Reasons, Preparation & Procedure of Ascitic Fluid Analysis

Submitted on March 27, 2012

What is Ascitic Fluid Analysis?

An ascitic fluid analysis is a test that is conducted on the peritoneal fluid during a case of ascites. This is a symptom of a bigger disease, which could be heart disease that causes edema, liver cirrhosis, and even hepatic vein blockages or occlusions. The test is conducted using a procedure that is similar to a test done in pregnant women called the amniocentesis test. The difference being that instead of analyzing the amniotic fluid in the uterus, the peritoneal fluid is checked. The test and analysis of ascitic fluid is called the SAAG or Serum Ascitic Albumin Gradient. This is a scale of measurement that deducts the amount of serum albumin from the amount of ascitec albumin. This value will determine the exact root cause and treatment.

Reason Why It is Done

The ascites fluid analysis is done to ascertain where the exact root cause of a problem of ascites is originating from. This is because the problem could be caused due to problems with the liver and heart or the problem could also be caused by kidney trouble. The level of protein in the fluid is measured and this will establish cause and treatment.


The peritoneal fluid test is done using a process similar to amniocentesis called paracentesis. In this procedure a local anesthetic is applied to the area of operation and then a catheter is routed from the skin into the peritoneal cavity. As soon as this is done, the peritoneal fluid will start to flow out. In the most extreme cases, nearly 25 liters of liquid can result. The fluid is then sent for an analysis for albumin content. The levels of serum albumin are subtracted from the peritoneal fluid albumin count and the count is then taken. If the values indicate a high gradient this means that there is portal hypertension causing fluid to leak from the portal veins. Protein content greater than 2.5 indicates heart failure is imminent and less than 2.5m cirrhosis of the liver. A low gradient indicates infection and some problems with the kidneys.


There is no preparation that needs to be done for the test though it is advisable to empty your bladder before coming for the test purely because this is a lengthy test. Also inform your doctor about any blood pressure problems or antihypertensive medication that you are currently on. Do not consume alcohol before the test.