Thoracentesis is a medical procedure that involves removing fluid or air from the pleural space, which is the area between the lungs and chest wall. It’s also known as a pleural tap, needle thoracostomy, or needle decompression. 

Thoracentesis is used for diagnostic or therapeutic purposes, such as:
  • Removing excess fluid

    When too much fluid builds up in the pleural space, it’s called a pleural effusion. This can make it difficult to breathe and reduce lung function. Thoracentesis can remove the excess fluid and relieve pressure. 

  • Diagnosing health problems

    The fluid sample collected during a thoracentesis can be tested in a lab to help determine the cause of the pleural effusion. This can help diagnose conditions such as congestive heart failure, viral infections, and some types of cancer. 

Thoracentesis is a common, low-risk procedure. During the procedure, you’ll feel a slight pinch when the nurse inserts the IV line and injects the local anesthetic. You might also feel pressure when the catheter is inserted, or a pulling sensation when the fluid is removed. You should remain still and avoid coughing or breathing deeply during the procedure. 

After the procedure, a chest x-ray or ultrasound is usually performed to check for complications.