Current Management of Short
`Bowel Syndrome
`
`Intestinal failure refers to a condition that results from obstruction,
`dysmotility, surgical resection, congenital defect, or disease-associated
`loss of absorption and is characterized by the inability to maintain
`protein-energy, fluid, electrolyte, or micronutrient balance.1 The short
`bowel syndrome (SBS) is a type of intestinal failure caused by intestinal
`resection leading to a shortened intestinal remnant and is characterized by
`the inability to maintain protein-energy, fluid, electrolyte, or micronutri-
`ent balances when on a conventionally accepted, normal diet. SBS
`accounts for approximately three-fourths of intestinal failure patients in
`adults and more than one half in children. The pathophysiologic changes
`that occur in SBS relate primarily to the loss of intestinal absorptive
`surface and more rapid intestinal transit. The consequences of malabsorp-
`tion of nutrients include malnutrition, diarrhea, steatorrhea, specific
`nutrient deficiencies, and fluid and electrolyte imbalance. These patients
`are at risk for other specific complications, which include an increased
`incidence of cholelithiasis, gastric hypersecretion, nephrolithiasis, and
`liver disease.
`The history of SBS is one of long-standing interest but more recent
`advancements. Koeberle2 reported the first patient surviving massive
`resection of the small intestine in 1880. The clinical consequences of
`diarrhea and malabsorption were described by Senn in 1888.3 Mall4
`reported using reversed intestine segments to improve these symptoms in
`1896. Functional adaptation after massive resection was well documented
`by Flint5 in 1912. In 1935, Haymond6 reviewed 257 cases of extensive
`(⬎8 feet resected) intestinal resection. He found that only 50 (20%)
`survived for more than 1 year and further suggested that loss of 50% of
`the intestine was the upper limit of safety. Simons and Jordan7 reported
`90 SBS patients (⬍4 feet remaining small intestine) in 1969. Mesenteric
`vascular disease was the most common diagnosis and mortality remained
`high. An important milestone was the demonstration by Wilmore and
`Dudrick in 1968 that parenteral nutrition (PN) would support nutritional
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`Curr Probl Surg 2012;49:52-115.
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`status in SBS patients.8 The development of home PN in 1970 revolu-
`tionized the long-term care of SBS patients and this modality rapidly
`became standard therapy.9,10 More recently, the importance of optimal
`diet and potential pharmacologic therapy was introduced by Byrne and
`colleagues,11 leading to the concept of intestinal rehabilitation. In 1990,
`Grant and colleagues12 reported the first long-term survivor of a small
`bowel transplant who achieved enteral autonomy, ushering in a new
`avenue of treatment for SBS.
`The incidence and prevalence of SBS are estimated to be 3 per million
`and 4 per million, respectively.13 Thousands of patients are now surviving
`with SBS.14 This condition occurs in approximately 15% of adult
`patients undergoing intestinal resection, with three fourths of these
`cases resulting from massive intestinal resection and one fourth from
`multiple sequential resections.15 Massive intestinal resection contin-
`ues to be associated with significant morbidity and mortality rates,
`which are related primarily to the underlying diseases necessitating
`resection.15,16 Approximately 70% of patients who develop SBS are
`discharged from the hospital.16 The overall 5-year survival is 75% for
`those leaving the hospital.17 This improved survival rate has been
`achieved primarily by the ability to deliver long-term nutritional
`support. The overall outcome of these patients is often determined not
`only by their age and underlying disease but also by complications
`related to management of SBS.
`SBS has been the topic of previous issues of Current Problems of
`Surgery. In 1971, Wright and Tilson highlighted the pathophysiology of
`SBS as management options were limited at that time.18 Wilmore and
`colleagues19 in 1997 emphasized new therapeutic approaches, particu-
`larly promising pharmacologic agents. This led to the concept of intestinal
`rehabilitation and the development of multidisciplinary teams. The
`current monograph reviews recent advances in our understanding of
`pathophysiology, medical management, and surgical therapy, especially
`intestinal transplantation.
`
`Etiology of the Short Bowel Syndrome
`).
`A variety of conditions requiring intestinal resection lead to SBS (
`The causes of SBS vary by age group. In infants, necrotizing enterocolitis
`is the most common cause of SBS, followed by intestinal atresia,
`gastroschisis, and midgut volvulus.20 In older children, postoperative SBS
`and malignancies become important reasons for resection. Trauma and
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`TABLE 1. Causes of the short bowel syndrome
`Infants
`Necrotizing enterocolitis
`Intestinal atresia
`Gastroschisis
`Midgut volvulus
`Children
`Cancer
`Postoperative complication
`Trauma
`Motility disorders
`Adults
`Postoperative complications
`Irradiation/cancer
`Mesenteric vascular disease
`Crohn’s disease
`Trauma
`Other benign causes
`
`motility disorders requiring resection are also potential mechanisms for
`SBS in this age group.
`The etiology of SBS in adults may be changing. We have found that
`postoperative SBS, resection performed for complications of previous
`abdominal operation, has become the most common cause in adults.21 This
`occurs after both open and laparoscopic procedures. Although this may be
`related to infarction secondary to vascular injury, volvulus, or hypotension, it
`most commonly occurs because of intestinal obstruction. Mesenteric isch-
`emia remains an important predisposing factor. Mesenteric vascular disease
`is the common mechanism but ischemia secondary to drug abuse and
`hypercoagulable disorders is increasingly found. Malignancy, with or without
`radiation treatment, also accounts for a significant number of cases. Crohn’s
`disease remains responsible for a significant number of SBS patients but may
`be declining with less aggressive resective therapy. Resection for trauma and
`other benign conditions, such as volvulus and intestinal pseudoobstruction,
`are other potential causes for SBS.
`Prevention of the Short Bowel Syndrome
`Prevention of SBS is an important consideration given the morbidity
`and mortality associated with long-term treatment. Efforts at prevention
`can be divided into 2 periods: preoperative and intraoperative.
`Preoperative strategies to prevent SBS are primarily related to the
`patient’s underlying diagnosis. Postoperative SBS could be minimized by
`employing strategies to present adhesions, avoiding technical errors,
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`diagnosing intestinal ischemia in a timely fashion, and approaching the
`frozen abdomen cautiously.21 Patients undergoing bariatric procedures
`should have mesenteric defects closed to prevent internal hernias and this
`diagnosis should always be entertained when these patients experience
`abdominal pain.22 Unsuspected intestinal ischemia is increasingly recog-
`nized as a complication of laparoscopic procedures.23 Intestinal ischemia
`from mesenteric vascular disease and hypercoagulability must be diag-
`nosed in a timely fashion. This may permit attempts at revascularization.
`Intestinal viability should be carefully assessed intraoperatively and
`second-look procedures should be used judiciously.24 Radiation enteritis
`can be reduced by minimizing bowel exposed to radiation.25 Errors in
`diagnosis, aggressive resectional therapy, and postoperative complica-
`tions contribute to SBS in patients with Crohn’s disease.26,27 SBS can be
`minimized in trauma patients by early diagnosis of vascular injuries, use
`of second-look procedures, and appropriate resuscitation.28 Bowel-pre-
`serving strategies are now being used in infants with necrotizing entero-
`colitis, which may decrease the incidence of SBS because of this
`condition.29
`There are several intraoperative strategies to prevent SBS.30 The extent
`of resection should always be minimized where possible. Tapering or
`lengthening dilated segments and use of stricturoplasty in conditions such
`as Crohn’s disease can obviate the need for resection. Avoiding extensive
`enterolysis and using cautious resection can prevent SBS in patients with
`extensive adhesions from conditions, such as radiation enteritis.25
`
`Factors Influencing Outcome
`The clinical manifestation of SBS varies greatly among patients,
`depending on intestinal remnant length, location, and function; the status
`of the remaining digestive organs; and the adaptive capacity of the
`intestinal remnant (Fig 1). More recently the importance of other
`patient-related factors has also been recognized, including age, diagnosis,
`and body mass index.16,31 Thus, although intestinal length is important,
`the outcome of SBS is not entirely dependent on a given length of
`remaining intestine.
`Intestinal remnant length is the primary determinant of outcome in SBS.
`The length of the small intestine reported in adults varies between 12 and
`20 feet (360-600 cm), depending on how it is measured and the height and
`sex of the individual.32-34 The duodenum measures 10-12 inches (25-30
`cm). The length of the small intestine from the ligament of Treitz to the
`ileocecal junction is generally approximately 16 feet (480 cm), with the
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`FIG 1. Factors affecting the outcome of short bowel syndrome.
`
`proximal two fifths being jejunum and the distal three fifths being ileum.
`Resection of up to one half of the small intestine is generally well
`tolerated. Although adult patients with less than 180 cm of small intestine,
`approximately one third the normal length, may develop SBS, permanent
`PN support is likely to be needed in patients with less than 120 cm of
`intestine remaining without colon in continuity and less than 60 cm
`remaining with colonic continuity.17,35
`In infants, the intestinal length is 125 cm at the start of the third
`trimester and 250 cm at term. The length then doubles again as the child
`reaches adulthood.20,36 Children with less than 75 cm small intestine may
`develop SBS. Children are further classified as short small bowel (⬎38
`cm), very short small bowel (15-38 cm), and ultrashort small bowel (⬍15
`cm).20 These categories predict those that are most likely to become
`PN-independent and survival vs need for PN and mortality.
`The site of resection is also an important factor. Patients with an ileal
`remnant generally fare better than those with a jejunal remnant. The ileum
`has specialized absorptive properties for bile salts and vitamin B12,
`unique motor properties that prolong transit time, a hormone profile
`different from the jejunum, and a greater capacity for intestinal
`adaptation.37,38 L cells in the terminal ileum secrete several hormones
`that might
`influence appetite, gastrointestinal motility,
`intestinal
`absorption, and intestinal adaptation, including peptide YY, neuroten-
`sin, and glucagon-like peptides 1 and 2 (GLP-1 and GLP-2). The
`presence of the ileocecal junction improves functional capacity of the
`remnant.38 Although previously this had been largely
`intestinal
`attributed to a barrier function and transit prolonging property of the
`ileocecal valve, this advantage may actually be related to the special-
`
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`FIG 2. Intestinal anatomy in short bowel syndrome Type 1 anatomy (left) is a proximal jejunostomy.
`Type 2 anatomy (center) is a jejunocolostomy. Type 3 anatomy (right) is a jejuno-ileo-colostomy.
`
`ized properties of the terminal ileum itself, which is usually resected
`with a loss of the ileocecal junction.
`The status of the other digestive organs also contributes to the outcome.
`The stomach influences oral intake, mixing of nutrients, transit time,
`pancreatic secretion, and protein absorption. Pancreatic enzymes are
`important in the digestive process and particularly influence fat absorp-
`tion. The colon absorbs fluid and electrolytes, slows transit, and partici-
`pates in the absorption of energy from malabsorbed carbohydrates.39 The
`colon will absorb up to 15% of the daily energy requirements and thereby
`reduce PN needs.39-41 Compared with an end jejunostomy (Type 1
`anatomy), a jejunoileal anastomosis with an intact colon (Type 3
`anatomy) is equivalent to 60 cm of additional small intestine, and a
`jejunocolic anastomosis (Type 2 anatomy) is equivalent to approximately
`30 cm of additional small intestine35 (Fig 2). The importance of the colon
`in functional adaptation of infants is less clear but appears to be critical
`in children with very short and ultrashort small bowel.42
`The underlying disease leading to resection is an important patient-
`related outcome factor. Patients with inflammatory disease (eg, Crohn’s
`disease and radiation injury) in the intestinal remnant may have impaired
`intestinal function. They may also be at increased risk of hepatobiliary
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`FIG 3. Schematic presentation of intestinal adaptation. SA, spontaneous adaptation; AA, accelerated
`adaptation, HA, hyperadaptation; AHA, accelerated hyperadaptation. (Reprinted with permission
`from Jeppesen.44)
`
`disease.43 The cause of resection will also influence outcome because of
`the effect on other digestive organs. Patients with malignancy and trauma
`often have involvement of other organs.28
`Long-term treatment and survival are influenced by the patient’s age
`and other medical conditions. Infants and young children have the
`potential for intestinal growth but typically have caloric needs 2 to 3 times
`those of adults to support normal growth and development.20 Elderly
`patients generally have a less favorable outcome.17 Paradoxically, obesity
`has also been recognized recently as an important positive determinant of
`SBS outcome.31
`
`Intestinal Adaptation
`The small intestine has the ability to adapt to compensate for the
`reduction in absorptive surface area caused by intestinal resection.19,44,45
`This adaptive process occurs within the first year or 2 after resection in
`adults and improves intestinal absorptive capacity (Fig 3).44 Intestinal
`failure is considered permanent when specialized nutritional support is
`required beyond this initial 2-year period. Whether or not the adaptive
`response can be significantly accelerated or augmented (hyperadaptation)
`pharmacologically is uncertain but is 1 of the main goals of intestinal
`rehabilitation. Intestinal adaptation in children is influenced by growth
`and development and thus occurs over a longer period in younger
`children.20 The overall intestinal adaptive response results from changes
`in intestinal structure, absorptive function, and motility.
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`FIG 4. Morphologic structures of
`permission from Wilmore et al.19)
`
`the small bowel
`
`that
`
`increase surface area. (Reprinted with
`
`Structural adaptation after intestinal resection involves all layers of the
`intestine.19,45 The intestine is not simply a cylindrical tube but contains
`folds (the folds of Kerkring) lined with finger-like villi composed of
`enterocytes, which are covered by microvilli. All of these structures
`contribute to the overall absorptive surface area (Fig 4). Mucosal DNA,
`protein synthesis, and crypt cell proliferation are increased within hours
`after resection. The total number of cells, the proportion of proliferating
`cells, and number of stem cells are increased in the crypt.46 Villus
`lengthening occurs by overall increased number of cells as enterocytes
`migrate at a faster rate along as the villus. Interestingly, rates of apoptosis,
`or programmed cell death, increase in both crypt and villus enterocytes
`after resection. However, the proliferative stimulus dominates so that
`structural adaptation occurs. An expansion of intestinal progenitors and
`putative stem cells precedes crypt fission and an increase in the ratio of
`crypts to villi.47 Microvilli along the epithelial surface also increase.
`Overall, the mucosal weight increases and mucosal folds enlarge. The
`colon may also undergo structural adaptation after intestinal resection.48
`The thickness and length of the muscle layers also increase after
`resection. This results primarily from hyperplasia rather than hypertrophy
`of the muscle cells.45 Muscle adaptation, however, occurs at a later time
`and only after more extensive resection than does mucosal adaptation.
`These changes in the components of the intestinal wall result in marked
`thickening of the intestinal wall as well as increased intestinal circum-
`ference (circular muscle) and length (longitudinal muscle). Thus, there is
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`an overall increase in mucosal surface area because of the increases in
`length and circumference of the remnant, villus hypertrophy, and in-
`creased microvilli length. These structural changes are more striking in
`experimental models than they are in humans.49
`Intestinal motor activity is also altered by intestinal resection and is a
`biphasic motor response to varying degrees of distal resection.50,51 Initial
`disruption of motor activity is followed by adaptation. Motility recordings
`in the canine small intestine are initially dominated by recurring bursts of
`clustered contractions in the distal segment of the intestinal remnant after
`limited resection and more generally after 75% resection.51 These clusters
`are prolonged and associated with baseline tonic changes with extensive
`resection. With more limited resection, there is evidence of progressive motor
`adaptation with eventual slowing of transit and return of migrating motor
`complex cycling. This adaptation is less apparent after massive resection and
`is more prominent in the jejunum than in the ileum. These motility changes
`are accompanied by modest alterations in smooth muscle contractility.
`Clinical reports also demonstrate a biphasic adaptive motor response
`during the first year after resection. There is disrupted motor activity
`in the first few months after resection, but these changes occur only
`after extensive resection (remnant shorter than 100 cm). Long-term
`human studies demonstrate a shorter duration of the migrating motor
`complex cycle and fed pattern after resection.52
`Functional adaptation clearly occurs after resection.19,52,53 This is due
`in part to structural adaptation, which increases intestinal absorptive
`surface area. Both structural and motor adaptation leads to prolonged
`transit time, which will improve absorption. Although previously im-
`proved absorption by individual enterocytes has been discounted, more
`recent studies suggest improvement in certain transport capabilities.54
`There is evidence that there is up-regulation of the total number of
`transporters and an increase in intrinsic activity for transporters, particu-
`larly for glucose absorption, but this remains controversial.54,55 Brush
`border enzyme activity also increases. Overall, the effect of these changes
`is that diarrhea diminishes, absorption increases, and nutritional status
`improves within months of resection.
`Less well understood are any adaptive changes in the immune and
`barrier functions of the intestinal remnant during adaptation. In experi-
`mental studies, intestinal intra-epithelial lymphocytes shift to a more
`immature and less activated cell population.56 Bacterial translocation to
`lymph nodes and peripheral blood is increased with massive resection.57
`Changes in immune and barrier function in adult SBS patients are not
`well studied.
`
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`TABLE 2. Factors influencing intestinal adaptation
`Luminal factors
`Gastrointestinal regulatory peptides
`Nutrients
`Secretions
`Systemic factors
`Cytokines
`Growth factors
`Hormones
`Tissue factors
`Immune system
`Mesenchymal factors
`Mesenteric blood flow
`Neural influences
`
`The mechanism of intestinal adaptation has been studied extensively but
`is still not entirely understood. The degree of structural adaptation is
`related to the extent and site of resection.19,45 Adaptation is greater with
`more extensive resections and the ileum has a greater adaptive capacity
`than jejunum. Subsequent resection elicits a further adaptive response.
`Luminal nutrients, secretions, and growth factors are important
`in
`achieving the maximal response but are not essential for adaptation to
`occur (Table 2).19,45
`The early molecular events associated with this hyperplastic response
`are being investigated.58-63 Intestinal resection results in increased levels
`of a variety of gene products in crypt and villus enterocytes within hours.
`There is an immediate increase in genes influencing cell proliferation,
`nutrient absorption and trafficking, and cellular homeostasis. Many of
`these are novel genes, not normally present in intestinal epithelium. This
`molecular response is spatially and temporally regulated. Proteomic
`analysis has also been performed after resection and many proteins are
`increased.60 Proteins, such as fatty acid (FA) binding protein, may prove
`useful in monitoring the adaptive response. The specific triggers for these
`events are not clear, but there are many candidates. Gene expression is
`regulated by growth factors in a specific fashion [eg, epidermal growth
`factor (EGF) and GLP-2 but not Insulin-like growth factor (IGF)-1
`up-regulate PC4 expression61 and early but not late administration of
`GLP-2 expands progenitor cells].47 Currently there is great clinical
`interest in manipulating the adaptive response pharmacologically.
`
`Medical Rehabilitation
`The medical management of SBS requires tailoring to the clinical stage
`of the patient following massive intestinal resection. The early acute
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`FIG 5. Multidisciplinary management of short bowel syndrome.
`
`phase (1-3 months) involves stabilization of large fluid and electrolyte
`losses, maintaining fluid balance, and controlling acid/base balance.
`Diarrhea is generally severe during this period and enteral absorption is
`limited; therefore, PN support is required as the patient rebuilds stamina
`and recovers from surgical resection. Long-term vascular access must be
`established in this phase. During the intermediate phase (up to 24
`months), the focus is placed on balancing nutrition support with the
`potential to begin PN reduction as enteral absorption improves based on
`clinical parameters of weight, oral intake, renal function, and hydration
`status. The use of medical treatments to maximize the absorptive capacity
`of the remaining intestine and prevention of the complications related to
`both the underlying pathophysiology and the nutritional therapy requires
`intensive monitoring. In the last phase (⬎24 months), continued efforts
`toward complete PN weaning should be attempted. However, in some
`patients stabilization may be reached and no further improvement in
`functional adaptation may be demonstrated.
`The overall goal of medical rehabilitation is to return patients to as
`normal a lifestyle as possible with as little dependence on PN as can be
`achieved. Intestinal rehabilitation is the process of enhancing intestinal
`absorption and function through the use of modified diet, enteral nutrition,
`oral rehydration solution, motility and antisecretory agents, antibiotics,
`and enterotrophic medications.
`A multidisciplinary approach is required for comprehensive and optimal
`care of patients with intestinal failure64-68 (Fig 5). Expertise in the
`management of gastrointestinal disease, gastrointestinal surgical expertise
`for both children and adults, and ideally, organ transplantation provide the
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`appropriate therapeutic options. Nutritionists, nurse coordinators, psy-
`chologists, and social workers are also critical members of the team.
`Support from consultants, such as endocrinologists and appropriate
`radiologic and laboratory services, is called on as needed. Administrative
`support to coordinate this process and to maintain a clinical database is
`also required. Several reports have demonstrated the benefits of this
`multidisciplinary effort on patient outcome and early referral
`to an
`intestinal rehabilitation center is suggested.64-68
`
`Maintaining Nutritional Status
`The main therapeutic objective in the management of SBS is to
`maintain the patient’s nutritional status as defined in adults by a target
`body mass index of 20 to 25 kg/mg2 and normalized macro- and
`micronutrient status. Most adult patients require 25 to 30 kcal/kg per day
`and 1.0 to 1.5 grams of protein per kilogram per day with appropriate
`additives. Goals in infants and children are age-specific and nutritional
`support in these patients has been recently summarized.69 Maintenance of
`nutritional status requires in most instances continuous PN support in the
`early period after operation.
`The appropriate composition of PN is based on age, body weight, and
`underlying condition. The presence of concurrent morbidities, such as
`hepatic, renal, pancreatic, pulmonary, or cardiovascular disease, calls for
`individual tailoring of the PN orders. Attention and frequent monitoring
`to the individual patient’s requirement for optimal fluid replacement and
`electrolyte replacement is imperative. Enteral nutritional (EN) support via
`nasojejunal access or percutaneous enteral access should be started as
`soon as possible followed by careful monitoring of the patient’s response
`and improvement in adaptation. If the patient can accomplish enteral
`intake, it should be 1500 mL greater than gastrointestinal tract output,
`which would allow for 1000 mL of urine output and 500 mL of insensible
`fluid loss.
`Although the traditional view has been that EN should be held until
`bowel function has resumed, several clinical studies have challenged this
`traditional view and now support the early provision of EN for surgical
`patients in general within 24 to 48 hours of surgery.70 Even in the strict
`nil per os (NPO) setting the fasting gastrointestinal tract is exposed to 500
`to 1000 mL of gastric secretions daily complemented by 1 to 2 L of
`biliopancreatic secretions regardless of enterally administered nutrition.
`The presence of luminal nutrients results in postprandial hyperemia,
`which in turn prevents mucosal atrophy, attenuates the stress response,
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`maintains immunocompetence, preserves the gut flora, is associated with
`fewer septic complications, and is associated with cost savings.71-74 Early
`EN in patients with SBS should have additional benefit in terms of
`intestinal adaptation but restrictions apply to hyper- and hypoosmolar
`solutions in SBS patients.
`With time, an increasing amount of nutrients is absorbed by the enteral
`route. This is important for maximizing intestinal adaptation and allow-
`ing gradual reduction of PN. As the patient’s condition improves and
`intestinal adaptation occurs, many patients can absorb the necessary
`nutrients entirely by the enteral route while becoming to a certain extent
`hyperphagic.75,76 Enteral independence, defined as the ability to maintain
`adequate caloric intake without need for PN, is determined by (1) residual
`length of small bowel, (2) continuity of small bowel with large bowel, (3)
`presence of ileocecal valve, (4) the ability to respond with a certain degree
`of hyperphagia,75,76 and (5) the presence or absence of a stoma.
`Classifying the patient into 1 of 3 anatomic types described earlier (Fig 2)
`helps to a certain extent predicting who will eventually wean from PN.
`Patients with more than 180 cm of small intestine remaining generally
`require no PN; those with more than 90 cm and colon in continuity will
`require PN for less than 1 year; and those with less than 60 cm of small
`intestine will likely require permanent PN, depending on the length of
`colon remaining.
`Although initially administered continuously, PN can be switched to
`cyclical administration as soon as there is enteric intake by mouth or other
`stated routes. Continuous PN is given in the early phase, whereas cyclic
`PN will predominate the intermediate and late phases. Cyclic (discontin-
`uous) PN is more convenient in adults. A recent review of 25 clinical
`studies in children and adults recieving long-term PN emphasizes the
`favorable risk-benefit profile of cyclic PN.77
`in
`The need for prolonged PN in patients with SBS can result
`considerable societal costs (expenses, clinic visits, loss of time at work for
`caregivers) and morbidity and mortality. The quality of life is negatively
`affected and restrictions on travel can be onerous for PN patients. The
`very regimented lifestyle of a patient with SBS with 12 to 18 hours of PN
`infusion and line care poses major social life, travel, and professional
`restrictions. Published data on the quality of life assessment for patients
`on PN were recently reviewed by Richard and Carlson,78 Winkler,79
`Howard,80 and Huisman-de Waal and colleagues.81 Assessment of
`quality of life must include emotional, physical, occupational, and social
`data. The European Quality of Life Instrument (EuroQoL) index offers a
`scale from 0 to 100 and examines the domains of mobility, self-care, main
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`activity, social relationships, pain, and mood.78 Lowest scores of 50 to 60
`are usually reported in the first year on PN assuming that the patient was
`previously in good health. Rising scores to 60 to 70 are reported after 4
`to 5 years of therapy, with a score of 100 presenting the normal healthy
`population.78 Three studies applying other quality of life instruments have
`reported on the decrease in quality of life in several domains while
`receiving PN.82-84
`Although long-term PN certainly affects quality of life, SBS patients
`have additional anatomic issues (eg, stoma) and other medical
`conditions which further impact quality of life. A specific validated
`quality of life instrument for patients with SBS did not exist until
`recently based on a review of psychometric studies in patients on
`PN.85,86 In 2010, Baxter and colleagues published a provisional
`questionnaire that was administered to 100 adult patients receiving
`home PN that showed high compliance rate and was well received by
`patients.87
`The patients with SBS very often face complex psychosocial adjustment
`problems, which can be challenging to manage. Problems, such as grief
`reactions, depression, organic brain syndromes, drug dependency, and
`body image changes, have been described.88 A number of home PN
`patients have been noted to use their central venous catheter for
`self-harm.89 The impact of the chronic illness on the caregiver should also
`not be underestimated. Stressed families face additional worries because
`of the variability of PN expenses.90,91 The cost of PN ranges from
`$75,000 to $150,000 per year depending on nutritional requirements and
`does not incorporate indirect costs, such as travel to appointments and
`opportunity costs of caregivers.92
`for patients
`Several studies have addressed long-term survival
`receiving PN.17 Messing and colleagues found that patients without
`malignancy requiring long-term PN have 1-, 3-, and 5-year survival
`rates of approximately 90%, 70%, and 60%, respectively.17 Survival
`was negatively affected by end enterostomy, small bowel length ⬍50
`cm, and mesenteric ischemia as an etiology. Recent data from Italy
`have showed an actuarial survival rate of patients with intestinal
`failure of 88% and 78% at 3 and 5 years, respectively, which was
`influenced by the length of remnant intestine, age at the start of home
`PN, enteral independence, and, to some extent at least, the primary
`disorder.93 Mortality in these patients is one third due to the
`underlying disease, in 50% due to other supervening illnesses, and in
`10% to 15% because of PN therapy.
`
`Curr Probl Surg, February 2012
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`65
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`Page 14
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`
`TABLE 3. Complications of short bowel syndrome and therapy
`Catheter related
`Infection
`Loss of vascular access
`Hepatobiliary
`Intestinal failure associated liver disease
`Cholelithiasis
`Metabolic
`Fluid and electrolyte abnormalities
`D-Lactic acidosis
`Micronutrient deficiency
`Metabolic bone disease
`Osteoporosis and osteomalacea
`Renal
`Chronic renal failure
`Nephrolithiasis
`Gastrointestinal
`Gastric hypersecretion
`Small bowel bacterial overgrowth
`Changes in colonic flora
`
`Preventing Complications
`Patients with SBS are at increased risk for a variety of complications
`related to their underlying disease, pathophysiologic changes of SBS, and
`nutritional therapy. The complications are outlined in
`. Prevention
`of complications is important for improving quality of life, reducing
`costs, and improving long-term survival. Changes in therapy or administra-
`tion of PN require careful monito