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de Man AME, Gunst J, Reintam Blaser A. Nutrition in the intensive care unit: from the acute phase to beyond. Intensive Care Med 2024; 50:1035-1048. [PMID: 38771368 PMCID: PMC11245425 DOI: 10.1007/s00134-024-07458-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 04/21/2024] [Indexed: 05/22/2024]
Abstract
Recent randomized controlled trials (RCTs) have shown no benefit but dose-dependent harm by early full nutritional support in critically ill patients. Lack of benefit may be explained by anabolic resistance, suppression of cellular repair processes, and aggravation of hyperglycemia and insulin needs. Also early high amino acid doses did not provide benefit, but instead associated with harm in patients with organ dysfunctions. However, most studies focused on nutritional interventions initiated during the first days after intensive care unit admission. Although the intervention window of some RCTs extended into the post-acute phase of critical illness, no large RCTs studied nutritional interventions initiated beyond the first week. Hence, clear evidence-based guidance on when and how to initiate and advance nutrition is lacking. Prolonged underfeeding will come at a price as there is no validated metabolic monitor that indicates readiness for medical nutrition therapy, and an adequate response to nutrition, which likely varies between patients. Also micronutrient status cannot be assessed reliably, as inflammation can cause redistribution, so that plasma micronutrient concentrations are not necessarily reflective of total body stores. Moreover, high doses of individual micronutrients have not proven beneficial. Accordingly, current evidence provides clear guidance on which nutritional strategies to avoid, but the ideal nutritional regimen for individual patients remains unclear. In this narrative review, we summarize the findings of recent studies, discuss possible mechanisms explaining the results, point out pitfalls in interpretation of RCTs and their effect on clinical practice, and formulate suggestions for future research.
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Affiliation(s)
- Angelique M E de Man
- Department of Intensive Care, Amsterdam UMC, Location Vrije Universiteit, Amsterdam, The Netherlands.
- Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands.
| | - Jan Gunst
- Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
- Department of Intensive Care Medicine, University Hospitals Leuven, Leuven, Belgium
| | - Annika Reintam Blaser
- Department of Anaesthesiology and Intensive Care, University of Tartu, Tartu, Estonia
- Department of Intensive Care Medicine, Lucerne Cantonal Hospital, Spitalstrasse, 6000, Lucerne, Switzerland
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Van den Berghe G, Vanhorebeek I, Langouche L, Gunst J. Our Scientific Journey through the Ups and Downs of Blood Glucose Control in the ICU. Am J Respir Crit Care Med 2024; 209:497-506. [PMID: 37991900 DOI: 10.1164/rccm.202309-1696so] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 11/22/2023] [Indexed: 11/24/2023] Open
Abstract
This article tells the story of our long search for the answer to one question: Is stress hyperglycemia in critically ill patients adaptive or maladaptive? Our earlier work had suggested the lack of hepatic insulin effect and hyperglycemia as jointly predicting poor outcome. Therefore, we hypothesized that insulin infusion to reach normoglycemia, tight glucose control, improves outcome. In three randomized controlled trials (RCTs), we found morbidity and mortality benefit with tight glucose control. Moving from the bed to the bench, we attributed benefits to the prevention of glucose toxicity in cells taking up glucose in an insulin-independent, glucose concentration gradient-dependent manner, counteracted rather than synergized by insulin. Several subsequent RCTs did not confirm benefit, and the large Normoglycemia in Intensive Care Evaluation-Survival Using Glucose Algorithm Regulation, or "NICE-SUGAR," trial found increased mortality with tight glucose control associated with severe hypoglycemia. Our subsequent clinical and mechanistic research revealed that early use of parenteral nutrition, the context of our initial RCTs, had been a confounder. Early parenteral nutrition (early-PN) aggravated hyperglycemia, suppressed vital cell damage removal, and hampered recovery. Therefore, in our next and largest "TGC-fast" RCT, we retested our hypothesis, without the use of early-PN and with a computer algorithm for tight glucose control that avoided severe hypoglycemia. In this trial, tight glucose control prevented kidney and liver damage, though with much smaller effect sizes than in our initial RCTs without affecting mortality. Our quest ends with the strong recommendation to omit early-PN for patients in the ICU, as this reduces need of blood glucose control and allows cellular housekeeping systems to play evolutionary selected roles in the recovery process. Once again, less is more in critical care.
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Affiliation(s)
- Greet Van den Berghe
- Clinical Division of Intensive Care Medicine, UZ Leuven, Leuven, Belgium; and
- Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Ilse Vanhorebeek
- Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Lies Langouche
- Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Jan Gunst
- Clinical Division of Intensive Care Medicine, UZ Leuven, Leuven, Belgium; and
- Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
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Chadda KR, Puthucheary Z. Persistent inflammation, immunosuppression, and catabolism syndrome (PICS): a review of definitions, potential therapies, and research priorities. Br J Anaesth 2024; 132:507-518. [PMID: 38177003 PMCID: PMC10870139 DOI: 10.1016/j.bja.2023.11.052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 11/17/2023] [Accepted: 11/19/2023] [Indexed: 01/06/2024] Open
Abstract
Persistent Inflammation, Immunosuppression, and Catabolism Syndrome (PICS) is a clinical endotype of chronic critical illness. PICS consists of a self-perpetuating cycle of ongoing organ dysfunction, inflammation, and catabolism resulting in sarcopenia, immunosuppression leading to recurrent infections, metabolic derangements, and changes in bone marrow function. There is heterogeneity regarding the definition of PICS. Currently, there are no licensed treatments specifically for PICS. However, findings can be extrapolated from studies in other conditions with similar features to repurpose drugs, and in animal models. Drugs that can restore immune homeostasis by stimulating lymphocyte production could have potential efficacy. Another treatment could be modifying myeloid-derived suppressor cell (MDSC) activation after day 14 when they are immunosuppressive. Drugs such as interleukin (IL)-1 and IL-6 receptor antagonists might reduce persistent inflammation, although they need to be given at specific time points to avoid adverse effects. Antioxidants could treat the oxidative stress caused by mitochondrial dysfunction in PICS. Possible anti-catabolic agents include testosterone, oxandrolone, IGF-1 (insulin-like growth factor-1), bortezomib, and MURF1 (muscle RING-finger protein-1) inhibitors. Nutritional support strategies that could slow PICS progression include ketogenic feeding and probiotics. The field would benefit from a consensus definition of PICS using biologically based cut-off values. Future research should focus on expanding knowledge on underlying pathophysiological mechanisms of PICS to identify and validate other potential endotypes of chronic critical illness and subsequent treatable traits. There is unlikely to be a universal treatment for PICS, and a multimodal, timely, and personalised therapeutic strategy will be needed to improve outcomes for this growing cohort of patients.
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Affiliation(s)
- Karan R Chadda
- William Harvey Research Institute, Barts and The London School of Medicine & Dentistry, Queen Mary University of London, London, UK; Homerton College, University of Cambridge, Cambridge, UK; Birmingham Acute Care Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK.
| | - Zudin Puthucheary
- William Harvey Research Institute, Barts and The London School of Medicine & Dentistry, Queen Mary University of London, London, UK; Adult Critical Care Unit, Royal London Hospital, London, UK
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Callahan JC, Parot-Schinkel E, Asfar P, Ehrmann S, Tirot P, Guitton C. Impact of daily cyclic enteral nutrition versus standard continuous enteral nutrition in critically ill patients: a study protocol for a randomised controlled trial in three intensive care units in France (DC-SCENIC). BMJ Open 2024; 14:e080003. [PMID: 38286683 PMCID: PMC10826523 DOI: 10.1136/bmjopen-2023-080003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 12/19/2023] [Indexed: 01/31/2024] Open
Abstract
INTRODUCTION Current guidelines on clinical nutrition of ventilated patients in the intensive care unit (ICU) recommend initiating continuous enteral nutrition within 48 hours of ICU admission when feasible. However, discontinuous feeding regimens, alternating feeding and fasting intervals, may have an impact on clinical and patient centred outcomes. The ongoing "Impact of daily cyclic enteral nutrition versus standard continuous enteral nutrition in critically ill patients" (DC-SCENIC) trial aims to compare standard continuous enteral feeding with daily cyclic enteral feeding over 10 hours to evaluate if implementing a fasting-mimicking diet can decrease organ failure in ventilated patients during the acute phase of ICU management. METHODS AND ANALYSIS DC-SCENIC is a randomised, controlled, multicentre, open-label trial comparing two parallel groups of patients 18 years of age or older receiving invasive mechanical ventilation and having an indication for enteral nutrition through a gastric tube. Enteral feeding is continuous in the control group and administered over 10 hours daily in the intervention group. Both groups receive isocaloric nutrition with 4 g of protein per 100 mL, and have the same 20 kcal/kg/day caloric target. The primary endpoint is the change in the Sequential Organ Failure Assessment score at 7 days compared with the day of inclusion in the study. Secondary outcomes include daily caloric and protein delivery, digestive, respiratory and metabolic tolerance as well as 28-day mortality, duration of mechanical ventilation and ventilator-free days. Outcomes will be analysed on an intention-to-treat basis. Recruitment started in June 2023 in 3 French ICU's and a sample size of 318 patients is expected by February 2026. ETHICS AND DISSEMINATION This study received approval from the national ethics review board on 8 November 2022 (Comité de Protection des Personnes Sud-Est VI, registration number 2022-A00827-36). Patients are included after informed consent. Results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER NCT05627167.
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Affiliation(s)
| | - Elsa Parot-Schinkel
- Biostatistics and Methodology Department, Centre Hospitalier Universitaire d'Angers, Angers, France
| | - Pierre Asfar
- Service de Médecine Intensive Réanimation, Centre Hospitalier Universitaire d'Angers, Angers, France
| | - Stephan Ehrmann
- Service de Médecine Intensive Réanimation, Centre Hospitalier Régional Universitaire de Tours, Tours, France
| | - Patrice Tirot
- Service de Réanimation Polyvalente, Centre Hospitalier du Mans, Le Mans, France
| | - Christophe Guitton
- Service de Réanimation Polyvalente, Centre Hospitalier du Mans, Le Mans, France
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Veldscholte K, Hulst JM, Eveleens RD, de Jonge RC, de Koning BA, van den Berg SA, van der Wal R, Ruijter GJ, Rizopoulos D, Vanhorebeek I, Gunst J, Casaer M, Van den Berghe G, Joosten KF, Verbruggen SC. Gastrointestinal Biomarkers and Their Association with Feeding in the First Five Days of Pediatric Critical Illness. J Pediatr Gastroenterol Nutr 2023; 77:811-818. [PMID: 37728917 PMCID: PMC10642702 DOI: 10.1097/mpg.0000000000003950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 09/01/2023] [Indexed: 09/22/2023]
Abstract
OBJECTIVES Predicting the patients' tolerance to enteral nutrition (EN) would help clinicians optimize individual nutritional intake. This study investigated the course of several gastrointestinal (GI) biomarkers and their association with EN advancement (ENA) longitudinally during pediatric intensive care unit (PICU) admission. METHODS This is a secondary analysis of the Early versus Late Parenteral Nutrition in the Pediatric Intensive Care Unit randomized controlled trial. EN was started early and increased gradually. The cholecystokinin (CCK), leptin, glucagon, intestinal fatty acid-binding protein 2 (I-FABP2), and citrulline plasma concentrations were measured upon PICU admission, day 3 and day 5. ENA was defined as kcal EN provided as % of predicted resting energy expenditure. The course of the biomarkers and ENA was examined in patients with samples on all time points using Friedman and Wilcoxon signed-rank tests. The association of ENA with the biomarkers was examined using a 2-part mixed-effects model with data of the complete population, adjusted for possible confounders. RESULTS For 172 patients, median age 8.6 years (first quartile; third quartile: 4.2; 13.4), samples were available, of which 55 had samples on all time points. The median ENA was 0 (0; 0) on admission, 14.5 (0.0; 43.8) on day 3, and 28.0 (7.6; 94.8) on day 5. During PICU stay, CCK and I-FABP2 concentrations decreased significantly, whereas glucagon concentrations increased significantly, and leptin and citrulline remained stable. None of the biomarkers was longitudinally associated with ENA. CONCLUSIONS Based on the current evidence, CCK, leptin, glucagon, I-FABP2, and citrulline appear to have no added value in predicting ENA in the first 5 days of pediatric critical illness.
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Affiliation(s)
- Karlien Veldscholte
- From the Department of Neonatal and Pediatric Intensive Care, Division of Pediatric Intensive Care, Erasmus MC Sophia Children’s Hospital, Rotterdam, The Netherlands
| | - Jessie M. Hulst
- the Department of Pediatrics, University of Toronto, Toronto, Canada
- the Department of Nutritional Sciences, University of Toronto, Toronto, Canada
- the Division of Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children, Toronto, Canada
| | - Renate D. Eveleens
- the Department of Anesthesiology, Amsterdam University Medical Centers, AMC, Amsterdam, the Netherlands
| | - Rogier C.J. de Jonge
- From the Department of Neonatal and Pediatric Intensive Care, Division of Pediatric Intensive Care, Erasmus MC Sophia Children’s Hospital, Rotterdam, The Netherlands
| | - Barbara A.E. de Koning
- Pediatric Gastroenterology, Erasmus MC Sophia Children’s Hospital, Rotterdam, the Netherlands
| | - Sjoerd A.A. van den Berg
- the Department of Clinical Chemistry, Erasmus MC, Rotterdam, The Netherlands
- the Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Ronald van der Wal
- the Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands
| | | | - Dimitris Rizopoulos
- the Department of Biostatistics, Erasmus MC, Rotterdam, the Netherlands
- the Department of Epidemiology, Erasmus MC, Rotterdam, the Netherlands
| | - Ilse Vanhorebeek
- the Department of Anesthesiology, Amsterdam University Medical Centers, AMC, Amsterdam, the Netherlands
| | - Jan Gunst
- the Department of Anesthesiology, Amsterdam University Medical Centers, AMC, Amsterdam, the Netherlands
| | - Michaël Casaer
- the Department of Anesthesiology, Amsterdam University Medical Centers, AMC, Amsterdam, the Netherlands
| | - Greet Van den Berghe
- the Department of Anesthesiology, Amsterdam University Medical Centers, AMC, Amsterdam, the Netherlands
| | - Koen F.M. Joosten
- From the Department of Neonatal and Pediatric Intensive Care, Division of Pediatric Intensive Care, Erasmus MC Sophia Children’s Hospital, Rotterdam, The Netherlands
| | - Sascha C.A.T. Verbruggen
- From the Department of Neonatal and Pediatric Intensive Care, Division of Pediatric Intensive Care, Erasmus MC Sophia Children’s Hospital, Rotterdam, The Netherlands
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Lauwers C, De Bruyn L, Langouche L. Impact of critical illness on cholesterol and fatty acids: insights into pathophysiology and therapeutic targets. Intensive Care Med Exp 2023; 11:84. [PMID: 38015312 PMCID: PMC10684846 DOI: 10.1186/s40635-023-00570-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 11/21/2023] [Indexed: 11/29/2023] Open
Abstract
Critical illness is characterized by a hypercatabolic response encompassing endocrine and metabolic alterations. Not only the uptake, synthesis and metabolism of glucose and amino acids is majorly affected, but also the homeostasis of lipids and cholesterol is altered during acute and prolonged critical illness. Patients who suffer from critically ill conditions such as sepsis, major trauma, surgery or burn wounds display an immediate and sustained reduction in low plasma LDL-, HDL- and total cholesterol concentrations, together with a, less pronounced, increase in plasma free fatty acids. The severity of these alterations is associated with severity of illness, but the underlying pathophysiological mechanisms are multifactorial and only partly clarified. This narrative review aims to provide an overview of the current knowledge of how lipid and cholesterol uptake, synthesis and metabolism is affected during critical illness. Reduced nutritional uptake, increased scavenging of lipoproteins as well as an increased conversion to cortisol or other cholesterol-derived metabolites might all play a role in the decrease in plasma cholesterol. The acute stress response to critical illness creates a lipolytic cocktail, which might explain the increase in plasma free fatty acids, although reduced uptake and oxidation, but also increased lipogenesis, especially in prolonged critical illness, will also affect the circulating levels. Whether a disturbed lipid homeostasis warrants intervention or should primarily be interpreted as a signal of severity of illness requires further research.
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Affiliation(s)
- Caroline Lauwers
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, O&N1 Box 503, 3000, Leuven, Belgium
| | - Lauren De Bruyn
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, O&N1 Box 503, 3000, Leuven, Belgium
| | - Lies Langouche
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, O&N1 Box 503, 3000, Leuven, Belgium.
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Wilkinson D, Gallagher IJ, McNelly A, Bear DE, Hart N, Montgomery HE, Le Guennec A, Conte MR, Francis T, Harridge SDR, Atherton PJ, Puthucheary ZA. The metabolic effects of intermittent versus continuous feeding in critically ill patients. Sci Rep 2023; 13:19508. [PMID: 37945671 PMCID: PMC10636009 DOI: 10.1038/s41598-023-46490-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Accepted: 11/01/2023] [Indexed: 11/12/2023] Open
Abstract
Intermittent (or bolus) feeding regimens in critically ill patients have been of increasing interest to clinicians and scientists. Changes in amino acid, fat and carbohydrate metabolites over time might yet deliver other benefits (e.g. modulation of the circadian rhythm and sleep, and impacts on ghrelin secretion, insulin resistance and autophagy). We set out to characterise these changes in metabolite concentration. The Intermittent versus Continuous Feeding in Critically Ill paitents study (NCT02358512) was an eight-centre single-blinded randomised controlled trial. Patients were randomised to received a continuous (control arm) or intermittent (6x/day, intervention arm) enteral feeding regimen. Blood samples were taken on trial days 1, 7 and 10 immediately before and 30 min after intermittent feeds, and at equivalent timepoints in the control arm. A pre-planned targeted metabolomic analysis was performend using Nuclear Resonance Spectroscopy. Five hundred and ninety four samples were analysed from 75 patients. A total of 24 amino acid-, 19 lipid based-, and 44 small molecule metabolite features. Across the main two axes of variation (40-60% and 6-8% of variance), no broad patterns distinguished between intermittent or continuous feeding arms, across intra-day sampling times or over the 10 days from initial ICU admission. Logfold decreases in abundance were seen in metabolites related to amino acids (Glutamine - 0.682; Alanine - 0.594), ketone body metabolism (Acetone - 0.64; 3-Hydroxybutyric Acid - 0.632; Acetonacetic Acid - 0.586), fatty acid (carnitine - 0.509) and carbohydrate metabolism ( Maltose - 0.510; Citric Acid - 0.485). 2-3 Butanediol, a by-product of sugar-fermenting microbial metabolism also decreased (- 0.489). No correlation was seen with change in quadriceps muscle mass for any of the 20 metabolites varying with time (all p > 0.05). Increasing severity of organ failure was related to increasing ketone body metabolism (3 Hydroxybutyric Acid-1 and - 3; p = 0.056 and p = 0.014), carnitine deficiency (p = 0.002) and alanine abundancy (p - 0.005). A 6-times a day intermittent feeding regimen did not alter metabolite patterns across time compared to continuous feeding in critically ill patients, either within a 24 h period or across 10 days of intervention. Future research on intermittent feeding regimens should focus on clinical process benefits, or extended gut rest and fasting.
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Affiliation(s)
- D Wilkinson
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, Metabolic and Molecular Physiology, University of Nottingham, Queen's Medical Cetnre, Nottingham, UK
- National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottinghan University Hospitals and University of Nottingham, Queen's Medical Centre, Nottingham, UK
- School of Medicine, University of Nottingham, Royal Derby Hospital, Derby, UK
| | | | - A McNelly
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - D E Bear
- Department of Nutrition and Dietetics St Thomas' NHS Foundation Trust, London, UK
- Department of Critical Care, Guy's and St. Thomas' NHS Foundation & King's College London (KCL) NIHR BRC, London, UK
- Centre for Human and Applied Physiological Science, King's College London, London, UK
| | - N Hart
- Lane Fox Respiratory Service, Guy's & St Thomas' Foundation Trust, London, UK
- Lane Fox Clinical Respiratory Physiology Research Centre, Kings College London, London, UK
| | - H E Montgomery
- Department of Medicine and Centre for Human Health and Performance, University College London (UCL), London, UK
| | - A Le Guennec
- Centre for Biomolecular Spectroscopy, Guy's Campus, King's College London, London, UK
- Randall Centre for Cell and Molecular Biophysics, Guy's Campus, King's College London, London, UK
| | - M R Conte
- Centre for Biomolecular Spectroscopy, Guy's Campus, King's College London, London, UK
- Randall Centre for Cell and Molecular Biophysics, Guy's Campus, King's College London, London, UK
| | - T Francis
- Centre for Human and Applied Physiological Science, King's College London, London, UK
| | - S D R Harridge
- Centre for Human and Applied Physiological Science, King's College London, London, UK
| | - P J Atherton
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, Metabolic and Molecular Physiology, University of Nottingham, Queen's Medical Cetnre, Nottingham, UK
- National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottinghan University Hospitals and University of Nottingham, Queen's Medical Centre, Nottingham, UK
- School of Medicine, University of Nottingham, Royal Derby Hospital, Derby, UK
| | - Z A Puthucheary
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
- Randall Centre for Cell and Molecular Biophysics, Guy's Campus, King's College London, London, UK.
- Adult Critical Care Unit, Royal London Hospital, Whitechapel, London, E1 1BB, UK.
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Veldscholte K, Cramer ABG, de Jonge RCJ, Rizopoulos D, Joosten KFM, Verbruggen SCAT. Intermittent feeding with an overnight fast versus 24-h feeding in critically ill neonates, infants, and children: An open-label, single-centre, randomised controlled trial. Clin Nutr 2023; 42:1569-1580. [PMID: 37478810 DOI: 10.1016/j.clnu.2023.07.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 07/10/2023] [Accepted: 07/10/2023] [Indexed: 07/23/2023]
Abstract
BACKGROUND & AIMS Critically ill children are fed day and night, assuming this improves enteral tolerance and the probability of achieving nutritional goals. It was previously shown that a fasting response, reflected by increased ketosis, at least partly explained the beneficial outcome of delayed initiation of supplemental parenteral nutrition. This study aims to investigate whether an overnight fast increases ketosis and is feasible and safe in critically ill children. METHODS The Continuousversus Intermittent Nutrition in Paediatric Intensive Care (ContInNuPIC) study is a randomised controlled trial in a tertiary referral Paediatric Intensive Care Unit (PICU) in the Netherlands. Critically ill children (term newborn-18 years) with an expected PICU stay ≥48 h, dependent on artificial nutrition, were eligible. Participants were randomly assigned (1:1, stratified for age group) to intermittent feeding, with interruption of feedings during an age-dependent overnight period of eight to 12 h, or to continuous feeding, with the administration of feedings day and night. In both groups, similar daily caloric targets were pursued. For children younger than one year, mandatory minor glucose infusions were provided during fasting. The primary outcome was the feasibility, defined as two conditions (1): a significant difference in the patients' highest daily ketone (3-β-hydroxybutyrate, BHB) levels during each overnight period, and (2): non-inferiority regarding daily caloric intake, examined using a two-part mixed-effects model with a predefined non-inferiority margin of 33%, in an intention-to-treat analysis. The study is registered in the Netherlands Trial Register (NL7877). RESULTS Between May 19, 2020, and July 13, 2022, 140 critically ill children, median (first quartile; third quartile) age 0.3 (0.1; 2.7) years, were randomised to intermittent (n = 67) or continuous feeding (n = 73). In the intermittent feeding group, BHB levels were significantly higher (median 0.4 (0.2; 1.0) vs. 0.3 (0.1; 0.7) mmol/L, p < 0.001). The ratio of total caloric intake in the intermittent feeding group to the intake in the continuous feeding group was not consistently significantly more than 0.67, thus not proving non-inferiority. No severe, resistant hypoglycaemic events, nor severe gastrointestinal complications related to the intervention occurred, and feeding intolerance did not occur more often in the intermittent than in the continuous feeding group. CONCLUSION Compared with day and night feeding, intermittent feeding with an overnight fast and mandatory glucose infusion for children younger than one year marginally increased ketosis and did not lead to more hypoglycaemic incidents in critically ill children. Because non-inferiority regarding daily caloric intake was not proven, the feasibility of an overnight fast could not be shown in the current study. However, as feeding intolerance did not increase during the condensed feeding periods, the nutritional intake was probably limited by the prescription of nutrition and interruptions. More research is needed to determine the optimal level and duration of clinically relevant ketosis and the best method to achieve this.
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Affiliation(s)
- Karlien Veldscholte
- Department of Neonatal and Paediatric Intensive Care, Division of Paediatric Intensive Care, Erasmus MC Sophia Children's Hospital, Rotterdam, the Netherlands
| | - Arnout B G Cramer
- Department of Neonatal and Paediatric Intensive Care, Division of Paediatric Intensive Care, Erasmus MC Sophia Children's Hospital, Rotterdam, the Netherlands
| | - Rogier C J de Jonge
- Department of Neonatal and Paediatric Intensive Care, Division of Paediatric Intensive Care, Erasmus MC Sophia Children's Hospital, Rotterdam, the Netherlands
| | - Dimitris Rizopoulos
- Department of Biostatistics, Erasmus MC, Rotterdam, the Netherlands; Department of Epidemiology, Erasmus MC, Rotterdam, the Netherlands
| | - Koen F M Joosten
- Department of Neonatal and Paediatric Intensive Care, Division of Paediatric Intensive Care, Erasmus MC Sophia Children's Hospital, Rotterdam, the Netherlands
| | - Sascha C A T Verbruggen
- Department of Neonatal and Paediatric Intensive Care, Division of Paediatric Intensive Care, Erasmus MC Sophia Children's Hospital, Rotterdam, the Netherlands.
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Wischmeyer PE, Bear DE, Berger MM, De Waele E, Gunst J, McClave SA, Prado CM, Puthucheary Z, Ridley EJ, Van den Berghe G, van Zanten ARH. Personalized nutrition therapy in critical care: 10 expert recommendations. Crit Care 2023; 27:261. [PMID: 37403125 DOI: 10.1186/s13054-023-04539-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 06/22/2023] [Indexed: 07/06/2023] Open
Abstract
Personalization of ICU nutrition is essential to future of critical care. Recommendations from American/European guidelines and practice suggestions incorporating recent literature are presented. Low-dose enteral nutrition (EN) or parenteral nutrition (PN) can be started within 48 h of admission. While EN is preferred route of delivery, new data highlight PN can be given safely without increased risk; thus, when early EN is not feasible, provision of isocaloric PN is effective and results in similar outcomes. Indirect calorimetry (IC) measurement of energy expenditure (EE) is recommended by both European/American guidelines after stabilization post-ICU admission. Below-measured EE (~ 70%) targets should be used during early phase and increased to match EE later in stay. Low-dose protein delivery can be used early (~ D1-2) (< 0.8 g/kg/d) and progressed to ≥ 1.2 g/kg/d as patients stabilize, with consideration of avoiding higher protein in unstable patients and in acute kidney injury not on CRRT. Intermittent-feeding schedules hold promise for further research. Clinicians must be aware of delivered energy/protein and what percentage of targets delivered nutrition represents. Computerized nutrition monitoring systems/platforms have become widely available. In patients at risk of micronutrient/vitamin losses (i.e., CRRT), evaluation of micronutrient levels should be considered post-ICU days 5-7 with repletion of deficiencies where indicated. In future, we hope use of muscle monitors such as ultrasound, CT scan, and/or BIA will be utilized to assess nutrition risk and monitor response to nutrition. Use of specialized anabolic nutrients such as HMB, creatine, and leucine to improve strength/muscle mass is promising in other populations and deserves future study. In post-ICU setting, continued use of IC measurement and other muscle measures should be considered to guide nutrition. Research on using rehabilitation interventions such as cardiopulmonary exercise testing (CPET) to guide post-ICU exercise/rehabilitation prescription and using anabolic agents such as testosterone/oxandrolone to promote post-ICU recovery is needed.
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Affiliation(s)
- Paul E Wischmeyer
- Department of Anesthesiology and Surgery, Duke University School of Medicine, Box 3094 Mail # 41, 2301 Erwin Road, 5692 HAFS, Durham, NC, USA.
| | - Danielle E Bear
- Departments of Nutrition and Dietetics and Critical Care, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Mette M Berger
- Faculty of Biology & Medicine, Lausanne University, Lausanne, Switzerland
| | - Elisabeth De Waele
- Department of Clinical Nutrition, Universitair Ziekenhuis Brussel, Brussels, Belgium
- Vrije Universiteit Brussel, Brussels, Belgium
| | - Jan Gunst
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Louvain, Belgium
| | - Stephen A McClave
- Department of Medicine, University of Louisville School of Medicine, Louisville, KY, USA
| | - Carla M Prado
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Zudin Puthucheary
- William Harvey Research Institute, Queen Mary University of London, London, UK
- Royal London Hospital, Barts Health NHS Trust, London, UK
| | - Emma J Ridley
- Australian and New Zealand Intensive Care Research Centre, School of Public Health and Preventive Medicine, Monash University, Level 3, 553 St Kilda Rd, Melbourne, VIC, 3004, Australia
- Dietetics and Nutrition, Alfred Hospital, 55 Commercial Rd, Melbourne, VIC, 3004, Australia
| | - Greet Van den Berghe
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Louvain, Belgium
| | - Arthur R H van Zanten
- Department of Intensive Care, Gelderse Vallei Hospital, Wageningen University & Research, Ede, The Netherlands
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10
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Reintam Blaser A, Rooyackers O, Bear DE. How to avoid harm with feeding critically ill patients: a synthesis of viewpoints of a basic scientist, dietitian and intensivist. Crit Care 2023; 27:258. [PMID: 37393289 PMCID: PMC10314407 DOI: 10.1186/s13054-023-04543-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 06/22/2023] [Indexed: 07/03/2023] Open
Abstract
The optimal feeding strategy in critically ill patients is a matter of debate, with current guidelines recommending different strategies regarding energy and protein targets. Several recent trials have added to the debate and question our previous understanding of the provision of nutrition during critical illness. This narrative review aims to provide a summary of interpretation of recent evidence from the view of basic scientist, critical care dietitian and intensivist, resulting in joined suggestions for both clinical practice and future research. In the most recent randomised controlled trial (RCT), patients receiving 6 versus 25 kcal/kg/day by any route achieved readiness for ICU discharge earlier and had fewer GI complications. A second showed that high protein dosage may be harmful in patients with baseline acute kidney injury and more severe illness. Lastly, a prospective observational study using propensity score matched analysis suggested that early full feeding, especially enteral, compared to delayed feeding is associated with a higher 28-day mortality. Viewpoints from all three professionals point to the agreement that early full feeding is likely harmful, whereas important questions regarding the mechanisms of harm as well as on timing and optimal dose of nutrition for individual patients remain unanswered and warrant future studies. For now, we suggest giving low dose of energy and protein during the first few days in the ICU and apply individualised approach based on assumed metabolic state according to the trajectory of illness thereafter. At the same time, we encourage research to develop better tools to monitor metabolism and the nutritional needs for the individual patient accurately and continuously.
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Affiliation(s)
- Annika Reintam Blaser
- Department of Anaesthesiology and Intensive Care, University of Tartu, Puusepa 8, 50406, Tartu, Estonia.
- Department of Intensive Care Medicine, Lucerne Cantonal Hospital, Lucerne, Switzerland.
| | - Olav Rooyackers
- Division of Anesthesiology and Intensive Care, Department of Clinical Science, Technology and Intervention, Karolinska Institutet, Huddinge, Sweden
| | - Danielle E Bear
- Department of Nutrition and Dietetics, Guy's and St Thomas' NHS Foundation Trust, London, UK
- Department of Critical Care, Guy's and St Thomas' NHS Foundation Trust, London, UK
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11
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Gunst J, De Bruyn A, Jacobs A, Langouche L, Derese I, Dulfer K, Güiza F, Garcia Guerra G, Wouters PJ, Joosten KF, Verbruggen SC, Vanhorebeek I, Van den Berghe G. The association of hypoglycemia with outcome of critically ill children in relation to nutritional and blood glucose control strategies. Crit Care 2023; 27:251. [PMID: 37365667 DOI: 10.1186/s13054-023-04514-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 05/31/2023] [Indexed: 06/28/2023] Open
Abstract
BACKGROUND Withholding parenteral nutrition (PN) until one week after PICU admission facilitated recovery from critical illness and protected against emotional and behavioral problems 4 years later. However, the intervention increased the risk of hypoglycemia, which may have counteracted part of the benefit. Previously, hypoglycemia occurring under tight glucose control in critically ill children receiving early PN did not associate with long-term harm. We investigated whether hypoglycemia in PICU differentially associates with outcome in the context of withholding early PN, and whether any potential association with outcome may depend on the applied glucose control protocol. METHODS In this secondary analysis of the multicenter PEPaNIC RCT, we studied whether hypoglycemia in PICU associated with mortality (N = 1440) and 4-years neurodevelopmental outcome (N = 674) through univariable comparison and multivariable regression analyses adjusting for potential confounders. In patients with available blood samples (N = 556), multivariable models were additionally adjusted for baseline serum NSE and S100B concentrations as biomarkers of neuronal, respectively, astrocytic damage. To study whether an association of hypoglycemia with outcome may be affected by the nutritional strategy or center-specific glucose control protocol, we further adjusted the models for the interaction between hypoglycemia and the randomized nutritional strategy, respectively, treatment center. In sensitivity analyses, we studied whether any association with outcome was different in patients with iatrogenic or spontaneous/recurrent hypoglycemia. RESULTS Hypoglycemia univariably associated with higher mortality in PICU, at 90 days and 4 years after randomization, but not when adjusted for risk factors. After 4 years, critically ill children with hypoglycemia scored significantly worse for certain parent/caregiver-reported executive functions (working memory, planning and organization, metacognition) than patients without hypoglycemia, also when adjusted for risk factors including baseline NSE and S100B. Further adjustment for the interaction of hypoglycemia with the randomized intervention or treatment center revealed a potential interaction, whereby tight glucose control and withholding early PN may be protective. Impaired executive functions were most pronounced in patients with spontaneous or recurrent hypoglycemia. CONCLUSION Critically ill children exposed to hypoglycemia in PICU were at higher risk of impaired executive functions after 4 years, especially in cases of spontaneous/recurrent hypoglycemia.
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Affiliation(s)
- Jan Gunst
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, B-3000, Leuven, Belgium.
| | - Astrid De Bruyn
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, B-3000, Leuven, Belgium
| | - An Jacobs
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, B-3000, Leuven, Belgium
| | - Lies Langouche
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, B-3000, Leuven, Belgium
| | - Inge Derese
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, B-3000, Leuven, Belgium
| | - Karolijn Dulfer
- Intensive Care Unit, Department of Pediatrics and Pediatric Surgery, Erasmus Medical Center, Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Fabian Güiza
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, B-3000, Leuven, Belgium
| | - Gonzalo Garcia Guerra
- Intensive Care Unit, Department of Pediatrics, University of Alberta, Stollery Children's Hospital, Edmonton, Canada
- Pediatric Intensive Care Unit, Department of Pediatrics, University of Calgary, Alberta Children's Hospital, Calgary, Canada
| | - Pieter J Wouters
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, B-3000, Leuven, Belgium
| | - Koen F Joosten
- Intensive Care Unit, Department of Pediatrics and Pediatric Surgery, Erasmus Medical Center, Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Sascha C Verbruggen
- Intensive Care Unit, Department of Pediatrics and Pediatric Surgery, Erasmus Medical Center, Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Ilse Vanhorebeek
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, B-3000, Leuven, Belgium
| | - Greet Van den Berghe
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, B-3000, Leuven, Belgium
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12
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Gunst J, Casaer MP, Preiser JC, Reignier J, Van den Berghe G. Toward nutrition improving outcome of critically ill patients: How to interpret recent feeding RCTs? Crit Care 2023; 27:43. [PMID: 36707883 PMCID: PMC9883882 DOI: 10.1186/s13054-023-04317-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 01/11/2023] [Indexed: 01/29/2023] Open
Abstract
Although numerous observational studies associated underfeeding with poor outcome, recent randomized controlled trials (RCTs) have shown that early full nutritional support does not benefit critically ill patients and may induce dose-dependent harm. Some researchers have suggested that the absence of benefit in RCTs may be attributed to overrepresentation of patients deemed at low nutritional risk, or to a too low amino acid versus non-protein energy dose in the nutritional formula. However, these hypotheses have not been confirmed by strong evidence. RCTs have not revealed any subgroup benefiting from early full nutritional support, nor benefit from increased amino acid doses or from indirect calorimetry-based energy dosing targeted at 100% of energy expenditure. Mechanistic studies attributed the absence of benefit of early feeding to anabolic resistance and futile catabolism of extra provided amino acids, and to feeding-induced suppression of recovery-enhancing pathways such as autophagy and ketogenesis, which opened perspectives for fasting-mimicking diets and ketone supplementation. Yet, the presence or absence of an anabolic response to feeding cannot be predicted or monitored and likely differs over time and among patients. In the absence of such monitor, the value of indirect calorimetry seems obscure, especially in the acute phase of illness. Until now, large feeding RCTs have focused on interventions that were initiated in the first week of critical illness. There are no large RCTs that investigated the impact of different feeding strategies initiated after the acute phase and continued after discharge from the intensive care unit in patients recovering from critical illness.
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Affiliation(s)
- Jan Gunst
- grid.5596.f0000 0001 0668 7884Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Michael P. Casaer
- grid.5596.f0000 0001 0668 7884Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Jean-Charles Preiser
- grid.4989.c0000 0001 2348 0746Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Jean Reignier
- grid.4817.a0000 0001 2189 0784Service de Médecine Intensive Réanimation, Centre Hospitalier Universitaire de Nantes, Université de Nantes, Nantes, France
| | - Greet Van den Berghe
- grid.5596.f0000 0001 0668 7884Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
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13
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Soni S, Martens MD, Takahara S, Silver HL, Maayah ZH, Ussher JR, Ferdaoussi M, Dyck JRB. Exogenous ketone ester administration attenuates systemic inflammation and reduces organ damage in a lipopolysaccharide model of sepsis. Biochim Biophys Acta Mol Basis Dis 2022; 1868:166507. [PMID: 35902007 DOI: 10.1016/j.bbadis.2022.166507] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/19/2022] [Accepted: 07/21/2022] [Indexed: 12/20/2022]
Abstract
AIMS Sepsis is a life-threatening condition of organ dysfunction caused by dysregulated inflammation which predisposes patients to developing cardiovascular disease. The ketone β-hydroxybutyrate is reported to be cardioprotective in cardiovascular disease and this may be due to their signaling properties that contribute to reducing inflammation. While exogenous ketone esters (KE) increase blood ketone levels, it remains unknown whether KEs can reduce the enhanced inflammatory response and multi-organ dysfunction that is observed in sepsis. Thus, this study assesses whether a recently developed and clinically safe KE can effectively improve the inflammatory response and organ dysfunction in sepsis. METHODS AND RESULTS To assess the anti-inflammatory effects of a KE, we utilized a model of lipopolysaccharide (LPS)-induced sepsis in which an enhanced inflammatory response results in multi-organ dysfunction. Oral administration of KE for three days prior to LPS-injection significantly protected mice against the profound systemic inflammation compared to their vehicle-treated counterparts. In assessing organ dysfunction, KE protected mice from sepsis-induced cardiac dysfunction as well as renal dysfunction and fibrosis. Furthermore, KE administration attenuated the sepsis-induced inflammation in the heart, kidney, and liver. Moreover, these protective effects occurred independent of changes to enzymes involved in ketone metabolism. CONCLUSION These data show that the use of an exogenous KE attenuates the dysregulated systemic and organ inflammation as well as organ dysfunction in a model of severe inflammation. We postulate that this exogenous KE is an appealing and promising approach to capitalize on the protective anti-inflammatory effects of ketones in sepsis and/or other inflammatory responses.
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Affiliation(s)
- Shubham Soni
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada; Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Matthew D Martens
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada; Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Shingo Takahara
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada; Division of Cardiovascular Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Heidi L Silver
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada; Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Zaid H Maayah
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada; Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - John R Ussher
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada; Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Mourad Ferdaoussi
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada; Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Jason R B Dyck
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada; Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.
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14
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Nadamuni M, Venable AH, Huen SC. When a calorie isn't just a calorie: a revised look at nutrition in critically ill patients with sepsis and acute kidney injury. Curr Opin Nephrol Hypertens 2022; 31:358-366. [PMID: 35703214 PMCID: PMC9248034 DOI: 10.1097/mnh.0000000000000801] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW To discuss how nutritional management could be optimized to promote protective metabolism in sepsis and associated acute kidney injury. RECENT FINDINGS Recent evidence suggests that sepsis is a metabolically distinct critical illness and that certain metabolic alterations, such as activation of fasting metabolism, may be protective in bacterial sepsis. These findings may explain the lack of survival benefit in recent randomized controlled trials of nutrition therapy for critical illness. These trials are limited by cohort heterogeneity, combining both septic and nonseptic critical illness, and the use of inaccurate caloric estimates to determine energy requirements. These energy estimates are also unable to provide information on specific substrate preferences or the capacity for substrate utilization. As a result, high protein feeding beyond the capacity for protein synthesis could cause harm in septic patients. Excess glucose and insulin exposures suppress fatty acid oxidation, ketogenesis and autophagy, of which emerging evidence suggest are protective against sepsis associated organ damage such as acute kidney injury. SUMMARY Distinguishing pathogenic and protective sepsis-related metabolic changes are critical to enhancing and individualizing nutrition management for critically ill patients.
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Affiliation(s)
| | | | - Sarah C Huen
- Department of Internal Medicine
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, USA
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15
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Weckx R, Goossens C, Derde S, Pauwels L, Vander Perre S, Van den Berghe G, Langouche L. Efficacy and safety of ketone ester infusion to prevent muscle weakness in a mouse model of sepsis-induced critical illness. Sci Rep 2022; 12:10591. [PMID: 35732826 PMCID: PMC9217969 DOI: 10.1038/s41598-022-14961-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 06/15/2022] [Indexed: 02/03/2023] Open
Abstract
In septic mice, 3-hydroxybutyrate-sodium-salt has shown to partially prevent sepsis-induced muscle weakness. Although effective, the excessive sodium load was toxic. We here investigated whether ketone ester 3-hydroxybutyl-3-hydroxybutanoate (3HHB) was a safer alternative. In a mouse model of abdominal sepsis, the effects of increasing bolus doses of 3HHB enantiomers on mortality, morbidity and muscle force were investigated (n = 376). Next, plasma 3HB- clearance after bolus d-3HHB was investigated (n = 27). Subsequently, in septic mice, the effect on mortality and muscle force of a continuous d,l-3HHB infusion was investigated (n = 72). In septic mice, as compared with placebo, muscle force was increased at 20 mmol/kg/day l-3HHB and at 40 mmol/kg/day d- and d,l-3HHB. However, severity of illness and mortality was increased by doubling the effective bolus doses. Bolus 3HHB caused a higher 3HB− plasma peak and slower clearance with sepsis. Unlike bolus injections, continuous infusion of d,l-3HHB did not increase severity of illness or mortality, while remaining effective in improving muscle force. Treatment of septic mice with the ketone ester 3HHB partly prevented muscle weakness. Toxicity of 3HHB administered as bolus was completely avoided by continuous infusion of the same dose. Whether continuous infusion of ketone esters represents a promising intervention to also prevent ICU-acquired weakness in human patients should be investigated.
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Affiliation(s)
- Ruben Weckx
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, O&N1 bus 503, 3000, Leuven, Belgium
| | - Chloë Goossens
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, O&N1 bus 503, 3000, Leuven, Belgium
| | - Sarah Derde
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, O&N1 bus 503, 3000, Leuven, Belgium
| | - Lies Pauwels
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, O&N1 bus 503, 3000, Leuven, Belgium
| | - Sarah Vander Perre
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, O&N1 bus 503, 3000, Leuven, Belgium
| | - Greet Van den Berghe
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, O&N1 bus 503, 3000, Leuven, Belgium
| | - Lies Langouche
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, O&N1 bus 503, 3000, Leuven, Belgium.
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16
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Novel insights in endocrine and metabolic pathways in sepsis and gaps for future research. Clin Sci (Lond) 2022; 136:861-878. [PMID: 35642779 DOI: 10.1042/cs20211003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/17/2022] [Accepted: 05/19/2022] [Indexed: 11/17/2022]
Abstract
Sepsis is defined as any life-threatening organ dysfunction caused by a dysregulated host response to infection. It remains an important cause of critical illness and has considerable short- and long-term morbidity and mortality. In the last decades, preclinical and clinical research has revealed a biphasic pattern in the (neuro-)endocrine responses to sepsis as to other forms of critical illness, contributing to development of severe metabolic alterations. Immediately after the critical illness-inducing insult, fasting- and stress-induced neuroendocrine and cellular responses evoke a catabolic state in order to provide energy substrates for vital tissues, and to concomitantly activate cellular repair pathways while energy-consuming anabolism is postponed. Large randomized controlled trials have shown that providing early full feeding in this acute phase induced harm and reversed some of the neuro-endocrine alterations, which suggested that the acute fasting- and stress-induced responses to critical illness are likely interlinked and benefical. However, it remains unclear whether, in the context of accepting virtual fasting in the acute phase of illness, metabolic alterations such as hyperglycemia are harmful or beneficial. When patients enter a prolonged phase of critical illness, a central suppression of most neuroendocrine axes follows. Prolonged fasting and central neuroendocrine suppression may no longer be beneficial. Although pilot studies have suggested benefit of fasting-mimicking diets and interventions that reactivate the central neuroendocrine suppression selectively in the prolonged phase of illness, further study is needed to investigate patient-oriented outcomes in larger randomized trials.
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17
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Veldscholte K, Cramer ABG, de Jonge RCJ, Eveleens RD, Joosten KFM, Verbruggen SCAT. Continuous versus Intermittent Nutrition in Pediatric Intensive Care patients (ContInNuPIC): a study protocol for a randomized controlled trial (Preprint). JMIR Res Protoc 2022; 11:e36229. [PMID: 35737448 PMCID: PMC9264130 DOI: 10.2196/36229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 05/17/2022] [Accepted: 05/17/2022] [Indexed: 11/13/2022] Open
Abstract
Background Objective Methods Results Conclusions Trial Registration International Registered Report Identifier (IRRID)
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Affiliation(s)
- Karlien Veldscholte
- Intensive Care Unit, Department of Pediatrics and Pediatric Surgery, Erasmus MC - Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Arnout B G Cramer
- Intensive Care Unit, Department of Pediatrics and Pediatric Surgery, Erasmus MC - Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Rogier C J de Jonge
- Intensive Care Unit, Department of Pediatrics and Pediatric Surgery, Erasmus MC - Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Renate D Eveleens
- Department of Anesthesiology, Location Amsterdam Medical Center, Amsterdam University Medical Centers, Amsterdam, Netherlands
| | - Koenraad F M Joosten
- Intensive Care Unit, Department of Pediatrics and Pediatric Surgery, Erasmus MC - Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Sascha C A T Verbruggen
- Intensive Care Unit, Department of Pediatrics and Pediatric Surgery, Erasmus MC - Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, Netherlands
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18
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Impact of tight glucose control on circulating 3-hydroxybutyrate in critically ill patients. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2021; 25:373. [PMID: 34696774 PMCID: PMC8547101 DOI: 10.1186/s13054-021-03772-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 09/14/2021] [Indexed: 12/13/2022]
Abstract
BACKGROUND Recent evidence suggests a potentially protective effect of increasing ketone body availability via accepting low macronutrient intake early after onset of critical illness. The impact of blood glucose control with insulin on circulating ketones is unclear. Whereas lowering blood glucose may activate ketogenesis, high insulin concentrations may have the opposite effect. We hypothesized that the previously reported protective effects of tight glucose control in critically ill patients receiving early parenteral nutrition may have been mediated in part by activation of ketogenesis. METHODS This is a secondary analysis of 3 randomized controlled trials on tight versus liberal blood glucose control in the intensive care unit, including 700 critically ill children and 2748 critically ill adults. All patients received early parenteral nutrition as part of the contemporary standard of care. Before studying a potential mediator role of circulating ketones in improving outcome, we performed a time course analysis to investigate whether tight glucose control significantly affected ketogenesis and to identify a day of maximal effect, if any. We quantified plasma/serum 3-hydroxybutyrate concentrations from intensive care unit admission until day 3 in 2 matched subsets of 100 critically ill children and 100 critically ill adults. Univariable differences between groups were investigated by Kruskal-Wallis test. Differences in 3-hydroxybutyrate concentrations between study days were investigated by Wilcoxon signed-rank test. RESULTS In critically ill children and adults receiving early parenteral nutrition, tight glucose control, as compared with liberal glucose control, lowered mean morning blood glucose on days 1-3 (P < 0.0001) via infusing insulin at a higher dose (P < 0.0001). Throughout the study period, caloric intake was not different between groups. In both children and adults, tight glucose control did not affect 3-hydroxybutyrate concentrations, which were suppressed on ICU days 1-3 and significantly lower than the ICU admission values for both groups (P < 0.0001). CONCLUSION Tight versus liberal glucose control in the context of early parenteral nutrition did not affect 3-hydroxybutyrate concentrations in critically ill patients. Hence, the protective effects of tight glucose control in this context cannot be attributed to increased ketone body availability.
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19
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Veldscholte K, Cramer ABG, Joosten KFM, Verbruggen SCAT. Intermittent fasting in paediatric critical illness: The properties and potential beneficial effects of an overnight fast in the PICU. Clin Nutr 2021; 40:5122-5132. [PMID: 34461586 DOI: 10.1016/j.clnu.2021.07.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/21/2021] [Accepted: 07/26/2021] [Indexed: 12/30/2022]
Abstract
Although evidence for the superiority of continuous feeding over intermittent feeding is lacking, in most paediatric intensive care units (PICU) artificial feeding is administered continuously for 24 h per day. Until now, studies in PICU on intermittent feeding have primarily focused on surrogate endpoints such as nutritional intake and gastro-intestinal complaints and none have studied the effects of an extended fasting period. Intermittent fasting has been proven to have many health benefits in both animal and human studies. The observed beneficial effects are based on multiple metabolic and endocrine changes that are presumed crucial in critical illness as well. One key element is the transition to ketone body metabolism, which, among others, contributes to the stimulation of several cellular pathways involved in stress resistance (neuro)plasticity and mitochondrial biogenesis, and might help preserve brain function. Secondly, the fasting state stimulates the activation of autophagy, a process that is crucial for cellular function and integrity. Of the different intermittent fasting strategies investigated, time-restricted feeding with a daily extended fasting period appears most feasible in the PICU. Moreover, planning the fasting period overnight could help maintain the circadian rhythm. Although not investigated, such an overnight intermittent fasting strategy might improve the metabolic profile, feeding tolerance and perhaps even have beneficial effects on tissue repair, reperfusion injury, muscle weakness, and the immune response. Future studies should investigate practical implications in critically ill children and the optimal duration of the fasting periods, which might be affected by the severity of illness and by age.
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Affiliation(s)
- Karlien Veldscholte
- Intensive Care Unit, Department of Paediatrics and Paediatric Surgery, Erasmus Medical Centre, Sophia Children's Hospital, Rotterdam, the Netherlands
| | - Arnout B G Cramer
- Intensive Care Unit, Department of Paediatrics and Paediatric Surgery, Erasmus Medical Centre, Sophia Children's Hospital, Rotterdam, the Netherlands
| | - Koen F M Joosten
- Intensive Care Unit, Department of Paediatrics and Paediatric Surgery, Erasmus Medical Centre, Sophia Children's Hospital, Rotterdam, the Netherlands
| | - Sascha C A T Verbruggen
- Intensive Care Unit, Department of Paediatrics and Paediatric Surgery, Erasmus Medical Centre, Sophia Children's Hospital, Rotterdam, the Netherlands.
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20
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Hofmaenner DA, Kleyman A, Singer M. Cholesterol and its association with muscle weakness in critical illness. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2021; 25:296. [PMID: 34404474 PMCID: PMC8371860 DOI: 10.1186/s13054-021-03722-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 07/29/2021] [Indexed: 11/10/2022]
Affiliation(s)
- Daniel A Hofmaenner
- Bloomsbury Institute of Intensive Care Medicine, Division of Medicine, University College London, London, WC1E 6BT, UK.
| | - Anna Kleyman
- Bloomsbury Institute of Intensive Care Medicine, Division of Medicine, University College London, London, WC1E 6BT, UK
| | - Mervyn Singer
- Bloomsbury Institute of Intensive Care Medicine, Division of Medicine, University College London, London, WC1E 6BT, UK
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21
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Moltu SJ, Bronsky J, Embleton N, Gerasimidis K, Indrio F, Köglmeier J, de Koning B, Lapillonne A, Norsa L, Verduci E, Domellöf M. Nutritional Management of the Critically Ill Neonate: A Position Paper of the ESPGHAN Committee on Nutrition. J Pediatr Gastroenterol Nutr 2021; 73:274-289. [PMID: 33605663 DOI: 10.1097/mpg.0000000000003076] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
OBJECTIVES The nutritional management of critically ill term neonates and preterm infants varies widely, and controversies exist in regard to when to initiate nutrition, mode of feeding, energy requirements, and composition of enteral and parenteral feeds. Recommendations for nutritional support in critical illness are needed. METHODS The ESPGHAN Committee on Nutrition (ESPGHAN-CoN) conducted a systematic literature search on nutritional support in critically ill neonates, including studies on basic metabolism. The Medline database and the Cochrane Library were used in the search for relevant publications. The quality of evidence was reviewed and discussed before voting on recommendations, and a consensus of 90% or more was required for the final approval. Important research gaps were also identified. RESULTS This position paper provides clinical recommendations on nutritional support during different phases of critical illness in preterm and term neonates based on available literature and expert opinion. CONCLUSION Basic research along with adequately powered trials are urgently needed to resolve key uncertainties on metabolism and nutrient requirements in this heterogeneous patient population.
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Affiliation(s)
| | - Jiri Bronsky
- Department of Paediatrics, University Hospital Motol, Prague, Czech Republic
| | - Nicholas Embleton
- Newcastle Neonatal Service, Newcastle Hospitals NHS Trust and Newcastle University, Newcastle upon Tyne, UK
| | - Konstantinos Gerasimidis
- Human Nutrition, School of Medicine, Dentistry and Nursing, University of Glasgow, New Lister Building, Glasgow Royal Infirmary, Glasgow, UK
| | - Flavia Indrio
- Department of Medical and Surgical Sciences, University of Foggia, Italy
| | - Jutta Köglmeier
- Department of paediatric Gastroenterology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Barbara de Koning
- Paediatric Gastroenterology, Erasmus MC-Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Alexandre Lapillonne
- Paris University, APHP Necker-Enfants Malades hospital, Paris, France and CNRC, Baylor College of Medicine, Houston, TX
| | - Lorenzo Norsa
- Paediatreic Hepatology Gastroenterology and Transplantation, ASST Papa Giovanni XXIIII, Bergamo, Italy
| | - Elvira Verduci
- Department of Health Sciences, University of Milan; Department of Paediatrics, Ospedale dei Bambini Vittore Buzzi Milan, Italy
| | - Magnus Domellöf
- Department of Clinical Sciences, Paediatrics, Umeå University, Umeå, Sweden
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22
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Abstract
PURPOSE OF REVIEW To summarize the clinical evidence for beneficial effects of ketones, ketogenic diets and intermittent fasting in critical illness, and to review potential mechanisms behind such effects. RECENT FINDINGS Recent evidence demonstrates that activation of a metabolic fasting response may be beneficial to recover from critical insults. Potential protective mechanisms are, among others, activation of ketogenesis and of damage removal by autophagy. Novel feeding strategies, including ketone supplements, ketogenic diets and intermittent fasting regimens, can activate these pathways - at least partially - in critically ill patients. Randomized controlled trials (RCTs) studying these novel feeding strategies as compared with standard care, are scarce and have not shown consistent benefit. Yet, all RCTs were small and underpowered for clinical endpoints. Moreover, in intermittent fasting studies, the duration of the fasting interval may have been too short to develop a sustained metabolic fasting response. SUMMARY These findings open perspectives for the further development of fasting-mimicking diets. Ultimately, clinical benefit should be confirmed by RCTs that are adequately powered for clinically relevant, patient-centered endpoints.
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Flower L, Page A, Puthucheary Z. Should nutritional therapy be modified to account for mitochondrial dysfunction in critical illness? JPEN J Parenter Enteral Nutr 2021; 45:60-65. [PMID: 34115880 DOI: 10.1002/jpen.2190] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/21/2021] [Accepted: 05/10/2021] [Indexed: 11/07/2022]
Abstract
Metabolic dysfunction, and its associated muscle atrophy, remains the most common complication of critical care. At the centre of this is mitochondrial dysfunction, secondary to hypoxia and systemic inflammation. This leads to a bioenergetic crisis, with decreased intramuscular adenosine tri-phosphate content and a reduction in the highly energy dependent process of protein synthesis. Numerous methods have been studied to try and reduce these effects, with only limited success. Trials investigating the use of increased calorie and protein administration have instead found a decrease in relative lean body mass, and a potential increase in morbidity and mortality. Ketone bodies have been proposed as alternative substrates for metabolism in critical illness, with promising results seen in animal models. They are currently being investigated in critical care patients in the Alternative Substrates in the Critically Ill Subjects trial. The evidence to date suggests that individualised feeding regimens may be key in the nutritional approach to critical illness. Consideration of individual patient factors will need to be combined with personalised protein content, total energy load received, and the timings of such feeds. This review covers mitochondrial dysfunction in critical illness, and how it contributes to muscle wasting and the resultant morbidity and mortality and the scientific basis of why current nutritional approaches to date have not been successful in negating this effect. These two factors underpin the need for consideration of alternative nutritional strategies in the critically ill patient. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Luke Flower
- William Harvey Research Institute, Queen Mary University of London, London.,Department of Anaesthesia, University College Hospital, 235 Euston Road, London, UK
| | - Alexandria Page
- William Harvey Research Institute, Queen Mary University of London, London.,Adult Critical Care Unit, The Royal London Hospital, Barts Health NHS Trust, Whitechapel Road, London, UK
| | - Zudin Puthucheary
- William Harvey Research Institute, Queen Mary University of London, London.,Adult Critical Care Unit, The Royal London Hospital, Barts Health NHS Trust, Whitechapel Road, London, UK
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De Bruyn A, Langouche L, Vander Perre S, Gunst J, Van den Berghe G. Impact of withholding early parenteral nutrition in adult critically ill patients on ketogenesis in relation to outcome. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2021; 25:102. [PMID: 33706782 PMCID: PMC7953645 DOI: 10.1186/s13054-021-03519-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 02/26/2021] [Indexed: 01/08/2023]
Affiliation(s)
- Astrid De Bruyn
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium
| | - Lies Langouche
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium
| | - Sarah Vander Perre
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium
| | - Jan Gunst
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium
| | - Greet Van den Berghe
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
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25
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Abstract
PURPOSE OF REVIEW To review the mechanisms how intermittent feeding regimens could be beneficial in critically ill patients. RECENT FINDINGS Large randomized controlled trials (RCTs) have failed to demonstrate consistent benefit of early, enhanced nutritional support to critically ill patients, and some trials even found potential harm. Although speculative, the absence of a clear benefit could be explained by the continuous mode of feeding in these trials, since intermittent feeding regimens had health-promoting effects in healthy animals and humans through mechanisms that also appear relevant in critical illness. Potential protective mechanisms include avoidance of the muscle-full effect and improved protein synthesis, improved insulin sensitivity, better preservation of circadian rhythm, and fasting-induced stimulation of autophagy and ketogenesis. RCTs comparing continuous versus intermittent feeding regimens in critically ill patients have shown mixed results, albeit with different design and inclusion of relatively few patients. In all studies, the fasting interval was relatively short (4-6 h maximum), which may be insufficient to develop a full fasting response and associated benefits. SUMMARY These findings open perspectives for the design and clinical validation of intermittent feeding regimens for critically ill patients. The optimal mode and duration of the fasting interval, if any, remain unclear.
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Affiliation(s)
- Zudin Puthucheary
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London
- Adult Critical Care Unit, Royal London Hospital, London, UK
| | - Jan Gunst
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
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