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426 Short Bowel Syndrome

Adaptation is driven by the increased load of fatty acids, Other medications used are cholestyramine to reduce the irritant
carbohydrates, and proteins on the enteroglucagon-producing cells effect of bile salts on the colon, ursodeoxycholic acid to reduce
found in the ileum. Enteroglucagon stimulates ornithine decarboxylase, cholestasis, and intermittent use of oral antibiotics to reduce bacterial
which in turn stimulates crypt cell proliferation. In animal models, overgrowth (see algorithm in Figure 71.1).
other factors (e.g., glutamine, epidermal growth factor, cholecystokinin, Surgical Options
and somatostatin) have also been shown to be involved in intestinal
adaptation, although there is little evidence so far that their clinical use The main aims of surgery for SBS are to correct mechanical obstruc-
increases adaptation in humans. tion in order to decrease bacterial overgrowth, and to maximise bowel
The colon can become a digestive organ in patients with SBS. length. More recently, intestinal transplant has become a reality in
Bacteria in the colon can ferment undigested starch and fibres into selected centres worldwide. Stomas should be closed as early as pos-
short chain fatty acids, which are the preferred fuel for colonocytes. sible so that all potentially functional bowel is used.
An intact colon will increase its energy absorption during the adaptive Tapering
phase postoperatively by increasing the fermentation of carbohydrates. Isolated dilated stagnant sections of bowel are a site for bacterial
The caloric requirement per kilogram also decreases with age, overgrowth. If symptoms of bacterial overgrowth are present, then
particularly after 1 year of age, which also contributes towards adapting dilated segments should be treated with tapering, especially in the
to a shorter bowel length. duodenum and jejunum. This procedure involves excision of the
Management antimesenteric border of the dilated portion of bowel. This enables
more effective peristalsis, thus reducing stasis and bacterial overgrowth.
The initial and primary consideration in the immediate period following Inversion placation has been used in an attempt to preserve mucosa but
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extensive bowel resection concerns fluid and electrolyte balance, even
tends to unravel despite technical modifications such as seromuscular
before calories. Gastric hypersecretion in the early period requires con-
stripping of the inverted segment.
trol with an H receptor antagonist or proton pump inhibitor. Patients
2 Bowel Lengthening
should be initially kept NPO (nothing by mouth) and have a nasogastric
Bowel lengthening relies on the presence of dilated bowel resulting
tube placed on free drainage, as well as a urinary catheter placed for
from intestinal adaptation and should therefore be reserved until 6
monitoring fluid balance. All patients will require intravenous fluids to
months to 1 year following initial bowel resection.
replace fluid losses.
The two main bowel-lengthening procedures are Bianchi’s
Sodium and potassium chloride are the most important ions to closely
longitudinal intestinal lengthening and tailoring (LILT) and serial
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monitor and replace. An infusion of normal saline (0.9%) with potassium
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transverse entroplasty (STEP) .
chloride should be used to replace millilitre for millilitre measured enteral
Bianchi’s LILT procedure (Figure 71.2) makes use of the bifurcation
(stoma and nasogastric) fluid losses. Additional amounts of sodium and
of the mesenteric vessels at the mesenteric border of the small bowel.
potassium may need to be given separately to avoid deficiency. Urine
The bowel is divided longitudinally between the mesenteric and
output should be monitored, and an adequate urine output maintained.
antimesenteric borders along its dual blood supply, dividing the bowel
Urinary sodium levels, where available can also be used to monitor
into two limbs, each with a blood supply. These two limbs are then
sodium loss. A urine sodium level >30 mmol/l should be maintained.
closed and anastomosed end to end, thus doubling that length of bowel.
Nutritional therapy should not be introduced until the patient is
In one series, 9 of 20 patients survived with this procedure, 7 of
haemodynamically stable and fluid management is relatively stable,
whom were able to wean off TPN. Factors associated with success were
which is likely to be a few days after bowel resection.
lack of liver failure and presence of at least 40 cm of intestine before
Nearly all patients with SBS will require parenteral nutrition to
the doubling procedure.
survive the period while the bowel adapts. Avoidance of TPN depends
on the anatomy of the remaining bowel; patients with an intact colon
are the most likely to be able to survive without TPN.
Oral feeds can be started at the same time as parenteral feed and
gradually increased as tolerated by the patient. Parenteral nutrition is
then decreased as enteral feeding is increased.
In infants, breast milk with oral sodium and vitamin supplements
can be used. C
The initial oral treatment in older children should be with oral
rehydration solution and a gradual introduction of carbohydrates. A
Children with SBS will require a diet high in calories from both fat
and carbohydrates to provide sufficient calories despite malabsorption.
They will also need supplements of potassium, sodium, magnesium,
calcium, fat-soluble vitamins (large doses of vitamins A, D, and E),
and zinc. Sodium is vital because it stimulates the bowel to absorb,
promoting adaptation. Vitamin B injections are specifically required
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with the loss of the distal ileum. B
Loperamide can be used to slow intestinal transit and decrease
diarrhoea. In those patients with a stoma, effluent from the proximal
bowel stoma can be introduced down the mucous fistula to promote
Figure 70.2: Bianchi’s LILT procedure: (A) A natural plane between the leaves
bowel growth and adaptation of the distal bowel before stoma closure. of the mesentery is found by dividing the bowel as shown (dotted line) and
As feed is introduced, those patients who will tolerate enteral using upwards and outwards traction on the divided bowel. The bowel and
feeding and those who will be dependent on parenteral nutrition will mesentery are divided into two along the length so each hemisegment of
become apparent. Bowel adaptation can take months or years, so bowel has a leaf of mesentery with blood supply. (B) The two hemisegments
survival of these patients will depend on funding for, and availability are then tubularised by using a continuous horizontal mattress 5/0 absorbable
suture. (C) The opposite ends of the two new bowel segments are apposed and
of, home parenteral nutrition.
anastomosed in an S-shape with the bowel overlying the mesentery.