T. Today I’m talking about a term we all know – altitude sickness.
Before reading this, I hope that you have read my previous article on how altitude affects your body. If you haven’t, read it now. It is important that you know some background information first. Find it here if you missed it.
Now let’s start.
What is altitude sickness?
Interestingly, “altitude sickness” doesn’t mean much in itself.
It’s a collective term for different types of illness – it can be as simple as a slight swelling of your fingers to such an excessive build-up of fluid in your brain.
In the most rudimentary sense of the term, “altitude sickness” means that your body does not adapt well to altitude.
With that in mind, today I’m going to talk about the most common forms of altitude sickness that we see on our hikes – AMS, HAPE, and HACE.
Let’s start with the mildest form and move on to the more vicious forms.
1) what is acute mountain sickness (AMS)
AMS is very common when you are hiking in the Himalayas.
How common is it?
Well, in a team of 20, we see at least 3-4 people showing symptoms of AMS. Most of them recover within a few hours.
We also found that not all of them show symptoms at the same time. Some of them may show symptoms in a lower tier, others in a medium tier, and others in a higher tier.
Some also show symptoms when descending!
You might be surprised.
But you should be aware of that. AMS doesn’t always affect you as you progress. It could have hit you at your previous campsite or at the highest point of your hike, and symptoms can appear the next day as you dismount.
So you always have to be vigilant. There is no way out.
When I get to the symptoms, I’ll tell you what we see most often.
Most of the trekkers affected by AMS are shown gastrointestinal symptoms. You either go to the bathroom very often or feel nauseous. Sometimes you vomit. Especially late at night or after going to bed.
In our experience, gastrointestinal (gastrointestinal) symptoms (GI) are much more common than the notorious headache that all manuals tell you about.
Nevertheless, we saw hikers who suffer from it persistent headache also. It builds up while trekking. It lasts all afternoon and evening. Most mistake it for dehydration. Or they assume it’s the heat. Most of the time they are right, but they can also be very wrong.
she I find it hard to sleep at night.
You will often hear her say, “I am uncomfortable.” she I won’t be able to explain this discomfort.
These are all classic symptoms of AMS.
There are more symptoms – Fatigue, loss of appetite, dizziness.
Of the three, keep an eye out for trekkers who charge up on day one and suddenly lag behind on day two. (They will most likely tell you they are slow because they are taking in the scenery. Most of them do not admit symptoms.)
Pay special attention to don’t want to eat.
This infographic shows the possible symptoms of acute mountain sickness. Pay attention to these when trekking.
What I have learned is that at high altitude, any symptom you have must be attributed to AMS first and then to something else.
If these symptoms are treated promptly, AMS can be cured and the trekker can move forward. Most of our trekkers with mild AMS complete the trek after taking medication.
If left untreated and ignored, mild AMS could transform into its sinister cousins - HAPE or HACE.
2) What is high altitude pulmonary edema (HAPE)?
Lungs -> In relation to the lungs
edema -> An abnormal build-up of fluid in parts of the body
HAPE is an advanced form of AMS. And a more dangerous form.
I really wouldn’t want you or anyone to get HAPE. This is when things start to get nasty. It takes a very skilled hand to get you out of this mess.
I say this because HAPE can and will be fatal very quickly. I’m not trying to scare you. These are things that happen at high altitudes.
What actually happens
When a trekker has HAPE, fluid from their blood leaks into air sacs in their lungs (due to the high pressure in the arteries in their lungs).
Simply put, HAPE is like death by drowning. The trekker’s lungs drown in his own body fluids.
And if his lungs are down, you can imagine what could happen. The rest of his body will soon stop working.
Symptoms of HAPE begin with, similar to symptoms of AMS Tiredness, loss of appetite, and difficulty breathing.
But HAPE could suddenly appear without AMS being in front of it. It is quite normal for HAPE to climb a trekker within a few hours – we notice it worsen at night when the trekker is asleep and his breathing becomes shallow. So sleeping at high altitudes with a mild HAPE is a big NO.
To do this, it is very important to identify the symptoms. And the symptoms of HAPE are pretty obvious.
Here’s what we see on hikes.
The trekker affected by HAPE is absolutely exhausted. He has a hard time even going to the toilet tent. His Breathing is difficult, even on gentle walks. An experienced trekker can hear him breathing heavily even when he is sitting.
He coughs quite a bit. A dry type of cough. Not often, but obviously enough.
And here is the final, sure-fire proof: when you rest your head on his chest, you will listen rattling, gurgling sound. You don’t need a stethoscope. All you have to do is hold your head near his chest.
As scary as it sounds, there’s light at the end of the tunnel – HAPE isn’t too regular. And it can be treated.
At Indiahikes we only saw 12 cases of HAPE on our hikes from January 2017 to April 2018. Everyone was brought to safety.
The key is to identify symptoms as early as possible and act quickly.
It is similar with HACE. Let’s talk about this next.
3) What is elevated cerebral edema (HACE)?
Cerebral -> Related to the brain
edema -> An abnormal build-up of fluid in parts of the body
HACE is as serious as HAPE because altitude is now playing with your nerve center.
When a trekker is affected by HACE, their brains swell. This happens because the blood vessels in the brain expand and fill the brain with fluids.
Because HACE affects the brain, the symptoms are clear to see.
Headaches are almost universal among trekkers with HACE headaches that doesn’t work with medication.
Affected hikers act a little strange – they usually speaking excitedly or showing irritation. Their behavior is quite irrational at times. A trekker we know asked for a helicopter to evacuate them. That sounds rational, but if you knew the trekker’s normal behavior, she would never say such a thing.
You sometimes go woozy, like sloshing around after a night of drinking.
This is called medical ataxiawhere the brain tells the body one thing but the body does something else. It is a fundamental loss of muscle coordination.
These are very typical symptoms of HACE.
You can see them too Difficulty speaking, hallucinating, unable to see clearly.
Do not ask a HACE affected trekker to do simple calculations like 5 + 3. They are affected by HACE, but they are not idiots. You will get it right, but you can still be affected by HACE.
A trekker hit by HACE deteriorates within a few hours and could fall into a coma.
So it’s important to act before things get serious.
Fortunately, HACE is very, very rare. From January 2017 to April 2018, we only saw two cases of HACE. We have documented one of them in detail here.
What you need to know about altitude sickness
Altitude sickness is highly dependent on how quickly you gain altitude, your physiology, and the capabilities of your body at the time of your hike.
Altitude sickness is NOT related to your previous experience at high altitude, your fitness preparation, or the food you eat.
However, we have found that those who are better prepared for the hike are less affected. Your lungs are ready to work harder despite less oxygen.
When Sandhya UC suffered from altitude sickness
Our co-founder Sandhya – a fit, experienced and healthy eater – suffered from a bad case of altitude sickness in the form of AMS on the Buran Ghati trek at a relatively low altitude. Fortunately, she knew about the symptoms and medication and was able to escape the clutches of AMS. Read about her AMS experience here. There is a lot to learn from her.
I’m trying to say that anyone can be affected. And everyone can save themselves or others. All it takes is knowledge.
In my next post I will explain how to treat acute mountain sickness, HAPE and HACE. After that, I will also tell you how to prevent it.
I recommend sharing this content with your fellow trekkers. Considering it is May and the next two months will be high altitude hiking season, this will help anyone climbing to great heights.
Hope you found this post helpful.
After reading this, check out our next post on treating acute mountain sickness, high altitude pulmonary edema, and high altitude cerebral edema.
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