Bench-to-bedside review: Metabolism and nutrition

Acute kidney injury (AKI) develops mostly in the context of critical illness and multiple organ failure, characterized by alterations in substrate use, insulin resistance, and hypercatabolism. Optimal nutritional support of intensive care unit patients remains a matter of debate, mainly because of a lack of adequately designed clinical trials. Most guidelines are based on expert opinion rather than on solid evidence and are not fundamentally different for critically ill patients with or without AKI. In patients with a functional gastrointestinal tract, enteral nutrition is preferred over parenteral nutrition. The optimal timing of parenteral nutrition in those patients who cannot be fed enterally remains controversial. All nutritional regimens should include tight glycemic control. The recommended energy intake is 20 to 30 kcal/kg per day with a protein intake of 1.2 to 1.5 g/kg per day. Higher protein intakes have been suggested in patients with AKI on continuous renal replacement therapy (CRRT). However, the inadequate design of the trials does not allow firm conclusions. Nutritional support during CRRT should take into account the extracorporeal losses of glucose, amino acids, and micronutrients. Immunonutrients are the subject of intensive investigation but have not been evaluated specifically in patients with AKI. We suggest a protocolized nutritional strategy delivering enteral nutrition whenever possible and providing at least the daily requirements of trace elements and vitamins

Clinical nutrition issues in 2022: What is missing to trust supplemental parenteral nutrition (SPN) in ICU patients?

Clinical nutrition; Intensive care unit; Nutrition careNutrició clínica; Unitat de cures intensives; Cura de la nutricióNutrición Clínica; Unidad de cuidados intensivos; Cuidado de la nutriciónA multidisciplinary group of international physicians involved in the medical nutrition therapy (MNT) of adult critically ill patients met to discuss the value, role, and open questions regarding supplemental parenteral nutrition (SPN) along with oral or enteral nutrition (EN), particularly in the intensive care unit (ICU) setting. This manuscript summarizes the discussions and results to highlight the importance of SPN as part of a comprehensive approach to MNT in critically ill adults and for researchers to generate new evidence based on well-powered randomized controlled trials (RCTs). The experts agreed on several key points: SPN has shown clinical benefits, resulting in this strategy being included in American and European guidelines. Nevertheless, its use is heterogeneous across European countries, due to the persistence of uncertainties, such as the optimal timing and the risk of overfeeding in absence of indirect calorimetry (IC), which results in divergent opinions and barriers to SPN implementation. Education is also insufficient. The experts agreed on actions needed to increase evidence quality on SPN use in specific patients at a given time point during acute critical illness or recovery.The organization of the Virtual Meeting that motivated this publication was funded by Baxter Healthcare SA. The authors received no financial support for the research, authorship, and/or publication of this article. MPC receives funding from the Research Foundation Flanders (FWO) (Grant No. 1832817N) and Onderzoeksraad, KU Leuven (Grant No. C24/17/070) and from the Private Charity Organization “Help Brandwonden Kids

Clinical nutrition issues in 2022: What is missing to trust supplemental parenteral nutrition (SPN) in ICU patients?

A multidisciplinary group of international physicians involved in the medical nutrition therapy (MNT) of adult critically ill patients met to discuss the value, role, and open questions regarding supplemental parenteral nutrition (SPN) along with oral or enteral nutrition (EN), particularly in the intensive care unit (ICU) setting. This manuscript summarizes the discussions and results to highlight the importance of SPN as part of a comprehensive approach to MNT in critically ill adults and for researchers to generate new evidence based on well-powered randomized controlled trials (RCTs). The experts agreed on several key points: SPN has shown clinical benefts, resulting in this strategy being included in American and European guidelines. Nevertheless, its use is heterogeneous across European countries, due to the persistence of uncertainties, such as the optimal timing and the risk of overfeeding in absence of indirect calorimetry (IC), which results in divergent opinions and barriers to SPN implementation. Education is also insufcient. The experts agreed on actions needed to increase evidence quality on SPN use in specifc patients at a given time point during acute critical illness or recovery.MPC receives funding from the Research Foundation Flanders (FWO) (Grant No. 1832817N) and Onderzoeksraad, KU Leuven (Grant No. C24/17/070) and from the Private Charity Organization “Help Brandwonden Kids.info:eu-repo/semantics/publishedVersio

Plasma and red blood cell concentrations of zinc, copper, selenium and magnesium in the first week of paediatric critical illness

Background &amp; aims: Critically ill children are at risk of micronutrient deficiencies, which might lead to poor clinical outcomes. However, the interpretation of micronutrient concentrations in plasma is complicated due to age-dependent and critical illness-dependent changes. Certain red blood cell (RBC) concentrations might reflect the overall body status more reliably than plasma levels in the presence of systemic inflammatory response. This study longitudinally examined micronutrient concentrations in both plasma and RBC in critically ill children. Methods: This secondary analysis of the PEPaNIC RCT investigated the impact of early versus late initiation of parenteral macronutrient supplementation in critically ill children. All children received micronutrients when EN was insufficient (&lt;80 % energy requirements). Blood samples were obtained on days 1, 3, 5 and 7 of Paediatric Intensive Care Unit (PICU) admission. Inductively coupled plasma mass spectrometry was used to measure zinc, selenium, and copper in plasma and selenium, copper, and magnesium in RBCs. Plasma magnesium was measured with colorimetric detection. Micronutrient concentrations were compared with age-specific reference values in healthy children and expressed using Z-scores. Changes in micronutrient concentrations over time were examined using the Friedman and post hoc Wilcoxon signed-rank tests. Results:For 67 critically ill children, median (Q1; Q3) age 9.5 (5.5; 13.2) years, PIM3 score −2.3 (−3.1; −0.8), samples were available at various time points during their PICU stay. For 22 patients, longitudinal samples were available. On day 1, the median plasma Z-score for zinc was −5.2 (−5.2; −2.9), copper −1.6 (−2.9; −0.2), selenium −2.6 (−3.8; −1.0), magnesium −0.2 (−1.6; 1.3), and median RBC Z-score for copper was 0.5 (−0.1; 1.3), selenium −0.3 (−1.1; 0.7), magnesium 0.2 (−0.4; 1.3). In the longitudinal analysis, plasma zinc was significantly higher on day 5 (Z-score −3.2 (−4.6; −1.4)) than on day 1 (Z-score −5.2 (−5.2; −3.0), p = 0.032), and plasma magnesium was significantly higher on day 3 (Z-score 1.1 (−0.7; 4.0)) than on day 1 (Z-score −0.3 (−1.6; 0.5), p = 0.018). Plasma copper and selenium remained stable, and the RBC concentrations of all micronutrients remained stable during the first five days. Conclusions: Most patients had low plasma zinc, copper and selenium concentrations in the first week of their PICU stay, whereas they had normal to high RBC concentrations. More research is needed to examine the relationships between micronutrients and clinical outcome.</p

Metabolic and nutritional support of critically ill patients: consensus and controversies.

The results of recent large-scale clinical trials have led us to review our understanding of the metabolic response to stress and the most appropriate means of managing nutrition in critically ill patients. This review presents an update in this field, identifying and discussing a number of areas for which consensus has been reached and others where controversy remains and presenting areas for future research. We discuss optimal calorie and protein intake, the incidence and management of re-feeding syndrome, the role of gastric residual volume monitoring, the place of supplemental parenteral nutrition when enteral feeding is deemed insufficient, the role of indirect calorimetry, and potential indications for several pharmaconutrients