Pneumothorax classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Feham Tariq, MD [2], Hamid Qazi, MD, BSc [3]

Pneumothorax can be classified into tension and non-tension pneumothorax. A tension pneumothorax is an acute medical emergency as air accumulates rapidly in the pleural space with each breath. The increase in intrathoracic pressure results in massive shifting of the mediastinum away from the affected lung compressing intrathoracic vessels. Non-tension pneumothorax is of lesser severity because there is slower accumulation of air and therefore slower increase in air pressure in the pleural cavity. In primary spontaneous pneumothorax, it is usually characterized by a rupture of a bleb in the lung while secondary spontaneous pneumothorax mostly occurs due to chronic obstructive pulmonary disease (COPD). There are several diseases that may lead to secondary spontaneous pneumothorax including tuberculosis, pneumonia, asthma, cystic fibrosis, lung cancer, interstitial lung disease, and marfan’s syndrome.

Pneumothorax is divided mainly into tension and non-tension pneumothorax:^[1]

• A tension pneumothorax is an acute medical emergency as air accumulates rapidly in the pleural space with each breath. The increase in intrathoracic pressure results in massive shifting of the mediastinum away from the affected lung compressing intrathoracic vessels.
• By contrast, non-tension pneumothorax is of lesser severity because there is slower accumulation of air and therefore slower increase in air pressure in the pleural cavity.

The accumulation of blood in the thoracic cavity (hemothorax) exacerbates the problem, creating a pneumohemothorax.

• Spontaneous pneumothorax can be classified as primary spontaneous pneumothorax and secondary spontaneous pneumothorax. In primary spontaneous pneumothorax, it is usually characterized by a rupture of a bleb in the lung while secondary spontaneous pneumothorax mostly occurs due to chronic obstructive pulmonary disease (COPD).

• A primary spontaneous pneumothorax may occur without either trauma to the chest or any kind of blast injury. This type of pneumothorax is caused when a bleb (an imperfection in the lining of the lung) bursts causing the lung to deflate. If a patient suffers two or more instances of a spontaneous pneumothorax, surgeons often recommend a bullectomy and pleurectomy.
• Primary spontaneous pneumothorax is most evident to people without any previous history of lung disease and in tall, thin men whose age is between 20 to 40 years old. But it can often occur in teenagers and young adults.

• A known lung disease is present in secondary spontaneous pneumothorax.^[2] The most common cause is chronic obstructive pulmonary disease (COPD). However, there are several diseases that may lead to secondary spontaneous pneumothorax:
  • COPD
  • Tuberculosis
  • Pneumonia
  • Asthma
  • Cystic fibrosis
  • Lung cancer
  • Interstitial lung disease
  • Marfan’s syndrome