What is Asthma?
Bronchial asthma is a chronic inflammatory respiratory tract disease, manifested in dyspnea attacks, which often is accompanied by cough and can transfer into asthma attack. This happens due to the fact that airways excessively respond to different stimuli. In response to irritation they constrict and produce large amounts of mucus that disrupts normal air flow during breathing.
Asthma occurs among people of all ages, but most often it manifests itself at children – later half of them «outgrow» their illness. Now more than 300 million people in the world suffer from this disease and their number is constantly increasing.
Due to high asthma prevalence, its ability to reduce work capacity and cause disability, there are many global and national programs dedicated to fight against this disease. For example, in the UK about a billion pounds sterling is invested for such programs a year. At World Health Organization (WHO) initiative on 4 May the World Asthma Day is organized each year.
Chronic inflammation, which occurs at patients with bronchial asthma makes airways sensitive to allergens, chemical irritants, tobacco smoke, etc. At their effect there occur edema and bronchospasm, at this moment bronchial mucus is produced in large amounts. This obstructs normal air passage through airways during breathing.
Depending on asthma attack cause there distinguish asthma types with predominance of allergic component and non-allergic asthma.
Indication, that asthma is allergic, is that exacerbations occur at contact with certain allergens (pollen, fur, house dust, certain foods), they are seasonal. Allergic asthma attack at humans is often accompanied by runny nose, vegetative dystonia symptoms, urticaria fever.
At non-allergic asthma chronically inflamed airways are hypersensitive. Any irritation causes bronchospasm, and air flow through them is limited, which leads to coughing and asthma attacks.
There are many causes for asthma attack. For example, acrid odor – cigarette smoke, household chemicals, soaps, perfumes, exhaust fumes and others. Researchers around the world have come to disappointing conclusion that one out of five asthmatics owes his disease to his profession.
- Asthma symptoms can also occur within a few minutes after physical exercise – it may be, for example, exercises, connected with inhalation of cold, dry air – such as running outdoors in winter. In such cases we speak about exercise-induced asthma.
- Attack that occurs when taking aspirin or other anti-inflammatory drugs indicates the so-called aspirin-induced asthma.
- Asthma cause, triggered by nutritional supplements, may be, for example, sulphites reception (beer, wine preservatives).
- If attack appears both at contact with allergen, and when exposed to other factors, this type is called mixed asthma. That is, this is the most common form, especially in the later stages of the disease.
- In cases when asthma attack has no clear reasons, it is called unspecified.
At severe or acute asthma people during attack breathe through mouth, using, for easier breathing through narrowed airways, shoulders, neck and corpus musculature. Furthermore, when airways are constricted, inhale appears easier than exhale. This happens because inhale is a procedure familiar to our body and chest muscles are trained to perform this action.
Exhale, in contrast, normally occurs passively, i. e. without special effort, so muscles are not developed enough to remove air through narrowed airways. As a result, air remains in lungs and they become swollen.
By the way, young people suffering from asthma for a long time, precisely because of this acquire the so-called «pigeon breast». At severe acute asthma, previously «whistling» chest can become «silent», without whistling sounds. This is due to the fact that amount of inhaled and exhaled air is so small that the sound can not be heard.
Exercise-Induced Asthma
Often in medical practice there occurs such disease as exercise-induced asthma. This disease affects both adult men and women, and children. Prevalence in adult population ranges from 2 to 7%. As for children, this figure is closer to 10%. As in was said above asthma is a respiratory tract chronic disease, caused by bronchial mucosa increased sensitivity to various irritants. Against this background, there is a narrowing of bronchi lumen, leading to lung ventilation disruption. At asthma patients experience recurrent breathlessness attacks. Currently, very often there is diagnosed asthma, which symptoms appear on the background of physical exercise. What is etiology, clinical features and treatment of exercise-induced asthma?
Asthma Specifics
Suffocation is the main disease manifestation. At simplest asthma form, suffocation attack can be triggered by the following factors:
- taking medication (NSAIDs);
- inhaling dust;
- inhaling fungi;
- contact with animal hair;
- acrid odor;
- low environmental temperature.
Exercise-induced asthma attack occurs as a result of bronchospasm on the background of physical activity. This can be jogging, brisk walking, various sports. Attack may occur during exercise or after a short period of time. This pathology is most often diagnosed at young people. Contributing factors to this form of asthma development are:
- presence of viral infection;
- overtention;
- genetic predisposition;
- smoking;
- cold or dry air effects on the body.
At healthy people, bronchoconstriction and dyspnea after physical exercise can also be observed, but this is a temporary condition. It is another thing, if a person was diagnosed asthma, and attacks occur after physical exercise.
Disease Pathogenesis
Asthma developing mechanism is same for children and adults. At the heart of symptoms onset is bronchial hyperreactivity. This is increased bronchi reaction to various influences. This reactivity appears because of autonomic nervous system disorders. An important role in obstruction development is played by inflammation mediators. At asthma bronchoconstriction is periodic. At the same time, resistance to incoming air in respiratory tract increases, there is a hyperextension of lung tissue. All this causes decrease in blood oxygen saturation and ventilation violations. At bronchial asthma various cells are activated (macrophages, eosinophils, mast cells, T-lymphocytes).
Attack developing mechanism on the background of physical activity is not fully understood. There is a theory that attack is triggered by drying and cooling of airway mucosa. This explains the fact that inhalation of warm and humid air during attack improves patient’s condition. Furthermore, during research it was found that physical exercise after the first asthma attack often leads to respiratory dysfunction.
Clinical Manifestations
Symptoms of exercise-induced asthma are few. At the beginning dyspnea disappears after resting for 30 – 40 minutes. Then cupping requires medication, that dilates bronchi. The main asthma symptoms are:
- paroxysmal cough;
- dyspnea;
- feeling of lack of oxygen;
- wheezing when breathing or coughing.
During attack, patients often complain on lack of air. Often these people take forced posture (sitting, leaning forward). At bronchial exercise-induced asthma, as well as other forms of this disease, there is dyspnea of expiratory type. A man quickly inhales and slowly exhales. Often patients observe chest pains. At breathing wheezing is determined.
Sometimes catarrhal symptoms, sneezing, coughing appear before attack. Cough is dry or characterized by small amount of sputum release. In contrast to typical asthma form, cough is prolonged at exercise-induced asthma. It disappears on its own within 30 – 40 minutes. In severe cases, cyanosis may occur at patients with severe bronchospasm. This indicates severe respiratory insufficiency.
Diagnostic Measures
To identify exercise-induced asthma careful examination of the patient is required.
The main method of exercise-induced asthma diagnosis is running test. This is functional exercise test. Obstruction can occur any time after the load (2, 5, 8 minutes). Attack is expressed in dyspnea and inability to perform exercise. Instead of running there can be used bicycle ergometry or step-test. Dyspnea is a subjective symptom. Accurate diagnosis requires objective criteria, so immediately after patient’s condition worsening there is conducted study of respiratory function. Doctor should assess forced expiratory volume, peak expiratory flow rate, peak flow rate.
Additional methods of disease diagnosis are:
- medical anamnesis and disease history;
- visual examination;
- lungs auscultation;
- allergy tests;
- blood test;
- sputum test;
- peakflowmetry;
- spirometry;
- X-ray lungs examination;
- drug tests with bronchodilators.
During patient examination it is very important to clarify asthma attacks connection to physical exercise. Lungs auscultation reveals non-specific signs of obstruction (hard breathing, wheezing). Wheezing can be heard without stethoscope. Often, they are strong and whistling. Blood can contain immunoglobulins E, allergic reaction symptoms.
Treatment
Treatment of this disease has some peculiarities. Patients should avoid excessive physical exercise. This is necessary to prevent recurrent attacks. Bronchial asthma (read more) can not be cured completely. Treatment is aimed at preventing complications, preventing attacks and improve quality of patient’s life. Basic drugs, which are used consistently during attack-free interval, are:
- cromones;
- antileukotrienes;
- monoclonal antibodies.
In case of attack beta-adrenergic agonists are used (Ventolin, etc.). Drugs such as glucocorticosteroids for inhalation use are not always effective, therefore they are rarely used. This also applies to xanthines. For bronchospasm attack prevention medications can be taken before going out at cold weather, as bronchospasm provoking factor is inhalation of cold air. At cold weather you need to breathe only through your nose. In nasal cavity air masses are moistened and warmed, which reduces attack possibility.
«Load Dosage»
An important aspect of treatment is attack prevention. This is achieved by dosing physical load. The following sports are best tolerated by patients: volleyball, gymnastics, baseball, wrestling. These sports provide muscle tension and relaxation periods of short duration, alternating with each other. Complete rejection from physical activity is not allowed, as hypodynamia is a triggering factor for many other diseases development, in particular, cardiovascular, gastrointestinal tract.
Swimming is well tolerated by patients with asthma. Patients with asthma are recommended those kinds of physical activity, which are aimed at training respiratory muscles. This may be inflating balloons, diaphragmatic breathing. Persons with increased allergic background are required to avoid physical stress during blossom period and temperature drops. Thus, exercise-induced asthma is diagnosed very often. At first symptoms of the disease you need to see a doctor and get tested to detect other respiratory diseases.