<P> Blood also can collect in the pleural space . This is called hemothorax . The most common cause is injury to the chest from blunt force or surgery on the heart or chest . Hemothorax also can occur in people with lung or pleural cancer . </P> <P> Hemothorax can put pressure on the lung and force it to collapse . It also can cause shock, a state of hypoperfusion in which an insufficient amount of blood is able to reach the organs . </P> <P> Pleurisy and other disorders of the pleurae can be serious, depending on what caused them . Generally, pleurisy treatment has an excellent prognosis, but if left untreated it can cause severe complications . For example, a resulting pulmonary heart disease cor pulmonale, which manifests itself with an inflammation of the arms and legs, can lead to heart failure . If the conditions that caused the pleurisy or other pleural disorders were adequately diagnosed and treated early, one can expect a full recovery . Help of a pulmonologist (respiratory physician in the U.K. and Australia) may be enlisted to address the underlying cause and chart post-illness rehabilitation . </P>

Pain in back right side when i breathe