[DGEM Guideline "Clinical Nutrition in Critical Care Medicine" - short version]

[Iron supplementation in patients with chronic inflammatory bowel disease: recommendations for a practical approach]

Iron deficiency is the predominant cause of anemia. Iron deficiency anemia plays a major role, especially in patients with inflammatory bowel disease (IBD), and is the most common extraintestinal manifestation and IBD-associated systemic complication. The presence of anemia leads to a reduction in quality of life in patients with IBD associated with limitations in physical, emotional, and cognitive function. In addition, it is associated with an increased hospitalization rate. For this reason, iron supplementation is of particular importance. Oral and intravenous iron supplements are used to treat iron deficiency. Due to the lack of absorption and gastrointestinal side effects of oral substitution, intravenous supplementation is becoming increasingly important. However, there are still certain concerns about intravenous administration.With the help of this review, we want to address the topic of iron substitution in patients with IBD, summarize current guideline recommendations, and provide a practical approach.

[Immunometabolism in Sepsis]

Immunometabolism is a fascinating field of research that investigates the interactions between metabolic processes and the immune response. This intricate connection plays a pivotal role in regulating inflammatory reactions and consequently exerts a significant impact on the course of sepsis. The proinflammatory response during an immune reaction is closely tied to a high energy demand in immune cells. As a result, proinflammatory immune cells rapidly require substantial amounts of energy in the form of ATP, necessitating a fundamental and swift shift in their metabolism, i.e., their means of generating energy. This entails a marked increase in glycolysis within the proinflammatory response, thereby promptly meeting the energy requirements and providing essential metabolic building blocks for the biosynthesis of macromolecules. Alongside glycolysis, there is heightened activity in the pentose phosphate pathway (PPP). The PPP significantly contributes to NADPH production within the cell, thus maintaining redox equilibrium. Elevated PPP activity consequently leads to an increased NADPH level, resulting in enhanced production of reactive oxygen species (ROS) and nitric oxide (NO). While these molecules are crucial for pathogen elimination, an excess can also induce tissue damage. Simultaneously, there are dual interruptions in the citric acid cycle. In the cellular resting state, the citric acid cycle acts as a sort of "universal processor", where metabolic byproducts of glycolysis, fatty acid breakdown, and amino acid degradation are initially transformed into NADH and FADH2, subsequently yielding ATP. While the citric acid cycle and its connected oxidative phosphorylation predominantly generate energy at rest, it becomes downregulated in the proinflammatory phase of sepsis. The two interruptions lead to an accumulation of citrate and succinate within cells, reflecting mitochondrial dysfunction. Additionally, the significantly heightened glycolysis through fermentation yields lactate, a pivotal metabolite for sepsis diagnosis and prognosis. Conversely, cells in an anti-inflammatory state revert to a metabolic profile akin to the resting state: Glycolysis is attenuated, PPP is suppressed, and the citric acid cycle is reactivated. Of particular interest is that not only does the immune reaction influence metabolic pathways, but this connection also operates in reverse. Thus, modulation of metabolic pathways also modulates the immunity of the corresponding cell and thereby the state of the immune system itself. This could potentially serve as an intriguing avenue in sepsis therapy.

[Guideline-conform treatment of sepsis]

The time to administration of broad-spectrum antibiotics and (secondarily) to the initiation of hemodynamic stabilization are the most important factors influencing survival of patients with sepsis and septic shock; however, the basic prerequisite for the initiation of an adequate treatment is that a suspected diagnosis of sepsis is made first. Therefore, the treatment of sepsis, even before it has begun, is an interdisciplinary and interprofessional task. This article provides an overview of the current state of the art in sepsis treatment and points towards new evidence that has the potential to change guideline recommendations in the coming years. In summary, the following points are critical: (1) sepsis must be diagnosed as soon as possible and the implementation of a source control intervention (in case of a controllable source) has to be implemented as soon as (logistically) possible. (2) In general, intravenous broad-spectrum antibiotics should be given within the first hour after diagnosis if sepsis or septic shock is suspected. In organ dysfunction without shock, where sepsis is a possible but unlikely cause, the results of focused advanced diagnostics should be awaited before a decision to give broad-spectrum antibiotics is made. If it is not clear within 3 h whether sepsis is the cause, broad-spectrum antibiotics should be given when in doubt. Administer beta-lactam antibiotics as a prolonged (or if therapeutic drug monitoring is available, continuous) infusion after an initial loading dose. (3) Combination treatment with two agents for one pathogen group should remain the exception (e.g. multidrug-resistant gram-negative pathogens). (4) In the case of doubt, the duration of anti-infective treatment should rather be shorter than longer. Procalcitonin can support the clinical decision to stop (not to start!) antibiotic treatment! (5) For fluid treatment, if hypoperfusion is present, the first (approximately) 2L (30 ml/kg BW) of crystalloid solution is usually safe and indicated. After that, the rule is: less is more! Any further fluid administration should be carefully weighed up with the help of dynamic parameters, the patient's clinical condition and echo(cardio)graphy.

Quality appraisal of clinical nutrition practice guidelines for critically ill adult patients: a systematic review using the Advancing Guideline Development, Reporting and Evaluation in Health Care instrument II (AGREE-II) and AGREE-Recommendation Excellence (AGREE-REX)

Nutritional therapy should follow evidence-based practice, thus several societies regarding nutrition and critical care have developed specific Clinical Practice Guidelines (CPG). However, to be regarded as trustworthy, the quality of the CPG for critically ill patients and its recommendations need to be high. This systematic review aimed to appraise the methodology and recommendations of nutrition CPG for critically ill patients. We performed a systematic review (protocol number CRD42020184199) with literature search conducted on PubMed, Embase, Cochrane Library and other four specific databases of guidelines up to October 2021. Two reviewers, independently, assessed titles and abstracts and potentially eligible full-text reports to determine eligibility and subsequently four reviewers appraised the guidelines quality using the Advancing Guideline Development, Reporting and Evaluation in Health Care instrument II (AGREE-II) and AGREE-Recommendation Excellence (AGREE-REX). Ten CPG for nutrition in critically ill patients were identified. Only Academy of Nutrition and Dietetics and European Society of Intensive Care Medicine had a total acceptable quality and were recommended for daily practice according AGREE-II. None of the CPG recommendations had an overall quality score above 70 %, thus being classified as moderate quality according AGREE-REX. The methodological evaluation of the critically ill adult patient CPG revealed significant discrepancies and showed a need for improvement in its development and/or reporting. In addition, recommendations about nutrition care process presented a moderate quality.

[Perioperative nutritional supplementation-what is really evidence based?]

For patients undergoing major surgery, perioperative management according to an early recovery after surgery (ERAS) protocol focusing on early oral food intake is the strategy of choice. So-called perioperative nutritional (artificial) support now seems to be very traditional and outdated. Nevertheless, even in an overweight and obese society the prevalence of combined malnutrition and/or sarcopenia should not be underestimated. This results in the necessity for identification of patients at metabolic risk and the indications for nutritional therapy. This article provides a review of the current concepts of perioperative nutritional supplementation and discusses the available evidence and guideline recommendations.

Nutritional Assessment in Older Adults : MNA® 25 years of a Screening Tool and a Reference Standard for Care and Research; What Next?

A tool to assess nutritional status in older persons was really needed. It took 5 years to design the MNA® (Mini Nutrition Assessment) tool, complete the first validations studies both in Europe and in the U.S. and to publish it. After the full MNA®, the MNA® short form and the self-MNA® have been validated. As well as Chinese and other national MNA® forms. Now more than 2000 clinical research have used the MNA® all over the world from community care to hospital. At least 22 Expert groups included the MNA® in new clinical practice guidelines, national or international registries. The MNA® is presently included in almost all geriatric and nutrition textbook and part of the teaching program for medicine and other health care professional worldwide. The urgent need is to target the frail older adults more likely to have weight loss and poor appetite and to prevent frailty and weight loss in the robust. We present in this paper the review of 25 years of clinical research and practice using the MNA® worldwide.

Metabolic support in the critically ill: a consensus of 19

Metabolic alterations in the critically ill have been studied for more than a century, but the heterogeneity of the critically ill patient population, the varying duration and severity of the acute phase of illness, and the many confounding factors have hindered progress in the field. These factors may explain why management of metabolic alterations and related conditions in critically ill patients has for many years been guided by recommendations based essentially on expert opinion. Over the last decade, a number of randomized controlled trials have been conducted, providing us with important population-level evidence that refutes several longstanding paradigms. However, between-patient variation means there is still substantial uncertainty when translating population-level evidence to individuals. A cornerstone of metabolic care is nutrition, for which there is a multifold of published guidelines that agree on many issues but disagree on others. Using a series of nine questions, we provide a review of the latest data in this field and a background to promote efforts to address the need for international consistency in recommendations related to the metabolic care of the critically ill patient. Our purpose is not to replace existing guidelines, but to comment on differences and add perspective.

Standardized nutritional supply versus individual nutritional assessment: Impact on weight changes, complications and functional outcome from neurological early rehabilitation

BACKGROUND & AIMS

Approximately 55% of neurological and neurosurgical early rehabilitation (NNER) patients are in need of enteral nutrition, but long-term nutritional assessment of these critically ill patients is suboptimal. Therefore, this study analyzed the effect of an individual nutritional assessment on weight changes during rehabilitation and impact on complications and functional outcome.

METHODS

170 NNER patients on enteral nutrition were enrolled in the study. According to the initial ward, patients were assigned to receive standardized enteral nutrition (n = 107, control group) or an individual nutritional assessment (n = 63, intervention group). Weight changes, complications, assessment of the functional outcome (Early Rehabilitation Index, Barthel Index, Early Rehabilitation Barthel Index) and the length of stay were recorded and compared between groups using non-parametric tests for non-paired samples (Mann-Whitney U test for metric data or the χ² test for categorical data) or paired samples (Wilcoxon test). In addition, daily energy requirement was calculated and compared with daily intake. Correlation analysis by Spearman was performed to investigate linear relationship between weight changes and the difference of administered and calculated calories in both study groups.

RESULTS

A weight loss was observed in the control group, whereas the weight of the intervention group remained stable over time. The difference between calculated and administered calories correlated with weight changes in the control group. Regarding complications during rehabilitation, control patients showed more frequently impaired diuresis. In addition, control patients were suffering longer from diarrhea than patients of the intervention group. Both groups improved in functional status to a comparable degree. Relationships between these improvements and weight changes or administered calories could not be found.

CONCLUSIONS

Individual nutritional assessment had not an additional affect for the improvement of functional outcome or the prevention of complications. However, weight turned out to be more stable and signs of nutritional incompatibilities are less frequent among patients being treated with an individualized nutritional assessment.