Staying safe and healthy when trekking "High Altitude"

High Altitude Trekking

Trekking in the high mountains of Nepal is a unique and rewarding experience. However, it also comes with some risks and challenges, especially when you go above 2,500 meters. One of the most common and serious problems that trekkers face is Acute Mountain Sickness (AMS), also known as altitude sickness. AMS is a condition that occurs when your body does not get enough oxygen at high altitudes. It can affect anyone, regardless of age, fitness, or previous experience. If left untreated, AMS can lead to life-threatening complications such as High Altitude Cerebral Edema (HACE) or High Altitude Pulmonary Edema (HAPE).

Therefore, it is very important that you learn about the symptoms, prevention, and treatment of AMS before you start your trek. Here are some key points to remember:

Symptoms of AMS The symptoms of AMS usually start within 6 to 12 hours after reaching a higher altitude.

They may include:

Loss of appetite
Nausea or vomiting
Fatigue or weakness
Dizziness or lightheadedness
Difficulty sleeping

These symptoms are mild and may go away with rest and acclimatization. However, if they persist or worsen, they may indicate a more severe form of AMS. The signs of severe AMS include:

  • Severe headache that does not respond to painkillers
  • Repeated vomiting
  • Difficulty walking or coordination problems
  • Confusion or altered mental state
  • Extreme fatigue or exhaustion
  • Shortness of breath at rest or with minimal activity

The above signs are a medical emergency and require immediate descent and treatment. They may indicate HACE or HAPE, which can be fatal if not treated promptly.

Prevention of AMS The best way to prevent AMS is to ascend slowly and gradually. This allows your body to adjust to the lower oxygen levels at high altitudes. 

Here are some general guidelines for safe ascent:

  • Do not increase your sleeping altitude by more than 300 to 500 meters per day above 2,500 meters.
  • Take a rest day after every 1,000 meters of altitude gain.
  • Drink plenty of clean water and avoid alcohol and caffeine.
  • Eat a balanced diet with enough carbohydrates and calories.
  • Avoid strenuous exercise or overexertion.
  • Take prophylactic medication such as Acetazolamide (Diamox) if advised by your doctor.

Treatment of AMS 

If you develop any symptoms of AMS, you should stop ascending and take the following steps:

  • Rest and drink fluids (not alcohol).
  • Take painkillers such as ibuprofen or paracetamol for headaches.
  • Take Acetazolamide (Diamox) 250 mg twice a day if you have it or if prescribed by your doctor.
  • Monitor your symptoms and oxygen saturation level if possible.

If your symptoms improve, you can continue your trek at the same altitude or slightly higher. If your symptoms do not improve or get worse, you should descend as soon as possible with a friend or a guide.

Descending is the most effective treatment for AMS and can save your life.

If you have any signs of severe AMS, you should descend immediately and seek medical attention. You may need oxygen therapy, steroids, or other medications to treat HACE or HAPE.

Where to Get Help for AMS? 

If you need medical help for AMS or any other health issues while trekking in Nepal, you can visit one of the aid posts operated by the Himalayan Rescue Association (HRA). The HRA is a voluntary non-profit organization that provides medical services and education to trekkers and mountaineers in Nepal. It was founded in 1973 and has two aid posts along the popular trekking routes: one at Pheriche (4,250 m) on the way to Everest Base Camp and one at Manang (3,550 m) on the Annapurna Circuit. 

Both aid posts are staffed by volunteer doctors from different countries during the spring and autumn seasons.

The HRA also runs Everest ER, a medical clinic at Everest Base Camp (5,350 m), since 2003. Everest ER provides medical care to climbers, support staff, and visitors at the base camp.

You can visit any of these facilities for consultation, treatment, or evacuation if needed. You can also attend daily talks on altitude sickness at 3 pm at the aid posts or the HRA office in Kathmandu during the trekking seasons. 

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