The second STEP: the feasibility of repeat serial transverse enteroplasty.

BACKGROUND Serial transverse enteroplasty (STEP) lengthens and tapers dilated bowel. Redilation of the STEP segment occurs in some patients with intestinal failure. The feasibility of a repeat STEP procedure in a pig model is evaluated. METHODS Six pigs underwent reversal of an intestinal segment distal to the ligament of Treitz. At 6-week intervals after reversal, each animal had 2 STEP procedures on the bowel proximal to the reversed segment. Necropsy was performed up to 6 weeks after repeat STEP. RESULTS Bowel length increased by 11.3 +/- 3.9 cm and bowel diameter decreased from a mean of 5.3 +/- 0.8 to 1.8 +/- 0.4 cm (P < .0001) after the first STEP. After repeat STEP, bowel length increased by 16.7 +/- 13.3 cm (P < .01), and the bowel was tapered from a mean of 5.4 +/- 0.9 to 2.2 +/- 0.4 cm (P < .01). Five pigs did well after repeat STEP, and 1 pig had early necropsy for bowel obstruction. None had histologic evidence of bowel ischemia in the repeat STEP segment. CONCLUSIONS A second STEP operation is feasible in a pig model and may be considered to optimize bowel length and function in select patients with intestinal failure.