Short bowel syndrome

Nuwan gunapalaTrainee in general surgery

Introduction Epidemiology Etiology Pathophysiology Clinical features Management Prognosis

Presentation overview

Short-bowel syndrome is a disorder clinically

defined by Malabsorption Diarrhea Steatorrhea Fluid and electrolyte disturbances Malnutrition

Due to functional or anatomical loss of extensive segments of small intestine so that absorptive capacity is severely compromised

Introduction

No defined length of remaining bowel is

identified although various literature mentioned controversial lengths.

Less than 200 cm of viable small bowel or loss of 50% or more of the small intestine places the patient at risk for developing short-bowel syndrome.

The average length of the adult human small intestine is approximately 600 cm and the range extends from 260 to 800 cm –

Weser E. Nutritional aspects of malabsorption: short gut adaptation. Clin Gastroenterol. May 1983;12(2):443-61. [Medline].

Extensive segment

Intestinal failure associated with the inability

to maintain protein, energy, fluid, electrolytes or micronutrient balances while on conventionally accepted normal diet.

Short bowel syndrome and intestinal failure: consensus definitions and overview.O'Keefe SJ1, Buchman AL, Fishbein TM, Jeejeebhoy KN, Jeppesen PB, Shaffer J.

Definition

Prevalence is not identified worldwide United Kingdom, the incidence of short-bowel

syndrome which requires home TPN was 2 patients per million population

United States, approximately 10,000-20,000 patients receive home-delivered TPN 

Prevalence in Spain 1.8 patients per 1 million population

Epidemiology

Depends on age groups In adults

Crohn’s disease Mesenteric ischemia - thrombosis and

embolism of superior mesenteric vessels Radiation enteritis Iatrogenic – jejuno ileal bypass, now abandoned Neoplastic Motility disorders Trauma

Etiology

Necrotizing enterocolitis Multilevel small-bowel atresia Midgut volvulus with ischemic bowel infarction

Pediatric and neonatal age groups

About 90% of digestion and absorption of

significant macronutrients and micronutrients are accomplished in the proximal 100-150 cm of the jejunum

Symptoms occurs due to Loss of intestinal absorptive capacity Rapid intestinal transit Gastric hypersecretion and inactivation of

digestive enzymes Loss of bile salts

Pathophysiology

Functional or anatomical loss of small bowel

surface area will reduce the absorption of intestinal contents leading to symptoms of SBS

Loss of small bowel reduce pancreatic and biliary secretion and increase gastric secretion lowering the PH in small intestine which further impairs the action of digestive hormones

Impaired absorption will accumulate osmotically

active particles in small bowel retaining more water results in diarrhea.

Loss of ileum will results in reduced absorption of fats leading to steatorrhoea (reduction of bile salts)

Role of ileocecal valve Increase transit time allowing more absorption Prevent colonization of small bowel from large bowel

which will aggravate the diarrhea

Premorbid length of small bowel The segment of intestine that is lost The age of the patient at the time of bowel

loss The remaining length of small bowel and

colon, The presence or absence of the ileocecal

valve.

Other factors which affect outcome

Increases it water absorption capacity up to 5

times Colonized bacteria metabolize undigested

carbohydrates to short chain fatty acids which can be absorb to utilize as somatic fuel.

Increase absorption of oxalates and increase risk of urinary calculi formation

Increases colonization of small bowel in the absence of ileocecal valve

Place of colon

The physiologic changes and adaptation of

patients with short-bowel syndrome can be viewed in three phases.1. Acute phase2. Adaptation phase3. Maintenance phase

Sundaram A, Koutkia P, Apovian CM. Nutritional management of short bowel syndrome in adults. J Clin Gastroenterol. Mar 2002;34(3):207-20. 

Adaptations to live without small bowel

The acute phase occurs immediately after

massive bowel resection and may last up to 3-4 months.

It is associated with malnutrition and fluid and electrolyte loss through the GI tract.

Enteral feedings may also be initiated, but it should be relatively slow. Patients with less than 100 cm of small intestine will require TPN.

Sundaram A, Koutkia P, Apovian CM. Nutritional management of short bowel syndrome in adults. J Clin Gastroenterol. Mar 2002;34(3):207-20. 

Acute phase

The adaptation phase generally begins 2-4

days after bowel resection and may last up to 12-18 months.

During this second phase, up to 90% of the bowel adaptation may occur. Villous hyperplasia Increased crypt depth Intestinal dilatation occur.

Early continuous feedings with a high viscosity elemental diet may reduce the duration of TPN.

Adaptation phase

The absorptive capacity of the GI tract is at its

maximum. 

Some patients may still require TPN. In other patients, nutritional and metabolic

homeostasis can be achieved by small meals and supplemental nutritional support for life.

Maintenance phase

Weight loss, fatigue, malaise, and lethargy Vitamin A - night blindness and xerophthalmia Vitamin D - paresthesias and tetany Vitamin E - paresthesias, ataxic gait, and

retinopathy Vitamin K depletion - easy bruisability or

prolonged bleeding Vitamin B12, folic acid - Anemia Calcium and magnesium - paresthesias and

tetany Low zinc levels - anorexia and diarrhea

Clinical features

Temporal wasting Loss of digital muscle mass Peripheral edema Dry and flaky skin Prominent ridges in nail Lingual papillae are blunted or atrophic

Physical signs

Management of SBS is progressed through

several phases Management goals varies depending on

phases

Initial phase To stabilize critically ill patient Controlling sepsis Fluid and electrolyte balance Initiation of nutrtional support

Management

As patient is recovered from acute stage

primary goal of management is to maintain nutritional status To maximize the absorptive capacity Prevent complications of PN and short bowel

syndrome

Preserving the intestinal remnant Improve the function of remnant bowel Augmenting the intestinal length Intestinal transplantation

Management options

Goal is to return patients to as normal lifestyle

as possible with as little dependence on parenteral nutrition 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, antimotility and antisecretory agents, antibiotics and growth factors.

Medical rehabilitation

PN support in the early post operative period Provision of energy substrate, protein, fluid,

electrolytes, minerals, vitamins and micronutrients

25-30 kcal/kg per day 1 to 1.5 g of proteins per day

Maintain nutritional status

Should started as early as possible when ileus is settled

Help to maximize absorptive capacity and to reduce the complications related to PN

Patients with small bowel more than 180 cm will not require PN

Patients with small bowel more than 90 cm with colon require PN less than 1 year duration

Less than 60cm of small bowel might require permanent PN depending on colon length

Long-term survival and parenteral nutrition dependence in adult patients with the short bowel syndrome.Messing B1, Crenn P, Beau P, Boutron-Ruault MC, Rambaud JC, Matuchansky C.

Enteral feeding following surgery

Continuous enteral feeding may permit

greater absorption of nutrients than intermittent enteral feeding

Continuous enteral nutrition during the early adaptive stage of the short bowel syndrome. Levy E1, Frileux P, Sandrucci S, Ollivier JM, Masini JP, Cosnes J, Hannoun L, Parc R.

Hyposmolar diets are started initially to

reduce the intestinal fluid loss High protein high carbohydrate diets are

recommended for maximum absorption Providing nutrient as their simplest form

improves absorption Di and tri peptide sugars Medium chain tri glycerides

Addition of pectin increase transit time and reduce water loss

Maximize absorptive capacity

Early enteral nutrition Provision of long chain fatty acid and fiber Glutamin – trophic to the gut as well as act as

fuel for enterocytes Meal itself act as endocrine stimulation for

adaptation via various hormones and growth factors

Glutamine and the preservation of gut integrity. van der Hulst RR1, van Kreel BK, von Meyenfeldt MF, Brummer RJ, Arends JW, Deutz NE, Soeters PB.

Maximize adaptive capacity

To minimize diarrhoea and GI secretion Narcotics – codeine, diphenoxylate and

loperamide Diminished action over time

Progressive dosage Drug holidays

AGA technical review on short bowel syndrome and intestinal transplantation.AUBuchman AL, Scolapio J, Fryer J

Antimotility and antisecretory drugs

PPI and H2 receptor blockers reduce

gastrointestinal secretion Clonidine also reduce fluid loss (alpha 2

receptor agonist) Pre biotics and pro biotics also proven to

improve absorption

Potential benefits of pro- and prebiotics on intestinal mucosal immunity and intestinal barrier in short bowel syndrome.Stoidis CN1, Misiakos EP2, Patapis P2, Fotiadis CI2, Spyropoulos BG3.

GLP – 2

Increase intestinal absorption and adaptation Produce by enteroendocrine cells in small

intestine Shown to increase absorption and increase

villous height and crypt depth Still undergoing further studies

Short Bowel Patients Treated for Two Years with Glucagon-Like Peptide 2 (GLP-2): Compliance, Safety, and Effects on Quality of Life P. B. Jeppesen,1,* P. Lund,1 I. B. Gottschalck,1 H. B. Nielsen,2 J. J. Holst,3 J. Mortensen,4 S. S. Poulsen,3 B. Quistorff,3 and P. B. Mortensen1

Newer therapies

Complications of short bowel syndrome

Therapy related Diarrhea and steatorrhea Metabolic abnormalities Nutritional deficiencies Infectious complications Liver disease

Physiologic Cholelithaisis Nephrolithiasis Gastric hypersectretion Bacterial overgrowth

Prevent complications

Supplementation of vitamin D calcium and

magnesium Treat bacterial over growth in small bowel

which can cause metabolic acidosis Prevent catheter related sepsis PN related liver disease – multifactorial

Maximizing enteral calories Avoid over feeding Prevent specific nutrient deficiencies

Measures to prevent complications

Due to stasis, obstruction and absence of

iliocecal valve Reduce absorption by villous blunting Duodenal aspiration and culture is diagnostic Poorly absorbed antibiotics are preferable for

treatment Obstruction can be surgically corrected.

Small bowel bacterial overgrowth

Occur in 1/3rd of patients Due to increase bile stasis, and reduction of

bile salt absorption which leads to cholesterol stones

Early enteral feeding reduce the stasis and occurrence of bile stones

Intermittent CCK injections prevent stasis Consider prophylactic cholecystectomy when

laparotomy is being performed for other reasons.

Cholelithiasis

Increase risk in colon preserved patients Binding of non absorbed FFA with calcium

releases free oxalate which are soluble and absorbed in colon

Free oxalate bind with calcium and form stones in urine

To prevent Low oxalate diet Reduce intraluminal fat Oral calcium supplement Cholestyramine binds with oxalic acid in colon

Nephrolithiasis

Due to loss of inhibiting factors from the small

bowel Exacerbate malabsorption and diarrhea Causes peptic ulcer disease

Prevention by PPI and H2 receptor blockers, which continue up to 1 year postop

Gastric hyper secretion

Re operation surgery is required in half of the

patients Aim is to preserve the intestinal remnant

length Avoid resection much as possible Surgical options available

Intestinal tapering for dilated segments Strictureplasty Serosal patching Recruitment of isolated or bypassed bowel

segment

Surgical therapy

Half of the patients can maintain nutrition only

on enteral nutrition and doesn’t require surgery

But surgery should be consider if they are having following worsening malabsorption Increased requirement for parenteral nutrition Disabling symptoms related to malabsorption

Other half who is stable on TPN can undergo surgery in the aim of weaning off from PN

When to consider surgical treatment

Intestinal transplant should be consider in

patients who are having persisting and recurrent complications while totally depend on PN.

Many such patients will die prematurely

Intestinal remnant length Intestinal function Diameter of the intestinal remnant

Type of surgery depend on

Adults with remnant more than 120cm Initial conservative management But when dilatation occurs – due to

obstruction caused by adhesions of stricture at anastomotic site, surgery is done for adhesiolysis and strictureplasty

If necessary non functional short segment resection

Patients with marginal remnant, 60 -120cm They have rapid transit

Reversing 10 – 15 cm segment yielded good results

Other options Creation of artificial valves – not successful Retrograde intestinal pacing with electrodes

Surgical approach to short-bowel syndrome. Experience in a population of 160 patients. J S Thompson, A N Langnas, L W Pinch, S Kaufman, E M Quigley, and J A VanderhoofShould intestinal continuity be restored after massive intestinal resection? Nguyen BT1, Blatchford GJ, Thompson JS, Bragg LE.

Patients with short remnant length < 60 cm

with dilated bowel Goal is to preserve the functional length and

luminal diameter When the dilatation is progressive in the

absence of obstruction – adaptive dilation and attempted medical management are unsuccessful surgical intervention is indicated.

Longitudinal lengthening – Bianchi procedure Allocate terminal blood vessels anatomically to

the either side of the bowel wall Longitudinal transection of the bowel Anastomosis of two limbs

More than 100 cases reported Improvement is see in 80% of patients 20% complications – anastomotic leak,

ischemia Long term benefit in 50% of patients 10% underwent intestinal transplant Sudan, D., Thompson, J.S., Botha, J. et al, Comparisons of intestinal lengthening

procedures for patients with short bowel syndrome. Ann Surg. 2007;246:593–604.

Intestinal lengthening surgeries

Repeated applications of linear stapling device

from opposite directions in zig sag fashion Requires diameter at least 4 cm Recurrent dilatation can managed in similar

fashion 80% of patients improve clinically 5% undergone subsequent intestinal transplant STEP is preferable than Bianchi procedure

Kim, H., Fauza, D., Garza, J. et al, Serial transverse enteroplasty (STEP): a novel bowel lengthening procedure. J Pediatr Surg. 2003;38:425–429.Yannam, G., Sudan, D., Grant, W. et al, Intestinal lengthening in adults with short bowel syndrome. J Gastrointest Surg. 2010;14:1931–1936.

Serial transverse enteroplasty(STEP)

Indicate in patients with SBS with life

threatening complications Recurrent central venous catheter infections Progressive liver failure Progressive loss of central venous access

Intestinal transplant

2000 of transplants done in US by 2012 75% of patients are younger than 18 years 1 year graft survival is 89% in adults But children less than 1 year of age it is 69% Patients survival rates are similar at 1 and 5

year after transplant After one year of surgery 90 % of patients are

independent from PN

Intestine Transplantation in the United States, 1999–2008 Mazariegos, G. V.; Steffick, D. E.; Horslen, S.; Farmer, D.; Fryer, J.; Grant, D.; Langnas, A.; Magee, J. C. [less] 2010-04

Yang feng suffering SBS following resection of small bowel due to diverticulosis, 1st Chinese to survive successfully following Small bowel transplantation

Yang Feng, the first Chinese alive who received a small intestine

transplant holds his bride at the wedding

Medscape Current Management of the Short Bowel

SyndromeJon S. Thompson, MDcorrespondenceemail, Rebecca Weseman, RD, Fedja

A. Rochling, MB, BCh, David F. Mercer, MD, PhD

References