Altitude sickness develops when the rate of ascent into higher altitudes outpaces the body’s ability to adjust to those altitudes. Acclimatization is critical for anyone climbing above 8,000 feet but those doing only a two day climb typically don’t have enough time to gradually work their way up the mountain to higher and higher altitudes to adjust. This could make them vulnerable to acute mountain sickness (AMS) which may develop at altitudes as low as 6500 feet.
Physiologically as you ascend higher into the atmosphere there is lower atmospheric air pressure pushing the air molecules together, so oxygen molecules become few and far between. The available amount of oxygen to sustain mental alertness and exercise performance decreases with altitude. Since the number of molecules (of both oxygen and nitrogen) per given volume, drops as altitude increases, you have to move larger volumes of air to get sufficient amounts.
Symptoms of mild to moderate acute mountain sickness may include headache plus at least one of the following:
- Sleep disturbance
- Dizziness or light-headedness
- Nausea or vomiting
- Rapid pulse (heart rate)
- Shortness of breath with exertion
- GI symptoms (loss of appetite, nausea, vomiting),
Prevention of altitude illnesses will increase your chances of enjoying your experience. These tips may help reduce your susceptibility to the effects of being at altitude:
If possible, spend a night at an intermediate altitude before coming to above 9000 feet to sleep.
Your symptoms will depend on how hard you exert yourself. So prepare yourself well by following a mountaineering training program for 6 months before your climb.
Your goal is to be in the best possible physical condition you can. Although physical fitness enables greater exertion at altitude, it does not protect against any form of altitude disease.
Don’t over pack your backpack. Plan very well so that you have what you need but nothing redundant or extraneous. Extra weight means you will have to exert yourself more.
The week before your climb, take extra good care of yourself by eating well, hydrating with at least half your body weight in ounces of water and getting extra sleep. Don’t drink alcohol the week before.
Ascend slowly. Utilize the rest step which preserves energy while helping you maintain a steady pace.
Limit strenuous activity on the first day at altitude.
One of the goals of acclimatization is to increase ventilation (breathing) to compensate for lower oxygen volume in the air. Take slow deliberate deep breaths, use pressure breathing techniques. During your rest step, exhale forcefully through pursed lips, emptying your lungs in one big “whoosh” as if you were trying to blow out a giant candle.
Synchronize your breathing with each movement. Inhale deeply as you step up; exhale fully into the rest step.
Drink an extra liter to liter and a half of water when coming to altitude.
Avoid tobacco, alcohol and other depressant drugs including, barbiturates, tranquillizers, sleeping pills and opiates.
Your guides are experienced in identifying altitude sickness and knowing what to do so let them know how you are feeling.
If you begin to show symptoms of moderate altitude sickness, don’t go higher until symptoms decrease. If symptoms increase, descend.
Eat enough food and drink enough water while on your climb. It is recommended that you drink from four to five liters of fluid per day. Also, eat a high calorie diet (> 70% of your calories) while at altitude, even if your appetite is reduced. Take a variety of your favorite foods that will be appealing to you. Do a trial run of these foods in the month before your big climb so you know if these foods work well for you.
Hydration is critical. Breathing large volumes of dry air at altitude increases water loss. Drinking four to five liters of water a day is usually good but keep an eye on your urine; make sure your urine is clear and copious. If you routinely take a diuretic, tell your doctor you are doing a climb and see if they want you to continue or if you can discontinue for a few days.
Keep your temperature regulated. Wearing warm clothes is important as it allows you to conserve energy that would otherwise be spent on maintaining your body temperature. But don’t allow yourself to get too warm. Learn how to properly layer your clothes so they wick moisture away from you.
Acetazolamide (Diamox) is a medication sometimes used to speed acclimatization. Talk with your mountain guide service ahead of time and your doctor to see if Acetazolamide prophylaxis is right for you. Consider medical prophylaxis if you have had a history of prior AMS.
There is no reliable scientific evidence for Gingko Biloba at this time but some believe that 100 mg by mouth twice daily started 3-5 days prior to ascent then continued for 2-3 days at maximum sleeping altitude is beneficial. If you decide to try it, do a trial run first a month before to make sure you react okay with it. And always inform your doctor or pharmacist if you are taking other medications to avoid a drug interaction.
Treatment of mild AMS: Tylenol 650 mg to 1 gm by mouth every 6 hours as needed until symptoms improve or Motrin 400-600 mg by mouth every 6 hours as needed until symptoms improve.
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