Simple procedures for complicated cases (Proceedings)
Nov 01, 2009
CVC IN SAN DIEGO PROCEEDINGS
Indications include traumatic reticuloperitonitis (TRP), abomasal ulcer, peritonitis, uroperitoneum, chronic weight loss, abdominal mass. Three sites are recommended. The right ventral flank in front of udder just medial or lateral to caudal superficial epigastric vein (milk vein), is the site most likely site to yield some fluid. This is the preferred site for routine abdominocentesis. Between the xiphoid and umbilicus to the right of midline is the best site when abomasal ulcers suspected. Just behind xiphoid is the best site best when reticulitis is suspected. The use of ultrasonography simplifies the choice of abdominocentesis site. The supplies & equipment needed includes an 18 gauge 1.5 inch (or longer) needle, or a teat cannula and #10 blade, and a 2 ml EDTA blood tube. The technique is simple. Restraint is applied in the form of a tail jack. When inserting the needle, rest the hand on abdominal wall and use steady, firm pressure until the needle pops into abdomen. Stop. Wait. If no fluid comes out, spin the needle. The needle may move as the gut moves. If no fluid comes out, advance or retract needle. Be patient.
Interpretation: Only about half of attempts yield fluid. A few drops to a few milliliters are normal. Copious fluid is abnormal. Normal fluid has a total protein < 2 g/dl, and white cells (most of which should be mononuclears) < 5,000/microliter . Peritoneal creatinine twice the serum creatinine indicates uroperitoneum.
Cerebrospinal fluid aspiration
Interpretation - The sample should be at the lab in a few hours but if refrigerated it can be preserved longer. On gross visual examination, the sample should be crystal clear. If uniformly reddish, this indicates hemorrhage (traumatic or iatrogenic). Sometimes microscopic evaluation can distinguish between the two. If the fluid is cloudy, it may indicate meningitis. In severe cases of meningitis, the CSF may clot. A direct smear should contain almost no cells if normal. In bacterial meningitis is present, neutrophils predominate and maybe in sufficient quantity to be seen on a direct smear.