Patient education: Thoracentesis (The Basics)

What is thoracentesis? — Thoracentesis is a procedure to get a sample of fluid from the space around the lungs. A doctor uses a needle to remove the fluid.

The area around the lungs is called the "pleural space." If fluid builds up in the pleural space, the lungs do not have as much room to expand. This is called a "pleural effusion" (figure 1). It can cause symptoms like chest pain and trouble breathing.

A thoracentesis can be done for 2 reasons:

●To help figure out what is causing the fluid buildup around your lungs. The doctor will remove a small amount of fluid and send it to a lab for testing.

●To remove a larger amount of fluid to help you breathe more easily

How do I prepare for thoracentesis? — Most of the time, you do not need to do anything special to prepare for thoracentesis. Ask the doctor or nurse if you have questions or if there is anything you do not understand.

This procedure can be done in a doctor's office or in your room if you are in the hospital.

Before your procedure, your doctor will do an exam. They might have you get tests, such as:

●Imaging tests, such as an X-ray or ultrasound of your chest – Imaging tests create pictures of the inside of the body.

●Lab tests

Your doctor will also ask you about your "health history." This involves asking you questions about any health problems you have or had in the past, past surgeries, and any medicines you take. Tell them about:

●Any medicines you are taking – This includes any prescription or "over-the-counter" medicines you use, plus any herbal supplements you take. It helps to write down and bring a list of any medicines you take, or bring a bag with all of your medicines with you.

●Any allergies you have

●Any bleeding problems you have – Certain medicines, including some herbs and supplements, can increase the risk of bleeding. Some health conditions also increase this risk.

What happens during thoracentesis? — When it is time for the procedure:

●The staff will help you get into a position that will let the doctor get to the fluid around your lung. Most of the time, you will be sitting up.

●In most cases, the doctor will use an ultrasound to help decide where to place the needle. Depending on where the fluid is, this can be in your chest, back, side, or armpit.

●The doctor will clean your skin and give you a small amount of numbing medicine between your ribs. This will help with pain during the procedure.

●The doctors and nurses will monitor your breathing during the procedure. They might also monitor your blood pressure and heart rate.

●The doctor will make a small cut, or "incision," in the skin. Then, they will use a thin tube called a "catheter" to remove fluid from around your lung. Sometimes, they will use ultrasound to help guide the catheter into the right position.

●The doctor will drain some fluid by pulling back on the plunger of a syringe. In some cases, they will attach the needle to tubing to let the fluid drain into a bottle or bag. They might send some of the fluid to the lab for testing.

●The doctor will have you breathe out as they remove the catheter. They will cover the area with a clean bandage.

What happens after thoracentesis? — After your procedure, the staff will watch you closely for a short time. If you had a lot of fluid removed, the doctor might order special IV fluids to help your blood pressure. The doctor might also order a chest X-ray to see if there is any fluid left around your lung.

If you take an "anticoagulant" (medicine to help prevent blood clots), the doctor will talk with you about when it is safe for you to start taking it again.

What are the risks of thoracentesis? — Your doctor will talk to you about all of the possible risks, and answer your questions. Possible risks include:

●Pain

●Feeling faint

●Bleeding

●Infection

●Collapsed lung ("pneumothorax")

●Injury to the liver, heart, or spleen

●Fluid in the lung ("pulmonary edema")

How do I care for myself at home? — Ask the doctor or nurse what you should do when you go home. Make sure that you understand exactly what you need to do to care for yourself. Ask questions if there is anything you do not understand.

You should also:

●Keep your incision dry and covered with a bandage for the first 1 to 2 days. Your doctor or nurse will tell you exactly how long to keep your incision dry.

•Once you no longer need to keep your incision dry, gently wash it with soap and water whenever you take a shower. Do not put your incision underwater, such as in a bath, pool, or lake. This can slow healing and raise your chance of getting an infection.

•After you wash your incision, pat it dry. Your doctor or nurse will tell you if you need to put an antibiotic ointment on the incision. They will also tell you if you need to cover your incision with a bandage or gauze.

●Always wash your hands before and after you touch your incision or bandage.

What follow-up care do I need? — The doctor will want to see you again after the procedure to check on your progress. Go to these appointments.

When should I call the doctor? — Call for advice if:

●You have a fever of 100.4°F (38°C) or higher, or chills.

●You have redness or swelling around the thoracentesis area.

●You have pain when you take a deep breath.

●You have trouble breathing.

●You cough up blood.

More on this topic

Patient education: Pleural effusion (The Basics)
Patient education: Pleuritic chest pain (The Basics)
Patient education: Pneumothorax (collapsed lung) (The Basics)

Patient education: Thoracentesis (Beyond the Basics)