Pleura is made of a thin membrane that covers the surface of the lungs as well as the inside of the chest wall thus creating a virtual space called the pleural space. It is normal for this space to have some fluid (about 10 to 20 ml) as this allows the lungs to move smoothly within the chest cavity while you breathe. In some cases, excess fluid builds up in the pleural space. Thus pleural effusion is characterized by an abnormal amount of fluid around the lungs.

Pleural effusion may result from two main mechanisms: one is called transudative and produced by fluid pushed through small vessels mainly due to abnormal circulation within these vessels, the other is called exudative and produced by the alteration of the neighboring tissue, or the membrane itself, and caused by inflammation or infiltration by tumor cells. Keep reading to learn more about the causes, symptoms, and treatments for this medical condition.

1.  Transudative Pleural Effusion

This type of pleural effusion occurs when liquid leaks across a normal pleura. The condition creates only slightly more fluid than normal, so it rarely needs to be drained.

Congestive heart failure is the most common cause of transudative pleural effusion. However, liver or kidney disease can also cause fluids to build up in the body and leak into the pleural space.