To drain large amounts of pleural fluid. A sample of the pleural fluid is analyzed in the lab for the presence of certain cells, sugar content, protein content, and other substances. Preparation You remove all clothing from the waist up and don a hospital gown. The doctor examines your chest to locate excess pleural fluid. Ultrasound or a CT scan may be used if localization is difficult or if the amount of fluid is small.
Local anesthesia is administered at the site of the test.
If there is fluid in this space, a sample can then be withdrawn for laboratory analysis. The sample is sent to a laboratory for analysis. After the test Pressure is applied to the puncture site to prevent bleeding. Factors affecting results Bleeding from the puncture site may interfere with analysis of the sample. The number and type of cells in the fluid, as well as the levels of glucose, acid, and various proteins, help establish whether the excess fluid is a result of infection, cancer, or other lung disease, or a complication of another disease such as congestive heart failure.