[Research progress on the application of non-nutritional effects of fat emulsion in the treatment of poisoning].

Fat emulsion is a drug commonly used clinically for parenteral nutrition support in critically ill patients.With the development of the pharmaceutical industry, fat emulsion has formed a variety of different formulations, among which different types of fat emulsion have their own metabolic and body energy supply characteristics, and the application indications are also different. In addition to providing the supply of nutrients, the role of fat emulsion in anti-toxicity, immune regulation, anti-inflammatory, anti-shock, cardiopulmonary resuscitation and other aspects has gradually been discovered. This article reviews the existing evidence-based medical evidence and expounds the mechanism and therapeutic role of fat emulsion in the treatment of critically ill patients with poisoning. Its value in the treatment of critically ill patients with poisoning was discussed, and some references were provided for the application of non-nutritional functions of fat emulsion in the future.

A four-oil intravenous lipid emulsion improves markers of liver function, triglyceride levels and shortens length of hospital stay in adults: a systematic review and meta-analysis.

Clinical trials have reported that a four-oil intravenous lipid emulsion (SMOFlipid) play a positive role in immune function, but showed inconsistent outcomes compared to other lipid emulsions. A systematic review and meta-analysis was conducted to evaluate the effect of SMOFlipid on liver function, triglycerides (TG), inflammatory markers, and clinical outcomes in hospitalized adults after short-term use compared to others. A search of the PubMed, Medline, Embase, China National Knowledge Infrastructure, and Wanfang databases was performed to identify the included randomized controlled trials. Trials with adults who were administrated a short-term course of SMOFlipid were included. A meta-analysis on liver function markers, TG, inflammatory markers, and clinical outcomes was conducted. A total of 18 randomized controlled trials with 1188 patients were included. Compared to other lipid emulsions, SMOFlipid was associated with a significant reduction in ALT, AST, γ-glutamyltransferase, total bilirubin, TG, C-reactive protein and length of hospital stay. No effect on serum interleukin-6 levels or adverse events were observed. For adult patients, our meta-analysis indicated that SMOFlipid may be beneficial to the liver and prone to prevent hyperlipidemia. The SMOFlipid also shortened length of hospital stay.

Pharmacological preconditioning with intralipid in patients undergoing off-pump coronary artery bypass surgery.

Aims and Objectives: The objective of the study was to determine the preconditioning myocardial protective effects of intralipid (IL) in off-pump coronary artery bypass (OPCAB) surgery by measuring highly sensitive troponin T (hsTnT) and cardiac-specific creatine kinase (CK-MB) as markers of myocardial injury. Materials and Methods: : Thirty patients, scheduled to undergo elective OPCAB surgery, were randomly assigned to the IL group (n = 15) or control (C) group (n = 15); the IL group received an infusion of 20% IL 2 ml/kg, 30 min prior to revascularization and the control group received an equivalent volume of normal saline. Serum levels of hsTnT and CK-MB were measured before surgery and at 6 h, 24 h, 48 h, and 72 h postoperatively. Also, intraoperative hemodynamic parameters, inotrope use, ventilatory hours, ICU stay, postoperative left ventricular ejection fraction, postoperative lipid profile, renal and hepatic function tests were measured. Results: The hsTnT values at the 24 h, 48 h, and 72 h in IL group were significantly lower as compared with the control group. The decline in plasma levels of CK-MB mirrored the hsTnT levels post revascularization at 24 h and 48 h in the IL group compared with the control group; however, at 72 h, level was comparable in both the groups. None of the treated patients had abnormal lipid metabolism, deranged renal, and hepatic function. Conclusion: The study revealed Intralipid as a safe pharmacological preconditioning agent for OPCAB surgeries which can reduce the postischemic myocardial injury indicated by the reduction in postischemic cardiac enzymes hsTnT and CK-MB.

Fish oil supplementation with various lipid emulsions suppresses in vitro cytokine release in home parenteral nutrition patients: a crossover study.

Long-chain n-3 polyunsaturated fatty acids modulate immune cell functions. The primary objective of this study was to evaluate the impact of different lipid emulsions (LEs) with supplemented doses of fish oil (FO) on serum cytokine concentration and in vitro cytokine production in patients with intestinal failure on home parenteral nutrition (HPNPs). We hypothesized that FO supplementation would diminish lipopolysaccharide (LPS)-stimulated cytokine production. Twelve HPNPs receiving Smoflipid for at least 3 months were given FO (Omegaven) for a further 4 weeks. After this cycle, the patients were randomized to subsequently receive 1 cycle with Lipoplus and 1 cycle with ClinOleic for 6 weeks or vice versa plus 4 weeks of added Omegaven after each cycle in a crossover design. Comparison of the baseline LE regimens showed lower LPS-stimulated production of IL-1ß in the HPNPs on Lipoplus than on the Smoflipid and ClinOleic regimens, as well as lower IL-8 compared to the Smoflipid regimen. Omegaven reduced IL-8 concentration in serum under the Lipoplus regimen and diminished LPS-stimulated production of IL-1ß under the Smoflipid and ClinOleic. IL-6 and TNF-α production was depressed only in those on Smoflipid. Irrespective of the LE used, the HPNPs compared to the healthy controls showed higher IL-6, IL-8, and TNF-α concentrations in serum and LPS-stimulated production of IL-6 as well as lower n-6/n-3 long-chain polyunsaturated fatty acids in the erythrocyte phospholipids. LPS-stimulated production of IL-6 correlated negatively with the parenteral dose of eicosapentaenoic acid + docosahexaenoic acid. In conclusion, FO-supplemented parenteral nutrition suppresses in vitro cytokine production.

Effect of changing the lipid component of home parenteral nutrition in adults.

BACKGROUND: The effect of different lipid emulsions (LEs) within the parenteral nutrition (PN) regimen of adult home PN (HPN) patients is not clear. This study investigated the effect of changing adult HPN patients from a soybean oil based LE (Intralipid) to either a fish oil containing LE (providing n-3 fatty acids) (SMOFLipid) or an olive oil based LE (ClinOleic). METHODS: Thirty two adults receiving long-term HPN with Intralipid as the LE were transferred to receive either SMOFLipid (n = 13) or ClinOleic (n = 19) for 60 days. Liver function markers, cholesterol, triglycerides, a full profile of fatty acids, and several cytokines were measured at study entry and after 60 days. RESULTS: SMOFLipid did not affect liver function markers, blood lipids or plasma cytokines. ClinOleic lowered both gamma-glutamyltranspeptidase (P = 0.044) and interleukin-8 (P = 0.030) concentrations. Both LEs induced marked changes in the fatty acid profile of plasma. SMOFLipid resulted in significant decreases in the proportions of linoleic acid, several other n-6 fatty acids and the essential fatty acid (EFA) deficiency indicator mead acid and significant increases in the proportions of the n-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid. ClinOleic resulted in significant decreases in the proportions of some saturated fatty acids, linoleic acid, several n-6 fatty acids, all n-3 fatty acids and mead acid and a significant increase in the proportion of oleic acid. The ratio of mead to arachidonic acid in plasma was not altered by either SMOFLipid or ClinOleic. No patient had a mead acid to arachidonic acid ratio of >0.2, the cut-off used to indicate EFA deficiency. CONCLUSION: Both SMOFLipid and ClinOleic significantly alter the fatty acid profile of plasma in adult HPN patients previously using Intralipid. Neither LE induces EFA deficiency in these patients. SMOFLipid did not alter liver function markers or inflammation. In contrast, ClinOleic decreased some, though not all, markers of liver function and inflammation. SMOFLipid and ClinOleic may both be considered for use in adult HPN patients.

[Fat emulsion tolerance in preterm infants of different gestational ages in the early stage after birth].

OBJECTIVE: To investigate the fat emulsion tolerance in preterm infants of different gestational ages in the early stage after birth. METHODS: A total of 98 preterm infants were enrolled and divided into extremely preterm infant group (n=17), early preterm infant group (n=48), and moderate-to-late preterm infant group (n=33). According to the dose of fat emulsion, they were further divided into low- and high-dose subgroups. The umbilical cord blood and dried blood filter papers within 3 days after birth were collected. Tandem mass spectrometry was used to measure the content of short-, medium-, and long-chain acylcarnitines. RESULTS: The extremely preterm infant and early preterm infant groups had a significantly lower content of long-chain acylcarnitines in the umbilical cord blood and dried blood filter papers within 3 days after birth than the moderate-to-late preterm infant group (P<0.05), and the content was positively correlated with gestational age (P<0.01). On the second day after birth, the low-dose fat emulsion subgroup had a significantly higher content of short-, medium-, and long-chain acylcarnitines than the high-dose fat emulsion subgroup among the extremely preterm infants (P<0.05). In the early preterm infant and moderate-to-late preterm infant groups, there were no significant differences in the content of short-, medium-, and long-chain acylcarnitines between the low- and high-dose fat emulsion subgroups within 3 days after birth. CONCLUSIONS: Compared with moderate-to-late preterm infants, extremely preterm infants and early preterm infants have a lower capacity to metabolize long-chain fatty acids within 3 days after birth. Early preterm infants and moderate-to-late preterm infants may tolerate high-dose fat emulsion in the early stage after birth, but extremely preterm infants may have an insufficient capacity to metabolize high-dose fat emulsion.

Mechanisms Involved in Guiding the Preference for Fat Emulsion Differ Depending on the Concentration.

High-fat foods tend to be palatable and can cause addiction in mice via a reinforcing effect. However, mice showed preference for low fat concentrations that do not elicit a reinforcing effect in a two-bottle choice test with water as the alternative. This behavior indicates the possibility that the mechanism underlying fat palatability may differ depending on the dietary fat content. To address this issue, we examined the influences of the opioid system and olfactory and gustatory transductions on the intake and reinforcing effects of various concentrations of a dietary fat emulsion (Intralipid). We found that the intake and reinforcing effects of fat emulsion were reduced by the administration of an opioid receptor antagonist (naltrexone). Furthermore, the action of naltrexone was only observed at higher concentrations of fat emulsion. The intake and the reinforcing effects of fat emulsion were also reduced by olfactory and glossopharyngeal nerve transections (designated ONX and GLX, respectively). In contrast to naltrexone, the effects of ONX and GLX were mainly observed at lower concentrations of fat emulsion. These results imply that the opioid system seems to have a greater role in determining the palatability of high-fat foods unlike the contribution of olfactory and glossopharyngeal nerves.

Omega-3 Fatty Acid-Rich Parenteral Nutrition: Is It a Double-Edged Sword?

Parenteral nutrition (PN) has been strongly associated with intestinal failure-associated liver disease. Cholestasis, liver steatosis, and liver fibrosis are features of this liver injury, which can progress to end stage liver disease. Omega-3 fatty acid rich PN has been shown to alleviate cholestasis and steatosis. There have been reports although suggesting that it may not be able to arrest or reverse the progression to liver fibrosis. In this article, we develop a hypothesis of the mechanism of how Ω-3 fatty acid rich PN may influence the progression of fibrosis.

Safety and efficacy of parenteral fish oil-containing lipid emulsions in premature neonates.

OBJECTIVE: The aim of the study was to evaluate the safety and efficacy of fish oil-containing (FO) lipid emulsions that are rich in ω-3 fatty acids for parenteral nutrition in preterm neonates by using data retrieved from randomized controlled trials. METHODS: We performed a meta-analysis of 8 randomized controlled trials representing 483 premature neonates to compare FO with control (CO) lipid emulsions. RESULTS: This meta-analysis revealed that the levels of ω-3 fatty acids in the form of docosahexaenoic acid, eicosapentaenoic acid, and arachidonic acid (% of total fatty acids) in plasma were statistically higher in FO groups (mean difference [MD] -0.7%, 95% confidence interval [CI] -1.05 to -0.36, P < 0.001; MD -1.31%, 95% CI -1.40 to -1.21, P < 0.001). The differences were found in red blood cell (RBC) membranes. The levels of arachidonic acid (% of total fatty acids) as ω-6 fatty acid in plasma and red blood cell membranes were significantly lower in FO groups (MD 1.27%, 95% CI 1.12-1.42, P < 0.001) (MD 0.92%, 95% CI 0.12-1.72, P = 0.02). The mean body weight, serum level of bilirubin, triglycerides or C-reactive protein, all-cause mortality, and rate of lipid emulsion-associated complications were, however, not different between FO and CO groups. CONCLUSIONS: The level of docosahexaenoic acid is efficiently improved by FO lipid emulsions. The changes observed in eicosapentaenoic acid and arachidonic acid, and the associated safety issue, however, remain to be clarified. Any clinical benefit or detrimental effect of using FO in premature neonates cannot be demonstrated by the present study.

Impact of new-generation lipid emulsions on cellular mechanisms of parenteral nutrition-associated liver disease.

Parenteral nutrition (PN) is a life-saving nutritional support for a large population of hospitalized infants, and lipids make a substantial contribution to their energy and essential fatty acid (FA) needs. A challenge in the care of these infants is that their metabolic needs require prolonged PN support that increases the risk of PN-associated liver disease (PNALD). In recent years, the emergence of new parenteral lipid emulsions containing different source lipids and FA profiles has created nutritional alternatives to the first-generation, soybean oil-based lipid emulsion Intralipid. The limited U.S. introduction of the new-generation fish-oil emulsion Omegaven has generated promising results in infants with PNALD and spawned a renewed interest in how PN and lipid emulsions, in particular, contribute to this disease. Studies suggest that the lipid load and constituents, such as specific FAs, ratio of n-3 (ω-3) to n-6 (ω-6) long-chain polyunsaturated FAs, phytosterols, and vitamin E content, may be involved. There is an existing literature describing the molecular mechanisms whereby these specific nutrients affect hepatic metabolism and function via lipid and bile acid sensing nuclear receptors, such as peroxisome proliferator-activated receptor α, liver X receptor, and farnesoid X receptor, yet virtually no information as to how they interact and modulate liver function in the context of PN in pediatric patients or animal models. This article will review the recent development of parenteral lipid emulsions and their influence on PNALD and highlight some of the emerging molecular mechanisms that may explain the effects on liver function and disease.

Three short perioperative infusions of n-3 PUFAs reduce systemic inflammation induced by cardiopulmonary bypass surgery: a randomized controlled trial.

BACKGROUND: Fish oil (FO) has antiinflammatory effects, which might reduce systemic inflammation induced by a cardiopulmonary bypass (CPB). OBJECTIVE: We tested whether perioperative infusions of FO modify the cell membrane composition, inflammatory responses, and clinical course of patients undergoing elective coronary artery bypass surgery. DESIGN: A prospective randomized controlled trial was conducted in cardiac surgery patients who received 3 infusions of 0.2 g/kg FO emulsion or saline (control) 12 and 2 h before and immediately after surgery. Blood samples (7 time points) and an atrial biopsy (during surgery) were obtained to assess the membrane incorporation of PUFAs. Hemodynamic data, catecholamine requirements, and core temperatures were recorded at 10-min intervals; blood triglycerides, nonesterified fatty acids, glucose, lactate, inflammatory cytokines, and carboxyhemoglobin concentrations were measured at selected time points. RESULTS: Twenty-eight patients, with a mean ± SD age of 65.5 ± 9.9 y, were enrolled with no baseline differences between groups. Significant increases in platelet EPA (+0.86%; P = 0.0001) and DHA (+0.87%; P = 0.019) were observed after FO consumption compared with at baseline. Atrial tissue EPA concentrations were higher after FO than after control treatments (+0.5%; P < 0.0001). FO did not significantly alter core temperature but decreased the postoperative rise in IL-6 (P = 0.018). Plasma triglycerides increased transiently after each FO infusion. Plasma concentrations of glucose, lactate, and blood carboxyhemoglobin were lower in the FO than in the control group on the day after surgery. Arrhythmia incidence was low with no significant difference between groups. No adverse effect of FO was detected. CONCLUSIONS: Perioperative FO infusions significantly increased PUFA concentrations in platelet and atrial tissue membranes within 12 h of the first FO administration and decreased biological and clinical signs of inflammation. These results suggest that perioperative FO may be beneficial in elective cardiac surgery with CPB.

Rapid enrichment of cell phospholipids in long-chain polyunsaturated ω-3 fatty acids after a bolus intravenous injection of a medium-chain triacylglycerol: fish oil emulsion in humans.

The present review aims at highlighting the use of a recently developed medium-chain triacylglycerol:fish oil (MCT:FO) emulsion for the rapid and sustained enrichment of long-chain polyunsaturated ω-3 fatty acids in cell phospholipids. Preclinical in vitro, in vivo, and ex vivo experiments are briefly considered with emphasis on the changes in the fatty acid pattern of cell phospholipids in several organs, the partial correction of liver steatosis, and the cardiovascular modification of cationic and functional variables observed in ω-3-depleted rats examined 60-120 minutes after a bolus intravenous (IV) injection (1.0 mL) of the MCT:FO emulsion. The clinical findings collected in healthy male volunteers before or after the bolus IV injection (50.0 mL) of either the MCT:FO emulsion or a control medium-chain triacylglycerol:long-chain triacylglycerol emulsion are also reviewed, with emphasis on the rapid (within 60 minutes) and sustained (up to 2-3 days) enrichment of platelet and white blood cell phospholipids in long-chain polyunsaturated ω-3 fatty acids and hemostatic safety of the present procedure proposed as a tool for the rapid prevention or correction of metabolic and functional disturbances in humans with a relative deficiency in such ω-3 fatty acids.

A mixed (long- and medium-chain) triglyceride lipid emulsion extracts local anesthetic from human serum in vitro more effectively than a long-chain emulsion.

BACKGROUND: Lipid emulsion infusion reverses cardiac toxicity of local anesthetics. The predominant effect is likely creation of a "lipid sink." This in vitro study determined the extent to which Intralipid® (Fresenius Kabi, Uppsala, Sweden) and Lipofundin® (B. Braun Melsungen AG, Melsungen, Germany) sequester anesthetics from serum, and whether it varies with pH. METHODS: Bupivacaine, ropivacaine, and mepivacaine were added to human drug-free serum (pH 7.4) at 10 µg/ml. The lipid emulsions were added, and the mixture shaken and incubated at 37°C. Lipid was removed by ultracentrifugation and drug remaining in the serum measured. Additional experiments were performed using 100 µg/ml bupivacaine and at pH 6.9. RESULTS: Lipofundin® extracted all three anesthetics to a greater extent than Intralipid® (34.7% vs..22.3% for bupivacaine, 25.8% vs..16.5% for ropivacaine, and 7.3% vs..4.7% for mepivacaine). By increasing either concentration of bupivacaine or lipid, there was an increase in drug extraction from serum. Adjusting the pH to 6.9 had no statistically significant effect on the percentage of bupivacaine sequestered. CONCLUSIONS: Bupivacaine, ropivacaine, and mepivacaine were sequestered to an extent consistent with their octanol:water partition constants (logP). In contrast with previous studies of extraction of lipids from buffer solutions, an emulsion containing 50% each of medium- and long-chain triglycerides extracted local anesthetics to a greater extent from human serum than one containing exclusively long-chain triglycerides, calling into question recent advanced cardiac life support guidelines for resuscitation from anesthetic toxicity that specify use of a long-chain triglyceride. The current data also do not support recent recommendations to delay administration until pH is normalized.

Effects of moderate exercise on VLDL1 and Intralipid kinetics in overweight/obese middle-aged men.

Prior moderate exercise reduces plasma triglyceride (TG)-rich lipoprotein concentrations, mainly in the large very low-density lipoprotein (VLDL1) fraction, but the mechanism responsible is unclear. We investigated the effects of brisk walking on TG-rich lipoprotein kinetics using a novel method. Twelve overweight/obese middle-aged men underwent two kinetic studies, involving infusion of Intralipid to block VLDL1 catabolism, in random order. On the afternoon prior to infusion, subjects either walked on a treadmill for 2 h at ∼50% maximal oxygen uptake or performed no exercise. Multiple blood samples were taken during and after infusion for separation of Intralipid (S(f) 400) and VLDL1 (S(f) 60-400). VLDL1-TG and -apoB production rates were calculated from their linear rises during infusion; fractional catabolic rates (FCR) were calculated by dividing linear rises by fasting concentrations. Intralipid-TG FCR was determined from the postinfusion exponential decay. Exercise reduced fasting VLDL1-TG concentration by 30% (P = 0.007) and increased TG enrichment of VLDL1 particles [30% decrease in cholesteryl ester (CE)/TG ratio (P = 0.007); 26% increase in TG/apoB ratio (P = 0.059)]. Exercise also increased VLDL1-TG, VLDL1-apoB, and Intralipid-TG FCRs by 82, 146, and 43%, respectively (all P < 0.05), but had no significant effect on VLDL1-TG or -apoB production rates. The exercise-induced increase in VLDL1-apoB FCR correlated strongly with the exercise-induced changes in VLDL1 CE/TG (r = -0.659, r = 0.020) and TG/apoB (r = 0.785, P = 0.002) ratios. Thus, exercise-induced reductions in VLDL1 concentrations are mediated by increased catabolism, rather than reduced production, which may be facilitated by compositional changes to VLDL1 particles that increase their affinity for clearance from the circulation.

Olive oil-based intravenous lipid emulsion in pediatric patients undergoing bone marrow transplantation: a short-term prospective controlled trial.

BACKGROUND & AIMS: Parenteral nutrition (PN) is an important component of the supportive care of children undergoing bone marrow transplantation (BMT). The study aimed to assess short-term safety and metabolic effects of an olive oil-based (OO) lipid emulsion compared with a MCT/LCT (M/L) emulsion in the clinical setting of pediatric BMT. METHODS: Twenty-eight pediatric BMT patients (age 1-18 years) expected to need PN support for at least 2 weeks, were prospectively enrolled and randomly assigned to receive either OO or M/L lipid emulsions within PN. Clinical and routine laboratory parameters, plasma fatty acids profile, vitamin E and peroxidation status were recorded at baseline and after 14 days of PN. RESULTS: No significant differences were found for hematological parameters, liver enzymes, vitamins, plasma peroxidation status, percentage and time to engraftment. Taking into consideration the baseline fatty acids levels, the OO group showed higher oleic acid (p=0.012), linoleic (p=0.012) and arachidonic acid (p=0.002) enrichment but similar eicosapentanoic and docosahexanoic acids levels compared to the M/L group at day 14. Cholesterol levels decreased significantly in the OO group after 14 days on PN (p=0.017). CONCLUSIONS: OO lipid emulsion was well tolerated, maintained essential fatty acids and peroxidation status, and generated a favorable plasma lipid profile. In this study short-term use of OO intravenous lipid emulsions was safe in children who needed PN support during BMT.

Stimulation of incretin secretion by dietary lipid: is it dose dependent?

After the ingestion of nutrients, secretion of the incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) by the enteroendocrine cells increases rapidly. Previous studies have shown that oral ingestion of fat stimulates secretion of both incretins; however, it is unclear whether there is a dose-dependent relationship between the amount of lipid ingested and the secretion of the hormones in vivo. Recently, we found a higher concentration of the incretin hormones in intestinal lymph than in peripheral or portal plasma. We therefore used the lymph fistula rat model to test for a dose-dependent relationship between the secretion of GIP and GLP-1 and dietary lipid. Under isoflurane anesthesia, the major mesenteric lymphatic duct of male Sprague-Dawley rats was cannulated. Each animal received a single, intraduodenal bolus of saline or varying amounts of the fat emulsion Liposyn II (0.275, 0.55, 1.1, 2.2, and 4.4 kcal). Lymph was continuously collected for 3 h and analyzed for triglyceride, GIP, and GLP-1 content. In response to increasing lipid calories, secretion of triglyceride, GIP, and GLP-1 into lymph increased dose dependently. Interestingly, the response to changes in intraluminal lipid content was greater in GLP-1- than in GIP-secreting cells. The different sensitivities of the two cell types to changes in intestinal lipid support the concept that separate mechanisms may underlie lipid-induced GIP and GLP-1 secretion. Furthermore, we speculate that the increased sensitivity of GLP-1 to intestinal lipid content reflects the hormone's role in the ileal brake reflex. As lipid reaches the distal portion of the gut, GLP-1 is secreted in a dose-dependent manner to reduce intestinal motility and enhance proximal fat absorption.

Vitamin A and vitamin E isoforms stability and peroxidation potential of all-in-one admixtures for parenteral nutrition.

BACKGROUND: In all-in-one admixtures (AIOs), vitamins can be degraded and lipid can be peroxidized by light exposure, oxygen action, and multiple chemical interactions. AIM: We investigated the impact of three commercial lipid emulsions and two multivitamin preparations on vitamin A and vitamin E chemical stability and lipid peroxidation potential of AIOs. METHODS: A soybean oil (Soy), soybean/medium-chain triacylglycerol oil (MCT), and olive/soybean oil (Olive)-based emulsion (all 20%), and a lyophilized (Lyo) and emulsified (Emu) multivitamin compounds, were tested. Two AIOs for each lipid emulsion were prepared, the former with Lyo and the latter with Emu. The concentrations of retinol palmitate, alpha-gamma-delta-tocopherol, and malondialdehyde were analyzed in AIOs, immediately (T0) and 24 hours (T24) after compounding. RESULTS: Retinol palmitate, and alpha- and gamma-tocopherol were more stable in MCT-AIOs than in both Soy-AIOs and Olive-AIOs (p < 0.013; p < 0.001 respectively). Furthermore alpha-tocopherol was more stable in Lyo-AIOs than in Emu-AIOs (p < 0.004). Malondialdehyde (MDA) increased differently among the admixtures; however the concentrations were similar in all AIOs at T24. CONCLUSIONS: The differences in retinol palmitate stability were due both to lipid emulsions per se and to interaction between lipid emulsions and multivitamin preparations. The alpha-gamma-tocopherol stability depended on both lipid emulsions and multivitamin preparations. In tested AIOs there was a different degradation rate of fat-soluble vitamins to keep the same lipid peroxidation level, since MDA concentrations at T24 were similar among AIOs.

Immune modulation by parenteral lipid emulsions.

Total parenteral nutrition is the final option for nutritional support of patients with severe intestinal failure. Lipid emulsions constitute the main source of fuel calories and fatty acids (FAs) in parenteral nutrition formulations. However, adverse effects on patient outcomes have been attributed to the use of lipids, mostly in relation to impaired immune defenses and altered inflammatory responses. Over the years, this issue has remained in the limelight, also because technical advances have provided no safeguard against the most daunting problems, ie, infectious complications. Nevertheless, numerous investigations have failed to produce a clear picture of the immunologic characteristics of the most commonly used soybean oil-derived lipid emulsions, although their high content of n-6 polyunsaturated FAs (PUFAs) has been considered a drawback because of their proinflammatory potential. This concern initiated the development of emulsions in which part of the n-6 FA component is replaced by less bioactive FAs, such as coconut oil (rich in medium-chain saturated FAs) or olive oil (rich in the n-9 monounsaturated FA oleic acid). Another approach has been to use fish oil (rich in n-3 PUFA), the FAs of which have biological activities different from those of n-6 PUFAs. Recent studies on the modulation of host defenses and inflammation by fish-oil emulsions have yielded consistent data, which indicate that these emulsions may provide a tool to beneficially alter the course of immune-mediated conditions. Although most of these lipids have not yet become available on the US market, this review synthesizes available information on immunologic characteristics of the different lipids that currently can be applied via parenteral nutrition support.

Enhancing parenteral nutrition therapy for the neonate.

The neonate receiving parenteral nutrition (PN) therapy requires a physiologically appropriate solution in quantity and quality given according to a timely, cost-effective strategy. Maintaining tissue integrity, metabolism, and growth in a neonate is challenging. To support infant growth and influence subsequent development requires critical timing for nutrition assessment and intervention. Providing amino acids to neonates has been shown to improve nitrogen balance, glucose metabolism, and amino acid profiles. In contrast, supplying the lipid emulsions (currently available in the United States) to provide essential fatty acids is not the optimal composition to help attenuate inflammation. Recent investigations with an omega-3 fish oil IV emulsion are promising, but there is need for further research and development. Complications from PN, however, remain problematic and include infection, hepatic dysfunction, and cholestasis. These complications in the neonate can affect morbidity and mortality, thus emphasizing the preference to provide early enteral feedings, as well as medication therapy to improve liver health and outcome. Potential strategies aimed at enhancing PN therapy in the neonate are highlighted in this review, and a summary of guidelines for practical management is included.