What is diagnostic paracentesis?
Diagnostic paracentesis is a procedure that enables the extraction of peritoneal fluid, namely the intra-peritoneal deposit that accumulates as a result of certain diseases, referred to as ascites (liver diseases and neoplastic diseases). The fluid is then sent to the laboratory for analysis.
What is the purpose of diagnostic paracentesis?
The main reasons to perform diagnostic paracentesis include analysis and removal of the liquid deposit, especially fluid that accumulates in the patient’s abdomen by reducing the discomfort and pressure caused by ascites and help the patient breath better. Other reasons to perform a diagnostic paracentesis include diagnosing metastatic cancer, diagnosing spontaneous bacterial peritonitis and other infections, and to diagnose blood in peritoneal space after a trauma.
Standard of preparation
In general, diagnostic paracentesis does not require specific preparation in addition to the preventive emptying of the bladder and performing routine blood tests prior to the procedure in order to monitor coagulation parameters.
Patients who are pregnant, who are taking medications or who are allergic to any other medications (including anaesthetics) must disclose that information to the medical staff. Moreover, patients should also disclose if they have any bleeding problems or if they are taking any antiplatelet agents.
Which patients can undergo diagnostic paracentesis?
Diagnostic paracentesis is indicated in patients who experience a new onset of ascites. In this case, the paracentesis is used to evaluate the fluid and help determine the etiology of the ascites and differentiate transudate from exudate ascites, as well as detect the presence of cancerous cells or address other concerns. The procedure is also indicated for patients with a suspected, spontaneous or secondary bacterial peritonitis.
On the other hand, diagnostic paracentesis is contraindicated in people with an acute abdomen that requires surgery to correct, and also in cases where the patients are taking anticoagulants or aspirin. Other contraindications include, obesity, pregnancy, distended bowl, distended urinary bladder, abdominal wall cellulitis, and intra-abdominal adhesions.
Is diagnostic paracentesis dangerous and/or painful?
The insertion of the needle into the abdomen is slightly painful; however, the procedure involves the use of an anaesthetic, which helps with the pain. In some cases, there are rare but potential risks such as perforation of the bladder, the intestine or a blood vessel, which lead to another risk of haemorrhage. Some complications associated with diagnostic paracentesis may include persistent leak from the puncture site, wound infection, abdominal wall hematoma or failure to collect peritoneal fluid.
How does the diagnostic paracentesis work?
The procedure is performed while the patient is sitting or lying on his back with his head slightly elevated. The doctor disinfects the area where the needle needs to be inserted, then administers anaesthesia and proceeds to the insertion of the needle through the use of an ultrasound. The average duration of the procedure is approximately 20 to 30 minutes, during which the patient must remain still unless otherwise instructed by the medical staff. At the end of the diagnostic paracentesis, the examined area is bandaged and the patient is kept under observation for about an hour.