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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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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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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: 5] [Impact Index Per Article: 5.0] [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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Sud S. Avalung: A saviour in avalanche. Med J Armed Forces India 2022; 78:S335-S336. [PMID: 36147393 PMCID: PMC9485737 DOI: 10.1016/j.mjafi.2020.04.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 04/23/2020] [Indexed: 11/18/2022] Open
Affiliation(s)
- Saurabh Sud
- Classified Specialist (Anaesthesia & Critical Care), 403 Field Hospital, C/O 56 APO, India
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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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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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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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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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Van Tilburg C. Should Airbag Backpacks Be Standard Avalanche Safety Equipment? Wilderness Environ Med 2021; 32:495-498. [PMID: 34366243 DOI: 10.1016/j.wem.2021.05.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 04/19/2021] [Accepted: 05/28/2021] [Indexed: 10/20/2022]
Abstract
Avalanche airbag backpacks have been shown to be effective at reducing avalanche mortality. However, they are yet to be considered standard avalanche safety equipment, which has long consisted of a transceiver, a shovel, and a probe. This is despite data showing that airbags reduce mortality by decreasing the likelihood of burial. In addition, airbags probably lessen trauma and possibly delay asphyxia. Moreover, the literature suggests airbags reduce mortality at a rate similar to transceivers. For those who work, volunteer, and recreate in avalanche terrain, airbags should be considered standard safety equipment. However, multiple barriers exist for universal adoption, including cost, size, weight, training burden, availability, risk tolerance, and lack of community support and recommendations from professional societies and associations.
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Affiliation(s)
- Christopher Van Tilburg
- Mountain Clinic, Occupational and Travel Medicine, and Emergency Department, Providence Hood River Memorial Hospital, Hood River, Oregon; Crag Rats Mountain Rescue, Portland Mountain Rescue, Clackamas County Search and Rescue, Pacific Northwest Search and Rescue, Hood River, Oregon.
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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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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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13
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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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14
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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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15
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Nichols TB, Hawley AC, Smith WR, Wheeler AR, McIntosh SE. Avalanche Safety Practices Among Backcountry Skiers and Snowboarders in Jackson Hole in 2016. Wilderness Environ Med 2018; 29:493-498. [PMID: 30213711 DOI: 10.1016/j.wem.2018.05.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 04/11/2018] [Accepted: 05/14/2018] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Carrying standard safety gear (beacon, probe, and shovel), planning a route of descent, and recreating with companions can help to mitigate the risk of injury or death resulting from avalanches in the backcountry. The goal of this study was to identify factors associated with performance of these safety practices. METHODS A convenience sample of backcountry skiers and snowboarders was surveyed in 2016 at the backcountry gates of Jackson Hole Mountain Resort. Each participant was surveyed on characteristics including skill level, sex, age, prior avalanche education, and residency in the Jackson Hole area. Safety practices were also measured against avalanche hazard forecasts. Correlations were assessed using Fisher's exact testing. RESULTS A total of 334 participants were surveyed. Factors associated with carrying avalanche safety gear included higher expertise, being a resident of the Jackson Hole area, and prior avalanche education. Factors associated with having a planned route of descent included higher expertise and being a resident of the Jackson Hole area. Factors associated with recreating with companions included younger age and lower expertise. Sex had no association with any of the surveyed safety practices. Participants were less likely to carry avalanche safety gear on low avalanche hazard days. CONCLUSIONS Certain individual characteristics of backcountry skiers and snowboarders are associated with increased frequency of adherence to recommended safety practices. These findings suggest that particular categories of backcountry recreationists may benefit from further avalanche safety education. The results of this study could help direct future educational efforts among backcountry recreationists.
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Affiliation(s)
- Ty B Nichols
- Department of Emergency Medicine, George Washington University Medical Center, Washington, DC and; Division of Emergency Medicine, TeamHealth, West Region, Emergency Professionals of Colorado, Greeley, CO (Dr Nichols)
| | - Alana C Hawley
- Division of Emergency Medicine, McMaster University, Hamilton General Hospital, Hamilton, Ontario (Dr Hawley); Division of Emergency Medicine, University of Utah, Salt Lake City, UT (Drs Hawley, Wheeler, and McIntosh)
| | - William R Smith
- St. John's Medical Center, Jackson, WY (Drs Wheeler and Smith); Division of Emergency Medicine, University of Washington School of Medicine, Seattle, WA (Dr Smith)
| | - Albert R Wheeler
- Division of Emergency Medicine, University of Utah, Salt Lake City, UT (Drs Hawley, Wheeler, and McIntosh); St. John's Medical Center, Jackson, WY (Drs Wheeler and Smith).
| | - Scott E McIntosh
- Division of Emergency Medicine, University of Utah, Salt Lake City, UT (Drs Hawley, Wheeler, and McIntosh)
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16
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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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17
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Effects of snow properties on humans breathing into an artificial air pocket - an experimental field study. Sci Rep 2017; 7:17675. [PMID: 29247235 PMCID: PMC5732296 DOI: 10.1038/s41598-017-17960-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 12/01/2017] [Indexed: 11/11/2022] Open
Abstract
Breathing under snow, e.g. while buried by a snow avalanche, is possible in the presence of an air pocket, but limited in time as hypoxia and hypercapnia rapidly develop. Snow properties influence levels of hypoxia and hypercapnia, but their effects on ventilation and oxygenation in humans are not fully elucidated yet. We report that in healthy subjects breathing into snow with an artificial air pocket, snow density had a direct influence on ventilation, oxygenation and exhaled CO2. We found that a rapid decline in O2 and increase in CO2 were mainly associated with higher snow densities and led to premature interruption due to critical hypoxia (SpO2 ≤ 75%). However, subjects in the low snow density group demonstrated a higher frequency of test interruptions than expected, due to clinical symptoms related to a rapid CO2 accumulation in the air pocket. Snow properties determine the oxygen support by diffusion from the surrounding snow and the clearance of CO2 by diffusion and absorption. Thus, snow properties are co-responsible for survival during avalanche burial.
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18
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Ruttmann E, Dietl M, Kastenberger T, El Attal R, Ströhle M, Ulmer H, Mair P. Characteristics and outcome of patients with hypothermic out-of-hospital cardiac arrest: Experience from a European trauma center. Resuscitation 2017; 120:57-62. [PMID: 28866108 DOI: 10.1016/j.resuscitation.2017.08.242] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 07/03/2017] [Accepted: 08/29/2017] [Indexed: 01/29/2023]
Abstract
BACKGROUND Aim of the study was to investigate patient characteristics, survival rates and neurological outcome among hypothermic patients with out-of-hospital cardiac arrest (OHCA) admitted to a trauma center. METHODS A review of patients with OHCA and a core temperature ≤32°C admitted to a trauma center between 2004 and 2016. RESULTS Ninety-six patients (mean temperature 25.8°C±3.9°C) were entered in the study, 37 (39%) of them after avalanche burial. 47% showed return of spontaneous circulation (ROSC) prior to hospital admission. Survival with Glasgow-Pittsburgh Cerebral Performance Category (CPC) scale 1 or 2 was achieved in 25% of all patients and was higher in non-avalanche than in avalanche cases (35.6% vs 8.1%, p=0.002). Witnessed cardiac arrest was the most powerful predictor of favourable neurological outcome (RR: 10.8; 95% Confidence Interval: 3.2-37.1; Wald: 14.3; p<0.001), whereas ROSC prior to admission and body core temperature were not associated with survival with favourable neurological outcome. Cerebral CT scan pathology within 12h of admission increased the risk for unfavourable neurological outcome 11.7 fold (RR: 11.7; 95% CI: 3.1-47.5; p<0.001). Favourable neurological outcome was associated lower S 100-binding protein (0.69±0.5μg/l vs 5.8±4.9μg/l, p 0.002) and neuron-specific enolase (34.7±14.2μg/l vs 88.4±42.7μg/l, p 0.004) concentrations on intensive care unit (ICU) admission. CONCLUSIONS Survival with favourable neurological outcome was found in about a third of all hypothermic non-avalanche patients with OHCA admitted to a trauma center.
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Affiliation(s)
- Elfriede Ruttmann
- Department of Cardiac Surgery, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Marion Dietl
- Department of Cardiac Surgery, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Tobias Kastenberger
- Department of Trauma Surgery, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Rene El Attal
- Department of Trauma Surgery, Academic Teaching Hospital Feldkirch, Carinnagasse 47, 6800 Feldkirch, Austria
| | - Mathias Ströhle
- Department of Anaesthesiology and Intensive Care Medicine, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Hanno Ulmer
- Department of Medical Statistics, Informatics, and Health Economy, Medical University of Innsbruck, Schoepfstrasse 41, 6020 Innsbruck, Austria
| | - Peter Mair
- Department of Anaesthesiology and Intensive Care Medicine, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
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19
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Van Tilburg C, Grissom CK, Zafren K, McIntosh S, Radwin MI, Paal P, Haegeli P, Smith WWR, Wheeler AR, Weber D, Tremper B, Brugger H. Wilderness Medical Society Practice Guidelines for Prevention and Management of Avalanche and Nonavalanche Snow Burial Accidents. Wilderness Environ Med 2017; 28:23-42. [PMID: 28257714 DOI: 10.1016/j.wem.2016.10.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 09/14/2016] [Accepted: 10/12/2016] [Indexed: 10/20/2022]
Abstract
To provide guidance to clinicians and avalanche professionals about best practices, the Wilderness Medical Society convened an expert panel to develop evidence-based guidelines for the prevention, rescue, and medical management of avalanche and nonavalanche snow burial victims. Recommendations are graded on the basis of quality of supporting evidence according to the classification scheme of the American College of Chest Physicians.
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Affiliation(s)
- Christopher Van Tilburg
- Occupational, Travel, and Emergency Medicine Departments, Providence Hood River Memorial Hospital, Hood River, OR (Dr Van Tilburg); Mountain Rescue Association, San Diego, CA (Drs Van Tilburg, Zafren, Smith, and Wheeler).
| | - Colin K Grissom
- Division of Pulmonary and Critical Care Medicine, Intermountain Medical Center and the University of Utah, Salt Lake City, UT (Dr Grissom)
| | - Ken Zafren
- Mountain Rescue Association, San Diego, CA (Drs Van Tilburg, Zafren, Smith, and Wheeler); Department of Emergency Medicine, Stanford University School of Medicine, Stanford, CA (Dr Zafren); International Commission for Mountain Emergency Medicine (Drs Brugger, Paal, and Zafren)
| | - Scott McIntosh
- Division of Emergency Medicine, University of Utah, Salt Lake City, UT (Drs McIntosh and Wheeler)
| | - Martin I Radwin
- Iasis Healthcare Physician Group of Utah, Salt Lake City, UT (Dr Radwin)
| | - Peter Paal
- International Commission for Mountain Emergency Medicine (Drs Brugger, Paal, and Zafren); Barts Heart Centre, St Bartholomew's Hospital, Barts Health NHS Trust, Queen Mary University of London, London, United Kingdom (Dr Paal); Department of Anesthesiology and Critical Care Medicine, University Hospital, Innsbruck, Austria (Dr Paal)
| | - Pascal Haegeli
- School of Resource and Environmental Management, Simon Fraser University, Burnaby, BC (Dr Haegeli)
| | - William Will R Smith
- Mountain Rescue Association, San Diego, CA (Drs Van Tilburg, Zafren, Smith, and Wheeler); Department of Emergency Medicine, St. Johns Medical Center, Jackson, WY (Drs Smith and Wheeler); Clinical WWAMI Faculty, University of Washington School of Medicine, Seattle, WA (Dr Smith)
| | - Albert R Wheeler
- Mountain Rescue Association, San Diego, CA (Drs Van Tilburg, Zafren, Smith, and Wheeler); Division of Emergency Medicine, University of Utah, Salt Lake City, UT (Drs McIntosh and Wheeler); Department of Emergency Medicine, St. Johns Medical Center, Jackson, WY (Drs Smith and Wheeler)
| | - David Weber
- Denali National Park & Preserve, Talkeetna, AK (Mr Weber); Intermountain Life Flight, Salt Lake City, UT (Mr Weber)
| | - Bruce Tremper
- Utah Avalanche Center, Salt Lake City, UT (Mr Tremper)
| | - Hermann Brugger
- International Commission for Mountain Emergency Medicine (Drs Brugger, Paal, and Zafren); EURAC Institute of Mountain Emergency Medicine, Bolzano, Italy (Dr Brugger)
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20
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Grasegger K, Strapazzon G, Procter E, Brugger H, Soteras I. Avalanche Survival After Rescue With the RECCO Rescue System: A Case Report. Wilderness Environ Med 2016; 27:282-6. [DOI: 10.1016/j.wem.2016.02.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 02/09/2016] [Accepted: 02/11/2016] [Indexed: 10/21/2022]
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21
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Work of Breathing into Snow in the Presence versus Absence of an Artificial Air Pocket Affects Hypoxia and Hypercapnia of a Victim Covered with Avalanche Snow: A Randomized Double Blind Crossover Study. PLoS One 2015; 10:e0144332. [PMID: 26666523 PMCID: PMC4682855 DOI: 10.1371/journal.pone.0144332] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 11/17/2015] [Indexed: 11/19/2022] Open
Abstract
Presence of an air pocket and its size play an important role in survival of victims buried in the avalanche snow. Even small air pockets facilitate breathing. We hypothesize that the size of the air pocket significantly affects the airflow resistance and work of breathing. The aims of the study are (1) to investigate the effect of the presence of an air pocket on gas exchange and work of breathing in subjects breathing into the simulated avalanche snow and (2) to test whether it is possible to breathe with no air pocket. The prospective interventional double-blinded study involved 12 male volunteers, from which 10 completed the whole protocol. Each volunteer underwent two phases of the experiment in a random order: phase “AP”—breathing into the snow with a one-liter air pocket, and phase “NP”—breathing into the snow with no air pocket. Physiological parameters, fractions of oxygen and carbon dioxide in the airways and work of breathing expressed as pressure-time product were recorded continuously. The main finding of the study is that it is possible to breath in the avalanche snow even with no air pocket (0 L volume), but breathing under this condition is associated with significantly increased work of breathing. The significant differences were initially observed for end-tidal values of the respiratory gases (EtO2 and EtCO2) and peripheral oxygen saturation (SpO2) between AP and NP phases, whereas significant differences in inspiratory fractions occurred much later (for FIO2) or never (for FICO2). The limiting factor in no air pocket conditions is excessive increase in work of breathing that induces increase in metabolism accompanied by higher oxygen consumption and carbon dioxide production. The presence of even a small air pocket reduces significantly the work of breathing.
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22
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Ng P, Smith WR, Wheeler A, McIntosh SE. Advanced Avalanche Safety Equipment of Backcountry Users: Current Trends and Perceptions. Wilderness Environ Med 2015; 26:417-21. [DOI: 10.1016/j.wem.2015.03.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 02/02/2015] [Accepted: 03/20/2015] [Indexed: 10/23/2022]
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23
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Kornhall DK, Martens-Nielsen J. The prehospital management of avalanche victims. J ROY ARMY MED CORPS 2015; 162:406-412. [PMID: 26092971 DOI: 10.1136/jramc-2015-000441] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 05/31/2015] [Accepted: 06/01/2015] [Indexed: 12/26/2022]
Abstract
Avalanche accidents are frequently lethal events with an overall mortality of 23%. Mortality increases dramatically to 50% in instances of complete burial. With modern day dense networks of ambulance services and rescue helicopters, health workers often become involved during the early stages of avalanche rescue. Historically, some of the most devastating avalanche accidents have involved military personnel. Armed forces are frequently deployed to mountain regions in order to train for mountain warfare or as part of ongoing conflicts. Furthermore, military units are frequently called to assist civilian organised rescue in avalanche rescue operations. It is therefore important that clinicians associated with units operating in mountain regions have an understanding of, the medical management of avalanche victims, and of the preceding rescue phase. The ensuing review of the available literature aims to describe the pathophysiology particular to avalanche victims and to outline a structured approach to the search, rescue and prehospital medical management.
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Affiliation(s)
- Daniel K Kornhall
- Anesthesia and Critical Care Research Group, UIT-The Arctic University of Norway, Tromsø, Norway.,Department of Internal Medicine, Helgeland Hospital Trust, Sandnessjoen, Norway.,East Anglian Air Ambulance, Marshall Airfield, Cambridge, UK.,Department of Anaesthesiology, University Hospital of North Norway, Tromsoe, Norway.,Svolvaer Alpine Rescue Group, Svolvaer, Norway
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Moroder L, Mair B, Brugger H, Voelckel W, Mair P. Outcome of avalanche victims with out-of-hospital cardiac arrest. Resuscitation 2015; 89:114-8. [PMID: 25625778 DOI: 10.1016/j.resuscitation.2015.01.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 01/13/2015] [Accepted: 01/16/2015] [Indexed: 10/24/2022]
Abstract
STUDY BACKGROUND Previous studies focused on the outcome of avalanche victims with out-of-hospital cardiac arrest (OHCA) after long duration of burial (>35min); the outcome of victims with short duration (≤35min) remains obscure. AIM OF THE STUDY To investigate outcome of avalanche victims with OHCA. METHODS Retrospective analysis of avalanche victims with OHCA between 2008 and 2013 in the Tyrolean Alps. RESULTS 55 avalanche victims were identified, 32 of whom were declared dead after extrication without cardiopulmonary resuscitation (CPR), all with long duration of burial. In the remaining 23 CPR was initiated at scene; three were partially and 20 completely buried, nine of whom suffered short and 11 long duration of burial. All nine victims with short duration of burial underwent restoration of spontaneous circulation (ROSC) at scene, four of them after bystander CPR, five after advanced life support by the emergency physician. Two patients with ROSC after short duration of burial and bystander CPR survived to hospital discharge with cerebral performance category 1. None of the 11 victims with long duration of burial survived to hospital discharge, although six were transported to hospital with ongoing CPR and three were supported with extracorporeal circulation. CONCLUSIONS In this case series survival with favourable neurological outcome was observed in avalanche victims with short duration of burial only if bystander CPR was immediately performed and ROSC achieved. Strategies for reducing avalanche mortality should focus on prompt extrication from the snow and immediate bystander CPR by uninjured companions.
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Affiliation(s)
- Luca Moroder
- Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Birgit Mair
- Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; Christophorus Emergency Medical Helicopter Service, Schubertring 1-3, 1010 Vienna, Austria
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, EURAC Research, Viale Druso 1, 39100 Bolzano, Italy
| | - Wolfgang Voelckel
- Christophorus Emergency Medical Helicopter Service, Schubertring 1-3, 1010 Vienna, Austria; Department of Anesthesiology and Critical Care Medicine, AUVA Trauma Hospital Salzburg, Dr.-Franz-Rehrl-Platz 4, 5010 Salzburg, Austria
| | - Peter Mair
- Department of Anaesthesiology and Critical Care Medicine, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; Christophorus Emergency Medical Helicopter Service, Schubertring 1-3, 1010 Vienna, Austria.
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25
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McIntosh SE, Crouch AK, Dorais A, McDevitt M, Wilson C, Harmston CH, Radwin MI, Grissom CK. Effect of head and face insulation on cooling rate during snow burial. Wilderness Environ Med 2014; 26:21-8. [PMID: 25281588 DOI: 10.1016/j.wem.2014.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 06/19/2014] [Accepted: 07/08/2014] [Indexed: 11/18/2022]
Abstract
OBJECTIVES Avalanche victims are subjected to a number of physiological stressors during burial. We simulated avalanche burial to monitor physiological data and determine whether wearing head and face insulation slows cooling rate during snow burial. In addition, we sought to compare 3 different types of temperature measurement methods. METHODS Nine subjects underwent 2 burials each, 1 with head and face insulation and 1 without. Burials consisted of a 60-minute burial phase followed by a 60-minute rewarming phase. Temperature was measured via 3 methods: esophageal probe, ingestible capsule, and rectal probe. RESULTS Cooling and rewarming rates were not statistically different between the 2 testing conditions when measured by the 3 measurement methods. All temperature measurement methods correlated significantly. CONCLUSIONS Head and face insulation did not protect the simulated avalanche victim from faster cooling or rewarming. Because the 3 temperature measurement methods correlated, the ingestible capsule may provide an advantageous noninvasive method for snow burial and future hypothermia studies if interruptions in data transmission can be minimized.
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Affiliation(s)
- Scott E McIntosh
- Division of Emergency Medicine, University of Utah Health Care, Salt Lake City, UT (Drs McIntosh and McDevitt).
| | - Andre K Crouch
- Department of Emergency Medicine, Intermountian Medical Center, Murray, UT (Drs Crouch and Dorais)
| | - Andrew Dorais
- Department of Emergency Medicine, Intermountian Medical Center, Murray, UT (Drs Crouch and Dorais)
| | - Marion McDevitt
- Division of Emergency Medicine, University of Utah Health Care, Salt Lake City, UT (Drs McIntosh and McDevitt)
| | - Courtney Wilson
- Department of Emergency Medicine, Rogue Regional Medical Center, Medford, OR (Dr Wilson)
| | | | | | - Colin K Grissom
- Shock Trauma ICU, Intermountain Medical Center, and Department of Medicine, University of Utah, Murray, UT (Dr Grissom)
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Boué Y, Payen JF, Brun J, Thomas S, Levrat A, Blancher M, Debaty G, Bouzat P. Survival after avalanche-induced cardiac arrest. Resuscitation 2014; 85:1192-6. [PMID: 24971508 DOI: 10.1016/j.resuscitation.2014.06.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 06/04/2014] [Accepted: 06/06/2014] [Indexed: 10/25/2022]
Abstract
AIM Criteria to prolong resuscitation after cardiac arrest (CA) induced by complete avalanche burial are critical since profound hypothermia could be involved. We sought parameters associated with survival in a cohort of victims of complete avalanche burial. METHODS Retrospective observational study of patients suffering CA on-scene after avalanche burial in the Northern French Alps between 1994 and 2013. Criteria associated with survival at discharge from the intensive care unit (ICU) were collected on scene and upon admission to Level-1 trauma center. Neurological outcome was assessed at 3 months using cerebral performance category score. RESULTS Forty-eight patients were studied. They were buried for a median time of 43 min (25-76 min; 25-75th percentiles) and had a pre-hospital body core temperature of 28.0°C (26.0-30.7). Eighteen patients (37.5%) had pre-hospital return of spontaneous circulation and 30 had refractory CA. Rewarming of 21 patients (43.7%) was performed using extracorporeal life support. Eight patients (16.7%) survived and were discharged from the ICU, three (6.3%) had favorable neurological outcome at 3 months. Pre-hospital parameters associated with survival were the presence of an air pocket and rescue collapse. On admission, survivors had lower serum potassium concentrations than non-survivors: 3.2 mmol/L (2.7-4.0) versus 5.6 mmol/L (4.2-8.0), respectively (P<0.01). They also had normal values for prothrombin and activated partial thromboplastin compared to non-survivors. CONCLUSIONS Our findings indicate that survival after avalanche burial and on-scene CA is rarely associated with favorable neurological outcome. Among criteria associated with survival, normal blood coagulation on admission warrants further investigation.
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Affiliation(s)
- Yvonnick Boué
- Pole Anesthésie-Réanimation, Hôpital Michallon, Grenoble F-38043, France; Université Joseph Fourier, Grenoble Institut des Neurosciences, Grenoble F-38043, France; INSERM, U836, Grenoble F-38042, France
| | - Jean-François Payen
- Pole Anesthésie-Réanimation, Hôpital Michallon, Grenoble F-38043, France; Université Joseph Fourier, Grenoble Institut des Neurosciences, Grenoble F-38043, France; INSERM, U836, Grenoble F-38042, France
| | - Julien Brun
- Pole Anesthésie-Réanimation, Hôpital Michallon, Grenoble F-38043, France
| | - Sébastien Thomas
- Pole Anesthésie-Réanimation, Hôpital Michallon, Grenoble F-38043, France
| | - Albrice Levrat
- Service réanimation, Centre Hospitalier Région d'Annecy, Metz-Tessy, F-74370, France
| | - Marc Blancher
- Service Urgences-SAMU-SMUR, Hopital Michallon, Grenoble F-38043, France
| | - Guillaume Debaty
- Service Urgences-SAMU-SMUR, Hopital Michallon, Grenoble F-38043, France
| | - Pierre Bouzat
- Pole Anesthésie-Réanimation, Hôpital Michallon, Grenoble F-38043, France; Université Joseph Fourier, Grenoble Institut des Neurosciences, Grenoble F-38043, France; INSERM, U836, Grenoble F-38042, France.
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Abstract
BACKGROUND Human activity in wilderness areas has increased globally in recent decades, leading to increased risk of injury and illness. Wilderness medicine has developed in response to both need and interest. METHODS The field of wilderness medicine encompasses many areas of interest. Some focus on special circumstances (such as avalanches) while others have a broader scope (such as trauma care). Several core areas of key interest within wilderness medicine are discussed in this study. RESULTS Wilderness medicine is characterized by remote and improvised care of patients with routine or exotic illnesses or trauma, limited resources and manpower, and delayed evacuation to definitive care. Wilderness medicine is developing rapidly and draws from the breadth of medical and surgical subspecialties as well as the technical fields of mountaineering, climbing, and diving. Research, epidemiology, and evidence-based guidelines are evolving. A hallmark of this field is injury prevention and risk mitigation. The range of topics encompasses high-altitude cerebral edema, decompression sickness, snake envenomation, lightning injury, extremity trauma, and gastroenteritis. Several professional societies, academic fellowships, and training organizations offer education and resources for laypeople and health care professionals. CONCLUSIONS THE FUTURE OF WILDERNESS MEDICINE IS UNFOLDING ON MULTIPLE FRONTS: education, research, training, technology, communications, and environment. Although wilderness medicine research is technically difficult to perform, it is essential to deepening our understanding of the contribution of specific techniques in achieving improvements in clinical outcomes.
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Affiliation(s)
- Douglas G. Sward
- Department of Emergency Medicine, University of Maryland School of Medicine, Hyperbaric Medicine, Shock Trauma Center, Baltimore, Maryland, USA
| | - Brad L. Bennett
- Military & Emergency Medicine Department, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
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Procter E, Strapazzon G, Dal Cappello T, Castlunger L, Staffler HP, Brugger H. Adherence of backcountry winter recreationists to avalanche prevention and safety practices in northern Italy. Scand J Med Sci Sports 2013; 24:823-9. [DOI: 10.1111/sms.12094] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2013] [Indexed: 11/29/2022]
Affiliation(s)
- E. Procter
- Institute of Mountain Emergency Medicine; EURAC research; Bolzano Italy
| | - G. Strapazzon
- Institute of Mountain Emergency Medicine; EURAC research; Bolzano Italy
- International Commission for Mountain Emergency Medicine ICAR MEDCOM; Bolzano Italy
| | - T. Dal Cappello
- Institute of Mountain Emergency Medicine; EURAC research; Bolzano Italy
| | - L. Castlunger
- Institute of Statistics; Autonomous Province of Bolzano; Bolzano Italy
| | - H. P. Staffler
- Department of Fire and Civil Protection; Autonomous Province of Bolzano; Bolzano Italy
| | - H. Brugger
- Institute of Mountain Emergency Medicine; EURAC research; Bolzano Italy
- International Commission for Mountain Emergency Medicine ICAR MEDCOM; Bolzano Italy
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Resuscitation of avalanche victims: Evidence-based guidelines of the international commission for mountain emergency medicine (ICAR MEDCOM): intended for physicians and other advanced life support personnel. Resuscitation 2012; 84:539-46. [PMID: 23123559 DOI: 10.1016/j.resuscitation.2012.10.020] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2012] [Revised: 10/14/2012] [Accepted: 10/23/2012] [Indexed: 11/22/2022]
Abstract
BACKGROUND In North America and Europe ∼150 persons are killed by avalanches every year. METHODS The International Commission for Mountain Emergency Medicine (ICAR MEDCOM) systematically developed evidence-based guidelines and an algorithm for the management of avalanche victims using a worksheet of 27 Population Intervention Comparator Outcome questions. Classification of recommendations and level of evidence are ranked using the American Heart Association system. RESULTS AND CONCLUSIONS If lethal injuries are excluded and the body is not frozen, the rescue strategy is governed by the duration of snow burial and, if not available, by the victim's core-temperature. If burial time ≤35 min (or core-temperature ≥32 °C) rapid extrication and standard ALS is important. If burial time >35 min and core-temperature <32 °C, treatment of hypothermia including gentle extrication, full body insulation, ECG and core-temperature monitoring is recommended, and advanced airway management if appropriate. Unresponsive patients presenting with vital signs should be transported to a hospital capable of active external and minimally invasive rewarming such as forced air rewarming. Patients with cardiac instability or in cardiac arrest (with a patent airway) should be transported to a hospital for extracorporeal membrane oxygenation or cardiopulmonary bypass rewarming. Patients in cardiac arrest should receive uninterrupted CPR; with asystole, CPR may be terminated (or withheld) if a patient is lethally injured or completely frozen, the airway is blocked and duration of burial >35 min, serum potassium >12 mmol L(-1), risk to the rescuers is unacceptably high or a valid do-not-resuscitate order exists. Management should include spinal precautions and other trauma care as indicated.
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Paal P, Strapazzon G, Braun P, Ellmauer PP, Schroeder DC, Sumann G, Werner A, Wenzel V, Falk M, Brugger H. Factors affecting survival from avalanche burial--a randomised prospective porcine pilot study. Resuscitation 2012; 84:239-43. [PMID: 22771873 DOI: 10.1016/j.resuscitation.2012.06.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 06/18/2012] [Accepted: 06/22/2012] [Indexed: 11/18/2022]
Abstract
BACKGROUND AND AIM The majority of avalanche victims who sustain complete burial die within 35min due to asphyxia and injuries. After 35min, survival is possible only in the presence of a patent airway, and an accompanying air pocket around the face may improve survival. At this stage hypothermia is assumed to be an important factor for survival because rapid cooling decreases oxygen consumption; if deep hypothermia develops before cardiac arrest, hypothermia may be protective and prolong the time that cardiac arrest can be survived. The aim of the study was to investigate the combined effects of hypoxia, hypercapnia and hypothermia in a porcine model of avalanche burial. METHODS Eight piglets were anaesthetised, intubated and buried under snow, randomly assigned to an air pocket (n=5) or ambient air (n=3) group. RESULTS Mean cooling rates in the first 10min of burial were -19.7±4.7°Ch(-1) in the air pocket group and -13.0±4.4°Ch(-1) in the ambient air group (P=0.095); overall cooling rates between baseline and asystole were -4.7±1.4°Ch(-1) and -4.6±0.2°Ch(-1) (P=0.855), respectively. In the air pocket group cardiac output (P=0.002), arterial oxygen partial pressure (P=0.001), arterial pH (P=0.002) and time to asystole (P=0.025) were lower, while arterial carbon dioxide partial pressure (P=0.007) and serum potassium (P=0.042) were higher compared to the ambient air group. CONCLUSION Our results demonstrate that hypothermia may develop in the early phase of avalanche burial and severe asphyxia may occur even in the presence of an air pocket.
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Affiliation(s)
- Peter Paal
- Department of Anesthesiology and Critical Care Medicine, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria.
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Brugger H, Paal P, Boyd J. Prehospital resuscitation of the buried avalanche victim. High Alt Med Biol 2012; 12:199-205. [PMID: 21962062 DOI: 10.1089/ham.2011.1025] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In North America and Europe, approximately 150 people die of avalanches per year, and fatalities are presumed to be many times higher in developing countries. Four factors are decisive for survival: grade of burial, duration of burial, presence of an air pocket and a free airway, and severity of trauma. According to Swiss data, the overall mortality rate with avalanche burial is 23%, but it largely depends on the grade of burial. While the mortality rate is 52.4% in completely buried (head below the snow) victims in the Swiss population, it is only 4.2% in partially buried (head free) victims. Additionally, survival in completely buried victims drops to 30% within the first 35 min, initially due to death from lethal trauma, followed by asphyxia in 20-35 min. Thereafter, survival decreases more gradually and victims who are not fatally injured and are able to breath under the snow slowly succumb to hypoxia, hypercapnia, and hypothermia. In the absence of fatal injuries, rescue strategies depend on the duration of burial and the victim's core temperature. With a burial time<35 min, survival depends on preventing asphyxia by rapid extrication, adequate airway management, and cardiopulmonary resuscitation. With a burial time>35 min, tackling hypothermia is of utmost importance. Therefore, gentle extrication and continuous core temperature and electrocardiogram monitoring are recommended. Pulseless victims with a patent airway and a core temperature<32°C should receive uninterrupted cardiopulmonary resuscitation and be transported to a hospital with extracorporeal rewarming facilities.
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Affiliation(s)
- Hermann Brugger
- Institute of Mountain Emergency Medicine, European Academy, Bozen/Bolzano, Italy.
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Affiliation(s)
- Colin K Grissom
- Department of Critical Care Medicine, Intermountain Medical Center, Murray, Utah, USA.
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Deakin CD, Morrison LJ, Morley PT, Callaway CW, Kerber RE, Kronick SL, Lavonas EJ, Link MS, Neumar RW, Otto CW, Parr M, Shuster M, Sunde K, Peberdy MA, Tang W, Hoek TLV, Böttiger BW, Drajer S, Lim SH, Nolan JP. Part 8: Advanced life support: 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science with Treatment Recommendations. Resuscitation 2011; 81 Suppl 1:e93-e174. [PMID: 20956032 DOI: 10.1016/j.resuscitation.2010.08.027] [Citation(s) in RCA: 149] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Grissom CK. Reply to Dr Muller. Wilderness Environ Med 2011. [DOI: 10.1016/j.wem.2010.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Morrison LJ, Deakin CD, Morley PT, Callaway CW, Kerber RE, Kronick SL, Lavonas EJ, Link MS, Neumar RW, Otto CW, Parr M, Shuster M, Sunde K, Peberdy MA, Tang W, Hoek TLV, Böttiger BW, Drajer S, Lim SH, Nolan JP, Adrie C, Alhelail M, Battu P, Behringer W, Berkow L, Bernstein RA, Bhayani SS, Bigham B, Boyd J, Brenner B, Bruder E, Brugger H, Cash IL, Castrén M, Cocchi M, Comadira G, Crewdson K, Czekajlo MS, Davies SR, Dhindsa H, Diercks D, Dine CJ, Dioszeghy C, Donnino M, Dunning J, El Sanadi N, Farley H, Fenici P, Feeser VR, Foster JA, Friberg H, Fries M, Garcia-Vega FJ, Geocadin RG, Georgiou M, Ghuman J, Givens M, Graham C, Greer DM, Halperin HR, Hanson A, Holzer M, Hunt EA, Ishikawa M, Ioannides M, Jeejeebhoy FM, Jennings PA, Kano H, Kern KB, Kette F, Kudenchuk PJ, Kupas D, La Torre G, Larabee TM, Leary M, Litell J, Little CM, Lobel D, Mader TJ, McCarthy JJ, McCrory MC, Menegazzi JJ, Meurer WJ, Middleton PM, Mottram AR, Navarese EP, Nguyen T, Ong M, Padkin A, Ferreira de Paiva E, Passman RS, Pellis T, Picard JJ, Prout R, Pytte M, Reid RD, Rittenberger J, Ross W, Rubertsson S, Rundgren M, Russo SG, Sakamoto T, Sandroni C, Sanna T, Sato T, Sattur S, Scapigliati A, Schilling R, Seppelt I, Severyn FA, Shepherd G, Shih RD, Skrifvars M, Soar J, Tada K, Tararan S, Torbey M, Weinstock J, Wenzel V, Wiese CH, Wu D, Zelop CM, Zideman D, Zimmerman JL. Part 8: Advanced Life Support. Circulation 2010; 122:S345-421. [DOI: 10.1161/circulationaha.110.971051] [Citation(s) in RCA: 250] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Spontaneous endogenous core temperature rewarming after cooling due to snow burial. Wilderness Environ Med 2010; 21:229-35. [PMID: 20832700 DOI: 10.1016/j.wem.2010.06.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 05/18/2010] [Accepted: 06/04/2010] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To measure afterdrop and rewarming in subjects placed in a hypothermia wrap immediately after extrication from 60 minutes of snow burial. METHODS We measured esophageal core body temperature (Tes) in 6 subjects buried in compacted snow (mean density 39%) for up to 60 minutes at an altitude of 2450 m while breathing with an AvaLung (Black Diamond Equipment, Salt Lake City, UT). Mean snow temperature was -3.5 ± 1.0 °C and mean air temperature was 0 ± 2 °C. Subjects wore a 1-piece Gore-Tex suit over medium weight Capilene underwear with a hood, face mask, goggles, mittens, and boots. After extrication from snow burial subjects were immediately placed in a hypothermia wrap. Tes was measured for an additional 60 minutes as subjects rewarmed by shivering. RESULTS Tes cooling rate during snow burial was 0.84 ± 0.3 °C/h during a mean burial time of 58 ± 4 minutes. Tes afterdrop (0.77 ± 0.4 °C) occurred 12 ± 8 minutes after extrication from snow burial at a cooling rate of 4.0 ± 0.8 °C/h (P <.001 Tes snow burial vs afterdrop cooling rate). Rewarming rate was 1.1 ± 0.3 °C/h over the subsequent 48 ± 8 minutes (P = 0.045 snow burial cooling vs rewarming rate). CONCLUSION Afterdrop rate increased about 4-fold as compared to snow burial cooling rate for a transient time period in subjects who were placed immediately into an insulating hypothermia wrap. Spontaneous endogenous rewarming increased core body temperature at a slightly higher rate than it decreased during snow burial. These findings suggest that field rewarming of mildly hypothermic and shivering avalanche burial victims is possible, but they should be insulated quickly to limit significant afterdrop.
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Boyd J, Brugger H, Shuster M. Prognostic factors in avalanche resuscitation: a systematic review. Resuscitation 2010; 81:645-52. [PMID: 20371145 DOI: 10.1016/j.resuscitation.2010.01.037] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 01/12/2010] [Accepted: 01/18/2010] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Avalanche resuscitation will save lives if focussed on victims that have the potential to survive. The purpose of this systematic review was to examine 4 critical prognostic factors for burial victims in cardiac arrest. METHODS Time of burial, airway patency, core temperature and serum potassium level were analyzed as PICO (Patient/population, Intervention, Comparator, Outcome) questions within the 2010 Consensus on Science process of the International Liaison Committee on Resuscitation. The electronic databases of Medline via PubMed, EMBASE via OVID and the Cochrane Database of Systematic Reviews were searched using combinations of the search terms "avalanche", "air pocket", "hypothermia" and "serum potassium". RESULTS Of 1910 publications that were identified 30 were found relevant. The predictive value for survival of a short time of burial or a patent airway after 35 min of burial is supported by 10 retrospective case-control studies, 4 case series and 2 experimental studies, while no studies are neutral or opposed. A core temperature of less than 32 degrees C with a patent airway is supported by 2 retrospective case-control studies and 3 case series, while 10 studies are neutral. Serum potassium level is supported by 6 retrospective case-control studies and 3 case reports, while 3 retrospective case-control studies and 1 animal model are neutral. CONCLUSION After 35 min of burial, or where the core temperature is less than 32 degrees C, a patent airway is associated with survival to hospital discharge. A serum potassium of less than 7 mmol/L may be a valuable indicator for survival when other indicators are unclear. These findings should modify the current avalanche resuscitation scheme.
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Affiliation(s)
- Jeff Boyd
- Department of Emergency Medicine, Mineral Springs Hospital, Banff, AB, Canada.
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Windsor JS, Hamilton E, Grocott MP, O'Dwyer MJ, Milledge JS. The Snow Snorkel: a proof of concept study. Wilderness Environ Med 2009; 20:61-5. [PMID: 19364164 DOI: 10.1580/08-weme-br-183.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To demonstrate that the Snow Snorkel can be used safely by healthy volunteers buried in snow for up to 1 hour. METHODS Nine healthy male volunteers were placed in a shoulder-width trench and buried with snow to a depth of 30 to 40 cm. The study was divided into 2 stages. The first stage (Stage 1) was performed with the Snow Snorkel in operation (60-minute duration) and was then followed by a second stage (Stage 2) (15-minute duration) when the device was removed. Arterial oxygen saturation (SaO2), heart rate (HR), respiratory rate (RR), axillary temperature (T), and 3-lead electrocardiography (ECG) were monitored throughout the study. RESULTS Of the 9 volunteers who were enrolled, 7 were able to complete Stage 1, while only 3 were able to complete Stage 2. In those who completed Stage 1, the mean HR fell by 14.1 beats/min (P = .002), while RR (P = .5) and SaO2 (P = .7) remained unchanged compared to baseline measurements. There were no changes in T or ECG. CONCLUSIONS Simple systems such as the Snow Snorkel are effective during snow burial and warrant further investigation.
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Affiliation(s)
- Jeremy S Windsor
- Centre for Altitude, Space and Extreme Environment Medicine, Institute of Human Health and Performance, Highgate Hill, London, UK.
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Boyd J, Haegeli P, Abu-Laban RB, Shuster M, Butt JC. Patterns of death among avalanche fatalities: a 21-year review. CMAJ 2009; 180:507-12. [PMID: 19213801 PMCID: PMC2645441 DOI: 10.1503/cmaj.081327] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Avalanches are a significant cause of winter recreational fatalities in mountain regions. The purpose of this study was to determine the relative contributions of trauma and asphyxia to avalanche deaths. METHODS We reviewed all avalanche fatalities between 1984 and 2005 that had been investigated by the offices of the British Columbia Coroners Service and the Chief Medical Examiner of Alberta. In addition, we searched the database of the Canadian Avalanche Centre for fatal avalanche details. We calculated injury severity scores for all victims who underwent autopsy. RESULTS There were 204 avalanche fatalities with mortality information over the 21-year study period. Of these, 117 victims underwent autopsy, and 87 underwent forensic external examination. Asphyxia caused 154 (75%) deaths. Trauma caused 48 (24%) deaths, with the rate of death from trauma ranging from 9% (4/44) for snowmobilers to 42% (5/12) for ice climbers. In addition, 13% (12/92) of the asphyxia victims who underwent autopsy had major trauma, defined as an injury severity score of greater than 15. Only 48% (23/48) of victims for whom trauma was the primary cause of death had been completely buried. INTERPRETATION Asphyxia and severe trauma caused most avalanche fatalities in western Canada. The relative rates differed between snowmobilers and those engaged in other mountain activities. Our findings should guide recommendations for safety devices, safety measures and resuscitation.
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Affiliation(s)
- Jeff Boyd
- Department of Emergency Medicine, Mineral Springs Hospital, Banff, Alberta
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Lawinenunfall. Rechtsmedizin (Berl) 2008. [DOI: 10.1007/s00194-008-0531-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
OBJECTIVE Avalanche fatalities occur on a yearly basis in Utah. The purpose of this study was to assess avalanche safety practices of different backcountry users in Utah and to identify groups that can be targeted for avalanche safety education. METHODS We surveyed 353 winter backcountry users to determine the percentage of participants in each group who were traveling with one or more partners; the percentage who were carrying avalanche transceivers, shovels, probes, or AvaLungs; and the percentage who had taken an avalanche safety course. A measure of minimum safe practice was defined as 1) traveling with a partner, 2) carrying an avalanche transceiver, and 3) carrying a shovel. Participants in this study were backcountry skiers, snowboarders, snowshoers, snowmobilers, and out-of-bounds resort skiers/snowboarders traveling in the Wasatch and Uinta Mountains of Utah during the winter of 2005-06. RESULTS The percentage of backcountry recreationists traveling with one or more partners was not significantly different (P=.0658) among backcountry skiers, snowboarders, snowshoers, snowmobilers, and out-of-bounds resort skiers/snowboarders. These groups did, however, differ in the percentage who carried avalanche transceivers (P<.0001), shovels (P<.0001), probes (P<.0001), and AvaLungs (P=.0020), as well as in the percentage who had taken an avalanche safety course (P<.0001) and the percentage who were carrying out minimum safe practices (P<.0001). Backcountry skiers showed the highest level of avalanche preparedness, with 98% carrying avalanche transceivers, 98% carrying shovels, 77% carrying probes, 86% having taken an avalanche safety course, and 88% carrying out minimum safe practices. Out of bounds snowboarders were the least prepared with 9% carrying avalanche transceivers, 9% carrying shovels, 7% carrying probes, 33% having taken an avalanche safety course, and 2% carrying out minimum safe practices. CONCLUSIONS There are significant differences in the avalanche safety practices of the various groups of backcountry travelers in Utah. Backcountry skiers and snowboarders were the most prepared, while snowmobilers, snowshoers, and out-of-bounds skiers/snowboarders were relatively less prepared.
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Brugger H, Etter HJ, Zweifel B, Mair P, Hohlrieder M, Ellerton J, Elsensohn F, Boyd J, Sumann G, Falk M. The impact of avalanche rescue devices on survival. Resuscitation 2007; 75:476-83. [PMID: 17689170 DOI: 10.1016/j.resuscitation.2007.06.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Revised: 05/31/2007] [Accepted: 06/07/2007] [Indexed: 10/23/2022]
Abstract
BACKGROUND Within Europe and North America, the median annual mortality from snow avalanches between 1994 and 2003 was 141. There are two commonly used rescue devices: the avalanche transceiver, which is intended to speed up locating a completely buried person, and the avalanche airbag, which aims to prevent the person from being completely buried. OBJECTIVE This retrospective study aimed to evaluate whether these avalanche rescue devices had an effect on mortality. METHODS The study population was 1504 persons who were involved in 752 avalanches either in Switzerland from 1990 to 2000 and from 2002 to 2003 (1296 persons, 86.2%) or in Austria from 1998 to 2004 (208 persons, 13.8%). RESULTS Persons equipped with an avalanche airbag had a lower chance of dying (2.9% versus 18.9%; P=0.026, OR 0.09, n=1504). In persons who were completely buried, without visible or audible signs at the surface and who did not rescue themselves (n=317), we found a lower median duration of burial (25min versus 125min; P<0.001) and mortality (55.2% versus 70.6%; P<0.001, OR 0.26) in those using an avalanche transceiver than in those not using the device. CONCLUSIONS Our data showed that both the avalanche airbag and the avalanche transceiver reduce mortality. However, to improve the evaluation of rescue devices in the future, the data collection procedures should be reviewed and prospective trials should be considered, as the reliability of retrospective studies is limited.
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Affiliation(s)
- Hermann Brugger
- International Commission for Mountain Emergency Medicine, Innsbruck Medical University, Europastrasse 17, I-39031 Bruneck, Italy.
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McIntosh SE, Grissom CK, Olivares CR, Kim HS, Tremper B. Cause of Death in Avalanche Fatalities. Wilderness Environ Med 2007; 18:293-7. [DOI: 10.1580/07-weme-or-092r1.1] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Abstract
In North America and Europe around 140 persons die every year due to avalanches, approximately 35 in North America, 100 in the European Alps, and 5 in other parts of Europe. Most of the victims are skiers and snowboarders. This article outlines the specific pathophysiology of avalanche burials, such as hypoxia, hypercapnia, and hypothermia and also other factors which influence survival. Strategies to minimize the mortality due to avalanches and the on-site treatment of buried persons are discussed. Finally, possibilities to reduce the number of avalanche deaths are pointed out.
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Affiliation(s)
- P Paal
- Universitätsklinik für Anästhesie und Intensivmedizin, Bergrettungsdienst im Alpenverein Südtirol, Internationale Kommission für alpine Notfallmedizin ICAR MEDCOM, Medizinische Universität, Innsbruck, Osterreich.
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46
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Grissom CK, Radwin MI, Scholand MB, Harmston CH, Muetterties MC, Bywater TJ. Hypercapnia increases core temperature cooling rate during snow burial. J Appl Physiol (1985) 2004; 96:1365-70. [PMID: 14660514 DOI: 10.1152/japplphysiol.00531.2003] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Previous retrospective studies report a core body temperature cooling rate of 3°C/h during avalanche burial. Hypercapnia occurs during avalanche burial secondary to rebreathing expired air, and the effect of hypercapnia on hypothermia during avalanche burial is unknown. The objective of this study was to determine the core temperature cooling rate during snow burial under normocapnic and hypercapnic conditions. We measured rectal core body temperature (Tre) in 12 subjects buried in compacted snow dressed in a lightweight clothing insulation system during two different study burials. In one burial, subjects breathed with a device (AvaLung 2, Black Diamond Equipment) that resulted in hypercapnia over 30-60 min. In a control burial, subjects were buried under identical conditions with a modified breathing device that maintained normocapnia. Mean snow temperature was -2.5 ± 2.0°C. Burial time was 49 ± 14 min in the hypercapnic study and 60 min in the normocapnic study ( P = 0.02). Rate of decrease in Tre was greater with hypercapnia (1.2°C/h by multiple regression analysis, 95% confidence limits of 1.1-1.3°C/h) than with normocapnia (0.7°C/h, 95% confidence limit of 0.6-0.8°C/h). In the hypercapnic study, the fraction of inspired carbon dioxide increased from 1.4 ± 1.0 to 7.0 ± 1.4%, minute ventilation increased from 15 ± 7 to 40 ± 12 l/min, and oxygen saturation decreased from 97 ± 1 to 90 ± 6% ( P < 0.01). During the normocapnic study, these parameters remained unchanged. In this study, Tre cooling rate during snow burial was less than previously reported and was increased by hypercapnia. This may have important implications for prehospital treatment of avalanche burial victims.
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Affiliation(s)
- Colin K Grissom
- Department of Medicine, LDS Hospital, Salt Lake City, UT 84143, USA
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47
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Brugger H, Sumann G, Meister R, Adler-Kastner L, Mair P, Gunga HC, Schobersberger W, Falk M. Hypoxia and hypercapnia during respiration into an artificial air pocket in snow: implications for avalanche survival. Resuscitation 2003; 58:81-8. [PMID: 12867313 DOI: 10.1016/s0300-9572(03)00113-8] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Snow avalanche case reports have documented the survival of skiers apparently without permanent hypoxic sequelae, after prolonged complete burial despite there being only a small air pocket on extrication. We investigated the underlying pathophysiological changes in a prospective, randomised 2 x 2 crossover study in 12 volunteers (28 tests) breathing into an artificial air pocket (1- or 2-l volume) in snow. Peripheral SpO(2), ETCO(2), arterialised capillary blood variables, air pocket O(2) and CO(2), snow density, and snow conditions at the inner surface of the air pocket were determined. SpO(2) decreased from a median of 99% (93-100%) to 88% (71-94%; P<0.001) within 4 min of breathing into the air pocket; the reduction was greater at 1 l, than 2 l, volume air pocket (P=0.013, intention to treat P=0.003) and correlated to snow density (r=0.50, P=0.021, partial correlation coefficient). ETCO(2) rose simultaneously from median 5.07 kPa (3.47-6.93 kPa) to 6.8 kPa (5.87-8.27 kPa; P<0.001), with consequent respiratory acidosis. Despite premature interruption due to hypoxia (SpO(2)</=75%) in 17 of 28 tests (61%), a respiratory steady state prevailed in five tests until protocol completion (30 min). We conclude that the degree of hypoxia following avalanche burial is dependent on air pocket volume, snow density and unknown individual personal characteristics, yet long-term survival is possible with only a small air pocket. Hence, the definition of an air pocket, "any space surrounding mouth and nose with the proviso of free air passages" is validated as the main criterion for triage and management of avalanche victims. Our experimental model will facilitate evaluating the interrelation between volume and inner surface area of an air pocket for survival of avalanche victims, whilst the present findings have laid the basis for future investigation of possible interactions between hypoxia, hypercapnia, and hypothermia (triple H syndrome) in snow burial.
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Affiliation(s)
- Hermann Brugger
- Mountain Rescue Service provided by the South Tyrolean Alpine Association, International Commission for Mountain Emergency Medicine, Europastrasse 17, I-39031 Bruneck, Italy.
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48
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Abstract
OBJECTIVE The incidence of fatal closed head injury (CHI) and nonfatal CHI causing an altered level of consciousness in avalanche victims is unknown. The purpose of this study was to assess the incidence and potential significance of CHI in avalanche-related deaths. METHODS The records of the state medical examiner and hospital records of all victims killed in avalanches in the state of Utah from October 1, 1992 through April 30, 1999 were reviewed for a cause of death and for the presence of CHI. Closed head injury was described as "present" or "severe," depending on whether the degree of CHI was sufficient to have caused or directly contributed to death, as determined by the medical examiner. RESULTS In this review, 28 avalanche-related deaths were identified, of which 22 (79%) were due to asphyxia. Seventeen victims (61%) had evidence of some degree of CHI. Six victims (21%) had evidence of severe CHI. One of 7 snowmobile riders sustained a severe CHI, whereas 4 of 16 skiers or snowboarders sustained a severe CHI (P = not significant). CONCLUSION Although asphyxiation was the cause of death in most avalanche victims, evidence of CHI was present in 61% of the cases studied. While avalanche-associated CHI may not be sufficient to cause death in many cases, a depressed level of consciousness might render a victim incapable of self-rescue and predispose to asphyxia. Helmet use may help prevent avalanche-associated CHI and thus be a useful safety adjunct.
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Affiliation(s)
- S M Johnson
- Department of Surgery, University of Utah School of Medicine, Salt Lake City, USA.
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49
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Abstract
The median annual mortality from snow avalanches registered in Europe and North America 1981-1998 was 146 (range 82-226); trend stable in Alpine countries (r=-0.29; P=0.24), increasing in North America (r=0.68; P=0.002). Swiss data over the same period document 1886 avalanche victims, with an overall mortality rate of 52.4% in completely-buried, versus 4.2% in partially-, or non-buried, persons. Survival probability in completely-buried victims in open areas (n=638) plummets from 91% 18 min after burial to 34% at 35 min, then remains fairly constant until a second drop after 90 min. Likewise, survival probability for completely-buried victims in buildings or on roads (n=97) decreases rapidly following burial initially, but as from 35 min it is significantly higher than that for victims in open areas, with a maximum difference in respective survival probability (31% versus 7%) from 130 to 190 min (P<0.001). Standardised guidelines are introduced for the field management of avalanche victims. Strategy by rescuers confronted with the triad hypoxia, hypercapnia and hypothermia is primarily governed by the length of snow burial and victim's core temperature, in the absence of obviously fatal injuries. With a burial time < or =35 min survival depends on preventing asphyxia by rapid extrication and immediate airway management; cardiopulmonary resuscitation for unconscious victims without spontaneous respiration. With a burial time >35 min combating hypothermia becomes of paramount importance. Thus, gentle extrication, ECG and core temperature monitoring and body insulation are mandatory; unresponsive victims should be intubated and pulseless victims with core temperature <32 degrees C (89.6 degrees F) (prerequisites being an air pocket and free airways) transported with continuous cardiopulmonary resuscitation to a specialist hospital for extracorporeal re-warming.
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Affiliation(s)
- H Brugger
- Alpine Rescue Service provided by the South Tyrolean Alpine Association, International Commission for Alpine Emergency Medicine, Europastrasse 17, I-39031, Bruneck, Italy.
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