Chronic bronchitis is a diffuse progressive inflammatory process in the bronchi, leading to morphological restructuring of the bronchial wall and peribronchial tissue. Exacerbations occur several times a year and occur with increased cough, purulent sputum, shortness of breath, bronchial obstruction, subfebrility. Examination includes lung radiography, bronchoscopy, microscopic and bacteriological analysis of sputum, FVD, etc. In the treatment of chronic bronchitis, drug therapy (antibiotics, mucolytics, bronchodilators, immunomodulators), sanation bronchoscopy, oxygen therapy, physiotherapy (inhalation, massage, respiratory gymnastics, medicinal electrophoresis, etc.) is combined.
The incidence of chronic bronchitis among the adult population is 3-10%. Disease develops 2-3 times more often in men aged 40 years. Pathology in modern pulmonology is spoken of if for two years there have been exacerbations of the disease lasting at least 3 months, which are accompanied by a productive cough with sputum.
With a long-term course of pathology, the likelihood of diseases such as COPD, pneumosclerosis, emphysema of the lungs, pulmonary heart, bronchial asthma, bronchiectasis, lung cancer significantly increases. The inflammatory lesion of the bronchi is diffuse in nature and eventually leads to structural changes in the bronchial wall with the development of peribronchitis around it.
Causes of chronic bronchitis
Among the causes that cause the development of this disease, the leading role belongs to prolonged inhalation of pollutants – various chemical impurities contained in the air (tobacco smoke, dust, exhaust gases, toxic fumes, etc.). Toxic agents have an irritating effect on the mucous membrane, causing a restructuring of the secretory apparatus of the bronchi, hypersecretion of mucus, inflammatory and sclerotic changes in the bronchial wall. Quite often, acute bronchitis is transformed into chronic bronchitis untimely or not fully cured.
Exacerbation of chronic bronchitis, as a rule, occurs when a secondary infectious component (viral, bacterial, fungal, parasitic) is attached. Persons suffering from chronic inflammation of the upper respiratory tract are predisposed to the development of disease:
Non-infectious factors that cause exacerbation of disease may be arrhythmias, chronic heart failure, PE, gastroesophageal reflux disease, a1-antitrypsin deficiency, etc.
The mechanism of development of chronic bronchitis is based on damage to various parts of the system of local bronchopulmonary protection: mucociliary clearance, local cellular and humoral immunity (the drainage function of the bronchi is disrupted; activity of a1-antitrypsin decreases; production of interferon, lysozyme, IgA, pulmonary surfactant decreases; phagocytic activity of alveolar macrophages and neutrophils is inhibited).
This leads to the development of a classic pathological triad: hypercrinium (hyperfunction of the bronchial glands with the formation of a large amount of mucus), dyscrinium (increased viscosity of sputum due to changes in its rheological and physico-chemical properties), mucostasis (stagnation of thick viscous sputum in the bronchi). These disorders contribute to colonization of the bronchial mucosa by infectious agents and further damage to the bronchial wall.
The endoscopic picture of chronic bronchitis in the acute phase is characterized by hyperemia of the bronchial mucosa, the presence of mucopurulent or purulent secretions in the lumen of the bronchial tree, in the later stages – atrophy of the mucous membrane, sclerotic changes in the deep layers of the bronchial wall.
Against the background of inflammatory edema and infiltration, hypotonic dyskinesia of large and collapse of small bronchi, hyperplastic changes in the bronchial wall, bronchial obstruction easily joins, which supports respiratory hypoxia and contributes to the increase in respiratory failure in chronic bronchitis.
The clinical and functional classification of chronic bronchitis identifies the following forms of the disease:
- By the nature of the changes: catarrhal (simple), purulent, hemorrhagic, fibrinous, atrophic.
- According to the level of lesion: proximal (with predominant inflammation of large bronchi) and distal (with predominant inflammation of small bronchi).
- By the presence of a bronchospastic component: non-obstructive and obstructive bronchitis.
- According to the clinical course: chronic bronchitis of latent course; with frequent exacerbations; with rare exacerbations; continuously recurrent.
- According to the phase of the process: remission and exacerbation.
- By the presence of complications: chronic bronchitis complicated by pulmonary emphysema, hemoptysis, respiratory failure of varying degrees, chronic pulmonary heart (compensated or decompensated).
Symptoms of chronic bronchitis
Chronic non-obstructive bronchitis is characterized by a cough with mucopurulent sputum. The amount of bronchial secretions coughed up outside of exacerbation reaches 100-150 ml per day. In the phase of exacerbation of disease, cough increases, sputum becomes purulent, its amount increases; subfebrility, sweating, weakness are added.
With the development of bronchial obstruction, expiratory dyspnea, swelling of the neck veins on exhalation, wheezing, whooping cough-like unproductive cough are added to the main clinical manifestations. The long-term course of disease leads to thickening of the terminal phalanges and finger nails (“drumsticks” and “watch glasses”).
The severity of respiratory failure in chronic bronchitis can vary from slight shortness of breath to severe ventilation disorders requiring intensive therapy and ventilation. Against the background of exacerbation of this disease, decompensation of concomitant diseases may occur: coronary heart disease, diabetes mellitus, dyscirculatory encephalopathy, etc. Criteria for the severity of exacerbation of this disease are the severity of the obstructive component, respiratory failure, decompensation of concomitant pathology.
With catarrhal uncomplicated chronic bronchitis, exacerbations occur up to 4 times a year, bronchial obstruction is not pronounced (FEV1 > 50% of the norm). More frequent exacerbations occur with obstructive chronic bronchitis; they are manifested by an increase in the amount of sputum and a change in its nature, significant violations of bronchial patency (FEV1 < 50% of the norm), exacerbation of concomitant diseases. Chronic purulent bronchitis occurs with constant sputum secretion, a decrease in FEV1 < 50% of the normative indicators, decompensation of concomitant pathology and the development of respiratory failure.
In the diagnosis of chronic bronchitis, it is essential to clarify the anamnesis of the disease and life (complaints, smoking experience, occupational and household hazards). Auscultative signs of chronic bronchitis are hard breathing, elongated exhalation, dry wheezing (whistling, buzzing), wet multi-caliber wheezing. With the development of emphysema of the lungs, a box percussion sound is determined. Confirmatory methods:
- Radiological. Verification of the diagnosis is facilitated by lung x-ray. The X–ray picture in chronic bronchitis is characterized by a mesh deformation and an increase in the pulmonary pattern, in a third of patients – signs of emphysema of the lungs. Radiation diagnostics makes it possible to exclude pneumonia, tuberculosis and lung cancer. With the help of bronchography, the architectonics of the bronchial tree is evaluated, the presence of bronchiectasis is excluded.
- Laboratory. Microscopic examination of sputum reveals its increased viscosity, grayish or yellowish-green color, mucopurulent or purulent character, a large number of neutrophilic leukocytes. Bacteriological sputum culture makes it possible to identify microbial pathogens (Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae, Moraxella catarrhalis, Klebsiella pneumoniae, Pseudomonas spp., Enterobacteriaceae, etc.).
- Endoscopic. The degree of activity and the nature of inflammation in chronic bronchitis is clarified during diagnostic bronchoscopy. With difficulties in collecting sputum, bronchoalveolar lavage and bacteriological examination of bronchial flushing waters are indicated.
- Functional. The severity of violations of the function of external respiration is determined during spirometry. The spirogram in patients with chronic bronchitis demonstrates a decrease in VEL of varying degrees, an increase in MOD; with bronchial obstruction, a decrease in VF and MVL indicators. With pneumotachography, there is a decrease in the maximum volume exhalation rate.
From laboratory tests for chronic bronchitis, a general analysis of urine and blood is carried out; determination of total protein, protein fractions, fibrin, sialic acids, CRP, immunoglobulins, etc. indicators. With severe respiratory insufficiency, the CBS and the gas composition of the blood are examined.
Chronic bronchitis treatment
Exacerbation of chronic bronchitis is treated inpatient, under the supervision of a pulmonologist. At the same time, the basic principles of treatment of acute bronchitis are observed. It is important to exclude contact with toxic factors (tobacco smoke, harmful substances, etc.).
Pharmacotherapy of chronic bronchitis includes the appointment of antimicrobial, mucolytic, bronchodilating, immunomodulatory drugs. For antibacterial therapy, penicillins, macrolides, cephalosporins, fluoroquinolones, tetracyclines are used orally, parenterally or endobronchially. Mucolytic and expectorant agents are used in difficult-to-separate viscous sputum. In order to relieve bronchospasm in chronic bronchitis, bronchodilators are indicated. It is mandatory to take immunoregulatory agents.
In severe chronic bronchitis, therapeutic (sanitization) bronchoscopy, bronchoalveolar lavage can be performed. To restore the drainage function of the bronchi, auxiliary therapy methods are used: alkaline and medicinal inhalations, postural drainage, chest massage (vibration, percussion), respiratory gymnastics, physiotherapy (UHF and electrophoresis on the chest, diathermy), speleotherapy. Out of exacerbation, it is recommended to stay in sanatoriums of the Southern coast of Crimea.
In chronic bronchitis complicated by pulmonary heart failure, oxygen therapy, cardiac glycosides, diuretics, anticoagulants are indicated.
Prognosis and prevention
Timely comprehensive treatment of chronic bronchitis allows you to increase the duration of the remission period, reduce the frequency and severity of exacerbations, but does not provide a lasting cure. The prognosis is aggravated by the addition of bronchial obstruction, respiratory failure and pulmonary hypertension. Preventive work to prevent disease consists in promoting smoking cessation, eliminating adverse chemical and physical factors, treating concomitant pathology, improving immunity, timely and complete treatment of acute bronchitis.