Mountaineering fatalities on Aconcagua: 2001-2012

Medical Evacuations of Climbers on Mount Aconcagua, 2022-2024

IntroductionMount Aconcagua (6961 m) is the highest peak in the Western Hemisphere and attempted by over 3000 climbers annually. Aconcagua Provincial Park (APP) and the APP medical service oversee all rescues and medical care. This study aims to describe patients and conditions requiring rescue medical evacuation on Aconcagua.MethodsDemographic, medical, and logistics data provided by APP on all park evacuations were retrospectively reviewed from the 2022-23 and 2023-24 climbing seasons.ResultsOf 6494 total Aconcagua climbers over the study period, 302 required an evacuation response from APP (mean 151 per year), yielding an evacuation rate of 4.7%. Mean age was 43.0. Male climbers had twice the risk of requiring rescue than female climbers (OR 2.01). Most evacuees were European (40%) or North American (33%), though climbers from Africa, Asia, and Australia had over twice the incidence of rescue (OR 2.26). Most frequent reasons for evacuation included altitude illness of all types (62%), high-altitude pulmonary edema (HAPE) (49%), trauma/musculoskeletal (15%), general medical (11%), and acute mountain sickness (11%). Most were flown by helicopter (95%), with flight location primarily from 4200 to 4300 m base camps (77%) and between 5300 and 5970 m (16%).ConclusionsOn Aconcagua, 4.7% of climbers required medical evacuation. Altitude illness frequently required rescue, with HAPE representing the single most common reason for evacuation. Male sex and certain continents of origin showed increased risks. Helicopter evacuation and medical oversight by APP appear to contribute to climber safety on Aconcagua. Opportunities exist for future study and climber education of risks.

Emergency Care for High-Altitude Trekking and Climbing

van Veelen, Michiel J., Rudolf Likar, Markus Tannheimer, Konrad E. Bloch, Silvia Ulrich, Michael Philadelphy, Barbara Teuchner, Thomas Hochholzer, Jacqueline Pichler Hefti, Urs Hefti, Peter Paal, and Martin Burtsche. Emergency Care for High-Altitude Trekking and Climbing. High Alt Med Biol. 26:70-86, 2025. Introduction: High altitude regions are characterized by harsh conditions (environmental, rough terrain, natural hazards, and limited hygiene and health care), which all may contribute to the risk of accidents/emergencies when trekking or climbing. Exposure to hypoxia, cold, wind, and solar radiation are typical features of the high altitude environment. Emergencies in these remote areas place high demands on the diagnostic and treatment skills of doctors and first-aiders. The aim of this review is to give insights on providing the best possible care for victims of emergencies at high altitude. Methods: Authors provide clinical recommendations based on their real-world experience, complemented by appropriate recent studies and internationally reputable guidelines. Results and Discussion: This review covers most of the emergencies/health issues that can occur when trekking or during high altitude climbing, that is, high altitude illnesses and hypothermia, freezing cold injuries, accidents, for example, with severe injuries due to falling, cardiovascular and respiratory illnesses, abdominal, musculoskeletal, eye, dental, and skin issues. We give a summary of current recommendations for emergency care and pain relief in case of these various incidents.

Characteristics of Climbers with High Altitude Pulmonary Edema on Mount Aconcagua

INTRODUCTION—

Mount Aconcagua (6961 m) in Argentina is the highest peak in the Americas, and more than 3000 climbers attempt to summit annually. High altitude pulmonary edema (HAPE) is a leading cause of mortality and evacuation on Aconcagua.

OBJECTIVE—

This study sought to describe the characteristics of climbers who developed HAPE on Aconcagua to aid in future prevention efforts.

METHODS—

Climbers diagnosed with HAPE in January 2024 were surveyed regarding demographics, preparation, acclimatization, and illness. Healthy climbers on Aconcagua also were surveyed for the same period, providing a control population.

RESULTS—

Seventeen climbers were diagnosed with HAPE. These climbers were similar to climbers without HAPE in age, sex, origin, home elevation, hypoxic tent use, staged ascent, recent virus exposure, fitness metrics, and ascent-rate plans. Climbers with HAPE spent fewer nights at the 4300-m base camp (3.6 vs 5.0 nights). Prior to developing HAPE, 71% of patients reported unresolved acute mountain sickness symptoms. HAPE onset median elevation was 5500 m, with a median of 8.0 days over 3000 m and a median lowest SpO2 of 60% at diagnosis. There was a nonsignificant trend between acetazolamide use and increased HAPE. All surveyed HAPE patients descended, required helicopter evacuation, and survived.

CONCLUSION—

This study examined climbers who developed HAPE on Mount Aconcagua, yielding implications for high altitude illness prevention efforts and further study. HAPE cases were associated with insufficient nights at the 4300-m base camp and unresolved acute mountain sickness symptoms. The relationship between acetazolamide and HAPE warrants further study on Aconcagua.

Clinical outcomes of challenging out-of-hospital hypothermia management: A retrospective assessment of DOKEI protocol

BACKGROUND

Accidental hypothermia (AH) is a major cause of death in mountainous areas globally, and the second highest of mountaineering deaths in Japan, accounting for 37 % in Hokkaido. Managing AH is a significant challenge, particularly when adverse weather complicates the application of recommended rewarming and rapid transfer. To address this, the Hokkaido Police Organization (DOKEI) AH protocol was applied in Hokkaido's remote areas from 2011 to 2022, integrating high-temperature active external rewarming (HT-AER) with on-site sustained treatment.

METHODS

This study retrospectively analyzed the rescue reports and hospital records of hypothermia patients treated postprotocol, excluding patients with cold exposure, undetectable vital signs at rescue, and inadequate documentation. Protocol adherence and outcomes-hypothermia stage, cardiocirculatory collapse, survival, and neurological status-were assessed.

RESULTS

Among the 60 protocol-treated patients (19-74 years, 85 % male), 14 had stage 2 hypothermia, and 3 had stage 3 hypothermia. HT-AER was applied in 96.7 % of the patients. A total of 98.3 % of patients improved before handover without cardiac arrest (CA) or extracorporeal life support (ECLS). Comparatively, ten preprotocol patients (18-60 years, 70 % male) had two CAs, one fatal and six with no improvement.

CONCLUSION

The DOKEI AH protocol demonstrates feasibility in managing stages 1-3 hypothermia, enhancing survival and neurological recovery, and can offer a vital option in challenging AH rescue scenarios.

Frostbite and Mortality in Mountaineering Women: A Scoping Review-UIAA Medical Commission Recommendations

Kriemler, Susi, Kastė Mateikaitė-Pipirienė, Alison Rosier, Linda E. Keyes, Peter Paal, Marija Andjelkovic, Beth A. Beidleman, Mia Derstine, Jacqueline Pichler Hefti, David Hillebrandt, Lenka Horakova, and Dominique Jean; for the UIAA MedCom Writing Group on Women's Health in the Mountains. Frostbite and mortality in mountaineering women: a scoping review-UIAA Medical Commission recommendations. High Alt Med Biol. 24:247-258, 2023. Background: The harsh environment of high altitudes (HA) poses many serious health risks for mountaineers, including cold injuries and death. The aim of this work was to review whether female mountaineers are at special risk for frostbite or death at HA compared with their male counterparts. Methods: The UIAA Medical Commission convened an international author team to review women's health issues at HA and to publish updated recommendations. Pertinent literature from PubMed and Cochrane was identified with additional publications found by hand search. The primary search focus was for articles assessing cold injuries and death in women mountaineers at HA. Results: We reviewed the literature and identified 20 relevant studies: 2 studies on frostbite at HA, plus 7 studies and 1 report for death at HA. An additional 10 studies about frostbite at low altitude were included. We found that female mountaineers at HA were at lower risk of death than their male counterparts, but sex differences in frostbite were inconclusive. Conclusions: The frequency of cold injuries and mortality in female mountaineers is not yet well studied, and the studies that have been published tend to lack precise exposure data. More studies and registries with sex-differentiated data are needed.

Causes of death and characteristics of non-survivors rescued during recreational mountain activities in Japan between 2011 and 2015: a retrospective analysis

OBJECTIVES

This study aimed to describe the cause of death and characteristics at the prehospital setting associated with care and rescue processes of non-survivors rescued in the mountain of Japan.

DESIGN

Retrospective analysis.

SETTING

Prehospital setting of mountain searches and rescues in Japan. A total of 10 prefectural police headquarters with >10 cases of mountain death from 2011 to 2015.

PARTICIPANTS

Data were generated from the existing records. Of the total 6159 rescued subjects, 548 mountain deaths were caused by recreational activities.

RESULTS

Among the 548 mountain deaths, 83% were men, and major causes of death were trauma (49.1%), hypothermia (14.8%), cardiac death (13.1%) and avalanche-related death (6.6%). The alive rate at rescue team arrival in all non-survivors was 3.5%, with 1, 4 and 14 cases of cardiac, hypothermia and trauma, respectively. Cardiac deaths occurred in 93.1% (67/72) of men and individuals aged >41 years, and 88.7% (63/71) were found on mountain trails. In hypothermia, callouts were made between 17:00 and 6:00 at 49% (40/81) and by persons not on-site in 59.7% (46/77). People with >6 hours in trauma or >1 hour in cardiac death already died on rescue team arrival, but some with hypothermia after 6 hours were alive.

CONCLUSION

This study is one of the first large-scale retrospective analyses of prehospital non-survivors in mountain emergencies. The alive rate at rescue arrival in all mountain deaths was only 3.5%. These data showed that the circumstances related to onset and the process until the rescue team arrives have different characteristics, depending on the cause of death. Survival may be enhanced by targeting better use of the time before rescue team arrival and by providing further education, particularly mountain rescue-related medical problems to rescuers including bystanders.

Treatment of Cardiovascular Dysfunction With PDE5-Inhibitors - Temperature Dependent Effects on Transport and Metabolism of cAMP and cGMP

Introduction

Cardiovascular dysfunction is a potentially lethal complication of hypothermia. Due to a knowledge gap, pharmacological interventions are not recommended at core temperatures below 30°C. Yet, further cooling is induced in surgical procedures and survival of accidental hypothermia is reported after rewarming from below 15°C, advocating a need for evidence-based treatment guidelines. In vivo studies have proposed vasodilation and afterload reduction through arteriole smooth muscle cGMP-elevation as a favorable strategy to prevent cardiovascular dysfunction in hypothermia. Further development of treatment guidelines demand information about temperature-dependent changes in pharmacological effects of clinically relevant vasodilators.

Materials and Methods

Human phosphodiesterase-enzymes and inverted erythrocytes were utilized to evaluate how vasodilators sildenafil and vardenafil affected cellular efflux and enzymatic breakdown of cAMP and cGMP, at 37°C, 34°C, 32°C, 28°C, 24°C, and 20°C. The ability of both drugs to reach their cytosolic site of action was assessed at the same temperatures. IC₅₀- and K_i-values were calculated from dose–response curves at all temperatures, to evaluate temperature-dependent effects of both drugs.

Results

Both drugs were able to reach the intracellular space at all hypothermic temperatures, with no reduction compared to normothermia. Sildenafil IC₅₀ and K_i-values increased during hypothermia for enzymatic breakdown of both cAMP (IC₅₀: 122 ± 18.9 μM at 37°C vs. 269 ± 14.7 μM at 20°C, p < 0.05) and cGMP (IC₅₀: 0.009 ± 0.000 μM at 37°C vs. 0.024 ± 0.004 μM at 32°C, p < 0.05), while no significant changes were detected for vardenafil. Neither of the drugs showed significant hypothermia-induced changes in IC₅₀ and K_i–values for inhibition of cellular cAMP and cGMP efflux.

Conclusion

Sildenafil and particularly vardenafil were ableto inhibit elimination of cGMP down to 20°C. As the cellular effects of these drugs can cause afterload reduction, they show potential in treating cardiovascular dysfunction during hypothermia. As in normothermia, both drugs showed higher selectivity for inhibition of cGMP-elimination than cAMP-elimination at low core temperatures, indicating that risk for cardiotoxic side effects is not increased by hypothermia.

Mortality in Different Mountain Sports Activities Primarily Practiced in the Summer Season-A Narrative Review

Millions of people engage in mountain sports activities worldwide. Although leisure-time physical activity is associated with significant health benefits, mountain sports activities also bear an inherent risk for injury and death. However, death risk may vary across various types of mountain sports activities. Epidemiological data represent an important basis for the development of preventive measures. Therefore, the aim of this review is to compare mortality rates and potential risk factors across different (summer) mountain sports activities. A comprehensive literature search was performed on the death risk (mortality) in mountain sports, primarily practiced during the summer season, i.e., mountain hiking, mountain biking, paragliding, trekking, rock, ice and high-altitude climbing. It was found that the death risk varies considerably between different summer mountain sports. Mortality during hiking, trekking and biking in the mountains was lower compared to that during paragliding, or during rock, ice or high-altitude climbing. Traumatic deaths were more common in activities primarily performed by young adults, whereas the number of deaths resulting from cardiovascular diseases was higher in activities preferred by the elderly such as hiking and trekking. Preventive efforts must consider the diversity of mountain sports activities including differences in risk factors and practitioners and may more particularly focus on high-risk activities and high-risk individuals.

Accidental hypothermia in recreational activities in the mountains: A narrative review

The popularity of recreational activities in the mountains worldwide has led to an increase in the total number of persons exposed to cold and extreme environments through recreation. There is little conclusive evidence about the risk of hypothermia for specific activities or populations, nor is it clear which activities are represented in the literature. This is a non-systematic review of accidental hypothermia in different recreational activities in the mountains, with a specific focus on outdoor or winter activities that potentially involve cold exposure. Cases of hypothermia have been reported in the literature in mountaineering, trekking, hiking, skiing, activities performed in the backcountry, ultra-endurance events, and databases from search and rescue services that include various types of recreation. Of these activities, hypothermia as a primary illness occurs most commonly during mountaineering in the highest elevation areas in the world and during recreation practiced in more northern or remote areas. Hypothermia in skiers, snowboarders, and glacier-based activities is most often associated with accidents occurring off-piste or in the backcountry (crevasse, avalanche). Organizers of outdoor events also have a role in reducing the incidence of hypothermia through medical screening and other preparedness measures. More complete collection and reporting of data on mild hypothermia and temperature measurement would improve our understanding of the incidence of hypothermia in outdoor recreation in future.