Advances in the nontransplant medical and surgical management of intestinal failure

Improved tolerance for enteral nutrition after serial transverse enteroplasty (STEP) in infants and children with short bowel syndrome--a seven-year single-center experience

BACKGROUND

Serial transverse enteroplasty (STEP) was designed to lengthen and taper the small intestine in patients with short bowel syndrome (SBS) and dilated small bowel. We hypothesized that tolerance for enteral nutrition (EN) improves after STEP.

METHODS

Patients who underwent STEP between March 2004 and January 2011 were identified. Candidates for STEP had radiographic evidence of dilated small bowel and either failed to advance EN or demonstrated deterioration in tolerance for EN. Clinical and nutritional data were analyzed pre- and post-STEP. EN was defined as the percentage of calories administered enterally. Statistical analysis employed the signed rank test with significance assumed when p<0.05.

RESULTS

Twenty STEPs were performed at a median age of 13.7 months. Median pre-STEP bowel length was 30 cm with a median increase in bowel length of 42%. Five patients achieved enteral autonomy at a median of 6.5 months post-STEP. EN increased in 75%, while 25% exhibited unchanged or decreased EN post-STEP. In aggregate, median EN tolerance increased from 22% at one month pre-STEP to 61% at six months post-STEP (p=0.003).

CONCLUSIONS

The STEP is an effective adjunct in the treatment of patients with intestinal failure. While enteral autonomy is eventually possible in some patients, improved enteral tolerance can be achieved in a majority of cases.

Assessment and outcome of children with intestinal failure referred for intestinal transplantation

BACKGROUND & AIMS

Chronic intestinal failure (CIF) requires long term parenteral nutrition (PN) and, in some patients, intestinal transplantation (ITx). Indications and timing for ITx remain poorly defined. In the present study we aimed to analyze causes and outcome of children with CIF.

METHODS

118 consecutive patients referred to our institution were assessed by a multidisciplinary team and four different categories were defined retrospectively based on their clinical course: Group 1: patients with reversible intestinal failure; group 2: patients unsuitable for ITx, group 3: patients listed for ITx; group 4: patients stable under PN. Analysis involved comparison between groups for nutritional status, central venous catheter (CVC) related complications, liver disease, and outcome after transplantation by using non parametric tests, Mann-Whitney tests, Kruskal-Wallis, Wilcoxon signed rank tests and chi square distribution for percentage.

RESULTS

118 children (72 boys) with a median age of 15 months at referral (2 months-16 years) were assessed. Etiology of IF was short bowel syndrome [n = 47], intractable diarrhea of infancy [n = 37], total intestinal aganglionosis [n = 18], and chronic intestinal pseudoobstruction [n = 17]. Most patients (89.8%) were totally PN dependent, with 48 children (40.7%) on home-PN prior to admission. Nutritional status was poor with a median body weight at -1.5 z-score (ranges: -5 to +2.5) and median length at -2.0 z-score (ranges: -5.5 to +2.3). The mean number of CVC inserted per patient was 5.2 (range 1-20) and the mean number of CRS per patient was 5.5 (median: 5; range 0-12) Fifty-five patients (46.6%) had thrombosis of ≥2 main venous axis. At admission 34.7% of patients had elevated bilirubin (≥50 μmol/l), and 19.5% had platelets <100,000/ml, and 15% had both. Liver biopsy performed in 79 children was normal (n = 4), or showed F1 or F2 fibrosis (n = 29), bridging fibrosis F3 (n = 20), or cirrhosis (n = 26). Group 1 included 10 children finally weaned from PN (7-years survival: 100%). Group 2 included 12 children with severe liver disease and associated disorders unsuitable for transplantation (7-years survival: 16.6%). Group 3 included 66 patients (56%) who were listed for small bowel or liver-small bowel transplantation, 62/66 have been transplanted (7 years survival: 74.6%). Factors influencing outcome after liver-ITx were body weight (p < .004), length (p < .001), pre-Tx bilirubin plasma level (p < .001) and thrombosis (p < .01) for isolated ITx, Group 4 included 30 children (25.4%) with irreversible IF considered as potential candidates for isolated ITx. Four children were lost from follow up and 3 died within 2 years (survival 88.5%). Among potential candidates, the following parameters improved significantly during the first 12 months of follow up: Body weight (p.0001), length (p < .0001) and bilirubin (p < .0001).

CONCLUSIONS

many patients had a poor nutritional status with severe complications especially liver disease. PN related complications were the most relevant indication for ITx, but also a negative predictor for outcome. Early patient referral for Tx-assessment might help to identify and separate children with irreversible IF from children with transient IF or uncomplicated long-term PN, allowing to adapt a patient-based treatment strategy including or not ITx.

Non-transplant surgery for short bowel syndrome

The goal of any treatment programme for short bowel syndrome SBS is to achieve nutritional enteral autonomy. This must begin with conservation of as much bowel as possible from the time of first presentation. Frequent causes of the short bowel syndrome are intestinal atresia, necrotizing enterocolitis, midgut volvulus, extended intestinal aganglionosis, 'vanished gut' often associated with gastroschisis and occasionally catastrophic trauma. Atresia is more amenable to successful surgery than other causes, except when associated with gastroschisis. Intrinsic dysmotility has a poor prognosis. Intestinal lengthening procedures are only indicated if there is sufficient bowel dilatation. Extended intestinal aganglionosis is rarely amenable to any form of non-transplant surgery. Options available are to conserve bowel, close stomas early (use all available bowel to the maximum or even re-feed stoma effluent into the distal unused bowel), release adhesions causing obstruction, resect strictures, taper or excise localized dilatations and finally address dilated bowel with lengthening and tailoring operations. These procedures aim to improve effective peristalsis, thereby reducing bacterial overgrowth and improving nutrient contact with enteral mucosa to maximize absorption and intestinal adaptation. The Bianchi longitudinal splicing operation and the serial transverse enteroplasty operations have stood the test of time in providing considerable improvement in enteral nutritional autonomy in around 60% of cases. In SBS without dilatation attempts at 'mechanically' delaying transit (nipple valves, reversed bowel segments, colon interposition) have had inconsistent outcomes. Growing neomucosa and lengthening bowel by longitudinal stretch are still experimental.

Intestinal transplantation in infants with intestinal failure

Intestinal failure (IF) occurs when a person's functional intestinal mass is insufficient. Patients with IF are placed on parenteral nutrition (PN) while efforts are made to restore intestinal function through surgical or medical intervention. Patients who fail standard IF therapies may be candidates for intestinal transplantation (IT). Clinical outcomes for IT have improved to make this therapy the standard of care for patients who develop complications of PN. The timing of referral for IT is critical because accumulated complications of PN can render the patient ineligible for IT or can force the patient to await multiorgan transplantation.

Complications of enterocutaneous fistulas and their management

Complications related to enterocutaneous fistulas are common and include sepsis, malnutrition, and fluid or electrolyte abnormalities. Intestinal failure is one of the most feared complications of enterocutaneous fistula management and results in significant patient morbidity and mortality. The authors review emerging trends in the medical and surgical management of patients with intestinal failure.

[Small intestine, pancreas and islet cell transplantation]

The past decade has seen substantial improvements in patient and graft survival after intestinal transplantation. This improvement has been achieved by advances in donor and recipient selection, patient management, immunosuppression and surgical techniques. Intestinal transplantation is therefore considered a therapeutic option in the treatment of short bowel syndrome. Mile stones include the development of the calcineurin inhibitor Tacrolimus for immunosuppression as well as induction therapy using immune modulating substances like interleukin-2 receptor antagonists and antilymphocyte preparations. In addition to improvements in immunosuppression, antimicrobial prophylaxis and diagnosis of rejection, advances in surgical techniques have been crucial to achieving increased graft survival. Pancreas transplantation, generally with simultaneous kidney transplantation, is now available as a treatment option for patients with labile diabetes mellitus (usually type 1). Allogeneic islet transplantation was developed in the 1990s as a minimally invasive alternative to pancreas transplantation. Pancreatic islets are isolated enzymatically from the donor pancreas, in most cases infused into the portal vein and thus engrafted into the liver. Currently, technical and medical problems as well as high costs prevent the application of islet transplantation as a therapeutic option for a larger number of patients with diabetes mellitus.

Systematic review: medical and nutritional interventions for the management of intestinal failure and its resultant complications in children

BACKGROUND

Intestinal failure (IF) affects a growing number of children due to increasing numbers of preterm infants surviving intestinal resection for necrotising enterocolitis and improving surgical techniques for congenital gut anomalies. Parenteral nutrition (PN) is the mainstay of therapy; enteral nutrition may have trophic effects on the gut.

AIM

To review systematically evidence for the effectiveness of medical and nutritional interventions in the treatment of IF in children.

METHODS

Retrieval of data from studies of patients aged <18 years and receiving >28 days of PN. Outcome measures were improvement in intestinal function, intestinal adaptation, growth, prevention and treatment of IF-associated liver disease, and mortality. Cochrane Database (November 2009), MEDLINE (1950-November 2009) and CINAHL (1982-November 2009) electronic database searches were made using keyword and subject headings (MeSH): IF, Short Bowel Syndrome (SBS), PN and Child. The level of the evidence (EL) was assessed using SIGN (Scottish Intercollegiate Guidelines Network) methodology (http://www.sign.ac.uk).

RESULTS

From 1 607 620 hits, 720 abstracts were reviewed. Thirty-three original articles were included. No studies were of high methodological quality.

CONCLUSIONS

The evidence base for medical and nutritional interventions in paediatric IF is limited and of poor quality. In the absence of randomised-controlled trials, this evidence base can improve through case control and cohort research; and with better multiagency communication, the study of inter-centre differences is possible. Achievable short-term goals would include the study of: optimal ursodeoxycholic usage, novel intralipid formulations, cycled enteral antibiotics, enteral probiotics and new enteral feeding strategies.

Scaffold Characteristics for Functional Hollow Organ Regeneration

Many medical conditions require surgical reconstruction of hollow organs. Tissue engineering of organs and tissues is a promising new technique without harvest site morbidity. An ideal biomaterial should be biocompatible, support tissue formation and provide adequate structural support. It should degrade gradually and provide an environment allowing for cell-cell interaction, adhesion, proliferation, migration, and differentiation. Although tissue formation is feasible, functionality has never been demonstrated. Mainly the lack of proper innervation and vascularisation are hindering contractility and normal function. In this chapter we critically review the current state of engineering hollow organs with a special focus on innervation and vascularisation.