Short bowel syndrome

short bowel syndrome etiology,clinical features,management,prognosis

1. Recent advances- Short Bowel Syndrome(SBS) by G.P.Chakravarthy Moderator – Dr.SaiKrishna

2. Defined as a type of intestinal failure which results from surgical resection,congenital defect or disease – associated loss of absorption and is characterised by the inability to maintain protein energy,fluid,electrolyte or micronutrient balances when on a conventionally accepted normal diet. Definition

3. Due to functional or anatomical loss of extensive segments of small intestine so that absorptive capacity is severely compromised Extensive segments - 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 SBS. Intro

4. Etiology Adult Pediatric Mesenteric ischemia - thrombosis and embolism of superior mesenteric vessels Crohn’s disease Radiation enteritis Neoplastic Motility disorders Trauma Necrotizing enterocolitis Multilevel small-bowel atresia Midgut volvulus with ischemic bowel infarction

5. Manifestations : Malabsorption Diarrhea Steatorrhea Fluid and electrolyte disturbances Cholelithiasis Bone disease Gastric acid hypersecretion Liver Intro

6. Nutrient,electrolyte,fluid absorption capacity are proportional to the length of residual small intestine Functional impairment depends on : Length of intestine Segments of intact bowel The absorptive quality of remnant bowel Inter-individual variability in adaptation Pathophysiology

7. Jejunal Resection : Digestive enzymes – greatest proportion of digestive enzymes are conc. i n villi of jejunum- initial reduction in absorption of nutrients – until adaptation. Loss of physiological GI feedback mechanisms – results in rapid gastric emptying If <100 cm remains – net secretory response to the food. Pathophysiology

8. Ileal resection : Normally most of 8-9 litres of secretions are reabsorbed by ileum -if <100cm of ileum left insitu – net secretory response to food Site of absorption of B12 and bile salts – results in bile salt & fat malabsorption and anemia Feedback mechanisms (peptide YY,GLP1) which detect malabsorption are altered Pathophysiology

9. Loss of ileocecal valve : Small bowel dilatation and slower motility Increased risk of bacterial overgrowth Competetion for nutrients,bacterial translocation & endotoxemia,lactic acidosis Pathophysiology

10. “ Colon in continuity ” : In adapation process colon adapts the role of digestive organ It slows the transit time and stimulate intestinal adaptation – compensate for lack of small bowel – reabsorbs water,electrolytes &SFA Flora of colon ferment carbs to SFA – when absorbes provides 500kcal/day Pathophysiology

11. The physiologic changes and adaptation of patients with short-bowel syndrome can be viewed in two phases . Acute phase Adaptation phase Adaptation

12. Acute phase : The acute phase occurs 24-48hrs after massive bowel resection. 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. Adaptation

13. Adaptation phase : The adaptation phase generally begins 2-4 days after bowel resection and may last up to 12-18 months. During this phase , up to 90% of the bowel adaptation may occur. Villous hyperplasia Increased crypt depth Intestinal dilatation occur. Early low volume continuous feedings may reduce the duration of TPN. Adaptation

14. EARLY 1.Diarrhea and electrolyte disturbances : Electrolytes are secreted in jejunum and ileum – loss of these segments – net electrolyte losses Even if sr.magnesium and potassium levels are maintained , body electrolytes are reduced – to diagnose - check urinary electrolyte levels Complications

15. 2.Gastric hypersecretion : Loss of negative feedback – may persist upto 6months – lead to peptic ulcers,oesophagitis . Complications

16. LATE : Metabolic complications TPN related complications Bacterial overgrowth Micronutrient deficiencies Complications

17. Strategies : Management REPLACEMENT : Fluid,nutrients,electrolytes Increase absorption: ORS Antimotility agents A daptation Teduglutide Nontransplant surgical treatment

18. Fluid and electrolyte management : Begin TPN within first 24 hrs (25-35kcal/kg/day) Measurement and replacement of fluid losses and electrolytes every 2hrs Blood glu every 4hrs If Remaining jejunum 75 cms – likely longterm TPN 100cm – tpn + fluid supplements 200cm – ors will be necessary Early goals

19. Introduction of enteral nutrition : Initially low rate continuously (enteral tube)– trickle feeds – 5% of daily requirement – advanced every 3-7days Diet should be of high fat and protein – 40% of requirent – to minimize osmotic diarrheal complications Management

20. Pharmacological adjuncts : Antimotility agents – loperamide,clonidine,codeine Decrease secretions – octreotide decreases panceartic secretions & increases small intestine transit time Cholestyramine – in steatorrhea – secondary to bile acid malabsorption following ileal resection PPI and H2 receptor blockers reduce acid secretion Management

21. Methods to promote adaptation Glutamine , growth harmones , diets high in carbs stimulate adaptation process GLP-2 analogue ( teduglutide ) is under studies. Management

22. 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 Prevention of complications

23. Aim is to preserve the intestinal remnant length Avoid resection much as possible Surgical therapy

24. Patients with marginal remnant, 60 -120cm They have rapid transit Reversing 10 – 15 cm segment yielded good results Segment of colon interposed in either antiperistaltic direction Other options Creation of artificial valves – not successful Retrograde intestinal pacing with electrodes Methods to slow intestinal transit

25. Longitudinal intestinal lengthening and tailoring(LILT) – Bianchi procedure Allocate terminal blood vessels anatomically to the either side of the bowel wall This is mainly used in children particularly- significantly dilated residual intestine,dismotility,bacterial over growth Methods to increase intestinal area

26. Bianchi procedure

27. Serial transverse enteroplasty (STEP):

28. Serial transverse enteroplasty (STEP ): Repeated applications of linear stapling device from opposite directions in zig zag fashion Requires diameter at least 4 cm Recurrent dilatation can managed in similar fashion 80% of patients improve clinically STEP is preferable than Bianchi procedure Methods to increase intestinal area

29. Indicated in Patients with life threatening complications due to intestinal failure Those destined for lifelong TPN Thrombosis of 2 or more central veins 2 or more episodes of cathter related sepsis Singe episode of line related fungemia septic shock, ARDS Frequent episodes of severe dehydration despite IV supplementation Intestinal transplantation

30. 2types Isolated intestine transplantation Combined intestine + liver tansplantation Combined transplant is done in patients with end stage liver disease Intestinal transplantation

31. Complications : Anastamotic leaks Spontaneous bowel perf Hepaticartey thrombosis Infection REJECTION – acute rejection can be diagnosed by loss of villi and immune cell infiltrate Intestinal transplantation

32. Survival rates are 90 % at 1yr 70 % at 3yrs for intestine only transplants 70% at 1 yr and 68% at 3 yrs for combined transplants Intestinal transplantation

33. Best thing to do in SBS is to prevent it by resecting the bowel as little as possible. Conclusion