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Intestinal failure in gastrointestinal fistula patients
ABDOMINAL SURGERY
Intestinal failure in gastrointestinal fistula patients
Home parenteral nutrition (HPN): is a method of delivering fluids and/or nutrients to a patient through a vein in the setting of a patient’s home. It is used where there is a chronic inability to adequately absorb enteral nutrition, in order to facilitate independence from the hospital setting.2
Faris Soliman
Classification of GIF
Rachel Hargest
There are several ways to classify fistulae, which may be based on anatomical, physiological or aetiological characteristics. There are many different anatomical types of GIF including those shown in Table 1. Enterocutaneous fistulae (ECF) are the most common type to cause intestinal failure and most of this chapter will discuss the management of ECF. Rarer GIF, such as those communicating with the biliary system, will not be specifically discussed but the basic principles of management apply. Type 1 fistulae e resulting from an underlying disease affecting the bowel wall. Type 2 fistulae e resulting from injury to a normal bowel wall. Alternatively, GIF can be defined as simple or complex: Simple fistulae drain via a short, simple track. Complex fistulae drain via long or multiple tracks and can include abscess cavities. The clinical management of GIF will vary depending on the physiological effects of the fistula. This depends on the volume (and to a certain extent the contents) of the fistula effluent, leading to a classification based on physiological effects: high output fistula e output>500 ml per 24 hours low output fistula e output<500 ml per 24 hours.
Abstract Intestinal failure due to gastrointestinal fistulae can be an extremely debilitating condition that significantly impairs quality of life. It can lead to serious life-threatening problems and may be fatal if left untreated. Patients may have a variety of underlying bowel diseases, or may have iatrogenic complications. Medical and psychological co-morbidities and complications present a further challenge in the successful management of these cases. In the acute stage, management of sepsis, fluid balance and acute surgical emergencies takes priority. Longer term maintenance of fluid and nutrient homeostasis, rehabilitation, psychosocial support and possible restorative intestinal surgery should all be addressed. A multidisciplinary approach is required to manage these patients appropriately. Services are usually concentrated in dedicated regional intestinal failure units comprising surgeons, gastroenterologists, radiologists, biochemists, nutritional support teams, stoma nurses as well as specialist wards equipped to manage these patients appropriately.
Keywords Fistula; intestinal failure; nutrition; short bowel syndrome
Definitions Intestinal failure (IF) is defined as ‘the reduction of gut function below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, to the point where supplementation is required to maintain health and/or growth’.1 It can be sub-classified into three types based upon duration of gut failure: type I: less than 28 days type II: greater than 28 days type III: generally irreversible.
Epidemiology The exact incidence and prevalence of patients with GIF and IF in UK hospitals is difficult to track and is probably under-reported. Many of these are in-patients who may receive TPN for a short time (<28 days) in order to recover from surgery or severe illness. It is estimated that there are between 1500 and 2000 inpatient cases per year of type II IF in England.3 Since 1995 the British Artificial Nutrition Survey (BANS) has recorded patients receiving HPN for type II or III IF. It is estimated that the prevalence of HPN cases in 2010 was 3.66 per million of the population with a period prevalence of 10 cases per million. There is no national or international record of the incidence and epidemiology of GIF. Many are unreported as low output postoperative GIF may close relatively quickly with conservative management, and even longer term low output GIF may require little ongoing medical attention. Fistulating conditions such as Crohn’s disease or radiotherapy predispose to GIF, particularly in the postoperative period.
Gastrointestinal fistulae (GIF): A fistula is defined as an abnormal communication between two epithelial lined surfaces. GIF is an abnormal track e at least one end of which is an epithelial surface within the gastrointestinal tract. Total parenteral nutrition (TPN): Is a method by which all the nutritional needs of a patient are provided directly into a vein, bypassing the enteric system.
Faris Soliman MRCS is a Specialist Training Registrar in General Surgery, Wales Deanery, UK. Conflicts of interest: none declared.
Causes of intestinal failure There are many causes of IF (listed in Table 2). Type I IF is of short duration and usually resolves after treating the underlying surgical or medical event. Type II and III IF are the more severe types of IF which will be considered in this article.
Rachel Hargest FRCS is a Senior Lecturer and Consultant Colorectal Surgeon at the University Hospital of Wales, Cardiff, UK. Conflicts of interest: none declared.
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ABDOMINAL SURGERY
Anatomical classification of gastrointestinal fistulae Fistula type
Abbreviation
From
To
Notes
Enterocutaneous
ECF
Small bowel
Skin
Gastrocutaneous Colocutaneous Enteroenteric Enterovesical Enterovaginal Colovesical
GCF CCF EEF EVF EVF CVF
Stomach Colon Small bowel Small bowel Small bowel Colon
Skin Skin Small bowel Bladder Vagina Bladder
Colovaginal
CVF
Colon
Vagina
Often associated with IF C Crohn’s C Trauma C Radiation C Surgery Variable output Distal enteral feeding possible Usually low output ‘Bypass’ effect UTIs common Vaginal discharge and UTIs common UTIs common Often diverticular UTIs common Often diverticular
UTI, urinary tract infection.
Table 1
A e ANATOMY e the location of the fistula must be established together with the length, condition and anatomy of the GI tract defined. P e PROCEDURE e definitive surgery to close the GIF, which fails to close spontaneously, should only be undertaken as a planned procedure when the above elements have been addressed. Initial assessment of the patient should address sepsis control and fluid balance. It is important to recognize that these are the key causes of morbidity and mortality in the early stages, and that rushing to address underlying anatomical abnormalities is usually counterproductive.
Causes of gastrointestinal fistula (GIF) GIF can be congenital or acquired. This article will consider the latter and causes are listed in Table 3.
Clinical features GIF may present in a variety of ways, depending upon the underlying cause and anatomical location of the fistula. ECF can present with drainage of intestinal contents either through the skin via a wound, drain site or an unexpected orifice. Figure 1 shows an ECF which developed in the midline wound after previous laparotomy. Enterovesical or colovesical fistulae can present with recurrent urinary tract infections or pneumato- or faecaluria. Gastrocolic fistulae may present with faeculant vomiting or faeculant halitosis. Enterovaginal or colovaginal fistulae can present with drainage of bowel contents per vaginally or recurrent urinary tract infections. The severity of symptoms and the magnitude of physiological derangement depend upon the anatomical site of the fistula. In general, fistulae that arise higher in the small bowel cause more fluid, electrolyte and nutritional disturbance. GIF draining into the urinary tract or vagina are more likely to cause septic complications, as do those GIF that fail to drain adequately or are associated with abscesses.
Sepsis Unresolved sepsis causes organ dysfunction and is a major cause of death in these patients. Sepsis may arise from the original abdominal condition, the chest, urinary tract, or bloodstream due to surgery or indwelling devices. Specimens for microbiological testing should include wound swabs, urine cultures, blood cultures (if pyrexial) and specimens from any drains, collections, discharges or indwelling devices where possible. Close liaison with a microbiologist is essential as many of these patients will have already had several and often prolonged courses of antibiotics and therefore atypical flora. Patients are also at risk of fungal colonization/infection due to the need for extended hospitalization and indwelling medical devices. Intra-abdominal sepsis should be sought with CT scanning in the first instance and, wherever possible, radiological drainage should be attempted to deal with any collections. Emergency surgery during the initial management stage should be reserved for the rare instances of major haemorrhage, removal of acutely ischaemic bowel or drainage of unresolved sepsis, which cannot be drained radiologically. In the emergency situation, divided
Initial assessment and management Traditionally, GIF management has been taught by the acronym SNAP: S e SEPSIS e must be eradicated by drainage of abscesses/collections and appropriate antimicrobial therapy. N e NUTRITION e the need for nutritional support must be assessed and where necessary fluid, electrolyte or calorie supplementation given.
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ABDOMINAL SURGERY
Causes of intestinal failure Type I C
Ileus e.g. GI surgery Other surgery Sepsis Head injury
Type II C
C
Type III
Abdominal catastrophe Mesenteric embolus Volvulus Major trauma Surgical complications Anastomotic leak Unrecognized intestinal injury Abdominal wall dehiscence Laparostomy
C
C C
Inflammatory bowel disease with complications where type II IF already present3 Intra-abdominal vascular catastrophe Volvulus
Table 2
bowel ends should be exteriorized and anastomoses avoided or at least defunctioned where possible.
Causes of gastrointestinal fistula Type 1 (Primary type) C C C C C C
C
Crohn’s/IBD Diverticular disease Malignant Severe pancreatitis Radiation enteritis Bowel obstruction with perforation Infections: TB Actinomycosis
Type 2 (Secondary type)
Nutrition While enteral nutrition is the preferred route, consideration must be given to the ability of the patient to absorb sufficient nutrients. Nutritional assessment is an important tool to assess this, using both subjective assessment via oral intake charts, and objective assessment via recording the patient’s weight and laboratory markers of nutrition status, as shown in Table 4. In order to survive on enteral nutrition, patients need sufficient small bowel absorptive capacity to avoid the need for parenteral fluids/calories. Generally 100e150 cm of small bowel is quoted as the threshold. However, there are several factors, which mean that no one length is appropriate for every patient: Patients with abnormal residual small intestine (e.g. Crohn’s or radiation enteritis) will require longer lengths of bowel than those whose residual small intestine is normal (e.g. trauma). Patients with most/all of the colon in situ will be able to absorb more fluid and electrolytes from the colon than those with an equivalent length of small bowel terminating in an ileostomy or ECF. Patients who retain their ileocaecal valve in continuity are usually able to manage with a relatively shorter small intestine due to the functional ‘hold up’ at the valve. In patients with a relatively high ECF or stoma and a long distal limb of ileum and colon, enteral tube feeding via the distal limb (fistuloclysis) may be successful in preventing the need for TPN. Parenteral nutrition (PN) must be used when IF is established and enteral intake is insufficient or inappropriate. Some patients may continue to eat but fluid restriction may be necessary if a high output GIF is present.
Risk factors: C Anastomotic leak C Enterotomy C Peritonitis C Trauma C Foreign body C Iatrogenic C Hepatic/renal insufficiency
Table 3
Considerations for TPN:4e7 1. Line issues: Choice of line Peripheral versus central: Peripheral lines provide short-term access. However, TPN causes severe vein irritation and therefore it is not practical to continuously replace peripheral access lines.
Figure 1 Enterocutaneous fistula in a midline wound after laparotomy.
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ABDOMINAL SURGERY
2. Metabolic issues: Appropriate systems must ensure that the correct volume of fluid and composition of nutrients are given to avoid complications such as cardiac volume overload or hepatic dysfunction from overfeeding. Administration of TPN by dedicated nutrition support teams reduces complications and improves cost effectiveness. The team commonly comprises a physician, nurse, dietician and pharmacist along with a GI surgeon, microbiologist, biochemist and psychologist. They aim to achieve a reduction in complications, inappropriate use of PN and improve planning of PN administration to reduce wastage. Typical nutrition requirements can be calculated in a variety of ways which recognize variations caused by metabolic stress and activity level. Generally, 20e30 Kcal/kg/day, with 1 g/kg/ day protein and 30e35 ml/kg/day fluids (excluding extra losses from fistulae, drains, etc.), is thought to be appropriate. Electrolytes and minerals including sodium, potassium, calcium, magnesium and phosphate should be addressed on an individual patient basis. Their losses should be monitored, with particular vigilance in patients with renal or liver impairment. Finally, micronutrients and vitamins also need to be considered for patients, particularly those on long term feeding.
Laboratory tests for monitoring nutrition support4 Monitoring test
Frequency
Sodium, potassium, urea, creatinine
C C C
Glucose
C C C
Magnesium phosphate
C C C
C
Liver function tests and international normalized ratio (INR) Calcium and albumin
C C C C C
CRP
C C
Zinc and copper
C C
Selenium
C C
Full blood count
C C C
Iron and ferritin
C C
Folate and B12
C C
Manganese 25-OH Vitamin D
C
Bone densitometry
C
C
C
Baseline Initially daily When stable: 1e2 times per week Baseline Initially: 1e2 per day When stable: 1 per week Baseline Initially daily Risk of re-feeding syndrome: 3 per week When stable: 1 per week Baseline Initially 2 per week When stable 1 per week Baseline Weekly Baseline When stable: 2e3 per week Baseline Depending on results: 1e2 per month Baseline (if risk of depletion) Further tests dependent on baseline Baseline Initially: 1e2 per week When stable: 1 per week Baseline Once every 3e6 months Baseline 1e2 per month Once every 3e6 months (HPN) Once every 6 months (long term support) Baseline taken at time of commencing HPN Once every 2 years
Other aspects: During the initial management phase while treating sepsis and nutrition, there are several other issues that must be addressed in order to prevent further complications and facilitate planning for definitive surgery. 1. Skin care Specialist stoma nursing care is required to manage ECF or defunctioning stomas with an appropriate appliance. ECF may cause severe skin inflammation (Figure 1) and necrosis if the alkaline fluid is allowed to stay in contact with the skin. Specialist products including pastes, skin barriers, seals, adhesive removers, absorbing agents, large volume collecting appliances and support belts all are used to prolong stoma bag life, prevent leakage and protect the skin. 2. High output stomas and ECF: ECF often act like high output stomas (HOS) due to their anatomical location. Recording accurate fluid balance is essential to management and awareness of the anatomy of the GIF and the length of proximal bowel is helpful. A pathological cause for high output should be excluded, for example partial bowel obstruction, intra-abdominal sepsis, enteritis (infective, radiation), medications (such as inappropriate use of prokinetics or recent changes to medication) or active inflammatory bowel disease. The relationship between oral intake and output can be demonstrated by fasting the patient and switching to parental nutrition and hydration. Gradual reintroduction of enteral fluids not only demonstrates high output due to oral intake, but also indicates how much reliance is needed on parenteral nutrition. It is a misconception that encouraging patients to drink large volumes of fluids will ensure hydration. Instead, this can actually stimulate huge losses of water and sodium. Fluid restriction may actually reduce losses. The type of oral fluid used is also important. Hypotonic or hypertonic solutions can cause excessive losses. In losses of 1.2 litres or more patients may be advised
Table 4
Central venous access provides a safer route for TPN administration for extended durations. Tunnelled versus non-tunnelled: Because of the distance between the skin puncture site and the entrance of the catheter into the vein, tunnelled lines carry less risk of infection and are therefore recommended in patients for long-term use (more than 30 days). Care of line Good nursing care is key to reducing septic line complications. It is recommended that dedicated lines for PN be used and nurses should be trained in aseptic technique. TPN lines should not be routinely used for blood sampling or administration of other drugs except in emergencies.
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ABDOMINAL SURGERY
to take isotonic solutions such as St Mark’s solution or World Health Organization Cholera solution. Drug therapy is important in HOS, particularly when oral restriction and isotonic solutions are not adequate. Anti-motility medication such as loperamide or codeine phosphate can serve to decrease sodium output by approximately one-third. Loperamide is preferred over opiates due to both the limited side effect profile and greater effect. When combined, however, the effect is further enhanced. It is important that drugs such as loperamide are administered as tablets, not capsules, which will not be absorbed in patients with IF. In these patients, doses of loperamide and codeine may be supranormal leading to problems when communicating with community doctors and pharmacists. Proton pump inhibitors should be given at high does for their anti-secretory effect. Bile acid sequestrants have been used in the treatment of high output ileostomies and could be of benefit in reduction of osmotically driven secretory diarrhoea from ECF. Somatostatin or its analogues such as octreotide may be useful in decreasing volume output. While their role is long established in pancreatic fistula, it has also been shown through a more recent systematic review that there is benefit and association with spontaneous and decreased time to closure of non-pancreatic fistulae.8 Finally, if the above methods fail it may be inevitable that some patients will need to maintain hydration by intravenous fluid and/or electrolytes and/or TPN. 3. Holistic care: Patients with GIF requiring TPN will often have had a significant period of hospitalization and be weak both physically and psychologically. Collaboration within the multidisciplinary team needs to address mobility and strength. Consideration also needs to be taken to identify psychological issues. Where possible, psychological and or psychiatric services should be made available. It is vital to ensure that the patient (and relatives) understand the serious and long-term nature of future definitive treatment of ECF so they have a realistic understanding before embarking on further surgery.
mortality if repeat surgery is undertaken in weeks 2e6. At this stage the abdomen is hostile due to the presence of early adhesions, and there is a high risk of iatrogenic damage. Therefore, provided that all sepsis is drained and there is no ischaemia or haemorrhage, surgery is often best deferred until reperitonealization has taken place and the patient’s general condition improved. As reperitonealization occurs, the abdomen becomes softer and it is common for an ECF to prolapse (Figure 2). This is a good sign that the adhesions in the abdomen will be more pliable and easier to dissect. It is common to encounter ECF patients who have been transferred between surgeons or units and have undergone multiple laparotomies over 2 to 4 weeks. The primary operation may have been for a relatively straight forward indication, e.g. appendicitis or small bowel resection, but complications have led to more technical difficulties with subsequent relook procedures. In general, it is unlikely that much can be achieved after two or three relook laparotomies. The first relook is obviously necessary to deal with anastomotic leak, ischaemia or haemorrhage and the operating surgeon may decide that a planned further procedure is necessary after 24 to 48 hours. At this second laparotomy the surgeon may deem it inappropriate to close the abdomen and plan a delayed closure. If progress is not been made by the third relook it is unlikely that anything strategic can be achieved at further laparotomies, assuming that an adequate assessment of the situation has been made at each operation. Unfortunately it is not unusual to receive patients who have undergone six to ten laparotomies during the episode, which led to the development of IF. These patients arrive in an extremely catabolic state with impairment of multiple organ systems. A considerable period of time is required to resuscitate and rehabilitate these patients such that it can easily be six months before they are ready for further surgery. Other factors affecting the decision to operate at a particular time include nutritional state, sepsis control and cardiopulmonary exercise (CPEX) testing to assess patient fitness prior to any major intervention. Once anatomy has been defined, the patient (and relatives) should be counselled regarding further definitive surgery. In some instances the risks of surgery may outweigh the inconvenience and morbidity of a relatively low output ECF, which is easy to manage with a stoma appliance and for which the patient only requires enteral nutrition. Patients with severe comorbidities may not be fit for further major laparotomy and may even prefer HPN. However, if the patient is, or can become, fit and has either a high output ECF and/or requires TPN then surgery will usually be recommended.
Definitive management Defining anatomy: If spontaneous closure of an ECF is going to occur, it is likely to do so within 6 weeks from commencement of conservative measures. After this point, spontaneous closure is unlikely, particularly in the presence of underlying disease. If definitive surgery is being considered, understanding the anatomy and relationship of the GIF to the gut and other abdominal organs is the first step in planning for reconstruction. It is also important to exclude distal obstruction and assess for underlying disease. Historically, plain X-ray contrast studies and fistulograms were the imaging methods of choice, and can still provide useful information when interpreted by an experienced clinician. CT or MR enterography are more commonly used today and are useful in establishing anatomical findings. Ultrasound has some use in repeat imaging and re-assessment of abscess cavities or other features identified by CT or MR imaging. Close collaboration with a specialist GI radiologist in this area is essential.
Procedure The steps that need to be addressed in a successful operative strategy include: safe access to the abdominal cavity resection of GIF and reconstitution of the GI tract abdominal closure the need for a defunctioning (temporary) stoma. Upon entering the abdomen the entire bowel from stomach to the rectum should be inspected and dissected free to isolate the GIF and ensure no distal obstruction is present. Measurement of the
Planning: Timing of definitive surgery is critical in determining outcome. In the authors’ experience, early intervention is ideal if a problem is identified in the first 10e14 days after initial surgery. However, there is a very high risk of further morbidity or
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be remembered that many patients may not have eaten properly for several months at this stage and the process may take several weeks, or even months. Even for those patients in whom IF is not permanent, the time spent recovering from the medical and surgical management of IF due to ECF is considerable. Patients often require many months in hospital with a period of rehabilitation in the community thereafter. These events can have a severe impact on patients both physically and mentally. Family and friends may also experience considerable strain, particularly if the patient has been transferred to a centre far from their home. Part of the role of the multidisciplinary team is to support the patient and their relatives through such a protracted and demanding process. Figure 2 Prolapsed enterocutaneous fistula.
Quality Assurance: Management of patients with IF is a complex multidisciplinary affair and there are many aspects of care which can be evaluated. Although individual patients present a unique combination of challenges, there are some common outcome measures which can be recorded: line infection rates unplanned returns to theatre GIF recurrence success in weaning from parenteral nutrition and intravenous fluid support mortality. BAPEN (British Association of Parenteral and Enteral Nutrition) and BIFA (British Intestinal Failure Alliance) have published a position statement on the quality of IF services and most UK units audit their outcomes against these standards.6
small bowel is important both before and after the GIF is excised to plan aftercare and will be useful in the event of further surgery. It is useful to document the length and condition of the small bowel plus the relative positions of any repairs, anastomoses or stomas as a structured operation note. All damaged bowel should be resected or repaired. Once the GIF and any non-viable bowel has been excised, reconstitution by one or more anastomoses should be performed, usually avoiding stapled anastomoses. Should multiple anastomoses be required, consideration must be given as to whether to defunction the patient while healing occurs. If so, a loop stoma should be fashioned to allow for a downstream contrast study prior to stoma closure. Reconstructive operations are complex in nature and long in duration. Decision making throughout the procedure will depend upon individual circumstances. Excessive haemorrhage, unsuspected sepsis, a frozen pelvis or abdomen and suspicion of malignancy are all factors which may mandate a change of plan. Basic surgical principles should be followed e stop haemorrhage, relieve obstruction and drain pus. Further iatrogenic damage carries a very poor prognosis. A high defunctioning stoma and a further period on TPN may be the least worst option for some patients. Finally, abdominal closure can create a challenge in itself and a variety of options exist, with the aim of ensuring appropriate cover of the bowel to prevent GIF recurrence, reconstruct the abdominal wall and prevent compartment syndrome. Component separation techniques can be valuable. When using mesh, it is important to select a mesh material that is going to reduce the chance of recurrence of GIF and that morbidity does not significantly increase if infection occurs. Therefore, Vicryl Ò or certain biological meshes are preferred over non-absorbable synthetic meshes.
Home TPN: For patients with type III IF, or those with type II who are awaiting surgery for a HOS or ECF, or reversal of a high defunctioning stoma, TPN may be administered at home. The nutrition support team will train appropriate patients in the practice of aseptic technique in order to connect and disconnect TPN infusions. Many patients (or a family member) can manage this independently at home. For those unable to do so, a community TPN nurse can be provided who will attend daily (if necessary) to set up and take down TPN. Blood tests should be performed (as per Table 4) in cooperation with the general practitioner or district nursing service. Home TPN patients are educated as to signs of sepsis, line complications or metabolic disturbances. They are also provided with the contact details of a TPN nurse during office hours, and the number of the gastroenterology or surgical ward in case of out of hours emergencies. Patients can be maintained on long-term TPN if necessary, but vigilance is required in order to reduce the risks of long-term thrombotic or infective line issues or worsening liver function. The mortality rate for IF patients receiving HPN should be less than 5% at 5 years. However, longer term there is a significant attrition rate due to acute sepsis, or gradually worsening liver dysfunction. Small bowel or combined liver and small bowel transplantation may be offered to some HPN patients. There is controversy as to whether patients requiring lifelong PN should be referred early (when their liver function is normal) to a small bowel transplant (SBT) unit, or whether combined transplantation should be reserved for those in whom the liver is beginning to fail. Because survival and quality of life on HPN are now so good, patients may be unwilling to embark on a risky
Recovery: Early postoperative care should take place in a critical care unit or a surgical ward with appropriately trained nurses familiar with the care of such complex cases. Strict attention to fluid balance, nutritional support, thromboembolic prophylaxis, pain relief and sepsis is essential. Early mobilization and physiotherapy is mandatory, and resumption of oral feeding is encouraged, even if the patient requires TPN because of a high defunctioning stoma. In those with sufficient intestinal length, a gradual approach is used to wean from TPN and resume full enteral intake. It should
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procedure which still has relatively high mortality rates and significant impact on quality of life postoperatively. Most IF units liaise closely with the supraregional small bowel transplant units so that appropriate patients can be discussed and referred for consultation. While SBT may be life saving in some cases, it is a major and risky procedure which should only be undertaken in specialized units after detailed assessment and counselling of patients with IF.
REFERENCES 1 Pironi L, Arends J, Baxter J, et al. ESPEN endorsed recommendations definition and classification of intestinal failure in adults. Clin Nutr 2015; 34: 171e80. 2 Jones B. Home parenteral nutrition in the United Kingdom; a position paper. The British association of Parenteral and Enteral Nutrition (BAPEN), 2003. 3 Agwunobi AO, Carlson GL, Anderson ID, Irving MH, Scott NA. Mechanisms of intestinal failure in Crohn’s disease. Dis Colon Rectum 2001; 44: 1834e7. 4 NHS commissioning, Specialised Services. 2013/14 NHS standard contract for Intestinal Failure (Adult), NHS England. A08/S/a. https://www.england.nhs.uk/wp-content/uploads/2013/06/a08intestinal-failure-adult.pdf (Accessed August 2017). 5 NICE nutrition support in adults: oral nutrition support, enteral tube feeding and parenteral nutrition. Feb 2006 (last updated August 2017). NICE clinical guideline 32, guidance.nice.org.uk/cg32. 6 http://www.bapen.org.uk/nutrition-support/parenteral-nutrition/ position-statement-from-bifa-committee. 7 Nightingale J, Woodward JM. Guidelines for management of patients with short bowel. On behalf of the Small Bowel and Nutrition Committee of the British Society of Gastroenterology. Gut BMJ Aug 2006; 4: 1e12. 8 Stevens P, Foulkes RE, Hartford-Benyon JS, Delicata RJ. Systematic review and metaanalysis of the role of somatostatin and its analogues in the treatment of enterocutaneous fistula. Eur J Gasteroenterol Hepatol 2011 October; 23: 912e22.
Summary IF is a very serious condition which is commonly due to GIF. Patients require the services of a multidisciplinary nutrition support team in order to optimize all aspects of their care. At presentation, many patients are acutely unwell with life-threatening septic and metabolic complications, which should be addressed urgently. Definition of anatomical features should be part of the planning for restorative surgery. Major restorative surgery should be undertaken when the patient is stable, and consideration should be given to the use of a high defunctioning stoma to cover any anastomoses. IF patients require significant attention to detail medically, and psychological support from the MDT in order to get through a prolonged episode of ill health. A
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Intestinal failure in gastrointestinal fistula patients
Home parenteral nutrition (HPN): is a method of delivering fluids and/or nutrients to a patient through a vein in the setting of a patient’s home. It is used where there is a chronic inability to adequately absorb enteral nutrition, in order to facilitate independence from the hospital setting.2
Faris Soliman
Classification of GIF
Rachel Hargest
There are several ways to classify fistulae, which may be based on anatomical, physiological or aetiological characteristics. There are many different anatomical types of GIF including those shown in Table 1. Enterocutaneous fistulae (ECF) are the most common type to cause intestinal failure and most of this chapter will discuss the management of ECF. Rarer GIF, such as those communicating with the biliary system, will not be specifically discussed but the basic principles of management apply. Type 1 fistulae e resulting from an underlying disease affecting the bowel wall. Type 2 fistulae e resulting from injury to a normal bowel wall. Alternatively, GIF can be defined as simple or complex: Simple fistulae drain via a short, simple track. Complex fistulae drain via long or multiple tracks and can include abscess cavities. The clinical management of GIF will vary depending on the physiological effects of the fistula. This depends on the volume (and to a certain extent the contents) of the fistula effluent, leading to a classification based on physiological effects: high output fistula e output>500 ml per 24 hours low output fistula e output<500 ml per 24 hours.
Abstract Intestinal failure due to gastrointestinal fistulae can be an extremely debilitating condition that significantly impairs quality of life. It can lead to serious life-threatening problems and may be fatal if left untreated. Patients may have a variety of underlying bowel diseases, or may have iatrogenic complications. Medical and psychological co-morbidities and complications present a further challenge in the successful management of these cases. In the acute stage, management of sepsis, fluid balance and acute surgical emergencies takes priority. Longer term maintenance of fluid and nutrient homeostasis, rehabilitation, psychosocial support and possible restorative intestinal surgery should all be addressed. A multidisciplinary approach is required to manage these patients appropriately. Services are usually concentrated in dedicated regional intestinal failure units comprising surgeons, gastroenterologists, radiologists, biochemists, nutritional support teams, stoma nurses as well as specialist wards equipped to manage these patients appropriately.
Keywords Fistula; intestinal failure; nutrition; short bowel syndrome
Definitions Intestinal failure (IF) is defined as ‘the reduction of gut function below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, to the point where supplementation is required to maintain health and/or growth’.1 It can be sub-classified into three types based upon duration of gut failure: type I: less than 28 days type II: greater than 28 days type III: generally irreversible.
Epidemiology The exact incidence and prevalence of patients with GIF and IF in UK hospitals is difficult to track and is probably under-reported. Many of these are in-patients who may receive TPN for a short time (<28 days) in order to recover from surgery or severe illness. It is estimated that there are between 1500 and 2000 inpatient cases per year of type II IF in England.3 Since 1995 the British Artificial Nutrition Survey (BANS) has recorded patients receiving HPN for type II or III IF. It is estimated that the prevalence of HPN cases in 2010 was 3.66 per million of the population with a period prevalence of 10 cases per million. There is no national or international record of the incidence and epidemiology of GIF. Many are unreported as low output postoperative GIF may close relatively quickly with conservative management, and even longer term low output GIF may require little ongoing medical attention. Fistulating conditions such as Crohn’s disease or radiotherapy predispose to GIF, particularly in the postoperative period.
Gastrointestinal fistulae (GIF): A fistula is defined as an abnormal communication between two epithelial lined surfaces. GIF is an abnormal track e at least one end of which is an epithelial surface within the gastrointestinal tract. Total parenteral nutrition (TPN): Is a method by which all the nutritional needs of a patient are provided directly into a vein, bypassing the enteric system.
Faris Soliman MRCS is a Specialist Training Registrar in General Surgery, Wales Deanery, UK. Conflicts of interest: none declared.
Causes of intestinal failure There are many causes of IF (listed in Table 2). Type I IF is of short duration and usually resolves after treating the underlying surgical or medical event. Type II and III IF are the more severe types of IF which will be considered in this article.
Rachel Hargest FRCS is a Senior Lecturer and Consultant Colorectal Surgeon at the University Hospital of Wales, Cardiff, UK. Conflicts of interest: none declared.
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Anatomical classification of gastrointestinal fistulae Fistula type
Abbreviation
From
To
Notes
Enterocutaneous
ECF
Small bowel
Skin
Gastrocutaneous Colocutaneous Enteroenteric Enterovesical Enterovaginal Colovesical
GCF CCF EEF EVF EVF CVF
Stomach Colon Small bowel Small bowel Small bowel Colon
Skin Skin Small bowel Bladder Vagina Bladder
Colovaginal
CVF
Colon
Vagina
Often associated with IF C Crohn’s C Trauma C Radiation C Surgery Variable output Distal enteral feeding possible Usually low output ‘Bypass’ effect UTIs common Vaginal discharge and UTIs common UTIs common Often diverticular UTIs common Often diverticular
UTI, urinary tract infection.
Table 1
A e ANATOMY e the location of the fistula must be established together with the length, condition and anatomy of the GI tract defined. P e PROCEDURE e definitive surgery to close the GIF, which fails to close spontaneously, should only be undertaken as a planned procedure when the above elements have been addressed. Initial assessment of the patient should address sepsis control and fluid balance. It is important to recognize that these are the key causes of morbidity and mortality in the early stages, and that rushing to address underlying anatomical abnormalities is usually counterproductive.
Causes of gastrointestinal fistula (GIF) GIF can be congenital or acquired. This article will consider the latter and causes are listed in Table 3.
Clinical features GIF may present in a variety of ways, depending upon the underlying cause and anatomical location of the fistula. ECF can present with drainage of intestinal contents either through the skin via a wound, drain site or an unexpected orifice. Figure 1 shows an ECF which developed in the midline wound after previous laparotomy. Enterovesical or colovesical fistulae can present with recurrent urinary tract infections or pneumato- or faecaluria. Gastrocolic fistulae may present with faeculant vomiting or faeculant halitosis. Enterovaginal or colovaginal fistulae can present with drainage of bowel contents per vaginally or recurrent urinary tract infections. The severity of symptoms and the magnitude of physiological derangement depend upon the anatomical site of the fistula. In general, fistulae that arise higher in the small bowel cause more fluid, electrolyte and nutritional disturbance. GIF draining into the urinary tract or vagina are more likely to cause septic complications, as do those GIF that fail to drain adequately or are associated with abscesses.
Sepsis Unresolved sepsis causes organ dysfunction and is a major cause of death in these patients. Sepsis may arise from the original abdominal condition, the chest, urinary tract, or bloodstream due to surgery or indwelling devices. Specimens for microbiological testing should include wound swabs, urine cultures, blood cultures (if pyrexial) and specimens from any drains, collections, discharges or indwelling devices where possible. Close liaison with a microbiologist is essential as many of these patients will have already had several and often prolonged courses of antibiotics and therefore atypical flora. Patients are also at risk of fungal colonization/infection due to the need for extended hospitalization and indwelling medical devices. Intra-abdominal sepsis should be sought with CT scanning in the first instance and, wherever possible, radiological drainage should be attempted to deal with any collections. Emergency surgery during the initial management stage should be reserved for the rare instances of major haemorrhage, removal of acutely ischaemic bowel or drainage of unresolved sepsis, which cannot be drained radiologically. In the emergency situation, divided
Initial assessment and management Traditionally, GIF management has been taught by the acronym SNAP: S e SEPSIS e must be eradicated by drainage of abscesses/collections and appropriate antimicrobial therapy. N e NUTRITION e the need for nutritional support must be assessed and where necessary fluid, electrolyte or calorie supplementation given.
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Causes of intestinal failure Type I C
Ileus e.g. GI surgery Other surgery Sepsis Head injury
Type II C
C
Type III
Abdominal catastrophe Mesenteric embolus Volvulus Major trauma Surgical complications Anastomotic leak Unrecognized intestinal injury Abdominal wall dehiscence Laparostomy
C
C C
Inflammatory bowel disease with complications where type II IF already present3 Intra-abdominal vascular catastrophe Volvulus
Table 2
bowel ends should be exteriorized and anastomoses avoided or at least defunctioned where possible.
Causes of gastrointestinal fistula Type 1 (Primary type) C C C C C C
C
Crohn’s/IBD Diverticular disease Malignant Severe pancreatitis Radiation enteritis Bowel obstruction with perforation Infections: TB Actinomycosis
Type 2 (Secondary type)
Nutrition While enteral nutrition is the preferred route, consideration must be given to the ability of the patient to absorb sufficient nutrients. Nutritional assessment is an important tool to assess this, using both subjective assessment via oral intake charts, and objective assessment via recording the patient’s weight and laboratory markers of nutrition status, as shown in Table 4. In order to survive on enteral nutrition, patients need sufficient small bowel absorptive capacity to avoid the need for parenteral fluids/calories. Generally 100e150 cm of small bowel is quoted as the threshold. However, there are several factors, which mean that no one length is appropriate for every patient: Patients with abnormal residual small intestine (e.g. Crohn’s or radiation enteritis) will require longer lengths of bowel than those whose residual small intestine is normal (e.g. trauma). Patients with most/all of the colon in situ will be able to absorb more fluid and electrolytes from the colon than those with an equivalent length of small bowel terminating in an ileostomy or ECF. Patients who retain their ileocaecal valve in continuity are usually able to manage with a relatively shorter small intestine due to the functional ‘hold up’ at the valve. In patients with a relatively high ECF or stoma and a long distal limb of ileum and colon, enteral tube feeding via the distal limb (fistuloclysis) may be successful in preventing the need for TPN. Parenteral nutrition (PN) must be used when IF is established and enteral intake is insufficient or inappropriate. Some patients may continue to eat but fluid restriction may be necessary if a high output GIF is present.
Risk factors: C Anastomotic leak C Enterotomy C Peritonitis C Trauma C Foreign body C Iatrogenic C Hepatic/renal insufficiency
Table 3
Considerations for TPN:4e7 1. Line issues: Choice of line Peripheral versus central: Peripheral lines provide short-term access. However, TPN causes severe vein irritation and therefore it is not practical to continuously replace peripheral access lines.
Figure 1 Enterocutaneous fistula in a midline wound after laparotomy.
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2. Metabolic issues: Appropriate systems must ensure that the correct volume of fluid and composition of nutrients are given to avoid complications such as cardiac volume overload or hepatic dysfunction from overfeeding. Administration of TPN by dedicated nutrition support teams reduces complications and improves cost effectiveness. The team commonly comprises a physician, nurse, dietician and pharmacist along with a GI surgeon, microbiologist, biochemist and psychologist. They aim to achieve a reduction in complications, inappropriate use of PN and improve planning of PN administration to reduce wastage. Typical nutrition requirements can be calculated in a variety of ways which recognize variations caused by metabolic stress and activity level. Generally, 20e30 Kcal/kg/day, with 1 g/kg/ day protein and 30e35 ml/kg/day fluids (excluding extra losses from fistulae, drains, etc.), is thought to be appropriate. Electrolytes and minerals including sodium, potassium, calcium, magnesium and phosphate should be addressed on an individual patient basis. Their losses should be monitored, with particular vigilance in patients with renal or liver impairment. Finally, micronutrients and vitamins also need to be considered for patients, particularly those on long term feeding.
Laboratory tests for monitoring nutrition support4 Monitoring test
Frequency
Sodium, potassium, urea, creatinine
C C C
Glucose
C C C
Magnesium phosphate
C C C
C
Liver function tests and international normalized ratio (INR) Calcium and albumin
C C C C C
CRP
C C
Zinc and copper
C C
Selenium
C C
Full blood count
C C C
Iron and ferritin
C C
Folate and B12
C C
Manganese 25-OH Vitamin D
C
Bone densitometry
C
C
C
Baseline Initially daily When stable: 1e2 times per week Baseline Initially: 1e2 per day When stable: 1 per week Baseline Initially daily Risk of re-feeding syndrome: 3 per week When stable: 1 per week Baseline Initially 2 per week When stable 1 per week Baseline Weekly Baseline When stable: 2e3 per week Baseline Depending on results: 1e2 per month Baseline (if risk of depletion) Further tests dependent on baseline Baseline Initially: 1e2 per week When stable: 1 per week Baseline Once every 3e6 months Baseline 1e2 per month Once every 3e6 months (HPN) Once every 6 months (long term support) Baseline taken at time of commencing HPN Once every 2 years
Other aspects: During the initial management phase while treating sepsis and nutrition, there are several other issues that must be addressed in order to prevent further complications and facilitate planning for definitive surgery. 1. Skin care Specialist stoma nursing care is required to manage ECF or defunctioning stomas with an appropriate appliance. ECF may cause severe skin inflammation (Figure 1) and necrosis if the alkaline fluid is allowed to stay in contact with the skin. Specialist products including pastes, skin barriers, seals, adhesive removers, absorbing agents, large volume collecting appliances and support belts all are used to prolong stoma bag life, prevent leakage and protect the skin. 2. High output stomas and ECF: ECF often act like high output stomas (HOS) due to their anatomical location. Recording accurate fluid balance is essential to management and awareness of the anatomy of the GIF and the length of proximal bowel is helpful. A pathological cause for high output should be excluded, for example partial bowel obstruction, intra-abdominal sepsis, enteritis (infective, radiation), medications (such as inappropriate use of prokinetics or recent changes to medication) or active inflammatory bowel disease. The relationship between oral intake and output can be demonstrated by fasting the patient and switching to parental nutrition and hydration. Gradual reintroduction of enteral fluids not only demonstrates high output due to oral intake, but also indicates how much reliance is needed on parenteral nutrition. It is a misconception that encouraging patients to drink large volumes of fluids will ensure hydration. Instead, this can actually stimulate huge losses of water and sodium. Fluid restriction may actually reduce losses. The type of oral fluid used is also important. Hypotonic or hypertonic solutions can cause excessive losses. In losses of 1.2 litres or more patients may be advised
Table 4
Central venous access provides a safer route for TPN administration for extended durations. Tunnelled versus non-tunnelled: Because of the distance between the skin puncture site and the entrance of the catheter into the vein, tunnelled lines carry less risk of infection and are therefore recommended in patients for long-term use (more than 30 days). Care of line Good nursing care is key to reducing septic line complications. It is recommended that dedicated lines for PN be used and nurses should be trained in aseptic technique. TPN lines should not be routinely used for blood sampling or administration of other drugs except in emergencies.
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to take isotonic solutions such as St Mark’s solution or World Health Organization Cholera solution. Drug therapy is important in HOS, particularly when oral restriction and isotonic solutions are not adequate. Anti-motility medication such as loperamide or codeine phosphate can serve to decrease sodium output by approximately one-third. Loperamide is preferred over opiates due to both the limited side effect profile and greater effect. When combined, however, the effect is further enhanced. It is important that drugs such as loperamide are administered as tablets, not capsules, which will not be absorbed in patients with IF. In these patients, doses of loperamide and codeine may be supranormal leading to problems when communicating with community doctors and pharmacists. Proton pump inhibitors should be given at high does for their anti-secretory effect. Bile acid sequestrants have been used in the treatment of high output ileostomies and could be of benefit in reduction of osmotically driven secretory diarrhoea from ECF. Somatostatin or its analogues such as octreotide may be useful in decreasing volume output. While their role is long established in pancreatic fistula, it has also been shown through a more recent systematic review that there is benefit and association with spontaneous and decreased time to closure of non-pancreatic fistulae.8 Finally, if the above methods fail it may be inevitable that some patients will need to maintain hydration by intravenous fluid and/or electrolytes and/or TPN. 3. Holistic care: Patients with GIF requiring TPN will often have had a significant period of hospitalization and be weak both physically and psychologically. Collaboration within the multidisciplinary team needs to address mobility and strength. Consideration also needs to be taken to identify psychological issues. Where possible, psychological and or psychiatric services should be made available. It is vital to ensure that the patient (and relatives) understand the serious and long-term nature of future definitive treatment of ECF so they have a realistic understanding before embarking on further surgery.
mortality if repeat surgery is undertaken in weeks 2e6. At this stage the abdomen is hostile due to the presence of early adhesions, and there is a high risk of iatrogenic damage. Therefore, provided that all sepsis is drained and there is no ischaemia or haemorrhage, surgery is often best deferred until reperitonealization has taken place and the patient’s general condition improved. As reperitonealization occurs, the abdomen becomes softer and it is common for an ECF to prolapse (Figure 2). This is a good sign that the adhesions in the abdomen will be more pliable and easier to dissect. It is common to encounter ECF patients who have been transferred between surgeons or units and have undergone multiple laparotomies over 2 to 4 weeks. The primary operation may have been for a relatively straight forward indication, e.g. appendicitis or small bowel resection, but complications have led to more technical difficulties with subsequent relook procedures. In general, it is unlikely that much can be achieved after two or three relook laparotomies. The first relook is obviously necessary to deal with anastomotic leak, ischaemia or haemorrhage and the operating surgeon may decide that a planned further procedure is necessary after 24 to 48 hours. At this second laparotomy the surgeon may deem it inappropriate to close the abdomen and plan a delayed closure. If progress is not been made by the third relook it is unlikely that anything strategic can be achieved at further laparotomies, assuming that an adequate assessment of the situation has been made at each operation. Unfortunately it is not unusual to receive patients who have undergone six to ten laparotomies during the episode, which led to the development of IF. These patients arrive in an extremely catabolic state with impairment of multiple organ systems. A considerable period of time is required to resuscitate and rehabilitate these patients such that it can easily be six months before they are ready for further surgery. Other factors affecting the decision to operate at a particular time include nutritional state, sepsis control and cardiopulmonary exercise (CPEX) testing to assess patient fitness prior to any major intervention. Once anatomy has been defined, the patient (and relatives) should be counselled regarding further definitive surgery. In some instances the risks of surgery may outweigh the inconvenience and morbidity of a relatively low output ECF, which is easy to manage with a stoma appliance and for which the patient only requires enteral nutrition. Patients with severe comorbidities may not be fit for further major laparotomy and may even prefer HPN. However, if the patient is, or can become, fit and has either a high output ECF and/or requires TPN then surgery will usually be recommended.
Definitive management Defining anatomy: If spontaneous closure of an ECF is going to occur, it is likely to do so within 6 weeks from commencement of conservative measures. After this point, spontaneous closure is unlikely, particularly in the presence of underlying disease. If definitive surgery is being considered, understanding the anatomy and relationship of the GIF to the gut and other abdominal organs is the first step in planning for reconstruction. It is also important to exclude distal obstruction and assess for underlying disease. Historically, plain X-ray contrast studies and fistulograms were the imaging methods of choice, and can still provide useful information when interpreted by an experienced clinician. CT or MR enterography are more commonly used today and are useful in establishing anatomical findings. Ultrasound has some use in repeat imaging and re-assessment of abscess cavities or other features identified by CT or MR imaging. Close collaboration with a specialist GI radiologist in this area is essential.
Procedure The steps that need to be addressed in a successful operative strategy include: safe access to the abdominal cavity resection of GIF and reconstitution of the GI tract abdominal closure the need for a defunctioning (temporary) stoma. Upon entering the abdomen the entire bowel from stomach to the rectum should be inspected and dissected free to isolate the GIF and ensure no distal obstruction is present. Measurement of the
Planning: Timing of definitive surgery is critical in determining outcome. In the authors’ experience, early intervention is ideal if a problem is identified in the first 10e14 days after initial surgery. However, there is a very high risk of further morbidity or
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be remembered that many patients may not have eaten properly for several months at this stage and the process may take several weeks, or even months. Even for those patients in whom IF is not permanent, the time spent recovering from the medical and surgical management of IF due to ECF is considerable. Patients often require many months in hospital with a period of rehabilitation in the community thereafter. These events can have a severe impact on patients both physically and mentally. Family and friends may also experience considerable strain, particularly if the patient has been transferred to a centre far from their home. Part of the role of the multidisciplinary team is to support the patient and their relatives through such a protracted and demanding process. Figure 2 Prolapsed enterocutaneous fistula.
Quality Assurance: Management of patients with IF is a complex multidisciplinary affair and there are many aspects of care which can be evaluated. Although individual patients present a unique combination of challenges, there are some common outcome measures which can be recorded: line infection rates unplanned returns to theatre GIF recurrence success in weaning from parenteral nutrition and intravenous fluid support mortality. BAPEN (British Association of Parenteral and Enteral Nutrition) and BIFA (British Intestinal Failure Alliance) have published a position statement on the quality of IF services and most UK units audit their outcomes against these standards.6
small bowel is important both before and after the GIF is excised to plan aftercare and will be useful in the event of further surgery. It is useful to document the length and condition of the small bowel plus the relative positions of any repairs, anastomoses or stomas as a structured operation note. All damaged bowel should be resected or repaired. Once the GIF and any non-viable bowel has been excised, reconstitution by one or more anastomoses should be performed, usually avoiding stapled anastomoses. Should multiple anastomoses be required, consideration must be given as to whether to defunction the patient while healing occurs. If so, a loop stoma should be fashioned to allow for a downstream contrast study prior to stoma closure. Reconstructive operations are complex in nature and long in duration. Decision making throughout the procedure will depend upon individual circumstances. Excessive haemorrhage, unsuspected sepsis, a frozen pelvis or abdomen and suspicion of malignancy are all factors which may mandate a change of plan. Basic surgical principles should be followed e stop haemorrhage, relieve obstruction and drain pus. Further iatrogenic damage carries a very poor prognosis. A high defunctioning stoma and a further period on TPN may be the least worst option for some patients. Finally, abdominal closure can create a challenge in itself and a variety of options exist, with the aim of ensuring appropriate cover of the bowel to prevent GIF recurrence, reconstruct the abdominal wall and prevent compartment syndrome. Component separation techniques can be valuable. When using mesh, it is important to select a mesh material that is going to reduce the chance of recurrence of GIF and that morbidity does not significantly increase if infection occurs. Therefore, Vicryl Ò or certain biological meshes are preferred over non-absorbable synthetic meshes.
Home TPN: For patients with type III IF, or those with type II who are awaiting surgery for a HOS or ECF, or reversal of a high defunctioning stoma, TPN may be administered at home. The nutrition support team will train appropriate patients in the practice of aseptic technique in order to connect and disconnect TPN infusions. Many patients (or a family member) can manage this independently at home. For those unable to do so, a community TPN nurse can be provided who will attend daily (if necessary) to set up and take down TPN. Blood tests should be performed (as per Table 4) in cooperation with the general practitioner or district nursing service. Home TPN patients are educated as to signs of sepsis, line complications or metabolic disturbances. They are also provided with the contact details of a TPN nurse during office hours, and the number of the gastroenterology or surgical ward in case of out of hours emergencies. Patients can be maintained on long-term TPN if necessary, but vigilance is required in order to reduce the risks of long-term thrombotic or infective line issues or worsening liver function. The mortality rate for IF patients receiving HPN should be less than 5% at 5 years. However, longer term there is a significant attrition rate due to acute sepsis, or gradually worsening liver dysfunction. Small bowel or combined liver and small bowel transplantation may be offered to some HPN patients. There is controversy as to whether patients requiring lifelong PN should be referred early (when their liver function is normal) to a small bowel transplant (SBT) unit, or whether combined transplantation should be reserved for those in whom the liver is beginning to fail. Because survival and quality of life on HPN are now so good, patients may be unwilling to embark on a risky
Recovery: Early postoperative care should take place in a critical care unit or a surgical ward with appropriately trained nurses familiar with the care of such complex cases. Strict attention to fluid balance, nutritional support, thromboembolic prophylaxis, pain relief and sepsis is essential. Early mobilization and physiotherapy is mandatory, and resumption of oral feeding is encouraged, even if the patient requires TPN because of a high defunctioning stoma. In those with sufficient intestinal length, a gradual approach is used to wean from TPN and resume full enteral intake. It should
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procedure which still has relatively high mortality rates and significant impact on quality of life postoperatively. Most IF units liaise closely with the supraregional small bowel transplant units so that appropriate patients can be discussed and referred for consultation. While SBT may be life saving in some cases, it is a major and risky procedure which should only be undertaken in specialized units after detailed assessment and counselling of patients with IF.
REFERENCES 1 Pironi L, Arends J, Baxter J, et al. ESPEN endorsed recommendations definition and classification of intestinal failure in adults. Clin Nutr 2015; 34: 171e80. 2 Jones B. Home parenteral nutrition in the United Kingdom; a position paper. The British association of Parenteral and Enteral Nutrition (BAPEN), 2003. 3 Agwunobi AO, Carlson GL, Anderson ID, Irving MH, Scott NA. Mechanisms of intestinal failure in Crohn’s disease. Dis Colon Rectum 2001; 44: 1834e7. 4 NHS commissioning, Specialised Services. 2013/14 NHS standard contract for Intestinal Failure (Adult), NHS England. A08/S/a. https://www.england.nhs.uk/wp-content/uploads/2013/06/a08intestinal-failure-adult.pdf (Accessed August 2017). 5 NICE nutrition support in adults: oral nutrition support, enteral tube feeding and parenteral nutrition. Feb 2006 (last updated August 2017). NICE clinical guideline 32, guidance.nice.org.uk/cg32. 6 http://www.bapen.org.uk/nutrition-support/parenteral-nutrition/ position-statement-from-bifa-committee. 7 Nightingale J, Woodward JM. Guidelines for management of patients with short bowel. On behalf of the Small Bowel and Nutrition Committee of the British Society of Gastroenterology. Gut BMJ Aug 2006; 4: 1e12. 8 Stevens P, Foulkes RE, Hartford-Benyon JS, Delicata RJ. Systematic review and metaanalysis of the role of somatostatin and its analogues in the treatment of enterocutaneous fistula. Eur J Gasteroenterol Hepatol 2011 October; 23: 912e22.
Summary IF is a very serious condition which is commonly due to GIF. Patients require the services of a multidisciplinary nutrition support team in order to optimize all aspects of their care. At presentation, many patients are acutely unwell with life-threatening septic and metabolic complications, which should be addressed urgently. Definition of anatomical features should be part of the planning for restorative surgery. Major restorative surgery should be undertaken when the patient is stable, and consideration should be given to the use of a high defunctioning stoma to cover any anastomoses. IF patients require significant attention to detail medically, and psychological support from the MDT in order to get through a prolonged episode of ill health. A
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