Effect of pentoxifylline on the healing of ischemic colorectal anastomoses.

PURPOSE: The aim of this study was to evaluate the effect of pentoxifylline on the healing of experimental ischemic colorectal anastomoses.

METHODS

Ninety-three Wistar rats were randomized into three groups (n = 31) and underwent resection of a colonic segment at the colorectal junction. Group A rats received standard end-to-end anastomoses. Ischemic anastomoses were performed in Groups B and C rats by coagulating mesocolon vessels 2 cm along each anastomotic end. Group C rats were treated with intraperitoneal injection of pentoxifylline. Wound complications, intra-abdominal abscesses, intraperitoneal adhesions, and anastomotic leaks and stenosis were recorded. Bursting pressure and tension were calculated. Histologic examination of the anastomosis was also performed.

RESULTS

Ischemia increased wound and intra-abdominal infections, adhesion formation, and anastomotic stenosis. Anastomotic leakage was significantly higher in Group B (45.2 percent) than in Group A (9.7 percent). Bursting pressure and tension were significantly lower in Group B (118.19 mmHg and 48.43 N/m) than in Group A (191.84 mmHg and 86.82 N/m). There was evidence for decreased perianastomotic fibrosis and neutrophils presence after induced ischemia and a strong tendency to reduced neovascularization. Pentoxifylline administration ameliorated the effects of ischemia, reducing wound and intra-abdominal infections, adhesion formation, and leaks (16.1 percent). Anastomotic strength increased (bursting pressure and tension of 205.55 mmHg and 87.68 N/m, respectively). Treated Group C had significantly higher neutrophils infiltration and fibrosis formation and a strong tendency to increased neovascularization compared with Group B.

CONCLUSIONS

Selective anastomotic devascularization induces ischemia and impairs experimental anastomotic healing, increasing leakage rate. These effects may be ameliorated by pentoxifylline administration.