Thoracentesis is generally a safe procedure. A
chest X-ray may be done right after the procedure to make sure that no
complications have occurred. Complications may include:
A partial collapse of the lung (
pneumothorax). This may occur if the needle used to
remove the pleural fluid punctures the lung, allowing air to flow into the
Pulmonary edema, which may occur if a
large amount of fluid is removed. Infection and
Damage to the liver or spleen, though this is
Thoracentesis is a procedure to remove
fluid from the space between the lungs and the chest wall called the pleural
space. Results from a lab are usually available in 1 to 2 working days. If the
fluid is being tested for an infection, such as
tuberculosis, results may not be available for several
A small amount of clear,
colorless, or pale yellow pleural fluid, usually less than
20 mL (0.7 fl oz), is normally
present. No infection, inflammation, or cancer is found.
A large amount of pleural
fluid is present.
Fluid may be labeled as either
a transudate or an exudate. The difference between these two types of fluid has
to do with the amount of protein and other substances found in the
A transudate has a low
white blood cell (WBC) count, a low lactate
dehydrogenase (LDH) enzyme level, and a low protein level. A transudate may be
heart failure, or
nephrotic syndrome. An exudate may be
caused by diseases, such as infection (
chest injury, cancer,
autoimmune disease, or a
pulmonary embolism (PE).
If an infection is present, the
exudate will have a high WBC count, a high LDH enzyme level, a high protein
level, and bacteria or other infectious organisms. If cancer is
present, the exudate will have a high WBC count (often
lymphocytes), a high LDH enzyme level, and a high
protein level. Abnormal cells may also be present. If a pulmonary
embolism is present, the exudate will have a low WBC count and large numbers of
red blood cells.
WebMD Medical Reference from Healthwise
September 09, 2014
This information is not intended to replace the advice of a doctor.
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