Asthma is a chronic inflammatory process that occurs in the respiratory tract, primarily in the bronchi, that is ,the “ducts” that bring air to the alveoli. Chronic inflammation provokes obstruction, that is, restriction (obstruction) of the passage of air through the bronchi and hypersensitivity of the bronchi to various stimuli. All this leads to the development of symptoms of bronchial asthma, that is, repeated episodes of wheezing, shortness of breath, a feeling of compression in the chest and coughing.
There are muscles in the wall of the bronchi, thanks to which the bronchi can change their diameter. In patients with asthma, the bronchi are “individually intolerant” – constricting too much and too often in response to stimuli (such as tobacco smoke, strong odors, exercise) that in a healthy person do not cause a reaction. Hypersensitivity of the bronchi causes dry cough attacks. Chronic inflammation also leads to edema of the bronchial wall and overproduction of mucus, bronchi are narrowed (t. Naz. obstruction of the bronchi). Bronchospasm causes shortness of breath and a feeling of compression in the chest. In patients with asthma, obstruction is usually reversible, after the application of appropriate treatment decreases significantly or disappears completely. However, in people who have not used inflammatory inhibitory treatment in the Airways for years, there is a constant remodeling and damage to the bronchial wall, in these patients, obstruction is irreversible.
Asthma symptoms occur spontaneously, especially at night or in the morning can also be caused by stress, nervous, accompany respiratory infections, appear after contact with allergens. There are several types of asthma, m.in.: allergic, non-allergic, aspirin or professional.
Asthma is diagnosed based on the above symptoms. An important element in establishing a diagnosis is the approval of allergic diseases in the patient, for example, allergic rhinitis, allergic conjunctivitis or manifestations of hypersensitivity to aspirin or factors to which the patient is exposed at work. An auxiliary study is a spirometric study (spirometry). In spirometrii estimates the volume of air exhaled and inhaled into the lungs during calm as well as exhaustive breathing. As part of the diagnosis of bronchial asthma performs. basal spirometry and spirometry after inhalation of a bronchodilator (called “obstruction reversibility assessment spirometry” or “diastolic test spirometry”). The spirometrii results are presented as a flow-volume curve graph, as well as a numerical form, i.e. an absolute value (volume in liters and flow in liters / minute) and a percentage of the proper values (allowable) for a person of a certain race, sex and height.
A change in the shape of the exhaust part of the flow-volume curve (flattening and elongation), abnormal values of the increased first-second expiratory volume (so-called FEV1 from the English term forced expiratory volume in one second), as well as a decrease in the result of the so-called tiffeneau test (factor FEV1 and FVC) are typical signs of obstruction in a spirometric study. An attempt at obstruction reversibility is used to assess whether obstruction is a permanent phenomenon or not. This study involves performing standard spirometry (without prior medication use) and then repeating the measurement after administration of a bronchial diastolic drug. The doctor describing spirometry checks whether the results of spirometry have significantly improved after the administration of a bronchial diastolic drug, the evaluation parameter is the FEV1 mentioned above.
To sum up, spirometry is used as an adjunct study for asthma recognition. Features of reversible bronchial obstruction in spirometry increase the likelihood of diagnosis. However, keep in mind that there are other diseases that cause similar changes in spirometry results. In addition, a typical feature of asthma is variable lung function. In the asymptomatic period, the result of spirometry can be quite normal, which does not exclude the diagnosis of asthma.
Auxiliary studies in the diagnosis of certain types of asthma are: point skin tests, measurement of serum concentrations of specific IgE (allergic asthma) or provocative tests with aspirin (aspirin asthma).