Valva ileocaecalis: preservation during ileocolonic surgery employing a rodent experimental model.

Experimental and clinical data suggest that the valva ileocaecalis under neurogenic and hormonal influences, modulates antegrade and retrograde flow of succus entericus. A priori reasoning suggests that this function may influence nutrient absorption by and intraluminal endogenous microbial flora within the ileum. The hypothesis to be tested was, can anatomical and functional integrity of the valva ileocaecalis be preserved during the performance of a right hemicolectomy with reestablishment of intestinal continuity via a cecocolostomy? The methodology involved utilization of Lewis male rats weighing approximately 500 gm. General anesthesia was induced for all procedures. The animals were randomly assigned to three groups (10 animals/group): (A) sham operation; (B) pericecal dissection (preservation of the arteria et vena ileocolica); and (C) periileal dissection (ligation of the aforementioned vessels). Celiotomy was performed employing standard clean techniques, and was accompanied by a right hemicolectomy and an end-to-end or end-to-side cecocolostomy. Function of the heterotopic valva ileocaecalis was assessed 6-12 weeks post-operatively employing radiographic criteria (fluoroscopic analysis after intraluminal instillation of barium sulfate). Light microscopic analysis was performed subsequent to the radiographic studies. Periileal dissection associated with ligation of the arteria et vena ileocolica uniformly resulted in anastomotic disruption. Pericecal dissection associated with preservation of those vessels resulted in uniform anastomotic integrity, although two animals succumbed secondary to pneumonitis within 5 post-operative days. Radiographic analysis of the heterotopic valva ileocaecalis revealed intermittent antegrade and no retrograde flow of contrast material, which suggested functional integrity. Qualitative light microscopic analysis revealed architectural integrity.(ABSTRACT TRUNCATED AT 250 WORDS)