Spontaneous pneumothorax

What is it

Spontaneous pneumothorax is a collection of air or gas in the chest that causes the lung to collapse without a traumatic injury to the chest. A primary spontaneous pneumothorax usually occurs at rest.

Symptom

• Chest pain on affected side 
• Dyspnea (shortness of breath)
• Cough
• Abnormal breathing movement
• Rapid respiratory rate

The major symptom is sudden chest pain with breathlessness. The pain may be either dull , sharp or stabbing. It begins suddenly and is worsened by breathing deeply or by coughing. It is often accompanied by rapid respiratory rate and abnormal breathing movement.

Diagnosis

In addition to history and PE, spontaneous pneumothorax is easily diagnosed by chest radiographs( chest film or CT ). 

Cause

Usually, the rupture of a small bleb or bullae (an air- or fluid-filled sac in the lung) causes primary spontaneous pneumothorax. Secondary spontaneous pneumothorax occurs in the setting of known lung disease, most often chronic obstructive pulmonary disease (COPD). Other lung diseases commonly associated with spontaneous pneumothorax include: tuberculosis, pneumonia, asthma, cystic fibrosis, lung cancer, and certain forms of interstitial lung disease.

Recurrence

If left untreated, recurrence rates of a spontaneous pneumothorax are high. It is reported that same side recurrence rates as high as 30% at six months and up to 50% at 2 years  without treatment.

How to treat

The first objective of treatment is to remove the air from the pleural space, allowing the lung to re-expand. Small pneumothoraces may resolve by themselves. Aspiration of air, through a catheter to a vacuum bottle may re-expand the lung. The placement of a chest tube between the ribs into the pleural space allows the evacuation of air, when simple aspiration is not successful, or the pneumothorax is large. Re-expansion of the lung may take several days with the chest tube left in place. 

The second is to prevent it from recurrence. Thoracoscopic surgery(VATS) is a unique way to definitively treat spontaneous pneumothorax. When the thoracoscopy used, magnified direct visualization of all lung surfaces can be performed to evaluate the lung for parenchymal disease. Techniques to detect air leaks, such as partial lung inflation and inflation with the lung immersed, can be used to help find small air leaks and bullae. When identified, these can be dealt with appropriately.

In general, we manage it in 2 ways:

Complete excision and stapling of the base of the bleb with an endoscopic linear stapling device or ligation of individual bullae with sutures. The later is cheaper because of using common thread.

 (Figures below shows how to ligate bullae with suture)

Another method to prevent recurrent spontaneous pneumothorax is to cause a permanent adhesion between the visceral pleura and the interior of the chest wall. This can be accomplished thoracoscopically by a wide variety of techniques and agents. Mechanical pleurodesis can be accomplished with direct physical trauma to the parietal pleura : Parietal pleurectomy. Chemical pleurodesis also can be introduced via the thoracoscope when appropriate,but is often used in the old patients with COPD.