Asthma

Respiratory organs

The nose - which is to moisten, heat, and clean tha air -, larynx, pharynx, windpipe - which branches out to bronchial tubes -, bronchial and the lung are the parts of of the respiratory organs. The lungs consist of air sacks (alveoles). The channels leading here are covered with mucous membrane.

The nose is the first organ the air must cross. Its task is to heat the air to body temperature, to fill it completely with moisture, and to filter it e.g. from pollen. That is why hay-fever mainly afflict the nose. Besides these it has many tasks in smelling and tasting. All functions of the nasal cavity has not been explored yet.

The system of bronchial tubes is a tree-like tube system which brings the inhaled air to the alveoles. From the windpipe a bronchus branches out to both sides and these branch out to three further branches to the right and two ot the left. The total cross-section of the respiratory system increases which almost completely stops the turnback of the air. Whirlwind can only come into being at fast breathing or morbid alteration of the respiratory system.

The smallest bronchial tubes are not stabilized by cartilage rings like the bigger ones. So at intensive enviromental pressure ( e.g. when we try tu breath out with muscle power) these small bronchials can easily collaps.

The width of the respiratory system is controlled by the muscles. These are controlled by nerves which belong to the autonomic nerve system. That is why two nerves play an important role: vagus-nerve which causes the contraction and the sympathetic nerve which causes the atony of the muscles.

The change of the gases takes plece on the walls of the alveoles. Red blood cells bind oxigen; carbon combinations turn into carbon dioxide which we breath out. Breathing is controlled by the brain and happens automatically. Irregular function of the bronchial tubes and the alveoles can lead to laboured breathing or irregular airflowing. For these occasions our body developed many protection methodes. It protects the tubes from beeing stopped with chemical processes and the movement of the muscles.

What is asthma?

Asthma is a widespread disease - all over the world. The most frequent disease in childhood is asthma. Twice as much boys have to face this disease than girls, but among adults there are one and a half times more woman patients then man.

The scientific definition of asthma is the following: 'Asthma is a varying and reversible disease, inflammination and hyperactivity of the respiratory system because of stopped respiratory tubes.'

Besides asthma ther is two oder diseases which have similar effects: chronic bronchitis and pulmonary emphysema. Asthma is different because of the attacks which always exests at least during the first year. Chronic bronchitisstarts with seemingly not serious symptoms: cough and discharge. Laboured breathing comes later - but then there is no pause between the attacks. At emphysema because of the atrophy of the tissue more air get into the lungs. Also here can (mainly when the body is overloaded) we meet laboured breathing. Besides it can be result of the asthma or chronic bronchitis.

Asthma was known in the acient times (Hippokrates). It can have more reasons. Heritable, genetically bound or recieved, unusually high sensitivity and reaction-ability with the system of bronchial tubes which appears as exaggerated inclination to contracion of muscles.

The hypersensitivity of the system of bronchial tubes plays one of the most important roles in asthma because it produces the asthma reaction. It can be produced many ways (herited, becoming infected depending on the surroundings etc.). It often goes together with the inflammination of the mucous membrane of the bronchus.

How does the lung alter in case of asthma?

The contraction of muscles has great importance at asthma. It was not taken seriously because after death it cannot be shown. It leads to laboured breathing though with medicine it can be relatively easily and quickly influenced. Another factor that the tubes get filled with discharge which hinders the air to get out. With muscle power the the confusion can be compenseted; because exhaling happens automatically because of the elasticity of the tissue laboured bgeathing appears here first. In most cases this laboured breathing is not the result of irregular change of gases because (except from extreme cases) it can be compensated with the body.

Asthma and allergy

Asthma and allergy seems to belong to each oder inseparably. In reality not all asthma diseases are allergic.

If an allergen gets into the body immediately socalled IgE antibody is produced. As a result of the confrontation of these two this inflammination-causing material flows out on the membrane of the cells. To this come the following factores: musclepower, tissue-fluidity and increased ammount of discharge. Normally they are important elements of the immun system. In case of allergy, however, they have the opposite effect.

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