Bronchial asthma is a chronic non–infectious disease of the respiratory tract of an inflammatory nature. An attack of bronchial asthma often develops after the precursors and is characterized by a short sharp inhalation and a noisy long exhalation. It is usually accompanied by a cough with viscous sputum and loud wheezing. Diagnostic methods include evaluation of spirometry, peak flowmetry, allergy tests, clinical and immunological blood tests. Aerosol beta-adrenomimetics, m-cholinolytics, ASIT are used in the treatment, glucocorticosteroids are used in severe forms of the disease.
Meaning
Over the past two decades, the incidence of bronchial asthma (BA) has increased, and today there are about 300 million asthmatics in the world. This is one of the most common chronic diseases to which all people are susceptible, regardless of gender and age. Mortality among patients with bronchial asthma is quite high. The fact that in the last twenty years the incidence of bronchial asthma in children has been constantly growing, makes bronchial asthma not just a disease, but a social problem, to combat which maximum efforts are directed. Despite the complexity, bronchial asthma responds well to treatment, thanks to which it is possible to achieve a stable and long-term remission. Constant monitoring of their condition allows patients to completely prevent the onset of attacks of suffocation, reduce or eliminate the use of medications to stop seizures, as well as lead an active lifestyle. This helps to maintain lung function and completely eliminate the risk of complications.
Bronchial asthma causes
The most dangerous provoking factors for the development of bronchial asthma are exogenous allergens, laboratory tests for which confirm a high level of sensitivity in patients with asthma and in persons who are at risk. The most common allergens are household allergens – these are household and book dust, food for aquarium fish and animal dandruff, allergens of plant origin and food allergens, which are also called nutritive. In 20-40% of patients with bronchial asthma, a similar reaction to medications is detected, and in 2% the disease is obtained as a result of working in harmful production or, for example, in perfume stores.
Infectious factors are also an important link in the etiopathogenesis of bronchial asthma, since microorganisms, their waste products can act as allergens, causing sensitization of the body. In addition, constant contact with infection supports the inflammatory process of the bronchial tree in the active phase, which increases the sensitivity of the body to exogenous allergens. The so-called haptenic allergens, that is, allergens of a non-protein structure, entering the human body and binding with its proteins also provoke allergic attacks and increase the likelihood of AD. Factors such as hypothermia, burdened heredity and stressful conditions also occupy one of the important places in the etiology of bronchial asthma.
Pathogenesis
Chronic inflammatory processes in the respiratory organs lead to their hyperactivity, as a result of which, upon contact with allergens or irritants, bronchial obstruction instantly develops, which limits the air flow rate and causes suffocation. Attacks of suffocation are observed with different frequency, but even in remission, the inflammatory process in the respiratory tract persists. At the heart of the violation of the patency of the air flow in bronchial asthma are the following components: obstruction of the respiratory tract due to spasms of the smooth muscles of the bronchi or due to swelling of their mucous membrane; blockage of the bronchi with the secret of the submucosal glands of the respiratory tract due to their hyperfunction; replacement of the muscle tissue of the bronchi with connective tissue during the long course of the disease, which causes sclerotic changes in the bronchial wall.
The changes in the bronchi are based on the sensitization of the body, when, with allergic reactions of an immediate type, occurring in the form of anaphylaxis, antibodies are produced, and upon repeated encounter with the allergen, an instantaneous release of histamine occurs, which leads to edema of the bronchial mucosa and to hypersecretion of the glands. Immunocomplex allergic reactions and delayed sensitivity reactions proceed similarly, but with less pronounced symptoms. The increased amount of calcium ions in the human blood has also recently been considered as a predisposing factor, since excess calcium can provoke spasms, including spasms of the bronchial muscles.
In the pathoanatomic examination of the deceased during an attack of suffocation, there is a complete or partial blockage of the bronchi with viscous thick mucus and emphysematous expansion of the lungs due to difficulty exhaling. Tissue microscopy most often has a similar picture – it is a thickened muscle layer, hypertrophied bronchial glands, infiltrative bronchial walls with desquamation of the epithelium.
Classification
BA is divided by etiology, severity of the course, level of control and other parameters. By origin, allergic (including occupational asthma), non-allergic (including aspirin asthma), unspecified, mixed bronchial asthma are distinguished. According to the severity, the following forms of BA are distinguished:
1 Intermittent (episodic). Symptoms occur less than once a week, exacerbations are rare and short.
2 Persistent (constant flow). It is divided into 3 degrees:
- mild – symptoms occur from 1 time a week to 1 time a month
- average – frequency of seizures daily
- severe – symptoms persist almost constantly.
During asthma, exacerbations and remission (unstable or stable) are isolated. If possible, the control of the BA can be controlled, partially controlled and uncontrolled. The complete diagnosis of a patient with bronchial asthma includes all of the above characteristics. For example, “Bronchial asthma of non-allergic origin, intermittent, controlled, in stable remission.”
Bronchial asthma symptoms
An attack of suffocation with bronchial asthma is divided into three periods: the period of precursors, the period of peak and the period of reverse development. The period of harbingers is most pronounced in patients with infectious and allergic nature of asthma, it is manifested by vasomotor reactions from the nasopharyngeal organs (abundant watery discharge, incessant sneezing). The second period (it can start suddenly) is characterized by a feeling of tightness in the chest, which does not allow breathing freely. The inhalation becomes sharp and short, and the exhalation, on the contrary, long and noisy. Breathing is accompanied by loud wheezing wheezes, a cough with viscous, difficult to expectorate sputum appears, which makes breathing arrhythmic.
During an attack, the patient’s position is forced, usually he tries to take a sitting position with his body tilted forward, and find a fulcrum or rests his elbows on his knees. The face becomes puffy, and during exhalation, the cervical veins swell. Depending on the severity of the attack, you can observe the participation of muscles that help overcome resistance on exhalation. In the period of reverse development, a gradual discharge of sputum begins, the number of wheezes decreases, and the attack of suffocation gradually fades.
Manifestations in which the presence of bronchial asthma can be suspected.
- high-pitched wheezing when exhaling, especially in children.
- recurring episodes of wheezing, difficulty breathing, chest tightness and coughing, which increases at night.
- seasonality of deterioration of well-being on the part of the respiratory system
- the presence of eczema, allergic diseases in the anamnesis.
- deterioration or occurrence of symptoms in contact with allergens, taking medications, in contact with smoke, with sudden changes in ambient temperature, acute respiratory infections, physical exertion and emotional stress.
- frequent colds “descending” into the lower respiratory tract.
- improvement of the condition after taking antihistamines and anti-asthmatic drugs.
Complications
Depending on the severity and intensity of the attacks of suffocation, bronchial asthma can be complicated by emphysema of the lungs and the subsequent addition of secondary cardiopulmonary insufficiency. An overdose of beta-adrenostimulants or a rapid decrease in the dosage of glucocorticosteroids, as well as contact with a massive dose of allergen can lead to an asthmatic status, when attacks of suffocation come one after another and it is almost impossible to stop them. Asthmatic status can be fatal.
Diagnostics
The diagnosis is usually made by a pulmonologist clinician based on complaints and the presence of characteristic symptoms. All other research methods are aimed at establishing the severity and etiology of the disease. With percussion, the sound is clear boxed due to the hyper-airiness of the lungs, the mobility of the lungs is sharply limited, and their boundaries are shifted downwards. During auscultation, vesicular breathing is heard above the lungs, weakened with an elongated exhalation and with a large number of dry wheezing wheezes. Due to the increase in lung volume, the point of absolute dullness of the heart decreases, the heart tones are muted with the accent of the second tone over the pulmonary artery. From instrumental studies conducted:
- Spirometry. Spirography helps to assess the degree of bronchial obstruction, to find out the variability and reversibility of obstruction, as well as to confirm the diagnosis. With BA, forced exhalation after inhalation with a bronchodilator increases by 12% (200 ml) or more in 1 second. But to obtain more accurate information, spirometry should be performed several times.
- Peak flowmetry. Measurement of peak expiratory activity (PEA) allows monitoring the patient’s condition, comparing the indicators with those obtained earlier. An increase in PEA after inhalation of bronchodilator by 20% or more from PEA before inhalation clearly indicates the presence of bronchial asthma.
Additional diagnostics include allergen tests, ECG, bronchoscopy and lung x-ray. Laboratory blood tests are of great importance in confirming the allergic nature of bronchial asthma, as well as for monitoring the effectiveness of treatment.
- Blood test. Changes in the blood test – eosinophilia and a slight increase in ESR – are determined only during the period of exacerbation. Assessment of the blood gas composition is necessary during an attack to assess the severity of DN. A biochemical blood test is not the main diagnostic method, since the changes are general in nature and such studies are prescribed to monitor the patient’s condition during an exacerbation.
- Sputum analysis. Microscopy in sputum can detect a large number of eosinophils, Charcot-Leyden crystals (shiny transparent crystals formed after the destruction of eosinophils and shaped like rhombuses or octahedra), Curschmann spirals (formed due to small spastic contractions of the bronchi and look like casts of transparent mucus in the form of spirals). Neutral leukocytes can be found in patients with infection-dependent bronchial asthma at the stage of an active inflammatory process. It is also noted that Creole bodies are isolated during an attack – these are rounded formations consisting of epithelial cells.
- Study of the immune status. With bronchial asthma, the number and activity of T-suppressors decreases sharply, and the amount of immunoglobulins in the blood increases. The use of tests to determine the amount of immunoglobulin E is important if it is not possible to conduct allergological tests.
Bronchial asthma treatment
Since bronchial asthma is a chronic disease regardless of the frequency of attacks, the fundamental point in therapy is the exclusion of contact with possible allergens, compliance with elimination diets and rational employment. If it is possible to identify an allergen, then specific hyposensitizing therapy helps to reduce the body’s reaction to it.
To stop attacks of suffocation, beta-adrenomimetics are used in the form of an aerosol, in order to quickly increase the lumen of the bronchi and improve the outflow of sputum. These are phenoterol hydrobromide, salbutamol, orciprenaline. The dose in each case is selected individually. Preparations of the m-cholinolytic group – aerosols of ipratropium bromide and its combination with phenoterol also stop seizures well.
Xanthine derivatives are very popular among patients with bronchial asthma. They are prescribed to prevent attacks of suffocation in the form of tablet forms of prolonged action. In the last few years, drugs that prevent the degranulation of mast cells have had a positive effect in the treatment of bronchial asthma. These are ketotifen, sodium cromoglycate and calcium ion antagonists.
In the treatment of severe forms of AD, hormonal therapy is connected, almost a quarter of patients need glucocorticosteroids, 15-20 mg of Prednisone is taken in the morning together with antacid drugs that protect the gastric mucosa. In a hospital setting, hormonal drugs can be prescribed in the form of injections. The peculiarity of the treatment of bronchial asthma is that it is necessary to use medications in the minimum effective dose and achieve an even greater reduction in dosages. Expectorant and mucolytic drugs are indicated for better sputum discharge.
Prognosis and prevention
The course of bronchial asthma consists of a series of exacerbations and remissions, with timely detection, it is possible to achieve a stable and long-term remission, the prognosis depends more on how carefully the patient treats his health and follows the doctor’s instructions. Prevention of bronchial asthma is of great importance, which consists in the rehabilitation of foci of chronic infection, the fight against smoking, as well as in minimizing contacts with allergens. This is especially important for people who are at risk or have a burdened heredity.