Enfizema of the lungs

Lung anemia - characterized by a pathological expansion of air spaces distal to the terminal bronchioles, which is accompanied by destructive changes in the alveolar walls; One of the frequent forms of chronic nonspecific lung diseases. Distinguish primary (idiopathic) emphysema of the lungs, which develops without previous bronchopulmonary disease, and secondary (obstructive) emphysema-most often complication of chronic obstructive bronchitis. Depending on the prevalence, emphysema may be diffuse or focal.

Etiology, pathogenesis. There are two groups of causes leading to the development of emphysema. The first group consists of factors that violate the elasticity and strength of pulmonary structural elements: pathological microcirculation, changes in the properties of the surfactant, congenital deficiency of α-antitrypsin, gaseous substances (cadmium compounds, nitrogen oxides, etc.), as well as tobacco smoke, dust particles in the inspired air . These causes can lead to the development of a primary, always diffuse emphysema. At the heart of its pathogenesis is the pathological restructuring of the entire respiratory part of the lung; Weakening the elastic properties of the lung leads to the fact that during exhalation and, consequently, an increase in intrathoracic pressure, small bronchi that do not have their cartilaginous framework and are devoid of elastic traction of the lung passively fall, increasing this bronchial resistance on exhalation and increasing pressure in the alveoli. Bronchial permeability on inspiration with primary emphysema is not impaired.

Factors of the second group contribute to increasing pressure in the respiratory part of the lungs and increase the tension of the alveoli, alveolar courses and respiratory bronchioles. The most important among them is airway obstruction, which occurs with chronic obstructive bronchitis. This disease becomes the main cause of the development of secondary or obstructive pulmonary emphysema, since it is under it that conditions are created for the formation of a valvular alveolar mechanism. Thus, lowering the intrathoracic pressure during inspiration, causing a passive stretching of the bronchial lumen, reduces the degree of bronchial obstruction available; The positive intrathoracic pressure during the exhalation causes additional compression of the bronchial branches and, exacerbating the already existing bronchial obstruction, promotes the retention of the inspired air in the alveoli and their hyperextension. Important is the spread of the inflammatory process from the bronchioles to the adjacent alveoli with the development of the alveolitis and the destruction of interalveolar septa. The causes of focal (localized, irregular) pulmonary emphysema may be incomplete valvular obturation of the bronchus of inflammatory or tumorigenesis; Atelectasis or cirrhosis of the lung; Congenital pathology (congenital fractional emphysema, congenital unilateral emphysema).

Secondary emphysema is characterized by swelling of respiratory bronchioles and a change in the shape of predominantly those alveoli that lie close to them (centroacinar emphysema). With progression to the pathological process, the entire acinus (lobule) can be included. The alveoli are flattened, the mouths are enlarged, smooth muscle bundles are hypertrophied, then dystrophic. Elastic fibers are straightened. The walls of respiratory bronchioles are thinned, the number of capillaries and cellular elements in them is reduced. In the late stages of emphysema, there is a disturbance and complete disappearance of the structural elements of the respiratory part of the lungs. With primary emphysema, there is uniform damage to all alveoli that form part of the lung acinus (panacinar emphysema), atrophy of interalveolar septa; Reduction of capillary bed. Inflammatory changes in the bronchi, bronchioles are not expressed, and their obstruction associated with inflammatory edema does not occur.

Symptoms, course. Dyspnoea, barrel chest, reduction of her respiratory excursions, widening of the intercostal spaces, swelling of the supraclavicular areas, box percussion sound, weakened breathing, a decrease in the region of relative dullness of the heart, a low diaphragm standing and a decrease in its mobility, an increase in the transparency of the pulmonary fields on the roentgenogram. Primary emphysema is much more severe than secondary, with severe dyspnea, with which (without a preceding cough) the disease begins; In patients already at rest, the volume of ventilation is extremely large, so their tolerance to exercise is very low. Known for patients with primary emphysema, the symptom of "puffing" (covering the exhalation of the oral cavity with swelling of the cheeks) is caused by the need to increase intrabronchial pressure during exhalation and thereby reduce the expiratory collapse of small bronchi, which hinders the increase in the volume of ventilation. With primary emphysema less than the secondary, the gas composition of the blood is disturbed, cyanosis ("pink" type of emphysema) is poorly expressed, increased ventilation up to the terminal stage maintains satisfactory oxygenation of the blood, therefore, there is no compensatory polyglobule characteristic of secondary emphysema. In primary emphysema, unlike the secondary one, the chronic pulmonary heart usually does not develop.

X-ray for primary emphysema is characterized by a uniform increase in the transparency of pulmonary fields and impoverishment of the pulmonary pattern, especially in the lower parts of the lungs, a low diaphragm position. With secondary emphysema, the transparency of the lower parts of the lungs is reduced due to peribronchial changes, the diaphragm can not move, since the total volume of the lungs varies insignificantly. When differentiating these two forms of diffuse emphysema, methods of functional investigation of external respiration are used.

Treatment of primary emphysema is symptomatic: respiratory gymnastics aimed at maximum inclusion of the diaphragm in the act of breathing; Courses of oxygen therapy, the exclusion of smoking and other harmful effects, including professional; Restriction of physical activity. The therapy of inhibitors with (one) -antitrypsin is being developed. Accession of bronchopulmonary infection requires the appointment of antibiotics. With secondary emphysema, treatment of the underlying disease and therapy aimed at arresting respiratory and heart failure are performed. There are attempts to surgically treat focal emphysema - resection of the affected areas of the lung. Prevention of secondary emphysema is reduced to the prevention of chronic obstructive bronchitis.