A New Model for Studying Nutrition in Peritonitis

In guinea pigs fed ad libitum, controlled intraperitoneal infusion of bacteria by an implanted 7-day osmotic pump resulted in peritonitis or abscess formation with a 50% survival 14-18 days after pump implantation. Administration of 125 kcal/kg/day of a diet found to be optimal for burned guinea pigs by continuous pump controlled feedings via a previously placed gastrostomy was well-tolerated, with a 62.5% mortality by Day 17. Administration of only 100 kcal/kg/day caused weight loss of approximately 17% after 16 days, but fewer animals died (42.8%, p = NS). Feeding either 150 kcal/kg/day or 175 kcal/kg/day caused death in all 25 animals (p less than 0.001) and their survival time was slightly shortened (p = NS) when compared with animals receiving 100 or 125 kcal/kg/day. This is the first animal model of peritonitis that permits incisive dissection of the relative influences of dietary composition on outcome, because survival can be extended to 2 weeks or more in the presence of continuing sepsis.