1
|
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.
Collapse
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
| |
Collapse
|
2
|
Lugnet V, McDonough M, Gordon L, Galindez M, Mena Reyes N, Sheets A, Zafren K, Paal P. Termination of Cardiopulmonary Resuscitation in Mountain Rescue: A Scoping Review and ICAR MedCom 2023 Recommendations. High Alt Med Biol 2023; 24:274-286. [PMID: 37733297 DOI: 10.1089/ham.2023.0068] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/22/2023] Open
Abstract
Lugnet, Viktor, Miles McDonough, Les Gordon, Mercedes Galindez, Nicolas Mena Reyes, Alison Sheets, Ken Zafren, and Peter Paal. Termination of cardiopulmonary resuscitation in mountain rescue: a scoping review and ICAR MedCom 2023 recommendations. High Alt Med Biol. 24:274-286, 2023. Background: In 2012, the International Commission for Mountain Emergency Medicine (ICAR MedCom) published recommendations for termination of cardiopulmonary resuscitation (CPR) in mountain rescue. New developments have necessitated an update. This is the 2023 update for termination of CPR in mountain rescue. Methods: For this scoping review, we searched the PubMed and Cochrane libraries, updated the recommendations, and obtained consensus approval within the writing group and the ICAR MedCom. Results: We screened a total of 9,102 articles, of which 120 articles met the inclusion criteria. We developed 17 recommendations graded according to the strength of recommendation and level of evidence. Conclusions: Most of the recommendations from 2012 are still valid. We made minor changes regarding the safety of rescuers and responses to primary or traumatic cardiac arrest. The criteria for termination of CPR remain unchanged. The principal changes include updated recommendations for mechanical chest compression, point of care ultrasound (POCUS), extracorporeal life support (ECLS) for hypothermia, the effects of water temperature in drowning, and the use of burial times in avalanche rescue.
Collapse
Affiliation(s)
- Viktor Lugnet
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Department of Anesthesiology and Intensive Care, Östersund Hospital, Östersund, Sweden
- Swedish Mountain Guides Association (SBO), Gällivare, Sweden
| | - Miles McDonough
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Department of Emergency Medicine, UCSF Fresno, Fresno, California, USA
| | - Les Gordon
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Langdale Ambleside Mountain Rescue Team, Ambleside, United Kingdom
- Department of Anaesthesia, University Hospitals of Morecambe Bay Trust, Lancaster, United Kingdom
| | - Mercedes Galindez
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Department of Internal Medicine, Hospital Zonal Ramón Carrillo, San Carlos de Bariloche, Argentina
- Comisión de Auxilio Club Andino Bariloche, San Carlos de Bariloche, Argentina
| | - Nicolas Mena Reyes
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Department of Emergency Medicine, Sótero del Río Hospital, Santiago de Chile, Chile
- Grupo de Rescate Médico en Montaña (GREMM), Santiago, Chile
- Emegency Medicine Section, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alison Sheets
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Emergency Medicine, Boulder Community Health, Boulder, Colorado, USA
- Wilderness Medicine Section, University of Colorado Health Sciences Center, Aurora, Colorado, USA
| | - Ken Zafren
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Himalayan Rescue Association, Kathmandu, Nepal
- Department of Emergency Medicine, Stanford University Medical Center, Stanford, California, USA
- Alaska Native Medical Center, Anchorage, Alaska, USA
| | - Peter Paal
- International Commission for Mountain Emergency Medicine (ICAR MedCom), Kloten, Switzerland
- Department of Anaesthesiology and Intensive Care Medicine, St. John of God Hospital, Paracelsus Medical University, Salzburg, Austria
| |
Collapse
|
3
|
Libersa M, Marxer L, Zafren K, Oggier S, Pucci L, Pasquier M. Takotsubo Cardiomyopathy Following Complete Avalanche Burial: A Case Report. High Alt Med Biol 2023; 24:149-151. [PMID: 37262197 DOI: 10.1089/ham.2023.0026] [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] [Indexed: 06/03/2023] Open
Abstract
Libersa, Marie, Louis Marxer, Ken Zafren, Stephane Oggier, Lorenzo Pucci, and Mathieu Pasquier. Takotsubo cardiomyopathy following complete avalanche burial: a case report. High Alt Med Biol. 24:149-151, 2023.-Takotsubo cardiomyopathy is a transient left ventricular dyskinesia triggered by a stressful physical or emotional event. We report a case of mid-ventricular Takotsubo stress cardiomyopathy in an avalanche victim. The patient was a 41-year-old woman who was completely buried under 1.2 m of snow for 30 minutes. On arrival at the hospital, she was conscious and hypothermic (core temperature 33.7°C). Her ECG showed rapid atrial fibrillation (142 beats/min) that converted to sinus rhythm after rewarming and administration of crystalloids. Echocardiography showed akinesia of the left mid-ventricle with a left ventricular ejection fraction of 41%. At 48-hour follow-up, echocardiography showed an almost complete recovery. During her hospital stay the patient was diagnosed with an acute stress disorder with symptoms of dissociation. She was discharged home after 5 days. At 2-week follow-up echocardiography was normal. Psychological follow-up was normal at 7 months. The physical and psychological stress of the avalanche, as well as hypothermia, were all possible triggers of Takotsubo cardiomyopathy.
Collapse
Affiliation(s)
- Marie Libersa
- Intensive Care Department, Valais Hospital, Sion, Switzerland
| | - Louis Marxer
- Department of Anesthesiology, Valais Hospital, Viège, Switzerland
| | - Ken Zafren
- Department of Emergency Medicine Stanford University Medical Center, Stanford, California, USA
- Department of Emergency Medicine, Alaska Native Medical Center, Anchorage, Alaska, USA
| | | | - Lorenzo Pucci
- Honorary Fellow, Royal Brompton and Harefield Hospitals, London, United Kingdom
| | - Mathieu Pasquier
- Emergency Department, Lausanne University Hospital, Lausanne, Switzerland
| |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
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.
Collapse
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.
| |
Collapse
|
6
|
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.
Collapse
|
7
|
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.
Collapse
|
8
|
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]
|
9
|
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.
Collapse
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
| |
Collapse
|
10
|
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
| |
Collapse
|
11
|
Strapazzon G, Brugger H, Paal P, Brown D. Reconsidering the air pocket around mouth and nose as a positive outcome predictor in completely buried avalanche victims. Resuscitation 2020; 152:208-209. [PMID: 32229217 DOI: 10.1016/j.resuscitation.2020.02.043] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 02/02/2020] [Indexed: 10/24/2022]
Affiliation(s)
- Giacomo Strapazzon
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; International Commission for Alpine Emergency Medicine (ICAR MEDCOM), Kloten, Switzerland.
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; International Commission for Alpine Emergency Medicine (ICAR MEDCOM), Kloten, Switzerland
| | - Peter Paal
- International Commission for Alpine Emergency Medicine (ICAR MEDCOM), Kloten, Switzerland; Department of Anaesthesiology and Intensive Care Medicine, St. John of God Hospital, Paracelsus Medical University, Salzburg, Austria
| | - Doug Brown
- International Commission for Alpine Emergency Medicine (ICAR MEDCOM), Kloten, Switzerland; Department of Emergency Medicine, Royal Columbian Hospital, University of British Columbia, Vancouver, Canada
| |
Collapse
|
12
|
Rafl J, Kulhanek F, Kudrna P, Ort V, Roubik K. Response time of indirectly accessed gas exchange depends on measurement method. BIOMED ENG-BIOMED TE 2018; 63:647-655. [PMID: 28802098 DOI: 10.1515/bmt-2017-0070] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Accepted: 07/03/2017] [Indexed: 11/15/2022]
Abstract
Noninvasive techniques are routinely used for assessment of tissue effects of lung ventilation. However, comprehensive studies of the response time of the methods are scarce. The aim of this study was to compare the response time of noninvasive methods for monitoring of gas exchange to sudden changes in the composition of the inspired gas. A prospective experimental study with 16 healthy volunteers was conducted. A ventilation circuit was designed that enabled a fast change in the composition of the inspiratory gas mixture while allowing spontaneous breathing. The volunteers inhaled a hypoxic mixture, then a hypercapnic mixture, a hyperoxic mixture and finally a 0.3% CO mixture. The parameters with the fastest response to the sudden change of O2 in inhaled gas were peripheral capillary oxygen saturation (SpO2) and regional tissue oxygenation (rSO2). Transcutaneous oxygen partial pressure (tcpO2) had almost the same time of reaction, but its time of relaxation was 2-3 times longer. End-tidal carbon dioxide (EtCO2) response time to change of CO2 concentration in inhaled gas was less than half in comparison with transcutaneous carbon dioxide partial pressure (tcpCO2). All the examined parameters and devices reacted adequately to changes in gas concentration in the inspiratory gas mixture.
Collapse
Affiliation(s)
- Jakub Rafl
- Czech Technical University in Prague, Faculty of Biomedical Engineering, Department of Biomedical Technology, nam. Sitna 3105, 272 01 Kladno, Czech Republic, Phone: +420 728 229 991, Fax: +420 224 358 419
| | - Filip Kulhanek
- Czech Technical University in Prague, Faculty of Biomedical Engineering, Department of Biomedical Technology, 272 01 Kladno, Czech Republic
| | - Petr Kudrna
- Czech Technical University in Prague, Faculty of Biomedical Engineering, Department of Biomedical Technology, 272 01 Kladno, Czech Republic
| | - Vaclav Ort
- Czech Technical University in Prague, Faculty of Biomedical Engineering, Department of Biomedical Technology, 272 01 Kladno, Czech Republic
| | - Karel Roubik
- Czech Technical University in Prague, Faculty of Biomedical Engineering, Department of Biomedical Technology, 272 01 Kladno, Czech Republic
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
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.
Collapse
|
15
|
[Not Available]. High Alt Med Biol 2016; 17:57-60. [PMID: 27281470 DOI: 10.1089/ham.2016.29010.stg] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|