Clorhexidine as a factor that promotes peritoneal adhesions in rats with induced peritonitis

PURPOSE: To investigate the effects of chlorhexidine on the formation of adhesions and dilation of the colon at the oral end of anastomosis in the presence of peritonitis. METHODS: Peritonitis was induced in male Wistar rats by cecal ligation and puncture (CLP). Abdominal cavities were irrigated with tepid solutions containing 0.9% saline (SAL group; n=8) or 0.05% chlorhexidine (CHD group; n=8), after which colon anastomoses were performed. Control rats (n=8) were submitted to colon anastomoses but not to CLP. Animals were euthanised seven days after surgery and the incidence of adhesions, the degree of dilation of colon loops and an index were calculated to determine variables correlation. RESULTS: No animals exhibited macroscopic signs of residual peritonitis or abdominal abscesses. Adhesions were observed in 75% of control and 100% of SAL and CHD animals. Dilation of intestinal loops at the oral end of anastomosis was observed in control (50%), SAL (57.2%) and CHD (66.7%) animals. The calculated index was 1.25 in group A; 1.86 in group B; and 2.0 group C. CONCLUSION: Chlorhexidine promoted stronger adhesions and a greater dilatation of colonic loops than control group.

Clinical and histological responses to laparoscopically-induced peritonitis in rats / Resposta clínica e histológica à indução de peritonite via laparoscopia em ratos

PURPOSE: To evaluate the efficacy of inducing peritonitis in rats through laparoscopic cecal ligation (CL), by means of an elastic band. METHODS: Twelve Wistar rats were subjected to cecal ligated with an elastic band applied using a specially constructed applicator. In six of the animals (the CL group) the cecal sac was preserved intact whilst in the remaining animals (the CLP group) the sac was perforated with scissors. Clinical parameters, characteristics of the peritoneal cavity and cecum, and histological features of the cecal tissue were observed in all experimental animals 8 and 24 h after surgery. RESULTS: CLP animals exhibited at least one clinical sign of sepsis within the first 8 h of observation. The peritoneal liquid was observed to be clear in almost all members of the CLP. Polymorphonucleated cells were detected in the tunica serosa of the cecum of CLP animals. In contrast, all members of the CL group were alive after 24h, and of polymorphonucleated cells in the muscle layer of the cecal wall were observed. The presence of peritoneal liquid was not detected in CL animals. CONCLUSION: Although elastic ligation of the cecum was reproducible, puncture of the cecal sac was essential for induction of sepsis.

OBJETIVO: Avaliar a eficácia de induzir peritonite em ratos através da ligadura cecal laparoscópica (CL), por meio de banda elástica. MÉTODOS: Doze ratos Wistar foram submetidos a ligadura cecal com banda elástica aplicada com dispositivo especialmente construído para este fim. Em seis animais (grupo CL), a bolsa cecal foi mantida intacta, enquanto nos outros animais (grupo CLP), a bolsa foi perfurada com tesoura. Parâmetros clínicos, características da cavidade peritonial e ceco, e histologia do tecido cecal foram examinados em todos os animais 8 e 24 horas após a cirurgia. RESULTADOS: Os animais do grupo CLP apresentaram pelo menos um sinal clínico de sepses nas primeiras 8 h de observação. Líquido peritonial claro foi observado em quase todos os membros do grupo CLP. Leucócitos polimorfonucleares foram identificados na serosa do ceco dos animais do grupo CLP. Por outro lado, todos os animais do grupo CL estavam vivos após 24 h, e leucócitos polimorfonucleares estavam restritos à muscular própria. Presença de líquido peritonial não foi detectada nos animais do grupo CL. CONCLUSÃO: A ligadura elástica do ceco foi reprodutível e a secção da bolsa cecal foi essencial para a indução de sepse.