Thoracentesis: Overview
Thoracentesis is a procedure to remove fluid from the space between the lungs and the chest wall called the pleural space. It is done with a needle (and sometimes a plastic catheter) inserted through the chest wall. Ultrasound pictures are often used to guide the placement of the needle. This pleural fluid may be sent to a lab to determine what may be causing the fluid to build up in the pleural space.
Normally only a small amount of pleural fluid is present in the pleural space. A buildup of excess pleural fluid (pleural effusion) may be caused by many conditions, such as infection, inflammation, heart failure, or cancer. If a large amount of fluid is present, it may be hard to breathe. Fluid inside the pleural space may be found during a physical examination and is usually confirmed by a chest X-ray.
Why is a thoracentesis done?
Thoracentesis may be done to:
- Find the cause of excess pleural fluid (pleural effusion).
- Relieve shortness of breath and pain caused by a pleural effusion.
How is a thoracentesis done?
This procedure may be done in your doctor's office, in the X-ray department of a hospital, in an emergency room, or at your bedside in the hospital.
You will need to take off all or most of your clothes (you may be allowed to keep on your underwear if it does not interfere with the procedure). You will be given a cloth or paper covering to use during the procedure. During the procedure, you will be seated but leaning forward on a padded bedside table. X-rays or an ultrasound may be used to locate the fluid in your chest.
The needle site between your ribs will be cleaned with an antiseptic solution. Your doctor will give you a local anesthetic in your chest wall so you won't feel any pain when the longer needle that withdraws the fluid is inserted. When the area is numb, your doctor will insert the needle to where the fluid has collected (pleural space). You may feel some mild pain or pressure as the needle enters the pleural space.
Your doctor will use a syringe to remove a sample of fluid. If larger amounts of pleural fluid are removed, a small tube attached to a vacuum bottle is used. Your doctor will send the fluid to the lab. After the fluid is removed, the needle or small tube is removed. Then a bandage is put on the site.
After the test
An X-ray may be taken right after the procedure to make sure that no complications have occurred.
After thoracentesis: When to call
Call 911 anytime you think you may need emergency care. For example, call if:
- You passed out (lost consciousness).
- You have severe trouble breathing.
- You have sudden chest pain and shortness of breath, or you cough up blood.
Call your doctor now or seek immediate medical care if:
- You have shortness of breath that is new or getting worse.
- You have new or worse pain in your chest, especially when you take a deep breath.
- You are sick to your stomach or cannot keep fluids down.
- You have a fever over 100°F.
- Bright red blood has soaked through the bandage over your puncture site.
- You have signs of infection, such as:
- Increased pain, swelling, warmth, or redness.
- Red streaks leading from the puncture site.
- Pus draining from the puncture site.
- Swollen lymph nodes in your neck, armpits, or groin.
- A fever.
- You cough up a lot more mucus than normal, or your mucus changes color.
Watch closely for changes in your health, and be sure to contact your doctor if you have any problems.
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