What is Altitude Mountain Sickness (AMS)?

Acute mountain sickness
AMS is a disorder caused by being at high altitude without proper prior acclimatization where there is hypoxia in the air (low oxygen level in the air). Normally, the early symptoms of AMS are seen at altitudes above 8,000 feet (2,500 meters).

The severity of AMS gets more fatal if the trekker continues to gain height, even after the early symptoms are seen. The AMS can progress to High Altitude Pulmonary Edema (HAPE) or High Altitude Cerebral Edema (HACE) which are seriously the life taking altitude sickness, if the immediate action of supplying surplus oxygen or rapid rescue to lower altitudes are not undertaken.

10 Clearly visible or feel able symptoms of AMS

Because of the hypoxia in the air, the blood influences blood vessels to dilate in an attempt to supply more oxygen to the brain and hence the trekkers or climbers begin to show the early symptoms of AMS.

Lack of Appetite and Nausea:
Despite of tremendous physical exercises throughout the day which is very obvious while trekking, the trekkers do not have appetite to eat. Additionally, the feeling to vomit is also the preliminary symptoms of AMS.

Gaining height means getting more into the thinner air. Hence, each breath while inhaling oxygen has lesser molecules of oxygen which results to change of breathing pattern. The breathing pattern becomes faster and deeper than normal so that the body gets enough oxygen. Change in breathing pattern while sleeping causes insomnia which is also a vital early symptom of AMS.

Physical pressure while trekking the long hours followed by Insomnia shows the next symptom of AMS which is fatigue.

A reeling sensation; a feeling of falling down, dizziness is one of the early symptoms of AMS.

Pins and Needles:
The sensationof alimb “falling asleep” is Pins and Needles which is also an early symptom of AMS.

A state where the trekkers feel very sleepy could be one of the symptoms of AMS.

Excessive flatulence:
The disorder in the digestive system, which results to excessive gas in the alimentary canal, is also one of the vital symptoms of AMS.

General Malaise:
Malaise is generally the feeling of being sick and this is one of the first signs of AMS.

Peripheral Edema:
Most of the times because of the accumulation of fluids in the lower limb, the tissues swell which is Peripheral Edema. Peripheral Edema is also one of the symptoms of AMS.

These are the clear symptoms of AMS. However, nose bleeding and rapid pulse rate are also seen as the early symptoms of AMS. Since, AMS feels like a very bad hangover, it is essential to make sure you don’t experience it while on the trekking holiday. If any three symptoms from the above mentioned ten symptoms are seen, it is more likely to declare AMS has affected the trekker. Ignoring the early symptoms of AMS and continuing to gain more height can lead to the severe forms of AMS which could be life threatening.

Life Threatening forms of AMS

High altitude Pulmonary Edema (HAPE)

The filling of fluid in the lungs is Pulmonary Edema. The fluid in the lungs blocks the passage of fresh oxygen to get into the lungs which causes the shortage of oxygen in the lungs. Though the exact reason for the HAPE has not been identified, scientists think that pressure of blood vessel around the lungs is directly proportional to the altitude. As a result the smaller blood vessels leak allowing the fluid to escape to the lungs. HAPE is fatal as its signs are seen few days later after the arrival to the high altitude. HAPE can lead to death or coma if not treated as soon as possible.

Symptoms of HAPE:

Symptoms like of Bronchitis:
The major symptoms of bronchitis like, hacking cough, chest pain, wheeze or breathlessness even while resting and tiredness are the symptoms of HAPE.

Dry cough:
Frequent dry cough producing white or pink sputum.

Chances of getting low grade fever occasionally.

Swelling body parts:
There are possibilities of having swelling ankles or limbs when HAPE strikes.

Alteration of colors:
The color of the body parts like fingernails or lips may turn into blue or grey.

High Altitude Cerebral Edema (HACE)

HACE is the accumulation of fluid in the brain because of the swollen blood vessels to the brain. Unlike to HAPE, HACE is seen within couple of hours and fatal enough to send the patient to coma and take his/her life in just few hours. Though it is still unproven, the excessive flow of blood to the brain because of low level oxygen causes vasodilation which eventually leads to leakage of blood vessels to the brain.

Symptoms of HACE

Headache does not respond to analgesic:
Because of the swollen blood vessels, severe headache continuously strikes which do not respond to analgesics at all.

Nausea and Lethargy:
The increasing rate of nausea will result excessive vomiting as well as extreme weakness because of the deficiency of energy will be observed.

Loss of consciousness and hallucination:
The person developing HACE sees or hear things that which have not happened in reality), feeling puzzled. Person with HACE starts to act absurdly or strangely.

Retinal Hemorrhage:
The retensitive tissue of the eye bleeds, which is also one of the symptoms of HACE.

Sometimes Fits:
Because of the disturbance in electrical activity of the brain the person developing HACE may sometimes gets attacked by Fits.

Risk factors of AMS:
Altitude sickness can’t be predicted. However, certain groups of people are more likely to develop altitude sickness, including people who:

Prior history of AMS:
The person who has been hit by AMS in the past can possibly develop AMS while trekking in the high altitude.

Habitants of below 1000ft:
In the Himalayas the elevation rises rapidly. So, the habitants like of Rome 20m above from the sea level, are not used to with the elevation of the mountains in Nepal which normally lie above 1000m. The persons traveling from such low altitude are more likely to develop AMS while trekking the Himalayan Regions.

Current Respiratory Infection:
AMS develops because of the low oxygen level in the air. The person who has just been through respiratory problems can easily develop AMS while on the mountains.

Rapid Ascent:
This is the most important point; every trekker must strictly follow to avoid AMS. Climb High Sleep Low, is the basic principle of trekking. The trekker who is in a rush and gains the elevation rapidly is more likely to develop AMS.

Exertion beyond the limit in initial two days:
The trek relatively starts softly, and gradually becomes moderately challenging and sometimes becomes extremely challenging. Display of the efforts beyond the necessity in the initial two days without properly acclimatizing makes the trekker stimulant to AMS.

Because of negative pleural pressure needed to initiate airflow, obese person may have reduced respiratory muscle strength resulting difficulty while breathing. So, obese persons have higher chances to develop AMS.

Consumption of Alcohol:
In the initial stage of the trek, alcohol blocks the process of acclimatizing. Therefore, it is recommended not drink alcohol throughout the trek as body needs to be properly acclimatized to the lower oxygen levels of high altitudes. Moreover, altitude sickness is exactly like a bad hangover, so consumption of alcohol may mislead in identifying the symptoms of AMS.

Genetic Composition:
Sometimes, the genetic makeup of your body might also influence AMS while on high altitude.

Counter to AMS, HAPE and HACE

Drink plenty of water:
Drinking plenty of water in the high altitude avoids dehydration as there are chances of losing enough water through perspiration. Keep the electrolyte balance drinking energy drinks and avoiding alcohol and caffeine. Drinking enough water helps in manifesting the clear signs of AMS relatively in shorter time span.

Eye on the AMS Symptoms:
Headache, lack of appetite, nausea, insomnia, fatigue, dizziness, pins and needles, dopiness, excessive flatulence, general malaise and peripheral edema are the clear signs of AMS. Rating one point each to above mentioned signs, if trekker scores 3; there are possibilities that the person is developing AMS.

Climb High Sleep Low:
This is the golden rule of trekking. This is the most essential guideline while trekking above 3000m. Gain as much as altitude you can but, while picking the spot to sleep make sure the place is not more than 400m higher than the place you spent the night the previous day.

Proper Acclimatization:
Acclimatization with the high altitude is what trekkers have to begin from the initial stage of the trek. Climbing higher with frequent rest days is the better way to acclimatize. Rest days, does not mean to chill in the hotel or so. Hiking around to the higher elevation and returning to the hotel or tea house could be best way to acclimatize during the treks in Nepal.

Multiply Acclimatization:
If required use Acetazolamide (Diamox) 125mg twice a day. It enhances breathing, increases blood oxygen level, speeds up acclimatization which could be the best way to get to the desired destination without developing AMS.

Use of analgesic like Brufeen can provide the relief from headache and consumption of 4mg of Dexamethasone four times a day reduces the brain swelling. Though these are not permanent solution to avoid AMS, the person likely to develop AMS can get relief before the further actions are taken.

Carry the life savers:
In the high altitude carrying oxygen or Portable Altitude Chambers (Gamow Bag) is a wise thinking. Gamow bag or Hyperbaric Bag simulates to decrease the altitude by 1000m which could be the life saving tool, while having hard times in the middle of nowhere because of the AMS.

Descend down or Abort the Trek:
Upon developing AMS, it is a wise decision to descend down to the lower altitude. Taking rest for acclimatization before you are fit enough to resume the trek is necessary. If the signs of AMS are still seen the best thing is to abort the trek. Afterall, nothing is more precious than the life itself.

Emergency Rescue:
The severe forms of AMS like HAPE and HACE are life threatening. If the condition of the person developing AMS worsens necessary steps for emergency evacuation and rescue shall be immediately undertaken. Communicating to the host is the best option, who can make quick arrangements for emergency rescue.

In average 10/100000 trekkers in the Himalayas of Nepal lose their lives. Though the number of high altitude victims is low enough to ignore, our attempt to circulate these information is to reduce the causality number to zero. Application of conscience used with proper information can easily save the life in the high altitude.