The effect of an intraluminal tube used as an internal drain on the healing of the rat colon.

The effect of an intraluminal tube on the healing of an inadequately constructed colonic anastomosis was evaluated. An anastomosis using a single suture was constructed in 78 rats divided into four experimental groups. In one, a latex tube was sited intraluminally at the level of the anastomosis and removed transanally after six days. In the second, a soft tube consisting of rat duodenum preserved in 5 percent formalin was similarly sited and allowed to pass spontaneously. In the third group, the formalin tube was placed outside the colon surrounding the anastomosis. The fourth group was a control. The mortality of the latex intraluminal tube group was 48 percent, the intraluminal duodenum in formalin group 29 percent (significantly less than the control group, P less than .02), the extraluminal tube around the anastomosis group 100 percent, and the control group 75 percent (P less than .02). There was no significant difference among the experimental groups in the mean breaking strength of the colonic anastomosis in the 28-day survivors.