The influence of methylene blue on the healing of intestinal anastomoses subjected to ischemia and reperfusion in rats.
OBJECTIVE
To investigate the influence of methylene blue, on the healing of intestinal anastomoses subjected to ischemia and reperfusion in rats.


METHODS
Forty-five rats divided into the following three groups were used: control (G1); ischemia without methylene blue (G2); and ischemia with methylene blue (G3). A laparotomy was performed and the cranial mesenteric artery isolated. Whereas the cranial artery was temporarily occluded for 45 minutes in groups G2 and G3, prior to enterotomy and intestinal anastomosis, in group G1 the enterotomy and intestinal anastomosis were performed without prior lesion. Afterwards, 2mL of 0.5% methylene blue were instilled in the peritoneal cavities of the animals in group G3, and 2mL of isotonic saline solution in the peritoneal cavities of the animals in group G2. After the reperfusion, an enterectomy and intestinal anastomosis were performed. After the animals had been sacrificed on the seventh day after the operation, the abdominal cavity was examined by resection of a segment of the intestine containing the anastomosis in order to measure its strength and for histopathological examination.


RESULTS
Free fluid or abscesses in the peritoneal cavity were rare. When inflammation was analyzed, the group subjected to ischemia without methylene blue had a higher score for mononuclear cells (p=0.021) and granulation tissue (p=0.044). No significant difference was observed in the density of type I or type III collagens.


CONCLUSIONS
The methylene blue did not show beneficial effect on the healing of intestinal anastomoses subjected to ischemia and reperfusion in rats.
Miranda
Eron Fabio
EF
PUC-PR, Paraná, Brazil. eronfm@brturbo.com.br
Greca
Fernando Hintz
FH
Noronha
Lucia
L
Kotze
Luiz Roberto
LR
Rubin
Michel Risnic
MR
D000714:Anastomosis, Surgical; D000818:Animals; D007422:Intestines / Q000098:blood supply / Q000601:surgery*; D007511:Ischemia / Q000188:drug therapy*; D008638:Mesenteric Arteries / Q000601:surgery; D008751:Methylene Blue / Q000494:pharmacology*; D023421:Models, Animal; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000188:drug therapy*; D014945:Wound Healing / Q000187:drug effects*
D008751:Methylene Blue