Altitude Sickness: Causes, Signs and symptoms and Diagnosis

Altitude Sickness: Causes, Signs and symptoms and Diagnosis


MNT Knowledge Center

Altitude sickness can also be known as acute mountain sickness (AMS), altitude illness, hypobaropathy, Acosta disease, puna and soroche. It’s a disorder brought on by staying at thin air where air pressure is low without prior acclimatization (the entire process of gradual exposure).

If altitude sickness does occur, it’ll achieve this at altitudes above 8,000 ft (2,500 meters) – 8,000 meters is a very common height for a lot of ski resorts.

More serious signs and symptoms generally occur at above 3,600 meters (about 12,000 ft). Acute mountain sickness can progress to thin air lung edema (HAPE) or thin air cerebral edema (HACE).

Individuals with altitude sickness normally have a poor headache, nausea, dizziness and feel exhausted. In the following paragraphs, we’ll consider the causes, signs and symptoms, diagnosis, prevention and treatment of altitude sickness.

Contents want to know ,:

  1. Symptoms and causes of altitude sickness
  2. Diagnosis, treatment, complications and prevention of altitude sickness

Fast details on altitude sickness

Here are a few tips about altitude sickness. More detail and supporting information is incorporated in the primary article.

  • At higher elevations, the number of oxygen molecules per breath decreases
  • Rising to a high level without acclimatizing can cause fluid to build up in the lungs and brain
  • Once above 3,000 meters, about 75% of people will experience mild altitude sickness
  • Symptoms of altitude sickness include weakness, sleepiness and lack of appetite
  • The main causes are climbing to a great height too quickly or staying at that height for too long
  • Some evidence suggests there is a genetic component to altitude sickness
  • Diagnosis of altitude sickness only requires gathering information about the patient’s recent history
  • There are a number of treatments for altitude sickness, but, firstly, the individual should slowly descend
  • To prevent altitude sickness, it is vital to acclimatize before ascending.

What’s altitude sickness?

[Mountaineers on a mountain]

The greater one climbs, the less oxygen is drawn in per inhalation.

At ocean level the atmospheric power of oxygen is approximated 21% and also the barometric pressure averages 760 mmHg.

At greater altitudes the 21% continues to be the same however the amount of oxygen molecules per breath is reduced.

At approximately 5,500 meters (18,000ft) each breath contains roughly half the standard quantity of oxygen (when compared with ocean level).

To be able to make amends for the oxygen shortfall the individual needs to breathe faster as well as their heart needs to beat faster too.

Despite the fact that breathing faster raises bloodstream oxygen levels, they don’t achieve ocean level concentrations.

Rising to greater altitudes may also cause fluid to leak from small bloodstream vessels (capillaries), leading to potentially harmful fluid accumulation within the lung area and/or even the brain. If your human continues rising to greater altitudes without sufficient acclimatization, there’s a significant chance of existence-threatening illnesses.

Researchers in the College of Edinburgh discovered that many mountain climbers have a tendency to underestimate the chance of developing acute mountain sickness.1

Based on the British Nhs (NHS):

  • Mountain sickness is fairly common among skiers, mountaineers and people who spend time at high altitudes
  • At a height of over 3,000 meters (10,000 feet) about three-quarters of people will experience mild symptoms
  • 20% to 25% of Colorado (USA) skiers and 53% of Periche (Nepal) trekkers develop symptoms of altitude sickness
  • About 34% of people in the Swiss Alps who ascend to 3,600 meters (about 12,000 feet) or more experience some degree of altitude sickness.

It’s not easy to get altitude sickness in places such as the United kingdom that don’t have regions of always high elevation. Ben Nevis in Scotland – britain’s greatest mountain – is 1,344 meters (4,406 ft) high. Regardless of how fast you increased that mountain, you wouldn’t get altitude sickness.

Chronic mountain sickness versus. acute mountain sickness?

Chronic mountain sickness, also referred to as Monge’s disease, develops after working a long time living at thin air (over 3,000 meters). Acute mountain sickness has experience soon after climbing too quickly to some thin air.

Signs and symptoms of altitude sickness

Harshness of signs and symptoms so when they start rely on several factors, including:

  • The person – age, weight, blood pressure, general fitness, etc.
  • The speed at which people ascended
  • How long was spent at high altitude.

The main symptom to identify altitude sickness is really a headache. However, certainly one of dehydration’s signs and symptoms can also be headache.

Therefore, for correct diagnosis, experts repeat the patient must be in a height with a minimum of 2,500 meters (8,000 ft), includes a headache, in addition to a minumum of one from the signs and signs and symptoms the following:

  • Lack of appetite, nausea, or vomiting
  • Exhaustion or weakness
  • Dizziness (light-headedness)
  • Insomnia
  • Pins and needles
  • Panting (shortness of breath) upon exertion
  • Feeling sleepy (drowsiness)
  • General malaise
  • Swelling of the hands, feet and face (peripheral edema).

The following signs and symptoms may indicate something more serious, perhaps a life-threatening altitude sickness:

  • Fluid in the lungs (high altitude pulmonary edema):
    • Persistent dry cough, often with pinkish sputum
    • Fever
    • Panting (even while resting).


  • Swelling of the brain (high altitude cerebral edema)
    • Persistent headache. Painkillers do not get rid of the pain
    • Unsteady gait, clumsiness
    • Increased vomiting
    • Gradual loss of consciousness
    • Numbness, and dizziness.


Reasons for altitude sickness

The primary reason for altitude sickness is climbing too quickly. It could also be brought on by going excessive and remaining there for too lengthy.

[Climber facing steep rock climb]

The body needs time to adjust to altitude.

The body needs to adjust to the low air pressure and decreased amounts of oxygen – for your it requires a gentle progression (acclimatization).

The typical body needs from 1-three days to obtain acclimatized to a general change in altitude.

People who don’t spend sufficient time acclimatizing to a different altitude prior to going further up possess the greatest chance of developing altitude sickness.

Altitude sickness – our reaction to a lesser oxygen supply towards the muscles and brain – may become a significant and fatal condition.

If there’s less oxygen within the bloodstream, the center and lung area need to continue to work harder, raising the heart beat and breathing rates. More red bloodstream cells are created to let the body to hold more oxygen. As our physiques react to a general change in altitude our bloodstream acidity level, lung pressure, electrolyte levels and fluid and salt balance change.

Chronic mountain sickness seems to possess a genetic component2 – a group in the College of California-North Park learned that two genes – ANP32D and SENP1 – tend to be more common in individuals who are afflicted by chronic mountain sickness.

Calculating specific, exercise-related responses helps predict severe thin air sickness3 – researchers in the Universit√© Paris, France, reported within the American Journal of Respiratory system and demanding Care Medicine they could determine who’s more prone to develop severe thin air sickness by calculating oxygen desaturation at exercise and a few other exercise-related body responses.

Around the next page, we glance at diagnosis, treatment, complications and protection against altitude sickness.


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Diagnosing altitude sickness

If an individual has rose for an altitude above 2,500 ft, there is a headache plus a minumum of one from the signs and symptoms in the above list, then a precise diagnosis is rather straightforward.

The very first signs and symptoms of altitude sickness are usually headaches, light-headedness, exhaustion, insomnia and stomach upset.

Anybody who develops these signs and symptoms should immediately stop climbing, or perhaps go lower to some lower level and rest until signs and symptoms have completely gone.

Treatments for altitude sickness

[Climber from above climbing cliff]

Maintaining fluid intake is imperative when the signs and symptoms of altitude sickness appear.

The twelve signs and signs and symptoms of altitude sickness shouldn’t be overlooked, since the potential complications from the condition might be fatal.

Dying from altitude sickness was once a lot more common, due to the fact people didn’t place the twelve signs or signs and symptoms (or made the decision to disregard them).

Individuals with very mild signs and symptoms may continue climbing, but in a much slower pace. You should let others be aware of signs and symptoms exist, regardless of how mild they could be.

Individuals with a little more severe signs and symptoms should:

  • Rest completely
  • Consume plenty of (non-alcoholic) fluids
  • Not smoke.

Climbing down: climbing down to some lower altitude is most likely the very best factor to complete if signs and symptoms develop. Tries to treat or stabilize the individual in situ at altitude is harmful, unless of course highly controlled with good medical facilities. Individuals with moderate signs and symptoms usually respond well when they descent just 1,000 ft (300 meters) and remain there for twenty-four hrs. When the individual with moderate signs and symptoms remains only at that lower altitude for a few days themselves may have become acclimatized plus they may then start climbing again.

Individuals with severe signs and symptoms should descend a minimum of 2,000 ft (600 meters) as quickly as possible. If this isn’t done rapidly there’s a danger of significant of existence-threatening complications. People whose signs and symptoms don’t improve after climbing down 600 meters is going lower further until they begin feeling better.

Pure oxygen: giving pure oxygen to someone with severe difficulty in breathing brought on by altitude sickness might help. Oxygen is generally supplied by physicians at mountain resorts.

Gamow bag: this really is used whenever a rapid descent isn’t feasible. It’s a portable plastic hyperbaric chamber inflated having a feet pump. You can use it to lessen the effective altitude by as much as 1,500 meters (5,000 ft). It is almost always utilized as a guide to evacuate patients with severe signs and symptoms, to not treat them at thin air.

Coca plant: this can be a folk fix for altitude sickness in Ecuador, Peru and Bolivia. A tea is made of the coca plant.

Painkillers: Tylenol (paracetamol) could be taken for headaches. Researchers in the Stanford College Med school reported in Annals of Emergency Medicine that more than-the-counter ibuprofen is effective4 for the signs and symptoms of altitude sickness.

Acetazolamide: medicines corrects caffeine imbalance within the bloodstream brought on by altitude sickness, in addition to speeding up a person’s breathing rate. When the person can breathe more rapidly themselves may have more oxygen, leading to an alleviation of some signs and symptoms, for example nausea, dizziness and headache. Medicines has some possible negative effects, including pins-and-needles evidently, fingers and toes, excessive peeing, and blurred vision (rare).

Dexamethasone: a powerful synthetic person in the glucocorticoid type of steroid hormones. It functions being an anti-inflammatory and immunosuppressant. Its potency is all about 20-30 occasions those of hydrocortisone and 4-5 occasions of prednisone. It’s an effective medication to treat cerebral edema, among the complications of altitude sickness – it cuts down on swelling (inflammation) from the brain. Patients usually receive an improvement within roughly six hrs. Medicines has some possible negative effects, including stomach upset, depression and excitement.

Nifedipine: a dihydropyridine calcium funnel blocker, generally used to treat hypertension (high bloodstream pressure). It’s good at treating lung edema (fluid accumulation within the lung area). Medicines cuts down on the narrowing from the lung artery, leading to less chest tightness and simpler breathing. As bloodstream pressure can all of a sudden drop after using this medication, people are advised to not wake up too rapidly.

Complications of altitude sickness

[Climber has climbed a hill]
Consuming the right amount of calories is important at altitude.

The two main altitude sickness complications are:

    • High altitude cerebral edema (HACE): a lack of oxygen causes fluid to leak through tiny blood vessels (capillaries) and into the brain, which swells. Usually, HACE occurs when somebody stays at high altitude for at least one week.

      If left untreated death is likely. The patient should be descended by at least 600 meters (2,000 feet) immediately.

      A team from the University Hospitals in Goettingen and Heidelberg, Germany, found that MRI (magnetic resonance imaging) demonstrated that many mountain climbers with HACE had traces of bleeding in the brain years after the initial incident.5

      Team leader, Michael Knauth, M.D., Ph.D, said:

      “HACE is a life-threatening condition. It usually happens in a hostile environment where neither help nor proper diagnostic tools are available. It was previously thought that HACE did not leave any traces in the brains of survivors. Our studies show that this is not the case. For several years after, microhemorrhages or microbleeds are visible in the brains of HACE survivors.”


  • High altitude pulmonary Edema (HAPE): fluid builds up in the lungs, preventing oxygen from getting into the bloodstream. As HAPE progresses and blood oxygen levels drop the patient will develop a blue tinge to the skin (cyanosis), breathing will become more difficult, the chest will tighten, there will be a persistent cough with pinkish sputum, the patient will feel very exhausted and weak, and there will be confusion and disorientation. If left untreated death is a likely outcome.

    Also, in cases of HAPE, the patient should be descended by at least 600 meters (2,000 feet) immediately.

    While climbing Mount Kilimanjaro, former tennis champion Martina Navratilova was hospitalized for pulmonary edema, according to an article published in High Altitude Medicine & Biology.6

Both these conditions are uncommon, but may occur if somebody ascends to a very high altitude too rapidly, and stays there.

Prevention of altitude sickness

Climbers should be informed of the risks, symptoms and treatments for altitude sickness. If the ascent is to take place in a remote mountain it is important to be prepared and to take precautions.

  • Acclimatization: the best way to prevent altitude sickness is to ascend gradually so that your body can become acclimatized to the changing altitude. Plan the acclimatization and make sure your trip includes enough time for this. Make sure everyone in the group is fully acclimatized before ascending.
  • Vacation packages: beware of vacation packages that promise to ascend a mountain in just a few days.
  • Fluids: consume between 4 to 6 liters of water per day.
  • Food: eat a high calorie diet while at high altitude.
  • Worsening symptoms: if moderate altitude symptoms worsen you should descend immediately.
  • Sleeping: when your altitude is over 3,000 meters, ascend no more than 300 meters each night. In other words, do not sleep at more than 300 meters higher than you slept the previous night. Even if you ascend more than 300 meters during the day, before going to sleep come back down so that you are no more than 300 meters higher than the night before when you go to sleep.
  • Smoking: do not smoke.
  • Alcohol: do not consume alcoholic drinks.
  • Acetazolamide/Dexamethasone: these medications can also be used to prevent altitude sickness.
  • Moderate symptoms: people with moderate symptoms should stay at their current altitude until their symptoms have gone completely.
  • Other medications: some medications may make symptoms worse while at high altitude, or ascending, including tranquilizers and sleeping pills.


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