Altitude Sickness (AMS)

When a person ascends to a higher altitude, the air pressure in the atmosphere drops and it leads to difficulty in breathing even though the oxygen composition remains the same, this has a physical and mental effect on the human body, it generally affects high altitude trekkers, Skiers, Mountaineers or people travelling on high altitudes, it usually occurs above 8000ft. or 2400 meters, Symptoms starts with a headache, fatigue, stomach illness, dizziness or lightheadedness, loss of appetite, nausea or vomiting, rapid pulse, and difficulty in sleeping, the symptoms depend on a lot of factors like the speed of the ascent and how hard you exert yourself or climbing above 500 meters in a single day, the symptoms are acute to life-threatening,  if not treated early and the person continues to ascend further it may lead to a fatal form of altitude sickness called HAPE and HACE.

HAPE (High Altitude Pulmonary edema): It is a state where the fluid is accumulated in the lungs, it is one of the major causes of death in high altitude, it is important that you recognize the symptoms, like difficulty in breathing while at rest, cough, weakness, congestion. When you recognize two of these symptoms do not waste any time, immediate descent is your best option though some first aid measures are commonly used like administration albuterol, PAC bags or Altitude oxygen cylinders give more time.

HACE (High altitude cerebral edema): It is a state where the brain swells with fluid, it appears in people having AMS, and the symptoms of HACE are a severe headache, confusion, lethargy, seizures, Fever, Hallucinations. If the person is suffering from HACE, it is again important to descent immediately, some common first aid measures used are administering Dexamethasone and also the use of PAC bag or oxygen cylinders which again give you some time.

There are few preventive measures that one can take while on their pursuits to high altitude, the human body has good ability to acclimatize but needs time.

• Ascend slowly as the body needs time to acclimatize to the conditions around.
• Do not climb more than 400 meters per day.
• Rest days should be included in-between, tight schedules are dangerous.
• Drink sufficient fluids and eat well, your body would require more carbs.
• Avoid consuming Diamox. People suffering from high blood pressure or sulfur allergies this could turn out worse.
• Do not consume alcohol and avoid smoking.
• Always sleep at lower altitude, like the climber’s quote “climb high, sleep low”.

 

However, if you have any of the symptoms and would like to know if you have mild or severe AMS you can use the Lake Louis scoring system to diagnose AMS.

 

Symptom Severity Score A headache No headache Mild headache Moderate headache A severe headache 0 1 2 3 Gut (gastrointestinal) symptoms None Poor appetite or nausea Moderate nausea and/or vomiting Severe nausea and/or vomiting 0 1 2 3 Fatigue and/or weakness Not tired or weak Mild fatigue/weakness Moderate fatigue/weakness Severe fatigue/weakness 0 1 2 3 Dizziness/light-headedness Not dizzy Mild dizziness Moderate dizziness Severe dizziness 0 1 2 3 Difficulty sleeping Slept as well as usual Did not sleep as well as usual Woke many times, poor sleep Could not sleep at all 0 1 2 3

 

Total score of:

3 to 5 = mild AMS

6 or more = severe AMS.

Note:

• Do not ascend with symptoms of AMS.
• Descend if symptoms are getting worse.