Parenteral fish oil improves outcomes in patients with parenteral nutrition-associated liver injury. Ann Surg. 2009;250:395-402. [PMID: 19661785 DOI: 10.1097/sla.0b013e3181b36657]

The effect of lipid restriction on the prevention of parenteral nutrition-associated cholestasis in surgical infants

PURPOSE

Surgical infants requiring long-term parenteral nutrition (PN) are at risk for parenteral nutrition-associated liver disease (PNALD). The purpose of this study was to determine the effect of a lipid restricted PN regimen in preventing the development of PNALD in surgical infants.

METHODS

In 2009, we implemented a lipid restricted strategy in surgical infants expected to be on long-term PN using a soy-based lipid emulsion at a goal provision of 1g/kg/day throughout a patient's entire PN course. An experimental cohort of surgical infants treated with lipid restriction from 2009 to 2011 (n=82) was retrospectively compared to a control cohort of infants from 2005 to 2008 receiving standard intravenous lipid dosing (n=132). A multivariable relative risk regression model was constructed analyzing the association between lipid restriction and PNALD.

RESULTS

Patients admitted during the lipid restriction era had reduced daily lipid provisions compared to the control group (p<0.001). There were no significant differences in demographic or measured clinical characteristics between the two groups. A significant reduction in the incidence of PNALD was demonstrated in the lipid restricted group compared to the control group (22% vs. 43%, p=0.002). On multivariable relative risk regression, patients treated with standard lipid provisions were 1.77 times more likely to develop PNALD than patients who were lipid restricted (95% CI: 1.2-2.7; p=0.007).

CONCLUSION

Restriction of intravenous soy-based lipid in PN-fed surgical infants is associated with a reduction in the incidence of liver disease. Early lipid restriction should be considered in all surgical infants who require PN as a preventative measure against PNALD.

Intestinal mucosal defense system, Part 1. Consensus recommendations for immunonutrients

When microbial communities colonize in the developing intestinal tract after birth, microorganisms interact with specific apical surface receptors on the enterocytes. This interaction triggers a response that prevents overexpression of inflammatory cytokines, thus providing protection from pathogen-induced mucosal damage. Multiple immune modulatory factors in human milk and innate humoral factors also control inflammatory responses, providing additional protective effects. Our understanding of the role of the luminal microbial communities or microbiota is growing rapidly as novel technologies provide new insights into their taxonomy, function during early development, and impact on life-long health. Multiple studies have evaluated the effects of the specific nutrients, glutamine, arginine, nucleotides, polyunsaturated fatty acids, and lactoferrin, on disease outcomes in premature infants. These studies support a role for nutrients to modulate host defense mechanisms in premature infants, to develop normal digestive function, to protect from bacterial translocation, and to preserve mucosal barrier integrity. These effects are clearly important. However, not enough is yet known to design specific clinical care practices that support a healthy microbiota.

Lipids and liver dysfunction in patients receiving parenteral nutrition

PURPOSE OF REVIEW

Abnormalities of liver function tests are common in patients with intestinal failure receiving parenteral nutrition. Lipid emulsions have been implicated in the development of hepatobiliary disease in patients receiving parenteral nutrition.

RECENT FINDINGS

Lipid emulsions with reduced polyunsaturated fatty acids and specific ω6 : ω3 fatty acid ratios have been shown to have some beneficial effects on liver function, although the studies are small and generally of short duration in paediatric and adult patients.

SUMMARY

There is good evidence to suggest that the parenteral lipid dose should be less than 1 g/kg body weight/day, but this may not apply to all patients. The evidence is presented for the different lipid emulsions and their effect on liver function. The benefit of these emulsions compared with simply giving a lower lipid dose has yet to be studied.

Effects of ω-3 fish oil lipid emulsion combined with parenteral nutrition on patients undergoing liver transplantation

BACKGROUND

The effect of parenteral nutrition (PN) support supplemented with ω-3 fatty acids was investigated in a randomized, controlled clinical trial at the Affiliated Drum Tower Hospital, Medical School of Nanjing University.

MATERIALS AND METHODS

Ninety-eight patients with the diagnosis of end-stage liver disease or hepatic cellular carcinoma were admitted for orthotopic liver transplantation at the Affiliated Drum Tower Hospital. The patients were randomly divided into 3 groups: diet group (n = 32), PN group (n = 33), and polyunsaturated fatty acid (PUFA) group (n = 33). Patients in the PN and PUFA groups received isocaloric and isonitrogenous PN for 7 days after surgery. Venous heparin blood samples were obtained for assay on days 2 and 9 after surgery. A pathological test was performed after reperfusion of the donor liver and on day 9.

RESULTS

Alanine aminotransferase levels were improved significantly by PUFA treatment compared with traditional PN support (P < .05). Compared with the results on day 9 in the PN group, a significant difference was seen in the extent of increase of the prognostic nutrition index and prealbumin in the PUFA group. The pathological results also showed that ω-3 fatty acid supplementation reduced hepatic cell injury. PUFA therapy also decreased the incidence of infectious morbidities and shortened the posttransplant hospital stay significantly.

CONCLUSION

Posttransplant PN support can greatly improve metabolism of protein and nutrition states of patients. ω-3 fatty acid-supplemented PN significantly reduces injury of the transplanted liver, decreases the incidence of infectious morbidities, and shortens posttransplant hospital stay.

Short-term intravenous fish oil and pediatric intestinal failure associated liver disease: 3-year follow-up on liver function and nutrition

Intravenous fish oil (FO) has changed the management of intestinal failure associated liver disease (IFALD). This report describes two IFALD patients who received FO for 5 and 10 months, respectively and reports on their 3-year follow-up.

Pathogenesis and treatment of parenteral nutrition-associated liver disease

BACKGROUND

Parenteral nutrition-associated liver disease (PNALD) has been common in patients who require long-term parenteral nutrition. PNALD develops in 40%-60% of infants on long-term parenteral nutrition compared with 15%-40% of adults on home parenteral nutrition for intestinal failure. The pathogenesis of PNALD is multifactorial and remains unclear. There is no specific treatment. Management strategies for its prevention and treatment depend on an understanding of many risk factors. This review aims to provide an update on the pathogenesis and treatment of this disease.

DATA SOURCES

A literature search was performed on the MEDLINE and Web of Science databases for articles published up to October 2011, using the keywords: parenteral nutrition associated liver disease, intestinal failure associated liver disease, lipid emulsions and fish oil. The available data reported in the relevant literatures were analyzed.

RESULTS

The literature search provided a huge amount of evidence about the pathogenesis and management strategies on PNALD. Currently, lack of enteral feeding, extended duration of parenteral nutrition, recurrent sepsis, and nutrient deficiency or excess may play important roles in the pathogenesis of PNALD. Recent studies found that phytosterols, present as contaminants in soy-based lipid emulsions, are also an important factor in the pathogenesis. Moreover, the treatment of PNALD is discussed.

CONCLUSIONS

The use of lipid emulsions, phytosterols in particular, is associated with PNALD. Management strategies for the prevention and treatment of PNALD include consideration of early enteral feeding, the use of specialized lipid emulsions such as fish oil emulsions, and isolated small bowel or combined liver and small bowel transplantation. A greater understanding of the pathogenesis of PNALD has led to promising interventions to prevent and treat this condition. Future work should aim to better understand the mechanisms of PNALD and the long-term outcomes of its treatment.

The use of fish oil lipid emulsion in the treatment of intestinal failure associated liver disease (IFALD)

Since 2004, fish oil based lipid emulsions have been used in the treatment of intestinal failure associated liver disease, with a noticeable impact on decreasing the incidence of morbidity and mortality of this often fatal condition. With this new therapy, however, different approaches have emerged as well as concerns about potential risks with using fish oil as a monotherapy. This review will discuss the experience to date with this lipid emulsion along with the rational for its use, controversies and concerns.

Fish oil emulsions in the management of intestinal failure-associated liver disease

The role of parenteral lipid emulsions in the treatment of intestinal failure-associated liver disease (IFALD) is both topical and controversial. There is strong evidence supporting plant-based (soy, olive) lipid emulsions as a key cause for IFALD, especially in neonates. As a result, alternate lipid formulations, most notably fish oil emulsions (FOE) have come into widespread use despite somewhat limited clinical data on their overall benefit and potential long-term consequences. This review examines putative mechanisms of action of FOE in reversing cholestasis associated with IFALD, and critically reviews published clinical studies of the use of FOE in pediatric patients with IFALD. From these works, it appears the mechanism of action of FOE is most likely related to the reduction of serum phytosterols associated with plant-based lipid emulsions rather than a specific positive benefit of the fish oils themselves. Although the use of FOE seems to correlate with a reduction in cholestasis, their actual individual benefit is not established, and data on long-term outcomes and safety are not yet available.

Review and clinical update on parenteral nutrition-associated liver disease

Parenteral nutrition-associated liver disease (PNALD) is a complex disease that is diagnosed by clinical presentation, biochemical markers of liver injury, concurrent use of parenteral nutrition (PN), and negative workup for other causes of liver disease. Since the first case of PNALD was reported more than 30 years ago, clinicians have had few effective treatments for PNALD, and when disease progressed to liver cirrhosis, it was historically associated with poor outcomes. Within the past 5 years, there has been much excitement about new treatments for PNALD, including use of both parenteral and enteral ω-3 polyunsaturated long-chain fatty acids (ω-3 PUFA) as well as restricting dosing of ω-6 PUFA. Scientists are also interested in uncovering the mechanisms associated with liver injury seen in PNALD. This article reviews the recent literature relating to the pathophysiology and treatment of PNALD.

Neonatal short bowel syndrome as a model of intestinal failure: physiological background for enteral feeding

Intestinal failure (IF) is a well identified clinical condition, which is characterised by the reduction of functional gut capacity below the minimum needed for adequate digestion and absorption of nutrients for normal growth in children. Short bowel syndrome (SBS) is the leading cause of IF in neonates, infants and young children usually as a result of extensive intestinal resection during the neonatal period. Simultaneously maintaining optimal nutritional status and achieving intestinal adaptation is a clinical challenge in short bowel patients. Both growth and development of the child as well as gut adaptation should be considered synergistically as primary outcome parameters. Enteral nutrition (EN) can be introduced orally and/or by tube feeding (TF). Several controversies over nutritional treatment of children with SBS related intestinal failure remain. As reported from different centres around the world, most practices are more "experienced based" rather than "evidence based". This is partly due to the small number of patients with this condition. This review (based on a consensus) discusses the physiological principles and nutritional management, including the type of diet and route of delivery. Perspectives in optimizing intestinal adaptation and reducing the consequences of small intestinal bacterial overgrowth are also discussed.

Cholestasis and growth in neonates with gastroschisis

PURPOSE

The aim of this study was to determine the incidence of cholestasis and the correlation between cholestasis and weight-for-age z scores in parenteral nutrition-dependent neonates with gastroschisis.

METHODS

A single-center retrospective review of 59 infants born with gastroschisis from January 2000 to June 2007 was conducted. Demographic and clinical data were collected and analyzed. Subjects were divided into cholestatic and noncholestatic groups. Statistical analyses included the Student t test, Wilcoxon rank sum test, Fisher exact test, and a general linear model.

RESULTS

Fifty-nine neonates with gastroschisis were identified, and 16 (28%) of 58 patients developed cholestasis. Younger gestational age and cholestasis were found to be independently associated with weight-for-age z score in 30 of 58 patients with available long-term follow-up data.

CONCLUSIONS

Parenteral nutrition-dependent neonates with gastroschisis remain at considerable risk for the development of cholestasis. Both gestational age and cholestasis were found to be independent risk factors, predisposing these neonates to poor postnatal growth.

Steroidal compounds in commercial parenteral lipid emulsions

Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn(®) II, Liposyn(®) III, Lipofundin(®) MCT, Lipofundin(®) N, Structolipid(®), Intralipid(®), Ivelip(®) and ClinOleic(®). Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction.

Provision of a soy-based intravenous lipid emulsion at 1 g/kg/d does not prevent cholestasis in neonates

BACKGROUND

One of the most common and severe complications of long-term parenteral nutrition (PN) is PN-associated cholestasis. The soybean oil-based lipid emulsion administered with PN has been associated with cholestasis, leading to an interest in lipid reduction strategies. The purpose of this study was to determine whether the provision of a soybean oil-based lipid emulsion at 1 g/kg/d compared with 2-3 g/kg/d is associated with a reduced incidence of cholestasis.

METHODS

Retrospective review of neonates admitted between 2007 and 2011 with a gastrointestinal condition necessitating ≥ 21 days of PN support. Neonates were divided into 2 groups based on the intravenous lipid emulsion dose: 1-g group (1 g/kg/d) and 2- to 3-g group (2-3 g/kg/d). The primary outcome measure was the incidence of cholestasis.

RESULTS

Sixty-one patients met inclusion criteria (n = 29, 1-g group; n = 32, 2- to 3-g group). The 2 groups did not differ in any baseline characteristics other than associated comorbidities that were more common in the 2- to 3-g group. The duration of PN, the number of operative procedures and bloodstream infections, and enteral nutrition (EN) were similar between groups. The incidence of cholestasis was not different between groups (51.7%, 1-g group; 43.8%, 2- to 3-g group; P = .61), and there was no difference between groups in the time to cholestasis (32.6 ± 24.1 days, 1-g group; 27.7 ± 10.6 days, 2- to 3-g group; P = .48). Overall, 44.8% of patients with cholestasis were transitioned to full EN, and 55.2% were transitioned to a fish oil-based lipid emulsion after which the direct bilirubin normalized in all patients.

CONCLUSION

Lipid reduction to 1 g/kg/d does not prevent or delay the onset of cholestasis in neonates.

Dietary fish oil aggravates paracetamol-induced liver injury in mice

BACKGROUND

Paracetamol (APAP) hepatotoxicity remains the leading cause of drug-induced liver failure. Fish oil, which contains ω-3 fatty acids, has demonstrated therapeutic efficacy in several models of liver disease. Evidence for its use in APAP intoxication, however, is conflicting. The effects of fish oil supplementation on APAP-induced liver failure were investigated.

METHODS

Ten C57BL6/J mice were fed a diet based on menhaden fish oil (MEN) or soybean oil (SOY) for 3 weeks followed by APAP intoxication. In a second experiment, the prefeeding period was reduced to 5 days. In a third experiment, 10 mice received the study diets for 3 weeks, after which they received chronic, low-dose APAP administration for another 4 weeks. Finally, 10 mice received oral parenteral nutrition supplemented with either intravenous (IV) soybean-based or fish oil-based lipid emulsion for 19 days, followed by APAP intoxication.

RESULTS

The extent of hepatocellular necrosis (3.8 ± 0.2 vs 2.8 ± 0.2; P = .021) and serum alanine aminotransferase values (2807 ± 785 vs 554 ± 141 IU/L; P = .048) were significantly elevated in mice fed a MEN diet compared with SOY-diet fed controls. Long-term, low-dose APAP administration did not lead to liver injury irrespective of study diet. Pretreatment with soybean- or fish oil-based IV lipid emulsions followed by APAP intoxication demonstrated no significant differences in hepatic injury between groups.

CONCLUSION

Within therapeutic ranges, APAP is harmless to the liver irrespective of dietary fat composition. IV use of fish oil did not increase APAP-induced hepatotoxicity, but animals fed a fish oil-based diet were more susceptible, rather than resistant, to APAP-induced hepatotoxicity.

[Guidelines for specialized nutritional and metabolic support in the critically-ill patient. Update. Consensus of the Spanish Society of Intensive Care Medicine and Coronary Units-Spanish Society of Parenteral and Enteral Nutrition (SEMICYUC-SENPE): liver failure and transplantation]

Patients with liver failure have a high prevalence of malnutrition, which is related to metabolic abnormalities due to the liver disease, reduced nutrient intake and alterations in digestive function, among other factors. In general, in patients with liver failure, metabolic and nutritional support should aim to provide adequate nutrient intake and, at the same time, to contribute to patients' recovery through control or reversal of metabolic alterations. In critically-ill patients with liver failure, current knowledge indicates that the organ failure is not the main factor to be considered when choosing the nutritional regimen. As in other critically-ill patients, the enteral route should be used whenever possible. The composition of the nutritional formula should be adapted to the patient's metabolic stress. Despite the physiopathological basis classically described by some authors who consider amino acid imbalance to be a triggering factor and key element in maintaining encephalopathy, there are insufficient data to recommend "specific" solutions (branched-chain amino acid-enriched with low aromatic amino acids) as part of nutritional support in patients with acute liver failure. In patients undergoing liver transplantation, nutrient intake should be started early in the postoperative period through transpyloric access. Prevention of the hepatic alterations associated with nutritional support should also be considered in distinct clinical scenarios.

Parenteral ω-3 fatty acid lipid emulsions for children with intestinal failure and other conditions: a systematic review

BACKGROUND

There is growing interest in the use of ω-3 fatty acid (n-3FA) lipid emulsions to prevent complications associated with parenteral nutrition. The authors systematically reviewed the evidence on the benefits and safety of n-3FA compared with standard lipid emulsions in children with intestinal disease, critical illness, trauma, or postoperative complications.

MATERIALS AND METHODS

The authors searched 4 bibliographic databases from their inception to March 2011, conference proceedings, trial registries, and reference lists. Two reviewers independently selected studies, assessed methodological quality, and rated the strength of the evidence. One reviewer extracted and a second reviewer verified data. The authors summarized findings qualitatively and conducted meta-analysis when appropriate.

RESULTS

Five randomized controlled trials with unclear risk of bias and 3 high-quality prospective cohort studies were included. The studies examined premature, low birth weight infants (n = 6) and children with heart disease (n = 1) or intestinal failure (n = 1). The strength of evidence was consistently low or very low across all lipid emulsion comparisons and outcomes. In young children, n-3FA emulsions resulted in improvement in some biochemical outcomes of intestinal failure-associated liver disease but no difference in mortality. Few studies examined patient-important outcomes, such as length of hospital and intensive care stay; need for transplantation, growth, and cognitive development; or the long-term effects and potential harms associated with these therapies.

CONCLUSIONS

Currently, there is a lack of sufficient high-quality data to support the use of parenteral n-3FA lipid emulsions in children. Future trials examining long-term clinical outcomes and harms are needed.

Short bowel syndrome in children: current and potential therapies

Short bowel syndrome (SBS) reflects a state of malabsorption that occurs due to loss of a significant portion of the small bowel. The pathophysiology of SBS is determined largely by the process of adaptation, which is the innate attempt by the remnant portions of the intestine to increase fluid and nutrient reabsorption. In recent years, emphasis has been placed on intestinal rehabilitation with multidisciplinary teams as a comprehensive approach to the management of patients with SBS. In our institution, the multidisciplinary team members include pediatric gastroenterologists, pediatric surgeons, pediatric dieticians, physical therapists, occupational therapists, neonatologists (especially for patients still under their care), transplant surgeons, transplant coordinators and social workers. Parenteral nutrition plays a significant role in the management of SBS, but its use is associated with many potential complications, including cholestatic liver disease. Fish oil-based lipid emulsions have shown promise in their ability to reverse and also prevent the development of cholestasis in these patients. Clinical trials have shown that growth factors and other trophic hormones facilitate the process of adaptation. The most significant impact has been shown with the use of glucagon-like peptide-2 and its analog (teduglutide). Surgical interventions remain an important part of the management of SBS to facilitate adaptation and treat complications. Intestinal transplantation is a last resort option when the process of adaptation is unsuccessful. This review article is intended to provide an overview of the conventional and emerging therapies for pediatric SBS.

Resolution of parenteral nutrition-associated jaundice on changing from a soybean oil emulsion to a complex mixed-lipid emulsion

BACKGROUND AND OBJECTIVE

Resolution of parenteral nutrition (PN)-associated jaundice has been reported in children given a reduced dose of intravenous fat using a fish oil-derived lipid emulsion. The aim of the present study was to examine the effect on PN-associated jaundice of changing from a soybean oil-derived lipid to a mixed lipid emulsion derived from soybean, coconut, olive, and fish oils without reducing the total amount of lipid given.

METHODS

Retrospective cohort comparison examining serum bilirubin during 6 months in children with PN-associated jaundice who changed to SMOFlipid (n=8) or remained on Intralipid (n=9).

RESULTS

At entry, both groups received most of their energy as PN (SMOFlipid 81.5%, range 65.5-100 vs Intralipid 92.2%, range 60.3-100; P=0.37). After 6 months, both tolerated increased enteral feeding but still received large proportions of their energy as PN (SMOFlipid 68.4%, range 36.6-100 vs Intralipid 50%, range 37.6-76; P=0.15). The median bilirubin at the outset was 143 μmol/L (range 71-275) in the SMOFlipid group and 91 μmol/L (range 78-176) in the Intralipid group. After 6 months, 5 of 8 children in the SMOFlipid and 2 of 9 children in the Intralipid group had total resolution of jaundice. The median bilirubin fell by 99 μmol/L in the SMOFlipid group but increased by 79 μmol/L in the Intralipid group (P=0.02).

CONCLUSIONS

SMOFlipid may have important protective properties for the liver and may constitute a significant advance in PN formulation. Randomised trials are needed to study the efficacy of SMOFlipid in preventing PN liver disease.

Parenteral plant sterols and intestinal failure-associated liver disease in neonates

OBJECTIVES

We prospectively evaluated incidence of prolonged (>28 days) parenteral nutrition (PN), associated complications, and significance of parenteral plant sterols (PS) in neonatal intestinal failure-associated liver disease (IFALD) compared with children.

METHODS

We recruited 28 neonates (mean age 50 days, range 28-126) and 11 children (6.9 y, 2.1-16.6) in all of Finland. Patients underwent repeated measurements of serum cholesterol, noncholesterol sterols, including PS, cholestanol and cholesterol precursors, and liver biochemistry during and 1 month after discontinuation of PN. Healthy matched neonates (n=10) and children (n=22) served as controls.

RESULTS

IFALD occurred more frequently among neonates (63%) than children (27%; P<0.05). Ratios of serum PS, including stigmasterol, sitosterol, avenasterol, and campesterol, and total PS were increased among neonates compared with healthy controls and children on PN by 2- to 22- and 2- to 5-fold (P<0.005), respectively. Neonates with IFALD had significantly higher ratios of serum PS and cholestanol compared with neonates without IFALD (P<0.05). Total duration of PN associated with serum cholestanol, stigmasterol, avenasterol, alanine aminotransferase, and aspartate aminotransferase (r=0.472-0.636, P<0.05). Cholestanol and individual serum PS, excluding campesterol, reflected direct bilirubin (r=0.529-0.688, P<0.05). IFALD persisted after discontinuation of PN in 25% of neonates with 4.2- and 2.2-times higher ratios of serum stigmasterol and cholestanol compared with neonates without IFALD (P<0.05).

CONCLUSIONS

Frequent occurrence of IFALD among neonates on PN displays an association to duration of PN and markedly increased serum PS, especially stigmasterol, in comparison to healthy neonates and children on PN. Striking accumulation of parenteral PS may contribute to IFALD among neonates.

Comparison of the effects of different intravenous fat emulsions in patients with systemic inflammatory response syndrome and sepsis

BACKGROUND

In this study, the authors aimed to compare the effects that a medium- and long-chain triglyceride (MCT/LCT) fat infusion and a fish oil-based (ω-3) fat infusion for parenteral nutrition (PN) had on systemic inflammation, cytokine response, and hepatic steatosis in mixed intensive care unit (ICU) patients.

METHODS

This was a single-center, placebo-controlled, randomized clinical trial in a university hospital. Four patient groups, including systemic inflammatory response syndrome (SIRS) and sepsis patients, were assigned to receive PN employing the MCT/LCT fat infusion or the fish oil-based fat infusion over 7 days. Blood biochemistry and liver steatosis were evaluated.

RESULTS

Twenty sepsis and 20 SIRS patients were included in this study. There was no statistically significant difference in terms of biochemical values and Acute Physiology and Chronic Health Evaluation II scores between the different feeding groups. Sepsis groups who received MCT/LCT revealed higher grades of liver steatosis by ultrasound on days 7 and 10 (P < .05). Tumor necrosis factor (TNF)-α and interleukin (IL)-6 values in sepsis group 1 (S1) were higher than in sepsis group (S2) on day 7, whereas IL-1 values were higher on days 3, 7, and 10 in group S1 than in group S2. Conversely, IL-10 values on days 3 and 7 were significantly higher in group S2.

CONCLUSION

Fish oil-based fat emulsions might have anti-inflammatory and hepatoprotective effects in hyperinflammatory disease such as sepsis.

Beneficial effect of docosahexaenoic acid on cholestatic liver injury in rats

Bile duct obstruction and subsequent cholestasis are associated with hepatocellular injury, cholangiocyte proliferation, stellate cell activation, Kupffer cell activation, oxidative stress, inflammation and fibrosis. Docosahexaenoic acid (DHA) is an essential polyunsaturated fatty acid that has been shown to possess health beneficial effects, including hepatoprotection. However, the molecular mechanism of DHA-mediated hepatoprotection is not fully understood. In the present study, we report the protective effect of DHA on cholestatic liver injury. Cholestasis was produced by bile duct ligation (BDL) in male Sprague-Dawley rats for 3 weeks. Daily administration of DHA was started 2 weeks before injury and lasted for 5 weeks. In comparison with the control group, the BDL group showed hepatic damage as evidenced by histological changes and elevation in serum biochemicals, ductular reaction, fibrosis, inflammation and oxidative stress. These pathophysiological changes were attenuated by chronic DHA supplementation. DHA alleviated BDL-induced transforming growth factor beta-1 (TGF-β1), intereukin-1beta, connective tissue growth factor and collagen expression. The anti-fibrotic effect of DHA was accompanied by reductions in α-smooth muscle actin-positive matrix-producing cells and Smad 2/3 activity critical to the fibrogenic potential of TGF-β1. DHA also attenuated BDL-induced leukocyte accumulation and nuclear factor-κB (NF-κB) activation. Further studies demonstrated an inhibitory effect of DHA on redox-sensitive intracellular signaling molecule extracellular signal-regulated kinase (ERK). Taken together, the hepatoprotective, anti-inflammatory and anti-fibrotic effects of DHA seem to be multifactorial. The beneficial effects of chronic DHA supplementation are associated with anti-oxidative and anti-inflammatory potential as well as down-regulation of NF-κB and transforming growth factor beta/Smad signaling probably via interference with ERK activation.

Intravenous fat emulsions reduction for patients with parenteral nutrition-associated liver disease

OBJECTIVE

To test the hypothesis that implementation of a marked reduction in intravenous fat will result in reversal of parenteral nutrition-associated liver disease (PNALD) in infants.

STUDY DESIGN

Prospective study of intravenous fat emulsion reduction in parenteral nutrition to 1 g/kg/d 2 times per week in neonates diagnosed with PNALD. Primary outcome measure was total bilirubin levels compared with gestational age, birth weight, and diagnosis-matched historical controls receiving 3 g/kg/d of intravenous lipids.

RESULTS

Intravenous fat emulsion reduction resulted in a significant decline in total bilirubin levels compared with controls. Comparison of growth in the 2 groups was similar. Mild essential fatty acid deficiency was detected in 8 of 31 infants and was reversed with additional days of lipid infusion. No significant adverse events were noted.

CONCLUSIONS

An association between intravenous lipid emulsion administration and the development of PNALD seems probable. Use of intravenous fat emulsion reduction is a potential approach to reverse PNALD in young infants. Frequent monitoring of essential fatty acid deficiency is needed with the use of this regimen.

Current status of pediatric intestinal failure, rehabilitation, and transplantation: summary of a colloquium

An international symposium convened September 9-11, 2010, in Chicago to present the state of the art and science of the multidisciplinary care of intestinal failure in children. Medical and surgical management of the child with intestinal failure was presented with a focus on the importance of multidisciplinary intestinal failure management. Issues of timing of referral and benefit risk analysis for intestine "rehabilitation" and transplant were presented. Areas of opportunity such as increased donor recovery, improvement of long-term transplant outcomes, optimization of immune monitoring, and quality-of-life outcomes were reviewed.

Ethanol locks to prevent catheter-related bloodstream infections in parenteral nutrition: a meta-analysis

OBJECTIVE

Patients with pediatric intestinal failure (IF) depend on parenteral nutrition for growth and survival, but are at risk for complications, such as catheter-related bloodstream infections (CRBSIs). CRBSI prevention is crucial, as sepsis is an important cause of IF-associated liver disease and mortality. We aim to estimate the pooled effectiveness and safety of ethanol locks (ELs) in comparison with heparin locks (HLs) with regard to CRBSI rate and catheter replacements for pediatric IF patients with chronic parenteral nutrition dependence.

METHODS

A systematic review without language restriction was performed on Medline (1948-2010), Embase (1980-2010), and conference programs and trial registries up to December 2010. Search terms included "Catheter-Related Infections," "Catheter," "Catheters, Indwelling," "alcohol," "ethanol," and "lock." Two authors identified 4 retrospective studies for the pediatric IF population. Double, independent data extraction using predefined data fields and risk of bias assessment (Newcastle-Ottawa scale) was performed.

RESULTS

In comparison with HLs, ELs reduced the CRBSI-rate per 1000 catheter days by 7.67 events and catheter replacements by 5.07. EL therapy decreased the CRBSI rate by 81% and replacements by 72%. One hundred eight to 150 catheter days of EL exposure were necessary to prevent 1 CRBSI and 122 to 689 days of exposure avoided 1 catheter replacement. Adverse events were rare and included thrombotic events.

CONCLUSIONS

In pediatric patients with IF, EL is a more effective alternative to HL. Adverse events include thrombotic events.

Improved outcome in neonatal short bowel syndrome using parenteral fish oil in combination with ω-6/9 lipid emulsions

BACKGROUND

Newborn infants with short bowel syndrome (SBS) represent a high-risk group of developing intestinal failure-associated liver disease (IFALD), which may be fatal. However, infants have a great capacity for intestinal growth and adaptation if IFALD can be prevented or reversed. A major contributing factor to IFALD may be the soybean oil-based intravenous lipid emulsions used since the introduction of parenteral nutrition (PN) 40 years ago.

METHODS

This retrospective study compares the outcome in 20 neonates with SBS treated with parenteral fish oil (Omegaven) in combination with ω-6/9 lipid emulsions (ClinOleic) with the outcome in a historical cohort of 18 patients with SBS who received a soybean oil-based intravenous lipid emulsion (Intralipid).

RESULTS

Median gestational age was 26 weeks in the treatment group and 35.5 weeks in the historical group. All patients were started on PN containing Intralipid that was switched to ClinOleic/Omegaven in the treatment group at a median age of 39 gestational weeks. In the treatment group, direct bilirubin levels were reversed in all 14 survivors with cholestasis (direct bilirubin >50 umol/L). Median time to reversal was 2.9 months. Only 2 patients died of liver failure (10%). In the historical cohort, 6 patients (33%) died of liver failure, and only 2 patients showed normalization of bilirubin levels.

CONCLUSIONS

Parenteral fish oil in combination with ω-6/9 lipid emulsions was associated with improved outcome in premature neonates with SBS. When used instead of traditional soybean-based emulsions, this mixed lipid emulsion may facilitate intestinal adaptation by increasing the IFALD-free period.

Parenteral nutrition supplementation in biliary atresia patients listed for liver transplantation

The objective of this study was to determine the impact of parenteral nutrition (PN) on the outcomes of biliary atresia (BA) patients listed for liver transplantation (LT). We retrospectively reviewed the charts of all BA patients at our institution who underwent hepatoportoenterostomy and were listed for LT before the age of 36 months between 1990 and 2010. The initiation of PN was based on clinical indications. Twenty-five PN subjects and 22 non-PN subjects (74% female) were studied. The median PN initiation age was 7.7 months, the mean duration was 86 days, and the mean amount of energy supplied by PN was 77 kcal/kg/day. Before PN, the triceps skinfold thickness (TSF) and the mid-arm circumference (MAC) z scores were decreasing. After PN, TSF (P < 0.001) and MAC (P < 0.001) improved significantly. The PN group had lower MAC and TSF scores than the non-PN group at the time of LT listing. Between listing and LT, MAC and TSF improved in the PN group and worsened in the non-PN groups; as a result, the 2 groups had the same z scores at LT. The PN group had a higher incidence of gastrointestinal bleeding and ascites before LT, but there were no differences in the rates of pre-LT bacteremia, days in the intensive care unit after LT, or patient or graft survival. In conclusion, PN improves the nutritional status of malnourished BA patients awaiting LT, and this is associated with post-LT outcomes comparable to those of patients not requiring PN.

Parenteral nutrition-associated cholestasis: an American Pediatric Surgical Association Outcomes and Clinical Trials Committee systematic review

OBJECTIVE

The aim of this study was to review evidence-based data addressing key clinical questions regarding parenteral nutrition-associated cholestasis (PNAC) and parenteral nutrition-associated liver disease (PNALD) in children.

DATA SOURCE

Data were obtained from PubMed, Medicine databases of the English literature (up to October 2010), and the Cochrane Database of Systematic Reviews.

STUDY SELECTION

The review of PNAC/PNALD has been divided into 4 areas to simplify one's understanding of the current knowledge regarding the pathogenesis and treatment of this disease: (1) nonnutrient risk factors associated with PNAC, (2) PNAC and lipid emulsions, (3) nutritional (nonlipid) considerations in the prevention of PNAC, and (4) supplemental medications in the prevention and treatment of PNAC.

RESULTS

The data for each topic area relevant to the clinical practice of pediatric surgery were reviewed, evaluated, graded, and summarized.

CONCLUSIONS

Although the conditions of PNAC and PNALD have been well recognized for more than 30 years, only a few concrete associations and treatment protocols have been established.

Use of an omega-3 fatty acid-based emulsion in the treatment of parenteral nutrition-induced cholestasis in patients with microvillous inclusion disease

Microvillous inclusion disease is a congenital intestinal epithelial cell disorder leading to lifelong intestinal failure. In this report, we discuss the use of a fish oil-based lipid emulsion in the treatment of 3 patients with microvillous inclusion disease who developed parenteral nutrition-associated liver disease.

Docosahexaenoic acid and arachidonic acid prevent essential fatty acid deficiency and hepatic steatosis

OBJECTIVES

Essential fatty acids are important for growth, development, and physiologic function. α-Linolenic acid and linoleic acid are the precursors of docosahexaenoic and arachidonic acid, respectively, and have traditionally been considered the essential fatty acids. However, the authors hypothesized that docosahexaenoic acid and arachidonic acid can function as the essential fatty acids.

METHODS

Using a murine model of essential fatty acid deficiency and consequent hepatic steatosis, the authors provided mice with varying amounts of docosahexaenoic and arachidonic acids to determine whether exclusive supplementation of docosahexaenoic and arachidonic acids could prevent essential fatty acid deficiency and inhibit or attenuate hepatic steatosis.

RESULTS

Mice supplemented with docosahexaenoic and arachidonic acids at 2.1% or 4.2% of their calories for 19 days had normal liver histology and no biochemical evidence of essential fatty acid deficiency, which persisted when observed after 9 weeks.

CONCLUSION

Supplementation of sufficient amounts of docosahexaenoic and arachidonic acids alone without α-linolenic and linoleic acids meets essential fatty acid requirements and prevents hepatic steatosis in a murine model.

Effect of omega-3 polyunsaturated fatty acids to reverse biopsy-proven parenteral nutrition-associated liver disease in adults

BACKGROUND & AIMS

Parenteral nutrition-associated liver disease (PNALD) complicates the treatment of patients with short bowel syndrome (SBS). Some studies have shown omega-3 polyunsaturated fatty acids (ω-3 PUFAs) have favorable effects in treating PNALD in children. We, therefore, investigate the effects of ω-3 PUFAs supplemented intravenous lipid emulsion (ILE) on PNALD in adults.

METHODS

We performed an open-labeled study of a ω-3 PUFAs based ILE in 15 adults with SBS who developed cholestasis while receiving soybean oil-based ILE. Liver biopsies were performed before and after the initiation of ω-3 PUFAs to confirm the presence and improvement of cholestasis. Blood samples were collected every week for analysis of fatty acid composition and liver function.

RESULTS

12 of the 15 patients had their direct bilirubin normalized within 4 weeks and our data demonstrated a significant decrease in both DB (P ≤ 0.001) and TB (P ≤ 0.001) after 4 weeks compared to baseline. There were ameliorations of liver function and fatty acid patterns in all patients and serial liver biopsy specimens showed progressive histologic improvement.

CONCLUSIONS

Parenteral ω-3 PUFAs supplemented fat emulsions are safe and effective in the treatment of PNALD in adults.

A contemporary analysis of parenteral nutrition-associated liver disease in surgical infants

BACKGROUND/PURPOSE

Despite advances in pediatric nutritional support and a renewed focus on management of intestinal failure, there are limited recent data regarding the risk of parenteral nutrition (PN)-associated liver disease in surgical infants. This study investigated the incidence of cholestasis from PN and risk factors for its development in this population.

METHODS

A retrospective review was performed of all neonates in our institution who underwent abdominal surgery and required postoperative PN from 2001 to 2006. Cholestasis was defined as 2 conjugated bilirubin levels greater than 2 mg/dL over 14 days. Nonparametric univariate analyses and multivariate logistic regression were used to model the likelihood of developing cholestasis. Median values with range are presented.

RESULTS

One hundred seventy-six infants met inclusion criteria, and patients received PN for 28 days (range, 2-256 days). The incidence of cholestasis was 24%. Cholestatic infants were born at an earlier gestational age (34 vs 36 weeks; P < .01), required a 3-fold longer PN duration (76 vs 21 days; P < .001), had longer inpatient stays (86 vs 29 days; P < .001), and were more likely to be discharged on PN. The median time to cholestasis was 23 days. Cholestasis was an early development; 77% of cholestatic infants developed cholestasis by 5 weeks of PN exposure. On multivariate regression, only prematurity was significantly associated with development of cholestasis (P < .05).

CONCLUSION

In this analysis, the development of PN-associated liver disease occurred early in the course of exposure to PN. These data help to define the time course and prognosis for PN-associated cholestasis in surgical infants.

Parenteral fish-oil-based lipid emulsion improves fatty acid profiles and lipids in parenteral nutrition-dependent children

BACKGROUND

Total parenteral nutrition (PN), including fat administered as a soybean oil-based lipid emulsion (SOLE), is a life-saving therapy but may be complicated by PN-induced cholestasis and dyslipidemia. A fish-oil-based lipid emulsion (FOLE) as a component of PN can reverse PN-cholestasis and has been shown to improve lipid profiles.

OBJECTIVE

The objective was to describe changes in the fatty acid and lipid profiles of children with PN-cholestasis who were treated with a FOLE.

DESIGN

Lipid and fatty acid profiles of 79 pediatric patients who developed PN-cholestasis while receiving standard PN with a SOLE were examined before and after the switch to a FOLE. All patients received PN with the FOLE at a dose of 1 g · kg(-1) · d(-1) for ≥1 mo.

RESULTS

The median (interquartile range) age at the start of the FOLE treatment was 91 (56-188) d. After a median (interquartile range) of 18.3 (9.4-41.4) wk of receiving the FOLE, the subjects' median total and direct bilirubin improved from 7.9 and 5.4 mg/dL to 0.5 and 0.2 mg/dL, respectively (P < 0.0001). Serum triglyceride, total cholesterol, LDL, and VLDL concentrations significantly decreased by 51.7%, 17.4%, 23.7%, and 47.9%, respectively.

CONCLUSIONS

The switch from a SOLE to a FOLE in PN-dependent children with cholestasis and dyslipidemia was associated with a dramatic improvement in serum triglyceride and VLDL concentrations, a significant increase in serum omega-3 (n-3) fatty acids (EPA and DHA), and a decrease in serum omega-6 fatty acids (arachidonic acid). A FOLE may be the preferred lipid emulsion in patients with PN-cholestasis, dyslipidemia, or both. This trial is registered at clinicaltrials.gov as NCT00910104.

The role of parenteral lipids in the development of advanced intestinal failure-associated liver disease in infants: a multiple-variable analysis

BACKGROUND

Given the recent interest in the role of ω-6 lipids in the development of intestinal failure-associated liver disease (IFALD), the authors sought to examine the role of parenteral lipids in the development of a serum conjugated bilirubin >100 µmol/L (5.9 mg/dL; CB100) in infants.

METHOD

Between 2003 and 2004, data were collected prospectively on infants undergoing an abdominal surgical procedure. Univariate logistic regression models for the prediction of CB100 by 1 year postoperatively were developed. Predictors significant at the 0.2 level on univariate analysis were entered into a backward stepwise multiple variable logistic regression.

RESULTS

Of 152 infants who received parenteral nutrition (PN) postoperatively, 22 developed CB100. Predictors that met criteria for consideration in the multiple-variable model were age, weight, small bowel length, presence of a stoma, proportion of enteral feeds postoperatively, septic episodes, days of maximal PN amino acid (>2.5 g/kg/d), days of maximal lipid (>2.5 g/kg/d), and PN duration. The final model included septic episodes (odds ratio, 3.23; 95% confidence interval, 1.8-5.9) and days of lipid >2.5 g/kg/d (1.04; 1.003-1.06). At 60 days of maximal lipid, the odds of advanced IFALD were increased 10-fold.

CONCLUSIONS

This model suggests a key role of parenteral lipids and septic events in the development of CB100 from IFALD. These data may provide targets, such as careful line care, reduction in maximal lipid dose, or alternate lipids such as ω-3 fatty acids, to prevent CB100, an identified marker of subsequent liver failure from IFALD.

Neonatal short bowel syndrome

Neonatal short bowel syndrome is a disease with a high morbidity and mortality. The management of these patients is complex and requires a multidisciplinary approach. Recent advances in medical and surgical treatment options have improved outcomes. The following review highlights salient points in the management of this challenging patient population.

Comparison of 5 intravenous lipid emulsions and their effects on hepatic steatosis in a murine model

BACKGROUND

Plant-based intravenous lipid emulsions have been shown to contribute to parenteral nutrition-associated liver disease (PNALD). There is mounting evidence that fish oil-based emulsions may prevent this liver injury. This study compares 5 emulsions with different fat compositions and their effect on hepatic steatosis, one of the first hits in PNALD.

METHODS

C57BL/6J mice were placed on a fat-free diet and randomized into 5 equal groups. Each group received one of the commercially available intravenous lipid emulsions (Intralipid [Baxter/Fresenius Kabi, Deerfield, Ill], Liposyn II [Hospira Inc, Lake Forest, Ill], ClinOleic [Baxter/Clintec Parenteral SA, Cedex, France], SMOFlipid [Fresenius Kabi, Bad Homburg, Germany], or Omegaven [Fresenius Kabi Deutschland GmbH]) or normal saline. Liver enzymes, degree of steatosis, and fatty acid compositions were analyzed after 19 days.

RESULTS

Intralipid, Liposyn II, ClinOleic, and SMOFlipid groups all demonstrated moderate steatosis with hepatic fat contents of 17.4%, 21.9%, 22.5%, and 12.6%, respectively. Omegaven mice, however, had normal livers. Saline control mice developed biochemical evidence of essential fatty acid deficiency (EFAD). Lipid supplementation with Intralipid, Liposyn II, and Omegaven prevented the onset of biochemical EFAD, whereas administration of ClinOleic and SMOFlipid did not.

CONCLUSION

The fish oil-based lipid emulsion Omegaven prevented hepatic steatosis and EFAD in this murine model. ω-3 fatty acids may be efficacious in preventing PNALD and should be explored in the development of novel lipid emulsions.