From Biology-Online Dictionary | Biology-Online Dictionary


noun, plural: paracenteses

A procedure in which a needle is used to puncture the abdomen, mainly to obtain body fluid sample for analysis or to drain off fluid to relieve pressure


Paracentesis is a procedure that involves the use of a needle to puncture the abdomen for body fluid sampling or for draining fluid from the abdomen. One of the major reasons for conducting this procedure is to relieve the abdomen from the pressure due to ascites. The liquid that accumulates in the abdomen is referred to as ascites. Ascites may be classified into three grades. Grade 1 is the mild form and would be detected via ultrasound or Ct. Grade 2 is visible and detected with flank bulging and shifting dullness. Grade 3 is the most visible type and positive to the fluid wave/thrill test.

One of the reasons that the ascites accumulate is linked to liver cirrhosis. The increased pressure in the hepatic portal vein leads to the fluid to seep out and accumulate in the peritoneal cavity. The ascites in this regard acts as transudates. Another possible cause of ascites is inflammation or malignancy. In this case, the ascites acts as exudates or secretions. Ascites as transudates differs from the one as exudates. Exudates have more protein content, more lactate dehydrogenase, and more white blood cells. Transudates are low in proteins and lactate dehydrogenase, and with fewer white blood cells.

Apart from relieving abdominal pressure from ascites, paracentesis is done to diagnose infections (e.g. abdominal TB) or malignancies (e.g. metastatic cancer).

Peritoneocentesis is a paracentesis wherein the peritoneal cavity is punctured in order to take or drain body fluid from the abdomen.


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