2ENTERIC FISTULASrepresent a second group of complex intraperitoneal infectious processes.Mortality remains high, between l0-30% in recent series.largely due to the frequent complications of sepsis and malnutrition.Electrolyte imbalances, as a third key factor leading to mortality
3CLASSIFICATION Classified by: the anatomy of the stnrctures involved the amount and composition of drainagethe etiology responsible for their formationIn addition to classification,these distinctions may provide important prognostic information about the physiologic impact of fistulas andthe likelihood that they will close without surgical resection,the principal decision confronting the responsible surgeon.
4ETIOLOGIC CLASSIFICATION Enterocutaneous fistulas result from several processes:(1) diseased bowel extending to surrounding structures(2) extraintestinal disease involving otherwise normal bowel(3) trauma to normal bowel including inadvertent or missed enterotomies(4) anastomotic disruption following surgery for a variety of conditionsFistulas between the alimentary tract and skin may be classified as postoperative or spontaneous.
5ETIOLOGIC CLASSIFICATION Approximately three-quarters of fistulas occur following:an operation,most commonly subsequent to procedures performed for malignancy, inflammatory bowel disease, or adhesions
6ETIOLOGIC CLASSIFICATION Patient factors that increase the likelihood of developing a postoperative fistula include:MalnutritionInfectionemergency operations with concomitant hypotension, anemia, hypothermia,and poor oxygen delivery
7ETIOLOGIC CLASSIFICATION If possible, these conditions should be corrected prior to operation,but in emergency situations, optimization of resuscitation and performance of a technically meticulous procedure including adequate mobilization, good quality bowel with good blood supply, and no tension will provide the best chance of a good outcome.
8ETIOLOGIC CLASSIFICATION Postoperative enterocutaneous fistulas result from:either disruption of the anastomosisinadvertent (and often unrecognized) bowel injury during the dissection or abdominal closureAttention to avoidance of tension or ischemia in the creation of anastomoses is paramount in minimizing postoperative enterocutaneous fistulas.The remaining 25 percent of fistulas do not occur following a surgical procedure.
9spontaneous fistulas spontaneous fistulas often develop in: patients with cancerFollowing radiation therapyFistulas occurring in the setting of malignancy or Irradiation are unlikely to close without operative intervention.Inflammatory conditions such as:inflammatory bowel diseasediverticular diseaseperforated ulcer diseaseIschemic bowel
10spontaneous fistulasOf these, fistulas in patients with inflammatory bowel disease are most common; these fistulas often close following a prolonged period ofparenteral nutrition, only to reopen when enteral nutrition resumes.An understanding of the etiology of an enterocutaneous fistula may provide information about the ultimate need for surgical intervention.
11ANATOMIC CLASSIFICATION Fistulas may communicate withthe skin (external fistulas)or other intraperitonealor intrathoracic organs (internal fistulas)
12ANATOMIC CLASSIFICATION Internal fistulas that bypass only short segments of bowel may not be symptomatic; however,internal fistulas of bowel that bypass significant length of bowel or that communicate with either the bladder or vagina typically cause symptoms and become clinically evident.However,internal fistulas of bowel that bypass significant length of bowel or that communicate with either the bladder or vagina typically cause symptoms and become clinically evident. The identification and management of internal fistulas is beyond the scope of this
13ANATOMIC CLASSIFICATION internal fistulas should be resected if :they are symptomaticcause physiologic or metabolic complications
14Small bowel fistulas.The majority of gastrointestinal cutaneous fistulas arise from the small intestine.Seventy to ninety percent of enterocutaneous fistulas occur in thepostoperative period.postoperative small bowel fistulas result from either disruption of anastomoses or injury to the bowel during dissection or closure of theabdomen.Operations for cancerin flammatory bowel disease, and adhesiolysis are the most common procedures antecedent to small bowel fistula formation.
15Small bowel fistulasDuring the course of a procedure, resection with end-to-endanastomosis is recommended for small bowel defects and injuries, especially when simple closure would be expected to reduce the luminal diameter.All sersosal injuries should be repaired with intermpted 3-0 silk sutures.Spontaneous small bowel fistulas arise from inflammatory bowel disease, cancer, peptic ulcer disease, or pancreatitis.Crohn's disease is the most common cause of spontaneous small bowel fistula.The transmural inflammation underlying Crohn's disease may lead to adhesion of the small bowel to the abdominal wall or other abdominal structures.
16Small bowel fistulasMicroperforation may then cause absces formation and erosion into adjacent structures or the skin.Roughly half of Crohn's fistulas are internal and half are external.crohn's fistulas tpyically follow one of two courses:The first type represents fistulas that present in the early postop_erative period following resection of a segment of diseased bowel.These fistulas arise in otherwise healthy bowel and follow a course similar to non-Crohn's fistulas with a significant likelihood of sponta_neous closure.The other group of Crohn's fistulas arises in diseased bowel and has a low rate of spontaneous closure.
17Small bowel fistulasAdditionally, should spontaneous closure occur, these fistulas often reopen upon resumption of enteral intake.Early operative closure of these fistulas should be considered.
18Colonic fistulasSpontaneous fistulas of the colon result from diverticulitis, malignancy, inflammatory bowel disease, appendicitis, and pancreatitis, while treatment of these conditions accounts for the majority of postoperative colocutaneous fistulas.Anastomotic breakdown or extension from inadequately resecteddisease bowel account for the majoriry of the postoperative fistulas.Additionally,with gastrocutaneous fistulas, an increased incidence of colocutaneous fistulas has been reported following percutaneousgastrostomy placement.
19Colonic fistulasAppendiceal fistulas may result from drainage of an appendiceal abscess or appendectomy in a patient with Crohn's disease.the fistula often originates from the terminal ileum, not the cecum.The inflamed ileum adheres to the abdominal wall closure and sub_sequently results in fistula formation.Erosion of a percutaneous drain for spontaneous right lower quadrant abscess is also an increasing cause of gastrointestinal cutaneous fistula in Crohn's disease.Radiation therapy contributes to both spontaneous and postoperative colocutaneous fistulas.
20Colonic fistulasTechniques to provide additional protection and blood supply toanastomoses performed under these conditions include coverage of anastomoses with omentum, filling of dead space with muscle flaps, or sigmoid exclusion.proximal diverting colostomy or ileostomy may allow sufficient anastomotic healing prior to sutureline challenge with luminal contents.Operation or reoperation in an irradiated field is subject to recurrence of colocutaneous fistulas, and these fistulas are unlikely to undergo spontaneous closure.
21Fistula tract characteristic addition to describing the organs involved in fistulas, anatomic characteristics of fistula tracts may also be helpful in determiningprognosis (Table 7-2).Due to anatomic considerations and the nature of effluent from different sites in the enteric tract, certain locations are more likely to undergo spontaneous closure.These favorable types include oropharyngeal, esophageal, duodenalstump, and jejunal fistulas.Unfavorable sites include the stomach, lateral duodenum, ligament of Treitz,and ileum.
23Fistula tract characteristic Anatomic factors suggesting low likelihood of spontaneous closure include fistulas associated with large abscesses, intestinal wall defects of greater than 1 cm, intestinal discontinuity, distal obstruction,diseased adjacent bowel, and fistulous tracts of less than 2 cm (Fig 7-5).In contrast, fistulas with intestinal wall defects less than 1 cm and longer tracts are more likely to undergo spontaneous closure.
26Physiological classification Enterocutaneous fistulas cause the loss of fluid, minerals,trace elements, and protein, as well as allow the release of irritating and caustic substances onto the skin and subcutaneous tissues.Accurate measurement of both the amount and nature of enteroCutan_eous effluent allows for accurate replacement and an understandingof the physiologic and metabolic challenges to the patient (Table 7-3).Fistulas may be divided into high-output (>500 mL per day), moderate-output ( mL/day), and low-output (<200 mL/day)groups.
28Physiological classification Classification of enterocutaneous fistulas by the amount of daily output provides information regarding mortality, and in recent series may predict spontaneous closure.the classic series of Edmunds and associates, patients with high-output fistulas had a mortality rate of 54%, compared to a l6% mortality rate in the low-output group.More recently,Lervy and colleagues reported a 50% mortality rate in patients with high-output fistulas, while those with low-output fistulas had a 26% mortality.
29Physiological classification In the largest series reported to date, Soeters and coworkers reported no association between fistula output and rate of spontaneous closure, while multivatiate analysis by Campos and associates suggested that patients with low-output fistulas were three times more likely to achieve closure without operative intervention.The reason for these different rates of closure is that high-output fistulas are likely to be of small-bowel origin,while low-output fistulas are likely to be of colonicorigin.Moderate-volume fistulas tend to be of either colonic or mixed small- and large-bowel origin (seeTable 7-2).
30PreventionProper preoperative patient preparation and meticulous surgical technique will lessen the risk of postoperative fistula formation.In the elective setting, operation may be delayed to allow for normali_ zaion of nutritional parameters, thus optimizing wound healing andimmune function.Several nutritional characteristics have been suggested to increase the risk of anastomotic breakdown:1. Weight loss of 10-15% of total body weight over 3-4 months2. Serum albumin less than 3 mg/dL3. Serum transferrin less than 220 mg/dL4. Anergy to recall antigens5. Inability to perform activities of daily living due to weakness or fatigue.
31PreventionMechanical and antibiotic bowel preparation reduce the amount of particulate fecal material as well as colonic bacterial counts. In practice, mechanical bowel preparation for elective colon operations combinedwith systemic antibiotics with activity against enteric organisms provides adequate prophylaxis.
32PreventionIn emergency operations, delays for optimization of nutritional status and bowel preparation are not possible.Instead, emphasis should be on adequate resuscitation and restoration of circulating volume, normalization of hemodynamics, provision of appropriate antibiotic therapy,and meticulous surgical techniquePerformance of anastomoses in a healthy, well-perfused bowel withouttension provides the best chance for healing, especially when one can easily see the performance of the anastomosis clearly.Careful hemostasis to avoid postoperative hematoma formation will decrease the risk of abscess
33Preventionwhile inadvertent enterotomies and serosal injuries should be identified and repaired. If possible, an omental flap should be used to separate the anastomosis from the abdominal incision.Secure abdominal wall closure using healthy tissue and care to avoid injury to the underlying bowel are important to prevent postoperativefistula formation.In the postoperative period, further resuscitation may be required to ensure hemodynamic stability and avoid inadequate tissue oxygenation.It is essential to avoid periods of transient postoperative hypotension related to the anesthesia.
34Diagnosis,Evaluation and Manegment Regardless of the etiology or specific nature of the fistula,the ultimate goals in treating patients with enterocutaneous fistula are the re-establishment of bowel continuity,the ability to achieve oral nutrition, and the closure of the fistula.Given the metabolic and septic physiology often present with entero_cutaneous fistulas, recognition of the development of an enterocu_ taneous fistula should prompt aggressive resuscitation and stabilization of the patient.
35Diagnosis,Evaluation and Manegment Drainage of obvious septic sources must be undertaken and nutritionalsupport commencedNutritional support should be delayed 24 hours for drainage, as hematogenous seeding of the catheter may result in catheter sepsis.If an abscess is pointing, one should do a fistulogram through the abscessb efore open drainage, using an angiocath to see where the water-soluble dye tracks to.
36Diagnosis,Evaluation and Manegment This information in combination with the patient's response to nonoperative measures determines the length of time before operative intervention is performed.If surgery is required, meticulous technique in combination with a well-prepared team approach will optimize the likelihood of a successful patient outcome.Operative closure of the fistula does not end the surgical team's obligation to the patient, as continued nutritional support and physical and emotional rehabilitation are often required to return the patient to his or her pre-illness state.As in any complicated illness, care of the patient with an enterocutan_ eous fistula can be divided into several phases (Table 7-4).
39Phase1:Recognition and Stabilization Identification and resuscitationthe patient presenting with a postoperative enterocutaneous fistula may do well initially for the first few days after operation.Within the first week, however, the patient may suffer delayed return of bowel function and fever.Erythema of the wound develops and opening the wound revealspurulent drainage that is soon followed by enteric contents.The diagnosis is now clear and management shifts from routine postoperative care to the management of a potentially critically ill patient.
40Phase1:Recognition and Stabilization The combined insults of the preoperative disease process,a bowel preparation, a week of minimal nutritional support, and a septic state often results in a profoundly volume-depleted patient.The first stage in management of the fistula patient, therefore, is therestoration of volume using crystalloid and colloid products as appropriate to restore oxygen-carrying capacity and plasma oncotic pressure.Several liters of crystalloid are usually required to replace fluid lostinto the bowel and bowel wall.
41Phase1:Recognition and Stabilization while maintenance of a specific target hematocrit is controversial, blood should be transfused to support oxygen-carrying capacity to a hematocrit of at least 30%.Similarly, albumin may aid in wound healing and intestinal functionoa and is involved in the transport of certain nutrients and medicationsAdministration of albumin to a serum level of 3.0 mg/dL supports these functions.
42Phase1:Recognition and Stabilization Control of SepsisThe leakage of enteric contents outside of the bowel lumen may lead to generalized peritonitis or abscess in addition to fistula formation.As the leading cause of mortality in modern series of enterocutaneousfistula, aggressive management of sepsis is essential in these patients.Frankly septic patients should be explored to drain abscesses.ursing these procedures, consideration should be given to performinga fistulogram by injecting water-soluble contrast into the abscess under fluoroscopic guidance.
43Phase1:Recognition and Stabilization Percutaneous drainage of collections in nonseptic patients should also be performed.Placement of central venous catheters for parenteral nutrition should be delayed for 24 hours following drainage of septic foci, as bacteremia following these procedures may seed catheters, leading to line sepsis.The use of antibiotics in patients with enterocutaneous fistulas should be reserved for specific indications.Most large series of patients with fistulas demonstrate that patients received seven to nine antibiotics during their treatment.in order to avoid selecting for resistant organisms, antibiotics should only be given for defined infections and for a set duration of therapy.
44Phase1:Recognition and Stabilization Control of fistula drinage and skin careConcorent with drainage of sepsis, a plan to control fistula drainage and provide local skin care will prevent continued irritation of the surrounding skin and abdominal wall structures.Very-low-output fistulas may appear to be adequately managed with dry dressings;however should the skin close over the fistula tract.In this experience, a sump constructed from a soft latex catheter (i.e., Robinson nephrostomy tube) may be placed in the wound (Fig 7-6).
46Phase1:Recognition and Stabilization This tube is soft at body temperature and will not erode into the bowel or abdominal wall structures.Accurate recording of fistula output is facilitated by this drainage system.More recendy, vacuum assisted closure (VAC) devices have been reported to both aid in the care of these complicated wounds and promote nonoperative closure( Fig 7-7).
48Phase1:Recognition and Stabilization while there are no large series or randomized trials of the use of these devices in the management of enterocutaneous fistula, VAC dressings provide another option for wound care in these patients.The disadvantage of VAC dressings is the amount of time necessary to change these dressings, often hours.However, these dressings need only bechanged every 5 or so days.
49Phase1:Recognition and Stabilization Reduction of fistula outputwhile fistula output does not correlate with the rate of spontaneous closure, reduction of fistula drainage may facilitate wound manage_ ment and decrease the time to closure.In the absence of obstruction, prolonged nasogastric drainage is notindicated and may even contribute to morbidity in the form of patient discomfort, impaired pulmonary toilet,alar necrosis, sinusitis or otitis media, and late esophageal stricture.Measures to decrease the volume of enteric secretions include admini_stration of histamine antagonists or proton pump inhibitors.
50Phase1:Recognition and Stabilization Reduction in acid secretion will also aid in the prevention of gastric and duodenal ulceration as well as decrease the stimulation of pancreatic secretion.Sucralfate, a mucosal protective agent, may also reduce gastric acidity while also providing a constipating action that may decrease fistulaoutput as well As inhibitors of the secretion of many gastrointestinal hormones inclu_ ding gastrin, cholecystokinin, secretin,insulin, glucagons, and vasoactive peptide.it has been hoped that somatostatin and octreotide may reduce time to closure and promote nonoperative closure of enterocutaneous fistulas.
51Phase1:Recognition and Stabilization Somatostatin and its analogue octreotide may be used to reduce gastrointestinal secretions, fistula output, and time to closure;however, data that demonstrate an effect on the rate of nonoperative closure of enterocutaneous fistulas are lacking.potential side effects of the use of these agents include difficult glucose homeostasis and cholelithiasis.Large prospective, randomized trials are needed to further clarify the role of somatostatin and octreotide in the management of enterocu_ taneous fistulas.Octreotide may accelerate closure of pancreatic fistulas.
52Phase1:Recognition and Stabilization however Infliximab, a monoclonal antibody to tumor necrosis factor-alpha, has been shown to be beneficial in inflammatory and fistulizing inflammatory bowel disease.Use of infliximab in patiens with fistulas following ileal pouch-anal anastomosis for ulcerative colitis resulted in clinical response in six of seven patients and fistula closure in five patients after three treatments.In a study of 100 patients with fistulizing Crohn's disease, infliximabinfusion resulted in complete response in 50 patiens,partial response in 22 patients, and no response in 28 patients.
53Phase1:Recognition and Stabilization In a randomized trial of patients with chronic fistulas (duration greater than 3 months), administration of infliximab resulted in a significantly increased rate of closure of all fistulas when compared to placebo.Adverse events in these trials were largely infectious complications, including abscess formation, pneumonia,varicella zoster, Candidn esophagitis, and upper respiratory tract infection.Evidence suggests a role of infliximab in treatment of fistulas compli_ cating inflammatory bowel disease; whether this agent will be of use in patiens without Crohn's disease or ulcerative colitis remains to be determined.
54Phase1:Recognition and Stabilization Nutritional supportProvision of nutritional support may be all that is necessary for spont_aneous healing of enterocutaneous fistulas.Alternatively, should operative intervention be required, normalization of nutritional parameters will provide the patient with the best chance for successful fistula resolution.Malnutrition,identified by Edmunds in 1960 as a major contributor to mortality in these patients, may be present in 55-90% of patients with enterocutaneous fistulas.
55Phase1:Recognition and Stabilization Patients with postoperative enterocutaneous fistulas are often mal_ nourished due to a combination of poor enteral intake, the hypercat_abolic septic state, and the loss of protein-rich enteral contents through the fistula.Proper nutrition may improve immune function, provide protein precursors for wound healing, and sup port the functions of the gastro_intestinal tract.
56Phase1:Recognition and Stabilization As a general guideline, we provide 25-32kilocalories per kilogram per day with a calorie:nitrogen ratio of 150:1 to 100:1 and at least 1.5 grams per kilogram per day of protein. These are general principles of nutritional management and ongoing reassessment of each patient'sclinical and laboratory values are required to optimize support for these complex patients.Parenteral nutrition has long been the corner_stone of support for patients with enterocutaneous fistu1as..
57Phase1:Recognition and Stabilization Transition to partial or total enteral nutrition has been advocated in recent reports to prevent atrophy of gastrointestinal mucosa as well as support the immunologic and hormonal functions of the gut and liver.Additionally, parenteral nutrition is expensive and requires dedicated nursing care to prevent undue morbidity and mortality from line insertion,catheter sepsis, and metabolic complications
58Phase1:Recognition and Stabilization Enteral feeding may occur per os, via feeding tubes placed nasogas_ trically or nasoenterically, or via the fistula itself (i.e., fistuloclysis).Enteral support typically requires 4 feet of small intestine and is contraindicated in the presence of distal obstruction.Drainage from the fistula may be expected to increase with thecommencement of enteral feeding; however, spontaneous closure may still occur, often preceded by a decrease in fistula output.
59Phase1:Recognition and Stabilization Eleven of twelve patients were able to discontinue parenteral support and nutritional status was maintained until surgery in nine patients (19_422days) and for at least 9 months in the two patients who did not undergo operative intervention.Of note, surgeons in this study also reported improved bowel caliber,thickness, and ability to hold sutures in patients who had received enteral nutrition
60Phase2:InvestigationOnce the patient has been stabilized with control of sepsis and comme-ncement of nutritional support, investigation into the course and character of the fistula should be undertaken.This typically occurs 7-10 days after the identification of the fistula and allows time for the fistula tract to mature to the point where catheterscan be placed in all orifices.Careful fistulography with water-soluble contrast provides informationnot obtainable through any other means.The senior surgeon responsible for the patient's care should be present with the most-senior available radiologist for the performance of the study.
61Phase2:InvestigationParticular attention should be paid to the length, course, and relation_ ships of the fistula tract, the absence or presence of bowel continuity or distal obstruction, the nature of the bowel adjacent to the fistula, and the absence or presence of an abscess cavity in communication withthe fistula (see Fig 7-5).
63Phase2:InvestigationThese details will help determine whether surgical intervention will be necessary as well as aid in the planning of such a procedure.The early films, without a lot of dye, give the most information.Computed tomography is most useful in the early management of patients with fistulas to identify abscesses and guide percutaneous interventions.Fistula tracts are not usually visible on axial CT imaging, althoughsagittal or reconstructed images may provide useful information.Barium contrast upper gastrointestinal studies and enemas rarely provide additional information.
64Phase3:DecisionIdeally, provision of a period of sepsis-free nutrition will result in closure of enterocutaneous fistulas within 4-6 weeks.Spontaneous closure of fistulas restores intestinal continuity and allows resumption of oral nutrition.Unfortunately, complex fistulas undergo spontaneous closure in only one-third of cases. Therefore, once resuscitation,wound care, and nutritional support are assured, a decision must be made regarding the likelihood of spontaneous closure of a specific fistula.Information obtained from imaging investigations provides anatomic details about the fistula, while the specifics of the clinical course of the patient, including weight gain, improvement in nutritional parameters,and decrease in fistula output provide prognostic details.
65Phase3:DecisionFistulograms demonstrating fistulas arising from diseased bowel, in proximity to large abscesses,in settings of disruption of intestinal continuity, in the presence of distal obstruction, and those with shorttracts (less than 2 cm) are unlikely to close without operative intervention.Similarly, fistulas originating in the stomach, ileum, or near the ligament of Tieitz have lower rates of spontaneous closure.In contrast,fistulas arising from biliary, pancreatic, or jejunalsources are more likely to resolve spontaneously (seeTable 7-2).Fistulas associated with inflammarory bowel disease often close with nonoperative management only to reopen upon resumption of enteral nutrition.
67Phase3:DecisionThese fistulas should be formally resected once closed to prevent recurrence.Fistulas in the setting of malignancy or irradiated bowel are particularlyresistant to closure and would suggest the need for earlier operative in_ tervention.The timing of operative intervention for fistulas that are unlikely to or fail to close is important.Early operation is indicated to control sepsis not amenable to percutaneous intervention.These early procedures are typically limited to drainage of abscess and resection of phlegmona with definitive resection of fistulas deferreduntil the patient can be nutritionally and physiologically optimized.
68Phase3:DecisionThe common practice of waiting at least 4-6 weeks for definitive operative management of enterocutaneous fistulas is based on several factors.First,90-95% of fistulas that will spontaneous close typically do so within 5 weeks of the original operatisn.Furthermore, operation during the first 10 days to 6 weeks from diagnosis of postoperative fistulas is made more difficult by the "obliterative peritonitis" described by Fazio and associates.In this series, reoperations within 10 days of or delayed at least 6 weeks from the original procedure resulted in mortality rates of l3%and 11%, respectively.
69Phase3:DecisionIn contrast, patients undergoing reoperations between l0 days and 6 weeks of the original laparotomy suffered a mortality rate of 26%.Additionally, delaying operative intervention allows for nutritional support and normalization of serum albumin and transferrin, while delay also allows resolution of local abdominal wound sepsis and preparation of the abdominal wall for secure closure.Optimally, if operation is required, 4 months should elapse from the last operative procedure because the adhesions will have matured and will be easier to deal with after that interval.
70Phase4:definitive manegment Just as the initial management and diagnosis of patients with gastrointestinal cutaneous fistulas is time- and labor intensive, the definitive operative reconstruction of these complicated patients requires the commitment of significant time and resources.The surgical team should expect to be in the operating room for up to 7or 8 hours.The patient should have achieved optimal nutritional parameters and be free of all signs of sepsis.
71Phase4:definitive manegment Through careful management of fistula drainage, a well-healed abdominal wall without inflammation should be present.Prophylactic antibiotics should be administered based on the patient's previous microbiological data, and tube feedings should be tapered inthe days preceding operation to allow mechanical and antibiotic preparation of the bowel.The operation should commence through a new incision distant from any potential sources of inflammation or infection.Often, a transverse incision offers the best opportunity to enter the abdomen in an area free of adhesions.
72Phase4:definitive manegment If the prior midline incision musr be used,entering the abdomen either above or below the limits of the previous incision reduces the risk of inadvertent entry into adherent bowel.Wound towels dipped in antibiotic solution or wound protectors should be used to prevent contamination of the abdominal wall tissues during the course o[the operation.Dissection to free the entire length of the bowel from the ligament of Theiz to the rectum is termed bowel refunctionalization.Refunctionalization identifies and allows resection of all areas of abscess and all sources of obstruction, thus ensuring the best possible chance of avoiding failure of the present operation.Dissection commences in the areas of least dense adhesions.
73Phase4:definitive manegment Use of antibiotic-soaked laparotomy pads on areas of dense adhesionsoften creates edema that aids in further dissection.Use of the scalpel and scissors to sharply dissect adhesions prevents inadvertent damage to the bowel, as does approaching adhesions from the side, rather than head-on.Careful attention to dissection and closure of all enterotomies in the manner of Heineke-Mikulicz and serosal tears with Lembert sutures of 5_0 Prolene provides the patient with the best possible outcome.Resection of the bowel involved in the fistula is preferred over bypass, Roux-en-Y drainage, or simple serosal patching, although these approaches may be necessary in extreme cases.
74Phase4:definitive manegment Bowel anastomosis should be performed using a two_layer, interrupted, end-to-end anastomosis with nonabsorbable sutures in healthy bowel.Avoiding tension and ensuring adequate blood supply are principles of sound surgical practice that must be followed in these difficult reoperative cases.Both throughout and following the steps of dissection,resection, and anastomosis, frequent irrigation of the abdominal cavity with antibiotic solution should be performed,and constant vigilance for inadvertent bowel injrry should be maintained.
75Phase4:definitive manegment For duodenal fistulas,however, if operation is required, a direct attack on the fistula is less wise.Instead a gastrojejunostomy, with or without vagotomy, with gastrostomy, jejunostomy, and drainage is most likely to give a successful result.Placement of a flap of omentum between the fresh anastomosis and the abdominal wall closure may prevent recurrence of fistulization.Use of Seprafilm may be an adjuvant therapy to aid in prevention of complications from future adhesions.
76Phase4:definitive manegment Consideration of Placement of a decompressive gastrostomy using a no20 whistle-tip catheter obviates the need for prolonged postoperative nasogastric tube placement in the event of prolonged ileus, which may be expected.Nasogastric tubes are uncomfortable and may interfere with ambulation and pulmonary toilet.Similarly,placement of a feeding jejunostomy may also aid in the postoperative care of patients undergoing procedures of this scale.Abdominal wall closure is the final operative step in the management of patients with enterocutaneous fistulas and is of utmost importance in preventing recurrence.If the abdominal wall has recovered from the previous inflammation and sepsis, a primary closure may be possible.
77Phase4:definitive manegment f a difficult closure is anticipated, a complex myocutaneous flap procedure may be required.The involvement of the plastic and recons_ tructive surgical service is advised under these circumstances and the use of a fresh team will maximize the likelihood of a good outcome for the patient.As the cumulative experience with complex laparoscopic procedures has increased, several groups have reported laparoscopic approaches to enteric and enterocutaneous fistulas.
78Phase 5:healingWhether closure of fistulas occurs spontaneously or through operative management, contimration of support is necessary to avoid recurrence.Nutritional support via tube feedings should be continued until the patient is consistently tolerating at least 1500 kilocalories per day orally.Healing of the surgical wound and anastomoses requires a positive nitrogen balance to avoid breakdown of newly formed proteins.Oral feeding typically commences 1 week postoperatively with a soft diet, rather than with the traditional progression from clear liquidsto full liquids.The patient's family and nutritional support staff will play an important role in providing foods that are appealing to the patient, as it is often difficult to persuade these patients to eat.
79Phase 5:healingZinc supplementation may improve patients' sense of taste and increase oral intake.Similarly, cycling tube feedings overnight may stimulate hunger and increase food intake during the day.Delayed complications continue to be a risk for fistula patients even after healing of their fistulas.Postoperative complications such as anastomotic stricture andadhesive small bowel obstruction, as well as short-bowelsyndrome due to multiple resections and recurrence of Fistuli_zation may all impede patient recovery.
80Phase 5:healingWhile reoperation in these patients remains a challenge, standardsurgical principles should be followed in decision making and performance of any further procedures.Physical and occupational therapists play a role throughout each patient's hospitalization, but their efforts become even more important during the healing phase as the focus shifts to reintroducing the patient to normal activities of daily living.
81Phase 5:healingInvolvement of case management staff early in the patient's course will identify obstacles to the patient's successful reintroduction to an active lifestyle,while use of psychiatric consultation-liaison services willidentify and address issues of depression and adaptive disorders.Finally, active involvement by the senior surgeon responsible for the patient's care to ensure a coherent treatrnent plan and adequate communication with the patient and family will help avoid confusion and fear while dealing with these challenging cases.One complication not widely reported is the inability of these patients to think clearly and have appropriate decision making.
82Phase 5:healingThis is particularly important for business owners and highly-placed executives.This is likely due to protein depletion in the brain. This complicationnormally takes months to resolve.The patient should be reassured that this complication will resolve spontaneously with good nutrition
83conclusionGastrointestinal cutaneous fistulas remain dreaded complications of cancer, inflammatory bowel disease,and general surgical operations.An understanding of the pathophysiology and risk factors for developmenr of these fistulas may minimize their creation as well asprovide a sound plan for their management.Early recognition and resuscitation of patients with fistulas combinedwith control of sepsis and provision of nutritional support may limit associated complications.Investigation into the anatomic and etiological characteristics of each fistula may provide information about the likelihood of spontaneous closure or suggest earlier operative management.
84conclusionCareful planning and technique during definitive surgical therapy and the involvement of a multidisciplinary team will provide the best possibility of resolurion of the fistula.Finally, postoperative maintenance of adequate nutrition and physicaland emotional support may allow restoration of the patient to a functional and productive role in society and ensures the durability of the repair.