Thoracentesis is a procedure to remove fluid from the space between the lining of the outside of the lungs (pleura) and the wall of the chest.
Normally, there is little fluid (about 4 teaspoons!) in this cavity, or pleural space. A buildup of too much fluid between the layers of the pleura is called a pleural effusion. When extra fluid presses on the lungs, it can make it hard to breathe.
Why is thoracentesis performed?
Pleural effusion is very uncomfortable. The procedure is performed to relieve the symptoms of fluid buildup and increase patient comfort.
The collected fluid can be sent to the laboratory to be tested to determine the cause of the fluid building. This test is called pleural fluid analysis. Sometimes the procedure is performed for both patient comfort and test purposes.
Why is pleural fluid analysis done?
The test may be also performed for conditions such as bacterial infection, asbestos-related pleural effusion, drug reactions, collagen vascular disease, lung cancer, hemothorax, pancreatitis, pneumonia and pulmonary embolism, pulmonary veno-occlusive disease and thyroid disease.When a bacterial infection is suspected, a culture of the fluid is taken.
Abnormal results can be caused by such conditions at cancer, cirrhosis, infection, heart failure, inflammation, malnutrition and kidney disease.
How is the procedure performed?
There is no preparation for this test. As with most medical procedures, you will be asked to sign a consent form that outlines the benefits and risks of the procedure.
A check X-ray is taken before the procedure. Next, a small area of the skin on your back is sterilized, a local anesthetic is injected into the area to numb that portion of the body.
When numb, a needle, which serves to draw the excess fluid out, is placed through the skin and muscles of the chest wall into the pleural space (the space around the lungs). It is important to not cough, breathe deeply or move during the test.
There is generally a stinging sensation when the local anesthetic is injected. It is possible to feel pain or pressure when the needle is inserted in the pleural space. You should advise the provider if you experience shortness of breath or chest pain.
After the fluid has been removed, another chest X-ray is taken to compare the two images.
The procedure usually takes from 10 to 15 minutes. However, it may take longer if there is a lot of fluid to be removed. Generally, the patient is observed for a few hours.
Where is this procedure performed?
The procedure can be performed in a doctor’s office, the X-ray department of a hospital, in the emergency room, at your bedside in the hospital or in the interventional radiology suite at the hospital. RIA Endovascular interventional radiologists perform thoracentesis in the radiology suites in local hospitals. They use ultrasound to both access the fluid and avoid vital organs.
Are there risks to this procedure?
Usually, no serious problems occur. However, like most procedures, it is possible to have a complication. The following problems, which usually get better on their own, can occur. If they do not, you doctor would likely prescribe treatment.
- Pneumothorax – collapsed lung
- Pain, bruising, bleeding or infection where the needle or tube was inserted
- Injury to the liver or spleen (extremely rare)
How is treatment for the underlying condition determined?
Once the doctor receives the lab results, he or she can begin to plan treatment based on the results. For instance, an infection would require antibiotics. Results indicative of cancer, cirrhosis, infection, heart failure, inflammation, malnutrition or kidney disease would require different treatment paths.