A primary pneumothorax most often occurs when an apical subpleural bleb ruptures. Smoking increases the risk of a first spontaneous pneumothorax by 9 fold in women and 22 fold in men. The most common symptoms are chest pain on the side of the pneumothorax and dyspnea. This is not usually a life threatening condition unless tension develops. Clinical manifestations are more severe than with primary pneumothorax.
Dyspnea is typically more pronounced, even with the same degree of collapse.
The risk is greatest in the first month following the initial episode, and is much higher in secondary than primary cases. Treatment Treatment for spontaneous pneumothorax include observation, supplemental oxygen, aspiration, tube thoracostomy, chemical pleurodesis, or mechanical pleurodesis. When a bleb ruptures, air escapes from the lung into the pleural space. Because nitrogen is fairly diffusable across cell membranes, the pneumothorax will eventually spontaneously resorb. The administration of supplemental oxygen accelerates the rate of absorption of pleural air by altering the gradient of oxygen across the visceral pleura.