Enterocutaneous Fistula 

A fistula is an abnormal communication between 2 epithelialized surfaces, with an enterocutaneous fistula (ECF) being an abnormal communication between the small or large bowel and the skin. An ECF can arise from the duodenum, jejunum, ileum, colon, or rectum. (See the image below.)

Although fistulas arising from other regions of the gastrointestinal (GI) tract (eg, stomach, esophagus) may sometimes be included in the definition of ECF, the discussion in this article is limited to the conventional definition of ECF. A fistula-in-ano, although anatomically an ECF, conventionally is not referred to as such, because its presentation and management are different.

An ECF, which is classified as an external fistula (as opposed to an internal fistula, which is an abnormal communication between 2 hollow viscera), is a complication that is usually seen following surgery on the small or large bowel. ECFs are a common presentation in general surgical wards, and despite advances in the management of these lesions, they are still responsible for a significant mortality rate, ranging from 5-20%, due to associated sepsis, nutritional abnormalities, and electrolyte imbalances.

Understanding the pathophysiology of, as well as the risk factors for, ECFs should help to reduce their occurrence. Moreover, the well-established treatment guidelines for these lesions, along with some newer treatment options, should help clinicians to achieve a better outcome in patients with an ECF.

Output-based classification

The type of ECF, as based on the output of the enteric contents, also determines the patient's health status and how the patient may respond to therapy. ECFs are usually classified into 3 categories, as follows^[1] :

• Low-output fistula (< 200mL/day),
• Moderate-output fistula (200-500mL/day)
• High-output fistula (>500mL/day)

A high-output fistula increases the possibility of fluid and electrolyte imbalance and malnutrition.

Surgical versus conservative treatment

The conventional therapy for an ECF in the initial phase is always conservative. Immediate surgical therapy on presentation is contraindicated, because the majority of ECFs spontaneously close as a result of conservative therapy. Surgical intervention in the presence of sepsis and poor general condition would be hazardous for the patient.

However, patients with an ECF with adverse factors, such as a lateral duodenal fistula, ileal fistula, high-output fistula, or a fistula associated with a diseased bowel, may require early surgical intervention.

Treatment of enterocutaneous fistulas (ECFs) continues to be a difficult task. The problems associated with an intestinal wound breakdown were mentioned as early as 53 BC, by Celsus, who stated that “the large intestine can be sutured, not with any certain assurance, but because this doubtful hope is preferable to certain despair; for occasionally it heals up."

In the mid-19th century, John Hunter also described the difficulties in treating ECFs, insisting that "in such cases nothing is to be done but dressing the wound superficially, and when the contents of the wounded viscus become less, we may hope for a cure."

In a landmark article, Edmunds et al provided a comprehensive discussion of ECF. Of 157 patients in the study, 67 developed ECF following surgery. Important complications of ECF included fluid and electrolyte imbalance, malnutrition, and generalized peritonitis. Mortality was 62% in patients with gastric and duodenal fistulas, 54% in patients with small-bowel fistulas, and 16% with colonic fistulas.^[2]

Enterocutaneous fistulas (ECFs) can occur as a complication following any type of surgery on the GI tract. Indeed, more than 75% of all ECFs arise as a postoperative complication, while about 15-25% of them result from abdominal trauma or occur spontaneously in relation to cancer, irradiation, inflammatory bowel disease, or ischemic or infective conditions. The etiology of ECFs can thus be characterized as postoperative, traumatic, or spontaneous.

Postoperative causes

Postoperative causes of ECFs include the following:

• Disruption of anastomosis
• Inadvertent enterotomy - Especially occurs in patients with adhesions, when dissection can cause multiple serosal tears and an occasional full-thickness tear
• Inadvertent small bowel injury - Occurs during abdominal closure, especially after ventral hernia repair

Disruption of anastomosis can result from inadequate blood flow due to an improper vascular supply, especially when extensive mesenteric vessels have to be ligated. Tension on anastomotic lines following colonic resection, restoration of continuity without adequate mobilization, or a minimal leak or infection can lead to perianastomotic abscess formation, resulting in disruption, as seen in patients with anterior resection for rectal carcinoma. In addition, if anastomosis is performed in an unhealthy bowel (eg, diseased, ischemic), it can lead to disruption and cause an ECF.

Inadvertent picking up of the bowel during abdominal closure can result in small-bowel fistula; this especially can occur with the use of open inlay mesh or intraperitoneal onlay mesh repair by laparoscopic method, when the viscera comes in contact with the mesh, leading to adhesions and sometimes to disruption.

Gastroduodenal fistulas are seen most often following surgery for perforated peptic ulcer, especially in developing countries, where perforated peptic ulcer is more common. In patients with a perforated duodenal ulcer, when the perforation is large, extensive contamination is present. When the duration between the perforation and the surgery is long, there is a high possibility of a leak following surgery, leading to a lateral duodenal fistula. This problem is difficult to treat, and the mortality rate is high. Other causes of gastroduodenal leak include surgery for cancers of the stomach and the biliary tract.

A colocutaneous fistula can develop following colonic surgery, especially when the blood supply to a low colorectal/anal anastomosis is compromised or when there is tension at the anastomotic suture line. This type of fistula can also result from diseases of the colon, such as inflammatory bowel disease or malignancy leading to perforation, pericolic abscess formation, and ECF. Surgery for appendicitis, appendicular perforation at the base, or drainage of an appendicular abscess can also lead to a colocutaneous fistula. Radiation therapy is also another major cause of colonic fistula.^[1]

Traumatic causes

Traumatic ECF results from iatrogenic surgical trauma to the bowel that may or may not be recognized. Road traffic accidents with injury to the gut can also lead to an ECF.^[3]

Spontaneous causes

Spontaneous causes of ECF, seen in about 20-30% of cases, include the following:

• Malignancy
• Radiation enteritis with perforation
• Intra-abdominal sepsis
• Inflammatory bowel disease - Such as Crohn disease^[1]

Ulcerative colitis can also lead to spontaneous ECF, but most cases of ECF associated with this inflammatory bowel disease occur as a postoperative complication of restorative proctocolectomy.^[4]

A duodenal fistula can occur in association with a perforated duodenal ulcer, but again, it most often arises postoperatively, resulting from a leak.

ECF is a common condition in most general surgical wards. Mortality rates have decreased significantly since the late 1980s, from as high as 40-65% to as low as 5-20%, largely as a result of advances in intensive care, nutritional support, antimicrobial therapy, wound care, and operative techniques.^{[5, 6]} Even so, the mortality rate is still significantly high, in the range of 30-35%, in patients with high-output ECFs.

Once a patient develops an ECF, the morbidity associated with the surgical procedure or the primary disease increases, affecting the patient's quality of life, lengthening his/her hospital stay, and raising the overall treatment cost. Malnutrition, sepsis, and fluid electrolyte imbalance are the primary causes of mortality in patients with an enterocutaneous fistula (ECF).

If sepsis is not controlled, progressive deterioration occurs and patients succumb to septicemia. Other sepsis-related complications include intra-abdominal abscess, soft-tissue infection, and generalized peritonitis.^[7]

However, patients with an ECF with favorable factors for spontaneous closure have a good prognosis and less mortality.

Favorable factors for spontaneous closure

Spontaneous closure of an ECF is determined by certain anatomical factors. Fistulas that have a good chance of healing include the following:

• End fistulas - Such as those arising from leakage through a duodenal stump after Pólya gastrectomy
• Jejunal fistulas
• Colonic fistulas
• Continuity-maintained fistulas - Allow the patient to pass stool
• Small-defect fistulas
• Long-tract fistulas

In addition, a fistulous tract of more than 2cm has a higher possibility of spontaneous closure. Spontaneous closure is also possible if the bowel wall disruption is partial and other factors are favorable. If the disruption is complete, surgical intervention is necessary to restore intestinal continuity.

Unfavorable factors for spontaneous closure

When an ECF is associated with adverse factors, then spontaneous closure does not commonly occur, and surgical intervention, despite its associated risks, is frequently required. In these patients, the outcome is less likely to be good.^[8]

Factors preventing the spontaneous closure of an ECF can be remembered using the acronym FRIEND; they are as follows^[9] :

• F oreign body
• R adiation
• I nflammation/infection/inflammatory bowel disease
• E pithelialization of the fistula tract
• N eoplasm
• D istal obstruction - A distal obstruction prevents the spontaneous closure of an ECF, even in the presence of other favorable factors; if present, surgical intervention is needed to relieve the obstruction

In addition, lateral duodenal, ligament of Treitz, and ileal fistulas have less tendency to spontaneously close.^[7]

Excoriation

Skin excoriation, seen in the image below, is one of the complications that can lead to significant morbidity in patients with ECF. When the enteric contents are more fluid than solid, this becomes a difficult problem, as the skin excoriation makes it difficult to put a collecting bag or dressings over the fistula, and more leak leads to an increase in the excoriation.

Features suggestive of an enterocutaneous fistula (ECF) include postoperative abdominal pain, tenderness, distention, enteric contents from the drain site, and the main abdominal wound. Tachycardia and pyrexia may also be present, as may signs of localized or diffuse peritonitis, including guarding, rigidity, and rebound tenderness.

Sepsis, electrolyte imbalance, and malnutrition

Patients with ECF present with associated complications, such as sepsis, fluid and electrolyte abnormalities, and malnutrition.

The degree of sepsis depends on the state of the ECF. If the fistula forms a direct tract through which the bowel contents are draining onto the skin, then the sepsis may be minimal, whereas if the fistula forms an indirect tract through which the bowel contents are draining into an abscess cavity and then onto the skin, the degree of sepsis may be higher. In the presence of extensive peritoneal contamination or generalized peritonitis with ECF, the patient can be toxic due to severe sepsis.

Leakage of protein-rich enteric contents, intra-abdominal sepsis, or electrolyte imbalance–related paralytic ileus, as well as a general feeling of ill health, leads to reduced nutritional intake by these patients, resulting in malnutrition. Sepsis, malnutrition, and electrolyte imbalance are the predominant factors that lead to death in patients with ECF.^[10]

As previously mentioned, a high-output fistula increases the possibility of fluid and electrolyte imbalance and malnutrition.

The following lab studies are performed in the evaluation of an enterocutaneous fistula (ECF):

• Total leukocyte count - Important because sepsis can lead to leukocytosis
• Serum sodium, potassium, and chloride levels - Electrolyte abnormalities can result from fluid and electrolyte loss
• Complete blood count (CBC), total proteins, serum albumin, and globulin - Can demonstrate the presence of malnutrition-associated anemia/hypoalbuminemia
• Serum transferrin - Low levels (< 200mg/dL) are a predictor of poor healing
• Serum C-reactive protein - levels may be elevated

Fistulography

During fistulography (images from which are seen below), a water-soluble contrast is injected into the fistulous tract. Fistulography is conventionally performed 7-10 days after the presentation of an enterocutaneous fistula (ECF) and provides the following information:

• Length of the tract
• Extent of the bowel wall disruption
• Location of the fistula
• Presence of a distal obstructionFistulogram showing enterocutaneous fistula. Fistulogram showing a colocutaneous fistula following anastomotic leak after colostomy closure.

Water-soluble contrast enema

The following is the classification for different types of tracts that can be seen, using a water-soluble contrast enema (WCE), in patients with ECF with failure of low colorectal anastomosis^[11] :

• I – Simple, short blind ending, < 2cm
• II - Continuous linear, long single, >2cm
• III - Continuous complex, multiple linear

Tract positions are as follows:

• Anterior - Ventral, 10- to 2-o’clock position
• Posterior - Dorsal, 4- to 8-o’clock position
• Lateral - Right (2- to 4-o’clock position) or left (8- to 10-o’clock position)

Additional tract features seen with a WCE include the cavity (pooling of contrast within space) and/or a stricture (narrowing of anastomosis, with hold of contrast). The presence of a stricture and a large cavity on WCE predicts failure of healing.

CT scanning

Computed tomography (CT) scanning is useful for demonstrating intra-abdominal abscess cavities. Such cavities can occur if an ECF has an indirect tract when it first drains into an abscess cavity and then drains to the exterior cavity. If an ECF is associated with an intra-abdominal sepsis, then interloop abscesses may be present.

Markers

Oral administration of a nonabsorbable marker (eg, charcoal, Congo red) can help to confirm the presence of an enterocutaneous fistula (ECF).

Methylene blue diluted in saline can be administered through a nasogastric tube as a simple bedside test to confirm the presence of an ECF, especially in patients with a gastrocutaneous or lateral duodenal fistula. This test can also help to determine whether the leak is from a segment that is in the continuity of the GI tract, especially in the case of proximal fistulas. However, because methylene blue loses diagnostic efficacy as it becomes diluted with intestinal secretions, its role in identifying distal ECFs is limited.

Conservative treatment should usually be administered for a period ranging from a few weeks to a few months. The principles of nonsurgical therapy for ECFs include the following:

• Rehydration
• Administration of antibiotics
• Correction of anemia
• Electrolyte repletion
• Drainage of obvious abscess
• Nutritional support
• Control of fistula drainage
• Skin protection

With the above-mentioned supportive therapy, spontaneous closure occurs in almost 70% of patients. In a study of 186 patients, Reber et al found that 91% of small intestinal fistulas that closed spontaneously did so within 1 month after sepsis was cured. The remaining fistulas that closed spontaneously did so by the end of 3 months after sepsis cure, with the rest of the lesions requiring surgical closure.^[12]

The fistula tract is intubated with a drain, as seen in the image below. Volume depletion from a proximal, high-output fistula can be controlled with the use of a long-acting somatostatin analog, octreotide, which acts by inhibiting GI hormones.

The administration of octreotide reportedly diminishes fistula output, but whether it shortens the time required for fistula closure remains to be proven.^[13] Draus et al recommended a 3-day trial of octreotide, maintaining that if the fistula output is reduced during this time, then administration of the drug should be continued.^[14] (Octreotide use is associated with an increased incidence of cholelithiasis.^[7] )

Hyon et al reported on a vacuum-sealing method to reduce output, in which a semipermeable barrier was created over the fistula by vacuum packing a synthetic, hydrophobic polymer covered with a self-adherent surgical sheet. To set up the system, the investigators built a vacuum chamber equipped with precision instruments; the chamber supplied subatmospheric pressures of 350-450mm Hg. The pressure reduced the daily fistula output from 800mL to about 10mL, thus restoring bowel transit and physiology.^[15]

Draus et al reported that the use of a vacuum-assisted closure (VAC) system for wounds, which consisted of an evacuation tube embedded in a polyurethane foam dressing, helped to improve the condition of the wound, prevented skin excoriation, and promoted wound contracture and healing.^{[14, 16]}

Common fluid and electrolyte problems that must be corrected in patients with an enterocutaneous fistula (ECF) include the following:

• Dehydration
• Hyponatremia
• Hypokalemia
• Metabolic acidosis

The author uses parenteral nutrition more often in patients with a proximal small-bowel ECF, especially if it is in the proximal jejunum, or with a high-output fistula. In patients with a distal ECF, the author prefers to use enteral nutrition whenever possible.

Studies have shown that the provision of only 20% of calories fed enterally may protect the integrity of the mucosal barrier, as well as the immunologic and hormonal function of the gut.^[7] Hence, a combination of parenteral and enteral nutrition can be used. In high-output fistulas, the author uses this combination therapy.

In patients with a proximal fistula, if a nasojejunal tube can be introduced beyond the site of the fistula, then these patients can be supported with enteral nutrition, provided that there are at least 4-5 feet of small bowel distal to it and no distal obstruction. Chronic small-bowel ECFs may need additional supplementation with copper, folic acid, and vitamin B-12.^[7]

Total parenteral nutrition

Total parenteral nutrition (TPN) is usually indicated with suspected gastric, duodenal, or small-bowel fistula. When the fistula output is very high, discontinuation of oral intake is recommended, because oral intake stimulates further losses of fluids, electrolytes, and protein via the fistula. A decrease in fistula output frequently occurs with the initiation of TPN.

Water requirements for TPN are 1 mL/kcal/24h. Electrolyte requirements for TPN are as follows:

• Sodium (Na) - 80-100mEq/day
• Potassium (K) - 75-100mEq/day
• Magnesium (Mg) - 15-20mEq/day
• Calcium (Ca) - 15-20mEq/day

Calorie and protein requirements are as follows:

• Maintenance – 25-30kcal, 1.0-1.2g/kg/day
• Moderate stress – 30-40kcal, 1.3-1.4g/kg/day
• Severe stress – 40-45kcal, 1.5-2.0g/kg/day

Protein (g)/6.25 should equal nitrogen (g), while the nonprotein calorie-to-nitrogen ratio should be as follows:

• Maintenance - 200-300:1
• Moderate stress - 150:1
• Severe stress - Less than 100:1

A standard, general purpose formula for TPN consists of the following:

• 75 g glucose
• 20 g amino acids
• 30 g lipids per 1000 mL

The introduction of ethyl vinyl acetate bags has made the admixture of fat emulsion with dextrose and amino acids possible (3-in-1 concept).^[17] This leads to a more uniform administration of a balanced solution containing the 3 macronutrients plus micronutrients over a 24-hour period.

Enteral nutrition

Enteral nutrition is the mainstay of treatment for patients with ECFs. In fistulas of the distal ileum, colon, or duodenum, enteral nutrition should be considered and can be administered by various routes. Conventionally, when a gastroduodenal anastomosis or closure is needed in adverse conditions, a concomitant feeding jejunostomy is performed, so that access is available for enteral nutritional support in case of an anastomotic leak.

The other routes of administration can be via nasogastric/jejunal tubes or a gastrostomy. High rates of feeding should be avoided to prevent hyperosmolar diarrhea. Elemental diets, that is, nonresidue balanced diets with protein components reduced to their basic elements, are preferred. When a tube enterostomy is performed, proper fixation is necessary to prevent complications, such as dislodgement of the tube or antegrade migration in the GI tract.^[18]

Based on the following fistula characteristics, Irrgang et al developed a fistula assessment guide that has aided skin management related to enterocutaneous fistulas (ECFs)^[19] :

• Origin of fistula
• Nature of effluent
• Condition of skin
• Location of fistula opening

For a high-output fistula, a pouch system is preferable to a conventional skin dressing. For a low-output fistula, a skin barrier with dressing/pouch is advocated.

The degree of skin irritation present (from erythema to maceration to skin loss) guides the type of skin-protecting agents that should be applied and the type of pouch system that should be used. In addition, an important consideration is whether the opening is flush with the skin, retracted and deep, close to bony prominences, or in an open wound.

Pouches used for skin care

When the fistula output is high, it is desirable to use a pouch for collecting the enteric effluents. Ostomy pouches in 1- or 2-piece designs with either a drainable clip or a urostomy-type closure can be cut and fit to perifistular skin. If the area of the fistula is on an irregular body contour, such as close to bony prominences, then a 1-piece pouch is more suitable, since it can adhere better. A transparent pouch is preferred over an opaque pouch, for visualization of the fistula. A pouch with a skin-barrier backing is more durable than one with an adhesive backing.

Skin barriers

Powder, paste, wafers, spray, and creams are used as skin barriers for the protection of skin from the enteric effluents.

Pectin-based wafers that melt and seal with the skin provide a good barrier and offer protection for a variable period before the skin breaks down and ulcerates. In low-output fistulas, absorbent dressings can be put on top of the skin-barrier wafer to absorb any effluent overflow. The skin wafer protects the adjoining skin from erythema and maceration.

Pectin- or karaya-based powders and paste are used. Powders are preferred over a paste in wet, weepy, perifistular skin when severe skin maceration is present. A generous amount of powder should be used and continuously added for good results. In patients with weepy skin and a high-output fistula, management becomes difficult.

A spray provides a protective film and is helpful for pouching, but it might not be beneficial if used alone.

Zinc creams, as shown in the images below, are used to waterproof and protect the skin. Again, a generous amount with continuous replacement is necessary, because the cream is washed away with discharging enteric effluents.

Electrical nerve stimulation (ENS) increases blood flow in ischemic tissues and encourages healing. Berna et al reported the successful use of ENS in 2 patients with a low-output ECF. In the study, the direction and depth of the fistula tract were ultrasonographically determined. A sterile compress impregnated with saline solution was then introduced through the fistula. The positive electrode was positioned on the compress and the negative electrode was positioned over the fistula orifice.^[20]

The treatment was given once a day for 1 hour, with one patient requiring 10 treatment sessions to heal and the second patient requiring 20 sessions. ENS was well tolerated by both patients and no complications were noted. No recurrence of the fistula occurred during a 3-year follow-up period.

Patients with an enterocutaneous fistula (ECF) with adverse factors may require earlier surgical intervention. These adverse factors include a lateral duodenal or ligament of Treitz fistula, an ileal fistula, a high-output fistula, or a fistula associated with diseased bowel, distal obstruction, or eversion of mucosa (shown below).

Because the possibility of spontaneous closure is reduced in patients with adverse factors, surgical intervention should be undertaken after a 4- to 6-week trial of conservative therapy, if no signs of spontaneous closure exist. Surgical procedures in patients with adverse factors can include draining an abscess, creating stomas by exteriorizing the bowel, or creating controlled fistulas. When feasible, resection of the fistula with restoration of GI continuity is performed.

In patients with no associated adverse factors, the author usually waits for about 3-4 months before surgical therapy for an ECF is planned.

Surgical therapy^{[21, 22]} should be undertaken in patients with conventional fistulas without any adverse factors if the patient is stable, free from all sources of sepsis, and can withstand the resectional procedure needed for fistula closure.^[7] It is also important that it be technically feasible to perform the procedure without taking a very high risk for injury to the bowel or other important structures. Patients with an almost completely healed wound with a fistulous opening (shown below) have a good chance of responding to surgical therapy.

As previously mentioned, patients should be stable and free from sources of sepsis before surgical correction of an enterocutaneous fistula (ECF) is undertaken. In these patients, antibiotic prophylaxis and parenteral nutrition should be supplemented during the preoperative and the perioperative periods to achieve good results. Enteral feeding should be decreased to allow luminal antibiotic preparation. Antibiotic therapy should be administered after checking the culture sensitivity of earlier-grown organisms.^[7]

Incision

When performing surgery for an enterocutaneous fistula (ECF), the author's policy is to always enter the abdomen through a fresh incision, since there is a possibility of the gut being adherent to the site of the incision of the index operation. If the native incision is supraumbilical midline, then the author takes an infraumbilical midline route and then extends it to the operative site.

If it is mid-midline, then the author makes an incision in the midline superior or inferior to the native incision or a transverse incision to approach the abdomen. The author always enters the peritoneal cavity in a relatively virgin area to lessen the chance of an inadvertent enterotomy.

Excision and restoration of bowel continuity

Once an assessment is made in the peritoneal cavity, then the entire bowel from the ligament of Treitz to the rectum is made free of all adhesions. Once this is achieved, the fistulous site is dissected free from the surrounding structures and a complete excision is done. The author prefers to do restoration of bowel continuity using a 2-layered anastomosis, employing interrupted, nonabsorbable suture of healthy and well-vascularized bowel. The author uses it for small-bowel, as well as large-bowel, anastomosis.

An inner layer with continuous, absorbable suture and an outer layer with interrupted, nonabsorbable suture can also be used to restore bowel continuity. Other alternatives include the use of staplers, especially in low colorectal anastomosis.

Treatment of abscess or diseased bowel

If an abscess or diseased bowel segments are seen, then drainage of the abscess or resection of the diseased bowel is performed.^[6] If the patient is sick and cannot withstand a resectional procedure, then exteriorization of the bowel via ileostomy or colostomy is carried out.

Roux-en-Y drainages or a serosal patch can sometimes be used, especially for a lateral duodenal fistula following a leak after simple closure of a perforated duodenal ulcer.^[7] However, the results of these procedures are not very encouraging. Converting a lateral duodenal fistula into an end fistula with a tube duodenostomy is a good option but may not be possible in most patients.

If anastomosis is performed close to a duodenojejunal flexure, then adequate decompression by gastrostomy and feeding jejunostomy are carried out. The latter is also performed when proximal fistula repair is undertaken (eg, lateral duodenal fistula).

In the postoperative phase of surgical therapy for an enterocutaneous fistula (ECF), good nutritional status is essential, because healing of the tissue and anastomosis depends on it.

Antibiotic cover is needed if the operation is performed in the presence of sepsis. Any flare-up of sepsis increases the possibility of breakdown of the anastomosis and of the abdominal wall closure (leading to dehiscence). However, unnecessary use of antibiotics can lead to resistance and should therefore be avoided.

Fluid and electrolyte balance with appropriate correction is also important, especially in patients with adverse factors (eg, high-output fistula).

Patients who develop spontaneous fistula due to disease need appropriate therapy (eg, infliximab for Crohn disease or antituberculous therapy for tuberculosis) during follow-up to prevent disease recurrence or recurrence of the ECF.^[23] In patients with a malignancy-related ECF, appropriate chemotherapy and radiation, if required, are administered to control the primary disease.

Following healing of a conventional fistula by spontaneous closure, patients should be informed that, because healing occurs with secondary intention, there is a possibility of development of an incisional hernia as a long-term complication of ECF.

In a study of 10 patients, fibrin glue completely sealed the majority of low- and high-output enterocutaneous fistulas (ECFs). In the investigation, by Rabago et al, the glue was used in the treatment of 7 patients with low-output fistulas and 3 patients with high-output fistulas, whose EFCs had failed to close after conservative therapy. Once a fistula had been endoscopically located, 2-4mL of reconstituted fibrin glue (Tissucol 2.0 at 37°C) was injected through a catheter. The patients required a mean 2.5 treatment sessions (1-5 sessions), and the mean healing time was 16 days (5-40d). The investigators found that 87.5% of the low-output fistulas and 55% of the high-output fistulas sealed completely. No complications occurred.^[24]

Truong et al described the use of a Vicryl plug in combination with fibrin glue in the treatment of ECFs.^[25] After the site of an ECF or anastomotic leak was endoscopically sealed with the plug and glue, 7 of the study's 9 patients healed completely.

In another study, however, when fibrin glue was introduced directly into an ECF through the fistula opening in the skin, the results were not encouraging, with the fistula healing in only 1 out of 8 patients.^[14]

Good results with endoscopic therapy suggest that, when possible, this technique can be used when other conservative methods fail.

Lisle et al described the successful treatment of 3 cases of enterocutaneous fistula (ECF) with the embolization of Gelfoam at the enteric opening of the fistula.^[26] In this technique, the ECF was assessed by CT scan and fistulogram to rule out any intra-abdominal abscess, distal bowel obstruction, active bowel inflammation, or foreign body that would prevent the fistula from healing. A fistulogram also provided information about the fistulous tract and the site of communication with the bowel.

A 5 French introducer sheath was passed along a guide wire into the tract under fluoroscopy and then removed, after which, Gelfoam strips or pledgets soaked in contrast material were introduced into the tract through the sheath and pushed down to plug the enteric opening of the ECF. All of the patients healed completely, with no recurrence of ECF in a 2- to 3-year follow-up period.^[26]

De Weerd et al described the use of a sandwich-design myocutaneous flap cover to close a high-output ECF.^[27] In the initial phase of treatment, the authors used a VAC system for wound care to promote the development of granulation tissue around the fistulous opening. The fistula was then closed with serratus muscle from a composite free latissimus dorsi–serratus flap. The large abdominal wall defect was closed with the musculocutaneous latissimus dorsi flap taken from the composite flap. The placement of a VAC system between the serratus muscle and the latissimus dorsi muscle helped to fix the serratus to the fistula.

Successful direct repair of an ECF using a surrounding fasciocutaneous flap has also been reported.^[28]