Edema of the lungs (associated with high altitude)
High Altitude Pulmonary Edema
What is altitude sickness? — Traveling to high altitudes can sometimes cause health problems (figure 1). This group of problems is called "altitude sickness." This can happen if you go to the mountains, or just visit cities that are at high altitude (for example, Mexico City or Denver, Colorado).
The 3 main types of altitude sickness are:
Acute mountain sickness – This is the most common type and causes symptoms like those caused by an alcohol hangover.
High altitude cerebral edema (also called "HACE") – This is less common but more serious than acute mountain sickness. It involves swelling of the brain.
High altitude pulmonary edema (also called "HAPE") – This is also less common and more serious than acute mountain sickness. It involves fluid buildup in the lungs.
If you are planning to go somewhere at high altitude, there are things you can do to keep from getting altitude sickness.
What are the symptoms of altitude sickness? — The symptoms differ depending on the type of altitude sickness you have.
Acute mountain sickness can happen within a day of traveling or climbing to a very high altitude. The symptoms can include:
Having no appetite
Nausea, sometimes with vomiting
Getting short of breath with exercise
If you have these symptoms, do not travel or climb any higher until you feel better. You should feel better within a day or so.
The symptoms of HACE (swelling of the brain) usually start 1 to 3 days after traveling or climbing to at a high altitude. They include:
Extreme tiredness and weakness
Trouble walking normally
Confusion and irritability
The symptoms of HAPE (fluid in the lungs) usually start 2 to 4 days after traveling or climbing to a high altitude. They include:
Trouble walking uphill
Is there anything I can do on my own to feel better? — Yes. If you have mild symptoms of acute mountain sickness, you should rest. Do not travel or climb to a higher altitude until you feel better. Moving to a lower altitude can also help, if symptoms do not go away in a day or 2. For a headache, you can take medicines such as aspirin, acetaminophen (sample brand name: Tylenol), or ibuprofen (sample brand names: Advil, Motrin).
You might be tempted to keep climbing, especially if you are with other people. But it's important to rest so you don't get worse. If you are climbing or traveling with someone who has symptoms of altitude sickness, stay with them so you can get help if needed.
If you have symptoms of a more serious problem, such as HACE or HAPE, try to get help right away and move to a lower altitude immediately.
Should I see a doctor or nurse? — If you have severe symptoms after traveling or climbing to a high altitude, get medical care right away. Waiting to get treatment could cause serious health problems, or even death.
How is altitude sickness treated? — Treatment depends on which type of altitude sickness you have. If you have symptoms of acute mountain sickness, rest and stay where you are until you feel better. If your symptoms get worse, move to a lower altitude.
There are also prescription medicines that can help treat the symptoms of acute mountain sickness. These include:
Acetazolamide (brand name: Diamox) – This medicine can help prevent and treat acute mountain sickness.
Dexamethasone (brand name: Decadron) – This medicine can help keep the symptoms of acute mountain sickness from getting worse. It can also help prevent or treat swelling of the brain.
The most important treatment for HACE (swelling of the brain) or HAPE (fluid in the lungs) is to get to a lower altitude right away. If you have HACE or HAPE and cannot get to a lower altitude, you might be put inside a special inflatable bag called a "portable hyperbaric chamber" (picture 1). Once you are zipped inside this bag, it is filled up with air that is similar to the air at lower altitudes. You might also get extra oxygen to breathe.
Can altitude sickness be prevented? — Yes. The best way to prevent altitude sickness is to avoid moving quickly to a higher altitude. Going slowly gives your body time to adjust.
If you are traveling to a very high altitude, plan to stretch your trip out over several days.
If you are hiking or climbing, don't do difficult physical activities for the first few days, and avoid alcohol and sleeping pills.
When hiking, go to a higher altitude during the day and then go back down to a slightly lower altitude each night to sleep.
If you have had altitude sickness before, your doctor might give you a medicine to keep you from getting it again.
All topics are updated as new evidence becomes available and our peer review process is complete.
This topic retrieved from UpToDate on: Mar 30, 2020.
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