Nutrition Support for Intestinal Failure

A recent blog post by Kipp Ellsworth (The Pediatric Nutritionist) highlights a recent lecture by Conrad Cole that provides several useful points.  The post includes a link (embedded talk) to 76 slides. Here are a few:

  • Iodine deficiency: Dr. Cole “typically orders a TSH level every six months, also ordering a spot urine iodine if a significant TSH uptrend emerges.”
  • Lipids: “Dr. Cole reviewed evidence revealing the restriction of soy-based lipids to 0.5 gm/kg/day as nearly efficacious as the use of fish-oil infusion (Omegaven) in preventing PNALD.” Daily use of 0.5-1 gm/kg/day is less error-prone than using lipids 3-4 times/week.
  • Formula: “breastmilk constitutes the touchstone of enteral nutrition choices for the intestinal rehab patient, conferring a host of benefits beyond those associated with formula alone… the medium-chain triglyceride component of many oligomeric and monomeric formulas constitutes a therapeutically valuable source of nutrition, increasing the proportion of calories absorbed.”
  • Formula for toddlers: “Dr. Cole continues transitioning his patients to oligomeric and monomeric formulas such as Elecare Junior, Pediasure Peptide, and Peptamen Junior upon reaching toddlerhood.”
  • Fiber: “Dr. Cole recommended the use of a sc-FOS product such as NutraFloraas optimal for the short bowel syndrome population.  Dr. Cole initially doses soluble fiber at 1 gm/100 mL of formula and advances as tolerated to a maximum of 2 gm/100 mL formula.  He typically does not use supplemental fiber to control ostomy output in patients without a colon in continuity”
  • Enteral fish oil: “Dr. Cole remains unconvinced of the therapeutic value of enteral fish oil supplementation pending further research studies on the subject.”

Funding for his talk was provided by Abbott Nutrition.

Related blog posts:

 

 

 

More Evidence to Support Ethanol Locks

For many years, ethanol locks have been promoted as a way to reduce central catheter-associated bloodstream infections (CCABSI).  A recent study (Ardura M I, et al. JAMA Pediatr.doi.10.1001/jamapediatrics.2014.3291 -published online Feb 2, 2015, thanks to Ben Gold for this reference) showed a dramatic reduction in CCABSI among 24 children with intestinal failure.

This study examined outcomes from January 2011-Jan 2012 with the outcomes from February 2012-December 2013.  In the latter period, ethanol lock prophylaxis was added to the CCABSI “prevention bundle” both in inpatient and outpatient settings.

Key finding: Rates of CCABSI decreased from 6.99 per 1000 catheter days to 0.42 per 1000 catheter days.

One aspect of this study that is very important is that the QI team included a specialized CVC nurse who evaluated and performed all CVC care and teaching.

Their protocol is detailed in their methods section.  Some of the details:

  • Their ethanol lock utilized a 70% solution on a daily basis.
  • The CVC nurse verified that the catheter was silicone prior to initial lock.
  • CVC nurse used Alteplase prior to initial dwell.
  • Dwell volume was determined by CVC nurse by withdrawing flush until blood return and then adding 0.1 mL for children <15 kg and adding 0.2 mL for children >15 kg (max volume 3 mL).
  • Dwell times were minimum of 2 hours and maximum of 24 hours.
  • At the end of the dwell time, twice the amount of the predetermined ethanol volume was withdrawn and then 5 to 10 mL of normal saline was used as a flush.

Bottomline: Ethanol locks have the potential to reduce CCABSI by 90%; this can reduce hospitalizations, prevent complications, and possibly improve survival.

Related blog posts:

Heart-Shaped Polyp (from ACG twitter feed -recommends screening colonoscopy)

Heart-Shaped Polyp (from ACG twitter feed -recommends screening colonoscopy)

Update on Enteral Nutrition in Pediatric Intestinal Failure

It is always nice to see how other centers manage clinical problems.  In a recent review (J Pediatr 2014; 165: 1065-90) from Boston Children’s, the authors provide details on how they use enteral nutrition in pediatric intestinal failure (IF) patients.  Prior to reviewing their approach, the authors provide a few definitions:

  • “IF occurs when there is a reduction of functional intestinal mass necessary for adequate digestion and absorption for nutrient, fluid, and growth requirements, resulting in the need for intensive nutritional support.”
  • “IF resulting from extensive intestinal resection is termed SBS” (short bowel syndrome)

The authors also discuss intestinal adaptation and factors that predispose to improvement.  Enteral nutrition (EN) stimulates adaptation and ‘gut rest’ results in atrophy of intestinal mucosa.

Key points:

  • “Prompt initiation of enteral feeding after bowel resection has been shown to decrease the duration of hospitalization”
  • “The optimal choice for EN in infants with IF seems to be human milk…If human milk is unavailable, amino acid-based formulas have been associated with improved outcomes.”
  • If intact colon with ileocecal valve, supplementation with dietary fiber (e.g.. green beans) at 2 g/kg/d may be helpful.
  • In this population, there is a high prevalence of micronutrient deficiencies while on partial PN support, TPN (depending on availability of components), and when on exclusive enteral feedings.
  • “We commonly employ an approach that uses … continuous feeding at night and bolus feeding during the day.
  • Outcomes of IF are reviewed (noted in previous blog entry –see below). Citrulline can be useful predictor of enteral autonomy.

Feeding Advancement Principles -Figure 1:

When feeds are held, usually held for 8 hours and then restarted at 75% of previous rate

Stool output:

  • If <10 mL/kg/d or < 10 stools/d —->advance rate by 10-20 mL/kg/d
  • If 10-20 mL/kg/d or 10-12 stools/d —>no change
  • If >20 mL/kg/d or >12 stools/d  —->reduce or hold feeds

Ostomy output:

  • If 2 mL/kg/h —> advance rate by 10-20 mL/kg/d
  • If 2-3 mL/kg/h –>no change
  • If >3 mL/kg/h  –>reduce or hold feeds

Also suggested to reduce or holding feeds when/if:

  • signs of dehydration
  • stool reducing substances >1%
  • gastric aspirates > four times previous hour’s infusion rate

Oral feeds:

  • When developmentally appropriate, offer one hour’s worth of continuous feeds BID-TID after 5 days of continuous feeds.  Hold tube feeds during oral feeds.
  • More than an hour’s worth of oral feeds once infant has reached full volume of feeds by continuous route and gaining weight.

Take-home message: Outcomes of IF have improved.  This review provides one approach towards optimizing enteral nutrition.

Related blog posts:

 

Race Associated with Outcomes in Intestinal Failure

The best preparation for tomorrow is to do today’s work superbly well”  –William Osler (quote cited in NEJM 2014; 371: 1565-66).

The quote above is not directly related to today’s post but I liked it a lot.

While race “encompasses social, economic, and cultural issues,” it is a marker for health outcomes including in children with intestinal failure (JPGN 2014; 59: 537-43). This Pediatric Intestinal Failure Consortium study retrospectively analyzed 272 subjects, though 22 did not have adequate data regarding race.  In this cohort, there were 204 white and 46 nonwhite children.

Key findings:

  • Nonwhite children were more likely to die without an intestinal transplant (P<0.001). At 48 months after entry criteria were met, cumulative probability of death without an intestinal transplant was 0.40 for nonwhite children compared with 0.16 for white children.
  • Nonwhite children were less likely to receive an intestinal transplant (P=0.003). At 48 months after entry criteria were met, cumulative probability of receiving an intestinal transplant was 0.07 for nonwhite children compared with 0.31 for white children.

These findings held up when examined for biological factors like low birth rate and reason for intestinal transplantation; other factors that were accounted for included evidence of liver disease, residual bowel length, and whether child had received care at an intestinal transplantation center.  Even factors like receiving breast milk in the nursery were similar between the two groups.

Bottomline: Nonwhite race appears to be a marker for poor outcomes in children with intestinal failure.  Based on this retrospective data which examined multiple factors, the reasons do not have a biological basis.  As such, issues like barriers to treatment/access to care, social support, parental education, and cultural differences need to be considered.

 

Looking Beyond the Headline for Ultra-Short Bowel Syndrome

A quick glance at a recent study (JPGN 2014; 58: 438-42) suggests a favorable outlook for patients with ultra-short bowel syndrome (U-SBS). U-SBS has been defined as having a residual small bowel length <10 cm distal to the ligament of Treitz.  A more cynical definition by a colleague years ago was that U-SBS was when patients can fart and burp at the same time.

Looking at the details:  This study enrolled 11 patients into a prospective Italian database since 2000 and examined their outcomes.  Inclusion criteria included U-SBS diagnosed in the neonatal period (<28 days) and necessitating home parenteral nutrition at discharge.

The demographics note that these patients were bigger at birth and less premature than typical series of patients with SBS:

  • Only one of the patients had necrotizing enterocolitis as the sole underlying disease and six patients had volvulus.
  • All but two had ≥50% of their colons, with five having their entire colon.
  • All but one of these patients had gestational age ≥32 weeks and only two  patients had documented birth weight less than 2300 gm.

The authors note that these patients currently receive SMOFlipid as outpatients and Omegaven as inpatients.  All patients receive some enteral feedings.  Loperamide is used selectively.

Results:

  • Inpatient hospital care ranged from 23 to 104 days/year, but had improved during the last year of followup.
  • With >5 years of followup, 2 of the 11 patients had died.  One of these patients had severe intestinal failure associated liver disease (IFALD) despite use of Omegaven.
  • One patient underwent isolated intestinal transplantation.
  • No children in this series underwent a bowel-lengthening…”given the shortness of the residual small bowel, the gain of length after any procedure will not significantly improve absorption.”

Given their results, the authors note that despite recommendations for early referral for intestinal transplantation in patients with U-SBS, this may not result in a survival benefit.  They note a study by Pironi et al (Gut 2011; 60: 17-25) that showed that among 80 intestinal transplant candidates, 5-year survival was greater in those who were not transplanted.

Bottomline: This small cohort shows that certain populations of U-SBS may do well clinically for a long time with medical management. Caution should be used in extrapolating these results to SBS patients with different demographics.

Micronutrient Monitoring in Intestinal Failure

J Pediatr 2013; 163: 1692-6.  This retrospective study of prospectively collected data from 178 children provides data with regard to micronutrient deficiency among intestinal failure patients transitioning to enteral feeds. Figures 1 and 2 along with Table 2 provide the prevalence of micronutrient deficiency while receiving supplemental parenteral nutrition (PN) and while on full enteral nutrition (FEN).  Iron deficiency was most common in both situations with prevalence of 84% and 61% respectively. With the exception of folate (0%), all of the vitamins and micronutrients had fairly high rates of deficiency.  While on FEN,  deficiencies were  the following:

  • Vitamin A        19%
  • Vitamin B12    6.5%
  • Vitamin D        30%
  • Vitamin E          6%
  • Copper            8%
  • Iron                61%
  • Selenium         4%
  • Zinc               23%

The study does not indicate that the deficiency values were adjusted based on CRP values.  Instead, “low serum levels were used to define deficiencies.”  This is likely to lead to numerous errors.  Nevertheless, it is clear that these deficiencies are common.  Another finding of the study was that normal anthropometrics did not reduce the frequency of these deficiencies.  In their patient population, 57 of 136 (42%) with sufficient height and weight data had a height-for-age z-scores of <-2 by the time of FEN; where as 52 of 139 patients (37%) had weight-for-age z-scores of <-2.

A recent post on The Pediatric Nutritionist blog provides a suggested approach to the monitoring of vitamins and micronutrients based on the need for parenteral nutrition and on the need to consider inflammatory markers in the interpretation of these lab values: The Importance of Nutrition Lab Monitoring Protocols Featuring 

Bottomline: Vitamin and micronutrient deficiencies are common among intestinal failure patients.  In addition, a large percentage of these kids are not large at all.

Related blog post:

What happens to micronutrient levels in the hospital setting 

How long does it take the liver to recover from PNALD?

It takes a long time, even when there is no longer biochemical evidence of parenteral nutrition-associated liver disease (PNALD).  A recent study provides long-term data from a population-based, cross-sectional study on liver histology from pediatric intestinal failure (IF) patients (Hepatology 2013; 58: 729-38).  Patients were followed from 1984-2010.  IF was defined as having either >50% small bowel resection or need for PN >30 days.

The 38 IF participants had a median age of 7.2 years.  16 remained on PN after 74 months (range  2.5-204), 22 had weaned off PN 8.8 years (range 0.3-27) earlier after an average of 35 months of PN exposure.

Key findings:

  • Abnormal liver histology was present in 94% of patients on PN and 77% off PN.
  • Nearly 60% of patients on long-term PN had significant or severe fibrosis (Metavir stage ≥2).
  • Significant liver fibrosis and steatosis persisted after weaning off PN. That is, “liver histology remains abnormal up to 9 years after weaning off PN in the majority of IF patients.”
  • One patient off PN developed esophageal varices.
  • Risk factors for increased fibrosis: extensive small intestinal resection, (P=.002) loss of ileocecal valve (P=.048), and recurrent sepsis (P=.002).

Bottomline: While there have been important clinical advances in the management of IF, the data from this study indicate that many patients who have normal liver biochemistries continue to have abnormal liver histology.  Whether this will have an important clinical impact is not known.

Previous related blog entries:

Fish Oil, IFALD, and Liver Fibrosis

While there has been a lot of enthusiasm for the use of fish oil as a potential breakthrough for intestinal failure-associated liver disease, this has been based largely on the use of surrogate markers of liver disease and based on comparisons with the historical use of conventional intravenous lipids.  The latter problem has been discussed before on this blog (see links below).

A recent study begins to address the issue of surrogate markers by reinforcing the viewpoint that improvements in bilirubin and aminotransferases may not translate into improvement in liver fibrosis or other clinically-meaningful outcomes (JPGN 2013; 56: 364-69).  A previous pediatric study (J Pediatr 2010; 156: 327-31) showed failure of regression of hepatic fibrosis in 2 children receiving FOE therapy.

In this study, the authors sequentially examined 6 children on fish-oil lipid emulsions (FOE) who underwent multiple liver biopsies.  In this cohort, 5 of 6 children had gastroschisis and the mean gestational age was 35 weeks.  Median intestinal (small bowel) length beyond the ligament of Treitz was 26 cm and most children retained about 2/3rds of their colon.  Liver biopsies were obtained at the time of other open abdominal operations (eg. serial transverse enteroplasty, stoma takedown).

Key results:

  • Liver fibrosis persisted in 2 cases, progressed in 3 cases, and regressed in 1 case.
  • Histology and biochemistries indicated improvement in cholestasis and inflammation.
  • One patient has weaned off parenteral nutrition, two patients underwent isolated small bowel transplantation due to recurrent line infections, and three patients receive 25-40% of their calories parenterally.

The biggest limitation of this study besides the small number of enrolled patients was the relatively short  time period that was studied.  Only one patient who was studied had data reported for FOE more than 36 weeks.  The oldest age of any patient at the time of their last biopsy was 131 weeks old.

Take-home points:

  • “There is no direct evidence to support any one [proposed theoretical benefit of FOE] as clinically meaningful as yet.”
  • “Lipid minimization strategies are also effective in reducing cholestasis.”
  • “Many of the biopsies taken right at the time of FOE initiation” showed significant fibrosis which “speaks to how quickly fibrosis can develop.” One child had stage 2 fibrosis at 14 weeks of life.
  • “The biochemical resolution of cholestasis is at best a weak surrogate marker ..for…enteral independence and overall survival.”  “These findings make a strong case for early referral of children with short bowel syndrome to specialized intestinal rehabilitation centers.”

Related blog posts:

Green beans for short gut syndrome

A recent article indicates that the addition of green beans may improve diarrhea and reduce dependence on parenteral nutrition (Adding Dietary Green Beans to Formula Resolves the Diarrhea ) (ICAN. DOI: 10.1177/1941406412469403). Thanks to Kipp Ellsworth for pointing out this reference on his twitter feed.

This small retrospective study of 18 infants examined the addition of green beans to the diet of infants with short bowel syndrome (SBS) (1 jar of stage 2 baby food green beans to every 8 ounces of 30 cal formula).  The average gestational age of the patients was 32 weeks (range 23-39 weeks) and the average birth weight was 1938 gram.  Nine patients had NEC, four had gastroschisis, two had Christmas tree defect, and three had other reasons for either SBS or intestinal failure.  The IF group (n=10) was defined as being dependent on parenteral nutrition to meet nutritional needs; the SBS group (n=8), who were more severely affected, was defined as the malabsorptive state that follows a massive resection.

Products that were used:

  • Gerber Natural Select: 3 gm of fiber per 4 ounce
  • Beach-Nut Homestyle: 2 gm of fiber per 4 ounce
  • HyVee Mother Choice: 2 gm of fiber per 4 ounce
  • These products average 32% soluble and 68% insoluble fiber

While the authors note that they use only amino-acid based formulas currently, at the time of the study, 61% were receiving Peptamen Junior.

It is not clear in the manuscript exactly at what age green beans are introduced. However, a previous case study suggested addition of green beans at ~4 months or >44 weeks postconception.  This prior case study indicated that adding stage 2 green beans changed the caloric density of 30 cal formula to 22 cal/ounce (Nutrition in Clinical Practice 2005; 20: 674-77).  In addition, this adds 2 gm/kg/day of fiber.

Results from current study:

  • 9 of 10 IF patients were able to discontinue parenteral nutrition
  • 2 of 8 SBS patients were able to discontinue parenteral nutrition
  • All infants had improvements in stool consistency, typically within 24 hours of dietary change.

While the authors acknowledge the limitations of the study, they hypothesize that the reason for improvement is due to the fiber content of green beans.   Fermentation of dietary fiber produces short chain fatty acids (SCFAs) which in turn have a trophic effect on the mucosa and enhance nutrient absorption.

Studies have shown that adults with IF or SBS have improved stool consistency with the addition of fiber.  However, the authors note that there have been no studies documenting the effectiveness of dietary fiber in the pediatric SBS/IF population.

Whether green beans would outperform other sources of fiber like pectin, guar gum, bananas or benefiber is not clear.

Additional references/links:

IFfy outcome

More long-term data on the outcome of intestinal failure (IF) are available (Squire RH et al. J Pediatr 2012; 161: 723-8).

A retrospective analysis of infants <12 months (n=272) who were receiving parenteral nutrition (PN) for more than 60 days was performed by the Pediatric Intestinal Failure Consortium (PIFCon).  This study took place between January 2000-December 2007.

Key findings:

  • Etiologies: necrotizing enterocolitis (71, 26%), gastroschisis (44, 16%), atresia (27, 10%), volvulus (24, 9%), aganglionosis (11, 4%), other/multiple causes (94, 35%)
  • Residual small bowel length in 144 patients was 41 cm (25-65.5cm).
  • Catheter-related blood stream infections: 8.9 per 1000 catheter days.  (Newer techniques like antibiotic & ethanol locks were not commonly used during study period.)
  • Enteral autonomy continued into 5th year after study entry & occurred in 47%. Of the 154 patients who were alive without transplant, 27 remained on PN at the completion of the study period.  Of the patients who acheived enteral autonomy, this occurred in 31% of initial cohort  at 12 months, 40% by 24 months, 44% by 36 months, and 47% at 60 months.
  • At 72 months, a high incidence of death, 27%, was noted in this cohort. 58 died without transplantation & 10 deaths occurred in patients after transplant. Sepsis was 2nd leading cause of death (after multisystem organ failure).
  • At 72 months, cumulative percentage of intestinal transplantation was 26%.

Previous related blog entries: