What Does Thoracentesis Show?

Your doctor will send the fluid removed during thoracentesis for testing. It will be looked at for signs of heart failure, infection, cancer, or other conditions that may be causing the pleural effusion (the buildup of fluid between the lungs and chest wall).

Once the cause of the pleural effusion is known, your doctor will talk to you about a treatment plan. For example, if an infection is causing the excess fluid, you may need antibiotics to fight the infection. If the cause is heart failure, you will be treated for that condition.