Paracentesis is a medical procedure involving the removal of excess fluid from the abdominal cavity, a condition called ascites. Fluid accumulation can occur due to various health issues. It is widely performed and generally considered safe.
Why Paracentesis is Performed
Paracentesis serves both diagnostic and therapeutic purposes. Diagnostic paracentesis involves removing a small amount of fluid for laboratory analysis. This analysis helps healthcare providers identify the underlying cause of the fluid buildup, which can include conditions such as liver cirrhosis, infections, or certain types of cancer.
Therapeutic paracentesis, conversely, aims to alleviate discomfort and symptoms caused by a large volume of abdominal fluid. Excessive fluid can lead to symptoms like abdominal pain, pressure, and shortness of breath due to pressure on the diaphragm. Draining the fluid can significantly improve these symptoms, enhancing a patient’s comfort and breathing. This procedure is often recommended when other treatments, such as diuretics, have not effectively managed the fluid accumulation.
Steps of the Paracentesis Procedure
Before a paracentesis, patients are typically asked to empty their bladder to prevent accidental puncture. The patient is then positioned comfortably, often lying on their back with the head slightly elevated, which allows the fluid to collect in the lower abdomen. The skin over the chosen insertion site on the abdomen is thoroughly cleaned with an antiseptic solution for sterility.
A local anesthetic is administered to numb the specific area where the needle will be inserted, to minimize discomfort. Patients may feel a brief sting or pressure as the numbing medication is injected. A thin needle, often with a catheter, is then carefully inserted through the numbed skin into the abdominal cavity. Ultrasound guidance is frequently used to pinpoint the fluid’s exact location and avoid blood vessels or other organs, enhancing safety and precision.
Once the catheter is correctly positioned, the excess fluid begins to drain into a collection bag or vacuum container. The amount of fluid removed varies depending on the purpose of the procedure, from a small sample for diagnostic tests to several liters for symptom relief. The process typically takes 20 to 45 minutes, depending on the volume drained. After fluid collection, the needle and catheter are removed, and pressure is applied before a bandage is placed.
What Happens After Paracentesis
Following a paracentesis, a dressing is applied to the insertion site, and vital signs are monitored typically for about an hour. Slight discomfort or minor clear fluid leakage from the puncture site is common, especially after large volume removal. This leakage typically lessens within one to two days.
The collected fluid is immediately sent to a laboratory for comprehensive analysis. This analysis provides crucial information for determining the underlying condition and guiding further treatment decisions. Key tests performed on the fluid include:
Cell count to identify white and red blood cells, which can indicate infection or bleeding.
Protein and albumin levels to differentiate between various causes of fluid buildup.
Culture to check for bacteria, helping diagnose infections like spontaneous bacterial peritonitis.
Cytology, the microscopic examination of cells, to detect abnormal cells that may suggest cancer.