Commercial peritoneal dialysis catheters work well, but over-the-needle catheters can be fenestrated and used with good results
for a diagnostic peritoneal lavage. Using a peritoneal dialysis catheter for abdominocentesis alone without lavage has been
shown to detect 1 to 4.4 ml of abdominal fluid/kg body weight.1 The peritoneal dialysis catheter's larger diameter and multiple side holes make occlusion with omentum or bowel less likely.
Using a 14-or 16-ga over-the-needle catheter with fenestrations can increase the surface area for drainage. The fenestrations
should be small and smooth and placed manually in a sterile manner by using a No. 10 scalpel blade. To avoid weakening the
catheter's integrity, don't create too many fenestrations or place them opposite each other on the catheter.
For the procedure, place the patient in left lateral recumbency, and use sedatives and analgesics for patient comfort and
restraint. Prepare the ventral abdomen with a wide surgical clip and an aseptic scrub centered on the umbilicus. Advance the
fenestrated, over-the-needle catheter completely off the stylet once the tip has penetrated the peritoneal cavity. Attach
a syringe to the catheter to obtain a sample. If no peritoneal fluid is obtained, infuse 22 ml/kg of warm, sterile 0.9% sodium
chloride solution by gravity through a drip set attached to the catheter. To distribute the saline solution throughout the
abdomen, gently massage the abdomen or roll the patient without dislodging the catheter. Either attach a syringe and gently
aspirate fluid from the catheter or allow gravity to fill the drip set and fluid bag. Usually, only small volumes of fluid
are obtained because of the wide dispersion throughout the abdomen. Submit any fluid obtained for biochemical and cytologic
evaluation, including culture and antimicrobial sensitivity testing.
Dr. Karl E. Jandrey, DVECC
1. Kolata RJ. Diagnostic abdominal paracentesis and lavage: experimental and clinical evaluations in the dog. J Am Vet Med Assoc 1976;168:697-699.