Kilimanjaro. Alex Stewart
and continues to deliver the necessary amount of oxygen to the blood cells. Most people have the ability to adapt to altitude, if they expose themselves to it sufficiently slowly. However, acclimatization takes different lengths of times for each individual and there is no hard or fast rule as to how long it ought to take to ascend a mountain. It is impossible to predict who will suffer from AMS. Neither youthfulness or physical fitness are guarantees that you won’t be affected. In fact, those young trekkers who forge ahead are the most likely to succumb to the debilitating effects of altitude. Generally though, effective acclimatization to any given altitude takes about a week while full acclimatization can take up to six weeks.
Another vital consideration is water intake. When climbing at altitude, you must consume three to four litres of water per day in order to avoid dehydration. A lot of moisture is lost as you breathe or sweat during the climb. Thirst is not a reliable indicator that you are suffering from dehydration. Instead, look out for signs that include peeing infrequently, in small amounts and the urine being darker and stronger smelling.
A failure to allow sufficient time to acclimatise is almost certain to bring on AMS. The best way to avoid it is to ascend slowly. In this respect, the Kilimanjaro mantra, ‘pole, pole’ meaning ‘slowly, slowly’, is wholly appropriate and accurate. However, there is no optimum period for acclimatisation. A conservative recommendation for climbing high is that above 3200m (10,000ft) you should ideally only increase the sleeping altitude by around 350m (1200ft) per day. It is also recommended that while ascending you take a break every two or three days by sleeping at the same altitude as the previous day. To maximise the benefit of this, you should climb higher during the day, exposing your body to greater altitude, before returning to sleep at the lower elevation. In this way, an ideal ascent of Kilimanjaro should take seven to 10 days to acclimatise properly.
Most ascent routes on Kilimanjaro give you a fraction of that time to reach the top. The ascent is generally far too rapid and side effects of this are inevitable. The summit bid on the standard Marangu Route begins after three days. This is almost three times as fast as the recommendation.
At altitude, it is best to assume that any illness is AMS, until proven otherwise. Early indicators that something is amiss include extreme fatigue, persistent headache, dizziness, a loss of appetite and disturbed sleep caused by irregular breathing. In its mildest form it feels akin to a hangover. A tendency to run out of breath after minimal exertion is also an indication. If any of these symptoms become apparent, the trekker should pause until they have passed. As long as the symptoms remain mild, ascent at a modest rate can continue. If they persist after a day or two, descent to a lower elevation should be strongly considered. If possible, strong painkillers should be avoided as they will mask these early symptoms meaning a potentially serious problem could pass unnoticed.
If the condition continues to deteriorate, the casualty will become even more lethargic, confused, disorientated and out of breath. They may have wet, bubbly breath. The headache will become severe and they may start to cough harshly, sometimes producing pinkish or rust coloured sputum. They may vomit as well. They will also suffer a loss of co-ordination, known as ataxia, and will be unable to walk in a straight line or complete simple tasks. At this stage, the victim is enduring the onset of either pulmonary or cerebral oedema, both of which can result in unconsciousness and death within 12 hours. AMS has been fatal as low as 3000m (9850ft), but most commonly occurs above 3500m (11500ft).
To camp in the crater adjacent to the Furtwangler Glacier (Summit Route) you must ascend slowly and steadily and acclimatise properly
High Altitude Cerebral Edema (HACE)
HACE is a very severe condition. The brain swells and ceases to function properly. This can result in death very quickly. The hallmark of HACE is a change in the ability of the victim to think. They may become confused, disorientated or very lethargic. There is a characteristic loss of co-ordination, called ataxia, that most often manifests itself as a staggering walk. If the victim can’t walk in a straight line, even when not carrying a pack and on level ground, they should be presumed to have HACE.
The treatment is to descend immediately, even if that means doing so in the dark. Delay, even until the following morning, could be fatal. The casualty should be accompanied down at least as far as the last elevation at which they felt no symptoms of the condition. If uncertain, dropping 1000m is a good start. People with HACE usually survive if they descend sufficiently quickly and often recover completely.
High Altitude Pulmonary Edema (HAPE)
HAPE, another form of severe altitude sickness, is caused by a build up of fluid in the lungs. In addition to the usual symptoms of AMS, the victim may make a gurgling or rattling breathing sound. They may also feel a tightness around their chest. HAPE frequently occurs at night and may worsen with exertion. It is also common for HAPE to develop into HACE due to the extremely low levels of oxygen in the victim’s blood.
The treatment for HAPE is the same as for AMS and HACE. Immediate descent to a lower altitude is the optimal solution – even a descent of 500m and the associated increase in oxygen content of the air is often sufficient to reduce the symptoms to a manageable level. People suffering from serious altitude illness should be accompanied off the mountain – at no time should they be allowed to set off on their own. HAPE resolves itself rapidly upon descent and a couple of days’ rest at a lower elevation should ensure a complete recovery.
Trekkers on the Marangu Route often spend an extra day at Horombo Huts to aid acclimatisation and reduce the risk of AMS (Kibo in background)
If, when on your trek, you or a companion begins to suffer HAPE symptoms, it is important to descend at once. If the casualty improves sufficiently, they may be able to continue. However, more than likely, once the descent has begun, the affected person will not be allowed to continue up the mountain. Do not let this prospect cloud anyone’s judgement. Be willing to admit that you or your companion has altitude sickness. As soon as feelings of illness arise the symptoms should be recognised and acted upon.
Remember, the golden rules for avoiding AMS are: ascend slowly. If you start to feel the onset of symptoms of AMS go no higher. If the symptoms persist, descend at once.
Porters and AMS
While on the mountain it is important to remember that the porters can be affected by AMS just as readily as you. Although most of them have been to altitude before and are likely to be better acclimatised than their charges, they may still suffer from the condition. The fact that they are unlikely to know much about AMS, have a communication barrier that prevents them from explaining in detail how they feel and may actively conceal their symptoms so as not to lose their jobs makes them susceptible to the more extreme versions of the condition.
DIAMOX (ACETAZOLAMIDE)
Diamox can aid acclimatisation. However, it is not a substitute for a slow and appropriate ascent and should not be taken as a matter of course. Most people with a reasonable rate of ascent will not need it. You must seek guidance from a GP before taking Diamox. The dosage required is based on your body weight, although 125mg (half a tablet) two or three times a day is usually enough to have an effect. Diamox re-acidifies the blood, balancing the effects of the hyperventilation that occurs at altitude in an attempt to get sufficient oxygen. This in turn acts as a respiratory stimulant, whose end effect is to accelerate acclimatisation.
It is not a magic cure, however. Diamox doesn’t cover up the symptoms of AMS. Neither does it protect you from worsening AMS if you continue to ascend after symptoms have been diagnosed. Although it may reduce the time it takes for you to acclimatise, it will not totally prevent you from suffering from AMS. If you still feel sick after taking Diamox, you must descend.
If you take Diamox remember to increase your level of fluid intake as the drug is a diuretic and you may become more prone to dehydration. There are also several other side effects of using the drug. You may feel a numbness or tingling sensation in your hands, feet and lips. These may be accompanied by a ringing sound