The second STEP: the feasibility of repeat serial transverse enteroplasty
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Published on: February 12, 2022
Hannah Piper1, Biren P Modi, Heung Bae Kim
1Department of Surgery, Children's Hospital Boston and the Harvard Center for Minimally Invasive Surgery, Harvard Medical School, Boston, MA 02115, USA.
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.