providers involved in avalanche rescue will have to change their strategies in areas where they are already established. The effects of climate change might foster the expansion of mitigation strategies and the establishment of mountain rescue services in areas subject to increased avalanche hazards caused by changes in snow cover and land use.
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Affiliation(s)
- Giacomo Strapazzon
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy.,International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland
| | - Jürg Schweizer
- WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland
| | - Igor Chiambretti
- AINEVA Interregional Association for Coordination and Documentation of Snow and Avalanche Problems, Trento, Italy
| | - Monika Brodmann Maeder
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy.,Department of Emergency Medicine, Inselspital University Hospital Bern and Bern University, Bern, Switzerland
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy.,International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland
| | - Ken Zafren
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Zürich, Switzerland.,Department of Emergency Medicine, Alaska Native Medical Center, Anchorage, AK, United States.,Department of Emergency Medicine, Stanford University Medical Center, Stanford, CA, United States
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15
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Strapazzon G, Gatterer H, Falla M, Dal Cappello T, Malacrida S, Turner R, Schenk K, Paal P, Falk M, Schweizer J, Brugger H. Hypoxia and hypercapnia effects on cerebral oxygen saturation in avalanche burial: A pilot human experimental study. Resuscitation 2020; 158:175-182. [PMID: 33249253 DOI: 10.1016/j.resuscitation.2020.11.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 11/04/2020] [Accepted: 11/17/2020] [Indexed: 10/22/2022]
Abstract
BACKGROUND A sufficient supply of oxygen is crucial to avoid hypoxic cardiac arrest and brain damage within 30 min in completely-buried avalanche victims. Snow density influences levels of hypoxia and hypercapnia. The goal of this study was to investigate the effects of hypoxia and hypercapnia on cerebral oxygenation (ScO2) in humans breathing into an artificial air pocket. METHODS Each subject breathed into a closed system (air-tight face mask - plastic tube - snow air-pocket of 4 L) up to 30 min. Each subject performed three tests in different snow densities. ScO2 was measured by a near-infrared spectroscopy (NIRS) device. Measurements included peripheral oxygen saturation (SpO2), end-tidal carbon dioxide (ETCO2), air pocket gases and blood gases. Snow density was assessed via standard methods and micro-computed tomography. Based on predetermined criteria, tests were classified based on whether they were terminated before 30 min and the reason for termination. The categories were: completed tests (30 min), tests terminated before 30 min when SpO2 dropped to ≤75% and tests that were terminated before 30 min by requests of the subjects. General linear models were used to compare termination groups for changes in ScO2, ETCO2, SpO2 and air pocket gases, and a multivariate analysis was used to detect factor independent effects on ScO2. RESULTS ScO2 was decreased in the group in which the tests were terminated for SpO2 ≤ 75% caused by a decrease in oxygen supply in high snow densities. In the completed tests, an increase in ScO2 occurred despite decreased oxygen supply and decreased carbon dioxide removal. CONCLUSIONS Our data show that ScO2 determined by NIRS was not always impaired in humans breathing into an artificial air pocket despite decreased oxygen supply and decreased carbon dioxide removal. This may indicate that in medium to low snow densities brain oxygenation can be sufficient, which may reflect the initial stage of the triple H (hypothermia, hypoxia, and hypercapnia) syndrome. In high snow densities, ScO2 showed a significant decrease caused by a critical decrease in oxygen supply. This could lead to a higher risk of hypoxic cardiac arrest and brain damage.
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Affiliation(s)
- Giacomo Strapazzon
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; Department of Anaesthesiology and Intensive Care Medicine, Medical University Innsbruck, Innsbruck, Austria.
| | - Hannes Gatterer
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Marika Falla
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; Centre for Mind/Brain Sciences - CIMeC, University of Trento, Rovereto (TN), Italy
| | - Tomas Dal Cappello
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Sandro Malacrida
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Rachel Turner
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Kai Schenk
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Peter Paal
- Department of Anaesthesiology and Intensive Care Medicine, Hospitallers Brothers Hospital, Teaching Hospital of the Paracelsus Medical University, Salzburg, Austria
| | - Markus Falk
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Jürg Schweizer
- WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; Department of Anaesthesiology and Intensive Care Medicine, Medical University Innsbruck, Innsbruck, Austria
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16
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Strapazzon G, Putzer G, Dal Cappello T, Falla M, Braun P, Falk M, Glodny B, Pinggera D, Helbok R, Brugger H. Effects of hypothermia, hypoxia, and hypercapnia on brain oxygenation and hemodynamic parameters during simulated avalanche burial: a porcine study. J Appl Physiol (1985) 2020; 130:237-244. [PMID: 33151777 DOI: 10.1152/japplphysiol.00498.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Avalanche patients who are completely buried but still able to breathe are exposed to hypothermia, hypoxia, and hypercapnia (triple H syndrome). Little is known about how these pathological changes affect brain physiology. The study aim was to investigate the effect of hypothermia, hypoxia, and hypercapnia on brain oxygenation and systemic and cerebral hemodynamics. Anesthetized pigs were surface cooled to 28°C. Fraction of inspiratory oxygen ([Formula: see text]) was reduced to 17% and hypercapnia induced. Hemodynamic parameters and blood gas values were monitored. Cerebral measurements included cerebral perfusion pressure (CPP), brain tissue oxygen tension ([Formula: see text]), cerebral venous oxygen saturation ([Formula: see text]), and regional cerebral oxygen saturation (rSo2). Tests were interrupted when hemodynamic instability occurred or 60 min after hypercapnia induction. ANOVA for repeated measures was used to compare values across phases. There was no clinically relevant reduction in cerebral oxygenation ([Formula: see text], [Formula: see text], rSo2) during hypothermia and initial [Formula: see text] reduction. Hypercapnia was associated with an increase in pulmonary resistance followed by a decrease in cardiac output and CPP, resulting in hemodynamic instability and cerebral desaturation (decrease in [Formula: see text], [Formula: see text], rSo2). Hypercapnia may be the main cause of cardiovascular instability, which seems to be the major trigger for a decrease in cerebral oxygenation in triple H syndrome despite severe hypothermia.NEW & NOTEWORTHY Avalanche patients who are completely buried but still able to breathe are exposed to hypothermia, hypoxia, and hypercapnia (triple H syndrome). In a porcine model, there was no clinically relevant reduction in cerebral oxygenation during hypothermia and initial reduction of fraction of inspiratory oxygen ([Formula: see text]), as observed during hypercapnia. Hypercapnia may be the main cause of cardiovascular instability, which seems to be the major trigger for a decrease in cerebral oxygenation in triple H syndrome despite severe hypothermia.
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Affiliation(s)
- Giacomo Strapazzon
- Eurac Research, Institute of Mountain Emergency Medicine, Bolzano, Italy.,Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
| | - Gabriel Putzer
- Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
| | - Tomas Dal Cappello
- Eurac Research, Institute of Mountain Emergency Medicine, Bolzano, Italy
| | - Marika Falla
- Eurac Research, Institute of Mountain Emergency Medicine, Bolzano, Italy.,Centre for Mind/Brain Sciences (CIMeC), University of Trento, Italy
| | - Patrick Braun
- Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
| | - Markus Falk
- Eurac Research, Institute of Mountain Emergency Medicine, Bolzano, Italy
| | - Bernhard Glodny
- Department of Radiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Daniel Pinggera
- Department of Neurosurgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Raimund Helbok
- Neurological Intensive Care Unit, Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
| | - Hermann Brugger
- Eurac Research, Institute of Mountain Emergency Medicine, Bolzano, Italy.,Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
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17
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McIntosh SE, Little CE, Seibert TD, Polukoff NE, Grissom CK. Reply to: Reconsidering the air pocket around mouth and nose as a positive outcome predictor in completely buried avalanche victims. Resuscitation 2020; 152:210-211. [PMID: 32234369 DOI: 10.1016/j.resuscitation.2020.03.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 03/21/2020] [Indexed: 11/19/2022]
Affiliation(s)
- Scott E McIntosh
- University of Utah Health, Division of Emergency Medicine, 50 North Medical Drive, Salt Lake City, UT 84132, United States.
| | - Colin E Little
- University of Utah Health, Division of Emergency Medicine, 50 North Medical Drive, Salt Lake City, UT 84132, United States
| | - Thomas D Seibert
- University of Utah Health, Division of Emergency Medicine, 50 North Medical Drive, Salt Lake City, UT 84132, United States
| | - Natalya E Polukoff
- University of Utah Health, Division of Emergency Medicine, 50 North Medical Drive, Salt Lake City, UT 84132, United States
| | - Colin K Grissom
- Intermountain Medical Center, 5121 S Cottonwood St, Murray, UT 84107, United States
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18
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Strapazzon G, Brugger H, Paal P, Brown D. Reconsidering the air pocket around mouth and nose as a positive outcome predictor in completely buried avalanche victims. Resuscitation 2020; 152:208-209. [PMID: 32229217 DOI: 10.1016/j.resuscitation.2020.02.043] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 02/02/2020] [Indexed: 10/24/2022]
Affiliation(s)
- Giacomo Strapazzon
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; International Commission for Alpine Emergency Medicine (ICAR MEDCOM), Kloten, Switzerland.
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; International Commission for Alpine Emergency Medicine (ICAR MEDCOM), Kloten, Switzerland
| | - Peter Paal
- International Commission for Alpine Emergency Medicine (ICAR MEDCOM), Kloten, Switzerland; Department of Anaesthesiology and Intensive Care Medicine, St. John of God Hospital, Paracelsus Medical University, Salzburg, Austria
| | - Doug Brown
- International Commission for Alpine Emergency Medicine (ICAR MEDCOM), Kloten, Switzerland; Department of Emergency Medicine, Royal Columbian Hospital, University of British Columbia, Vancouver, Canada
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19
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Avalanche airbag post-burial active deflation - The ability to create an air pocket to delay asphyxiation and prolong survival. Resuscitation 2019; 146:155-160. [PMID: 31812665 DOI: 10.1016/j.resuscitation.2019.11.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 11/10/2019] [Accepted: 11/21/2019] [Indexed: 11/23/2022]
Abstract
AIM The primary purpose of an avalanche airbag is to prevent burial during an avalanche. Approximately twenty percent of avalanche victims deploying airbags become critically buried, however. One avalanche airbag actively deflates three minutes after deployment, potentially creating an air pocket. Our objective was to evaluate this air pocket and its potential to prevent asphyxiation. METHODS Twelve participants were fitted with an airbag and placed prone on the snow. Participants deployed the airbag and were buried in 1.5 m of snow for 60 min with vital signs including oxygen saturation (SpO2) and end-tidal CO2 (ETCO2) measured every minute. Participants completed a post-burial survey to determine head movement within the air pocket. RESULTS Eleven of the 12 participants (92%) completed 60 min of burial. Preburial baseline SpO2 measurements did not change significantly over burial time (P > 0.05). Preburial baseline ETCO2 measurements increased over the burial time (P < 0.02); only one ETCO2 value was outside of the normal ETCO2 range (35-45 mmHg). Participants reported they could move their head forward 11.2 cm (SD 4.8 cm) and backward 6.6 cm (SD 5.1 cm) with the majority of participants stated that they had enough head movement to separate the oral cavity from opposing snow if necessary. Visual examination during extrication revealed a well-defined air pocket in all burials. CONCLUSION The avalanche airbag under study creates an air pocket that appears to delay asphyxia, which could allow extra time for rescue and improve overall survival of avalanche victims.
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20
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Wallner B, Moroder L, Brandt A, Mair P, Erhart S, Bachler M, Putzer G, Turner R, Strapazzon G, Falk M, Brugger H. Extrication Times During Avalanche Companion Rescue: A Randomized Single-Blinded Manikin Study. High Alt Med Biol 2019; 20:245-250. [PMID: 31264903 DOI: 10.1089/ham.2019.0021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Aims: This study aimed to determine the time needed for one or two companion rescuers to access, extricate, and deliver cardiopulmonary resuscitation (CPR) to a fully buried manikin during a simulated avalanche burial scenario. Materials and Methods: In this randomized, single-blinded study, 18 medical students were required to extricate a manikin manually from a simulated avalanche burial of 1 m in depth, either alone or in teams of two. Each participant performed three consecutive tests with the manikin in three different positions in random order. Results: Median time to first manikin contact was 2.5 minutes, median time to airway access 7.2 minutes, and median time to standard position for CPR 10.1 minutes. Overall, the number of rescuers (one compared to two rescuers, 10.5 minutes vs. 9.3 minutes; p = 0.686) and the burial position of the manikin (10.8 minutes vs. 10.6 minutes vs. 8.8 minutes; p = 0.428) had no influence on extrication times. Preexisting training (6.1 minutes vs. 11.0 minutes p = 0.006) and a learning effect obtained during the experiments (12.4 minutes the first test vs. 9.3 in the third test; p = 0.017) improved all extrication times. Conclusion: It takes an average of 7 minutes after location of a simulated avalanche victim, buried at a depth of 1 m, to free the airway, plus a further 3 minutes to initiate CPR in standard supine position. This is more than two-thirds of the 15 minutes considered necessary for successful companion avalanche rescue. Even minimal training significantly reduced extrication times. These findings emphasize the importance of regular practice in specific extrication techniques that should be part of any training in avalanche companion rescue.
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Affiliation(s)
- Bernd Wallner
- Department of Anaesthesiology and Intensive Care Medicine, University Clinic Innsbruck, Medical University Innsbruck, Innsbruck, Austria.,Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Luca Moroder
- Department of Anaesthesiology and Critical Care Medicine, General Hospital Brixen, Brixen, Italy
| | - Anna Brandt
- Department of Anaesthesiology and Intensive Care Medicine, University Clinic Innsbruck, Medical University Innsbruck, Innsbruck, Austria
| | - Peter Mair
- Department of Anaesthesiology and Intensive Care Medicine, University Clinic Innsbruck, Medical University Innsbruck, Innsbruck, Austria
| | - Stefanie Erhart
- Department of Orthopaedics and Traumatology, University Hospital Hall in Tirol, Hall in Tirol, Austria
| | - Mirjam Bachler
- Department of Anaesthesiology and Intensive Care Medicine, University Clinic Innsbruck, Medical University Innsbruck, Innsbruck, Austria
| | - Gabriel Putzer
- Department of Anaesthesiology and Intensive Care Medicine, University Clinic Innsbruck, Medical University Innsbruck, Innsbruck, Austria
| | - Rachel Turner
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Giacomo Strapazzon
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Markus Falk
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
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21
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Strapazzon G, Brugger H. On-Site Treatment of Snow Avalanche Victims: From Bench to Mountainside. High Alt Med Biol 2018; 19:307-315. [PMID: 30183350 DOI: 10.1089/ham.2018.0036] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The number of avalanche accidents involving winter recreationists has notably increased in recent decades due to the increasing popularity of outdoor winter activities. The International Liaison Committee on Cardiopulmonary Resuscitation, the International Commission for Mountain Emergency Medicine (ICAR Medcom), and the Wilderness Medical Society have recently published evidenced-based recommendations for the on-site treatment of snow avalanche victims. Despite these recommendations, recent studies found poor knowledge and compliance by both healthcare providers and laypersons. The aim of this nonsystematic review is to provide an updated overview of avalanche accident epidemiology, to present recent advances in snow avalanche pathophysiology, and to discuss recent advancements in on-site treatment of snow avalanche victims.
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Affiliation(s)
- Giacomo Strapazzon
- 1 Institute of Mountain Emergency Medicine , Eurac Research, Bolzano, Italy .,2 International Commission of Mountain Emergency Medicine (ICAR Medcom) , Kloten, Switzerland
| | - Hermann Brugger
- 1 Institute of Mountain Emergency Medicine , Eurac Research, Bolzano, Italy .,2 International Commission of Mountain Emergency Medicine (ICAR Medcom) , Kloten, Switzerland
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