Best Practice & Research Clinical Gastroenterology
`Vol. 18, No. 5, pp. 977–992, 2004
`doi:10.1016/j.bpg.2004.05.002
`available online at http://www.sciencedirect.com
`
`12
`
`Management of the short bowel syndrome
`after extensive small bowel resection
`
`Jutta Keller1
`
`MD
`
`Heidi Panter1
`
`Peter Layer* MD, PhD
`Professor of Medicine, Head of the Department of Internal Medicine
`
`Israelitic Hospital, Orchideenstieg 14, 22297 Hamburg, Germany
`
`Short bowel syndrome (SBS) is a global malabsorption syndrome that results from extensive
`intestinal resections. It used to be a typical complication of repetitive bowel resections in patients
`with Crohn’s disease. However, due to improved medical and surgical therapies for these patients
`it currently occurs more frequently as a consequence of vascular disorders in adults (intestinal
`infarction) and congenital aberrations in children, respectively. Adequate therapy depends on the
`degree of (small) bowel losses and on resulting functional disturbances. Moreover, it must be
`adjusted to the postoperative adaptation process, which consists of three phases: The immediate
`acute phase lasts less than 4 weeks and serves to stabilise the patient. The subsequent year should
`be used to induce maximal adaptation by gradually increasing nutrient exposure. When maximal
`stimulation of nutrient absorption has been achieved, permanent maintenance nutrition
`treatment should be defined individually, dependent on extent and quality of nutritive deficits.
`In patients with Crohn’s disease, optimal treatment of the underlying disease is of pivotal
`importance in order to avoid a further reduction of absorptive capacity or other complications.
`Current investigations aim at improving the adaptation process by administration of specific diets
`and growth hormones. With these, it appears possible to treat even some patients with very
`short bowel,
`i.e.
`less than 50 cm of small
`intestine left, with oral nutrition, only. Still, a
`considerable proportion of patients will need long-term parenteral nutrition. If young patients
`experience intolerable complications of parenteral nutrition, intestinal transplantation may be
`considered as a high risk therapy of last choice.
`
`Key words: short bowel syndrome; malabsorption; intestinal resections; Crohn’s disease; acute
`phase; intestinal adaptation; maintenance treatment; oral/enteral/parenteral nutrition; vitamin
`supplementation; growth hormones; glutamine; drug therapy; intestinal transplantation.
`
`* Corresponding author. Tel.: C49-40-5112-5211; Fax: C49-40-5112-5227.
`E-mail addresses: keller@ik-h.de (J. Keller), panter@ik-h.de (H. Panter), layer@ik-h.de (P. Layer).
`1 Tel.: C49-40-51125-315; Fax: C49-40-51125-413.
`
`1521-6918/$ - see front matter Q 2004 Published by Elsevier Ltd.
`
`Page 1
`
`

`
`978 J. Keller, H. Panter and P. Layer
`
`The short bowel syndrome (SBS) is a global malabsorption syndrome due to insufficient
`absorptive capacity and/or disturbed gastrointestinal regulation resulting from
`extensive small bowel resections. SBS may occur after resection of more than 50%
`and is obligatory after resection of more than 70% of the small intestine or if less than
`100 cm of small bowel are left. It is particularly severe after resection of the ileocecal
`region or if the colon has been removed additionally. Apart from global malnutrition,
`clinical symptoms may be caused by specific deficiencies depending on the site of
`intestinal loss.
`In the past, repetitive intestinal resections in patients with Crohn’s disease were the
`main cause of SBS. However, because of the improvements of conservative and surgical
`therapy of Crohn’s disease, SBS in adult patients now occurs more frequently as a result
`of vascular disorders (embolism/thrombosis of the superior mesenteric artery/throm-
`bosis of the mesenteric veins) or intestinal strangulation (volvulus,
`incarceration).
`Rarely, traumas necessitate extensive bowel resections.
`In children congenital
`aberrations (e.g.
`intestinal atresia, aganglionosis, malrotation) or necrotising enter-
`ocolitis are the predominant causes of SBS.
`There are no exact current data regarding the incidence and prevalence of SBS.
`However, data derived from patients receiving home parenteral nutrition (which in
`about one-third of the cases is necessary because of SBS) indicate an incidence of
`severe SBS of 1–2 cases per 100,000 inhabitants per year.1
`Progresses in modern surgery as well as in intensive care have crucially improved the
`prognosis of patients with SBS. The adequate therapy depends on the degree of (small)
`bowel
`losses and of resulting functional disturbances and is adjusted to the
`postoperative adaptation process, which comprises three phases:
`
`A. Acute phase:
`† starts directly after resection
`† generally lasts less than 4 weeks
`† serves for the patient’s stabilisation.
`
`B. Adaptation phase
`† lasts 1–2 years
`† maximal stimulation of
`intestinal adaptation is achieved by gradually increasing
`intestinal nutrient exposure.
`
`C. Maintenance phase
`† follows adaptation phase
`† permanent dietetic treatment must be individualised
`† effective therapy of acute exacerbations and optimal maintenance therapy of Crohn’s
`disease are of pivotal importance.
`
`life.2 Longtime therapy,
`Not surprisingly, SBS is associated with low quality of
`which should aim at the patient’s social reintegration,
`is a demanding challenge
`to the treating physician. This is due to severe and interacting metabolic changes
`after extensive small bowel resection which may be even more severe in patients
`with preexisting inflammatory bowel disease. An additional
`impairment of
`
`Page 2
`
`

`
`Management of the short bowel syndrome after extensive small bowel resection 979
`
`the absorptive capacity by progression of the underlying illness must be avoided, if
`possible.
`
`% The short bowel
`is a malabsorption syndrome due to
`syndrome (SBS)
`insufficient absorptive capacity and/or disturbed gastrointestinal
`regulation
`resulting from extensive bowel resections.
`% The incidence of severe SBS is estimated to be 1–2 per 100,000 inhabitants.
`
`PATHOPHYSIOLOGICAL BASIS
`
`Quantitative loss of absorptive capacity
`
`The small bowel owns a large functional reserve capacity. Thus, resection of up to 50%
`of the small bowel is usually tolerated without any symptoms, and in most patients
`resection of up to 50–70% leads to transient malabsorption, only. However, a residual
`length of the small bowel of less than 200 cm may result in SBS, and if less than 70–
`100 cm of small bowel are left (resection of more than 70–80%) almost all patients
`develop SBS. Moreover, almost all patients with less than 60 cm of small bowel need
`long-term parenteral nutrition. However, not only the length of the remaining small
`bowel decides about the severity of symptoms but also the absence or presence of the
`colon. In SBS patients, the colon adopts important digestive functions (absorption of
`short-chain fatty acids as an energy source) and increases absorption of water and
`electrolytes so that more extensive small bowel losses can be tolerated.
`
`% SBS is obligatory after resection of more than 70% of the small intestine or if less
`than 100 cm of small bowel are left.
`% Additional resections of the ileocecal region or the colon increase severity.
`
`Qualitative loss of absorptive capacity
`
`Moreover, not only overall extension of bowel resections but also the resection of
`specific intestinal sites influences the development of SBS. Losses of the duodenum or
`the terminal ileum, in particular the ileocecal valve, impair absorption much more than
`loss of other parts of the small bowel. This is due to the fact that both, the duodenum
`and the ileocecal region possess specific absorptive functions and play a crucial role in
`the regulation and integration of postprandial gastrointestinal motility and secretion.
`These functions may not or only partly be replaced by other parts of the small bowel.
`Diarrhoea and steatorrhoea, the cardinal symptoms of SBS, are caused by low
`absorptive capacities for water, electrolytes and nutrients. In patients with 60–100 cm
`of small bowel left and preserved colon, about 70% of applied energy is reabsorbed, but
`absorption of individual food components may vary.3,4 While proteins are absorbed by
`60–70%, malabsorption of fat and carbohydrates may reach 50% of ingested nutrients.
`Carbohydrate malabsorption is of limited importance in patients with preserved colon
`because up to 80% of carbohydrates not absorbed by the small bowel can be absorbed
`after bacterial metabolism to short chain fatty acids and thus contribute to energy
`supply.5 By contrast, fat malabsorption not only leads to steatorrhoea and malnutrition
`but is also associated with deficiencies of the fat soluble vitamins A, D, E and K.
`
`Page 3
`
`

`
`980 J. Keller, H. Panter and P. Layer
`
`Vitamins B1, B2, B6 and C are absorbed by the entire small bowel, therefore
`deficiencies of these vitamins are relatively rare. Lack of trace elements, in particular
`zinc and selenium, occurs in patients with SBS and results in epithelial and mesenchymal
`dysfunction as well as immunodeficiency.6
`About 60% of SBS patients show hyperoxaluria with an increased risk of calcium-
`oxalate kidney stones as a result of increased oxalate absorption. This is a consequence
`of decreased intraluminal availability of calcium caused by binding of calcium to
`malabsorbed fatty acids.
`In healthy subjects calcium binds to oxalate to form
`unabsorbable calcium oxalate. In SBS patients, lack of free intraluminal calcium allows
`increased absorption of unbound oxalate.
`Calcium, magnesium and iron as well as folic acid are predominantly absorbed by the
`duodenum and deficiencies are a typical consequence of expanded proximal small
`bowel resections. Malabsorption of calcium may be particularly severe because
`absorption is further hampered by binding of calcium to malabsorbed fatty acids and by
`vitamin D deficiency. In contrast, the specific uptake mechanisms allowing absorption of
`vitamin B12 and of bile acids are limited to the terminal ileum. The loss of the ileum
`leads to a vitamin B12 deficiency and to spill-over of unabsorbed bile acids into the
`colon, which causes cholerheic diarrhoea. After resections of more than 60–100 cm of
`the ileum the loss of bile acids usually exceeds synthesis and the bile acid pool
`decreases. This increases the risk of cholesterol gall stones and causes or deteriorates
`steatorrhoea. On the other hand,
`increased colonic bile salt levels may solubilise
`unconjugated bilirubin, prevent calcium complexing, and promote its absorption and
`enterohepatic cycling, thus explaining the 3–10 fold increase in bilirubin levels observed
`in the bile of patients with ileal Crohn’s disease.7,8 Putatively, increased bilirubin levels in
`the bile following extensive distal small bowel resections may lead to the formation of
`pigment gallstones.
`In patients with Crohn’s disease affecting the terminal
`ileum
`additional functional losses due to chronic inflammation may further impair vitamin B12
`and bile acid absorption even if small bowel resection is limited.
`In addition, the duodenum plays an important role in the stimulation of digestive
`responses, in particular of pancreatic enzyme output. Thus, the loss of the duodenum
`may lead to maldigestion of nutrients which further impairs absorption.
`In healthy humans, exposure of the terminal ileum to nutrients induces inhibition of
`digestive secretory and motor functions (the so-called ileal brake).9–11 The lack of the ‘ileal
`brake’ following ileal resections causes gastric hypersecretion and accelerated small bowel
`transit. Both mechanisms may substantially deteriorate diarrhoea in patients with SBS.
`
`% Losses of the duodenum or the terminal ileum impair absorption much more than loss
`of other parts of the small bowel because specific absorptive and regulatory functions
`of these intestinal sites cannot be replaced by other parts of the small bowel.
`% Absorption of major food components varies in SBS. Fat malabsorption is usually
`particularly severe, not compensated by colonic mechanisms and associated with
`deficiencies of the fat soluble vitamins A, D, E and K.
`% Deficiencies of the water soluble vitamins B1, B2, B6 and C are relatively rare.
`% By contrast, hyperoxaluria with an increased risk of nephrolithiasis is observed in 60%
`of patients.
`% Calcium, magnesium and iron as well as folic acid deficiencies are a typical
`consequence of expanded proximal small bowel resections.
`% The loss of the ileum leads to vitamin B12 deficiency and to spill-over of
`unabsorbed bile acids into the colon, which causes cholerheic diarrhoea.
`
`Page 4
`
`

`
`Management of the short bowel syndrome after extensive small bowel resection 981
`
`In addition, such patients have an increased risk of gallstone formation
`(cholesterol and pigment stones).
`% In patients with Crohn’s disease functional losses due to chronic inflammation may
`further impair absorptive functions even if small bowel resection is limited.
`
`Adaptation
`
`Adaptation of the remaining intestine is mainly stimulated by exposure of the residual
`mucosa to macronutrients and occurs on several levels.12,13 In particular, the remaining
`bowel increases in length and diameter and there is hyperplasia of small
`intestinal
`mucosa with increased number and size of crypts and villi. In addition, individual cells
`can increase certain absorptive functions (e.g. for sodium and calcium), though not
`all.14,15 The overall result of these adaptive mechanisms is an increased mucosal surface,
`and an increased absorptive capacity per surface. In addition,
`intestinal motility is
`slowed which increases contact time of nutrients with the mucosa and thereby
`improves absorption. Important neurohormonal mediators which are released by the
`terminal ileum and which at least partly also have trophic effects are glucagon-like
`peptide 1 and 2 (GLP-1 and GLP-2), peptide YY (PYY) and neurotensin.16–22 However,
`this important mechanism is only operative if the ileocecal region is preserved, which at
`least partially explains why these patients fare so much better. In combination, adaptive
`responses increase absorptive capacity by several hundred percent and are the basis of
`long-term management. They develop over 1–2 years following onset of SBS or even
`beyond, as is suggested by a longitudinal study on calcium absorption.23
`Animal studies and preliminary uncontrolled studies in SBS patients suggested that
`growth hormones might accelerate and improve the adaptation process.24–28 However,
`controlled clinical trials did not confirm this fully.29–31 Moreover, in patients with active
`Crohn’s disease a disturbed or delayed adaptation process has to be expected. This is
`also true for patients with radiation enteritis, carcinoma or chronic intestinal pseudo-
`obstruction.
`
`% Adaptation of the remaining intestine requires exposure to macronutrients.
`Adaptive responses develop over 1–2 years following intestinal resection and
`increase absorptive capacity by several hundred percent as a result of increased
`mucosal surface, increased absorptive capacity per surface and slowed intestinal
`motility.
`% Important neurohormonal mediators involved are glucagon-like peptide 1 and 2
`(GLP-1 and GLP-2), peptide YY (PYY) and neurotensin.
`
`THERAPY
`
`In concert with the adaptation process, the treatment of the SBS involves three phases.
`The immediate acute phase lasts less than 4 weeks and serves to stabilise the patient.
`The subsequent year should be used to induce maximal adaptation by gradually
`increasing nutrient exposure. When maximal stimulation of nutrient absorption has
`been achieved, permanent maintenance nutrition treatment should be defined
`
`Page 5
`
`

`
`982 J. Keller, H. Panter and P. Layer
`
`individually, dependent on extent and quality of nutritive deficits. In patients with SBS
`due to Crohn’s disease, effective therapy of the underlying disease is essential.
`The main therapeutic goals in SBS patients are adequate supply of
`† nutrients
`† water and electrolytes
`† vitamins and trace elements and
`† avoidance of acid–base dysbalance.
`
`Because of the low incidence and heterogeneity of the disease, randomised placebo
`controlled trials have hardly been performed in patients with short bowel syndrome.
`Instead, most recommendations are based on open clinical trials, several reflect
`experts’ opinions only.
`
`Acute phase
`
`Therapeutic options are depicted as an algorithm in Figure 1. The dominant clinical
`problem in the acute phase is massive diarrhoea32 which is not only due to insufficient
`nutrient absorption but may also evolve or be aggravated by several other
`pathomechanisms, i.e. massive gastric hypersecretion, malabsorption of bile acids and
`the loss of the ‘ileal brake’ mechanism. Consequently, during the acute phase, patients
`receive parenteral nutritional support and gastric acid secretion inhibitors (Table 1). If
`necessary the somatostatin-analogue octreotide can be applied in order to reduce the
`intraluminal fluid load.33
`
`% The dominant clinical problem in the acute phase is massive diarrhoea which is
`treated by parenteral nutritional support, gastric acid secretion inhibitors and, in
`severe cases, the somatostatin-analogue octreotide.
`
`Acute phase
`1./2. Postoperative day
`
`2./3. Postoperative day
`Adaptation phase
`4./5. Postoperative day
`
`Later on
`
`Maintenance phase
`
`Table 1. Dietary therapy in short bowel syndrome.
`
`Infusion therapy using Ringer, glucose and amino acid solutions, substitution
`of water soluble vitamins and trace elements
`Start of total parenteral nutrition
`
`Oral/enteral nutrition with gradually increasing nutrient loads: isoosmolar
`salt–glucose-solutions, tea, carbohydrate solutions, medium chain trigly-
`cerides, amino acids
`Predominantly long chain triglycerides, free fatty acids, small amounts of
`medium chain triglycerides in patients with preserved colon, saccharose,
`maltose, glutamine, pectin, substitution of vitamins and minerals as needed,
`in particular calcium
`
`Oral nutrition in stable patients: many small meals, high fat diet, small
`amounts of medium chain triglycerides in patients with preserved colon,
`fluids can usually be taken with meals, substitution of vitamins and minerals
`as needed, in particular calcium
`Avoidance of nutrients rich in oxalate if distal small intestinal resection
`
`Page 6
`
`

`
`Management of the short bowel syndrome after extensive small bowel resection 983
`
`Adaptation phase
`
`Depending on the condition of the patient, first attempts to start oral or enteral
`nutrition are made early, e.g. around the 4th or 5th postoperative day (Table 1). It can
`be difficult to determine the adequate initial quantities of oral or enteral nutrition. If the
`volume or osmotic load exceeds absorptive capacity, the patients may respond with
`diarrhoea, exsiccosis and metabolic disturbances, Thus, oral
`intake must be very
`gradually increased to 30–40 kcal/kg/d (with respect to ideal body weight) by frequent
`small solid meals. It is debated whether separated intake of solids and liquids helps to
`reduce diarrhoea.34 Anyway, liquids should not be sweetened with disaccharides in
`order to prevent osmotic diarrhoea. Tap water lacks electrolytes and should be
`avoided, too. Instead, isoosmolar saline–glucose-solutions are usually of advantage.35
`Because there is a tendency for metabolic acidosis, bicarbonate should be added during
`the first months of the adaptation phase. Slowing of intestinal motility with loperamide
`or codein in addition to suppression of gastric acid output may be helpful in controlling
`diarrhoea.
`If oral nutrition is not sufficient to ensure adequate energy supply and/or not
`tolerated by the patient, continuous enteral nutrition (EN) can be used in the adaptive
`phase. As an alternative to permanent nasogastric feeding pump devices, patients may
`place the tube necessary for enteral nutrition themselves for each night, or a
`percutaneous endoscopic gastrostomy can be performed. Continuous infusion is
`started at a very low rate and progressively increased over a 2–3 week period to the
`target rate. If EN is the only source of energy, up to 45–60 kcal/kg/d may be required
`eventually to achieve an uptake of 30–40 kcal/kg/d because a malabsorption rate of 30%
`has to be taken into account. Although continuous enteral infusion of nutrient solution
`is superior to bolus administration, aggravation of diarrhoea may still be a problem of
`enteral nutrition. However, in a recent study, Levy et al have used continuous EN as
`initial adaptive phase nutrition starting 2 weeks after operation in patients with both
`more or less than 80 cm of intestine left. They observed that stool volume gradually
`decreased with time in the patients with more than 80 cm of remaining intestine, and at
`least did not increase in those patients with a very short bowel.36
`The amount of carbohydrates excreted with faeces correlates directly with stool
`volume and, thus, with diarrhoea. Rice starch is absorbed best compared with other
`carbohydrates37,38 and is particularly suitable for dietary therapy. On the other hand,
`soluble dietary fibres which are degraded to short chain fatty acids by the colonic flora
`can contribute considerably to energy supply in patients with intact colon (up to 500–
`1000 kcal/d).39–41 Moreover, these patients may profit from the addition of medium
`chain triglycerides.42
`Glutamine has been shown to be a major source of energy for the enterocyte.
`Accordingly, experimental data in animals and uncontrolled studies in SBS patients
`suggested that enteral or parenteral substitution of glutamine might accelerate and
`ameliorate adaptation processes.43–45 However, subsequent randomised controlled
`trials could not confirm these positive effects.46,47 If glutamine was combined with
`growth hormone, even negative effects such as peripheral oedema occurred.48–50
`Positive effects were not sustained beyond the treatment period.51 Consequently,
`these therapeutic options cannot be recommended without restrictions. On the other
`hand, a recent study demonstrated an increase in intestinal nutrient absorption and
`body weight in patients requiring home parenteral nutrition and receiving low doses of
`growth hormone only. 52
`
`Page 7
`
`

`
`984 J. Keller, H. Panter and P. Layer
`
`Small bowel length > 60-80 cm
`Ileocecal region preserved
`Colon (partially) preserved
`
`yes
`
`no
`
`• TPN during acute phase only
`• isotonic salt-glucose-solutions
`• control and compensation of electrolyte
`and water deficiencies
`• H2-blocker / PPI for the first 6 months
`• Antidiarrheal drugs
`• Adequate nutrient supply
`• MCT
`• Avoidance of oxalate in diet
`• 800-1200 mg calcium p.o.
`
`• longer lasting partial or total parenteral
`nutrition
`• isotonic salt-glucose-solutions
`• control and compensation of electrolyte
`and water deficiencies
`• H2-blocker / PPI for the first 6 months
`• Antidiarrheal drugs
`• 800-1200 mg calcium p.o.
`• intensive training for home parenteral
`nutrition
`
`Reduction and termination of
`parenteral nutrition (if possible)
`
`tolerated
`
`not tolerated
`
`• Continuation of oral nutrition and above
`mentioned measures
`• Control and substitution of vitamin and trace
`element deficiencies
`• Annual measurements of bone density
`
`• Continuation of (partial) parenteral
`nutrition and above mentioned measures
`• Control and substitution of vitamin and
`trace element deficiencies
`• Annual measurements of bone density
`
`In case of complications:
`Hepatobiliary system : cholestasis, steatosis, liver failure → oral nutrition, reduce
`dextrose and fat content of TPN; cholelithiasis → cholecystectomy
`
`Bones : check calcium and vitamin D, if necessary substitute bisphosphonate i.v.
`Infections : improve handling of catheter
`Catheter occlusion : try to flush, adaptation of TPN solution, anticoagulation
`
`Improvement
`
`No improvement /
`deterioration
`
`Continuation of above mentioned measures
`
`Small bowel (and liver) transplantation
`
`Figure 1. Therapeutic options and algorithm in short bowel syndrome.
`
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`
`

`
`Management of the short bowel syndrome after extensive small bowel resection 985
`
`Moreover, GLP-2 has been demonstrated to have antisecretory, transit modulating
`and intestinotrophic effects. As illustrated in preliminary studies, GLP-2 may prove to
`be important in the attempt to optimise remnant intestinal function in the future.53,54
`However, controlled clinical trials are lacking, so far.
`
`% First attempts to start oral or enteral nutrition should be made around the 4th or
`5th postoperative day.
`% Oral
`intake must be very gradually increased. Frequent small solid meals are
`advisable. If this is not sufficient to ensure adequate energy supply or not tolerated,
`continuous enteral nutrition can be used.
`% Growth hormone (and GLP-2) may improve the adaptive process.
`
`Maintenance phase
`
`As mentioned above, most patients with a manifest SBS will have to cope with an
`average malabsorption of 30% of nutrients ingested. This means that for a target
`absorption rate of 30–40 kcal/kg/d (ideal body weight), about 45–60 kcal/kg/d must be
`ingested, preferentially distributed over many small meals and including adequate and
`regular supplementation of vitamins, minerals and trace elements (Table 2).
`In
`particular, if no distal ileum is left, vitamin B12 must be supplemented parenterally. As
`explained above, calcium should be given generously by mouth (800–1200 mg/d) not
`only to substitute for decreased calcium absorption but also in order to prevent
`increased absorption of oxalate resulting in nephrolithiasis. Oral substitution of
`its laxative effect.55 Modern concepts of
`magnesium may be difficult because of
`nutrition of patients with SBS use high fat diets during the maintenance phase which are
`superior in energy supply to the traditional low fat approach. To achieve this pivotal
`goal, the aggravation of steatorrhoea resulting from increased fat intake may have to be
`accepted.56,57 Moreover, small amounts of medium chain triglycerides are absorbed by
`the colon and may be included in the diet as an additional energy source in patients with
`the colon in continuity.58 On the other hand, excessive intake of medium chain
`triglycerides may induce nausea, vomiting and ketosis.59
`Bacterial overgrowth may lead to an unexpected increase in nutrient requirements
`or decrease in body weight. It is particularly likely if the orocecal valve has been
`
`Table 2. Substitution of vitamins and trace elements in short bowel syndrome (modified according to
`Buchman et al59).
`
`Vitamin A
`Vitamin B12
`Vitamin C
`Vitamin D
`Vitamin E
`Vitamin K
`Selen
`Zink
`
`10,000–50,000 U/d if liver function is normal
`300 mg s.c. per month following resection of terminal ileum
`200–500 mg/d
`1600 U/d
`30 IU/d
`10 mg/week
`60–100 mg/d
`220–440 mg/d
`
`Doses given above are for orientation, only. The exact individual requirements must be evaluated and
`doses adjusted according to regularly performed appropriate laboratory measurements.
`
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`

`
`986 J. Keller, H. Panter and P. Layer
`
`Table 3. Drug therapy in short bowel syndrome.
`
`Drug
`
`Loperamide
`H2-antagonists
`Ranitidine
`Famotidine
`Omeprazole
`Octreotide
`Cholestyramine
`Pancreatin
`Metronidazole
`
`Oral application if not stated otherwise.
`
`Recommended dose per day
`
`4 –16 mg
`
`300 – 600 mg
`40 – 80 mg
`20 – 40 mg
`2–3!50–100 mg subcutaneously
`4–16 g
`25,000 – 40,000 U per meal
`800 –1200 mg
`
`resected. In many patients with bacterial overgrowth repetitive or even continuous use
`of antibiotics is necessary.60
`
`Drug therapy
`
`Absorption of nutrients as well as symptoms resulting from malabsorption can be
`improved by drugs acting on various levels. Therefore rational treatment approaches of
`SBS often include the combination of drugs which influence gastrointestinal secretory
`and motor functions (Table 3). Loperamide and codeine act on opiate receptors and
`slow intestinal transit.61 H2-receptor blockers and proton pump inhibitors decrease
`gastric acid hypersecretion.62,63 Colestyramine is effective in cholerheic diarrhoea
`through the binding of bile acids. It may, however, deteriorate steatorrhoea particularly
`in patients with extensive ileal resections and should be used cautiously. On the other
`hand, in single patients, substitution of bile acids appears to increase water and nutrient
`absorption.64 Somatostatin and its analogue octreotide strongly inhibit not only gastric
`acid secretion but all digestive secretions as well as gastrointestinal transit and
`therefore strongly reduce intraluminal fluid load.65–67 They can be especially helpful in a
`problematic subgroup of patients with very little remaining small bowel with or without
`preservation of the colon. However, octreotide is expensive and, moreover, there is
`evidence that tachyphylaxis develops within weeks. Thus, it may rather be of value in
`critical stages during the adaptation phase than for permanent treatment.68 The
`supplementation of pancreatic enzymes with meals may compensate for postcibal
`asynchrony,
`i.e. disturbed coordination of gastrointestinal transit of nutrients and
`pancreatic enzyme secretion and, thus, improve digestion.69
`Broad spectrum antibiotics are of value for the control of bacterial overgrowth.
`They should be used rigorously, particularly in patients receiving parenteral nutrition in
`order to reduce the risk of chronic liver failure.70
`
`% Because of an average malabsorption rate of 30% most SBS patients need
`hyperalimentation including adequate and regular supplementation of vitamins,
`minerals and trace elements.
`% To achieve adequate energy supply, diets need to contain sufficient amounts of fat.
`Patients with preserved colon may profit from the addition of low amounts of
`medium chain triglycerides.
`
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`
`Management of the short bowel syndrome after extensive small bowel resection 987
`
`% Calcium should be given generously by mouth not only to substitute for
`malabsorption but also to avoid hyperoxaluria and nephrolithiasis.
`% Absorption and symptoms can be improved by the following drugs: Loperamide and
`codeine can be used to slow intestinal transit. H2-receptor blockers and proton
`pump inhibitors decrease gastric acid hypersecretion. Colestyramine reduces
`cholerheic diarrhea but may deteriorate steatorrhea. In single patients, substitution
`of bile acids appears to increase water and nutrient absorption. Pancreatin
`preparations may improve digestion. Somatostatin analogues strongly reduce the
`intraluminal fluid load and can be helpful in patients with very little remaining bowel.
`Antibiotics are needed in patients with small bowel bacterial overgrowth.
`
`Maintenance parenteral nutrition
`
`According to the data of a recent study, the combined use of a specific diet, growth
`hormone and glutamine may enable totally oral nutrition even in patients with less than
`50 cm of small bowel left.71,72 However, despite all efforts to optimise modes of enteral
`nutrition and drug therapy, there is a substantial group of patients left who cannot cope
`with oral or enteral nutrition alone, but require parenteral nutrition at certain intervals
`or continuously.73 These patients require—dependent on their occupation—30–
`40 kcal/kg/d; 32 kcal/kg/d are recommended for total parenteral nutrition. In addition,
`electrolytes, minerals, vitamins and trace elements must be supplemented.
`Continuous home parenteral nutrition demands strict selection and intensive
`training of the patient, together with systematically organised, competent nursing
`support, e.g. patients must be willing and able to cooperate and to learn, understand
`and practice the principles of asepsis. Follow-up series suggest that with adequate
`support, complications such as infection, dislocation, obstruction, thrombosis, etc. can
`be limited to an acceptable range.74–76 Even with continuous parenteral nutrition, care
`has to be taken to regularly expose the remaining intestinal mucosa to nutrients in
`order to maintain remaining absorptive, secretory and motor functions and to avoid
`parenteral nutrition-associated cholestasis.
`
`% A substantial group of patients requires parenteral nutrition at certain intervals or
`continuously. In addition, electrolytes, minerals, vitamins and trace elements must
`be supplemented.
`% Continuous home parenteral nutrition demands strict selection and intensive
`training of the patient, together with systematically organised, competent nursing
`support.
`% Even patients receiving total parenteral nutrition need regular exposition of the
`remaining intestinal mucosa to nutrients in order to avoid complications.
`
`Surgical therapy
`
`The primary goal of conventional surgical interventions is to increase nutrient and
`water absorption by slowing gastrointestinal transit and/or increasing the absorptive
`surface. The following surgical procedures were performed with limited success in
`small groups of patients, so far: interposition of antiperistaltic small bowel segment or
`of colon, construction of