A series of extra tests like X-rays, CT scans, and pleural fluid examination will be required to understand the root of the condition and see if the patient is suffering from transudative or exudative pleural effusion. X-rays will determine the areas in the lungs that are affected by pleural effusion. These will be highlighted in a whiter tint.

The CT scans complement this first examination by determining the effusion’s potential cause. Further investigation implies the fluid’s analysis: through thoracentesis, the fluid is removed from the pleural space and sent to the laboratory for testing. The results thus obtained, together with the rest of the necessary blood analysis will determine the condition’s typology and evolution.