Rescue Emergencies Due to High-Altitude Illnesses Are Rare in Switzerland

Background: Despite a potential high risk of acute mountain sickness (AMS) in the Swiss Alps, there is a lack of analyses concerning its relevance over longer periods. In consequence, the aim of this study is to analyze the prevalence of AMS in comparison to other causes of mountain emergencies in recent years in Switzerland. Material and Methods: Based on the central registry of mountain emergencies of the Swiss Alpine Club (SAC), all cases in the period between 2009 and 2020 were analyzed for AMS including the most severe forms of high-altitude pulmonary edema (HAPE) and high-altitude cerebral edema (HACE). Emergencies were assessed for the severity of the event with a National Advisory Committee for Aeronautics (NACA) score. Results: From a total of 4596 high-altitude mountaineering emergencies identified in the observational period, a total number of 352 cases of illnesses were detected. Detailed analysis revealed 85 cases of AMS, 5 cases of HAPE, and 1 case of HACE. The average altitude was 3845 ± 540 m. Most cases were in the canton of Valais, especially in the Monte Rosa region and the mountains of the Mischabel group (Täschhorn, Dom, Südlenz, Nadelhorn, Hohberghorn). There were only three deaths related to high-altitude illnesses; all the other events could be identified as moderate to severe but not life-threatening. Discussion: An emergency due to AMS that requires rescue is unlikely in the Swiss Alps. This does not imply that AMS is not a concern. However, the facts that the maximal altitude is relatively low and that fast self-descents often seem possible probably minimize the likelihood that mountaineers with symptoms contact emergency services.

Hypoxia Conditioning for High-Altitude Pre-acclimatization

Purpose Main purposes of pre-acclimatization by hypoxia conditioning (HC) are the prevention of high-altitude illnesses and maintenance of aerobic exercise performance. However, robust evidence for those effects or evidence-based guidelines for exposure strategies, including recommendations to ensure safety, are largely lacking. Therefore, we summarize the current knowledge on the physiology of acclimatization to hypoxia and HC with the aim to derive implications for pre-acclimatization strategies before going on high-altitude treks and expeditions. Methods Based on the literature search and personal experience, core studies and important observations have been selected in order to present a balanced view on the current knowledge of high-altitude illnesses and the acclimatization process, specifically focusing on pre-acclimatization strategies by HC. Results and Conclusions It may be concluded that in certain cases even short periods (e.g., 7 h) of pre-acclimatization by HC are effective, but longer periods (e.g., > 60 h) are needed to elicit more robust effects. About 300 h of HC (intermittently applied) may be the optimal preparation for extreme altitude sojourns, although every additional hour spent in hypoxia may confer further benefits. The inclusion of hypobaric exposures (i.e., real altitude) in pre-acclimatization protocols could further increase their efficacy. The level of simulated altitude is progressively increased or individually adjusted ideally. HC should not be terminated earlier than 1–2 weeks before altitude sojourn. Medical monitoring of the pre-acclimatization program is strongly recommended.

Metabolomics affirms traditional alcoholic beverage raksi as a remedy for high-altitude sickness

Raksi, a fermented distilled alcoholic beverage, is an ethnic drink consumed in high altitude regions of Singalila Ridge of the Himalayas and in adjoining high altitude places in Nepal, northern and north eastern part of India and Tibetan plateau. Like jaanr, tongba, nigar, chhyang, and other fermented ethnic beverages, raksi is considered as an element of ethnopharmacology of high altitude with claims of medicinal properties. An ethnobiological survey was done in the study area prior to collection and identification of raksi samples. In this research, two raksi samples (khokim raksi and chimphing raksi) of Singalila Ridge of the Himalayas were investigated by metabolite profiling using gas chromatography-mass spectrometry analysis. Results of the experiment showed presence of several respiratory protective, cardioprotective, neuroprotective, anti-inflammatory, and antioxidant components which have properties to prevent various high altitude illnesses. Moreover, large quantities of bioactive terpenoids, fatty acid derivatives, coumarins, and peptides were detected whose chemotaxonomy and biosynthesis pathways were further studied. This metabolomics investigation not only affirmed Raksi as a remedy for high-altitude sickness but also helped in understanding the importance of this type of ethnic foods in high altitude ethnoecology. This research on raksi in the fields of ethnobiology and metabolomics is a cumulative approach which has opened the door for in-depth investigations on similar ethnic foods. However, further experiments on raksi are surely needed in ethnobiology, microbiology, biochemistry, and food technology.

High Altitude Illness

Key Points Individuals traveling to high altitudes (usually to ≥2,500 m) are at risk of developing high altitude illness (HAI), especially if ascending quickly.Acclimatization and slow ascent are the most effective ways to avoid HAI.Acetazolamide is prevention and treatment.High altitude illnesses typically respond to descent, oxygen therapy, or both.

Mountain neurology

Mountain climbers may develop specific illnesses that largely depend on the altitude reached and the rate of ascent. The popularity of travel to high altitude destinations, extreme tourist activities and mountain climbing means that neurologists in low-altitude countries are increasingly likely to encounter neurological problems and disorders in people exposed to high altitude. Additionally, they may have to advise patients with pre-existing neurological conditions on the risks of ascent to altitude. This article focuses on neurological-related high-altitude illnesses: acute mountain sickness and high-altitude cerebral oedema, as well as high-altitude retinopathy and other neurological disorders. This overview combines current understood pathogenesis with the experience of managing altitude-related illness at the foot of Mount Kilimanjaro in northern Tanzania, the tallest free-standing mountain in the world.