Effects of 5-fluorouracil on the healing of bowel anastomosis in rats.

This study looks at the effects of 5-Fluorouracil (5-FU) on surgical wound healing. A small bowel anastomosis was done 10 cm distal to the duodenum in rats. 5-FU was given by intramural infiltration on both sides of the suture line. Five, 10, and 20 mg of 5-FU were given in single doses. The control groups were given normal saline in the same manner. All groups were examined on days 4, 7, 8, and 12 postoperatively. The following methods were used to evaluate the anastomotic site: 1) bursting pressure measurements for tensile strength, 2) microangiography (micropaque), and 3) histopathologic sections. During the first 3 days postoperatively, the bowel had not healed sufficiently to permit significant bursting pressure measurements. Analysis of bursting pressure data and examination of the histopathologic sections showed no significant difference between the control groups and the 5-FU groups. Microangiography showed impaired dye distribution in the 5-FU groups during the first 4 to 6 days postoperatively. The control groups exhibited normal dye distribution. From day 7 on, the distribution in all groups became normal. Impaired dye distribution was the only measurable macroscopic change caused by intramural 5-FU administration. 5-FU injections had no apparent effect on anastomotic strength.