Role of colonic bacteria in the pathophysiology of fecal peritonitis.

This study was designed to clarify the role of colonic bacteria in the reactions accompanying fecal peritonitis. Rats were subjected to septic or nonseptic peritonitis induced by fresh fecal suspensions or suspensions pretreated with heat or antibiotic. Measurements during 8 hr in rats with septic peritonitis recorded bacteremia, hypoglycemia dn progressive hemoconcentration, lactacidemia, and hypocapnea. Mortality was 100% by 24 hr. Nonseptic peritonitis produced significantly lesser degrees of hemoconcentration and hypocapnea. Plasma lactate remained in control ranges while plasma glucose concentrations increased slightly. Mortality was 5% in 24 hr. Parameters in control rats were stable over 8 hr. Hepatic oxygen supply was estimated in each group by multiple platinum wire electrodes. Severe hepatic hypoxia was recorded by 6 hr in rats with septic peritonitis. By contrast, nonseptic peritonitis caused a comparatively mild degree of hypoxia. The pathophysiologic developments in septic rats appear to be largely the result of hypovolemia induced by colonic bacteria. Administration of a colloid solution was effective in preventing its development.