Pediatric Smoflipid Therapy: Patient Response and Safety Concerns

Essential fatty acid deficiency in parenteral nutrition: Historical perspective and modern solutions, a narrative review

Essential fatty acid deficiency (EFAD) may occur in the setting of inadequate fat intake, malabsorption, malnutrition, and altered fat metabolism. Humans lack the enzymes to synthesize the essential acids linoleic acid and alpha-linolenic acid, so they must be obtained from the diet. Patients dependent on parenteral nutrition need adequate amounts of these essential fatty acids supplied in lipid injectable emulsions (ILEs). With the increasing use of multicomponent ILEs that are lower in linoleic and alpha-linolenic acid, it is imperative that clinicians understand appropriate dosing to prevent EFAD. An understanding of fatty acid composition and metabolic pathways is important, as the use of the Holman Index (triene:tetraene ratio) alone may lead to an inaccurate diagnosis of EFAD.

Nutritional Considerations in Neonates Requiring Gastrointestinal Surgery

Neonates who require gastrointestinal surgery are a complex group of patients that require special consideration with regard to nutritional supplementation and growth. During the acute postoperative phase, a major stress response causes catabolism with degradation of the body's nutrient stores leading to poor growth. Following surgery, parenteral nutrition is often required to support the surgical neonate; although, enteral nutrition, if feasible, is critical because it helps improve intestinal adaptation. However, the best type, mode, and duration of feeding is not established in the current literature. It is important to factor in the individual patient anatomy and site of intestinal resection when considering intestinal absorptive ability because these patients are at high risk for nutrient malabsorption, with the risk persisting even when enteral autonomy is achieved. The neonate undergoing gastrointestinal surgery requires close growth and nutritional monitoring both during the neonatal period but also into later life because risks of abnormalities persist. In this review, we summarize the impact of gastrointestinal surgery and postoperative intestinal changes on infant growth and nutrition.

Acquired Zinc Deficiency in Preterm Infant Post-Surgery for Necrotizing Enterocolitis (NEC) on Prolonged Total Parenteral Nutrition (TPN)

Zinc (Zn) is a vital trace element that plays a pivotal role in protein synthesis, cellular growth, and differentiation and is involved as a cofactor of metalloenzymes, performing a wide variety of metabolic, immune, and synthesis roles. Zn is required at all stages of an infant's and child's development, and severe Zn deficiency has been reported to lead to slower physical, cognitive, and sexual growth. Preterm neonates are at a higher risk of developing zinc deficiency for a variety of reasons, including low Zn intake from enteral feeds containing breast milk, relative malabsorption due to immaturity of the gastrointestinal tract with limited absorptive capacity, increased urinary loss of zinc, and increased demand during the early developmental stages. Moreover, premature infants are at risk of gastrointestinal diseases like necrotizing enterocolitis (NEC), which can limit absorption capacity and potentially lead to malabsorption. TPN is frequently used in preterm infants to provide them with sufficient nutrients and calories. However, it has its own complications, including cholestasis, especially if used for prolonged periods. In this case report, we are presenting the case of a male preterm infant who was delivered by caesarean section at 26 weeks' gestation. The baby developed an intestinal perforation due to NEC, for which he underwent surgery for resection of the necrotic bowel and the creation of a high ileal stoma and was put on prolonged total parenteral nutrition (TPN), which led to the development of zinc deficiency.

An Overview of Parenteral Nutrition from Birth to Adolescence Based on a Composite Fish Oil Containing Lipid Emulsion and a Pediatric Amino Acid Solution

Intestinal failure (IF) is characterized by a critical reduction in functional gut mass below the minimum needed for optimal growth in children. It requires parenteral nutrition (PN) and home-PN (HPN), which is challenging in terms of meeting nutritional needs according to age, growth velocity, clinical situation, and rapid changes in fluid and electrolyte requirements. Due to these complex requirements, age-adapted multi-chamber bags (MCBs) are important additions to the nutrition armamentarium. The launch of composite fish oil (FO)-containing intravenous lipid emulsions (ILEs) heralded the development of MCBs containing these ILEs in combination with a crystalline amino acid solution adapted for pediatric use. The safety and efficacy of lipid and amino acid components in this context have been widely documented in numerous published studies. This narrative manuscript includes a review of the articles published in PudMed, Embase, and Google Scholar up to June 2023 for the age groups of term infants to children and adolescents. Preterm infants with their highly specific demands are not included. It aims to offer an overview of the clinical experience regarding the use of a composite FO-based ILE and a developed specific amino acid solution.

In parenteral nutrition-fed piglets, fatty acids vary by lipid emulsion and tissue sampled

BACKGROUND

Children with intestinal failure without liver disease may be given soy-based lipid emulsion (SLE) or mixed lipid emulsion (MLE; containing soy, medium-chain triglyceride, olive, and/or fish oils). Both differ in essential fatty acid content: MLE has added arachidonic acid (AA) and docosahexaenoic acid (DHA). The aim of this study, in neonatal piglets, was to compare serum and tissue fatty acid composition when the emulsions were given at unrestricted doses.

METHODS

We compared SLE (n = 15) and MLE (n = 15) at doses of 10-15 g/kg/day in parenteral nutrition (PN). On day 14 we collected serum and tissues. Using gas-liquid chromatography, percentage fatty acids were measured in serum, brain, and liver phospholipid. Comparisons were made to reference values from litter-matched controls (n = 8).

RESULTS

Comparing median values, linoleic acid (LA) was lower for MLE vs SLE in serum (-27%), liver (-45%), and brain (-33%) (P < 0.001). AA was lower for MLE in serum (-25%), liver (-40%), and brain (-10%). DHA was higher for MLE in serum (+50%), liver (+200%), and brain (+10%). AA levels were lower for MLE vs control piglets in serum (-81%), liver (-63%), and brain (-9%). DHA levels were higher in serum (+41%), liver (+38%), and brain (+19%).

CONCLUSION

This study in piglets has shown that, at unrestricted doses, MLE treatment is associated with low serum and tissue AA compared with SLE and healthy litter-matched controls. Although not yet proven, low tissue AA levels may have functional consequences, and these data support current practice avoiding MLE dose restriction.

Composite lipid emulsion use and essential fatty acid deficiency in pediatric patients with intestinal failure with high parenteral nutrition dependence: A retrospective cohort study

BACKGROUND

Reports of essential fatty acid deficiency (EFAD) in patients receiving parenteral nutrition (PN) and a composite lipid (mixed oil intravenous lipid emulsion [MO ILE]) are predominantly when managed by lipid restriction. The objective of this study was to determine the prevalence of EFAD in patients with intestinal failure (IF) who are PN dependent without lipid restriction.

METHODS

We retrospectively evaluated patients, ages 0-17 years, followed by our intestinal rehabilitation program between November 2020 and June 2021 with PN dependency index (PNDI) of >80% on a MO ILE. Demographic data, PN composition, PN days, growth, and plasma fatty acid profile were collected. A plasma triene-tetraene (T:T) ratio >0.2 indicated EFAD. Summary statistics and Wilcoxon rank sum test evaluated to compare between PNDI category and ILE administration (grams/kilograms/day). P < 0.05 was considered significant.

RESULTS

Twenty-six patients (median age, 4.1 years [interquartile range (IQR) = 2.4-9.6]) were included. The median duration of PN was 1367 days (IQR = 824-3195). Sixteen patients had a PNDI of 80%-120% (61.5%). Fat intake for the group was 1.7 g/kg/day (IQR = 1.3-2.0). The median T:T ratio was 0.1 (IQR = 0.1-0.2) with no values >0.2. Linoleic and arachidonic acid were low in 85% and 19% of patients, respectively; however, Mead acid was normal in all patients.

CONCLUSION

This report is the largest to date on the EFA status of patients with IF on PN. These results suggest that, in the absence of lipid restriction, EFAD is not a concern when using MO ILEs in children receiving PN for IF.

Intestinal Failure-Associated Liver Disease and Growth Pre- and Post-Transition to a Composite Lipid Emulsion

OBJECTIVES

Infants with intestinal failure have an increased risk of intestinal failure-associated liver disease (IFALD). Composite intravenous lipid emulsion (ILE) may reduce the risk of cholestasis. The primary outcome was to compare IFALD rates in infants with intestinal failure, between those receiving a composite ILE versus soybean oil ILE. The secondary outcome compared growth between these 2 groups.

METHODS

At our 2 tertiary neonatal/pediatric hospitals, we identified all patients (≤1 year old) who received ≥6 weeks parenteral nutrition (PN) from 2010 to 2018. Data included liver and growth parameters. IFALD was defined as serum conjugated bilirubin (CB) >33 µmol/L (≥2 mg/dL). Nonparametric tests were used for all comparisons.

RESULTS

Fifty infants (35 composite ILE, 15 soybean oil ILE) were included. Those on composite ILE received PN for longer (10.1 vs 7.6 weeks; P = 0.001) and had higher baseline CB (29 vs 6.5 μmol/L; P = 0.001). No differences were found by 6 weeks (14.5 vs 5 μmol/L; P = 0.54) and by PN cessation (4 vs 4 μmol/L; P = 0.33). The proportion of patients with IFALD decreased from 54% to 20% for composite ILE, while stable given soybean oil ILE (7%). There were no differences in weight, length, or head circumference z scores ( P > 0.05).

CONCLUSIONS

In our institutions, over 8 years, chronic intestinal failure was rare. Composite ILE was the predominant lipid choice for infants who needed longer courses of PN or had developed cholestasis. Despite longer PN duration, and higher baseline CB, overall rates of IFALD decreased with composite ILE. Regardless of parenteral lipid used, there were no differences in growth.

Comparing mixed oil to soybean oil lipid emulsion in patients on home parenteral nutrition: a pilot prospective double-blind, crossover, randomized trial

BACKGROUND

Home parenteral nutrition (HPN) can be associated with increased liver enzymes, catheter-related bloodstream infections (CRBSI), and hospitalizations. Mixed oil (MO) versus soybean oil (SO) lipid emulsion reduces risks in hospitalized patients, but there are no randomized double-blinded controlled trials in HPN. Therefore, the primary objective was to test the study's feasibility such as recruitment and retention in the HPN population and the secondary objective was to assess changes in liver enzymes between MO and SO as well as other clinical and biochemical outcomes.

METHODS

This 13-month prospective double-blind crossover randomized pilot trial took place in Toronto, Canada. Participants were HPN patients who were a part of the HPN program at Toronto General Hospital. We recruited patients from the HPN program. HPN patients receiving SO were randomized to either MO or SO, and the study duration was 6 months in each arm (MO or SO) with a 1-month washout period resuming SO. As this is a crossover trial design, the patient is his/her own control. The main outcome measures were descriptions of study feasibility, namely the study recruitment and retention. We also collected biochemical parameters, CRSBI, hospitalization rate, antibiotic use, and mortality. Demographic, nutritional, clinical, and laboratory data were collected at baseline, 3 and 6 months of each arm. The primary analysis population was defined as the per-protocol population who completed the trial including all lipid measurements.

RESULTS

A total of 65 HPN patients were assessed, and 60 met the inclusion criteria for the study. Thirty-five percent (21/60) were randomized using a computer-generated random number sequence generator: 10 participants were randomized to receive SO first while 11 were randomized to receive MO first. At 13 months, 3/10 who received SO first completed the study, whereas 9/11 who received MO first completed the study. This did not meet our a priori criteria for success in recruitment and retention. Between types of lipid emulsions, there were no significant differences in changes in liver enzymes or biochemical and clinical outcomes, despite significant changes in plasma free fatty acid composition reflecting MO or SO.

CONCLUSIONS

Overall, this pilot trial demonstrated that the use of a prospective double-blind, crossover, randomized trial design was not feasible to conduct in the HPN population because of difficulties in recruiting and retaining patients. In addition, there was no significant impact of MO versus SO lipid emulsion on liver enzymes or most parameters. The lack of significance may be attributed to low sample size from low recruitment and high drop-out rate, short study duration (6 months/arm), and complex care. In a future definitive trial, a multicenter study of longer duration and a larger sample size is recommended, and drop-outs may be reduced by using a parallel study design.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02796833. Registered on 13 June 2016-retrospectively registered.

Lipid strategies to prevent intestinal failure-associated liver disease in neonates: A pilot trial

BACKGROUND

Intestinal failure-associated liver disease (IFALD) occurs in up to 50% of neonates treated with prolonged parenteral nutrition. Preventative strategies for IFALD include soybean oil lipid emulsion (SOLE) minimization and use of mixed-oil intravenous lipid emulsions (ILE). We conducted a pilot study prospectively comparing these two ILE strategies in the prevention of IFALD in neonates who required abdominal surgery.

METHODS

We randomized eligible neonates to SOLE at 1 g/kg/day (SOLE Min) or mixed-oil ILE containing fish oil (MOLE) at 3 g/kg/day. These treatment groups were also compared with historic controls who received SOLE at 2-3 g/kg/day (SOLE Historic). We defined IFALD as a direct bilirubin >2 mg/dl on two measurements. Secondary outcomes included laboratory, growth, clinical, and nutrition outcomes.

RESULTS

A total of 24 prospective and 24 historic patients were included. There was no difference in the rate of IFALD. However, there was a difference in the weekly change of direct bilirubin levels (SOLE Historic +0.293 mg/dl/week vs MOLE, P < 0.001; SOLE Min +0.242 mg/dl/week vs MOLE, P < 0.001). The MOLE group also had a lower direct bilirubin at study completion (SOLE Historic, 1.7 ± 1.7 mg/dl; SOLE Min, 1.6 ± 1.4 mg/dl; MOLE, 0.4 ± 0.4 mg/dl; P = 0.002) and received greater total calories (P = 0.008).

CONCLUSION

The rate of IFALD did not differ when comparing ILE strategies in neonates requiring abdominal surgery. However, the MOLE group maintained significantly lower direct bilirubin levels over time while receiving increased calories. This pilot study highlights the need for further randomized controlled trials comparing these ILE strategies.

Patterns of lipid-injectable emulsion use in neonatal intensive care units across the United States: A multi-institution survey

BACKGROUND

Lipid-injectable emulsions (ILEs) are a necessity for neonates dependent on parenteral nutrition (PN). In this manuscript, we describe the patterns of ILE use in neonatal intensive care units (NICUs) in the United States (US).

METHODS

An electronic survey was sent to 488 NICUs across the US between December 2020 and March 2021. Survey fields included availability and utilization of various ILE in neonates.

RESULTS

The response rate was 22% (107 out of 488). Soybean oil ILE (SO-ILE) and soybean oil, medium-chain triglycerides, olive oil, fish oil ILE (SO, MCT, OO, FO-ILE) had similar availability (87% vs 86%, respectively), and SO, MCT, OO, FO-ILE was more commonly used (SO-ILE, 71% vs SO, MCT, OO, FO-ILE, 86%). Fish oil-ILE (FO-ILE) was used by 55% of centers. SO-ILE was most frequently used with PN and needs <4 weeks without cholestasis (79%). The most common reason for SO, MCT, OO, FO-ILE use was cholestasis (71%). ILE minimization was used by 28% of SO-ILE and 22% of SO, MCT, OO, FO-ILE users; 95% of these centers restrict SO, MCT, OO, FO-ILE to doses ≤2 g/kg/day. Twenty-two percent of centers started FO-ILE at direct bilirubin of >5 mg/dl.

CONCLUSION

The results of this survey reveal significant variability in ILE usage across the US. Lipid minimization with SO, MCT, OO, FO-ILE and initiation of FO-ILE for cholestasis at higher bilirubin thresholds are prevalent. Such reports are crucial for a better understanding of ILE use in the NICU and in future ILE development.

Decreased liver damage in rat models of short bowel syndrome through DPP4 inhibition

PURPOSE

Total parenteral nutrition causes liver damage in patients with short bowel syndrome (SBS), in whom intestinal failure-associated liver disease (IFALD) is the strongest risk factor for mortality. We previously demonstrated the efficacy of dipeptidyl peptidase-4 inhibitors (DPP4-Is) for nutritional absorption and intestinal barrier function enhancement. Herein, we investigated the efficacy of DPP4-Is in preventing liver damage in SBS rat models.

METHODS

Rats were allocated to one of five groups: normal saline (NS) + sham, DPP4-I + sham, NS + SBS, DPP4-I + SBS, and GLP-2 + SBS. DPP4-I or NS was administered orally once daily. Serum aspartate aminotransferase, alanine aminotransferase (ALT), alkaline phosphatase, and total bile acid levels were measured to assess liver function. Moreover, we evaluated liver damage using the SAF (steatosis activity fibrosis) score, which is also used to assess nonalcoholic steatohepatitis.

RESULTS

ALT levels and SAF scores were significantly lower in the DPP4-I + SBS group than in the NS + SBS group. Jejunal and ileal villus heights were significantly higher in the DPP4-I + SBS group than in the GLP-2 + SBS group.

CONCLUSIONS

The downregulation of ALT levels and SAF scores triggered by DPP4-I use may be correlated with DPP4-I-induced adiposis inhibition in SBS and NASH models. Therefore, DPP4-I may be used to reduce IFALD in patients with SBS.

IFALD in children: What's new? A narrative review

Intestinal failure-associated liver disease (IFALD) is a progressive liver disease complicating intestinal failure (IF). It is a preventable and reversible condition, but at the same time, a potential cause of liver cirrhosis and an indication to combined or non-combined liver and small bowel transplantation. The diagnostic criteria are not yet standardized, so that its prevalence varies widely in the literature. Pathophysiology seems to be multifactorial, related to different aspects of intestinal failure and not only to the long-term parenteral nutrition treatment. The survival rates of children with IF have increased, so that the main problems today are preventing complications and ensuring a good quality of life. IFALD is one of the most important factors that limit long-term survival of patients with IF. For this reason, more and more interest is developing around it and the number of published articles is increasing rapidly. The purpose of this narrative review was to focus on the main aspects of the etiology, pathophysiology, management, prevention, and treatment of IFALD, based on what has been published mainly in the last 10 years. Controversies and current research gaps will be highlighted with the aim to pave the way for new project and high-quality clinical trials.

Intestinal failure-associated liver disease in the neonatal ICU: what we know and where we're going

PURPOSE OF REVIEW

Parenteral nutrition is an integral part of the care of infants in the neonatal ICU. However, prolonged use of parenteral nutrition can be associated with adverse outcomes, most notably parenteral nutrition-associated liver disease, now known as intestinal failure-associated liver disease (IFALD). This review highlights pertinent developments in the epidemiology of IFALD as it pertains to neonates and showcases recent advances in the pathophysiology, treatment, and outcomes of neonates with IFALD.

RECENT FINDINGS

The role of intravenous lipid emulsions in the pathogenesis, prevention, and treatment of IFALD remains a target for investigative studies. Recent data continues to support the use of fish-oil based intravenous lipids, but its use is limited due to concerns for essential fatty acid deficiency. Use of soy-based lipids and mixed lipids is not wrought with such concerns as these are often used at greater doses but their use is limited due to higher proinflammatory fatty acid content, increased phytosterols and decreased antioxidants, risk factors for the development of IFALD.

SUMMARY

Hepatic complications may limit the use of parenteral nutrition in the neonatal ICU. However, the pathophysiology of IFALD is continuing to be further elucidated and novel targets are being developed for the treatment of IFALD. As noninvasive disease monitoring strategies continue to be developed, early enteral nutrition ameliorates the risk of IFALD and should be considered when possible.