Thoracentesis is done at a doctor's office or hospital. The entire procedure (including preparation) usually takes 10–15 minutes, but the needle or tube is in your chest for only a few minutes during that time. If you have a lot of fluid in your pleural space, the procedure may take up to 45 minutes.
You'll sit on the edge of a chair or exam table, lean forward, and rest your arms on a table. You'll be asked to not move, cough, or breathe deeply once the procedure begins.
Your doctor may use ultrasound to find the right place to insert the needle or tube. Ultrasound uses sound waves to create a picture of the structures in your body, such as your lungs.
Your doctor will clean the area on your skin where the needle or tube will be inserted. Then, he or she will inject medicine to numb the area. You may feel some stinging at this time.
Your doctor will insert the needle or tube between your ribs and into the pleural space (the space between the lungs and chest wall). You may feel some discomfort and pressure at this time.
Using the needle or tube, your doctor will draw out the excess fluid around your lungs. You may feel like coughing, and you may feel some chest pain.
Your doctor may take only the amount of fluid needed to find the cause of the pleural effusion. However, if you have a lot of fluid in your pleural space, he or she may take more. This helps the lungs expand and take in more air, which allows you to breathe easier.
Once the fluid is removed, your doctor will take out the needle or tube. He or she will place a small bandage on the site where the needle or tube was inserted.