Pleural fluid aspiration; Pleural tap
Normally the pleural cavity contains only a very small amount of fluid.
The analysis of the fluid will indicate possible causes of pleural effusion such as infection, cancer, heart failure, cirrhosis, and kidney disease. If infection is suspected, a culture of the fluid is often done to determine whether microorganisms are present and if so, to identify them.
Additional conditions under which the test may be performed include the following: