Enteral and intraluminal short-chain fatty acids improves ischemic left colonic anastomotic healing in the rat

This study assessed the effect of short-chain fatty acids (SCFAs) on the healing of ischemic colonic anastomosis and compared the enteral and intraluminal (transrectal) forms of SCFAs in the same study. Left colonic ischemia was induced and a 1-cm left colon resection 2-4 cm above the peritoneal reflection was performed through a midline incision. In all, 160 rats were divided into eight groups: a control group, an ischemia group, a transrectal SCFAs group, an ischemia + transrectal SCFAs group, an enteral guar gum group, an ischemia + enteral guar gum group, an ischemia + enteral sham group, and a control + enteral sham group. The animals in each group were anesthetized again on day 4 or 7 after the operation for in vivo analytic procedures. Wound complications, intestinal obstructions, and anastomotic complications were recorded. Periperitoneal adhesions were graded. The strength of each anastomosis was assessed by measuring its bursting pressure. There were significantly more dense intra-abdominal adhesions in the ischemic group and ischemia + enteral sham group. Five animals in the ischemia group, six in the ischemia + enteral sham group, and one in each of the control and ischemia + transrectal SCFA groups developed anastomotic dehiscence. The median bursting pressures were significantly lower in the ischemic group and in the ischemia + enteral sham group on the 4 day and 7 days. Deleterious effects of ischemia on left colonic anastomotic healing were significantly prevented by the administration of either 7 days' pretreatment with enteral guar gum or the intraluminal instillation of SCFAs. There were no significant differences between enteral and intraluminal SCFA groups.