The next day you scope out the peak and stash gear at 16,500 feet. A nagging headache makes dinner unappealing. You spend the night tossing and turning, and the next day you admit to the others (who just arrived) that you’re “not feeling great.” On day three, you lie in your sleeping bag as the team does a light hike. You try carrying a load the next day, but nausea and dizziness force you back. On day five, you’re having trouble standing straight and your cook carries you down to safety. A few days later, the team prepares for their summit push. They will be summiting right as you are arriving back at basecamp.
The above is a lesson in patience—and acclimatization. This process takes time. Fitness, age, and experience make no difference. Hazards from not acclimatizing properly are illness or death. This process of physiological adjustment to the low oxygen content at high altitude differs from person to person. For you, the climber, acclimatization means matching how fast you go up with how fast your body adjusts. There are no hard-and-fast rules with acclimatization, but here are some tips on how to best approach the “climb high, sleep low” guiding principle of acclimatizing. Remember, this information is no substitute for professional care and training. A Wilderness First Aid class is a great way to learn about the hazards of Altitude Sickness.
Altitude sickness is the general term for what happens when you aren’t acclimatized. Symptoms can range from a mild headache to incapacitation and death. Altitude sickness comes in three forms: Acute Mountain Sickness (AMS), High-Altitude Pulmonary Edema (HAPE), and High-Altitude Cerebral Edema (HACE). Any of these three illnesses can strike a highly trained athlete, a veteran mountaineer, or a couch potato with little regard for their lifestyle. Altitude sickness can occur while stepping on the summit of K2 at 28,251 feet or stepping off a plane in Denver at 5,430 feet. No one has immunity from it, people who have never gotten it before can get it unexpectedly.
Altitude sickness is an equal opportunity oppressor. Expedition skier Luke Smithwick says, “No one should take it personally. Some of the best climbers on earth, people who plan to do all fourteen 8,000-meter peaks with no oxygen can take weeks to acclimatize.” It can strike in a few hours. The only cure is to decrease elevation. There are several factors that affect acclimatization—fitness, other illness, level of hydration, what altitude you live at, how much you push yourself physically, and new studies indicate that genetics might play a role in it.
As with other aspects of expedition climbing, consult professionals prior to departure. Your travel doctor will provide information, guidelines for treatment, and necessary medications. Once again, experience is the best teacher. Err on the side of safety.
There are several ways climbers successfully “pre-acclimatize.” One is to visit and sleep above 10,000 feet prior to your expedition. This is only possible in certain regions, and costs time and money. An alternative process involves sleeping at progressively higher altitudes in your home through the use of a hypobaric chamber set up around your bed. This is an expensive strategy generally used by those who have more money than time. See Hypoxico
A word of caution. Expert big mountain climber and guide Garrett Madison says, “This works over time to build more red blood cells, but the tent can’t mimic the pressure at altitude. I think it’s best to take it easy even if using the tent to cut out part of an expedition. However, it does work. I regularly have climbers who sign up for my ‘Everest Express’ program, where they climb the peak with me in less than a month, rather than the more traditional two-month program.”
TREATMENT: If one rests and proceeds no higher, AMS usually resolves itself in two days. The following steps help:
SYMPTOMS: HAPE shows up as shortness of breath accompanied by a cough. It may or may not initially appear as AMS. This condition may emerge from untreated AMS. It can creep up in mere hours. Symptoms include progressive shortness of breath, unusual fatigue and exhaustion following exertion, and wet coughing, often productive (meaning it produces sputum when you cough).
TREATMENT: HAPE is a very serious and potentially fatal condition that can be treated with supplemental oxygen and rest. While resting at the same altitude sometimes works, descending 1,000 feet or more may be necessary. If available and descent is not possible, a hyperbaric, inflatable pressurized bag (Gamow®) might be necessary.
SYMPTOMS: The telltale symptom of HACE is ataxia, or impaired balance. HACE starts with AMS-like symptoms and progresses through severe headache, confusion, lethargy, lack of coordination, irritability, vomiting, seizures, coma, and eventually death if untreated. This condition might emerge over days, or may strike in hours. The signs are inability to walk a straight line, going heel to toe, or the inability to balance on one foot.
TREATMENT: HACE is a very serious and potentially fatal condition. The victim needs to immediately descend to lower altitude. Descent must be followed by professional medical treatment. A person with HACE must be taken to a lower altitude. Canned oxygen therapy should be started if available, and dexamethasone, a steroid medication in pill form, should be given immediately. If the hyperbaric bag (Gamow®) is available, use it right away.