Response of pony peritoneum to four peritoneal lavage solutions.

Peritoneal lavage was performed on ponies to determine the effect on peritoneal surfaces. Lavage solution (20 L) was introduced into each pony's peritoneal cavity through catheters placed in the paralumbar fossa, and the solution was removed by drainage from the ventral portion of the abdomen. Six ponies each were lavaged with sterile saline (0.9% NaCl) solution, sterile saline solution containing 5 X 10(6) U of potassium penicillin and 3 g of neomycin or povidone-iodine diluted to 3% by volume with sterile saline solution, and 3 ponies were lavaged with povidone-iodine diluted to 10% with sterile saline solution. Peritoneal lavage catheters were inserted in 3 control ponies, but lavage fluids were not administered. Peritoneal fluid specimens were collected at 6, 24, 48, and 96 hours after lavage. Nucleated cell counts, RBC counts, total protein determinations, and cytologic analysis were performed. The ponies were euthanatized at 96 hours, and representative sections of the peritoneum were examined. Lavage with saline solution and saline solution with antibiotics induced a mild, transient inflammatory response in the peritoneal fluid, with minimal or no changes observed at necropsy. Solutions containing povidone-iodine induced chemical peritonitis, which was severe in ponies lavaged with 10% povidone-iodine solution. Peritoneal lavage with povidone-iodine solutions as dilute as 3% cannot be accomplished without causing inflammation of peritoneal surfaces.