Definition
Always unpredictable, the spontaneous variant of pneumothorax is probably the most common form, affecting especially young males with a slender and slender build.
Responsible for respiratory difficulties, even important, spontaneous pneumothorax defines a complex clinical picture, consisting of the accumulation of air or gas in the pleural cavity and the consequent collapse of the lung.
Pleural cable: connecting element between the lung and the chest wall.
Classification
Spontaneous pneumothorax is divided into several sub-categories:
- NEONATAL SPONTANEOUS PNEUMOTORACE: newborns suffering from severe lung diseases such as SAM (meconium aspiration syndrome) and RDS (respiratory distress syndrome) may develop complications such as spontaneous pneumothorax. Most newborns suffering from spontaneous pneumothorax do not complain of symptoms: this constitutes a serious limit for an early diagnosis. In other infants, on the other hand, the pathology begins with obvious prodromes, such as cyanosis, hypoxia, hypercapnia and bradycardia.
- PRIMARY OR PRIMITIVE SPONTANEOUS PNEUMOTORACE: occurs in the absence of an apparent cause or pulmonary disease. Most affected patients recover spontaneously in 7-10 days from onset, without suffering long-term damage. The pathogenesis is generally linked to the rupture of so-called blebs, accumulations of air undermined between the lung and visceral pleura. It is estimated that the spontaneous primitive variant constitutes 50-80% of the spontaneous forms.
- SECONDARY SPONTANEOUS PNEUMOTORACE: the collapse of the lung is always a consequence of an underlying lung disease. The symptoms are generally more marked than the primitive form and the severity of the clinical condition can put the patient's life at risk (in particular if the secondary spontaneous pneumothorax is not adequately treated). In most cases, secondary spontaneous pneumothorax affects subjects over the age of 40.
From a physiopathological point of view, a further classification of spontaneous pneumothorax can be performed:
- Spontaneous open pneumothorax: air enters and exits continuously from the pleural cavity, so the lung collapses completely, as it is subjected to the action of atmospheric pressure.
- Spontaneous pneumothorax closed: the lung is not completely collapsed, since the communication with the pleural cavity is closed, so there is no air leakage.
- Spontaneous pneumothorax with valve (or hypertensive pneumothorax): this is the most dangerous variant of pneumothorax. The air penetrates into the pleural cavity during the inspiratory act, without exiting during expiration: consequently, the intrapleural pressure increases excessively, until it literally crushes the lung. This clinical condition can jeopardize the survival of the patient: the hypertensive pneumothorax can progress to induce restrictive ventilatory deficit and cardiovascular collapse.
Causes and risk factors
Spontaneous pneumothorax can result in a rupture of the pulmonary structures and the visceral pleura: a similar condition favors the communication of the airways with the thoracic cord, creating damage.
We have seen that only the secondary variant of spontaneous pneumothorax is related to pulmonary diseases. The following are the morbid conditions most often observed in affected patients:
- AIDS
- pulmonary abscess
- asthma
- COPD
- Cancer: primary pulmonary carcinoma, carcinoid, mesothelioma, metastatic sarcoma
- Chronic bronchitis associated with pulmonary fibro-emphysema
- thoracic endometriosis
- bullous emphysema (most cases)
- cystic fibrosis
- vascular infarction
- lung infections
- metastasis
- sarcoidosis
- Marfan syndrome (disease affecting connective tissue)
- ankylosing spondylitis
Although an apparently observable cause is not found in patients with primary spontaneous pneumothorax, it is assumed that the blisters (accumulations of air developed inside the lung) and blebs (accumulations of air between the lung and visceral pleura) can heavily affect the genesis of disorder. It is estimated that in almost all spontaneous pneumothorax patients the videotoracicoscopy verifies the presence of these bullous lesions.
Remarks:
The close correlation between the sudden manifestation of the symptoms of spontaneous pneumothorax and the performance of an intense sport practice is important. Indeed, it seems that pulmonary hyperventilation and muscular hyperactivity can be considered possible triggers. In this sense, the most risky sports are weight lifting and diving. However, it is conceivable that even the appearance or persistence of a particularly irritating cough may cause the pneumothorax to burst.
Despite the above, spontaneous pneumothorax appears suddenly in most patients, even at rest.
Deepening: how can scuba diving affect the onset of pneumothorax?
During scuba diving, the air breathed through the breathing apparatus must have a pressure equal to that of the environment; the same air, however, increases in volume as the environmental pressure decreases, thus expanding in the ascent section. If the increase in volume is excessive, it is possible to hypothesize the rupture of the pulmonary alveoli: in similar situations, the passage of air inside the pleural cavity is favored, therefore the collapse of the lung (which results in the pneumothorax).
Symptoms
Except for asymptomatic cases, the majority of patients with spontaneous pneumothorax suffer from a peculiar "pleural" pain, limited at the level of the hemithorax affected by the condition.
The clinical onset of symptoms depends on both the age of the patient and the extension of the pneumothorax. In affected children (spontaneous neonatal pneumothorax), for example, a flutter, a mediastinal vibration is observed more often.
Many hospitalized patients report symptoms with expressions such as "violent thoracic dagger pain ", often associated with more or less severe breathing difficulties. Dyspnea is clearly due to lung collapse; young people seem to experience this disorder much more lightly than in the elderly.
Again, among the symptoms associated with spontaneous pneumothorax, agitation and the feeling of suffocation cannot be lacking, reported by a good part of the patients.
The patient suffering from spontaneous pneumothorax appears to be in difficulty, often in a clear state of cyanosis. It is possible, at times, to detect tachycardia (> 135 bpm), jugular turgidity due to the involvement of the hollow veins and increase in the size of the pathology affected by the disease.
Diagnosis
The chest X-ray detects the air accumulated inside the pleural cavity, the lowering of the diaphragm, the subcutaneous emphysema and the collapse of the lung towards the hilum.
The differential diagnosis must be set with:
- pleural effusion → the manifestation of symptoms generally occurs less abruptly than spontaneous pneumothorax
- chest pain, pleurodynia (severe pain of the pleural nerves and intercostal muscles) and Bornholm disease (infection of the intercostal muscles, with possible involvement of the pleura) → characterized by an unpleasant and constant perception of breathlessness
- pulmonary embolism → symptoms include hemoptysis and rales at the affected area
Therapy
In general, we speak of eclectic therapeutic behavior, in the sense that the therapy is heterogeneous and varied, because it is subordinate both to the triggering cause (when identifiable), and to the prediction of spontaneous reabsorption of the lesion. When the damage is slight and affects a small portion of the lung, spontaneous healing is expected: in such circumstances, absolute rest is recommended.
More factors intervene in the choice of a therapy rather than another. Consideration should be given to the severity of symptoms, the patient's age, the degree of respiratory distress and the underlying pathology (when detectable).
Even in the absence of symptoms (or in the case of mild respiratory distress ) the newborn affected by spontaneous pneumothorax should be carefully monitored. Particular attention must be paid to monitoring heart and respiratory rates, arterial pressure and arterial oxygen saturation.
In case of need, it is possible to administer oxygen for a few hours, in order to reduce pneumothorax and speed healing.
For the adult man and for the young man suffering from spontaneous pneumothorax, the preferred therapy is pleural drainage with fall or suction, very useful both for the removal of intrapleural air and to prevent any further accumulation.
Medical statistics show that chest drainage to treat the first episode of spontaneous pneumothorax has a very high success rate, estimated at around 90%. However, in case of relapses, this value drops to 52% (for the first repeat offender) and to 15% for the second one.
In case of recurrent recurrences or lack of response to pleural drainage, it is conceivable to resort to a surgical treatment. Pelurodesis (promotes adhesion of the lung to the thoracic wall) or pleurectomy (partial surgical excision of the parietal pleura) constitute the preferred surgical treatments for the treatment of pneumothorax.
Under certain special conditions, surgery is recommended as early as the first episode of spontaneous pneumothorax. In similar situations, surgery is the preferred therapy in case of:
- hemopneumothorax (accumulation of air and blood in the pleural cavity)
- bilateral pneumothorax
- regressive history of contralateral pneumothorax
- hypertensive pneumothorax
In conclusion, it is necessary to request medical assistance even in the case of suspected onset of pulmonary collapse: in cases of extreme severity, in fact, an inadequately treated pneumothorax can degenerate up to the induction of cardiac arrest, shock, hypoxemia, respiratory failure and death.
