Altitude sickness is the human body’s reaction to atmospheric pressure and a reduction of the concentration of oxygen present in the air. As you climb higher into the mountains, your body gradually adapts to the reduced amount of oxygen in the air. The appearance of altitude sickness symptoms shows that your body has increased its altitude level faster than it can acclimatize to the corresponding change in atmospheric pressure and reduction in oxygen. In trekking, altitude acclimatization processes are different for each trekker.
Whilst trekking in such places anyone can fall ill with high altitude sickness regardless of their body shape, experience and previous mountain trekking experience. There’s no need to fear high altitude sickness, but it’s very important that you know how to avoid it, how to recognize it and how to act correctly in the event that you encounter symptoms of altitude sickness.
In rare cases, symptoms of altitude sickness may begin to appear starting from 2,400 meters above sea level, but an increased risk of high altitude sickness sets in starting from the 3,500 meter mark. The high risk or mountain zone starts from 5,500 meters.
The primary symptoms of Acute Mountain Sickness (AMS) are:
-Loss of appetite
-Fatigue and weakness
-Shortness of breath
-Swelling of the face and hands.
Mild altitude sickness symptoms are experienced by about up to 20% of trekkers at altitudes of up to 3,000 meters above sea level.
At extreme altitudes, above 4,500 meters, Acute Mountain Sickness can turn into High Altitude Pulmonary Edema (HAPE) or High Altitude Cerebral Edema (HACE) which are both very serious.
High Altitude Pulmonary Edema (HAPE) symptoms include: serious fatigue, shortness of breath and dry cough, shortness of breath at rest, rapid and shallow breath, frothy or pink mucus possible, gurgling, rasping sound when breathing, pressure, heavy feeling in the chest, restlessness, rapid pulse, possible fever, cyanosis – blue or gray lips and indescribable lethargy.
High Altitude Cerebral Edema (HACE) symptoms include: powerful headache which doesn’t pass using painkillers, loss of coordination (ataxia), vomiting, apathy, fatigue, indifference, walks as if drunk, behavioral changes, confusion, hallucinations, cramping fits, short-term blindness and numbness or paralysis of individual body part.
HACE is the most dangerous form of high altitude sickness. It progresses rapidly and requires quick action to prevent the trekker’s death. You may only have a few hours time to successfully implement rescue measures depending on the degree of seriousness of HACE.
Things to Avoid
Respiratory depression (the slowing down of breathing) can be caused by various medications, and may be a problem at altitude. The following medications can do this, and should never be used by someone who has symptoms of altitude illness (these may be safe in persons who are not ill, although this remains controversial)
– Sleeping pills (acetazolamide is the sleeping tablet of choice at altitude)
– Narcotic pain medications in more than modest doses
The key to avoiding AMS is a gradual ascent that gives your body time to acclimatize. People acclimatize at different rates, so no absolute statements are possible, but in general, the following recommendations will keep most people from getting AMS
– walk slow and steady
– Drink plenty of liquid prior to the start and during the hike
– Be honest and tell how you are feeling to the group members and guide.
– Take it easy relax and think positive and enjoy the scenery
– if you hit By AMS head to back lower elevations immediately.
Preventing Severe AMS
This simply cannot be emphasized too much. If you have symptoms of AMS, DO NOT ASCEND ANY HIGHER. Violating this simple rule has resulted in many tragic deaths.
If you ascend with AMS you will get worse, and you might die. This is extremely important – even a day hike to a higher elevation is a great risk. In many cases of High Altitude Cerebral Edema, this rule was violated. Stay at the same altitude (or descend) until your symptoms completely go away. Once your symptoms are completely gone, you have acclimatized and then it is OK to continue ascending. It is always OK to descend, you will get better faster.
The best way to treat altitude sickness symptoms is to descend. With Acute Mountain Sickeness it is best to descend at least 400-500 meters or to the previous altitude at which there were no symptoms. With HAPE and HACE, one should descend immediately at least 500-1,000 meters. Trekkers should rest for a day or two and drink lots of fluids. If sysmptoms have completely disappeared, the trekker can ascend again. If symptoms continue to worsen the victim should continue to descend or be evacuated.
NOTE: In this situation, the affected trekker will need to go down to lower elevation. We will arrange for a guide to accompany the sick person and rest of the members keep continue in their journey.
Pre-Trip and Equipment to standby (by our office). We do not take any chance to rely on our foreign operators to provide equipment.
1. All climbers are advised to see a local doctor prior to the trip to seek medical advice and obtain prescribed meds for AMS treatment. This will be enforced if we are trekking above 3,500m at any point of the journey.
It is important that you inform your trek leader of any medical conditions or medications before ascending to altitude.
2. Travel Insurance is compulsory (in case of a heli-evac, participant can claim the cost from insurance company and need not bear the entire cost)
3. Oxgen bottles
In case of an emergency, O2 will be provided. The cost of usage are claimable with your insurance company.
4. Blood Pressure Machine (Why do we need it?)
If the blood pressure is too low the patient may not receive adequate blood flow to the brain and heart and could die within minutes.
If the blood pressure is too high the patient will become unstable and may experience heart failure or stroke.
We monitor the blood pressure frequently because small changes in the pressure readings over a period of time can give us clues about the cardiovascular and respiratory health of the patient. We can be guided by changes in the pressure readings to add or remove certain medications from the patient’s treatment regimen.
3. Pulse oximetry – compulsory readings daily (Why do we need it?)
Pulse oximetry is a test used to measure the oxygen level (oxygen saturation) of the blood.
It may be used:
- To see how well lung medicines are working
- To check a person’s ability to handle increased activity levels
- To see if a ventilator is needed to help with breathing, or to see how well it’s working
- To check a person has moments when breathing stops during sleep (sleep apnea)
4. Diamox and other basic medicine
5. Walkie Talkie
1 for Event host and 1 for co-host (if any)
1 for the group leader, 1 for leading guide and one for the assistant guide – (Nepal)
Your trek leader reserves the right to make the decision that you or a member of your group is at risk of serious altitude sickness and for safety insists that you cannot ascend further – please respect that they are within their rights to do so and are making that decision in the best interests of your health and well-being.
Any calls for evacuation must first be approved by the trek leader.