Antioxidant status of surgical patients receiving TPN with an omega-3-fatty acid-containing lipid emulsion supplemented with alpha-tocopherol

An Overview of Short-Bowel Syndrome in Pediatric Patients: Focus on Clinical Management and Prevention of Complications

Short-bowel syndrome (SBS) in pediatric age is defined as a malabsorptive state, resulting from congenital malformations, significant small intestine surgical resection or disease-associated loss of absorption. SBS is the leading cause of intestinal failure in children and the underlying cause in 50% of patients on home parental nutrition. It is a life-altering and life-threatening disease due to the inability of the residual intestinal function to maintain nutritional homeostasis of protein, fluid, electrolyte or micronutrient without parenteral or enteral supplementation. The use of parenteral nutrition (PN) has improved medical care in SBS, decreasing mortality and improving the overall prognosis. However, the long-term use of PN is associated with the incidence of many complications, including liver disease and catheter-associated malfunction and bloodstream infections (CRBSIs). This manuscript is a narrative review of the current available evidence on the management of SBS in the pediatric population, focusing on prognostic factors and outcome. The literature review showed that in recent years, the standardization of management has demonstrated to improve the quality of life in these complex patients. Moreover, the development of knowledge in clinical practice has led to a reduction in mortality and morbidity. Diagnostic and therapeutic decisions should be made by a multidisciplinary team that includes neonatologists, pediatric surgeons, gastroenterologists, pediatricians, nutritionists and nurses. A significant improvement in prognosis can occur through the careful monitoring of nutritional status, avoiding dependence on PN and favoring an early introduction of enteral nutrition, and through the prevention, diagnosis and aggressive treatment of CRSBIs and SIBO. Multicenter initiatives, such as research consortium or data registries, are mandatory in order to personalize the management of these patients, improve their quality of life and reduce the cost of care.

Role of the Gut Microbiota in Parenteral Nutrition-Associated Liver Disease: From Current Knowledge to Future Opportunities

Parenteral nutrition-associated liver disease (PNALD) refers to a spectrum of conditions that can develop cholestasis, steatosis, fibrosis, and cirrhosis in the setting of parenteral nutrition (PN) use. Patient risk factors include short bowel syndrome, bacterial overgrowth and translocation, disturbance of hepatobiliary circulation, and lack of enteral feeding. A growing body of evidence suggests an intricate linkage between the gut microbiota and the pathogenesis of PNALD. In this review, we highlight current knowledge on the taxonomic and functional changes in the gut microbiota that might serve as noninvasive biomarkers. We also discuss the function of microbial metabolites and associated signaling pathways in the pathogenesis of PNALD. By providing the perspectives of microbiota-host interactions in PNALD for basic and translational research and summarizing current limitations of microbiota-based approaches, this review paves the path for developing novel and precise microbiota-based therapies in PNALD.

Narrative Review of n-3 Polyunsaturated Fatty Acid Supplementation upon Immune Functions, Resolution Molecules and Lipid Peroxidation

Fish oil supplementation is commonplace in human nutrition and is being used in both enteral and parenteral formulations during the treatment of patients with a large variety of diseases and immune status. The biological effects of fish oil are believed to result from their content of n-3 polyunsaturated fatty acids (PUFA), particularly docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). These fatty acids are known to have numerous effects upon immune functions and are described as immunomodulatory. However, immunomodulatory is a nondescript term that encompasses immunostimulation and immunosuppression. The primary goal of this review is to better describe the immune effects of n-3 PUFA as they relate to immunostimulatory vs. immunosuppressive effects. One mechanism proposed for the immune effects of n-3 PUFA relates to the production of specialized pro-resolving mediators (SPMs). A second goal of this review is to evaluate the effects of n-3 PUFA supplementation upon production of SPMs. Although n-3 PUFA are stated to possess anti-oxidative properties, these molecules are highly oxidizable due to multiple double bonds and may increase oxidative stress. Thus, the third goal of this review is to evaluate the effects of n-3 PUFA upon lipid oxidation. We conclude, based upon current scientific evidence, that n-3 PUFA suppress inflammatory responses and most cellular immune responses such as chemotaxis, transmigration, antigen presentation, and lymphocyte functions and should be considered immunosuppressive. n-3 PUFA induced production of resolution molecules is inconsistent with many resolution molecules failing to respond to n-3 PUFA supplementation. n-3 PUFA supplementation is associated with increased lipid peroxidation in most studies. Vitamin E co-administration is unreliable for prevention of the lipid peroxidation. These effects should be considered when administering n-3 PUFA to patients that may be immunosuppressed or under high oxidative stress due to illness or other treatments.

Nutritional Neuroscience as Mainstream of Psychiatry: The Evidence- Based Treatment Guidelines for Using Omega-3 Fatty Acids as a New Treatment for Psychiatric Disorders in Children and Adolescents

Omega-3 polyunsaturated fatty acids (or omega-3 PUFAs, n-3 PUFAs) are essential nutrients throughout the life span. Recent studies have shown the importance of n-3 PUFAs supplementation during prenatal and perinatal period as a potential protective factor of neurodevelopmental disorders. N-3 PUFAs have been reported to be lower in youth with attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD) and major depressive disorder (MDD). N-3 PUFAs supplementation has shown potential effects in the improvement of clinical symptoms in youth with ADHD, ASD, and MDD, especially those with high inflammation or a low baseline n-3 index. Moreover, it has been suggested that n-3 PUFAs had positive effects on lethargy and hyperactivity symptoms in ASD. For clinical application, the following dosage and duration are recommended in youth according to available randomized controlled trials and systemic literature review: (1) ADHD: a combination of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) ≥ 750 mg/d, and a higher dose of EPA (1,200 mg/d) for those with inflammation or allergic diseases for duration of 16−24 weeks; (2) MDD: a combination of a EPA + DHA of 1,000−2,000 mg/d, with EPA:DHA ratio of 2 to 1, for 12−16 weeks; (3) ASD: a combination of EPA + DHA of 1,300−1,500 mg/d for 16−24 weeks as add-on therapy to target lethargy and hyperactivity symptoms. The current review also suggested that n-3 index and inflammation may be potential treatment response markers for youth, especially in ADHD and MDD, receiving n-3 PUFA.

The ω-3 Polyunsaturated Fatty Acids and Oxidative Stress in Long-Term Parenteral Nutrition Dependent Adult Patients: Functional Lipidomics Approach

Omega-3 polyunsaturated fatty acids (ω-3PUFAs) are introduced into parenteral nutrition (PN) as hepatoprotective but may be susceptible to the lipid peroxidation while olive oil (OO) is declared more peroxidation resistant. We aimed to estimate how the lipid composition of PN mixture affects plasma and erythrocyte lipidome and the propensity of oxidative stress. A cross-sectional comparative study was performed in a cohort of adult patients who were long-term parenterally administered ω-3 PUFAs without (FO/–, n = 9) or with (FO/OO, n = 13) olive oil and healthy age- and sex-matched controls, (n = 30). Lipoperoxidation assessed as plasma and erythrocyte malondialdehyde content was increased in both FO/– and FO/OO groups but protein oxidative stress (protein carbonyls in plasma) and low redox status (GSH/GSSG in erythrocytes) was detected only in the FO/– subcohort. The lipidome of all subjects receiving ω-3 PUFAs was enriched with lipid species containing ω-3 PUFAs (FO/–˃FO/OO). Common characteristic of all PN-dependent patients was high content of fatty acyl-esters of hydroxy-fatty acids (FAHFAs) in plasma while acylcarnitines and ceramides were enriched in erythrocytes. Plasma and erythrocyte concentrations of plasmanyls and plasmalogens (endogenous antioxidants) were decreased in both patient groups with a significantly more pronounced effect in FO/–. We confirmed the protective effect of OO in PN mixtures containing ω-3 PUFAs.

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.

Nutrition in Necrotizing Enterocolitis and Following Intestinal Resection

This review aims to discuss the role of nutrition and feeding practices in necrotizing enterocolitis (NEC), NEC prevention, and its complications, including surgical treatment. A thorough PubMed search was performed with a focus on meta-analyses and randomized controlled trials when available. There are several variables in nutrition and the feeding of preterm infants with the intention of preventing necrotizing enterocolitis (NEC). Starting feeds later rather than earlier, advancing feeds slowly and continuous feeds have not been shown to prevent NEC and breast milk remains the only effective prevention strategy. The lack of medical treatment options for NEC often leads to disease progression requiring surgical resection. Following resection, intestinal adaptation occurs, during which villi lengthen and crypts deepen to increase the functional capacity of remaining bowel. The effect of macronutrients on intestinal adaptation has been extensively studied in animal models. Clinically, the length and portion of intestine that is resected may lead to patients requiring parenteral nutrition, which is also reviewed here. There remain significant gaps in knowledge surrounding many of the nutritional aspects of NEC and more research is needed to determine optimal feeding approaches to prevent NEC, particularly in infants younger than 28 weeks and <1000 grams. Additional research is also needed to identify biomarkers reflecting intestinal recovery following NEC diagnosis individualize when feedings should be safely resumed for each patient.

ω-3 fish oil fat emulsion preconditioning mitigates myocardial oxidative damage in rats through aldehydes stress

ω-3 fish oil fat emulsions contain a considerable quantity of unsaturated carbon-carbon double bonds, which undergo lipid peroxidation to yield low-dose aldehydes. These aldehydes may stimulate the production of antioxidant enzymes, thereby mitigating myocardial oxidative damage. This study aims to (1) verify the cardioprotective effect of ω-3 fish oil fat emulsion in vivo and in vitro, and (2) determine whether aldehyde stress is a protective mechanism. For modeling purposes, we pretreated rats with 2 ml/kg of a 10% ω-3 fish oil fat emulsion for 5 days in order to generate a sufficient aldehyde stress response to trigger the production of antioxidant enzymes, and we obtained similar response with H9C2 cells that were pretreated with a 0.5% ω-3 fish oil fat emulsion for 24 h. ω-3 fish oil fat emulsion pretreatment in vivo reduced the myocardial infarct size, decreased the incidence of arrhythmias, and promoted the recovery of cardiac function after myocardial ischemia/reperfusion injury. Once the expression of nuclear factor E2-related factor 2 (Nrf2) was silenced in H9C2 cells, aldehydes no longer produced enough antioxidant enzymes to reverse the oxidative damage caused by tert-butyl hydroperoxide (TBHP). Our results demonstrated that ω-3 fish oil fat emulsion enhanced the inhibition of oxidation and production of free radicals, and alleviated myocardial oxidative injury via activation of the Nrf2 signaling pathway.

Short Bowel Syndrome as the Leading Cause of Intestinal Failure in Early Life: Some Insights into the Management

Intestinal failure (IF) is the critical reduction of the gut mass or its function below the minimum needed to absorb nutrients and fluids required for adequate growth in children. Severe IF requires parenteral nutrition (PN). Pediatric IF is most commonly due to congenital or neonatal intestinal diseases or malformations divided into 3 groups: 1) reduced intestinal length and consequently reduced absorptive surface, such as in short bowel syndrome (SBS) or extensive aganglionosis; 2) abnormal development of the intestinal mucosa such as congenital diseases of enterocyte development; 3) extensive motility dysfunction such as chronic intestinal pseudo-obstruction syndromes. The leading cause of IF in childhood is the SBS. In clinical practice the degree of IF may be indirectly measured by the level of PN required for normal or catch up growth. Other indicators such as serum citrulline have not proven to be highly reliable prognostic factors in children. The last decades have allowed the development of highly sophisticated nutrient solutions consisting of optimal combinations of macronutrients and micronutrients as well as guidelines, promoting PN as a safe and efficient feeding technique. However, IF that requires long-term PN may be associated with various complications including infections, growth failure, metabolic disorders, and bone disease. IF Associated Liver Disease may be a limiting factor. However, changes in the global management of IF pediatric patients, especially since the setup of intestinal rehabilitation centres did change the prognosis thus limiting "nutritional failure" which is considered as a major indication for intestinal transplantation (ITx) or combined liver-ITx.

ω-3 Fatty-Acid Enriched Parenteral Nutrition in Hospitalized Patients: Systematic Review With Meta-Analysis and Trial Sequential Analysis

This systematic review and meta-analysis investigated ω-3 fatty-acid enriched parenteral nutrition (PN) vs standard (non-ω-3 fatty-acid enriched) PN in adult hospitalized patients (PROSPERO 2018 CRD42018110179). We included 49 randomized controlled trials (RCTs) with intervention and control groups given ω-3 fatty acids and standard lipid emulsions, respectively, as part of PN covering ≥70% energy provision. The relative risk (RR) of infection (primary outcome; 24 RCTs) was 40% lower with ω-3 fatty-acid enriched PN than standard PN (RR 0.60, 95% confidence interval [CI] 0.49-0.72; P < 0.00001). Patients given ω-3 fatty-acid enriched PN had reduced mean length of intensive care unit (ICU) stay (10 RCTs; 1.95 days, 95% CI 0.42-3.49; P = 0.01) and reduced length of hospital stay (26 RCTs; 2.14 days, 95% CI 1.36-2.93; P < 0.00001). Risk of sepsis (9 RCTs) was reduced by 56% in those given ω-3 fatty-acid enriched PN (RR 0.44, 95% CI 0.28-0.70; P = 0.0004). Mortality rate (co-primary outcome; 20 RCTs) showed a nonsignificant 16% reduction (RR 0.84, 95% CI 0.65-1.07; P = 0.15) for the ω-3 fatty-acid enriched group. In summary, ω-3 fatty-acid enriched PN is beneficial, reducing risk of infection and sepsis by 40% and 56%, respectively, and length of both ICU and hospital stay by about 2 days. Provision of ω-3-enriched lipid emulsions should be preferred over standard lipid emulsions in patients with an indication for PN.

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.

Intravenous fish oil in critically ill and surgical patients - Historical remarks and critical appraisal

The purpose of this review is to explain the historical and clinical background for intravenous fish oil administration, to evaluate its results by using a product specific metaanalysis, and to stimulate further research in the immune-modulatory potential of fish oil. Concerning the immune-modulatory effects of fatty acids, a study revealed that ω-3 as well as ω-6 fatty acids would prolong transplant survival, and only a mixture with an ω-6:ω-3 ratio of 2.1:1 would give immune-neutral results. In 1998, the label of a newly registered fish oil emulsion also acknowledged this immune-neutral ratio in conjunction with ω-6 lipids. Also, two fish oil-supplemented fat emulsions, registered in 2004, used a similar ω-6:ω-3 ratio. Such an immune-neutral ω-6:ω-3 ratio denoted progress for most patients compared to pure ω-6 lipid emulsions. However, this immune-neutrality might on the other hand be responsible for the limited positive clinical results gained so far in critically ill and surgical patients where in most cases significance could only be shown for the pooled effect of numerous trials. Our product specific metaanalysis also did not reveal any differences, neither in infections rates nor in ICU or hospital length of stay. To evaluate the immune-modulatory effect of fish oil administered alone, new dose finding studies, reporting relevant clinical outcome parameters, are required. Precise mechanistic or physiological biomarkers for the indication of such a therapy should also be developed and validated.

New Parenteral Lipid Emulsions for Clinical Use

Routine use of parenteral lipid emulsions (LE) in clinical practice began in 1961, with the development of soybean oil (SO) - based LE. Although clinically safe, experimental reports indicated that SO-based LE could exert a negative influence on immunological functions. Those findings were related to its absolute and relative excess of omega-6 polyunsaturated fatty acids (PUFA) and the low amount of omega-3 PUFA and also to its high PUFA content with an increased peroxidation risk. This motivated the development of new LE basically designed along the reduction of omega-6 PUFA and the omega-3 PUFA addition in order to obtain balanced levels of the omega-6/omega-3 ratio. The new LE for clinical use (available in Europe and South America) are differentiated by their content in polyunsaturated (omega-6 and omega-3), monounsaturated, and saturated fatty acids (FA), as well as FA source of their origin, including soy, coconut, olive, and fish oil. This article presents the new LE nutrition and energy functions but also its biochemical, metabolic, and immunomodulating aspects, according to their FA content. LE at 20% when infused from 1.0 to 2.0 g/kg body weight/day rates, either alone or in association with amino acids and glucose, are safe and well tolerated in routine clinical practice. LE combining SO with medium-chain triglycerides and/or olive oil have less omega-6 PUFA and are better metabolized, with less inflammatory and immunosuppressive effects than in relation to pure SO-based LE. The omega-3 PUFA used alone or as component of a new and complex LE (soy, MCT, olive and fish oil) has demonstrated anti-inflammatory and immunomodulatory effects.

ESPGHAN Committee on Nutrition Position Paper. Intravenous Lipid Emulsions and Risk of Hepatotoxicity in Infants and Children: a Systematic Review and Meta-analysis

The aim of the present article was to perform a systematic review with meta-analysis of available scientific evidence regarding the role of different intravenous lipid emulsions (ILE) in the pathogenesis of cholestasis and parenteral nutrition-associated liver disease. A systematic review of the literature (up to March 2015) identified 23 randomized controlled trials (RCTs). Of these, 17 were performed in preterm infants or critically ill neonates with a short duration of intervention, 2 in older children with short-term use (following surgery or bone marrow transplantation), 1 in neonates with long-term use, and 3 in infants and children receiving long-term parenteral nutrition (PN). Meta-analysis showed no differences in the rate of cholestasis or bilirubin levels associated with short-term use of different ILEs. Because of high heterogeneity of the long-term studies no meta-analysis could be performed. Available studies found that the use of multicomponent fish oil (FO)-containing ILE compared with pure soya bean oil (SO), ILE-reduced liver enzymes, and bilirubin levels in noncholestatic children on long-term PN and one other RCT found that FO-based ILE-reversed cholestasis in a proportion of patients. The ESPGHAN Committee on Nutrition concludes that there is no evidence of a difference in rates of cholestasis or bilirubin levels between different ILE for short-term use in neonates. The use of multicomponent FO-containing ILE may contribute to a decrease in total bilirubin levels in children with IF on prolonged PN. Well-designed RCTs are, however, lacking and long-term effects have not been determined.

Lipid emulsions for parenteral nutrition in critical illness

Critical illness is a life-threatening multisystem process that can result in significant morbidity and mortality. In most patients, critical illness is preceded by a physiological deterioration, characterized by a catabolic state and intense metabolic changes, resulting in malnutrition and impaired immune functions. In this context, parenteral lipid emulsions may modulate inflammatory and immune reactions, depending on their fatty acid composition. These effects appear to be based on complex modifications in the composition and structure of cell membranes, through eicosanoid and cytokine synthesis and by modulation of gene expression. The pathophysiological mechanisms underlying these fatty acid-induced immune function alterations in critical ill patients are however complex and partially understood. Indeed, despite a very abundant literature, experimental and clinical data remain contradictory. The optimization of lipid emulsion composition thus represents a major challenge for clinical medicine, to adequately modulate the inflammatory pathways. In the present review, we first address the metabolic response to aggression, the effects of parenteral lipid emulsions on inflammation and immunity, and finally the controversial place of these lipid emulsions during critical illness. The analysis furthermore highlights the pathophysiological mechanisms underlying the differential effects of lipid emulsions and their potential for improving the handling of critically ill patients.

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.

Antioxidants in Cardiovascular Therapy: Panacea or False Hope?

Oxidative stress is a key feature of the atherothrombotic process involved in the etiology of heart attacks, ischemic strokes, and peripheral arterial disease. It stands to reason that antioxidants represent a credible therapeutic option to prevent disease progression and thereby improve outcome, but despite positive findings from in vitro studies, clinical trials have failed to consistently show benefit. The aim of this review is to re-appraise the concept of antioxidants in the prevention and management of cardiovascular disease. In particular, the review will explore the reasons behind failed antioxidant strategies with vitamin supplements and will evaluate how flavonoids might improve cardiovascular function despite bioavailability that is not sufficiently high to directly influence antioxidant capacity. As well as reaching conclusions relating to those antioxidant strategies that might hold merit, the major myths, limitations, and pitfalls associated with this research field are explored.

Intravenous fish oil lipid emulsions in critically ill patients: an updated systematic review and meta-analysis

INTRODUCTION

Intravenous fish oil (FO) lipid emulsions (LEs) are rich in ω-3 polyunsaturated fatty acids, which exhibit anti-inflammatory and immunomodulatory effects. We previously demonstrated that FO-containing LEs may be able to decrease mortality and ventilation days in patients who are critically ill. Since 2014, several additional randomized controlled trials (RCTs) of FO-containing LEs have been published. Therefore, the purpose of this systematic review was to update our previous systematic review with the aim of elucidating the efficacy of FO-containing LEs on clinical outcomes of patients who are critically ill.

METHODS

We searched electronic databases from 1980 to 2014. We included four new RCTs conducted in critically ill adult patients in which researchers evaluated FO-containing LEs in parenterally or enterally fed patients.

RESULTS

A total of 10 RCTs (n = 733) met inclusion criteria. The mean methodological score was 8 (range, 3 to 12). No effect on overall mortality was found. When we aggregated the results of five RCTs in which infections were reported, we found that FO-containing LEs significantly reduced infections (risk ratio (RR) = 0.64; 95% confidence interval (CI), 0.44 to 0.92; P = 0.02; heterogeneity I (2) = 0%). Subgroup analysis demonstrated that predominantly enteral nutrition-based trials showed a tendency toward a reduction in mortality (RR = 0.69; 95% CI, 0.40 to 1.18; P =0.18; heterogeneity I (2) =35%). High-quality trials showed a significant reduction in hospital length of stay (LOS) (weighted mean difference = -7.42; 95% CI, -11.89 to -2.94; P = 0.001), whereas low-quality trials had no effect (P = 0.45). The results of the test for subgroup differences in hospital LOS was significant (P = 0.001).

CONCLUSION

FO-containing LEs may be associated with a reduction in infections and also could be associated with a reduction in duration of ventilation and hospital LOS. Further large-scale RCTs are warranted and should be aimed at consolidating potential positive treatment effects.

Intestinal failure-associated liver disease: a position paper of the ESPGHAN Working Group of Intestinal Failure and Intestinal Transplantation

Intestinal failure-associated liver disease is the most prevalent complication affecting children with intestinal failure receiving long-term parenteral nutrition. This paper reviews the definition, diagnostic criteria, pathogenesis, and risk factors. The authors discuss the role of enteral nutrition, parenteral nutrition, and its components, especially lipid emulsions. The authors also discuss the surgical treatment, including intestinal transplantation, its indications, technique, and results, and emphasise the importance of specialised intestinal failure centres.

Supplementation of parenteral nutrition with fish oil attenuates acute lung injury in a rat model

Fish oil rich in n-3 polyunsaturated fatty acids has diverse immunomodulatory properties and attenuates acute lung injury when administered in enternal nutrition. However, enteral nutrition is not always feasible. Therefore, we investigated the ability of parenteral nutrition supplemented with fish oil to ameliorate acute lung injury. Rats were infused with parenteral nutrition solutions (without lipids, with soybean oil, or with soybean oil and fish oil) for three days. Lipopolysaccharide (15 mg/kg) was then administered intratracheally to induce acute lung injury, characterized by impaired lung function, polymorphonuclear leukocyte recruitment, parenchymal tissue damage, and upregulation of mRNAs for inflammatory mediators. Administration of parenteral nutrition supplemented with fish oil prior to lung insult improved gas exchange and inhibited neutrophil recruitment and upregulation of mRNAs for inflammatory mediators. Parenteral nutrition supplemented with fish oil also prolonged survival. To investigate the underlying mechanisms, leukotriene B₄ and leukotriene B₅ secretion was measured in neutrophils from the peritoneal cavity. The neutrophils from rats treated with fish oil-rich parenteral nutrition released significantly more leukotriene B₅, an anti-inflammatory eicosanoid, than neutrophils isolated from rats given standard parenteral nutrition. Parenteral nutrition with fish oil significantly reduced lipopolysaccharide-induced lung injury in rats in part by promoting the synthesis of anti-inflammatory eicosanoids.

Randomized clinical trial of new intravenous lipid (SMOFlipid 20%) versus medium-chain triglycerides/long-chain triglycerides in adult patients undergoing gastrointestinal surgery

BACKGROUND

SMOFlipid 20% is intravenous lipid emulsion (ILE) containing long-chain triglycerides (LCT), medium-chain triglycerides (MCT), olive oil, and fish oil as a mixed emulsion containing α-tocopherol. The aim was to assess the efficacy of this new ILE in gastrointestinal surgery compared with MCT/LCT.

METHODS

In this prospective study, 40 patients were randomized to SMOFlipid 20% or MCT/LCT (Lipovenoes 20%) group. Clinical and biochemistry data were collected. Inflammatory markers (CRP, IL-6, IL-10, TNF-α, TGF-β1) and oxidative stress (ROS and superoxide) were measured.

RESULTS

Thirty-five patients (17 males and 18 females) with a mean age of 57 years completed the study. The patients' demographic characteristics (age, gender, height, body weight, and BMI) were similar without significant differences between groups. The increment of triglyceride on day 6 from baseline was significantly lower in SMOFlipid group than in Lipovenoes MCT/LCT group. Inflammatory markers, as well as superoxide radical and total oxygen radical were not different between groups.

CONCLUSIONS

Despite the comparable effect on inflammatory response, because of its well-balanced fatty acid pattern, relatively low n-6:n-3 ratio, and high vitamin E content, SMOFlipid had a better triglyceride-lowering effect as compared with MCT/LCT in adult patients undergoing gastrointestinal surgery.

Alternative lipid emulsions in the critically ill: a systematic review of the evidence

PURPOSE

Parenteral lipid emulsions (LEs) are commonly rich in long-chain triglycerides derived from soybean oil (SO). SO-containing emulsions may promote systemic inflammation and therefore may adversely affect clinical outcomes. We hypothesized that alternative oil-based LEs (SO-sparing strategies) may improve clinical outcomes in critically ill adult patients compared to products containing SO emulsion only. The purpose of this systematic review was to evaluate the effect of parenteral SO-sparing strategies on clinical outcomes in intensive care unit (ICU) patients.

METHODS

We searched computerized databases from 1980 to 2013. We included randomized controlled trials (RCTs) conducted in critically ill adult patients that evaluated SO-sparing strategies versus SO-based LEs in the context of parenteral nutrition.

RESULTS

A total of 12 RCTs met the inclusion criteria. When the results of these RCTs were statistically aggregated, SO-sparing strategies were associated with clinically important reductions in mortality (risk ratio, RR 0.83; 95 % confidence intervals, CI 0.62, 1.11; P = 0.20), in duration of ventilation (weighted mean difference, WMD -2.57; 95 % CI -5.51, 0.37; P = 0.09), and in ICU length of stay (LOS) (WMD -2.31; 95 % CI -5.28, 0.66; P = 0.13) but none of these differences were statistically significant. SO-sparing strategies had no effect on infectious complications (RR 1.13; 95 % CI 0.87, 1.46; P = 0.35).

CONCLUSION

Alternative oil-based LEs may be associated with clinically important reductions in mortality, duration of ventilation, and ICU LOS but lack of statistical precision precludes any clinical recommendations at this time. Further research is warranted to confirm these potential positive treatment effects.

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 effects of n-3 polyunsaturated fatty acid-rich total parenteral nutrition on neutrophil apoptosis in a rat endotoxemia

Although recruited neutrophils function as first-line defense to remove bacteria, delayed apoptosis is implicated in persistent inflammation leading to organ injury. Leukotrien B4, n-6 polyunsaturated fatty acids (PUFAs) product, is one of the mediators that delay neutrophil apoptosis. The mechanism of the beneficial effects of supplementation of fish oil-based long-chain n-3 PUFAs in parenteral nutrition for critically ill patients has not been fully understood. One possible mechanism is the less inflammatory n-3 PUFAs products can compete with proinflammatory n-6 PUFAs products for access to the enzymes. The aim of this study was to determine whether n-3 PUFA rich parenteral nutrition may alter the composition of fatty acids in the neutrophil membrane and restore delay of neutrophil apoptosis during endotoxin-induced systemic inflammation in rats. The animals in group 1 were treated with 20% Hicaliq NC-N in Neoparen-2 for three days. The animals in group 2 (referred to as n-6 PUFA-rich parenteral nutrition) were given parenteral nutrition solutions containing 20% soybean oil in Neoparen-2 (n-6/n-3 = 10). The animals in group 3 (referred to as n-3 PUFA-rich parenteral nutrition) were administered parenteral nutrition consisting of 10% soybean oil and 10% fish oil emulsion (n-6/n-3 = 1.3). The n-3/n-6 ratio of the neutrophil membrane was significantly increased in group 3 and was associated with restored lipopolysaccharide-delayed-apoptosis of neutrophils in bone marrow cells and increased production of leukotriene B5 from peritoneal neutrophils stimulated by lipopolysaccharide. Our preliminary results showed that n-3 PUFA-rich parenteral nutrition regulated neutrophil apoptosis and prevented synthesis of pro-inflammatory eicosanoids, explaining the protective effects seen in the clinical setting.

n-3 fatty acid-enriched parenteral nutrition regimens in elective surgical and ICU patients: a meta-analysis

INTRODUCTION

Previous studies and a meta-analysis in surgical patients indicate that supplementing parenteral nutrition regimens with n-3 polyunsaturated fatty acids (PUFAs), in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), is associated with improved laboratory and clinical outcomes in the setting of hyper-inflammatory conditions. Refined or synthetic fish oils are commonly used as a source of EPA and DHA. The objective of the present meta-analysis was to evaluate n-3 PUFA-enriched parenteral nutrition regimens in elective surgical and intensive care unit (ICU) patients.

METHODS

Medline was searched for randomized controlled trials comparing n-3 PUFA-enriched lipid emulsions with standard non-enriched lipid emulsions (i.e. soybean oil, MCT/LCT or olive/soybean oil emulsions) in surgical and ICU patients receiving parenteral nutrition. Extracted data were pooled by means of both random and fixed effects models, and subgroup analyses were carried forward to compare findings in ICU versus non-ICU patients.

RESULTS

A total of 23 studies (n = 1502 patients: n = 762 admitted to the ICU) were included. No statistically significant difference in mortality rate was found between patients receiving n-3 PUFA-enriched lipid emulsions and those receiving standard lipid emulsions (RR = 0.89; 0.59, 1.33), possibly reflecting a relatively low underlying mortality risk. However, n-3 PUFA-enriched emulsions are associated with a statistically and clinically significant reduction in the infection rate (RR = 0.61; 0.45, 0.84) and the lengths of stay, both in the ICU (-1.92; -3.27, -0.58) and in hospital overall (-3.29; -5.13, -1.45). Other beneficial effects included reduced markers of inflammation, improved lung gas exchange, liver function, antioxidant status and fatty acid composition of plasma phospholipids, and a trend towards less impairment of kidney function.

CONCLUSIONS

These results confirm and extend previous findings, indicating that n-3 PUFAs-enriched parenteral nutrition regimens are safe and effective in reducing the infection rate and hospital/ICU stay in surgical and ICU patients.

Stressing the heart of the matter: re-thinking the mechanisms underlying therapeutic effects of n-3 polyunsaturated fatty acids

Despite their clear therapeutic effects in coronary heart disease, use of n-3 polyunsaturated fatty acids (PUFAs) to treat other types of cardiovascular disease remains controversial, and serious obstacles exist in implementing them as a reliable and consistent drug therapy. The foremost of these is that a molecular mechanism and relevant dosages have not been firmly established in other forms of cardiovascular disease. In this brief review, we highlight the current state of knowledge regarding the mechanisms behind n-3 PUFA action in the cardiovascular system. We also propose the novel hypothesis that lipid peroxidation products derived from n-3 PUFAs may be driving much of their beneficial cardiovascular effects, particularly in the myocardium. We conclude by discussing evidence to support this hypothesis, and its possible clinical ramifications.

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.

n-3 PUFAs in cancer, surgery, and critical care: a systematic review on clinical effects, incorporation, and washout of oral or enteral compared with parenteral supplementation

BACKGROUND

n-3 (omega-3) Fatty acids (FAs) may have beneficial effects in patients with cancer or in patients who undergo surgery or critical care.

OBJECTIVE

Our aim was to systematically review the effects of oral or enteral and parenteral n-3 FA supplementation on clinical outcomes and to describe the incorporation of n-3 FAs into phospholipids of plasma, blood cells, and mucosal tissue and the subsequent washout in these patients.

DESIGN

We investigated the supplementation of n-3 FAs in these patients by using a systematic literature review.

RESULTS

In cancer, the oral or enteral supplementation of n-3 FAs contributed to the maintenance of body weight and quality of life but not to survival. We did not find any studies on parenteral supplementation of n-3 FAs in cancer. In surgical oncology, we did not find any studies on enteral supplementation of n-3 FAs. However, postoperative parenteral supplementation in surgical oncology may reduce the length of a hospital stay. For general surgery, we did not find any studies on enteral supplementation of n-3 FAs, and evidence on parenteral supplementation was insufficient. In critical care, enteral supplementation of n-3 FAs had beneficial effects on clinical outcomes; evidence on parenteral supplementation in critical care was inconsistent. The incorporation of n-3 FAs in plasma and blood cells was slower with enteral supplementation (4-7 d) than with parenteral supplementation (1-3 d). The washout was 5-7 d.

CONCLUSIONS

This review shows the beneficial effects of n-3 FA supplementation in cancer, surgical oncology, and critical care patients. Supplementation in these specific patient populations could be considered with the route of administration taken into account.

Safety and efficacy of fish oil-enriched parenteral nutrition regimen on postoperative patients undergoing major abdominal surgery: a meta-analysis of randomized controlled trials

BACKGROUND

To evaluate the safety and efficacy of a fish oil-enriched parenteral nutrition regimen in patients undergoing major abdominal surgery, a meta-analysis of randomized controlled trials was conducted.

METHODS

An electronic search of PubMed, MEDLINE, EMBASE, Academic Search Premier, and China National Knowledge Infrastructure databases was performed in March 2009. RevMan 5.0 was used for statistical analysis.

RESULTS

The combined analysis showed that a fish oil-enriched parenteral nutrition regimen had a positive treatment effect on length of hospital stay (weighed mean difference = -2.98, P < .001), length of intensive care unit stay, postoperative infection rate (odds ratio = 0.56, P = .04), and serum levels of aspartate aminotransferase, alanine aminotransferase, and alpha-tocopherol on postoperative day 6 in these patients. The regimen increased the plasma levels of eicosapentaenoic acid (standardized mean difference = 3.11, P < .001) and docosahexaenoic acid and upregulated the leukotriene B(5) production in leukocytes on postoperative day 6. No significant differences were found between the 2 groups in postoperative mortality; incidence of postoperative cardiac complications; serum levels of bilirubin, triglyceride, or arachidonic acid; or the liberation of leukotriene B(4). No serious adverse events related to fish oil treatment were reported.

CONCLUSIONS

Based on the meta-analysis, fish oil-supplemented parenteral nutrition was safe, improved clinical outcomes, and altered the fatty acid pattern as well as leukotriene synthesis. More laboratory parameters should be considered in future meta-analyses.

Fish oil containing intravenous lipid emulsions in parenteral nutrition-associated cholestatic liver disease

PURPOSE OF REVIEW

Lipid emulsions containing fish oils have been proposed to improve parenteral nutrition associated cholestasis (PNAC), a very serious complication of prolonged parenteral nutrition occurring particularly in infants and children with intestinal failure. Here, we summarize current data.

RECENT FINDINGS

The cause of PNAC is multifactorial. Prevention is possible by appropriate management, surgical procedures, infection prevention, and optimal parenteral nutrition management. Plausible hypotheses and experimental data support potential benefits of fish oils for treatment and prevention of PNAC. Improvement of PNAC over weeks and months has been reported in observational case studies in part of the children who received parenteral lipids with fish oil, but similar improvements also occurred by withholding or reducing standard lipid emulsions. No controlled trials are available that would allow final conclusions on efficacy and safety of fish oil-based emulsions in PNAC. Concerns exist regarding possible untoward effects and an inadequate supply of n-6 fatty acids with parenteral fish oil only. First data from controlled trials with mixed lipid emulsions containing partly fish oil suggest safety in infants and children and some possible benefits for liver function.

SUMMARY

The observed improvement of PNAC on parenteral lipids with fish oil deserves further exploration. No controlled trials are available, nutritional adequacy and safety of 100% fish oil emulsions are not adequately documented, and currently their use cannot be considered standard care. First data on mixed lipid emulsions with some fish oil are encouraging, and their effects in PNAC should also be explored.

Lipid emulsions in parenteral nutrition of intensive care patients: current thinking and future directions

Background

Energy deficit is a common and serious problem in intensive care units and is associated with increased rates of complications, length of stay, and mortality. Parenteral nutrition (PN), either alone or in combination with enteral nutrition, can improve nutrient delivery to critically ill patients. Lipids provide a key source of calories within PN formulations, preventing or correcting energy deficits and improving outcomes.

Discussion

In this article, we review the role of parenteral lipid emulsions (LEs) in the management of critically ill patients and highlight important biologic activities associated with lipids. Soybean-oil-based LEs with high contents of polyunsaturated fatty acids (PUFA) were the first widely used formulations in the intensive care setting. However, they may be associated with increased rates of infection and lipid peroxidation, which can exacerbate oxidative stress. More recently developed parenteral LEs employ partial substitution of soybean oil with oils providing medium-chain triglycerides, ω-9 monounsaturated fatty acids or ω-3 PUFA. Many of these LEs have demonstrated reduced effects on oxidative stress, immune responses, and inflammation. However, the effects of these LEs on clinical outcomes have not been extensively evaluated.

Conclusions

Ongoing research using adequately designed and well-controlled studies that characterize the biologic properties of LEs should assist clinicians in selecting LEs within the critical care setting. Prescription of PN containing LEs should be based on available clinical data, while considering the individual patient’s physiologic profile and therapeutic requirements.

Omega-3 lipids for intestinal failure associated liver disease

Intestinal failure associated liver disease (IFALD) is one of the most common and devastating complications in infants with intestinal failure. Although multifactorial, its pathophysiology is clearly related to the administration of parenteral nutrition (PN), with a recent focus on the role of PN lipid emulsions. This paper will review the evidence for the use of omega-3 fatty acid PN lipid emulsions, which are proposed to have efficacy in the treatment of IFALD. Mechanisms explaining their effects will be considered as will future research directions.

No evidence for oxidative stress in patients on home parenteral nutrition

BACKGROUND & AIMS

Patients on total parenteral nutrition depend on the composition of the nutritional formulation for maintenance of their oxidant-antioxidant balance. The present observational study was conducted to evaluate a substantial part of our patient population for evidence of oxidative stress.

METHODS

Venous blood samples were obtained from 41 patients on home parenteral nutrition (HPN) and 41 healthy controls. Glutathione in plasma and whole blood, glutathione peroxidase and superoxide dismutase in erythrocytes and total plasma antioxidant capacity were measured to assess the antioxidant status. Oxidant status was evaluated by measuring the production of reactive oxygen species by leukocytes. Oxidative damage was assessed by measuring lipid peroxidation and protein oxidation products.

RESULTS

Patients on HPN showed some signs of increased oxidative stress, however, there were no signs for oxidative damage, compared with healthy controls. In addition, activity of any underlying disease was not associated with increased oxidative stress.

CONCLUSIONS

The current treatment regime for patients on HPN at our center apparently prevents the development of significant oxidative damage, despite signs of some oxidative stress. Based on these data, adaptations in the composition of parenteral nutritional formulations do not seem mandatory.

Improved fatty acid and leukotriene pattern with a novel lipid emulsion in surgical patients

OBJECTIVE

We assessed the effects of a novel lipid emulsion with reduced content of n-6 fatty acids (FA), increased share of MUFA and n-3 FA and supplemental vitamin E on fatty acid and leukotriene pattern in surgical patients.

METHODS

In a double-blind, randomized study 33 patients received isonitrogenous, isocaloric TPN over 5 postoperative days following major abdominal surgery. 19 patients received the new SMOFlipid 20% and 14 patients a standard soybean oil emulsion (Lipovenoes 20%, both Fresenius Kabi), each 1.5 g fat/kg body weight (BW)/d. Routine lipid biochemistry, plasma tocopherol, fatty acid pattern in plasma phospholipids, as well as leukotriene (LT) release in leukocytes were assessed. Additionally, fatty acid pattern in leukocyte and platelet phospholipids were analysed, but results are not presented.

RESULTS

On day 6, plasma alpha-tocopherol (34.2 +/- 10.3 vs. 17.6 +/- 2.9 micromol/L) and, in plasma PL, total n-3 FA were higher (11.1 +/- 1.9 vs. 4.9 +/- 0.9 mol%; p < 0.05) and total n-6 FA lower (23.8 +/- 2.2 vs. 31.8 +/- 1.7 mol%; P < 0.05); the ratio n-3/n-6 FA being elevated (0.5 +/- 0.1 vs. 0.2 +/- 0.0 p < 0.05) with SMOFlipid compared to the soybean oil emulsion. The shares of EPA (3.3+/-1.0 vs. 0.4+/-0.2 mol%; p<0.05) and DHA (6.9 +/- 1.8 vs. 3.7 +/- 0.8 mol%; p < 0.05) were highly increased but that of arachidonic acid (AA) was unchanged with SMOFlipid while the ratio EPA/AA was increased (0.7 +/- 0.2 vs. 0.1 +/- 0.0 p < 0.05). LTB(5) release was enhanced on day 6 (8.1 +/- 5.3 vs. 1.8 +/- 3.8 pmol/10(7) PMN, p < 0.05) and liberation of LTB(4) was lowered, yet not significantly with SMOFlipid (124.0 +/- 51.2 vs. 152.1 +/- 68.8 pmol/10(7) PMN). Length of hospital stay was significantly shorter with SMOFlipid (13.4 +/- 2.0 vs. 20.4 +/- 10.0 days, p < 0.05).

CONCLUSION

Treatment with the new emulsion SMOFlipid is well tolerated and modulates FA and leukotriene pattern suggesting favourable anti-inflammatory effects and further clinical benefits.

Pilot study on the effect of parenteral vitamin E on ischemia and reperfusion induced liver injury: a double blind, randomized, placebo-controlled trial

BACKGROUND AND AIMS

Liver surgery usually involves ischemia and reperfusion (I/R) which results in oxidative stress and cell damage. The administration of antioxidants should diminish or prevent this damage. The purpose of this study was to investigate the effect of the antioxidant vitamin E on I/R injury.

METHODS

We carried out a placebo-controlled double-blind study on 68 patients undergoing elective, tumor-related, partial liver resection. 47 patients were qualified for the per protocol population based evaluation. The patients were randomly assigned to two groups. The day before surgery one group received three infusions containing vitamin E (600 IU=540 mg vitamin E emulsion). The other group received three infusions of placebo.

RESULTS

Length of stay in the intensive care unit (ICU) was significantly shorter in the verum group than in the placebo group (P<0.05). There were signs of improvement for AUC AST (P<0.05), ALT and GLDH in the verum group after surgery. Serum vitamin E concentration increased after administration of vitamin E infusion and declined in both treatment groups after surgery (P<0.01). In the verum group vitamin E deficiency was prevented while vitamin E concentration remained low in the placebo group (P<0.01).

CONCLUSIONS

The findings from this study indicate that preoperative administration of vitamin E is safe and that this treatment may have beneficial effects by reducing the impact of I/R injury in liver surgery.

Effects of intravenous supplementation with alpha-tocopherol in patients receiving total parenteral nutrition containing medium- and long-chain triglycerides

OBJECTIVE

To compare the effects of a lipid emulsion containing medium-chain triglycerides (MCT) and supplemented with alpha-tocopherol to a conventional long-chain triglyceride (LCT) emulsion.

DESIGN

Randomised double blind study.

SETTING

Department of Internal Medicine, Antwerp University Hospital.

SUBJECTS AND INTERVENTIONS

Twenty-four patients with an indication for total parenteral nutrition for a minimum of 10 days were randomly assigned to two groups: group E received as lipid source MCT/LCT (50/50) suplemented with 100 mg DL-alpha-tocopherol/day and group C received LCT. Blood samples were analysed at inclusion, after 4-6 and after 9-11 days.

RESULTS

In group E, serum alpha-tocopherol doubled from 11.4+/-6.9 at inclusion to 20.9+/-7.9 and to 23.8+/-8.8 microg/ml after 4 and 9 days, respectively, but did not change in group C (P=0.008). Production of thiobarbituric acid-reacting substances (TBARS) after 120 min incubation with copper decreased from 66+/-34 at inclusion to 29+/-25 nmol MDA/mg LDL and VLDL-cholesterol after 4 and to 42+/-17 after 9 days (P=0.022 when compared to group C, which underwent no significant changes). Velocity of production of fluorescent products decreased in group E but not in group C (P=0.026).

CONCLUSIONS

Supplementation of TPN containing MCT/LCT with 100 mg DL-alpha-tocopherol/day leads to a doubling in serum alpha-tocopherol and to a decrease in the susceptibility of LDL and VLDL to peroxidation in vitro.

SPONSORSHIP

This study was partly financed by B Braun Medical NVSA, Diegem, Belgium.