Three phenomena occur in the airways of patients with asthma:
1. Decreased bronchial diameter, which restricts air flow.
2. Inflammation, with increased thickness of the bronchial wall, which also contributes to restricting air flow.
3. Increased activity in the glands that produce mucus, with increased secretions contributing further to breathing difficulty.
Cells that circulate in the blood are involved in the local inflammation observed in asthma: T lymphocytes, mast cells and eosinophils. These cells are responsible for the body’s normal defence and their activity is increased in asthma. Medication for asthma attempts to regulate this activity.
According to the degree of restriction, the person affected will experience breathing difficulty and a sensation of lack of air. Also characteristic of asthma are wheezing, which is the sharp whistle-like sound of the air as it passes through the smaller airways, and increased bronchial secretion.
How is affected by the condition?
Asthma can affect all age groups and sometimes overlaps with bronchitis. On many occasions it can be allergic in origin or come as a result of exposure to an environmental or chemical agent.
Spirometry, chest x-ray, allergy tests.
Some basic questions for diagnosis:
1) Have you ever had a whistling sound in your chest?
2) Have you been coughing, especially at night?
3) Have you had a cough, whistling sound, difficulty breathing at some times of the year or in contact with animals, plants, tobacco or whilst at work or after exercise?
4) Have you had colds that last more than 10 days or are "chesty"?
5) Have you used inhaled medication?
Treatment is based on using bronchodilators, in the form of an inhaler or tablets. Anti-inflammatory drugs also have an important role.
The most common diagnostic tests for asthma are based on:
1) Spirometry: Measures air flow on inhaling and exhaling and detects any restrictions in the airway, one of the characteristics of asthma.
2) Bronchodilator test: Tests if spirometry improves with drugs to dilate the airway.
3) Bronchial challenge test, the same test in the opposite direction with drugs that cause a slight airway obstruction, detected by spirometry.
To prevent asthma, it is fundamental not to smoke and avoid exposure to allergens that precipitate it, which are detected with the allergy tests that form part of the asthma exam.
Hospital o serveis complementaris relacionats
De Souza Galvão