Atelectasis - what is it? The answer to this medical question is known only to experienced professionals. But you don’t need a doctor to find out. You can learn more about atelectasis from the materials in this article.
Definition of the term
Atelectasis is a pathological condition characterized by a loss of airiness in the entire lung or its specific area. The term in question is of Greek origin. Translated into Russian, it means "failed" or "incomplete stretching of the tissue."
Development reasons
Atelectasis is a subsidence of a segment of the lung. Several factors can lead to the development of such a pathological condition. We list the main ones right now:
- The increase in surface tension observed on the walls of the alveoli. As a rule, such a pathology is caused by pulmonary edema of non-cardiogenic or cardiogenic origin, as well as a lack of surfactant or infectious processes.
- Compression of the airways or lung, which is caused by various external factors (for example, a mediastinal tumor, an abnormality in the development of large blood vessels, lymphadenopathy, myocardial hypertrophy , etc.).
- Pathology of the mucous membrane (inner) of the walls of the bronchus (for example, bronchomalacia, deformation, swelling or edema).
- Obstruction or so-called obstruction of the lumen of the bronchi with foreign bodies, mucus, caseous masses (for example, with tuberculosis), as well as swelling of the mucous membrane.
- Violations of the natural excursion of the chest, which arise due to paralysis of the phrenic nerve, general anesthesia, scoliosis or neuromuscular diseases.
- Increased internal pressure in the pleural cavity (including hemothorax, hydrothorax, empyema, pneumothorax).
Why else can atelectasis occur? The causes of this condition are often hidden in acute massive lung collapse, which occurs as a postoperative complication due to prolonged immobility of the patient, oxygen overdose, hypothermia, the use of large doses of sedatives and opiates, as well as vasodilator drugs.
Risk factors
Who has atelectasis the most? This disease is inherent in people with obesity, cystic fibrosis and bronchial asthma. Also, heavy smokers are exposed to it.
Classification
By origin, atelectasis of the lobe of the lung can be congenital (i.e. primary) or acquired (i.e. secondary).
By primary disease is meant a condition when a newborn baby does not have lung expansion. As for the acquired atelectasis, in this case there is a decline in the lung tissue that previously participated in the breathing process.
It cannot be said that such phenomena should be distinguished from intrauterine atelectasis, that is, the airless state of the lungs that is observed in the fetus, and physiological (that is, hypoventilation that occurs in completely healthy people and represents a certain functional reserve of lung tissue).
Types of disease
Depending on the volume of lung tissue that leaves the breathing process, the disease in question is divided into:
- acinous;
- segmental;
- lobular;
- total;
- shared.
It can also be two- or one-sided. By the way, the first variety is extremely dangerous and can quite easily lead to the death of the patient.
Types of disease
Depending on the etiopathogenetic factors, the considered pathology of the pulmonary system is divided into the following types:
- Compression atelectasis, or collapse, of the lung. This condition is caused by compression of the lung tissue from the outside, as well as the accumulation of exudate, air, blood or pus in the pleural cavity.
- Obstructive atelectasis. This phenomenon is associated with a mechanical violation of the patency of the trachea and bronchi.
- Disk-shaped atelectasis of the lung. Such a pathology usually develops after chest contusion or rib fracture.
- Contractional - caused by compression of the alveoli with fibrous tissue (in the subpleural parts of the lungs).
- Acinar - associated with a lack of surfactant (most often occurs in adults and newborns with respiratory distress syndrome).
It should also be noted that the disease in question can be reflex and postoperative, developing gradually and acutely, uncomplicated and complicated, transient and persistent.
Symptoms
The severity of the clinic of atelectasis of the lung depends on the volume of non-functioning and the rate of decline of the lung tissue. Microatelectases, single segmental atelectasis, and median lobe syndrome are very often asymptomatic.
As for the acute disease, it has a pronounced symptomatology. In this case, the patient feels sudden pain, paroxysmal shortness of breath, cyanosis, dry cough, tachycardia and arterial hypotension. With a sharp increase in respiratory failure, even death can occur.
Upon examination of the patient, lagging of the affected lobe of the lung during breathing, as well as a decrease in the respiratory excursion of the chest, are revealed. In addition, a dull percussion or shortened sound is determined above the focus of atelectasis. At the same time, breathing is sharply weakened (may not be audible).
Complications of atelectasis
With the gradual shutdown of lung segments from ventilation, the signs of the disease are less pronounced. But subsequently in the field of hypopneumatosis, atelectatic pneumonia develops.
The appearance of a cough with sputum, an increase in body temperature, as well as an increase in symptoms of intoxication indicate the onset of inflammation. In this case, the disease in question is complicated by the development of a lung abscess or abscessed pneumonia.
Diagnostics
Diagnosis of lung atelectasis is carried out by means of an X-ray examination of the respiratory organ in lateral and direct projections. In this case, a homogeneous darkening of the pulmonary field, as well as a displacement of the mediastinum towards the lobe that has fallen out of the breathing process, is revealed. In addition, X-rays show a high position of the dome of the diaphragm and increased airiness of the lung.
In doubtful cases, this research method is specified by CT. Also, to clarify the causes of obstructive atelectasis, bronchoscopy is used, and with prolonged atelectasis, angiopulmonography and bronchography are performed.
Treatment
Detection of lung atelectasis requires an active tactic from the doctor (pulmonologist, neonatologist, traumatologist or thoracic surgeon). Just born babies with primary lung atelectasis are sucked out of the respiratory organs with a rubber catheter. If required, tracheal intubation and lung expansion are performed.
With this type of disease, such as obstructive atelectasis, which was caused by a foreign body, it is extracted through therapeutic and diagnostic bronchoscopy.
If the collapse of the lung was caused by the accumulation of difficult secretions, then endoscopic sanitation of the bronchial tree is performed.
In order to eliminate postoperative atelectasis, tracheal aspiration, respiratory gymnastics, chest percussion massage, postural drainage, as well as inhalation with enzyme and bronchodilator drugs are performed.
It cannot be said that with lung atelectasis of any origin, the mandatory implementation of preventive anti-inflammatory therapy is required.
Forecast
Success in lung expansion depends on the timing of treatment initiation and the cause of atelectasis. With the complete elimination of the latter in the first three days, the prognosis for the restoration of the respiratory organ is favorable.
In advanced cases, the development of secondary changes in the declining share cannot be ruled out. Rapidly developed and massive atelectasis can lead to death.