Acute Mountain Sickness

What is Altitude Sickness?

Altitude sickness also known as Acute Mountain Sickness ( AMS) occurs when a person travels to a high altitude above 8,000 feet/2500 m,  without gradually acclimatizing. Acute Mountain Sickness occurs from lack of oxygen.

What are the Symptons for Acute Mountain Sickness?

Symptons Include

• Headache is the Primary symptom,
• Weakness,
• Loss of appetite,
• Nausea,
• Vomitting
• Weakness,
• Insomnia,
• Dizziness,
• Feeling sleepy,
• Swelling of hands, feet and face,
• Shortness of breath

If not taken care of immediately Acute Mountain Sickness  can lead to life-threatening complications. A person who is not used to high altitudes is most at risk of developing altitude sickness.

What are the causes for AMS?

The leading cause of altitude sickness is ascending to a great height too rapidly. Staying at high altitudes for extended periods may also cause forms of altitude sickness.

At sea level, the oxygen concentration in the air is approximately 21%, and air pressure averages 760 millimeters of mercury (mm Hg).

At higher altitudes, the oxygen concentration remains the same, but air pressure is much lower. For example, at the peak of Mount Everest, air pressure is around 228 mm Hg. Lower pressure means that the air is less dense, and therefore the number of oxygen molecules per breath is reduced.

At around 18,000 ft, each breath contains approximately half of the oxygen found at sea level.

If a person has less oxygen in their blood, their heart and lungs have to work harder. This raises their pulse and their breathing rate. In response, the body creates more red blood cells to carry more oxygen. However, even though breathing faster increases blood oxygen levels, they do not reach sea level concentrations.

The average human body needs from 1 to 3 days to become acclimatized to a change in altitude. People who do not spend enough time acclimatizing to a new altitude before progressing further have the highest risk of developing altitude sickness.

The body may also respond to a change in altitude by altering blood acidity level, lung pressure, electrolyte levels, and fluid and salt balance. Rising to higher altitudes can also cause fluid to leak from tiny blood vessels, resulting in a potentially dangerous fluid buildup in the lungs and the brain.

Types of Altitude Sickness?

• Chronic mountain sickness develops after a person spends an extended time living at high altitudes.
• Acute altitude sickness occurs in a much shorter time frame. A person may experience acute altitude sickness at any point 1 to 5 days after ascending above 8,000 ft. Acute altitude sickness may develop into more severe conditions, including High-Altitude Cerebral Edema and High-Altitude Pulmonary Edema also known in short as HAPE.

What is High-Altitude Cerebral Edema and High-Altitude Pulmonary Edema?

High-Altitude Cerebral Edema (HACE):

This is the swelling of the Brain. Lack of oxygen at high altitude combined with the subsequent changes in pressure within the blood vessels causes fluid to leak through tiny blood vessels into the brain. This leads to swelling of the brain. High-Altitude Cerebral Edema occurs when a person stays at a high altitude for at least 1 week. If  left untreated, there is a very high risk of death. A person presenting symptoms of HACE should descend immediately.

High Altitude Pulmonary Edema(HAPE):

High Altitude Pulmonary Edema causes fluid to build up in the lungs, preventing oxygen from getting into the bloodstream. As this progresses and blood oxygen levels drop, several symptoms may develop, including:

• Persistent Coughing
• Blue Tinge to the Skin
• Fever
• Panting or running out of breath even while resting
• Signs of swelling of the brain include:
• Persistent headache that does not respond to painkillers
• Unsteady Gait or Clumsiness
• Increased vomiting
• Changes in consciousness
• Numbness
• Dizziness

Treatment for Acute Mountain Sickness(AMS)

• A person who develops symptoms for AMS should immediately stop ascending and rest until their symptoms have cleared. But it is best to descend to a lower altitude immediately. Moving to a lower altitude is usually the best action to take if a person develops symptoms of altitude sickness. Once acclimatized they may be able to ascend once more.
• Those who are experiencing very mild symptoms of Acute Mountain Sickness may continue ascending but at a much slower pace.
• Those with more severe symptoms should rest, consume plenty of fluids, and avoid smoking and drinking Alcohol as that may affect blood oxygen levels.
• There are a number of potential treatments that may remedy altitude sickness. These include:
• Giving pure oxygen can help a person with severe breathing problems caused by altitude sickness.
• A Gamow bag: This portable, plastic hyperbaric chamber can be inflated with a foot pump and is used when a rapid descent is not possible.
• Painkillers:Acetaminophens, such as Tylenol, can be taken for headaches. Ibuprofen an anti-inflammatory medicine, can also help.
• Acetazolamide: This can check the chemical imbalance in the blood caused by altitude sickness and speeds up a person’s breathing rate. However, this medication may cause some side effects, including a pins and needles feeling in the face, fingers, and toes, excessive urination, and blurred vision in rare cases. However, an experienced medical Practioner should be consulted before It’s use.
• Dexamethasone: This is a steroid hormone that can suppress immune activity and inflammation. This medicine can reduce the incidence of Acute Mountain Sickness and other complications. However, the medication has some possible side effects, like stomach pain, depression and euphoria.
• Nifedipine: Doctors commonly prescribe this medicine to treat high Blood Pressure. It is effective for treating fluid buildup in the lungs. This medication reduces the narrowing of the pulmonary artery, easing chest tightness and making breathing easier.

Prevention for Altitude Sickness

1. The best possible solution to prevent Altitude sickness is by ascending gently, thus allowing time for gradual acclimatization of your body to the gain in altitude. However, a person may be able to take other precautions too.
2. Intake of Fluids: A hiker should increase his/her fluid intake when ascending to high altitudes.
3. Food: When climbing at high altitudes, a person may benefit from consuming a high-calorie diet.
4. Sleeping: People should not increase their sleep elevation by more than 985-1,970 ft per night when climbing over several days.
5. Resting: Every 3-4 days of climbing, people should rest every for one full day to allow the body to acclimatize.
6. Smoking: A person should not smoke before or during a climb.
7. Alcohol: Before ascending to high altitudes, a person should avoid alcohol.
8. Acetazolamide and dexamethasone: A person can use these medications to prevent altitude sickness. However, their use is not common practice outside of advanced athletes, such as experienced climbers, since these medications have multiple side effects.

To Summarize in Short:

Altitude sickness occurs when a person rapidly ascends to high altitudes, normally above 8,000 ft. Symptoms of altitude sickness can include headaches, dizziness, and shortness of breath. If a person stays at high altitudes for an extended period, they may develop chronic altitude sickness. If they do not get medical help, this can lead to potentially fatal complications. A person can prevent altitude sickness by ascending gradually and allowing the body to acclimatize to new heights. A doctor may prescribe several different medications to treat altitude sickness, or in some cases, recommend oxygen supplementation. However, a person may remedy altitude sickness symptoms most effectively by descending to lower altitudes.