High altitude mountaineering
Under high mountain climbing mountain climbing a mountain is understood at higher altitudes. It requires the adaptation of the organ systems to the corresponding altitude in order to be able to compensate for the reduced oxygen supply. Only in this way can the risk of edema ( pulmonary edema and brain edema ) be avoided as far as possible with increased physical strain (passive) and exertion (active), especially from around 7000 m .
Height adjustment
The higher the target altitude, the longer the adaptation time ( acclimatization ) to the altitude. The adjustment time varies from person to person and is not directly linked to other physical fitness: There are people who are unsportsmanlike who have the natural ability to double the concentration of erythrocytes (red blood cells, the carriers of oxygen); they can therefore stay longer at high altitudes. With other people, the concentration does not increase as much even after prolonged adaptation - even if they are very sporty and well-trained.
This adaptive performance can be determined in advance by sports medicine within certain limits, but the “truth” only becomes apparent on site, when coping with exertion with reduced oxygen partial pressure at high altitude. This topic becomes particularly important on expedition trips, where customers with limited mountaineering experience are offered the organization and logistics as well as guided climbing of the highest mountains. An extreme example of this are the guided tours on Mount Everest . The special items of equipment include an oxygen mask with valves and regulators as well as a corresponding number of oxygen cylinders, which are usually brought to high-altitude storage by porters. About 100 people have now been able to climb Mount Everest without additional oxygen, but the physical ability to do so is very rare. As a rule, tourist mountaineers use bottled oxygen above 7500 meters, between 1.5 and 2.5 liters per minute. This corresponds to the need for two bottles of oxygen in 24 hours. In the area of top mountaineering, the use of additional oxygen is now rejected because a training-based ascent of the eight-thousander has proven to be feasible and the physiological use of oxygen only corresponds to that when climbing a seven-thousander. Oxygen aid (a kind of doping) is only accepted in medical emergencies due to the sporting aspects of a fair performance comparison.
Planning an expedition at high altitudes requires a carefully worked out plan for acclimatization . This includes staying at a great height without physical exertion. An altitude adjustment is necessary from around 3000 meters if you want to stay at this altitude permanently. The rule of thumb is to only climb about 300 meters a day. The second step of acclimatization takes place in the base camps , which are located in the Himalayas at an altitude between 4200 and 5500 meters and thus allow a stay of several weeks. Starting from the base camp, individual tours are undertaken to reach greater heights, which serve to acclimatise and, in the case of guided tours, at the same time to assess the participants by their mountain guides, to what extent they will probably be able to cope with the demands of even greater heights. The time required for acclimatization to climb an eight-thousander is often more than eight weeks.
Death zone
The term death zone was coined by the expedition doctor on the Swiss Everest expedition in 1952. It describes staying at heights above 7000 meters. This is the approximate limit above which an optimally acclimatized person can no longer regenerate without further physical exertion. From 7000 m height is in the alveoli of the critical oxygen partial pressure of 30 to 35 mm Hg (40 to 47 hPa) below. Below this value, the oxygen saturation of hemoglobin in the arterial blood falls below a tolerable value. The body inevitably degrades in such a way that permanent residence is impossible, as one would die from altitude sickness . The region above 8000 meters is often referred to as the death zone, in which survival is extremely unlikely if a stay of more than 48 hours is present. The fact that an Italian mountaineer survived four nights on Mount Everest in 2012 at an altitude of over 8,000 meters is therefore considered a very big exception.
Other risks
Due to the weather conditions at extreme heights (cold, high wind speeds, gusts, high-altitude storms, sudden falls) there is always criticism of the agencies' promises of success, which often advertise with a guarantee of reaching the summit.
The low temperatures and the "window" of reasonably stable weather conditions that only open a few days a year, the exhausting day-long ascent and the need to at least carry personal items with you, the constant alternation of walking on the rocks and on the ice as well as the resulting possibility of serious missteps conceal in the Sum up a considerable risk potential. As a result of these factors, the attempt to climb an eight-thousander is associated with an extremely high risk of death. The exertion can also be seen in the extreme weight loss: Acquirers of an eight-thousander lost at least 15 kg, but often also 30 kg, on an expedition lasting several weeks.
In the upper area of mountains such as Mount Everest, there is still an additional risk of life threatening due to unforeseeable events (such as rapidly changing weather conditions). People die there, the vast majority of whom did not act lightly, but were well prepared and trained, but who had an accident in the interplay of several incidents, for example due to a sudden sudden fall in the weather or an accidental equipment failure. The psyche is also heavily stressed, because the ascent into the death zone can lead to an encounter with the unsecured corpses of previous climbers. Clear thinking is severely impaired or slowed down by the lack of oxygen and dehydration. Because of the cold, the mountain air is very dry. As a result, the body loses so much water through breathing that around seven liters of water are required every day. Often, exhaustion and waning alertness mean that a threatening lack of water is not noticed. In addition, the urgent motivation to want to reach the prominent summit at any cost can result in the fact that forces actually still needed for the descent are invested completely or alarming physical signals are ignored. Many mountaineers did not fall to their death during difficult climbing passages or were swept away by avalanches, but died of exhaustion on the descent. The lack of decision-making competence due to the acute lack of oxygen can play a fatal role here.
Due to the lack of sufficient oxygen, water and food, the metabolism of the human body is reduced to a minimum. The supply of the extremities is reduced beforehand. Therefore, the risk of frostbite on toes and fingers increases. Due to the reduced metabolism, the body also benefits to a lesser extent from its waste heat, which makes it difficult to maintain the body temperature that is essential for life.
Challenges
There are different challenges in high altitude mountaineering. Climbing a certain collection of peaks is widespread, the top priority being the ascent of all 14 eight-thousanders in the world. Reinhold Messner was the first person to do that in 1986; In the meantime, another 29 people have achieved this goal. A little less difficult and dangerous is the ascent of the Seven Summits , the highest mountains on each continent. Several hundred people have achieved this goal to date. Much more challenging than the Seven Summits is the goal of climbing the second highest mountains on all continents ( Seven Second Summits ), as they are technically more difficult and more dangerous than the highest mountains.
Ascent of the 14 eight-thousanders, the Seven Summits and the Seven Second Summits, which are completed in the most sporty climbing style possible (e.g. alpine style ), on difficult or new routes and in the case of the eight-thousanders without additional oxygen, are also considered to be of higher value . Most climbers who work through one of these summit lists commit the normal routes, take advantage of the expedition style and use bottled oxygen on the eight-thousanders. First ascents no longer play an essential role in modern high-altitude mountaineering, as the few as yet unclimbed mountains are mostly not allowed to be climbed for religious or military reasons (e.g. Gangkhar Puensum ). First ascents of new routes on the eight-thousanders and on difficult walls of seven- and six-thousanders, on the other hand, are still possible today in very large numbers and place the highest demands on the alpinists involved, especially if they are reached in the easiest and sporty style possible. Three of the five Pakistani eight-thousanders have never been climbed in winter. This is also considered to be an extreme challenge, as well as walking difficult routes (or new routes) on your own.
Other important challenges in high-altitude mountaineering are speed climbs (so-called "skyrunning"), complete ski runs, crossings and enchaînements, carried out on eight-thousanders. For the correct evaluation of the individual services, the consideration of the route, the walking style and the documentation of the aids used (bottled oxygen, external help, fixed ropes, etc.) are decisive. For example, crossing an eight-thousander in alpine style is usually rated significantly higher than a speed ascent on the groomed normal route. Today there are a large number of records in high altitude mountaineering, the importance of which is usually minor for alpinism. They primarily aim to market the respective protagonists.
See also
Web links
- International Society for Mountain Medicine
- Thomas Lämmle - Altitude Tactics [1]
- Thomas Lämmle - Altitude Medicine [2]
Individual evidence
- ↑ The Everest Experiment: Mountaineers as a Model of Pulmonary Hypertension Disease ( Memento from September 27, 2007 in the Internet Archive ) Website of the University of Gießen (de.)
- ↑ a b Stephan Orth: Mountain drama in the Himalayas: Another German dies on Mount Everest. In: Der Spiegel . May 24, 2012, accessed April 7, 2019 .