The etiology and therapy of primary spontaneous pneumothoraces

Abstract

Primary spontaneous pneumothorax (PSP) remains a significant health problem in young adults. Subpleural blebs and bullae in the lung apices are likely to play important roles in pathogenesis. The optimal management of PSP has been a matter of debate and depends on the size of the pneumothorax, the symptoms and the time of occurrence. Observation or simple aspiration is used in the first episode, while surgery is recommended for recurrent or complicated pneumothorax. Recent advances in thoracoscopic surgery have provided a less invasive alternative in the surgical treatment of PSP, but there are concerns about higher recurrence rates than that following open thoracotomy. Studies have shown that the judicious use of chemical pleurodesis may decrease the rate of recurrence in surgical and nonsurgical patients. In this article, the etiology and pathophysiology of PSP are reviewed. The indications, safety and effects of currently available treatment modalities are also summarized.

Keywords:

• aspiration
• etiology
• pleurodesis
• pneumothorax
• thoracoscopy
• treatment

Financial & competing interests disclosure

The authors were supported by the Taiwan Ministry of Science and Technology (103-2325-B-002-014) and the Taiwan Lung Foundation. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Key issues

• Spontaneous pneumothorax is classified as primary or secondary according to whether there is a pre-existing respiratory disease. Generally, the primary form is found in patients younger than 50 years old without a pre-existing respiratory disease.

• Primary spontaneous pneumothorax (PSP) usually develops in young, tall, lean male patients. Subpleural blebs and bullae are likely to play major roles in the pathogenesis of PSP. The etiology of the blebs and bullae, however, remains unclear.

• Smoking is the most important risk factor contributing to the first onset or recurrence of PSP.

• A pneumothorax is classified as ‘small’ or ‘large’ based on the distance from the lung margin to the chest wall on a posteroanterior chest radiograph. A large or symptomatic pneumothorax requires intervention.

• The management of PSP depends on the size of the pneumothorax and the time of occurrence. In addition to evacuating air from the pleural space by simple aspiration or chest tube drainage, the management also focuses on stopping air leakage and preventing recurrence by surgical intervention or chemical pleurodesis.

• Simple aspiration is preferred over chest tube insertion in an uncomplicated first episode of PSP. Minocycline pleurodesis following simple aspiration is effective in preventing pneumothorax recurrence.

• Thoracoscopic bullectomy with mechanical or chemical pleurodesis is the preferred management in PSP patients with recurrent pneumothorax, persistent air leaks, bilateral pneumothorax or hemopneumothorax.

• Chemical pleurodesis is used to achieve symphysis between the two layers of pleura. Recent studies have found that chemical pleurodesis is also safe and effective in preventing pneumothorax recurrence in patients with a first episode of spontaneous pneumothorax or after thoracoscopic surgery for PSP.