Association between two different lipid injectable emulsions and parenteral nutrition-associated cholestasis in very low birth weight infants: A retrospective cohort study

BACKGROUND

Using soybean oil-based lipid emulsions (Intralipid), which contain higher amounts of ω-6 fatty acids and phytosterols in parenteral nutrition, is a risk factor for cholestasis (parenteral nutrition-associated cholestasis [PNAC]). An alternative form of a mixed lipid emulsion (SMOFlipid) has been developed to reduce the risk of PNAC, but significant benefits over Intralipid in very low birth weight (VLBW) infants have yet to be demonstrated. The aim of this study was to compare the differences in PNAC incidence in VLBW infants receiving SMOFlipid vs Intralipid.

METHODS

The study was conducted in Sir Run Run Shaw Hospital of the Zhejiang University School of Medicine, Hangzhou, China, from January 2016 to March 2022. In total, 235 VLBW infants were administered SMOFlipid or Intralipid for ≥21 days and were included in the study. The primary outcome was the incidence of PNAC. Secondary outcomes included bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, late-onset sepsis, length of stay, weight 28 days after birth, severity of PNAC, and the time to reversal of PNAC.

RESULTS

Forty-four VLBW infants (35.5%) in the SMOFlipid group vs 41 (36.9%) in the Intralipid group achieved PNAC (P = 0.817). The subgroup analysis showed that the peak direct bilirubin level was lower (median [interquartile range] 55.6 [36.4] vs 118.4 [77.2] μmol/L; P < 0.001), and the time to reversal of PNAC was shorter (44 [49] vs 96 [61]; P < 0.001) in the SMOFlipid group than in the Intralipid group.

CONCLUSION

SMOFlipid may represent a better alternative for VLBW infants who require prolonged parenteral nutrition.

Modulation of secretory factors by lipofundin contributes to its anti‑neuroinflammatory effects

As the global population ages, the prevalence of neuroinflammatory diseases such as Alzheimer's disease, Parkinson's disease and stroke continues to increase. Therefore, it is necessary to develop preventive and therapeutic methods against neuroinflammatory diseases. Lipofundin is a lipid emulsion commonly used in clinical anesthetic solvents and nutritional supplements. Lipid emulsions have been shown to possess anti-inflammatory properties. However, the potential beneficial effect of lipofundin against neuroinflammation requires elucidation. In the present study, two cell models were used to investigate the efficacy of lipofundin against neuroinflammation. In the first model, BV2 mouse microglial cells were treated with lipopolysaccharide (LPS) to induce nitric oxide (NO) production as a model of neuroinflammation. In the second model, HMC3 human microglial were activated by LPS, and changes in the secretion of factors associated with inflammation were analyzed using Luminex xMAP® technology. Griess assay results revealed that lipofundin significantly prevented and treated LPS-induced NO production. An anti-neuroinflammatory effect was also observed in HMC3 cells, where lipofundin exhibited excellent preventive and therapeutic properties by reducing the LPS-induced expression and secretion of interleukin-1β. Notably, lipofundin also promoted the secretion of certain growth factors, suggesting a potential neuroprotective effect. These results demonstrate that, in addition to its role as a solvent for drugs and nutritional support, lipofundin may also have beneficial effects in alleviating the progression of neuroinflammation. These findings may serve as an important reference for future translational medicine applications.

Effect of different amino acid solutions on the oxidative stability of three different lipid emulsions in all-in-one admixtures

BACKGROUND AND AIM

Lipid peroxidation in parenteral nutrition mixtures is still a challenge. We aimed to evaluate the effect of two different amino acid solutions used in different clinical situations on lipid peroxidation of three different lipid emulsions (Intralipid®, ClinOleic® and SMOFlipid®) in all-in-one admixtures during 24 hours of simulated infusion. The selected amino acid solutions included one used in stable patients and one used in renal insufficiency (Aminomel10E® and Nephrotect®, respectively).

METHODS

Eighteen all-in-one admixtures were prepared. The simulated infusion with light protection was conducted straight after the preparation for 24 hours at room temperature. The lipid peroxidation process was evaluated in all-in-one admixtures and the original lipid emulsion by determining the malondialdehyde levels (HPLC) and conjugated dienes and trienes (spectrophotometry: UV-vis).

RESULTS

Malondialdehyde in the original packaging was lower in SMOFlipid® (9 µM) compared to Intralipid® (27 µM, p=0.0003) and ClinOleic® (25 µM, p=0.0001). During simulated infusion, Clinoleic® showed a significantly lower rate of lipid peroxidation (26% decrease in aldehyde levels) in comparison to Intralipid® and SMOFlipid® (up to 39% and 31% increase in aldehyde levels, respectively) when the admixture was based on Aminomel10E®. In admixtures based on Nephrotect®, Clinoleic® and SMOFlipid® showed better oxidative stability in comparison to Intralipid. Admixtures based on Nephrotect® and Intralipid had higher levels of primary lipid peroxidation products than those based on Clinoleic® (p=0.030) or SMOFlipid® (p=0.071, NS).

CONCLUSIONS

Amino acid solutions influence the rate of lipid peroxidation. The observation should be confirmed in larger studies with different amino acid solutions. This article is protected by copyright. All rights reserved.

Sodium bicarbonate reverts electrophysiologic cardiotoxicity of ropivacaine faster than lipid emulsions in a porcine model

Ropivacaine has been described as a safer local anaesthetic (LA); however, serious cardiotoxic accidents have been reported. Intravenous-lipid-emulsion (ILE) therapy during LA intoxication seems to act as an antidote. Sodium bicarbonate is the standard treatment for sodium channel blocker drug toxicity. We compared both antidotes on the reversion of electrophysiologic toxicity induced by ropivacaine. Ropivacaine 5 mg kg^-1 was administered in 24 pigs, and 3 min later, the animals received ILE: 1.5 ml kg^-1  + 0.25 ml kg^-1  min^-1 (ILE group); sodium bicarbonate: 2 mEq kg^-1  + 1 mEq kg^-1  h^-1 (NaHCO₃ group); saline solution (CTL group). Electrophysiological parameters were evaluated for 30 min. The area under the curve (AUC) for the first 5 or 30 min was compared between groups. Ropivacaine induced a lengthening of the PR interval by 17% (P = 0.0001), His-ventricle-interval by 58% (P = 0.001), sinus QRS complex by 56% (P = 0.0001), paced QRS at 150 bpm by 257% (P = 0.0001), and at 120 bpm by 143% (P = 0.0001) in all groups. At 5 min after treatment, sinus QRS in the NaHCO₃ group was shorter than that in the CTL group (AUC_QRS5 , P = 0.003) or ILE group (AUC_QRS5 , P = 0.045). During the first minute, seven of the animals in the NaHCO₃ group vs. two in the ILE or 0 in the CTL group recovered more than 30% of the sinus QRS previously lengthened by ropivacaine (P = 0.003). Sodium bicarbonate reversed the electrophysiological toxicity of ropivacaine faster than ILE and control groups.

Effects of intravenous lipid emulsions on the reversal of pacing-induced ventricular arrhythmias and electrophysiological alterations in an animal model of ropivacaine toxicity

INTRODUCTION

Ropivacaine is considered to have a wider margin of cardiovascular safety. However, several reports of ventricular arrhythmias (VA) due to ropivacaine toxicity have been documented. Intravenous lipid emulsions (ILEs) have recently been used successfully in the treatment of local anesthetic intoxication. The main objective of the present study was to evaluate the efficacy of the ILEs in the prevention of pacing-induced-VA and electrophysiological alterations in an animal model of ropivacaine toxicity.

METHODS

Nineteen pigs were anesthetized and instrumentalized. A baseline programmed electrical ventricular stimulation protocol (PEVSP) to induce VA was performed. Ropivacaine (5 mg·kg^-1 + 100 μg·kg^-1·min^-1) followed by normal saline infusion (control group n = 8) or intralipid 20% (1.5 mL·kg^-1 + 0.25 mL·kg^-1·min^-1) for the ILE group (n = 8), were administered three minutes after the ropivacaine bolus. PEVSP was repeated 25 min after the onset of ropivacaine infusion. Pacing-induced VA and electrophysiological abnormalities were assessed in both groups. A sham-control group (n = 3) without ropivacaine infusion was included.

RESULTS

Most of the electrophysiological parameters evaluated were affected by ropivacaine: PR interval by 28% (p = 0.001), AV interval by 40% (p = 0.001), sinus QRS by 101% (p = 0.001), paced QRS at a rate of 150 bpm by 258% (p = 0.001), and at 120 bpm by 241% (p = 0.001). Seven animals (87.5%) in the control group and eight animals (100%) in the ILE group developed sustained-VA (p = 0.30). Successful resuscitation occurred in 100% of animals in the ILE group vs. 57% of animals in the control group, p = 0.038. Pacing-induced-VA terminated at the first defibrillation attempt in 75% of the animals in the ILE group vs. 0% in the control group, p = 0.01.

CONCLUSION

Ropivacaine strongly altered the parameters of ventricular conduction, thus facilitating the induction of VA. ILEs did not prevent pacing-induced VA. However, facilitated resuscitation and termination of VA were delivered at the first defibrillation attempt compared to the control group.

Lipid Nanocarriers for Anti-HIV Therapeutics: A Focus on Physicochemical Properties and Biotechnological Advances

Since HIV was first identified, and in a relatively short period of time, AIDS has become one of the most devastating infectious diseases of the 21st century. Classical antiretroviral therapies were a major step forward in disease treatment options, significantly improving the survival rates of HIV-infected individuals. Even though these therapies have greatly improved HIV clinical outcomes, antiretrovirals (ARV) feature biopharmaceutic and pharmacokinetic problems such as poor aqueous solubility, short half-life, and poor penetration into HIV reservoir sites, which contribute to the suboptimal efficacy of these regimens. To overcome some of these issues, novel nanotechnology-based strategies for ARV delivery towards HIV viral reservoirs have been proposed. The current review is focused on the benefits of using lipid-based nanocarriers for tuning the physicochemical properties of ARV to overcome biological barriers upon administration. Furthermore, a correlation between these properties and the potential therapeutic outcomes has been established. Biotechnological advancements using lipid nanocarriers for RNA interference (RNAi) delivery for the treatment of HIV infections were also discussed.

Use of Intravenous Lipid Emulsions With Parenteral Nutrition: Practical Handling Aspects

A number of topics important to the handling of intravenous lipid emulsions (ILEs) were discussed at the international summit. ILE handling includes the preparation and the administration steps in the typical use of parenteral nutrition (PN). The discussion and consensus statements addressed several issues, including standardization of the PN process, use of commercially available multi-chamber PN or compounded PN bags, the supervision by a pharmacist with expertise, limiting ILE repackaging, and infusion duration.

Lipid emulsion therapy in women with recurrent pregnancy loss and repeated implantation failure: The role of abnormal natural killer cell activity

Altered immune and/or inflammatory response plays an important role in cases of recurrent pregnancy loss (RPL) and repeated implantation failure (RIF). Exacerbation of the maternal immune response through increased NK cell activity and inflammatory cytokines can cause embryo rejection leading to abortion or embryo implantation failure. Immunosuppressors or immunomodulators can help or prevent this condition. Currently, lipid emulsion therapy (LET) has emerged as a treatment for RPL and RIF in women with abnormal NK cell activity, by decreasing the exacerbated immune response of the maternal uterus and providing a more receptive environment for the embryo. However, the mechanisms by which the intralipid acts to reduce NK cell activity are still unclear. In this review, we focus on the studies that conducted LET to treat patients with RPL and RIF with abnormal NK cell activity. We find that although some authors recommend LET as an effective intervention, more studies are necessary to confirm its effectiveness in restoring NK cell activity to normal levels and to comprehend the underlying mechanisms of the lipids action in ameliorating the maternal environment and improving the pregnancy rate.

Impact of Parenteral Lipid Emulsion Components on Cholestatic Liver Disease in Neonates

Total parenteral nutrition (TPN) is a life-saving intervention for infants that are unable to feed by mouth. Infants that remain on TPN for extended periods of time are at risk for the development of liver injury in the form of parenteral nutrition associated cholestasis (PNAC). Current research suggests the lipid component of TPN is a factor in the development of PNAC. Most notably, the fatty acid composition, vitamin E concentration, and presence of phytosterols are believed key mediators of lipid emulsion driven PNAC development. New emulsions comprised of fish oil and medium chain triglycerides show promise for reducing the incidence of PNAC in infants. In this review we will cover the current clinical studies on the benefit of fish oil and medium chain triglyceride containing lipid emulsions on the development of PNAC, the current constituents of lipid emulsions that may modulate the prevalence of PNAC, and potential new supplements to TPN to further reduce the incidence of PNAC.

Clinical application of fish-oil intravenous lipid emulsion in adult home parenteral nutrition patients

BACKGROUND

High-ω-6 polyunsaturated fatty acids (PUFAs) are noted to contribute to development of intestinal failure-associated liver disease (IFALD) in home parenteral nutrition (HPN). Fish oil (FO) has been added to latest generation of lipid injectable emulsion (ILE) to increase ω-3:ω-6 PUFA ratio; however, appropriate dose of FO to treat IFALD is unknown.

METHODS

After approval of exclusive FO ILE in the US for pediatric patients, we noted 2 adult patients with ongoing IFALD despite transition to mixed-oil (MO) ILE. They were transitioned to off-label FO ILE after review of literature regarding use of FO ILE in adult HPN patients was conducted to guide management.

RESULTS

The first case involves a 40-year-old female receiving HPN with IFALD refractory to MO ILE. MO ILE (with 15% FO) was provided at 50 g/d for 3 d/wk and combined with FO ILE at 50 g/d for 4 d/wk. This combination resulted in improvement in liver studies and allowed for decrease in dextrose calories. The second case involves a 49-year-old male receiving HPN (secondary to complications of necrotizing pancreatitis) who developed IFALD. FO ILE was used as the sole source of lipids and led to improvement in liver function tests. No evidence of essential fatty acid deficiency was found in either case.

CONCLUSIONS

Current case presentations and review of literature support the use of FO ILE to increase ω-3 PUFAs in patients with IFALD refractory to MO ILE. Additional research is necessary to delineate the dose of FO ILE necessary to achieve benefit.

High Dose Intravenous Fish Oil Reduces Inflammation-A Retrospective Tale from Two Centers

AIM

Patients on parenteral nutrition (PN) are prone to inflammation. This may aggravate an existing proinflammatory state and become a critical factor in the development of liver dysfunction (LD). Intravenous fish oil may attenuate this inflammatory state, but data on its use in adults are scarce. The aim of this study was to investigate the effects of adding a pure fish oil intravenous lipid emulsion (ILE) into short- and long-term PN in patients either at risk of, or with existing, inflammation.

METHODS

A retrospective analysis of 61 patients (32 female, 29 male, mean age 51.5 ± 12.6 years) who received all-in-one PN, including amino acids, glucose, and lipids supplemented with pure fish oil ILE, was performed. Pure fish oil ILE (Omegaven®, Fresenius Kabi, Bad Homburg, Germany) was used along with the standard ILE to reach a fish oil dose of 0.4-0.5 g fish oil/kg/d. Diagnoses were chronic intestinal failure (CIF, n = 20), Crohn's disease (CD, n = 22), and ulcerative colitis (UC, n = 19). The observation period was 12 months for CIF and 21 days for UC and CD.

RESULTS

A reduction in inflammation was noticeable in all patients and became statistically significant in CD (hsCRP p < 0.0001, ESR p = 0.0034, procalcitonin p = 0.0014, Il-6 p = 0.001) and UC groups (hsCRP and ESR p < 0.0001, Il-6 p = 0.0001, TNF-α p = 0.0113). In the CIF group, the total bilirubin concentration (p = 0.2157) and aspartate transaminase SGOT (p = 0.1785) did not vary over time.

CONCLUSIONS

PN with pure fish oil ILE reduces some inflammatory parameters in IBD and maintains liver function parameters in CIF patients. Fish oil might become a valuable ingredient in both short- and long-term PN in patients at risk of liver dysfunction.

Yew poisoning - pathophysiology, clinical picture, management and perspective of fat emulsion utilization

The article presents pathophysiology, clinical picture and management of yew poisoning. Authors present also their own experiences with treating yew poisoning with fat emulsion. Plants of the yew genus, of which in Europe predominates Taxus baccata, are well known for their toxic properties. Particularly high concentrations of poisonous alkaloids are present in the needles of this evergreen and highly popular decorative plant. The danger associated with accidental or intentional ingestion of yew is primarily related to the cardiotoxic effects of the alkaloids (taxine A and B). Taxine B shows a much stronger toxic effect on the heart than taxine A. It affects atrio-ventricular conduction, what may result in a widening of the QRS complexes, atrio-ventricular blocks (A-V) of II/III degree and even in asystole. Yew poisoning is relative rare and evidence-based treatment guidelines on management of such poisoning is hard to prepare. The first-line treatement should base on suportive therapy. In some cases extracorporeal life support therapies such veno-arterial ECMO should be consider. There are also premise based on case reports and mechanism of action that the use of fat emulsion may be effective rescue treatment.

Composition and Functionality of Lipid Emulsions in Parenteral Nutrition: Examining Evidence in Clinical Applications

Lipid emulsions (LEs), an integral component in parenteral nutrition (PN) feeding, have shifted from the primary aim of delivering non-protein calories and essential fatty acids to defined therapeutic outcomes such as reducing inflammation, and improving metabolic and clinical outcomes. Use of LEs in PN for surgical and critically ill patients is particularly well established, and there is enough literature assigning therapeutic and adverse effects to specific LEs. This narrative review contrarily puts into perspective the fatty acid compositional (FAC) nature of LE formulations, and discusses clinical applications and outcomes according to the biological function and structural functionality of fatty acids and co-factors such as phytosterols, α-tocopherol, emulsifiers and vitamin K. In addition to soybean oil-based LEs, this review covers clinical studies using the alternate LEs that incorporates physical mixtures combining medium- and long-chain triglycerides or structured triglycerides or the unusual olive oil or fish oil. The Jaded score was applied to assess the quality of these studies, and we report outcomes categorized as per immuno-inflammatory, nutritional, clinical, and cellular level FAC changes. It appears that the FAC nature of LEs is the primary determinant of desired clinical outcomes, and we conclude that one type of LE alone cannot be uniformly applied to patient care.

Lipid Emulsion Therapies and Type 1 Hypersensitivity Reactions: Risk Assessment and Management

Over the past decades, awareness and attention given to food allergies has extended further into the realm of pharmacotherapy. Despite the presence of similar ingredients, different intravenous lipid emulsion (ILE)-based medication products have a wide variety of warnings and contraindications for patients with food allergies. Only limited literature is available to guide clinicians in making appropriate medication therapy adjustments to reduce the risk of hypersensitivity reactions in atopic patient populations. Therefore, the authors sought to develop a comprehensive review of potential risk factors or approaches for management of patients with atopic history and need for ILE therapy. Through thorough review of available literature published worldwide, a description of potential contraindications, risk factors, and evaluation methods is presented. Although the current state of knowledge remains relatively poor, this review aims to provide clinicians a better understanding of which risk factors related to the development of hypersensitivity reactions are relevant to lipid emulsion products and how to best manage patients who may be at risk for severe reaction based on their history. Evaluating personal atopic history is essential to the development of an appropriate risk classification system and approaching an individual's therapeutic options. By applying this assessment to local populations, providers should be able to develop an institutional guideline for screening and minimizing risk of substantial hypersensitivity reactions. Finally, a brief review of methods for managing type 1 hypersensitivity reactions is provided in the event that a breakthrough reaction does occur.

Disparate Candida albicans Biofilm Formation in Clinical Lipid Emulsions Due to Capric Acid-Mediated Inhibition

Receipt of parenteral nutrition (PN) remains an independent risk factor for developing catheter-related bloodstream infections (CR-BSI) caused by fungi, including by the polymorphic fungus Candida albicans, which is notoriously adept at forming drug-resistant biofilm structures. Among a variety of macronutrients, PN solutions contain lipid emulsions to supply daily essential fats and are often delivered via central venous catheters (CVCs). Therefore, using an in vitro biofilm model system, we sought to determine whether various clinical lipid emulsions differentially impacted biofilm growth in C. albicans We observed that the lipid emulsions Intralipid and Omegaven both stimulated C. albicans biofilm formation during growth in minimal medium or a macronutrient PN solution. Conversely, Smoflipid inhibited C. albicans biofilm formation by approximately 50%. Follow-up studies revealed that while Smoflipid did not impair C. albicans growth, it did significantly inhibit hypha formation and hyphal elongation. Moreover, growth inhibition could be recapitulated in Intralipid when supplemented with capric acid-a fatty acid present in Smoflipid but absent in Intralipid. Capric acid was also found to dose dependently inhibit C. albicans biofilm formation in PN solutions. This is the first study to directly compare different clinical lipid emulsions for their capacity to affect C. albicans biofilm growth. Results derived from this study necessitate further research regarding different lipid emulsions and rates of fungus-associated CR-BSIs.

An Observational Study of Smoflipid vs Intralipid on the Evolution of Intestinal Failure-Associated Liver Disease in Infants With Intestinal Failure

BACKGROUND

SMOFlipid has a more diverse lipid profile than traditional Intralipid and has become the standard lipid for patients in our intestinal rehabilitation program. Our objective was to compare outcomes in neonates with intestinal failure (IF) who received SMOFlipid against those receiving Intralipid.

METHODS

This was a retrospective cohort study of infants with IF with a minimum follow-up of 12 months in 2008-2016. Patients were stratified into 2 groups: group 1 received SMOFlipid; group 2 was a historical cohort who received Intralipid. The primary outcome was liver function evaluated using conjugated bilirubin (CB) levels. Statistical analysis included the Mann-Whitney U and χ² tests, with an α value < 0.05 considered significant. Approval was obtained from our institutional review board.

RESULTS

Thirty-seven patients were evaluated (17 = SMOFlipid, 20 = Intralipid). SMOFlipid patients were less likely to reach CB of 34 (24% vs 55%, P = 0.05), 50 µmol/L (11.8% vs 45%; P = 0.028), and did not require Omegaven (0% vs 30%; P = 0.014). CB level at 3 months after initiation of parenteral nutrition (PN) was lower in patients receiving SMOFlipid (0 vs 36 µmol/L; P = 0.01). Weight z-scores were improved for patients receiving SMOFlipid at 3 months (-0.932 vs -2.092; P = 0.028) and 6 months (-0.633 vs -1.614; P = 0.018). There were no differences in PN-supported patients or demographics between the groups.

CONCLUSION

Use of SMOFlipid resulted in decreased development of IF-associated liver disease in patients with IF when assessed using biochemical tests.

Heart Rate Variability: A Potential Tool for Monitoring Immunomodulatory Effects of Parenteral Fish Oil Feeding in Patients With Sepsis

Fish oil, rich in the very-long chain omega (ω)-3 polyunsaturated fatty acids (PUFAs), has been found to have immunomodulatory effects in different groups of critically ill patients. In addition, its parenteral administration seems to attenuate the inflammatory response within 2 to 3 days. The activation of the cholinergic anti-inflammatory pathway has been suggested to mediate such immunoregulatory effects. As different experimental studies have convincingly illustrated that enhanced vagal tone can decrease pro-inflammatory cytokine secretion, novel monitoring tools of its activity at the bedside could be developed, to evaluate nutritional manipulation of immune response in the critically ill. Heart rate variability (HRV) is the variability of R-R series in the electrocardiogram and could be a promising surrogate marker of immune response and its modulation during fish oil feeding, rich in ω-3 PUFAs. Heart rate variability is an indirect measure of autonomic nervous system (ANS) output, reflecting mainly fluctuations in ANS activity. Through HRV analysis, different "physiomarkers" can be estimated that could be used as early and more accurate "smart alarms" because they are based on high-frequency measurements and are much more easy to get at the bedside. On the contrary, various "biomarkers" such as cytokines exhibit marked interdependence, pleiotropy, and their plasma concentrations fluctuate from day to day in patients with sepsis. In this respect, an inverse relation between different HRV components and inflammatory biomarkers has been observed in patients with severe sepsis and septic shock, whereas a beneficial effect of ω-3 PUFAs on HRV has been demonstrated in patients with cardiovascular diseases. Consequently, in this article, we suggest that a beneficial effect of ω-3 PUFAs on HRV and clinical outcome in patients with sepsis merits further investigation and could be tested in future clinical trials as a real-time monitoring tool of nutritional manipulation of the inflammatory response in the critically ill.

Biological and Clinical Aspects of an Olive Oil-Based Lipid Emulsion-A Review

Intravenous lipid emulsions (ILEs) have been an integral component of parenteral nutrition for more than 50 years. Numerous formulations are available and are based on vegetable (soybean, olive, coconut) and animal (fish) oils. Therefore, each of these formulations has a unique fatty acid composition that offers both benefits and limitations. As clinical experience and our understanding of the effects of fatty acids on various physiological processes has grown, there is evidence to suggest that some ILEs may have benefits compared with others. Current evidence suggests that olive oil-based ILE may preserve immune, hepatobiliary, and endothelial cell function, and may reduce lipid peroxidation and plasma lipid levels. There is good evidence from a large randomized controlled study to support a benefit of olive oil-based ILE over soybean oil-based ILE on reducing infections in critically ill patients. At present there is limited evidence to demonstrate a benefit of olive oil-based ILE over other ILEs on glucose metabolism, and few data exist to demonstrate a benefit on clinical outcomes such as hospital or intensive care unit stay, duration of mechanical ventilation, or mortality. We review the current research and clinical evidence supporting the potential positive biological and clinical aspects of olive oil-based ILE and conclude that olive oil-based ILE is well tolerated and provides effective nutritional support to various PN-requiring patient populations. Olive oil-based ILE appears to support the innate immune system, is associated with fewer infections, induces less lipid peroxidation, and is not associated with increased hepatobiliary or lipid disturbances. These data would suggest that olive oil-based ILE is a valuable option in various PN-requiring patient populations.

Children With Intestinal Failure Undergoing Intestinal Rehabilitation Are at Risk for Essential Fatty Acid Deficiency

BACKGROUND

Essential fatty acid (EFA) status may be compromised during the intestinal failure (IF) rehabilitation. Parenteral lipid restriction is used to treat intestinal failure associated liver disease (IFALD), while the enteral fatty acid (FA) absorption remains limited. We analyzed the FA status among pediatric IF and intestinal insufficiency patients.

METHODS

We evaluated 49 patients aged 0-18 years attending our nationwide IF referral center. Their serum FA fractions were determined and examined against previous nutrition, parenteral lipid emulsion, and intestinal anatomy data. The patients were divided into 3 subgroups according to their dependence on parenteral nutrition (PN): full enteral (EN) (n = 33), supplemental PN (n = 14) or predominantly PN (n = 20). Trien:tetraen ratio (TTR) ≥0.2 was considered diagnostic for essential fatty acid deficiency (EFAD) and increased risk was suspected if TTR exceeded 0.1.

RESULTS

We identified 8 (16%) patients with elevated TTR ≥0.1; in 3 of them the ratio exceeded 0.2. Five of these children belonged to supplemental PN group. This group carried the highest incidence of elevated TTR (P = 0.0016), with median TTR at 0.06 (interquartile range 0.03-0.09) and two-thirds of the analyzed TTR ≥0.5. Increased EFAD risk was associated with young age (P = 0.0291), current PN with low parenteral lipid content (P = 0.0003), and short remaining small bowel (P = 0.0013).

CONCLUSIONS

IF children with supplemental PN carry the highest overall risk for EFAD. Young age, current PN, and short remaining small bowel also increase the risk for EFAD.

Fish Oil-Containing Lipid Emulsions in Adult Parenteral Nutrition: A Review of the Evidence

BACKGROUND

There is evidence from laboratory and animal studies that fish oil-containing intravenous lipid emulsions (FOC-IVLEs) have a beneficial effect on inflammation and the immune response, suggesting a possible clinical benefit. Clinical studies of FOC-IVLEs have reported mixed results. The aim of this review is to present findings from recent randomized controlled clinical trials and other quality clinical studies investigating the effects of administering intravenous fish oil alone or as part of a multilipid emulsion and to examine the quality of these studies in an objective, evidence-based manner.

METHODS

Studies comparing FOC-IVLEs with other IVLEs in adults were included. Thirty-four clinical studies were evaluated: 19 investigated levels of inflammatory and immune markers as an endpoint; 13 investigated rates of infection or sepsis; 3 investigated clinical outcomes in septic patients; and 29 investigated general clinical outcomes.

RESULTS

There was conflicting evidence for a beneficial effect of fish oil on levels of inflammatory and immune markers and some evidence that fish oil decreased the rate of postoperative atrial fibrillation. Studies generally reported few statistical differences in clinical outcomes and rates of infection and sepsis with FOC-IVLEs as compared with other IVLEs. The quality of reporting was generally poor, and the presented evidence for comparisons between FOC-IVLEs and other IVLEs was inconclusive or weak.

CONCLUSIONS

There is very little high-quality evidence that FOC-IVLEs have a more beneficial effect than other IVLEs on clinical outcomes in adult patients.

Efficient co-delivery of immiscible hydrophilic/hydrophobic chemotherapeutics by lipid emulsions for improved treatment of cancer

Combinational nanomedicine is becoming a topic of much interest in cancer therapy, although its translation into the clinic remains extremely challenging. One of the main obstacles lies in the difficulty to efficiently co-deliver immiscible hydrophilic/hydrophobic drugs into tumor sites. The aim of this study was to develop co-loaded lipid emulsions (LEs) to co-deliver immiscible hydrophilic/hydrophobic drugs to improve cancer therapy and to explore the co-delivery abilities between co-loaded LEs and mixture formulation. Multiple oxaliplatin/irinotecan drug–phospholipid complexes (DPCs) were formulated. Co-loaded LEs were prepared using DPC technique to efficiently encapsulate both drugs. Co-loaded LEs exhibited uniform particle size distribution, desired stability and synchronous release profiles in both drugs. Co-loaded LEs demonstrated superior anti-tumor activity compared with the simple solution mixture and the mixture of single-loaded LEs. Furthermore, co-loaded nanocarriers could co-deliver both drugs into the same cells more efficiently and exhibited the optimized synergistic effect. These results indicate that co-loaded LEs could be a desired formulation for enhanced cancer therapy with potential application prospects. The comparison between co-loaded LEs and mixture formulation is significant for pharmaceutical designs aimed at co-delivery of multiple drugs.

Omega-3 Fatty Acids in Modern Parenteral Nutrition: A Review of the Current Evidence

Intravenous lipid emulsions are an essential component of parenteral nutrition regimens. Originally employed as an efficient non-glucose energy source to reduce the adverse effects of high glucose intake and provide essential fatty acids, lipid emulsions have assumed a larger therapeutic role due to research demonstrating the effects of omega-3 and omega-6 polyunsaturated fatty acids (PUFA) on key metabolic functions, including inflammatory and immune response, coagulation, and cell signaling. Indeed, emerging evidence suggests that the effects of omega-3 PUFA on inflammation and immune response result in meaningful therapeutic benefits in surgical, cancer, and critically ill patients as well as patients requiring long-term parenteral nutrition. The present review provides an overview of the mechanisms of action through which omega-3 and omega-6 PUFA modulate the immune-inflammatory response and summarizes the current body of evidence regarding the clinical and pharmacoeconomic benefits of intravenous n-3 fatty acid-containing lipid emulsions in patients requiring parenteral nutrition.

Lipid emulsions in the treatment and prevention of parenteral nutrition-associated liver disease in infants and children

Long-term parenteral nutrition (PN) carries the risk of progressive liver disease in infants with intestinal failure. Although PN-associated liver disease (PNALD) is multifactorial in etiology, components of soybean oil lipid emulsions have been implicated in the disease's pathogenesis. Historically, infants with PNALD who were unable to wean from PN to full enteral feeding developed cirrhosis and end-stage liver disease, which require liver transplantation to survive. Over the past 2 decades, novel strategies for the management of parenteral lipids have improved morbidity and mortality from PNALD in infants with intestinal failure. Current strategies for the treatment of PNALD include restricting the dose of parenteral soybean oil lipid emulsion and/or replacing the soybean oil with a parenteral fish-oil lipid emulsion or emulsions of mixed-lipid sources. The purpose of this report is to review published data that evaluate these strategies in parenteral lipid management for the treatment and prevention of PNALD.

Successful management of aluminium phosphide poisoning using intravenous lipid emulsion: Report of two cases

Aluminum phosphide (ALP) is a cheap, easily available agricultural pesticide which causes lethal poisoning by liberation of phosphine and inhibition of cytochrome c oxidase thereby leading to cellular hypoxia. Although there is no known specific antidote, clinical trials are still going on. We present here two cases of ALP poisoning who were successfully managed by treatment with lipid emulsion and intravenous magnesium sulfate.

Changes in Antioxidant Defense System Using Different Lipid Emulsions in Parenteral Nutrition in Children after Hematopoietic Stem Cell Transplantation

Background: Traditionally, lipids used in parenteral nutrition (PN) are based on ω-6 fatty acid-rich vegetable oils, such as soybean oil, with potential adverse effects involving oxidative stress. Methods: We evaluated the antioxidant defense system in children, after hematopoietic stem cell transplantation (HSCT), who were randomized to use a lipid emulsion with fish oil or soybean oil. Blood samples at baseline, at 10 days, and at the end of the PN were taken to analyze plasma retinol, α-tocopherol, β-carotene, coenzyme Q9 and coenzyme Q10 levels, and catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPOX), and superoxide dismutase (SOD) levels in lysed erythrocytes. Results: An increase in plasma α-tocopherol levels in the group of patients receiving the fish oil-containing emulsion (FO) compared with the group receiving the soybean emulsion was observed at day 10 of PN. Concurrently, plasma α-tocopherol increased in the FO group and β-carotene decreased in both groups at day 10 compared with baseline levels, being more significant in the group receiving the FO emulsion. Conclusion: FO-containing emulsions in PN could improve the antioxidant profile by increasing levels of α-tocopherol in children after HSCT who are at higher risk of suffering oxidative stress and metabolic disorders.

Controlling the enzymatic digestion of lipids using hybrid nanostructured materials

Solid nanoparticle-lipid hybrids have been engineered by using spray drying to assemble monodisperse hydrophilic silica nanoparticles and submicron lipid (triglyceride) emulsions together into composite microparticles, which have specific activity toward enzymes. The influence of silica particle size (100-1000 nm) and emulsifier type (anionic and cationic) on the three-dimensional structure of the composite particles was investigated. The nanostructure of the hybrid particles, which is controlled by the size of the voids between the closely packed silica particles, plays a critical role in lipase action and hence lipid digestion kinetics. Confining lipid droplets within the nanostructured silica aggregates led to 2- to 15-fold enhanced rate of lipolysis in comparison with dispersed coarse oil droplets. The composite particles were tailored to enhance, retain or sustain the lipolysis kinetics of submicron lipid emulsions. The presence of repulsive nanoparticle-droplet interactions favored aqueous redispersion and fast lipolysis of the hybrid composite materials, while attractive interactions hindered redispersion and delayed lipolysis of the confined lipid droplets. Such hybrid nanomaterials can be exploited to control the gastrointestinal enzymatic action and promisingly form the basis for the next generation of foods and medicines.

Distribution of Tocopherols and Tocotrienols in Guinea Pig Tissues Following Parenteral Lipid Emulsion Infusion

BACKGROUND

Tocopherols and tocotrienols possess vitamin E activity and function as the major lipid-soluble antioxidants in the human body. Commercial lipid emulsions are composed of different oils and supply different amounts of vitamin E. The objective of this study was to measure all 8 vitamin E homologs within 4 different commercial lipid emulsions and evaluate their distribution in guinea pig tissues.

MATERIALS AND METHODS

The distribution of vitamin E homologs within plasma and guinea pig tissues was determined using a high-performance liquid chromatography (HPLC) system. Lipid hydroperoxides in lipid emulsions were determined using a commercial kit (Cayman Chemical Company, Ann Arbor, MI), and malondialdehyde tissue levels were determined using an HPLC system.

RESULTS

The lipid emulsions contained variable amounts of tocopherols, which were significantly different between emulsions. Tocotrienols were present at very low concentrations (≤0.3%). We found no correlation between the amount of vitamin E present in the lipid emulsions and lipid peroxidation. Hydroperoxides were the lowest with an olive oil-based emulsion and highest with a fish oil emulsion. The predominant vitamin E homolog in guinea pig tissues was α-tocopherol. No tissues had detectable levels of tocotrienols. Vitamin E levels (primarily α-tocopherol and γ-tocopherol) were highly variable among organ tissues. Plasma levels were a poor reflection of most tissue levels.

CONCLUSION

Vitamin E levels within different lipid emulsions and plasma/tissues are highly variable, and no one tissue or plasma sample serves as a good proxy for levels in other tissues. All study emulsions were well tolerated and did not significantly increase systemic lipid peroxidation.

Understanding triglyceride levels related to intravenous fat administration

Lipid is an essential macronutrient in parenteral nutrition (PN) support. intravenous (IV) lipid provides essential fatty acids and a concentrated calorie source. Preterm infants are at risk for essential fatty deficiency early in life. Lipid administration is associated with some risks, and there are guidelines for administration to minimize complications. Lipid emulsions in the United States are derived from soybean oil. Outside of the United States, lipid emulsions made from fish oil or combinations of fish, soybean, olive, and medium-chain triglycerides (MCTs) are under investigation for improved tolerance, lower plasma lipid levels, and improved fatty acid profiles, all of which are considered beneficial. Triglyceride levels are an important measurement to assess patient tolerance.

Dependence of optical scattering from Intralipid in gelatin-gel based tissue-mimicking phantoms on mixing temperature and time

Intralipid is widely used as an optical scattering agent in tissue-mimicking phantoms. Accurate control when using Intralipid is critical to match the optical diffusivity of phantoms to the prescribed value. Currently, most protocols of Intralipid-based hydrogel phantom fabrication focus on factors such as Intralipid brand and concentration. In this note, for the first time to our knowledge, we explore the dependence of the optical reduced scattering coefficient (at 532 nm optical wavelength) on the temperature and the time of mixing Intralipid with gelatin-water solution. The studied samples contained 1% Intralipid and were measured with oblique-incidence reflectometry. It was found that the reduced scattering coefficient increased when the Intralipid-gelatin-water mixture began to solidify at room temperature. For phantoms that had already solidified completely, the diffusivity was shown to be significantly influenced by the temperature and the duration of the mixing course. The dependence of the measured diffusivity on the mixing conditions was confirmed by experimental observations. Moreover, the mechanism behind the dependence behavior is discussed.

Parenteral fish oil lipid emulsions in the critically ill: a systematic review and meta-analysis

INTRODUCTION

ω-3 Polyunsaturated fatty acids contained in fish oils (FO) possess major anti-inflammatory, antioxidant, and immunologic properties that could be beneficial during critical illness. We hypothesized that parenteral FO-containing emulsions may improve clinical outcomes in the critically ill.

METHODS

We searched computerized databases from 1980-2012. We included randomized controlled trials (RCTs) conducted in critically ill adult patients that evaluated FO-containing emulsions, either in the context of parenteral nutrition (PN) or enteral nutrition (EN).

RESULTS

A total of 6 RCTs (n = 390 patients) were included; the mean methodological score of all trials was 10 (range, 6-13). When the results of these studies were aggregated, FO-containing emulsions were associated with a trend toward a reduction in mortality (risk ratio [RR], 0.71; 95% confidence interval [CI], 0.49-1.04; P = .08; heterogeneity I (2) = 0%) and a reduction in the duration of mechanical ventilation (weighted mean difference in days [WMD], -1.41; 95% CI, -3.43 to 0.61; P = .17). However, this strategy had no effect on infections (RR, 0.76; 95% CI, 0.42-1.36; P = .35) and intensive care unit length of stay (WMD, -0.46; 95% CI, -4.87 to 3.95; P = .84, heterogeneity I (2) = 75%).

CONCLUSION

FO-containing lipid emulsions may be able to decrease mortality and ventilation days in the critically ill. However, because of the paucity of clinical data, there is inadequate evidence to recommend the routine use of parenteral FO. Large, rigorously designed RCTs are required to elucidate the efficacy of parenteral FO in the critically ill.

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.

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.

Lipid emulsions - Guidelines on Parenteral Nutrition, Chapter 6

The infusion of lipid emulsions allows a high energy supply, facilitates the prevention of high glucose infusion rates and is indispensable for the supply with essential fatty acids. The administration of lipid emulsions is recommended within ≤7 days after starting PN (parenteral nutrition) to avoid deficiency of essential fatty acids. Low-fat PN with a high glucose intake increases the risk of hyperglycaemia. In parenterally fed patients with a tendency to hyperglycaemia, an increase in the lipid-glucose ratio should be considered. In critically ill patients the glucose infusion should not exceed 50% of energy intake. The use of lipid emulsions with a low phospholipid/triglyceride ratio is recommended and should be provided with the usual PN to prevent depletion of essential fatty acids, lower the risk of hyperglycaemia, and prevent hepatic steatosis. Biologically active vitamin E (α-tocopherol) should continuously be administered along with lipid emulsions to reduce lipid peroxidation. Parenteral lipids should provide about 25–40% of the parenteral non-protein energy supply. In certain situations (i.e. critically ill, respiratory insufficiency) a lipid intake of up to 50 or 60% of non-protein energy may be reasonable. The recommended daily dose for parenteral lipids in adults is 0.7–1.3 g triglycerides/kg body weight. Serum triglyceride concentrations should be monitored regularly with dosage reduction at levels >400 mg/dl (>4.6 mmol/l) and interruption of lipid infusion at levels >1000 mg/dl (>11.4 mmol/l). There is little evidence at this time that the choice of different available lipid emulsions affects clinical endpoints.