Pneumothorax is the term used to describe the entry of air into the pleural cavity. There are many different causes. Tension pneumothorax is a life-threatening complication. X-rays and computer tomography play an important role in the diagnosis. As far as treatment options are concerned, there is the possibility of chest drainage in addition to conservative therapy.
The entry of air between the parietal and visceral leaflets of the pleura causes the capillary forces in the pleural cavity to be suspended. The adhesion between the pleural sheets is lost and the lung no longer follows the thoracic movements. The result is a partial or complete collapse of the affected lung. Air can enter from the outside (through an injury) or from the inside (through a tear in the lung tissue or a bronchopleural fistula). Upper lobe segments 1, 2 and 3 are particularly predisposed to pneumothorax, as these are relatively more stretched during deep inspiration [1].
The causes of pneumothorax are listed in Table 1.
A rupture of the visceral pleura with a connection between the pleural cavity and the lung in a transthoracic or transdiaphragmatic fistula with pre-existing pneumoperitoneum leads to pneumothorax. Spontaneous pneumothorax can also be caused by subpleural emphysema blisters and esophageal rupture [6]. Smoking is also a risk factor for spontaneous pneumothorax [5].
The symptoms manifest themselves with sudden, stabbing, possibly breathing-dependent pain in the affected half of the thorax, dyspnoea and shortness of breath. Coughing and a dry cough may also occur, as well as the affected half of the thorax “lagging behind” when breathing.
Various classifications help to better categorize the clinical picture of pneumothorax (Table 2).
The therapeutic aim is to remove the air from the pleural cavity with complete expansion of the lung and to prevent recurrence [2,3]. If it is an idiopathic spontaneous pneumothorax and occurs for the first time, it can usually be treated conservatively. If the spontaneous pneumothorax is less severe, treatment consists of close monitoring of the X-ray findings, albeit in close conjunction with the clinical symptoms. In all other cases, a so-called thoracic drainage is inserted so that the negative pressure within the thorax is restored and the lung expands.
If the pneumothorax is caused by other traumatic injuries such as rib fractures or a hemothorax (blood in the pleural cavity), a chest drain must always be inserted to drain the pneumothorax and any abnormal fluids such as blood or other effusion. In the case of a tension pneumothorax, there is a maximum emergency indication and the drain must be inserted immediately.
Surgical correction is often recommended in the event of a recurrence of a pneumothorax, persistent air loss over 3-4 days or in the presence of a secondary pneumothorax (i.e. a lung disease). This involves endoscopy (thoracoscopy) of the affected chest cavity under general anesthesia. In order to close the leak in the pleura, a sparing wedge resection is performed in the affected section of the lung. In addition, a so-called abrasion of the pleura is performed. In certain cases of recurrence of pneumothorax, a talc pleurodesis, an adhesion of the visceral and parietal pleura using talcum powder, is performed [4].
X-rays of the lungs should be taken in a standing position and – if not possible – in a lateral position. The image in expiration enlarges the intrapleural air relative to the lung air, the pneumothorax becomes more clearly recognizable, and in a tension pneumothorax the lung is collapsed and almost homogeneously compressed. The diaphragm is low, the intercostal spaces are dilated and the mediastinum is displaced contralaterally [6].
Computed tomography scans are also very good at detecting pneumothorax. In traumatized patients, a reliable distinction can be made between an accompanying serothorax or haemothorax.
Magnetic resonance imaging does not play a role in the diagnosis of pneumothorax.
Case study
Case report 1 shows a complete left-sided pneumonia (Fig. 1A and B) in a 32-year-old patient on chest X-ray. The patient complained of spontaneous dyspnea and clinically presented with tracheobronchitis. On auscultation, a reduced ventilation on the left was conspicuous. There was no evidence of trauma in the medical history.
X-ray control showed a restitutio ad integrum (Fig. 1C).
Case 2 demonstrates the course after initial diagnosis of a right mantle pneumothorax following blunt chest trauma with subsequent dyspnea (Fig. 2A). A small pleural effusion was present on the right basolateral side. A CT scan more than a year later showed a small residual basal pleural effusion with a scar at the edge (Fig. 2B).
Take-Home-Messages
- In pneumothorax, air enters between the parietal and visceral leaflets of the pleura.
- The loss of adhesion of the pleural sheets can result in a partial or complete pneumothorax.
- There are various causes of pneumothorax.
- Spontaneous pneumothorax can be treated conservatively, depending on the symptoms.
- Suction drainage or pleurodesis are recommended for recurrence or secondary pneumothorax.
Literature:
- Hircin E, Antwerpes F: Pneumothorax, https://flexikon.doccheck.com/de,(last accessed 02.04.2024)
- Arshad H, et al: Acute pneumothorax. Crit Care Nurs Q 2016; 39(2).
- DeMaio A, Semaan R: Management of Pneumothorax. Clin Chest Med 2021; 42(4): 729–738.
- Pneumothorax Therapie, www.usz.ch/fachbereich/thoraxchirurgie/angebot/pneumothorax, (last accessed 02.04.2024)
- Huan NC, Sidhu C, Thomas R: Pneumothorax: Classification and Etiology. Clin Chest Med 2021; 42(4): 711–727.
- Lange S: Radiologische Diagnostik der Thoraxerkrankungen. 2., völlig neu bearbeitete und erweiterte Auflage. Georg Thieme Verlag Stuttgart, New York: 1996; pp. 179–180.
InFo PNEUMOLOGIE & ALLERGOLOGIE 2024; 6(3): 37–39
