Effect of povidone iodine and chlorhexidine on the mortality and bacterial clearance in the abdominal cavity of peritonitis rats.

Peritonitis was induced in Wistar rats by intraperitoneal inoculation of pure Escherichia coli. The mortality rate in the untreated control group was 36% (18/50). Rats in which 2 ml 1% povidone iodine had been injected intraperitoneally 5 min after the bacterial challenge, had a significantly increased mortality rate (43/50, 86%) (p less than 0.01). When the same experiment was done with 2 ml of 0.05% chlorhexidine the mortality rate decreased significantly to 16% (8/50) (p less than 0.05). Povidone iodine did not have any bactericidal effect; on the contrary, the number of colonies of bacteria had increased in all the animals 12 and 24 hours after challenge. Chlorhexidine, on the other hand, had sufficient bactericidal effect to cause a progressive decrease in the concentration of intraperitoneal bacteria.