Short bowel syndrome causes of it treatment

1. Small bowel fistula
&
Short bowel syndrome
MAMOON SALEH

2. Outlines:
Definition and types of small bowel fistulas.
 Causes of small bowel fistulas.
Clinical Presentation of small bowel fistulas.
Complication and treatment of small bowel fistulas.
Definition of short bowel syndrome.
Intestinal adaptation.
Treatment of short bowel syndrome.

3. Small bowel fistula

4. Definition :
Fistula is defined as an abnormal communication between two epithelialized
surfaces.
Types :
The communication occurs between two parts of the gastrointestinal tract or
adjacent organs in an internal fistula (enterovesical fistulas, enterovaginal fistulas,
and vascular enteric fistulas).
An external fistula (e.g., enterocutaneous fistula) involves the skin or another
external surface epithelium.
lleum is the most common site of ECF.

5. Enterocutaneous fistulas that drain less than 200 mL of fluid per day are known as
low-output fistulas, whereas those that drain more than 500 mL of fluid per day are
known as high-output fistulas.
Five mechanism of small intestinal fistulas have been identified:
1. Congenital (rare).
2. Trauma.
3. Infection.
4. Perforation/injury.
5. Inflammation.

6. Clinical Findings :
A. Symptoms and Signs.
B. Laboratory Findings.
C. Imaging Studies.

7. Clinical Presentation :
Iatrogenic enterocutaneous fistulas usually become clinically evident between the
fifth and tenth postoperative days.
Fever, leukocytosis, prolonged ileus, abdominal tenderness, and wound infection
are the initial signs.
The diagnosis becomes obvious when drainage of enteric material through the
abdominal wound or through existing drains occurs.
These fistulas are often associated with intra-abdominal abscesses.

8. Diagnosis :
CT scanning following the administration of enteral contrast is the most useful initial
test. Leakage of contrast material from the intestinal lumen can be observed.
If the anatomy of the fistula is not clear on CT scanning, an enteroclysis
examination can be obtained to demonstrate the fistula’s site of origin in the bowel.
A fistulogram, in which contrast is injected under pressure through a catheter
placed percutaneously into the fistula tract, may offer greater sensitivity in localizing
the fistula origin.

10. Complications :
Fluid and electrolyte losses, malnutrition, hemorrhage.
Sepsis contribute to multiple-organ failure and death unless effective therapy is
instituted promptly.
Hypokalemia is the most common electrolyte abnormality.

12. The overall objectives are to increase the probability of spontaneous closure.
Nutrition and time are the key components of this approach.
Most patients will require TPN; however, a trial of oral or enteral nutrition should be
attempted in patients with low-output fistulas originating from the distal intestine.
The somatostatin analogue octreotide is a useful adjunct, particularly in patients
with high-output fistulas.
Use of negative pressure wound therapy has increased in management of
enterocutaneous fistulas.

13. Most surgeons would pursue 2 to 3 months of conservative therapy before
considering surgical intervention.
This approach is based on evidence that 90% of fistulas that are going to close do
so within 5 weeks and that surgical intervention after this period is associated with
better outcomes and lower morbidity.
If the fistula fails to resolve during this period, surgery may be required, during
which the fistula tract, together with the segment of intestine from which it originates,
should be resected.

14. Short bowel syndrome

15. Definition :
Reflecting a state of significant malabsorption of both macronutrients and
micronutrients
Some have used a more anatomical definition with it being arbitrarily defined as the
presence of less than 200 cm of residual small bowel in adult patients.
In adults the most common etiologies of short bowel syndrome are acute
mesenteric ischemia, malignancy, and Crohn’s disease.
In pediatric patients, intestinal atresias, volvulus, and necrotizing enterocolitis.

16. Resection of less than 50% of the small intestine is generally well tolerated.
However, clinically significant malabsorption occurs when greater than 50% to 80%
of the small intestine has been resected.
However, this depends on the amount of bowel removed and the specific level of
resection, the presence or absence of the colon and the absorptive function of the
intestinal remnant.

17. Most common causes: Mesenteric infarction, Crohn’s disease, trauma
Most common cause in neonates: Necrotising enterocolitis*
Resection of terminal ileum: Malabsorption of bile salts and vitamin B12
Proximal small intestine resection is well tolerated than distal resection.
If ileocecal valve and terminal ileum is preserved patient can tolerate 70% bowel
loss.

18. INITIAL DETERMINANTS OF INTESTINAL FUNCTION:
Length of the intestinal resection (relative to age or body size)
Loss of the ileum and ileocecal valve
Loss of all or part of the colon
Continuity versus incontinuity of the intestines

19. INTESTINAL ADAPTATION :
The process following intestinal resection whereby the remaining bowel undergoes
macroscopic and microscopic changes that serve to increase its absorptive ability.
 Characterized by improved intestinal absorption, increased gut hormonal secretion,
development of hyperphagia, and changes in gut microbiota.
Adaptation is highly variable and usually occurs during the first two years following
intestinal resection.
changes include dilation and elongation of the remnant bowel, an increase in
intestinal wet weight, protein and DNA content, villus lengthening, expansion in
microvilli, and an increase in crypt depth and enterocyte number.

20. Treatment :
1. Medical management:
Treat the underlying cause.
Repletion of fluid and electrolytes lost in the severe diarrhea.
TPN, at least initially then Enteral nutrition should be gradually introduced, once
ileus has resolved.
High-dose histamine-2 receptor antagonists or proton pump inhibitors should be
administered to reduce gastric acid secretion.
Octreotide can be administered to reduce the volume of gastrointestinal secretions.
Promising regimens include GLP-2 and the combination of glutamine and growth
hormone with a modified, high-carbohydrate diet.

21. 2. Nontransplant Surgical Therapy:
The goal of these operations is to increase nutrient and fluid absorption by either
slowing intestinal transit or increasing intestinal length.
reversal of the small bowel, interposition of a segment of colon between segments
of small bowel, construction of small-intestinal valves, and electrical pacing of the
small intestine.

22. 3. Intestinal Transplantation:
Specific complications for which intestinal transplantation is indicated include :
(a) impending or overt liver failure,
(b) thrombosis of major central veins,
(c) frequent episodes of catheter related sepsis,
(d) frequent episodes of severe dehydration.