HIGH ALTITUDE AND OTHER RELATED HEALTH PROBLEMS ON KILIMANJARO

HIGH ALTITUDE AND OTHER RELATED HEALTH PROBLEMS

ON KILIMANJARO

THE PURPOSE OF THIS REVIEW

Every year more and more climbers attempt to conquer Mount Kilimanjaro and many of them seem to be totally ignorant of the basic facts of altitude sickness. Even worse seems to be the fact that many tour operators have no or very limited knowledge of this potentially fatal sickness and fail to provide their clients with even basic information. There is little doubt that altitude illness is a one hundred percent preventable illness, and therefore no one should ever die from it.
High altitude illness is, for obvious reasons, of great concern to Destination Africa Tours. Providing our clients with the best possible knowledge in this regard is something we are totally committed to. The main purpose of this review, presented exclusively to the clients of Destination Africa Tours, is as follows:

- To provide you with guidelines which will hopefully simplify the issues of altitude sickness,
- To provide you with important prophylactic (preventative) advice, to be followed during your trek,
- To review and familiarise you with the different diagnosis of altitude sickness,
- To guide you on what to do should you experience symptoms of altitude sickness during your trek,
- To help you with your pre-trekking decisions.

We strongly advice you to take a printed copy of these guidelines on your trek, as a field reference for the duration of your climb.

HIGH ALTITUDE

Definition of High Altitude:

- High Altitude: 1500 – 3500 m (5000 – 11500 ft)
- Very High Altitude: 3500 – 5500 m (11500 – 18000 ft)
- Extreme Altitude: above 5500 m

Practically speaking, however, we generally don't worry much about elevations below about 2500 m (8000 ft) since altitude illness rarely occurs lower than this. From the above it is clear that Kilimanjaro falls within the definition of “extreme altitude” and should be treated as such!

NORMAL ACCLIMATIZATION

Acclimatization is the process of the body adjusting to the decreased availability of oxygen at high altitudes. It is a slow process, taking place over a period of days to weeks. Acclimatization seems to be under genetic control. Some people adjust very easily to high altitude, and others cannot get above relatively moderate heights of 3000 m. The ease with which someone can acclimatize is normally fairly consistent from trip to trip.
Human bodies have built-in adjustment mechanisms that can optimise performance at higher altitudes. This process is known as acclimatization, the power thereof can be demonstrated by the following example:

If a person were transported suddenly to the summit of Mt. Everest (8848 m), the person would lose consciousness in a few minutes, and most likely die within an hour or two due to an acute condition of low oxygen concentration in the blood (hypoxia). However, over 60 people have climbed to the summit of Mt. Everest without using supplemental oxygen after acclimatizing for many weeks. This fact demonstrates how profound the process of acclimatization can be.

As one ascends through the atmosphere, every breath contains fewer and fewer molecules of oxygen. One must work harder to obtain oxygen, by breathing faster and deeper. This is particularly noticeable with exertion, such as walking uphill. Being out of breath with exertion is normal, as long as the sensation of shortness of breath resolves rapidly with rest. The increase in breathing is critical. It is therefore important to avoid anything that will decrease breathing, e.g. alcohol and certain drugs. Despite the increased breathing, attaining normal blood levels of oxygen is not possible at high altitude.

Certain normal physiologic changes occur in every person who goes to altitude:

- Hyperventilation (breathing faster, deeper, or both)
- Shortness of breath during exertion
- Changed breathing pattern at night/periodic breathing
- Awakening frequently at night
- Increased urination

AN INTRODUCTION TO ALTITUDE SICKNESS

The process of acclimatization is still poorly understood medically. Traditionally, researchers focused on the increase in erythropoetin, and the gradual increase in red blood cells as being crucial. However, it now recognized that this process plays only a small role, and that increases in respiration (minute ventilation), and other more subtle adaptations at the hormonal and cellular level may be more important. If a person ascends slowly enough, these adaptive processes can take place effectively, and no illness will occur. If the person ascends more rapidly than the body can adjust, however, symptoms occur that are referred to as altitude illness.

Altitude illness is generally divided into mainly three syndromes:

- Acute mountain sickness (AMS)
- High altitude pulmonary edema (HAPE)
- High altitude cerebral edema (HACE)
(Edema: swelling caused by an abnormal accumulation of fluid in body tissues)
These syndromes are believed to be connected, but just why cerebral symptoms predominate in some people and pulmonary symptoms predominate in others is not known.

Acute mountain sickness and High altitude cerebral edema
The cerebral form HACE of altitude illness begins as acute mountain sickness (AMS). AMS presents as headache, loss of appetite (anorexia), and fatigue. The headache can progress from mild to excruciating, and anorexia can lead to nausea and vomiting. The fatigue can progress to a feeling of extreme lack of interest or energy (lassitude). At some point, when the symptoms are severe enough, the syndrome becomes known as high altitude cerebral edema.

High altitude pulmonary edema
HAPE can present with or without cerebral symptoms. If pulmonary symptoms do occur alone, the progression is from decreased exercise tolerance—increased difficulty walking up hill—to severe breathlessness with exertion, substernal chest fullness, and ultimately breathlessness at rest.

Other syndromes
Some people at altitude develop peripheral edema, there may be swelling around the eyes, fingers, ankles at high altitude, but this may not indicate AMS unless accompanied by the symptoms of AMS. These symptoms without AMS usually require no treatment. As the person with peripheral edema acclimatizes, they often experience a profound diuresis and relief of symptoms. One can ascend with peripheral edema, but one needs to be extra cautious about the development of other symptoms.
High altitude retinopathy refers to the development of retinal haemorrhages while staying at high altitude. Usually only discovered when searched for by trained doctors.
High altitude syncope (fainting): This is well known but harmless problem, in which fainting occurs suddenly, usually shortly after arrival. Simple measures like keeping the individual in a reclining position and raising the legs is helpful.

THE ACCLIMATIZATION LINE

A person travelling to high altitude can be taught to understand the process of acclimatization and illness through a concept known as the "acclimatization line." A group of people standing at sea level would each have a hypothetical thin line at around 3000 m, below which they will feel fine, and above which they would experience symptoms of altitude illness. The height of this acclimatization line would vary genetically with each individual. If the person ascends to altitude, but stays below the acclimatization line, there will be no symptoms, and the process of acclimatization can take place.
After a night at 3000 m, one’s acclimatization line will rise, perhaps to 3500 m. If one moves up the next day to 3400 m, one would remain asymptomatic and continue to acclimatize. However, if the person moves up to 3600 m, symptoms of AMS would ensue. It appears that if one’s symptoms begin to occur very near to the acclimatization line, the body can continue to adjust, and a day’s rest at the same height will result in resolution of symptoms. If the symptoms at 3600 m are ignored, however, and the person moves up another 500 m or so, the symptoms will continue to worsen and further adaptation will not take place. It is then necessary to get below the point where the symptoms began in order to start seeing improvement. This last point illustrates why it is so dangerous to ascend with any symptoms of altitude illness.

DIAGNOSIS OF ALTITUDE SICKNESS

1. GENERAL

The diagnosis of altitude illness at altitude requires a high index of suspicion. Trekkers have been advised for years that: "If you are not doing well at altitude, it’s altitude illness until proven otherwise." This is sound advice, and was formulated to assure that altitude illness is considered in the differential diagnosis of any illness at altitude.

The symptoms of altitude illness almost always have a gradual onset, and get worse slowly over several hours.

The history of any altitude related symptoms at any of the prior heights should be elicited.
In order for symptoms to be attributed to altitude illness, they must begin as the person is ascending. A person who has been asymptomatic at the high point of a trek cannot develop AMS while descending. In almost all instances of severe altitude illness, the history will elicit symptoms of AMS at a lower height that were ignored or attributed to something else by the patient.

Virtually all life-threatening altitude illness is due to ascending with recognizable symptoms. This point cannot be stressed enough, as the key point in preventing severe altitude illness.

2. ACUTE MOUNTAIN SICKNES (AMS)

DESCRIPTION

AMS is caused by a lack of oxygen. Although the proportion of oxygen in the atmosphere always remains the same (21%), as we go higher the "driving pressure" decreases. The driving pressure depends directly on the barometric pressure, and forces oxygen from the atmosphere into the capillaries of the lungs. Reduced driving pressure results in decreased saturation of oxygen in the blood and throughout the tissues.
AMS is a constellation of symptoms that represents your body not being acclimatized to its current altitude. Anyone who goes to altitude can get AMS. It is primarily related to individual physiology (genetics) and the rate of ascent; there is no significant effect of age, gender, physical fitness, or previous altitude experience. Some people acclimatize quickly, and can ascend rapidly; others acclimatize slowly and have trouble staying well even on a slow ascent. This brain tissue distress causes a number of symptoms; universally present is a headache, along with a variety of other symptoms.

RECOGNISE THE SYMPTOMS

The diagnosis of AMS is made when a headache, with any one or more of the following symptoms is present after a recent ascent above 2500 m (8000 ft)

- Loss of appetite, nausea, or vomiting
- Fatigue or weakness
- Dizziness or light-headedness
- Difficulty sleeping

All of these symptoms may vary from mild to severe. A scoring system has been developed based on the Lake Louise criteria for a simple method to evaluate an individual's AMS severity.

AMS has been likened to a bad hangover, or worse. However, because the symptoms of mild AMS can be somewhat vague, a useful rule-of-thumb is:

I you feel unwell at altitude; it is altitude sickness unless there is another obvious explanation (such as Diarrhea).

HEADACHE AND FEVER

A frequent question is how to tell if a headache is due to altitude. Altitude headaches are usually nasty, persistent, and frequently there are other symptoms of AMS; they tend to be frontal (but may be anywhere), and may worsen with bending over. The headache often starts at the back of the head and radiates forward, and is constant in nature. But a throbbing frontal headache can also be due to altitude. It is imperative that all headaches at altitude are treated as altitude headaches, and no further ascent is attempted until any headache has disappeared. There is no sense betting one’s life that the current headache is not due to altitude
However, there are other causes of headaches, and you can try a simple diagnostic/therapeutic test. Dehydration is a common cause of headache at altitude. Drink one litre of fluid, and take some acetaminophen (a pain-relieving and fever-reducing non narcotic drug). If the headache resolves quickly and totally (and you have no other symptoms of AMS) it is very unlikely to have been due to AMS. It is remarkable how many people mistakenly believe that a headache at altitude is "normal"; it is not. Denial is also common.

Fever can occur with HACE or HAPE, and can be a confusing finding. If the history and symptoms are compatible with altitude illness, the fever can usually be attributed to the altitude illness. However, fever would only present, in these cases, after the onset of other AMS symptoms. A fever that pre-dates the symptoms of altitude illness should be attributed to other causes.

WHAT TO DO

The mainstay of treatment of AMS is not to ascend any further (not until all symptoms of altitude illness have disappeared), rest, fluids, and mild analgesics (pain-relieving drugs): acetaminophen paracetamol, aspirin, or ibuprofen. These medications will not cover up worsening symptoms. The natural progression for AMS is to get better, and often simply resting at the altitude at which you became ill is adequate treatment. Improvement usually occurs in one or two days, but may take as long as three or four days. Descent is also an option, and recovery will be quite rapid.

Be willing to admit that you have altitude illness, that's the first step to staying out of trouble.

3. HIGH ALTITUDE CEREBRAL EDEMA (HACE)

DESCRIPTION

AMS is a spectrum of illness, from mild to life threatening. At the "severely ill" end of this spectrum is High Altitude Cerebral Edema (Edema: swelling caused by an abnormal accumulation of fluid in body tissues); this is when the brain swells and ceases to function properly. HACE is probably caused by shifts of fluid into the tissues of the brain. Reduced oxygen levels cause swelling within the confines of the bony skull. The resulting rise in pressure may lead to lethargy (inactivity; showing an unusual lack of energy) and eventually coma. HACE can progress rapidly, and can be fatal in a matter of a few hours to one or two days. Persons with this illness are often confused, and may not recognize that they are ill.

RECOGNISE THE SYMPTOMS

The hallmark of HACE is a change in mentation, or the ability to think. There may be confusion, changes in behaviour, or lethargy. There is also a characteristic loss of coordination that is called ataxia (failure of muscular coordination; irregularity of muscular action). This is a staggering walk that is similar to the way a person walks when very intoxicated on alcohol. This loss of coordination may be subtle, and must be specifically tested for. Have the sick person do a straight-line walk (the "tandem gait test"). Draw a straight line on the ground, and have them walk along the line, placing one foot immediately in front of the other, so that the heel of the forward foot is right in front of the toes behind. Try this yourself. You should be able to do it without difficulty. If they struggle to stay on the line (the high-wire balancing act), can't stay on it, fall down, or can't even stand up without assistance, they fail the test and should be presumed to have HACE.

WHAT TO DO

Immediate descent is the best treatment for HACE. This is of the utmost urgency, and cannot wait until morning (unfortunately, HACE often strikes at night). Delay may be fatal. The moment HACE is recognized is the moment to start organizing flashlights, helpers, porters; whatever is necessary to get this person down. Descent should be to the last elevation at which they woke up feeling well. Bearing in mind that the vast majority of cases of HACE occur in persons who ascend with symptoms of AMS, this is likely to be the elevation at which the person slept two nights previously. If you are uncertain, a 500-1000 m descent is a good starting point. Other treatments include oxygen, hyperbaric bag, and dexamethasone (a steroid that is sometimes used following a brain injury, to help reduce swelling in the brain). These are usually used as temporising measures until descent can be affected.

For more information in this regard please refer to the section “Treatment of altitude sickness” below. People with HACE usually survive if they descend soon enough and far enough, and usually recover completely. The staggering gait may persist for days after descent. Once recovery has been complete, and there are no symptoms, cautious re-ascent is acceptable.

4. HIGH ALTITUDE PULMONARY EDEMA (HAPE )

DESCRIPTION

Another form of severe altitude illness is High Altitude Pulmonary Edema, or fluid in the lungs. Though it often occurs with AMS, it is not felt to be related and the classic signs of AMS may be absent. The typical scenario would be a trekker who has no headache or nausea, but finds he has a harder time walking uphill, that he is out of breath on slight exertion compared with the initial days of the trek. (Edema: swelling caused by an abnormal accumulation of fluid in body tissues)

RECOGNISE THE SYMPTOMS

Signs and symptoms of HAPE include any of the following:
- Extreme fatigue
- Breathlessness at rest
- Fast, shallow breathing
- Cough, possibly productive of frothy or pink sputum
- Gurgling or rattling breaths
- Chest tightness, fullness, or congestion
- Blue or grey lips or fingernails
- Drowsiness

Once again HAPE usually occurs at night and is more frequent in young, fit climbers or trekkers. HAPE presents with unusual breathlessness upon exertion, and eventually at rest as well. Cough is usually present, but cough at high altitude is so common from other causes that it is rarely a useful clinical sign of HAPE.

Low oxygen causes the pulmonary artery to narrow and this results in exudation of blood near the smaller branches of the lungs (the alveoli). If the exudation continues, blood may escape into the alveoli leading to a cough with watery, blood-tinged phlegm. Such exudation, or "water logging" of the lung tissue interferes further with oxygenation.
It is common for persons with severe HAPE to also develop HACE, presumably due to the extremely low levels of oxygen in their blood (equivalent to a continued rapid ascent).

WHAT TO DO

Immediate descent is mandatory as soon as HAPE can be suspected, as the symptoms can progress rapidly, and death can occur within hours of recognizing clinical HAPE. Unless oxygen is available delay may be fatal. Descend to the last elevation where the victim felt well upon awakening. Descent may be complicated by extreme fatigue and possibly also by confusion due to inability to get enough oxygen to the brain; HAPE frequently occurs at night, and may worsen with exertion. These victims often need to be carried. Unfortunately, exertion considerably worsens HAPE. Exertion by the sick person should be minimized during descent, but this is not always possible.

Rest, oxygen, rehydration, and for severe cases, nifedipine or salmeterol. For more information in this regard please refer to the section “Treatment of altitude sickness” below.
HAPE resolves rapidly with descent, and one or two days of rest at a lower elevation may be adequate for complete recovery. Once the symptoms have fully resolved, cautious re-ascent is acceptable.

Occasionally, climbers with apparent HAPE have died a pulmonary death despite several thousand feet of descent. It has been postulated that some of these deaths may have been due to the problem of exerting during descent.

HAPE CAN BE CONFUSED WITH A NUMBER OF OTHER RESPIRATORY CONDITIONS:

High Altitude Cough and Bronchitis are both characterized by a persistent cough with or without sputum (mucus coughed up from the lungs) production. There is however no shortness of breath at rest, no severe fatigue.

Pneumonia

Can be difficult to distinguish from HAPE. Fever is common with HAPE and does not prove the patient has pneumonia. Coughing up green or yellow sputum may occur with HAPE, and both can cause low blood levels of oxygen. The diagnostic test (and treatment) is descent - HAPE will improve rapidly. If the patient does not improve with descent, then consider antibiotics. HAPE is much more common at altitude than pneumonia, and more dangerous; many climbers have died of HAPE when they were mistakenly treated for pneumonia.

Asthma

Might also be confused with HAPE. Fortunately, asthmatics seem to do better at altitude than at sea level. If you think it's asthma, try asthma medications, but if the person does not improve fairly quickly assume it is HAPE and treat it accordingly.

THE TREATMENT OF ALTITUDE ILLNESS

1. REST AT SAME ELEVATION

The mainstay of treatment of AMS is rest, fluids, and mild analgesics (pain-relieving drugs): acetaminophen paracetamol, aspirin, or ibuprofen. These medications will not cover up worsening symptoms. The natural progression for AMS is to get better, and often simply resting at the altitude at which you became ill is adequate treatment. Improvement usually occurs in one or two days, but may take as long as three or four days.

2. DESCENT

It was once written that altitude illness had three treatments: descent, descent, and descent. Descent remains the critical treatment of all altitude syndromes, but the availability of bottled oxygen, the invention of pressurization bags, and the recognition of the value of three medications—acetazolamide, nifedipine, and dexamethasone--have expanded the choices when confronted with altitude illness. Patients with HAPE need to descend slowly and with assistance: excessive exertion even during descent may increase the blood flow to the lungs and exacerbate the problem

Descent invariably improves altitude illness. However, in severe cases, descent must continue either until clear signs of improvement are recognized, or the person is below the altitude at which his symptoms have started. It is not necessary to descend until all symptoms are gone, as this can take up to 48-72 hours to take place. Any sign of improvement usually heralds the crossing of the acclimatization line, and further improvement can be expected.

3. ACETAZOLAMIDE (DIAMOX®)

Description

Acetazolamide is the most tried and tested drug for altitude sickness prevention and treatment. Unlike dexamethasone this drug does not mask the symptoms but actually treats the problem. It seems to works by increasing the amount of alkali (bicarbonate) excreted in the urine, making the blood more acidic. Acidifying the blood drives the ventilation, which is the cornerstone of acclimatization.
This re-acidification acts as a respiratory stimulant, particularly at night, reducing or eliminating the periodic breathing pattern common at altitude. Its net effect is to accelerate acclimatization. However Acetazolamide isn't a magic bullet and cure of AMS is not immediate. It makes a process that might normally take about 24-48 hours speed up to about 12-24 hours. Initially it was given for three days before ascent, but it is now thought that starting the day before is adequate

Cautions

Acetazolamide is a sulphonamide medication (a class of sulphur-containing antibiotic drugs (e.g., sulphadiazine) which cause sensitivity or adverse reactions in many people, and persons allergic to sulpha medicines should not take it. Common side effects include numbness, tingling, or vibrating sensations in hands, feet, and lips. Also, taste alterations, and ringing in the ears. These go away when the medicine is stopped. Since acetazolamide works by forcing a bicarbonate diuresis (significantly increasing the production of urine), you will urinate more on this medication. Uncommon side effects include nausea and headache. A few trekkers have had extreme visual blurring after taking only one or two doses of acetazolamide; fortunately they recovered their normal vision in several days once the medicine was discontinued.

Acetazolamide Use & Dosage:

For treatment of AMS:
We recommend a dosage of 250 mg every 12 hours. The medicine can be discontinued once symptoms resolve. Children may take 2.5 mg/kg body weight every 12 hours.

For Periodic Breathing:
125 mg about an hour before bedtime. The medicine should be continued until you are below the altitude where symptoms became bothersome.

Myths about Acetazolamide

Myth: Acetazolamide hides symptoms
Acetazolamide accelerates acclimatization. As acclimatization occurs, symptoms resolve, directly reflecting improving health. Acetazolamide does not cover up anything - if you are still sick, you will still have symptoms. If you feel well, you are well.
Myth: Acetazolamide will prevent AMS from worsening during ascent
Acetazolamide does not protect against worsening AMS with continued ascent. It does not change Golden Rule II as described later in this guideline. Plenty of people have developed HAPE and HACE who believed this myth.
Myth: Acetazolamide will prevent AMS during rapid ascent
This is actually not a myth, but rather a misused partial truth. Acetazolamide does lessen the risk of AMS, that's why we recommend it for people on forced or rapid ascents. This protection is not absolute, however, and it is foolish to believe that a rapid ascent on acetazolamide is without serious risk. Even on acetazolamide, it is still possible to ascend so rapidly that when illness strikes, it may be sudden, severe, and possibly fatal.
Myth: If acetazolamide is stopped, symptoms will worsen
There is no rebound effect. If acetazolamide is stopped, acclimatization slows down to your own intrinsic rate. If AMS is still present, it will take somewhat longer to resolve; if not - well, you don't need to accelerate acclimatization if you ARE acclimatized. You won't become ill simply by stopping acetazolamide.

Periodic breathing / sleep apnea

Acetazolamide is also a very effective tool for treating the periodic breathing and sleep apnea that occurs at altitude. Controlled studies showed a marked decrease in both periodic breathing and a concomitant (occurring simultaneously) drop in arterial oxygen saturation when acetazolamide was taken prior to bedtime. If a person sleeping at altitude is troubled by awakening with a profound sense of breathlessness, acetazolamide 125 mg at bedtime will effectively eliminate this problem. However, it should be pointed out that there are many reasons that people don’t sleep well at high altitude, including crowded lodges, lumpy ground, going to bed at 7:00 p.m., and so forth. Therefore, a careful history should be taken as to why sleep is difficult at altitude before routinely recommending acetazolamide

4. DEXAMETHASONE (DECADRON®)

Description

Dexamethasone (Decadron®) is a potent steroid (a hormone-like drug that reduces swelling and inflammation) which can be life saving in people with HACE, and works by decreasing swelling and reducing the pressure in the bony skull. Whereas acetazolamide treats the problem (by accelerating acclimatization), dexamethasone treats the symptoms (the distress caused by hypoxia). Dexamethasone can completely remove the symptoms of AMS in a few hours, but it does not help you acclimatize. If you use dexamethasone to treat AMS you should not go higher until the next day, to be sure the medication has worn off and is not hiding a lack of acclimatization.

Cautions

Side effects include euphoria in some people, trouble sleeping, and an increased blood sugar level in diabetics. Currently, it is felt that dexamethasone can be safely used to facilitate the evacuation of someone with relatively severe AMS or HACE. Once dexamethasone is given, the person should not move up to sleep at a higher elevation until dexamethasone has been discontinued for 24 hours or more.

Dexamethasone Use & Dosage:

For treatment of AMS: Two doses of 4 mg, 6 hours apart. This can be given orally, or by an injection if the patient is vomiting. Children may be given 1 mg/kg of body weight, up to 4 mg maximum; a second dose is given in 6 hours. Do not ascend until at least 12 hours after the last dose, and then only if there are no symptoms of AMS.

5. NIFEDIPINE

This drug is generally used to treat high blood pressure, but also seems able to decrease the narrowing in the pulmonary (pertaining to the lungs) artery caused by low oxygen levels, thereby improving oxygen transfer. It can therefore be used to treat HAPE, though unfortunately its effectiveness is not anywhere as dramatic that of dexamethasone in HACE. It can cause sudden lowering of blood pressure so the patient has to be warned to get up slowly from a sitting or reclining position. It has also been used in the same dosage to prevent HAPE in people with a past history of this disease.

Nifedipine Use & Dosage:

The dosage is 20 mg of long acting nifedipine, six hourly.

6. OXYGEN

Lack of oxygen at altitude is the chief reason why people suffer from altitude sickness, so breathing supplemental oxygen is obviously going to make a difference. AMS symptoms resolve very rapidly (minutes) on moderate-flow oxygen (2-4 litres per minute, by nasal cannula). There may be rebound symptoms if the duration of therapy is inadequate - several hours of treatment may be needed. In most high altitude environments, oxygen is a precious commodity, and as such is usually reserved for more serious cases of HACE and HAPE.

7. HYPERBARIC THERAPY

This is a simple, effective device, made of airtight nylon; it is about 7 feet long ad looks like a long duffel bag. With the patient inside, the bag is inflated with a foot pump until it becomes like a large sausage-shaped balloon. There is a one-way valve to avoid carbon dioxide build up inside, and it has transparent panels to assist communication with its occupant.
The pressure inside the bag is 2 p.s.i,. so the effect is about the same as bringing the patient down a couple of thousand feet. For both HACE and HAPE (but especially, for HACE) the changes are usually dramatic within an hour. However there may be a "rebound" two or three hours after therapy and the patient may need to get in the bag again. Just like the dexamethasone, this bag only helps to "buy time". Descent is still mandatory as soon as possible.

EVALUATION OF AMS TREATMENT OPTIONS

i RAPID DESCENT

Pros: Rapid recovery: trekkers generally improve during descent and recover totally within several hours.

Cons: Loss of "progress" toward trek goal; descent may be difficult in bad weather or at night; personnel needed to accompany patient.

ii REST AT SAME ELEVATION

Pros: Acclimatization to current altitude, no loss of upward progress.

Cons: It may take 24-48 hours to become symptom-free

iii REST PLUS ACETAZOLAMIDE

Pros: As with rest alone, plus acclimatization is accelerated, recovery likely within 12-24 hours

Cons: Recovery may take 12-24 hours; side effects of acetazolamide.

iv REST PLUS DEXAMETHASONE

Pros: Faster resolution of symptoms than with acetazolamide (usually in a few hours); minimal side effects; cheap

Cons: Can hide symptoms & thus give a false sense of security to those who want to continue upwards. Does not accelerate acclimatization.

v REST PLUS DEXAMETHASONE & ACETAZOLAMIDE

Pros: Fast resolution of symptoms from the dexamethasone, plus improved acclimatization from the acetazolamide

Cons: Side effects of acetazolamide. Same cautions as above regarding ascent after taking dexamethasone.

vi OXYGEN OR HYPERBARIC THERAPY

Pros: Very rapid relief of symptoms (minutes).

Cons: Expensive; hyperbaric bags are very labour-intensive; rebound symptoms may occur if treatment is too short - several hours are needed.

PREVENTING ALTITUDE ILLNESS

There is little doubt that altitude illness is one hundred percent a preventable illness. No one should die from it. There are four golden rules, plus some important general principles that should always be followed:

1. THE FOUR GOLDEN RULES TO PREVENT ALTITUDE ILLNESS:

I Learn the early symptoms of altitude illness and be willing to recognize when you have them.

II Never ascend to sleep at a higher altitude with any symptoms of altitude illness.

III Descend if your symptoms are getting worse while resting at the same altitude.

IV Group members must look out for one another

When cases of fatal altitude illness are reviewed, we almost invariably find that the person ascended with symptoms that could have been recognized as due to altitude illness. In most of these cases, the symptoms were either ignored, minimized, or attributed to another cause.

Most symptoms of altitude illness occur after spending the night at a higher altitude. If the rate of ascent has been reasonable, these symptoms usually resolve with a day’s rest at the same altitude. However, if the person’s symptoms continue to worsen during the day, descent is mandatory. Usually this decision should be made by around 3:00 p.m. in a trekking setting so that descent can be made during daylight. However, descent should never be delayed because it is "too late" in the day.
Symptoms can either begin while ascending to a new camp, or after spending the night at the new height. In general, symptoms that begin in the morning after spending the night at a new altitude are more likely to clear up with rest at the same altitude than symptoms that began the day before while ascending to the camp.

2. RESIST GROUP PRESSURE

In organized trekking groups, there is a great deal of pressure to keep up with the group schedule or be left behind. Since leaving a client behind is problematic logistically for a guide of a trekking group, even the guide can contribute to the denial of altitude symptoms. Trekkers who are travelling with an organized trekking group may have a false sense of security in regard to their risk of dying from altitude illness. A 1991 study showed that trekkers in organized trekking groups had a statistically significant increased risk of dying compared to trekkers who were not in an organized group. This fact emphasizes that group pressure and the reluctance to be left behind if one admits symptoms is a risk factor for dying from altitude illness. Thus, being willing to recognize altitude symptoms when they are present is a key point.
AMS symptoms will invariably worsen with ascent. Occasionally, however, it is necessary to ascend in order to get to a lower altitude, such as crossing a pass. If the symptomatic person appears to have the ability to make it over the pass, and will sleep at a lower altitude that night, this is a risk that can be taken. But no one with any symptoms of altitude illness should ascend to sleep at a higher altitude.

3. FOLLOWING A CONSERVATIVE RATE OF ASCENT

Going too high, too quickly, is the single most important cause of susceptibility to AMS.
The key to avoiding AMS is a gradual ascent that gives your body time to acclimatize. People acclimatize at different rates, so no absolute statements are possible, but in general, the following recommendations will keep most people from getting AMS

- If possible, you should spend at least one night at an intermediate elevation below 3000 m.
- Beyond about 3000 m (10,000 ft), the sleeping altitude should be no higher than about 500 m (1500 ft) from the previous night's altitude.
- Every 1000 m (3000 ft) you should spend a second night at the same elevation.
- Remember, it's how high you sleep each night that really counts; not the altitude achieved during the daytime. Altitude sickness often manifests at night because during sleep the oxygen level in the blood may dip further. The day hikes to higher elevations that you take on your "rest days" (when you spend a second night at the same altitude) help your acclimatization by exposing you to higher elevations, then you return to a lower (safer) elevation to sleep. This second night also ensures that you are fully acclimatized and ready for further ascent.

From the above it is clear that the available current Kilimanjaro ascent routes all exceed the suggested conservative recommended ascend rates above. This is due to the various heights of the overnight camps/huts en route. For some unknown reason KINAPA (Kilimanjaro National Parks Board forces trekkers to overnight only at these “official” camps/huts. This compels trekkers to ascend on average about 1000 m per day – double the accepted conservative ascend rate which, for obvious reason further increases the risk of altitude sickness to Kilimanjaro trekkers.

It is mainly for this reason that Destination Africa Tours strongly advise all it clients to provide for an extra day of acclimatisation. It is also mainly for this reason that we highly recommend the Machame route on which trekkers sleep at roughly the same altitude (3840 m and 3950 m) for two consecutive nights as part of the standard route – providing for the much needed extra day of acclimatization.

4. AVOIDING OF EXCESSIVE EXERTION IN THE INITIAL DAYS

Excessive physical exertion at high altitude makes one more susceptible to AMS. It is important to take it easy at high altitude, especially in the initial days. People who are very fit for example marathon runners or those who carry very heavy backpacks seem more vulnerable to AMS than others, probably because they push themselves harder. I once looked after a trekker who felt he could not break his morning jogging sessions despite a strenuous trek day ahead, even at 4000m! The feeling of "man against nature" may be stronger in this fitter group.

5. THINGS TO AVOID

Respiratory depression (the slowing down of breathing) can be caused by various medications, and may be a problem at altitude. The following medications can do this, and should never be used by someone who has symptoms of altitude illness (these may be safe in persons who are not ill, although this remains controversial).

- Alcohol
- Sleeping pills (
- Narcotic pain medications in more than modest doses

Alcohol may dehydrate the trekker but more importantly it depresses breathing or ventilation. Sleeping pills may have a similar effect.

6. PROPHYLAXIS FOR HIGH ALTITUDE ILLNESS

Under certain circumstances, prophylaxis (prevention) with medication may be advisable.

- For persons on forced rapid ascents (for climbers who cannot avoid a big altitude gain due to terrain considerations, or for rescue personnel on a rapid ascent
- For persons who have repeatedly had AMS in the past

Acetazolamide

We do not recommend acetazolamide as a prophylactic (preventative) medication, except under the specific limited conditions outlined above. Most people who have a reasonable ascent schedule will not need it, and in addition to some common minor but unpleasant side effects it carries the risk of any of the severe side effects that may occur with sulphonamides.

The dose of acetazolamide for prophylaxis is 125-250 mg twice a day starting 24 hours before ascent, and discontinuing after the second or third night at the maximum altitude (or with descent if that occurs earlier). Sustained release acetazolamide, 500 mg, is also available and may be taken once per day instead of the shorter acting form, though side effects will be more prominent with this dose.

Ginkgo biloba extract

Recently some exciting work has been done studying the use of Ginkgo biloba extract to prevent AMS. Much more work remains to be done, but in three studies Ginkgo has been shown to be very effective in preventing or lessening the symptoms of AMS. It has yet to be determined exactly how Ginkgo works at altitude, but it may act as an antioxidant, reducing stress on tissues that have been injured by low oxygen levels.

These studies used a standardized Ginkgo biloba extract (24% flavonoid glycosides, 6% terpenoids). The dose used was 80 - 120 mg twice a day, starting 5 days before a rapid ascent or at the beginning of a gradual ascent.

MAINTAINING ADEQUATE HYDRATION

Adequate amounts of fluid (about 3 litres a day) are necessary in the mountains:- dehydration mimics altitude sickness and may even predispose to it. On the other hand excessive water drinking should also be avoided as this may lead to electrolyte imbalances.

7. PREVENTING SEVERE AMS

This simply cannot be emphasized too much. If you have symptoms of AMS, DO NOT ASCEND ANY HIGHER. Violating this simple rule has resulted in many tragic deaths.

If you ascend with AMS you will get worse, and you might die. This is extremely important even a day hike to a higher elevation is a great risk. In many cases of High Altitude Cerebral Edema, this rule was violated. Stay at the same altitude (or descend) until your symptoms completely go away. Once your symptoms are completely gone, you have acclimatized and then it is OK to continue ascending. It is always OK to descend, you will get better faster.

CONCLUSION

Most of the problems of high altitude are totally preventable. With careful precautions, your experience on Mount Kilimanjaro should be safe and rewarding.
It is OK to get altitude illness, it can happen to anyone. It is not OK to die from it, because as mentioned before it is 100% preventable. With the information in these guidelines, you should be able to avoid the severe, life-threatening forms of altitude illness.

DISCLAIMER

The above information is not intended to represent a medical guide or information. Destination Africa Tours therefore takes no responsibility for any harm, injury or death any person might suffer as a direct or indirect result from following any advice or suggestions represented in the above document in anyway. You are strongly advice to discuss all aspects of altitude sickness with your medical doctor.