The role of ω-3 fatty acid supplemented parenteral nutrition in critical illness in adults: a systematic review and meta-analysis. Crit Care Med. 2013;41:307-316. [PMID: 23128380 DOI: 10.1097/CCM.0b013e3182657578]

[Immunomodulation by nutritional intervention in critically ill patients]

Critically ill patients often suffer from a complex and severe immunological dysfunction. The differentiation and function of human immune cells are fundamentally controlled through metabolic processes. New concepts of immunonutrition therefore try to use enteral and parenteral nutrition to positively impact on the immune function of intensive care unit patients. This review article concisely presents the currently available evidence on the commonly used isolated supplements (anti-oxidative substances, amino acids, essential fatty acids) and difficulties related to their clinical use. The second part presents new and more comprehensive concepts of immunonutrition to influence the intestinal microbiome and to modulate the macronutrient composition. Immunonutrition of critically ill patients bears enormous potential and could become a valuable clinical tool for modulation of the immunometabolism of intensive care unit patients.

Nutritional Support with Omega-3 Fatty Acids in Burn Patients: A Systematic Review with Meta-Analysis of Randomized Controlled Trials

Background: In burn patients, the profound effect of nutritional support on improved wound healing and a reduced rate of hospitalization and mortality has been documented. Fish oil as a primary source of omega-3 fatty acids in nutritional support may attenuate the inflammatory response and enhance immune function; however, unclear effects on the improvement of clinical outcomes in burn patients remain. Methods: The systematic literature review was conducted by searching the electronic databases: Cochrane Library, PubMed, ScienceDirect, and Scopus to assess the randomized controlled trials of nutritional support with omega-3 fatty acids compared to control diets in patients that presented with burns from any causes. Results: Seven trials were included in this meta-analysis. We found no significant differences in length of stay (LOS) (p = 0.59), mortality (p = 0.86), ventilation days (p = 0.16), gastrointestinal complications—e.g., constipation and diarrhea (p = 0.73)—or infectious complications—e.g., pneumonia and sepsis (p = 0.22)—between the omega-3-fatty-acid-receiving group and the control/other diets group. Conclusions: We did not find a benefit of omega-3 support in reducing the various complications, mortality and LOS in burn patients. Further studies are necessary to find the effect of nutritional support with omega-3 fatty acids over low-fat diets in this population.

Effects of fish oil-containing nutrition supplementation in adult sepsis patients: a systematic review and meta-analysis

BACKGROUND

Sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection. Although fish oil has been used as an immunonutritional preparations for the treatment of sepsis patients, there is still controversy as to whether it is beneficial to them. We systematically reviewed published clinical trial data to evaluate the effectiveness of fish oil-containing nutrition supplementation in sepsis patients.

METHODS

A systematic search was undertaken in PubMed, Embase, Chinese Biomedicine Database, the Cochrane Library and the China Knowledge Resource Integrated Database to obtain clinical controlled trails. RCTs on nutrition therapy containing fish oil among adult sepsis patients were selected for analysis in comparison with routine therapy.

RESULTS

Twenty-five published trials were included in the meta-analysis. Fish oil-containing nutrition supplementation reduced the mortality compared with the control group (relative risk (RR) 0.74, I ² = 0%). Fish oil also shortened the ICU stay (MD -3.57 days; 95% CI -4.54, -2.59; p<0.00001; I ² = 76%), hospital stay (MD -9.92 days; 95% CI -15.37, -4.46; p = 0.0004; I ² = 91%) and the duration of mechanical ventilation support (MD -2.26; 95% CI -4.27, -0.26; p = 0.03; I ² = 83%). A subgroup analysis based on the route of administration revealed that parenteral administration of fish oil could reduce mortality in septic patients (RR =0.68, I ² = 0%), but no significant difference in mortality was observed in the fish oil group administered by enteral route (RR = 0.80, I ² = 0%). No statistically significant publication biases were detected for the above clinical endpoints (p>0.05).

CONCLUSIONS

Parenteral nutrition containing fish oil could significantly decrease mortality in sepsis patients while enteral administration could not. Fish oil-containing nutrition supplementation.

Amyloid fibril formation by casein and fatty acid composition in breast milk of mastitis patients

Mastitis can cause changes in the nutrient composition of breast milk, which may be harmful to both newborns and lactating mothers. In this study we preliminarily evaluated amyloid fibrils formation by casein and fatty acids (FA), as well as their potential relation with each other in the breast milk of mastitis patients. Six healthy volunteers and six mastitis patients were recruited from the Maternal and Child Health Care Hospital in Changchun were enrolled. Amyloid fibril content was assessed by thioflavin T fluorescence analysis, transmission electron microscope, circular dichroism, and proton nuclear magnetic resonance. FA contents were measured by gas chromatography. Healthy breast milk contained no amyloid fibrils but inflammatory breast milk did. Several FAs (hendecanoic acid, myristolenic acid, pentadecenoic acid, eicosatrienoic acid) differed significantly between the two groups (p < .05). The concentrations of the eicosatrienoic acid and eleven carbonic acids in the inflammatory groups were lower than those in the healthy groups, but the myristolenic acid and pentadecenoic acid were the opposite trend. Early detection of amyloid fibrils should be performed in lactating mothers with mastitis. Changes in FAs may reflect the importance of abnormal metabolism in amyloid fibril formation. PRACTICAL APPLICATIONS: The work preliminarily clarified the relationship between inflammation, fibril content, and fatty acid (FA) composition in breast milk. Healthy milk contained no amyloid fibril formed by casein but the inflammatory milk did. FAs were also significantly different between the two groups. Thus, an early determination of amyloid fibrils in milk should be considered for lactating women with mastitis to avoid the further malignant development. Additionally, the changes in FAs may reflect the importance of abnormal metabolism and oxidative pathways in amyloid fibril formation in the breast. Therefore, this study provided foundations for further investigation on the association between inflammation, fibril content and FA composition in breast milk.

Commentary on "Guidelines for the provision of nutrition support therapy in the adult critically ill patient: The American Society for Parenteral and Enteral Nutrition"

Robert G. Martindale has received honoraria from Baxter, Fresenius Kabi, and Nestle, and acted as an advisory board member for Nestle. Stanislaw Klek has received speaker's honoraria from Baxter, Braun, Fresenius Kabi, Nestle, Nutricia, Shire, and Vipharm, and acted as an advisory board member for Fresenius Kabi, Shire, and Tracheron. Zudin Puthucheary has received honoraria for consultancy and speaker fees from Faraday Pharmaceuticals, Baxter, Fresenius Kabi, Nutricia, and Nestle. Martin D. Rosenthal has reported to be on the speaking bureau for Fresenius Kabi, Nestle, Baxter, and Abbott, and has received honoraria from these companies. This article is protected by copyright. All rights reserved.

Omega-6 sparing effects of parenteral lipid emulsions-an updated systematic review and meta-analysis on clinical outcomes in critically ill patients

BACKGROUND

Parenteral lipid emulsions in critical care are traditionally based on soybean oil (SO) and rich in pro-inflammatory omega-6 fatty acids (FAs). Parenteral nutrition (PN) strategies with the aim of reducing omega-6 FAs may potentially decrease the morbidity and mortality in critically ill patients.

METHODS

A systematic search of MEDLINE, EMBASE, CINAHL and CENTRAL was conducted to identify all randomized controlled trials in critically ill patients published from inception to June 2021, which investigated clinical omega-6 sparing effects. Two independent reviewers extracted bias risk, treatment details, patient characteristics and clinical outcomes. Random effect meta-analysis was performed.

RESULTS

1054 studies were identified in our electronic search, 136 trials were assessed for eligibility and 26 trials with 1733 critically ill patients were included. The median methodologic score was 9 out of 14 points (95% confidence interval [CI] 7, 10). Omega-6 FA sparing PN in comparison with traditional lipid emulsions did not decrease overall mortality (20 studies; risk ratio [RR] 0.91; 95% CI 0.76, 1.10; p = 0.34) but hospital length of stay was substantially reduced (6 studies; weighted mean difference [WMD] - 6.88; 95% CI - 11.27, - 2.49; p = 0.002). Among the different lipid emulsions, fish oil (FO) containing PN reduced the length of intensive care (8 studies; WMD - 3.53; 95% CI - 6.16, - 0.90; p = 0.009) and rate of infectious complications (4 studies; RR 0.65; 95% CI 0.44, 0.95; p = 0.03). When FO was administered as a stand-alone medication outside PN, potential mortality benefits were observed compared to standard care.

CONCLUSION

Overall, these findings highlight distinctive omega-6 sparing effects attributed to PN. Among the different lipid emulsions, FO in combination with PN or as a stand-alone treatment may have the greatest clinical impact. Trial registration PROSPERO international prospective database of systematic reviews (CRD42021259238).

Summary of Proceedings and Expert Consensus Statements From the International Summit "Lipids in Parenteral Nutrition"

BACKGROUND

The 2018 Lipids in Parenteral Nutrition summit involved a panel of experts in clinical nutrition, lipid metabolism, and pharmacology, to assess the current state of knowledge and develop expert consensus statements regarding the use of intravenous lipid emulsions in various patient populations and clinical settings. The main purpose of the consensus statements is to assist healthcare professionals by providing practical guidance on common clinical questions related to the provision of lipid emulsions as part of parenteral nutrition (PN).

METHODS

The summit was designed to allow interactive discussion and consensus development. The resulting consensus statements represent the collective opinion of the members of the expert panel, which was informed and supported by scientific evidence and clinical experience.

RESULTS

The current article summarizes the key discussion topics from the summit and provides a set of consensus statements designed to complement existing evidence-based guidelines. Lipid emulsions are a major component of PN, serving as a condensed source of energy and essential fatty acids. In addition, lipids modulate a variety of biologic functions, including inflammatory and immune responses, coagulation, and cell signaling. A growing body of evidence suggests that lipid emulsions containing ω-3 fatty acids from fish oil confer important clinical benefits via suppression of inflammatory mediators and activation of pathways involved in the resolution of inflammation.

CONCLUSIONS

This article provides a set of expert consensus statements to complement formal PN guideline recommendations.

Lipid Use in Hospitalized Adults Requiring Parenteral Nutrition

In hospitalized patients, lipid emulsions are an integral part of balanced parenteral nutrition. Traditionally, a single lipid source, soybean oil, has been given to patients and was usually regarded as just a source of energy and to prevent essential fatty-acid deficiency. However, mixtures of different lipid emulsions have now become widely available, including mixtures of soybean oil, medium-chain triglycerides, olive oil, and fish oil. Fish oil is high in the ω-3 polyunsaturated fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). There is a growing body of evidence that these ω-3 fatty acids can exert beneficial immunomodulatory, anti-inflammatory, and inflammation-resolution effects across a wide range of patient groups including surgical, cancer, and critically ill patients. At least in part, these effects are realized via potent specialized pro-resolution mediators (SPMs). Moreover, parenteral nutrition including ω-3 fatty acids can result in additional clinical benefits over the use of standard lipid emulsions, such as reductions in infection rates and length of hospital and intensive care unit stay. Clinical and experimental evidence is reviewed regarding lipid emulsion use in a variety of hospitalized patient groups, including surgical, critically ill, sepsis, trauma, and acute pancreatitis patients. Practical aspects of lipid emulsion use in critically ill patients are also considered, such as how to determine and fulfill energy expenditure, how and when to consider parenteral nutrition, duration of infusion, and safety monitoring.

Omega-3 fatty acid-containing parenteral nutrition in ICU patients: systematic review with meta-analysis and cost-effectiveness analysis

Background

Omega-3 (ω-3) fatty acid (FA)-containing parenteral nutrition (PN) is associated with significant improvements in patient outcomes compared with standard PN regimens without ω-3 FA lipid emulsions. Here, we evaluate the impact of ω-3 FA-containing PN versus standard PN on clinical outcomes and costs in adult intensive care unit (ICU) patients using a meta-analysis and subsequent cost-effectiveness analysis from the perspective of a hospital operating in five European countries (France, Germany, Italy, Spain, UK) and the US.

Methods

We present a pharmacoeconomic simulation based on a systematic literature review with meta-analysis. Clinical outcomes and costs comparing ω-3 FA-containing PN with standard PN were evaluated in adult ICU patients eligible to receive PN covering at least 70% of their total energy requirements and in the subgroup of critically ill ICU patients (mean ICU stay > 48 h). The meta-analysis with the co-primary outcomes of infection rate and mortality rate was based on randomized controlled trial data retrieved via a systematic literature review; resulting efficacy data were subsequently employed in country-specific cost-effectiveness analyses.

Results

In adult ICU patients, ω-3 FA-containing PN versus standard PN was associated with significant reductions in the relative risk (RR) of infection (RR 0.62; 95% CI 0.45, 0.86; p = 0.004), hospital length of stay (HLOS) (− 3.05 days; 95% CI − 5.03, − 1.07; p = 0.003) and ICU length of stay (LOS) (− 1.89 days; 95% CI − 3.33, − 0.45; p = 0.01). In critically ill ICU patients, ω-3 FA-containing PN was associated with similar reductions in infection rates (RR 0.65; 95% CI 0.46, 0.94; p = 0.02), HLOS (− 3.98 days; 95% CI − 6.90, − 1.06; p = 0.008) and ICU LOS (− 2.14 days; 95% CI − 3.89, − 0.40; p = 0.02). Overall hospital episode costs were reduced in all six countries using ω-3 FA-containing PN compared to standard PN, ranging from €-3156 ± 1404 in Spain to €-9586 ± 4157 in the US.

Conclusion

These analyses demonstrate that ω-3 FA-containing PN is associated with statistically and clinically significant improvement in patient outcomes. Its use is also predicted to yield cost savings compared to standard PN, rendering ω-3 FA-containing PN an attractive cost-saving alternative across different health care systems.

Study registration

PROSPERO CRD42019129311.

Clinical Nutrition of Critically Ill Patients in the Context of the Latest ESPEN Guidelines

The group of patients most frequently in need of nutritional support are intensive care patients. This year (i.e., 2019), new European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines of clinical nutrition in intensive care were published, updating and gathering current knowledge on the subject of this group of patients. Planning the right nutritional intervention is often a challenging task involving the necessity of the choice of the enteral nutrition (EN) or parenteral nutrition (PN) route of administration, time of initiation, energy demand, amino acid content and demand as well as the use of immunomodulatory nutrition. The aim of this study was to specify and discuss the basic aspects of the clinical nutrition of critically ill patients recommended by ESPEN guidelines. Clinical nutrition in intensive care seems to be the best-studied type of nutritional intervention. However, meta-analyses and clinical studies comparing EN and PN and their impact on the prognosis of the intensive care patients showed ambiguous results. The nutritional interventions, starting with EN, should be initiated within 24-48 h whereas PN, if recommended, should be implemented within 3-7 days. The recommended method of calculation of the energy demand is indirect calorimetry, however, there are also validated equations used worldwide in everyday practice. The recommended protein intake in this group of patients and the results of insufficient or too high supply was addressed. In light of the concept of immunomodulatory nutrition, the use of appropriate amino acid solutions and lipid emulsion that can bring a positive effect on the modulation of the immune response was discussed.

Antioxidant and Cardioprotective Effects of EPA on Early Low-Severity Sepsis through UCP3 and SIRT3 Upholding of the Mitochondrial Redox Potential

Sepsis still causes death, often through cardiac failure and mitochondrial dysfunction. Dietary ω3 polyunsaturated fatty acids are known to protect against cardiac dysfunction and sepsis lethality. This study set out to determine whether early low-severity sepsis alters the cardiac mitochondrial function in animals fed a Western-type diet and whether dietary eicosapentaenoic acid (EPA) administration protects the myocardium against the deleterious effects of sepsis and if so to seek possible mechanisms for its effects. Rats were divided into two groups fed either an ω3 PUFA-deficient diet (“Western diet,” DEF group) or an EPA-enriched diet (EPA group) for 5 weeks. Each group was subdivided into two subgroups: sham-operated rats and rats subjected to cecal ligation and puncture (CLP). In vivo cardiac mechanical function was examined, and mitochondria were harvested to determine their functional activity. Oxidative stress was evaluated together with several factors involved in the regulation of reactive oxygen species metabolism. Sepsis had little effect on cardiac mechanical function but strongly depressed mitochondrial function in the DEF group. Conversely, dietary EPA greatly protected the mitochondria through a decreased oxidative stress of the mitochondrial matrix. The latter was probably due to an increased uncoupling protein-3 expression, already seen in the sham-operated animals. CLP rats in the EPA group also displayed increased mitochondrial sirtuin-3 protein expression that could reinforce the upholding of oxidative phosphorylation. Dietary EPA preconditioned the heart against septic damage through several modifications that protect mitochondrial integrity. This preconditioning can explain the cardioprotective effect of dietary EPA during sepsis.

Effects of a metabolic optimized fast track concept (MOFA) on bowel function and recovery after surgery in patients undergoing elective colon or liver resection: a randomized controlled trial

Background

Enhanced recovery after surgery programs (ERAS) using thoracic epidural anesthesia and perioperative patient conditioning with omega-3 fatty acids (n3FA), glucose control (GC) and on-demand fluid therapy, respectively, showed beneficial effects. In the MOFA- study these components were used together in patients undergoing colon or liver surgery. We hypothesized that the use of a perioperative MOFA program improves intestine function represented as time to the first postoperative bowel movement in adult patients compared to standard ERAS.

Methods

After BfArM and IRB approval 100 patients were enrolled in this prospective randomized controlled trial. All patients received ERAS therapy (control). In addition, the MOFA group received 0.2 g/kg fish oil (Omegaven®), preoperatively, followed by a 48 h continuous infusion of 0.2 g/kg/d n3FA; and GC was kept below < 8 mmol/L. Pre- and postoperatively energy drinks were administered.

Results

As compared to control group the MOFA concept resulted in an earlier onset of flatulence by 14 h (46.6 ± 25.7, 32.0 ± 17.9, p = 0.030, hours, control vs. MOFA, respectively). Effects on onset of bowel movement were not observed (74.5 ± 30.4, 66.4 ± 29.2, p = 0.163, hours, control vs. MOFA, respectively). The disease severity (SAPS II score; p = 0.720) as well as deployment of resources (TISS 28 score, p = 0.709) did not differ between groups. No statistic significant difference between MOFA and control group regarding inflammation, impairment of coagulation, length of hospital stay or incidence of postoperative surgical complications were observed.

Conclusions

The MOFA concept did not result in an improvement of intestine function or faster recovery after elective colon or liver surgery compared to standard ERAS therapy. Omega-3 fatty acids showed no impairment of coagulation or improved resolution of inflammation. Further trials in a larger patient collective are needed to investigate potential beneficial effects of omega-3 fatty acids in abdominal surgery.

Trial registration

This trial was prospectively registered at the European Union Clinical Trials Register (EuDraCT 2005–004814-33, date: 10-05-2005, https://www.clinicaltrialsregister.eu/ctr-search/search?query=2005-004814-33+).

Electronic supplementary material

The online version of this article (10.1186/s12871-019-0823-6) contains supplementary material, which is available to authorized users.

Clinical Nutrition in Critical Care Medicine - Guideline of the German Society for Nutritional Medicine (DGEM)

PURPOSE

Enteral and parenteral nutrition of adult critically ill patients varies in terms of the route of nutrient delivery, the amount and composition of macro- and micronutrients, and the choice of specific, immune-modulating substrates. Variations of clinical nutrition may affect clinical outcomes. The present guideline provides clinicians with updated consensus-based recommendations for clinical nutrition in adult critically ill patients who suffer from at least one acute organ dysfunction requiring specific drug therapy and/or a mechanical support device (e.g., mechanical ventilation) to maintain organ function.

METHODS

The former guidelines of the German Society for Nutritional Medicine (DGEM) were updated according to the current instructions of the Association of the Scientific Medical Societies in Germany (AWMF) valid for a S2k-guideline. According to the S2k-guideline classification, no systematic review of the available evidence was required to make recommendations, which, therefore, do not state evidence- or recommendation grades. Nevertheless, we considered and commented the evidence from randomized-controlled trials, meta-analyses and observational studies with adequate sample size and high methodological quality (until May 2018) as well as from currently valid guidelines of other societies. The liability of each recommendation was described linguistically. Each recommendation was finally validated and consented through a Delphi process.

RESULTS

In the introduction the guideline describes a) the pathophysiological consequences of critical illness possibly affecting metabolism and nutrition of critically ill patients, b) potential definitions for different disease phases during the course of illness, and c) methodological shortcomings of clinical trials on nutrition. Then, we make 69 consented recommendations for essential, practice-relevant elements of clinical nutrition in critically ill patients. Among others, recommendations include the assessment of nutrition status, the indication for clinical nutrition, the timing and route of nutrient delivery, and the amount and composition of substrates (macro- and micronutrients); furthermore, we discuss distinctive aspects of nutrition therapy in obese critically ill patients and those treated with extracorporeal support devices.

CONCLUSION

The current guideline provides clinicians with up-to-date recommendations for enteral and parenteral nutrition of adult critically ill patients who suffer from at least one acute organ dysfunction requiring specific drug therapy and/or a mechanical support device (e.g., mechanical ventilation) to maintain organ function. The period of validity of the guideline is approximately fixed at five years (2018-2023).

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.

Outcomes with perioperative fat emulsions containing omega-3 fatty acid: A meta-analysis of randomized controlled trials

PURPOSE

Results of a meta-analysis of data from clinical studies comparing patient outcomes and hospital length of stay (LOS) in surgical patients receiving fish oil (FO)-containing i.v. fat emulsions (IVFEs) versus non-FO-containing IVFEs are presented.

METHODS

Computerized searches of the MEDLINE, Embase, and Coch rane CENTRAL databases were performed in August 2014 to identify English-language articles on randomized controlled trials (RCTs) comparing FO-containing and non-FO-containing IVFEs in adult surgical patients receiving parenteral nutrition. Selected articles were analyzed for methodological and publication bias and study heterogeneity (I² statistic).

RESULTS

Data from 19 RCTs (total n = 1,167) were included in the meta-analysis. Compared with use of non-FO-containing IVFEs (products based in soybean oil [SO], medium-chain triglycerides, or olive oil), use of FO-containing IVFEs was associated with reduced infectious morbidity (odds ratio [OR], 0.44; 95% confidence interval [CI], 0.30-0.65; p < 0.0001; I² = 0%); the effect size was greatest for FO-containing versus SO-based IVFEs. Relative to use of SO-based IVFEs, use of FO-containing IVFEs was associated with a significant reduction in hospital LOS (weighted mean difference, -2.70 days; 95% CI, -3.60 to -1.79 days; p < 0.00001; I² = 0%).

CONCLUSION

The results of the meta-analysis indicated that FO-containing IVFEs could improve infectious morbidity and LOS. The overall effect of reducing infectious morbidity and LOS was found to be the greatest in comparison with the SO-based IVFEs.

Intravenous Lipid Emulsions to Deliver Bioactive Omega-3 Fatty Acids for Improved Patient Outcomes

Lipids used in intravenous nutrition support (i.e., parenteral nutrition) provide energy, building blocks, and essential fatty acids. These lipids are included as emulsions since they need to be soluble in an aqueous environment. Fish oil is a source of bioactive omega-3 fatty acids (eicosapentaenoic acid and docosahexaenoic acid). Lipid emulsions, including fish oil, have been used for parenteral nutrition for adult patients post-surgery (mainly gastrointestinal). This has been associated with alterations in biomarkers of inflammation and immune defense, and in some studies, a reduction in length of intensive care unit and hospital stay. These benefits, along with a reduction in infections, are emphasized through recent meta-analyses. Perioperative administration of fish oil may be superior to postoperative administration, but this requires further exploration. Parenteral fish oil has been used in critically ill adult patients. Here, the influence on inflammatory processes, immune function, and clinical endpoints is less clear. However, some studies found reduced inflammation, improved gas exchange, and shorter length of hospital stay in critically ill patients if they received fish oil. Meta-analyses do not present a consistent picture but are limited by the small number and size of studies. More and better trials are needed in patient groups in which parenteral nutrition is used and where fish oil, as a source of bioactive omega-3 fatty acids, may offer benefits.

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

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

Intravenous n-3 fatty acids in the critically ill

PURPOSE OF REVIEW

Lipid emulsions are an integral part of parenteral nutrition. Enteral nutrition is the preferred route to feed critically ill patients and parenteral nutrition is used in case of contraindications or when enteral nutrition does not reach the nutritional goals. n-3 Lipids are included into some newer lipid emulsions including fish oil or may be added by a fish oil-based lipid emulsion to lipid emulsion without fish oil. This review focuses on recent clinical trials, metaanalyses, and guidelines of parenteral nutrition with n-3 lipids in critically ill patients.

RECENT FINDINGS

Two single-center studies report a mortality benefit of adding fish oil-based lipid emulsions to the parenteral nutrition. Metaanalyses performed without these two studies had demonstrated beneficial effects of n-3 lipids regarding infections, length of stay, and time of mechanical ventilation but not on mortality. However, all metaanalyses judged the database derived from the underlying studies as not sufficient for a firm recommendation. Consecutively, guidelines and expert groups issue very cautious recommendations for the use of n-3 lipids in parenteral nutrition.

SUMMARY

Beneficial effects of n-3 lipids in trials and metaanalyses became available; however, high-quality multicenter randomized controlled trials are needed before more endorsing recommendation will be available.

Efficacy of a long-term home parenteral nutrition regimen containing fish oil-derived n-3 polyunsaturated fatty acids: a single-centre, randomized, double blind study

Background

Data on the use of lipid emulsions containing fish-oil (FO) derived n-3 polyunsaturated fatty acids (n-3 PUFAs) in addition to medium- and long-chain triglycerides (MCT/LCT) for long-term home parenteral nutrition (HPN) are limited. This study aimed to compare HPN regimens containing either MCT/LCT/FO-derived n-3 PUFAs (test group) or MCT/LCT (control group) with respect to efficacy and safety during 8 weeks of HPN using a non-inferiority trial design with change of body mass index (BMI) as primary endpoint.

Methods

This prospective, randomized, double-blind study was conducted at the Charité, Berlin, Germany, from 02/2008 until 01/2014. Adult patients (n = 42; aged 18 to 80 years) requiring HPN for at least 8 weeks were randomly assigned to the test or control group. Assessments included weight, height, physical examination (cardiovascular system, abdomen, respiratory tract, liver, spleen, kidney, urine tract, skin, mucous membrane, neurology, psyche, musculoskeletal system, lymph nodes), bio impedance analysis, calorimetry, blood samplings (haematology, biochemistry, fatty acid analysis) and quality of life questionnaire.

Results

BMI increased in both groups with 8 weeks of HPN (ΔBMI_{(test group)} = 1.3 ± 1.1 kg/m²; ΔBMI_{(control group)} = 0.6 ± 0.9 kg/m²) demonstrating non-inferiority of the test regimen regarding nutritional efficacy. Assessment of secondary efficacy endpoints revealed that after 8 weeks of HPN with the test regimen, the proportion of n-3 PUFAs in serum, platelet and red blood cell phospholipids significantly increased, while the proportion of n-6 PUFAs decreased. The fatty acid pattern in the control group remained mostly stable. No statistically significant differences were detected between groups regarding inflammatory markers or quality of life. Laboratory parameters reflecting the safety endpoints liver function, bone metabolism, renal function, metabolic activity, lipid metabolism, coagulation and haematology were stable in both groups and no group differences were detected regarding (serious) adverse events.

Conclusions

The HPN regimen prepared with MCT/LCT/FO-derived n-3 PUFAs was at least as efficient in maintaining or even improving nutritional status during HPN as the control MCT/LCT regimen. Administration of FO-derived n-3 PUFAs for 8 weeks altered the fatty acid pattern of serum, platelet and red blood cell phospholipids. Both regimens were safe and well tolerated.

Trial registration

www.clinicaltrials.gov, registration number: NCT00530738.

Electronic supplementary material

The online version of this article (10.1186/s12937-018-0419-x) contains supplementary material, which is available to authorized users.

ESPEN guideline on clinical nutrition in the intensive care unit

Following the new ESPEN Standard Operating Procedures, the previous guidelines to provide best medical nutritional therapy to critically ill patients have been updated. These guidelines define who are the patients at risk, how to assess nutritional status of an ICU patient, how to define the amount of energy to provide, the route to choose and how to adapt according to various clinical conditions. When to start and how to progress in the administration of adequate provision of nutrients is also described. The best determination of amount and nature of carbohydrates, fat and protein are suggested. Special attention is given to glutamine and omega-3 fatty acids. Particular conditions frequently observed in intensive care such as patients with dysphagia, frail patients, multiple trauma patients, abdominal surgery, sepsis, and obesity are discussed to guide the practitioner toward the best evidence based therapy. Monitoring of this nutritional therapy is discussed in a separate document.

Intravenous lipid emulsions in the critically ill: an update

PURPOSE OF REVIEW

Purpose of the review is to summarize recent research addressing the role of intravenous lipid emulsions (IVLEs) in the critically ill.

RECENT FINDINGS

Soybean oil-based IVLEs, which are high in the omega-6 polyunsaturated fatty acids, have been largely used in parenteral nutrition over the last several decades. However, it is now generally accepted that the higher content of phytosterols and polyunsaturated fatty acids in soybean oil IVLE may adversely affect the immunological and inflammatory status of the critically ill. In the last few years, alternative IVLEs with lower soybean oil content have been associated with important improvements in clinical outcomes, such as mortality, mechanical ventilation days, and ICU length of stay. Olive oil and fish oil IVLEs have been reported to reduce the incidence of infections, with no clear benefits in other clinical outcomes. Despite the promising results with these new parenteral nutrition strategies, the optimum composition, dosage and indication for alternative IVLEs still remain controversial. Nevertheless, according to current knowledge alternative IVLEs may be associated with improved clinical outcomes and should be considered in critically ill patients requiring parenteral nutrition.

SUMMARY

There is a growing body of evidence suggesting that improved clinical outcomes can be achieved with selective use of alternative IVLEs in parenteral nutrition regimens for the critically ill. More high quality trials are needed, to better evaluate the efficacy of alternative IVLEs.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Composite Intravenous Fat Emulsion in a Postsurgical Critically Ill Patient: A Case Report

Parenteral nutrition (PN), including lipids, in high-risk or poorly nourished critically ill patients is indicated when enteral nutrition is contraindicated; however, soybean oil-based PN can stimulate proinflammatory processes. Fish oil (FO) is generally less inflammatory and has recently been shown to be active in the resolution of inflammatory processes. In this study, we look at whether the use of a blended intravenous fat emulsion that includes soybean, medium-chain triglycerides, olive oil, and FO confers clinical benefits in critically ill patients.

Resolution of inflammation and sepsis survival are improved by dietary Ω-3 fatty acids

Critical conditions such as sepsis following infection or traumatic injury disturb the complex state of homeostasis that may lead to uncontrolled inflammation resulting in organ failure, shock and death. They are associated with endogenous mediators that control the onset of acute inflammatory response, but the central problem remains the complete resolution of inflammation. Omega-3 enriched lipid emulsions (Ω-3⁺ LEs) were used in experimental studies and clinical trials to establish homeostasis, yet with little understanding about their role on the resolution of inflammation and tissue regeneration. Here, we demonstrate that Ω-3 lipid emulsions (LEs) orchestrate inflammation-resolution/regeneration mechanism during sterile peritonitis and murine polymicrobial sepsis. Ω-3⁺ LEs recessed neutrophil infiltration, reduced pro-inflammatory mediators, reduced the classical monocyte and enhanced the non-classical monocytes/macrophages recruitment and finally increased the efferocytosis in sepsis. The actions of Ω-3⁺ LE were 5-lipoxygenase (5-LOX) and 12/15-lipoxygenase (12/15-LOX) dependent. Ω-3⁺ LEs shortened the resolution interval by 56%, stimulated the endogenous biosynthesis of resolution mediators lipoxin A4, protectin DX and maresin 1 and contributed to tissue regeneration. Ω-3⁺ LEs protected against hypothermia and weight loss and enhanced survival in murine polymicrobial sepsis. We highlighted a role of Ω-3⁺ LEs in regulating key mechanisms within the resolution terrain during murine sepsis. This might form the basis for a rational design of sepsis specific clinical nutrition.

Lipids in the intensive care unit: Recommendations from the ESPEN Expert Group

This article summarizes the presentations given at an ESPEN Workshop on "Lipids in the ICU" held in Tel Aviv, Israel in November 2014 and subsequent discussions and updates. Lipids are an important component of enteral and parenteral nutrition support and provide essential fatty acids, a concentrated source of calories and building blocks for cell membranes. Whilst linoleic acid-rich vegetable oil-based enteral and parenteral nutrition is still widely used, newer lipid components such as medium-chain triglycerides and olive oil are safe and well tolerated. Fish oil (FO)-enriched enteral and parenteral nutrition appears to be well tolerated and confers additional clinical benefits, particularly in surgical patients, due to its anti-inflammatory and immune-modulating effects. Whilst the evidence base is not conclusive, there appears to be a potential for FO-enriched nutrition, particularly administered peri-operatively, to reduce the rate of complications and intensive care unit (ICU) and hospital stay in surgical ICU patients. The evidence for FO-enriched nutrition in non-surgical ICU patients is less clear regarding its clinical benefits and additional, well-designed large-scale clinical trials need to be conducted in this area. The ESPEN Expert Group supports the use of olive oil and FO in nutrition support in surgical and non-surgical ICU patients but considers that further research is required to provide a more robust evidence base.

Parenteral nutrition including an omega-3 fatty-acid-containing lipid emulsion for intensive care patients in China: a pharmacoeconomic analysis

Background/objectives

Parenteral nutrition (PN) incorporating omega-3 fatty-acid-enriched lipid emulsions has been shown to be cost effective in Western populations. A pharmacoeconomic evaluation was performed within the Chinese intensive care unit (ICU) setting. This assessed whether the additional acquisition cost of PN with omega-3 fatty-acid-enriched lipid emulsion (SMOFlipid) vs standard PN was offset by improved clinical outcomes that can reduce subsequent costs.

Materials and methods

A pharmacoeconomic discrete event simulation model was developed, based on an update to efficacy data from a previous international meta-analysis, with China-specific clinical and economic input parameters. Sensitivity analyses were undertaken to assess the effects of uncertainty around input parameters.

Results

The model predicted that PN with an omega-3 fatty-acid-enriched lipid emulsion was more effective and less costly than PN with standard lipid emulsions for Chinese ICU patients, as follows: reduced length of overall hospital length of stay (19.48 vs 21.35 days, respectively), reduced length of ICU stay (5.03 vs 6.18 days, respectively), and prevention of 35.6% of nosocomial infections leading to a lower total cost per patient (¥47 189 [US $6937] vs ¥54 783 [US $8053], respectively). Additional treatment costs were offset by savings in overall hospital and ICU stay cost, and antibiotic cost, resulting in a mean cost saving of ¥7594 (US $1116) per patient. Sensitivity analyses confirmed the robustness of these findings.

Conclusions

PN enriched with an omega-3 fatty-acid-containing lipid emulsion vs standard PN may be effective in reducing length of hospital and ICU stay and infectious complications in Chinese ICU patients, and also decreases overall treatment costs. This results in a favorable cost-effectiveness ratio. Thus, PN enriched with an omega-3 fatty-acid-containing lipid emulsion can be seen as a win–win situation for patients, hospital administration, and health insurance companies.

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.

Omega-3 supplementation in patients with sepsis: a systematic review and meta-analysis of randomized trials

BACKGROUND

Nutritional supplementation of omega-3 fatty acids has been proposed to modulate the balance of pro- and anti-inflammatory mediators in sepsis. If proved to improve clinical outcomes in critically ill patients with sepsis, this intervention would be easy to implement. However, the cumulative evidence from several randomized clinical trials (RCTs) remains unclear.

METHODS

We searched the Cochrane Library, MEDLINE, and EMBASE through December 2016 for RCTs on parenteral or enteral omega-3 supplementation in adult critically ill patients diagnosed with sepsis or septic shock. We analysed the included studies for mortality, intensive care unit (ICU) length of stay, and duration of mechanical ventilation, and used the Grading of Recommendations Assessment, Development and Evaluation approach to assess the quality of the evidence for each outcome.

RESULTS

A total of 17 RCTs enrolling 1239 patients met our inclusion criteria. Omega-3 supplementation compared to no supplementation or placebo had no significant effect on mortality [relative risk (RR) 0.85; 95% confidence interval (CI) 0.71, 1.03; P = 0.10; I ² = 0%; moderate quality], but significantly reduced ICU length of stay [mean difference (MD) -3.79 days; 95% CI -5.49, -2.09; P < 0.0001, I ² = 82%; very low quality] and duration of mechanical ventilation (MD -2.27 days; 95% CI -4.27, -0.27; P = 0.03, I ² = 60%; very low quality). However, sensitivity analyses challenged the robustness of these results.

CONCLUSION

Omega-3 nutritional supplementation may reduce ICU length of stay and duration of mechanical ventilation without significantly affecting mortality, but the very low quality of overall evidence is insufficient to justify the routine use of omega-3 fatty acids in the management of sepsis.

Preoperative carbohydrate load and intraoperatively infused omega-3 polyunsaturated fatty acids positively impact nosocomial morbidity after coronary artery bypass grafting: a double-blind controlled randomized trial

Background

A strategy of limited preoperative fasting, with carbohydrate (CHO) loading and intraoperative infusion of omega-3 polyunsaturated fatty acids (ω-3 PUFA), has seldom been tried in cardiovascular surgery. Brief fasting, followed by CHO intake 2 h before anesthesia, may improve recovery from CABG procedures and lower perioperative vasoactive drug requirements. Infusion of ω-3 PUFA may reduce occurrences of postoperative atrial fibrillation (POAF) and shorten hospital stays. The aim of this study was to assess morbidity (especially POAF) in ICU patients after coronary artery bypass grafting (CABG)/cardiopulmonary bypass (CPB) in combination, if preoperative fasts are curtailed in favor of CHO loading, and ω-3 PUFA are infused intraoperatively.

Methods

Fifty-seven patients undergoing CABG were randomly assigned to receive 12.5% maltodextrin (200 ml, 2 h before anesthesia), without infusing ω-3 PUFA (CHO, n = 14); water (200 ml, 2 h before anesthesia), without infusing ω-3 PUFA (controls, n = 14); 12.5% maltodextrin (200 ml, 2 h before anesthesia) plus intraoperative ω-3 PUFA (0.2 mcg/kg) (CHO + W3, n = 15); or water (200 ml, 2 h before anesthesia) plus intraoperative ω-3 PUFA (0.2 mcg/kg) (W3, n = 14). Perioperative clinical variables and mortality were analyzed, examining the incidence of POAF, as well as the need for inotropic vasoactive drugs during surgery and in ICU.

Results

Two deaths occurred (3.5%), but there were no instances of bronchoaspiration and mediastinitis. Neither ICU stays nor total postoperative stays differed by group (P > 0.05). Patients given preoperative CHO loads (CHO and CHO + W3 groups) experienced fewer instances of hospital infection (RR = 0.29, 95%CI 0.09–0.94; P = 0.023) and were less reliant on vasoactive amines during surgery (RR = 0.60, 95% CI 0.38–0.94; P = 0.020). Similarly, the number of patients requiring vasoactive drugs while recovering in ICU differed significantly by group (P = 0.008), showing benefits in patients given CHO loads. The overall incidence of POAF was 29.8% (17/57), differing significantly by group (P = 0.009). Groups given ω-3 PUFA (W3 and CHO + W3 groups) experienced significantly fewer instances of POAF (RR = 4.83, 95% CI 1.56–15.02; P = 0.001).

Conclusion

Preoperative curtailment of fasting was safe in this cohort. When implemented in conjunction with CHO loading and infusion of ω-3 PUFA during surgery, expedited recovery from CABG with CPB was observed.

Trial registration

NCT: 03017001

Parenteral Nutrition and Lipids

Lipids have multiple physiological roles that are biologically vital. Soybean oil lipid emulsions have been the mainstay of parenteral nutrition lipid formulations for decades in North America. Utilizing intravenous lipid emulsions in parenteral nutrition has minimized the dependence on dextrose as a major source of nonprotein calories and prevents the clinical consequences of essential fatty acid deficiency. Emerging literature has indicated that there are benefits to utilizing alternative lipids such as olive/soy-based formulations, and combination lipids such as soy/MCT/olive/fish oil, compared with soybean based lipids, as they have less inflammatory properties, are immune modulating, have higher antioxidant content, decrease risk of cholestasis, and improve clinical outcomes in certain subgroups of patients. The objective of this article is to review the history of IVLE, their composition, the different generations of widely available IVLE, the variables to consider when selecting lipids, and the complications of IVLE and how to minimize them.

Pro-Resolving Molecules-New Approaches to Treat Sepsis?

Inflammation is a complex response of the body to exogenous and endogenous insults. Chronic and systemic diseases are attributed to uncontrolled inflammation. Molecules involved in the initiation of inflammation are very well studied while pathways regulating its resolution are insufficiently investigated. Approaches to down-modulate mediators relevant for the onset and duration of inflammation are successful in some chronic diseases, while all of them have failed in sepsis patients. Inflammation and immune suppression characterize sepsis, indicating that anti-inflammatory strategies alone are inappropriate for its therapy. Heme oxygenase 1 is a sensitive marker for oxidative stress and is upregulated in inflammation. Carbon monoxide, which is produced by this enzyme, initiates multiple anti-inflammatory and pro-resolving activities with higher production of omega-3 fatty acid-derived lipid metabolites being one of its protective actions. Pro-resolving lipids named maresins, resolvins and protectins originate from the omega-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid while lipoxins are derived from arachidonic acid. These endogenously produced lipids do not simply limit inflammation but actively contribute to its resolution, and thus provide an opportunity to combat chronic inflammatory diseases and eventually sepsis.

The impact of an omega-3 fatty acid rich lipid emulsion on fatty acid profiles in critically ill septic patients

BACKGROUND

Death from sepsis in the intensive therapy unit (ITU) is frequently preceded by the development of multiple organ failure as a result of uncontrolled inflammation. Treatment with omega-3 (n-3) fatty acids (FAs), principally eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), has been demonstrated to attenuate the effects of uncontrolled inflammation and may be clinically beneficial in reducing mortality from organ dysfunction. Fish oil (FO) is a source of EPA and DHA.

METHODS

A randomized trial investigating the effects of parenteral (intravenous) nutrition providing FO (0.092g EPA+DHA/kg body weight/day) was conducted. Sixty consecutive ITU patients diagnosed with sepsis were randomised to receive either once daily parenteral FO and standard medical care or standard medical care only.

RESULTS

Forty one patients (21 received fish oil; 20 controls) consented to blood sampling and blood was taken on days 0, 1, 2, 3, 5, 7, 10 and 13; because of deaths, patient discharge and withdrawal of consent, the number of blood samples available for analysis diminished with time. FA composition of plasma phosphatidylcholine (PC), plasma non-esterified FAs (NEFAs) and peripheral blood mononuclear cells (PBMCs) was determined by gas chromatography. EPA and DHA were rapidly incorporated into all 3 lipid pools investigated. There was a reduction in the arachidonic acid (AA) to EPA+DHA ratio in plasma PC and NEFAs. Fewer patients died in the FO group (13.3% (n=4)) compared with the control group (26.7% (n=8)) but this difference was not significant. A reduction in the AA/(EPA+DHA) ratio in PBMCs and plasma PC was associated with significantly improved survival. Plasma PC, plasma NEFA and PBMC FA profiles are rapidly altered by FO infusion in critically ill septic patients.

CONCLUSION

The provision of high dose n-3 FAs resulted in a rapid and significant increase in EPA and DHA and a reduction in AA/(EPA+DHA) ratio. This latter reduction is associated with improved survival.

Parenteral Nutrition and Infection Risk in the Intensive Care Unit: A Practical Guide for the Bedside Clinician

The safety of parenteral nutrition (PN) administration in critically ill patients has been the subject of much controversy. Historically, PN administration has been associated with an increased risk of bacterial and fungal infections, leading to significant morbidity and mortality. Much of the data showing increased infectious complications compared with either no nutrition or enteral nutrition was derived from early studies conducted in the 1980s-2000s. Poor glucose control and hyperalimentation are confounding factors in many early studies, making it difficult to determine the true PN infection risks. While PN studies conducted during the past 10 years have failed to show the same infection rates, these risks continue to be cited as dogma. Potential reasons for such discordant results include improved glycemic control, avoidance of overfeeding, and improved sterility and central venous catheter care. Understanding the true infectious risk of PN administration in the intensive care unit is necessary to optimize patient care, as inappropriately withholding such nutrition is potentially deleterious. This review is meant to serve as a practical guide to the bedside clinician who is evaluating the risks and benefits of initiating PN in a critically ill patient. Each component of PN will be evaluated based on risk of infection, and the potential ways to mitigate risks will be discussed.

Fishmeal supplementation during ovine pregnancy and lactation protects against maternal stress-induced programming of the offspring immune system

BACKGROUND

Prenatally stressed offspring exhibit increased susceptibility to inflammatory disorders due to in utero programming. Research into the effects of n-3 PUFAs shows promising results for the treatment and prevention of these disorders. The purpose of this study was to investigate whether maternal fishmeal supplementation during pregnancy and lactation protects against programming of the offspring's immune response following simulated maternal infection.

METHODS

In order to accomplish this, 53 ewes were fed a diet supplemented with fishmeal (FM; rich in n-3 PUFA) or soybean meal (SM; rich in n-6 PUFAs) from day 100 of gestation (gd 100) through lactation. On gd135, half the ewes from each dietary group were challenged with either 1.2 μg/kg Escherichia coli lipopolysaccharide (LPS) endotoxin to simulate a bacterial infection, or saline as the control. At 4.5 months of age the offspring's dermal immune response was assessed by cutaneous hypersensitivity testing with ovalbumin (OVA) and candida albicans (CAA) 21 days after sensitization. Skinfold measurements were taken and serum blood samples were also collected to assess the primary and secondary antibody immune response.

RESULTS

Offspring born to SM + LPS mothers had a significantly greater change in skinfold thickness in response to both antigens as well as a greater secondary antibody response to OVA compared to all treatments.

CONCLUSIONS

Supplementation during pregnancy with FM appears to protect against adverse fetal programming that may occur during maternal infection and this may reduce the risk of atopic disease later in life.

[Fish oil containing lipid emulsions in critically ill patients: Critical analysis and future perspectives]

Third-generation lipid emulsions (LE) are soybean oil sparing strategies with immunomodulatory and antiinflammatory effects. Current evidence supporting the use of intravenous (i.v) fish oil (FO) LE in critically ill patients requiring parenteral nutrition or receiving enteral nutrition (pharmaconutrient strategy) mainly derives from small phase ii clinical trials in heterogenous intensive care unit patient's population. Over the last three years, there have been published different systematic reviews and meta-analyses evaluating the effects of FO containing LE in the critically ill. Recently, it has been demonstrated that i.v FO based LE may be able to significantly reduce the incidence of infections as well as mechanical ventilation days and hospital length of stay. Nonetheless, more robust evidence is required before giving a definitive recommendation. Finally, we strongly believe that a dosing study is required before new phase iii clinical trials comparing i.v FO containing emulsions versus other soybean oil strategies can be conducted.