Dietetic Management of Short Bowel Syndrome Ali Singer Gastroenterology Specialist Dietitian...
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Transcript of Dietetic Management of Short Bowel Syndrome Ali Singer Gastroenterology Specialist Dietitian...
Dietetic Management of
Short Bowel Syndrome
Ali SingerGastroenterology Specialist Dietitian
Frenchay Hospital
Content
• Definition• Physiology• Management• Case Study
Definition
• The reduction of functioning gut mass to below the minimum necessary for the absorption of nutrients and/or water and electrolytes
Fleming & Remington,
1981
Variability in Intestinal Lengths• Small intestinal length at autopsy:
• 3-8.5m Bryant, 1924
• Shorter in women• SBS more common in women (67%)
• Small intestinal length at laparotomy:n mean (cm) range
(cm)Cook, 1974 6 421 320-521Backman, 1974 32 643 400-846Slater, 1991 38 500 302-782
Record of Intestinal Length
• Length removed often recorded
• Length remaining is more important:•Laparotomy•SB contrast studies (less accurate)
• Nutritional/fluid supplements needed if < 200cm SB
Causes of SBS
F istu la / obstruction
Ileus
C hem otherapy In fection
En te ritis
Sm all bowe l dysfunction
Acu te
Je junum -co lon Je junostom y
Short bow el G u t bypass
Irrad iation C rohns
En te ritis D ysm o tility
Sm all bowe l dysfunction
C hron ic
In testina l Failu re
Commonest causes: • Crohns • Superior mesenteric artery thrombosis• Irradiation
SBS: Anatomy• Mid-SB resection:
• Uncommon• Rarely problems
• Jejunocolic anastomosis:• Usually fluid balance maintained• Nutritional issues when SB <100cm
• Jejunostomy/high output enterocutaneous fistula:• Large stoma/fistula water and sodium losses• Dehydration• +/- nutritional problems
Types of Short Bowel
Pt Groups Jejunum
Ileum Colon Nutritional needs
Jejunum - ileum
Resected
Intact Intact Rarely need nutrition
Jejunum -colon
Resected
Intact Gradual undernutritionAdaption occurs<50cm may need TPN
Jejunostomy Intact Resected / Absent
Absent Fluid & electrolyte lossesNo adaption<100cm IV saline<75cm IV nutrition also
Normal GI PhysiologyJejunum
• Na+/H2O secretion 1st 100cm
• Leaky• Na+ absorption
• Small conc. gradient only• Dependent on H2O
movement• Coupled to gluc/AA
absorption
• Maximal Na+ absorption when [Na+] 120mmol/l
Ileum
Active Na+/H2O absorption
• Less leaky• Na+ absorption
• Large conc. gradient
• Not dependent on H2O movement
• Not coupled to gluc/AA absorption
• Increased by Aldosterone
Normal GI PhysiologyLiquid Vol secreted
(L)Vol absorbed(L)
External Food & drink 2
Salivary glands
Saliva 0.5-1
Stomach Gastric juice 2-3
Pancreas
Pancreatic juice 0.5-0.8
Liver Bile 0.5-0.9
Jejunum Passive proximal secretion & distal absorption
1-2 1-2
Ileum Active absorption 2-5, vit B12, bile salts
Colon Large capacity
External Faeces 400
Total 6.5-9.7 3-9
Gastrointestinal Motility
Jejunal-colon:NORMAL
Jejunostomy:FAST
Peptide YY and GLP-2 (glucagon-like peptide 2) are released when food passes the terminal ileum and caecum that act as ileal and colonic braking mechanisms; this is lost in jejunostomy
Physiological Consequences• Increased gastric emptying• Increased SB transit• Increased gastric secretions (first 2 wks)
• Resection of ileal & colonic braking mechanism
• Changes in GI hormones• Reduced peptide YY, glucagon like peptide 2• Increased gastrin
Critical Lengths
Critical SB length
Note
Jejunostomy
100cm More needed if diseased bowel
Jejunocolic anastomosis
~50cm Depends on amount of residual colon
Nutritional Support and Bowel Length
Jejunal length Jejunum-colon Jejunostomy
0 - 50 cm Parenteral nutrition Parenteral nutrition and saline +/- Mg
51 - 100cm Oral / Enteral nutrition
Parenteral nutrition and saline +/- Mg
85 - 100cm Parenteral saline
101 - 150cm None Oral / enteral nutrition and glucose / saline solution
151 - 200cm None Oral / enteral glucose / saline solution
• <200cm: restrict oral hypotonic fluids, sip glucose - saline supplement (100mmol/L Na, like jejunostomy fluid)
• <100cm: parenteral saline
• <50cm: parenteral nutrition and saline
GI Secretions
Jejunum – colon• Reabsorb unabsorbed fluid in colon
Jejunostomy• Salt and water loss from stoma• <100cm jejunum: losses > oral intake• Rapid sodium fluxes occur in jejunum
• If water/solutions of <90mmol/L sodium are drunk a net efflux of sodium into the bowel lumen occurs until 100mmol/L is reached
Absorptive Functions
B12 and fat malabsorption occur if >60-100cm terminal ileum resected
• Increased hepatic synthesis of bile salts cannot compensate; unabsorbed bile salts contribute to colonic secretion
Magnesium deficiency • Chelation of unabsorbed fatty acids
reduces absorption• Increased renal excretion; secondary
hypoaldosteronism
Hypomagnesaemia
R e du ced a bso rp tion
M a g ne s iu m ch e la tion w ith u n ab sorb ed fa tty ac ids
R e d uce d se cre tiona n d fu n ctio n P TH
D e c rea se d je ju n a lm a gn e siu m a bso rp tion
R e du ced m a nu fa ctu reo f 1 ,25 h yd ro xy-v itam in D
D ire c t inc re a se in re n a lm a gn e s ium losses
H yp oa ld ers te ro n ism d ueto hyp o na tre m ia
Clinical PictureWater Na Mg Nutrition
• Thirst• Low BP/ postural hypotension• Urea/ Creatinine/ Potassium• Daily body weight• Fluid balance/ stoma output• Low urine volume• Urine Na 1-2/7, then weekly, as OP 2-3 monthly• Depletion if urine Na <10mmol
Serum magnesiumHigh stoma outputSx in Mg < 0.6mmol/L
BMI <18.5kg/m2
Mid-arm muscle circumference <19cm: <22cm men
Adaptive Processes
• Hyperphagia; increased food intake
• Structural adaption:• increasing absorptive area
• Functional adaption;• slowing gastrointestinal transit (gastric emptying
and small bowel transit)• Occurs in jejunum-colon patients due to high
peptide YY and GLP-2, leads to increased jejunal absorption of macronutrients (glucose, water, Na, Ca) and overtime may no longer need TPN
Jejunum-Colon Pts
Post resection:• Parenteral fluids and nutrition (helps
surgical repair, ileus recovery and avoids deficiencies)
• 6/12 PPI• Multivitamin
Long term:• Undernutrition• Diarrhoea due to malabsorption• Vitamin/mineral deficiency
Undernutrition
• >50% of energy from diet malabsorbed• High energy foods, sip feeds +/- NG/PEG
feed; if fails TPN. Improves over time.• Long term TPN:
• Absorption of <33% oral energy intake• Absorption 30-60%, high energy requirements• Large volume stomal output / diarrhoea
• High carbohydrate, normal fat, low oxalate diet
• Topical sunflower oil for essential fatty acids
The Fat Dilemma
R e du cetra n s it t im es
R e d uce wa ter a ndso d ium ab so rp tion
R e d u ce b ac te ria lca rbo h yd ra te fe rm e n ta tion
In c rea sed s too l losses
B in d ca lc iuma n d m ag n es ium
R e na l s to n es
In c rea se o xa la tea b so rp tion
In c rea sedD la c tic a c id o s is
U n ab so rb e d lo n g ch a in fa tty ac id s in co lon
H ig h fa t d ie t
But high carbohydrate without fat is unpalatable and fat yields twice as much energy as carbohydrate; also a low fat diet risks essential fatty acid deficiency.
Deficiencies
Common:• B12 deficiency;
replace• Selenium deficiency;
replace• Magnesium
deficiency; replace if occurs
• Vitamins D, E, A, K and essential fatty acids; replace
Rare:• Potassium deficiency• Zinc deficiency; rare
unless large stool volumes
• Water and sodium; rare as absorbed well in colon, if occurs sips of glucose saline drink
Other complications
Diarrhoea• Limit food intake• Consider loperamide 2-8mg 30mins pre meals,
codeine 30-60mg 30mins pre meals• If >100cm terminal ileum resected cholestyramine
for bile salt malabsorption and reduced oxalate absorption
Confusion• Hypomagnesaemia, thiamine deficiency, lactic
acidosis (restrict mono / oligo saccharides) and hyperammonaemia (inadequate citrulline manufacture, Tx is arginine)
Drug absorption • warfarin, digoxin, thyroxine, loperamide and if <50cm jejunum
omeprazole may not be absorbed
Gallstones (calcium bilirubinate stones)• Bilary stasis. Therefore occurs in 45%, especially men• Tx IV amino acids, enteral feed, cholecystokinin injections,
NSAIDS, ursodeoxycholicacid, metronidazole, cholecystectomy
Renal stones (calcium oxalate stones/nephrocalcinosis/CRF)
• Occurs in 25% largely due to increased colonic absorption of oxalate
Social
Ca Oxalate Renal Stones
S ym pto m atic ren a l sto n es
L o w o xa la te d ie tA v o id d eh yd ra tion
In c rea se d ie ta ry C a
In c rea sed c o lo n ica b so rp tio n o f o xa la te
L o w fa t d ie tR e p la ce fa t w ith m e d ium
ch a in trig lyc e rid es
F a tm a lab so rp tion
O ra l cho le s tyra m ine
B ile sa lt ind u cedin c re ase d co lo n ic
p e rm e a b ility to o xa la te
R e d uce d b a cte ria ld e gra da tio n o f o xa la te
R e p la ce m e nt
P yrid ox in e o rth ia m in e d e ficie n cy
H yp o c itra tu ria
C a lc iu m ox a la tep re c ip ita tion in re n a l tra ct
N e p h ro ca lc in o s is+ /- re n a l fa ilu re
Jejunostomy Patient Issues• Salt and water depletion
• May be large volume of stomal output• Greater volume lost after food or fluids• GI secretion 4L/day, majority absorbed in jejunum
therefore more fluid losses via stoma if short jejunum• Jejunostomy fluid contains 100mmol/L Na,
15mmol/L K• If given hypotonic fluids 100mmol/L the mucosa
allows leaking of fluid and electrolytes into the lumen • Low sodium levels are NOT SIADH but sodium
depletion, this is resolved when urine Na 30mmol
• Hypokalemia• Rare, occurs when <50cm jejunum• Usually due to secondary hypoaldersteronism from Na
depletion
• Can be due to hypomagnesaemia causing potassium channel dysfunction and increased renal potassium secretion which responds to Mg not K supplements
• Hypomagnesaemia• B12 deficiency, confusion, drug absorption,
and gall stones• Nutritional
Jejunostomy Patient Issues
High Output Jejunostomy
• Exclude other causes of a high output
• Stage1: Establish stability
• Stage 2: Establish oral intake• Introduce enteral food/fluid/feed
• Stage 3: Rehabilitation•Stoma care, HPN training, social issues
• Stage 4: Long term care
Other Causes
• Intra-abdominal sepsis• Partial/intermittent bowel obstruction• Enteritis (clostridium, salmonella)• Recurrent disease in remaining bowel
(Crohn’s, irradiation)• Bacterial overgrowth• Suddenly stopping drugs (steroids, opiates)• Giving prokinetics (metoclopramide)• Coeliac• Hyperthyroidism
Stage 1: Establish Stability
• Severe dehydration & Na+ depletion•Keep patient NBM• IV normal saline (2-6L/day)
Treat the Cause
• Intraabdominal sepsis / abscess • Partial / intermittent bowel obstruction• Strictures; placement / muscle tunnel / adhesions /
crohns / ischaemic fibrosis / radiotherapy
• Enteritis; clostridium / salmonella / rota virus
• Recurrent disease; Crohns / irradiation
• Sudden stopping of drugs; steroids / opiates
• Drugs; prokinetics / metoclopramide / metformin / PPI / statin
• Diet; lactose intolerant / coeliac
Stage 2: Establish Oral Intake
• Restrict oral fluids to <500ml/day•Hypotonic (water, tea, coffee, squash,
alcohol)•Hypertonic (fruit juices, coca cola, sip
feeds)
• Drink a glucose-saline solution <500ml/day
Hypotonic Fluids
0 mmol Na+
High Output
100 mmol/L Na
Na+ and H2O
•Leaky
•Small conc. gradient only
•Dependent on H2O movement
Na 140 mmol/L
Unable to maintain Na gradient
jejunum
Electrolyte Mix
90 mmol Na+/L
Smaller volume
100mmol/L Na+
Na+ 140 mmol/L
Oral Rehydration Therapy
Na(mmol/L)
K (mmol/L)
Glucose(mmol/L)
Volume(ml)
WHO 90 20 111 1000
Electrolyte mix
90 0 111 1000
Dioralyte 60 20 90 200
Recipe: ORS
• 20g (6 teaspoons) glucose• 3.5g (1 level 5ml teaspoon) salt• 2.5g (1 heaped 2.5ml spoon) sodium
bicarbonate• 1L water • Add cordial, chill and drink through a
straw
Drug Therapy
Antisecretory:
• Omeprazole; decreases gastric acid secretion
• Ranitidine/cimetidine
• Octreotide; decreases
intestinal secretions
Antimotility:
• Loperamide upto 64mg PO o.d as decreased enterohepatic circulation
• Codeine• Lomotil
Vit/min supplements:
• B12, selenium, Mg2+, vit A, D, E, K
Parenteral Therapy
• 0.5–1L saline sc +/- 4mmol MgSO4
1-3/week
• 1L saline IV +/- 4-12 mmol MgSO4
> 3/ week
• IVN
Outcome Aims
• Clinical:• No thirst or signs of dehydration• Acceptable strength, energy and appearance
• Measures:• Gut loss <2L/day• Urine volume >800ml/day• Urinary Na+ >20 mmol/L• Normal serum Na+, Mg2+ and K+
• Body weight within 10% of normal
Stage 3: Rehabilitation
• Transfer to IF unit•Wound healing•Stoma care•HPN training
•1st patient 1978•Longest 27 years•Mean age 50.2 years (19.9 – 76.9)•~27 new patients per year per unit
•Social issues
Stage 4: Long-Term Care
• 3 monthly multidisciplinary clinics• IF unit•Shared care with local hospital
Outcome 1 year after starting HPN (467 patients)
74.2
15.1
8.1
0.9
1.1
0.6
0 20 40 60 80
C ontinuing on HP N
R eturned to oral
Died
In hospital
Withdrawn
R efused
% patients
100% mortalityP ancreatic malignancy (1)C O AD (1)MND (1)3.7% mortalityC rohn’s (188)
BANS 1996-2000
Mr J: background information•72 male UC (1961)
•Pan-protocolectomy (1962)
•Refashioned/Re-sited Ileostomy (1993)
•s/b Dr Kaskey, Renal Physician 2º renal impairment and kidney stones
•Referred from renal dietetic clinic (pt initially attempted to resist a referral!)
IssuesHigh output
ileostomy output (estimated up to
2.5L per day)
Renal impairment &
stone formation
Dehydration ( UO, urine Na)
Assessment: Concerns• Renal impairment:
* stage 4 CKD
• Poor seal on stoma bags
• Not leaving house when stoma active
Biochem Result
Na 134
K 3.5
Ur 20.0
Creat 233
eGFR* 25
Uric Acid 0.64
InterventionIntervention Rationale
1. Add salt to meals Increase Na intake (& serum Na)
2. Low fibre diet Insoluble fibre & residue through bowel
3. Restrict hypotonic fluids to 1L/d
Avoid drawing H20 (& Na) into the bowel
4. St Marks Fluid 1L/d Promote H20/ Na absorption
5. Loperamide 4m.g qds
Anti-motility agent
6. Forceval o.d
7. Check Mg and if deplete, convert Mg-glycerophosphate to Mg-oxide
On Mg supplements but levels not checkedMg oxide has less diarrhoeal effect
8. Refer to MXL Specialist f/u
Outcomes• Outcome measures
•Biochemistry:
Biochem 09.08.07 03.04.08
Na 134 142
K 3.5 4.7
Ur 20.0 12.9
Creat 233 202
eGFR 25 29
Uric Acid 0.64 0.41
Outcomes
• Reduction in stoma output from ~ 2.5 L to < 1L /d• Thickened output (watery porridge-like
consistency)
• Pt satisfaction• Practicalities in day-to-day management of
stoma
• Follow-up• Sole Dietetic f/u• Renal physician’s happy with progress
Thank-you
Any Questions?