New idea of intestinal lengthening and tailoring

Both the Bianchi and the serial transverse enteroplasty (STEP) procedure have been reported to be successful in short bowel syndrome, but both have their limitations. The Bianchi technique is surgically challenging and can only tailor the diameter to half and double the length. The STEP procedure is easy, adjustable, but it changes the orientation of the muscle fibres making the circular; longitudinal and the longitudinal; circular. We have created a model to test our idea of Spiral Intestinal Lengthening and Tailoring (SILT).

A double layer intestinal simulator was used as the bowel model. The orientation of the circular muscle fibres was marked. The simulator was cut spirally at a 45° and 60° angle, stretched longitudinally and retubularised. The procedure was adapted to porcine small bowel ex vivo and mucosal microcirculation was observed in three separate points by intravital videomicroscopy in vivo.

The simulator was lengthened by 60% and the diameter was tailored by 33% using the 45° spiral cut, 73% lengthening and 44% tailoring was achieved at 60°. The circular muscle fibres showed oblique orientation. The porcine bowel was lengthened by 136 ± 21% and the diameter was tailored by 56 ± 8%. The linear regression analysis of variants showed significant linear regression R = 0.9689 (R(2) = 0.9388), p = 0.0014. The angle of the spiral cut (α) showed the relation: α ≥ 90-arc sin R(2)/R(1). (R(1) is the radius of the original segment and R(2) the desired radius of the tailored and lengthened bowel). The bowel remained viable macroscopically 90 min after the procedure. The median red blood cell velocity reduced from 570 (control) to 558 μm s(-1) in point 1, to 382 μm s(-1) in point 2, and to 482 μm s(-1) in point 3. Oscillation of the capillary flow has not been observed.

The SILT may be an easy, more physiological and adjustable alternative to the existing techniques.