Peritoneal lavage with povidone-iodine solution in experimentally induced peritonitis

Two experimental studies were carried out upon dogs to clarify the efficacy of peritoneal povidone-iodine lavage in peritonitis. With an experimental model of peritonitis which closely resembles the clinical situation, we found that peritoneal lavage with povidone-iodine was not more effective than other lavage regimens in decreasing bacterial colony counts and was associated with an early 100 per cent mortality. Renal function was not affected by the treatment with this antiseptic solution. However, we found a statistically significant superimposed metabolic acidosis in the peritonitis group treated with povidone-iodine when compared with the other groups, by means of a significant decrease in base excess, p less than 0.01, at the two hour postlavage measures. This metabolic acidosis was also observed in normal dogs undergoing peritoneal lavage with povidone-iodine, showing a significant decrease in serum bicarbonate level one hour, p less than 0.05, and three hours, p less than 0.01, three hours postlavage, when compared with a sham laparotomy group in the nonperitonitis study. This has not previously been experimentally investigated. In view of these results, we do not recommend the clinical use of povidone-iodine solution for peritoneal lavage in peritonitis.