Hypobaropathy

Description:

Hypobaropathy (high-rise hypoxia) — the disease state connected with air hunger owing to decrease in partial pressure of oxygen in the inhaled air which arises highly in mountains, and also when flying on the aircraft which are not equipped with a tight cabin (for example, paraplanes, hang-gliders, balloons), since about 2000 meters and above over the level of oceans.

Kind of a hypobaropathy is the mountain disease in which emergence along with a lack of oxygen such additional factors as physical exhaustion, cooling, organism dehydration, ultraviolet radiation, severe weather conditions (for example, gale-force winds), sharp differences of temperatures during the day (from +30 C day to −20 play also a role at the C night) etc. But the major pathological factor of a mountain disease is the hypoxia.

The person is capable to adapt to a high-rise hypoxia, athletes use these types of adaptation to raise the sports characteristics. Heights from 8000 meters after which there comes death are considered as a limit of possible adaptation.

Hypobaropathy reasons:

Height at which the mountain disease develops varies owing to influence of numerous factors, both individual, and climatic.

Development of a mountain disease is influenced by the following individual factors:
individual resistance of people to a lack of oxygen (for example, at inhabitants of mountains);
floor (women have a hypoxia better);
age (young people badly have a hypoxia);
physical, mental and morale;
fitness level;
speed of ascent;
degree and duration of air hunger;
intensity of muscular efforts;
last "high-rise" experience.

The following factors provoke development of a mountain disease and reduce portability of big heights:
availability of alcohol or caffeine in blood;
sleeplessness, overfatigue;
psychoemotional tension;
overcooling;
low-quality and irrational food;
disturbance of the water-salt mode, dehydration;
excess body weight;
respiratory and other chronic diseases (for example quinsy, bronchitis, pneumonia, chronic purulent dental diseases);
blood losses.

The following climatic factors promote development and more bystry progressing of a mountain disease
Low temperatures — with increase in height annual average air temperature gradually decreases on 0,5 C by each 100 m (winter 0,4 C, in the summer 0,6 C). In the winter as equals heights incidence more frequent, than in the summer. The sharp difference of temperatures exerts adverse impact too.
Humidity — at big heights because of low temperatures the partial pressure of water vapor low. At the height of 2000 m and above in two air humidity and more time are less, than at sea level, in the same area.

At big mountain heights air becomes almost dry (partial pressure of saturated water vapor is insignificant). On the one hand, it leads to liquid loss strengthening by an organism through skin and lungs and, therefore, to organism dehydration. On the other hand, more wet air at sea climate has much higher heat conductivity (heat conductivity is almost linearly connected with the molecular mass of molecules, at water, 18 g/mol, at air - mix of gases of 29 g/mol), therefore, promotes an adverse effect of low temperatures; and also vapors of water force out oxygen from alveoluses of lungs, lowering its already low contents.
Wind — highly in mountains wind can reach the storm force (over 200 km/h) that overcools an organism, exhausts physically and morally, complicates breath.

Hypobaropathy symptoms:

The acute form of a mountain disease arises at bystry movement (within several hours) unacclimatized people in highlands, usually on height more than 3500 m. Its clinical symptoms develop promptly. At a subacute form of a mountain disease they develop not so quickly and remain longer (up to 10 days). Clinical manifestations of both forms of a mountain disease generally match.

Acute mountain disease.

Easy degree.

Symptoms of easy degree of a mountain disease appear within 6 — 12 hours (and sometimes earlier) after rise on new height. At bigger height its symptoms are found earlier. At many they are shown in deterioration in health, some slackness in the beginning. The beginner feels at first in mountains an indisposition, a cardiopalmus, slight dizziness, a small asthma at exercise stresses, drowsiness and at the same time badly fills up. In 3 — 4 days these phenomena if not to rise above, as a rule disappear. Accurate objective kliniko-neurologic symptoms of this form of a mountain disease do not exist.

All above-mentioned symptoms are not specific and can be a consequence of many other diseases. Nevertheless it is considered correct to assume an acute mountain disease if the head begins to hurt not acclimatized person who rose by height more than 2500 m and one of above-mentioned symptoms appears still at least. If the above described symptoms appear after 36 hours of good shape, then it is necessary to exclude existence of other disease.

Average degree.

At the heights of 2500 — 3500 m at some people it can be observed euphoria signs: high spirits, excessive gesticulation and garrulity, the accelerated tempo of speech, causeless fun and laughter, the carefree, lightweight relation to the environment. Further the euphoric state is replaced by decline of mood, apathy, melancholiness, interest in surrounding becomes dull.

At the heights of 4000 — 5000 m the health worsens. Moderate and even severe headache develops. The dream becomes uneasy, alarming, with unpleasant dreams, some fall asleep hardly and often wake up from feeling of suffocation (periodic breathing). At physical efforts breath and heartbeat become frequent at once, dizziness develops. Appetite goes down, there is nausea which happens intensive and can pass into vomiting. Taste changes: there is a wish for preferential acid, spicy or salty food (that partly is explained by dehydration and disturbance of water-salt balance). Dryness in a throat causes thirst. Bleedings from a nose are possible.

Heavy degree.

At the heights of 5000 — 7000 m and the health seldom is higher happens good, it is more often unsatisfactory. The general weakness, fatigue, weight in all body is felt. Also severe pain in temples, a frontal, occipital part of the head does not stop moderate, and sometimes. At the sharp movements and inclinations or after work there is dizziness. The person falls asleep with great difficulty, often wakens, some suffer from sleeplessness. The diseased with a mountain disease is not capable is long to carry out an exercise stress because of an asthma ("breath of the tired-out dog"), and heartbeat, working capacity falls, for example at the height of 8000 m there are 15 — 16% of working capacity from made at sea level height.

Dryness in a throat increases, all the time getting thirsty. Language is laid over. Many are disturbed by dry cough. Appetite is, as a rule, lowered or is absent. The number of cases of nausea and vomiting at meal increases. Pains in a stomach and gastrointestinal frustration, abdominal distention are often noted. The respiratory rhythm during a night dream is broken (Cheyna-Stokes's breath). Integuments of the person, especially lips, get pale, the shade as a result of insufficient saturation by oxygen of an arterial blood which loses the scarlet color is more often cyanotic. Temperature increases on 1 — 2 of C, there is a fever. Cases of bleedings from a nose, a mouth, lungs (blood spitting), sometimes gastric become frequent.

Under certain conditions, since 4000 m there can be dangerous forms of a mountain disease caused by failure of adaptable mechanisms and development of more serious pathologies: the fluid lungs also swelled a brain.

Mountain fluid lungs.

Against the background of severe forms of an acute mountain disease, and sometimes suddenly, blood developments of stagnation in a small circle of blood circulation and a fluid lungs, and also an acute heart failure can develop.

Symptoms of a mountain fluid lungs, as a rule, appear for 2 — 3 day of stay at big height. Capillaries of lungs come out liquid which, getting to a gleam of alveoluses, prevents gas exchange, as a result the hypoxia amplifies and the disease progresses. If not to take a measure, from the first emergence of symptoms to death from suffocation there can pass few hours. Its development is promoted by the diseases of a respiratory organs and blood circulation postponed earlier, chronic or acute respiratory infection (for example quinsy, bronchitis, pneumonia, chronic purulent dental diseases), the excessive exercise stresses which are carried out before there occurred steady adaptation.

The high-rise fluid lungs from all diseases, specific to mountains, is the most frequent cause of death. At the height of 2700 m the frequency of a mountain fluid lungs makes 0,0001% and increases to 2% for 4000 m.

In development of a mountain fluid lungs distinguish 3 stages:

First stage.

Proceeds against the background of symptoms of heavy degree of an acute mountain disease:
the patient stands on the feet, but independently does not move;
lack of urine more than 8 — 10 h;
symptoms of oppression of a respiratory center — the speeded-up pulse and breath are observed, it is difficult to cough, nose wings participate in breath in the beginning, teeth are clenched;
fever, fever;
skin is wet, pale;
cyanosis: cyanotic nails, lips, nose, ears.

The following specific symptoms are also characteristic of a fluid lungs:
dry tussiculation, sadneniye in a throat;
complaints are one squeezing lower than a breast, retrosternal pains;
symptom of "vanki-vstanka": because of weakness of the patient tries to lie, but because of suffocation is forced to sit down;
Temperature is 38 — 39 °C. If the fluid lungs develops without pneumonia, then temperature can make 36 — 37 °C.

Second stage.

Usually in 8 — 12 h after the first symptoms there comes the second stage of a fluid lungs:
the patient is already not necessary standing;
cough with a foamy phlegm;
the pulse which is speeded up arterial pressure constantly rises;
breath is noisy, when listening rattles are heard;
symptom of "vanki-vstanka" or semi-sitting position;
thirst.

Third stage.

Develops in 6 — 8 h and for 4 — 8 h till a lethal outcome:
symptoms of considerable dehydration: thirst amplifies;
the most severe headache;
temperature increase;
motive concern;
the rattles heard at distance;
bloody phlegm, pink foam from a nose and a mouth;
suffocation;
arrhythmia, pressure can reach 150 — 170/90 — 100.

Without appropriate treatment there is a pressure drop, a collapse, a coma, a cardiac standstill.

Mountainous swelled a brain.

High-rise wet brain can be considered as extreme manifestation of an acute mountain disease. Capillaries of a brain come out liquid, it increases in volume. At the same time tissues of a cerebellum put in a trunk of a spinal cord, there is a destruction of the vital centers which are in it and there comes death.


Distinguish 3 stages of hypostasis of a brain:

First stage.

Proceeds against the background of symptoms of heavy degree of an acute mountain disease:
the patient stands on the feet, but independently does not move;
lack of urine more than 8 — 10 h;
symptoms of oppression of a respiratory center — the speeded-up pulse and breath are observed, it is difficult to cough, nose wings participate in breath in the beginning, teeth are clenched;
fever, fever;
skin is wet, pale;
cyanosis: cyanotic nails, lips, nose, ears.

Because of changes in a brain specific symptoms appear:
the head is poured by lead, noise in the head, headaches of arching character;
increase of vomiting;
lack of coordination (ataxy): gait as, however, and in general behavior of the patient most of all remind alcohol intoxication, the person cannot, without being unsteady, to pass in a straight line;
slackness, drowsiness, dispassionateness, apathy;
the patient satisfies requests under control and right there stops performance to a repeated reminder;
unlike a fluid lungs of the patient can lie.

Second stage.

Usually in 8 — 12 h after emergence of the first symptoms there comes the second stage of hypostasis of a brain:
strengthening of headaches, sleeplessness, thirst;
alalias;
changes in behavior: the person stops being similar to himself, irrational behavior (aggression, attempt to suicide), And the patient can not understand that happens to it and to actively resist attempts of to lower, staying in a condition of euphoria, to be torn up;
oglushyonnost, block, dispassionateness, apathy;
changes of pupils: expansion, disappearance of light reaction, fixing of a look, asymmetry.

Third stage.

Through 6 — 8 more and for 4 — 8 h till a lethal outcome there comes the third stage:
symptoms of considerable dehydration: thirst;
the headache amplifies;
temperature increase;
motive concern;
strengthening of changes in pupils, eyeground phlebectasia;
numbness of extremities;
consciousness oppression, oglushyonnost, block, the victim becomes sluggish, sleepy, answers questions in monosyllables and not at once, can be disoriented in a surrounding situation.

At the end of the third stage there is a loss of consciousness, an apnoea and cordial activity.

Treatment of a hypobaropathy:

Easy and average degree.

It is necessary to emphasize that easy degree of a mountain disease, despite unpleasant feelings, usually only the state which is physically limiting the person without any long effects. Bases of treatment of easy manifestations of a mountain disease:
Rest;
Liquids (juice, teas);
Weak analgetics (aspirin, ibuprofen, paracetamol);
medicines from nausea (Aeronum, acid fruit — apples, oranges, lemons, dried apricots) and vomitings (intramuscular introduction of Metoclopramidum (raglan));
If necessary to appoint acetazoleamide of 125 — 250 mg twice a day within 3 days.

At favorable combination of circumstances, symptoms usually pass after 2-4 days.

Heavy degree.
The most efficient method of treatment is descent of the victim down. It is necessary to use completely any possibility of independent movement of the victim which does not allow to develop apathy, to indifference and overcooling.
In extreme cases it is necessary to use an oxygen mask (better in mix with carbon dioxide: O2 + 5-7% of CO2). Use of the portable hyperbaric pressure chamber (compression chamber) representing a tight bag in which the manual pump or the compressor forces air is effective.
Acetazoleamide of 125 — 250 mg twice a day within 3 days.
Dexamethasone of 8 mg orally, further to 4 mg is each 6 hours within a day.
It is necessary to lower febrifugal drugs temperature to 37 °C.
It is not necessary to use narcotic analgetics (Promedolum, morphine) and alcohol.

Treatment of a fluid lungs.
The major method of controlling with a fluid lungs is immediate descent down. Descent even on several hundred meters can lead to improvement of a state.
Use of the portable hyperbaric camera is effective. In extreme cases it is necessary to use an oxygen mask.
The victim needs to give a semi-sitting position.
If systolic arterial pressure ("upper") more than 90 mm of mercury., intramusculary it is necessary to enter 2-3 ampoules of furosemide.
For prevention and treatment of a mountain fluid lungs nifedipine is effective (10 mg inside in the beginning, then 20 mg of nifedipine of slow release each 12 hours).
To put Tabulettae Nitroglycerini under language (with a systolic arterial pressure more than 90 mm of mercury.). Repeatedly nitroglycerine can be given in 20 min. no more than 3 times.
To impose venous plaits on hips so that below the place of their imposing pulse on arteries was probed. It will create depot of blood in the lower extremities and will prevent its return to heart. However, this method should be applied only during bystry descent of the victim down to win a little time. In one or one and a half hours plaits should be removed, and sharp inflow of blood to the heart which is tired out with a hypoxia can cause an acute heart failure.
At an opportunity it is necessary to enter Aminophyllinum intravenously (10 ml. 2,4% in 100 ml. isotonic solution).
If at the patient the pink foamy phlegm — breath through the gauze moistened with alcohol for decrease in foaming in air cells is obviously allocated.

At stationary conditions when preservation of consciousness does not play a role, it is necessary to apply morphine, it reduces pulmonary pressure.

Important: it is necessary to know that no medicamentous manipulations should serve as a delay for descent down.

The fluid lungs very quickly can develop against the background of inflammatory respiratory diseases (quinsy, pneumonia) therefore at emergence of their signs of the person it is necessary to lower, at the same time giving symptomatic medicamentous help.

Treatment of hypostasis of a brain.
At emergence of symptoms of mountain wet brain it is necessary to begin descent immediately. The delay can lead to death of the patient. If symptoms appeared in the evening, it is impossible to wait with descent till the morning. It is necessary to evacuate at least up to that height at which the person last time well felt, and it is up to 2500 m better. As a rule if in time to begin descent, symptoms quickly and completely disappear.
It is necessary to begin oxygen supply.

Drugs at hypostasis of a brain play rather supporting role, but, nevertheless, and you should not neglect them. Apply dexamethasone to reduction of symptoms and simplification of evacuation (8 mg in the beginning, then on 4 mg each 6 hours inside or parenterally).

It is not necessary to apply at brain hypostasis as vasodilating (nitroglycerine, nifedipine, trental), and the drugs increasing pressure (caffeine, adrenaline): any increase in pressure or vasodilatation will strengthen wet brain. Now also do not recommend to use diuretic drugs.

Disappearance of symptoms happens not right after descent, and the patient has to be transferred under observation of health workers.