Intravenous butyrate and healing of colonic anastomoses in the rat.

PURPOSE

Intracolonic infusions of short chain fatty acids promote healing of colonic anastomoses. Because the intravenous route may have wider clinical application, we studied the effect of intravenous n-butyrate on the mechanical strength of colonic anastomoses in the rat.

METHODS

After placement of an indwelling intravenous catheter, the descending colon was transected and an anastomosis was performed. Rats were then randomized to receive total parenteral nutrition (TPN group; n = 15) or total parenteral nutrition plus 130 mM/l of n-butyrate (TPN+BUT group; n = 13). On the fifth postoperative day, bursting pressure and bowel wall tension of the anastomoses were measured in situ. Anastomotic tissues were analyzed for hydroxyproline.

RESULTS

The TPN+BUT group had a significantly higher bursting pressure (107.5 +/- 30.3 vs. 83 +/- 41.0 mmHg; P = 0.04) and bowel wall tension (20.7 +/- 7.6 vs. 14.1 +/- 9.9 Newton; P = 0.03). Tissue hydroxyproline was not different between the two groups (TPN, 45.8 +/- 9.2, and TPN+BUT, 47.9 +/- 2.9 microg/mg tissue nitrogen).

CONCLUSIONS

We conclude that intravenous butyrate improves mechanical strength of a colonic anastomosis without a detectable change in total collagen content.