Spontaneous pneumothorax is a pathological condition characterized by a sudden violation of the integrity of the visceral pleura and the flow of air from the lung tissue into the pleural cavity. The development of this pathology is accompanied by acute chest pain, shortness of breath, tachycardia, pallor of the skin, acrocyanosis, subcutaneous emphysema, the patient’s desire to take a forced position. For the purpose of primary diagnosis, lung x-ray and diagnostic pleural puncture are performed; to determine the causes of the disease, an in-depth examination (CT, MRI, thoracoscopy) is required. Treatment includes drainage of the pleural cavity with active or passive evacuation of air, videothoracoscopic or open interventions (pleurodesis, bull removal, lung resection, pulmonectomy, etc.)
Spontaneous pneumothorax in clinical pulmonology is understood as idiopathic, spontaneous pneumothorax, not associated with trauma or iatrogenic therapeutic and diagnostic interventions. Disease develops statistically more often in men and prevails among people of working age (20-40 years), which determines not only the medical, but also the social significance of the problem.
If in traumatic and iatrogenic pneumothorax, a causal relationship between the disease and external influences is clearly traced (chest injury, puncture of the pleural cavity, catheterization of central veins, thoracocentesis, pleural biopsy, barotrauma, etc.), then in the case of spontaneous pneumothorax, such conditionality is absent. Therefore, the choice of adequate diagnostic and therapeutic tactics is the subject of increased attention of pulmonologists, thoracic surgeons, phthisiologists.
Spontaneous pneumothorax causes
Primary spontaneous pneumothorax develops in people who do not have clinically diagnosed lung pathology. However, during diagnostic videothoracoscopy or thoracotomy, subpleural emphysematous bulls are detected in 75-100% of cases in this contingent of patients. The relationship between the frequency of spontaneous pneumothorax and the constitutional type of patients was noted: the disease occurs more often in thin, tall young people. Smoking increases the risk of spontaneous pneumothorax up to 20 times.
Secondary spontaneous pneumothorax can develop against the background of a wide range of pathologies:
- lung diseases (COPD, cystic fibrosis, bronchial asthma)
- respiratory tract infections (pneumocystis pneumonia, abscessed pneumonia, tuberculosis). In the case of a breakthrough into the pleural cavity of a lung abscess, a pyopneumothorax develops.
- interstitial lung diseases (Beck’s sarcoidosis, pneumosclerosis, lymphangioleiomyomatosis, Wegener’s granulomatosis), systemic diseases (rheumatoid arthritis, scleroderma, Marfan syndrome, Bekhterev’s disease, dermatomyositis and polymyositis)
- malignant neoplasms (sarcomas, lung cancer).
Relatively rare forms of disease include menstrual and neonatal pneumothorax. Menstrual pneumothorax is etiologically associated with thoracic endometriosis and develops in young women in the first two days from the beginning of menstruation. The probability of recurrence of menstrual pneumothorax, even against the background of conservative therapy of endometriosis, is about 50%, therefore, pleurodesis can be performed immediately after diagnosis in order to prevent repeated episodes of spontaneous pneumothorax.
Neonatal pneumothorax – spontaneous pneumothorax of newborns occurs in 1-2% of children, 2 times more often in boys. Pathology may be associated with problems of lung expansion, respiratory distress syndrome, rupture of lung tissue during ventilation, lung malformations (cysts, bullae).
The degree of severity of structural changes depends on the time that has elapsed since the onset of spontaneous pneumothorax, the presence of initial pathological disorders in the lung and visceral pleura, the dynamics of the inflammatory process in the pleural cavity.
With spontaneous pneumothorax, there is a pathological pulmonary-pleural communication that causes the ingress and accumulation of air in the pleural cavity; partial or complete collapse of the lung; displacement and flotation of the mediastinum.
An inflammatory reaction develops in the pleural cavity 4-6 hours after an episode of spontaneous pneumothorax. It is characterized by hyperemia, injection of pleural vessels, the formation of a small amount of serous exudate. Within 2-5 days, the swelling of the pleura increases, especially in the areas of its contact with the penetrated air, the amount of effusion increases, fibrin falls out on the surface of the pleura.
The progression of the inflammatory process is accompanied by the proliferation of granulations, fibrous transformation of the fallen fibrin. The collapsed lung is fixed in a compressed state and becomes incapable of straightening. In the case of hemothorax or infection, pleural empyema develops over time; bronchopleural fistula may form, supporting the course of chronic pleural empyema.
According to the etiological principle, primary and secondary form are distinguished. Primary form is spoken of in the absence of data for clinically significant pulmonary pathology. The occurrence of secondary form occurs against the background of concomitant pulmonary diseases.
Depending on the degree of lung collapse, there are:
- Partial (small, medium). With a small spontaneous pneumothorax, the lung decreases by 1/3 of the initial volume, with an average – by 1/2.
- Total. With a total pneumothorax, the lung subsides by more than half.
According to the degree of compensation of respiratory and hemodynamic disorders accompanying spontaneous pneumothorax, three phases of pathological changes were determined: the phase of persistent compensation, the phase of unstable compensation and the phase of decompensation (insufficient compensation).
- The phase of persistent compensation is observed in spontaneous pneumothorax of small and medium volume; it is characterized by the absence of signs of respiratory and cardiovascular insufficiency, VEL and MVL are reduced to 75% of the norm.
- The phase of unstable compensation corresponds to the collapse of the lung by more than 1/2 volume, the development of tachycardia and shortness of breath during exercise, a significant decrease in external respiration.
- The decompensation phase is manifested by shortness of breath at rest, pronounced tachycardia, microcirculatory disorders, hypoxemia, and a decrease in FVD values by 2/3 or more from normal values.
Spontaneous pneumothorax symptoms
According to the nature of clinical symptoms, there is a typical variant of spontaneous pneumothorax and a latent (erased) variant. A typical clinic of spontaneous pneumothorax may be accompanied by moderate or violent manifestations.
In most cases, the primary spontaneous pneumothorax develops suddenly, in the midst of complete health. Already in the first minutes of the disease, acute stabbing or squeezing pains are noted in the corresponding half of the chest, acute shortness of breath. The severity of the pain varies from slightly intense to very severe. Increased pain occurs when trying to take a deep breath, cough. Pain sensations spread to the neck, shoulder, arm, abdomen or lower back.
Within 24 hours, the pain syndrome decreases or disappears completely, even if spontaneous pneumothorax is not resolved. Sensations of respiratory discomfort and lack of air occur only during physical exertion.
With violent clinical manifestations of this disease, a painful attack and shortness of breath are extremely pronounced. Short-term fainting, pallor of the skin, acrocyanosis, tachycardia, a feeling of fear and anxiety may occur. Patients spare themselves: restrict movement, take a half-sitting or lying position on the sick side. Subcutaneous emphysema, crepitation in the neck, upper extremities, and trunk often develops and progressively increases. In patients with secondary spontaneous pneumothorax, due to the limited reserves of the cardiovascular system, the disease is more severe.
Complicated variants of the course of spontaneous pneumothorax include the development of tense pneumothorax, hemothorax, reactive pleurisy, simultaneous bilateral collapse of the lungs. Accumulation and prolonged presence of infected sputum in the collapsed lung leads to the development of secondary bronchiectasis, repeated episodes of aspiration pneumonia in a healthy lung, abscesses. Complications of spontaneous pneumothorax develop in 4-5% of cases, but they can pose a threat to the life of patients.
Examination of the chest reveals smoothness of the intercostal relief, restriction of respiratory excursion on the side of spontaneous pneumothorax, subcutaneous emphysema, swelling and dilation of the neck veins. On the side of the collapsed lung, there is a weakening of vocal tremor, tympanitis with percussion, with auscultation – the absence or sharp weakening of respiratory noises. The primary importance in the diagnosis is given to:
- Radiation methods. Chest X-ray and chest X-ray make it possible to estimate the amount of air in the pleural cavity and the degree of lung collapse, depending on the prevalence of spontaneous pneumothorax. Control X-ray examinations are carried out after any therapeutic manipulations (puncture or drainage of the pleural cavity) and allow you to evaluate their effectiveness. In the future, with the help of high-resolution CT or MRI of the lungs, the cause of spontaneous pneumothorax is determined.
- Therapeutic and diagnostic thoracoscopy. A highly informative method used in the diagnosis of spontaneous pneumothorax is thoracoscopy. During the study, it is possible to identify subpleural bulls, tumor or tuberculous changes in the pleura, and to perform a biopsy of the material for morphological examination.
Spontaneous pneumothorax of latent or erased course must be differentiated from giant bronchopulmonary cyst and diaphragmatic hernia. In the latter case, the radiography of the esophagus helps the differential diagnosis.
Spontaneous pneumothorax treatment
Medical standards require the earliest possible evacuation of air accumulated in the pleural cavity and the achievement of lung expansion. The generally accepted standard is the transition from diagnostic tactics to therapeutic. Thus, obtaining air during thoracocentesis is an indication for drainage of the pleural cavity. Pleural drainage is installed in the II intercostal space along the midclavicular line, after which it joins the active aspiration.
Improvement of bronchial patency and evacuation of viscous sputum facilitate the task of straightening the lung. For this purpose, therapeutic bronchoscopy (bronchoalveolar lavage, tracheal aspiration), inhalation with mucolytics and bronchodilators, respiratory gymnastics, oxygen therapy are carried out.
If no lung expansion occurs within 4-5 days, they switch to surgical tactics. It may consist in thoracoscopic diathermocoagulation of bullae and adhesions, elimination of bronchopleural fistulas, implementation of chemical pleurodesis. With recurrent spontaneous pneumothorax, depending on its causes and also the condition of the lung tissue, atypical marginal lung resection, lobectomy or even pneumonectomy may be indicated.
With primary spontaneous pneumothorax, the prognosis is favorable. It is usually possible to achieve lung expansion by minimally invasive methods. With secondary spontaneous pneumothorax, relapses of the disease develop in 20-50% of patients, which dictates the need to eliminate the root cause and choose more active therapeutic tactics. Patients who have undergone spontaneous pneumothorax should be under the supervision of a thoracic surgeon or pulmonologist.
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