Intestinal fistulas are abnormal connections between two epithelial surfaces that can be internal or external. The majority of enterocutaneous fistulas are iatrogenic complications resulting from intestinal surgery. Clinical signs include drainage of enteric contents from surgical wounds or drains. Treatment involves stabilization, investigation to define the fistula anatomy, and rehabilitation with nutrition to allow spontaneous closure in many cases. Surgery is needed for fistulas that do not close and involves resection of the fistula tract and affected intestine. Intestinal fistulas can be challenging to treat and are associated with significant morbidity and mortality risks.

1. Intestinal Fistulas
Yonas ademe
Jan 2017

2. Introduction
• A fistula is defined as an abnormal
communication between two epithelialized
surfaces
• 2 types
– Internal fistula: the communication occurs between
two parts of the GIT or adjacent organs
• e.g., enterocolonic fistula or colovesicular fistula
– External fistula: involves the skin or another external
surface epithelium
• e.g., enterocutaneous fistula or rectovaginal fistula

3. Cont.
• Types of enterocutaneous fistulas
– Low-output
• Enterocutaneous fistulas that drain less than 200 mL of
fluid per day
– High-output fistulas
• Enterocutaneous fistulas that drain more than 500 mL
of fluid per day

4. Cont.
• More than 80% of enterocutaneous fistulas
represent iatrogenic complications that occur
as the result of enterotomies or intestinal
anastomotic dehiscences
• Fistulas that arise spontaneously without
antecedent iatrogenic injury are usually
manifestations of progression of underlying
Crohn's disease or cancer

5. Clinical Presentation
• Iatrogenic enterocutaneous fistulas usually become
clinically evident between the 5th and 10th postop
days
• Fever, prolonged ileus, abdominal tenderness,
wound infection, and leukocytosis 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

6. Cont.
• Fistulas have the potential to close spontaneously
• Factors inhibiting spontaneous closure
– Fistula related
• High output fistulas
• Epithelialization of the fistula tract
– Systemic factors
• Malnutrition
• Sepsis
– Bowel related
• Inflammatory bowel disease
• Cancer
• Radiation
• Obstruction of the intestine distal to the origin of the fistula
• Foreign bodies

7. Complications
• Dehydration
• Electrolyte abnormalities
• Malnutrition
• Skin excoriation
• Reccurrent UTIs
(Enterovesicular fistulas)
The loss of enteric luminal
contents, particularly from
high-output fistulas
originating from the
proximal small intestine

8. Diagnosis
• CT scan (with enteral contrast) is the most useful initial
test
– Leakage of contrast material from the intestinal lumen can
be observed
– Intra-abdominal abscesses can also be seen and drained
percutaneously
• Small-bowel series or enteroclysis
– If the anatomy of the fistula is not clear on CT scanning
• Fistulography
– A contrast is injected under pressure through a catheter
placed percutaneously into the fistula tract
– It may offer greater sensitivity in localizing the fistula origin

9. Cont.

10. Treatment
• The treatment of enterocutaneous fistulas
should proceed through an orderly sequence
of steps

11. Cont.
• Step 1: Stabilization
– Fluid and electrolyte resuscitation
– Nutritional rehabilitation
• Usually through the parenteral route initially
– Control of epsis
• Antibiotics and drainage of abscesses
– Protection of skin from the fistula effluent
• Ostomy appliances or fistula drains

12. Cont.
• Step 2: Investigation
– The anatomy of the fistula is defined using the
studies

13. • Step 3: Rehabilitation
– Probability of spontaneous closure is maximized
– Nutrition and time are the key components of this
phase
• 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
• 2 to 3 months are allowed for spontaneous closure
– Fistulas that do not close during this period are unlikely to do so
– ?The somatostatin analogue octreotide

14. Cont.
• Surgery
– Procedure
• Resection of the fistula tract, together with the segment of
intestine from which it originates
• Simple closure of the opening in the intestine from which
the fistula originates is associated with high recurrence
rates
– Patients with intestinal fistulas typically have
extensive and dense intra-abdominal adhesions
• As a result, operations performed for nonhealing fistulas
can present formidable challenges

15. Prognosis
• Enterocutaneous fistulas are associated with a
10 to 15% mortality rate, mostly related to
sepsis or underlying disease
• Overall, 50% of intestinal fistulas close
spontaneously

16. End!