Enteral versus parenteral early nutrition in ventilated adults with shock: a randomised, controlled, multicentre, open-label, parallel-group study (NUTRIREA-2)

Nutrition Management for Critically Ill Adult Patients Requiring Non-Invasive Ventilation: A Scoping Review

Nutrition management is a core component of intensive care medicine. Despite the increased use of non-invasive ventilation (NIV) for the critically ill, a paucity of evidence on nutrition management precludes recommendations for clinical practice. A scope of the available literature is required to guide future research on this topic. Database searches of MEDLINE, Embase, Scopus, Web of Science, and Google Scholar were conducted to identify original research articles and available grey literature in English from 1 January 1990 to 17 November 2021 that included adult patients (≥16 years) receiving NIV within an Intensive Care Unit. Data were extracted on: study design, aim, population, nutrition concept, context (ICU type, NIV: use, duration, interface), and outcomes. Of 1730 articles, 16 met eligibility criteria. Articles primarily included single-centre, prospective, observational studies with only 3 randomised controlled trials. Key concepts included route of nutrition (n = 7), nutrition intake (n = 4), energy expenditure (n = 2), nutrition status (n = 1), and nutrition screening (n = 1); 1 unpublished thesis incorporated multiple concepts. Few randomised clinical trials that quantify aspects of nutrition management for critically ill patients requiring NIV have been conducted. Further studies, particularly those focusing on the impact of nutrition during NIV on clinical outcomes, are required to inform clinical practice.

Early supplemental parenteral nutrition for the achievement of nutritional goals in subarachnoid hemorrhage patients: An observational cohort study

Purpose

Enteral nutrition (EN) often fails to achieve nutritional goals in neurocritical care patients. We sought to investigate the safety and utility of supplemental parenteral nutrition (PN) in subarachnoid hemorrhage (SAH) patients.

Materials and methods

Data of 70 consecutive patients with non-traumatic SAH admitted to the neurological intensive care unit of a tertiary referral center were prospectively collected and retrospectively analyzed. We targeted the provision of 20–25 kilocalories per kilogram bodyweight per day (kcal/kg/d) by enteral nutrition. Supplemental PN was given when this target could not be reached. Nutritional data were analyzed for up to 14 days of ICU stay. Hospital complications were tested for associations with impaired enteral feeding. The amounts of EN and PN were tested for associations with the level of protein delivery and functional outcome. Repeated measurements within subjects were handled utilizing generalized estimating equations.

Results

Forty (27 women and 13 men) of 70 screened patients were eligible for the analysis. Median age was 61 (IQR 49–71) years, 8 patients (20%) died in the hospital. Thirty-six patients (90%) received PN for a median duration of 8 (IQR 4–12) days. The provision of 20 kcal/kg by EN on at least 1 day of ICU stay was only achieved in 24 patients (60%). Hydrocephalus (p = 0.020), pneumonia (p = 0.037) and sepsis (p = 0.013) were associated with impaired enteral feeding. Neither the amount nor the duration of PN administration was associated with an increased risk of severe complications or poor outcome. Supplemental PN was associated with significantly increased protein delivery (p<0.001). In patients with sepsis or pneumonia, there was an association between higher protein delivery and good functional outcome (p<0.001 and p = 0.031), but not in the overall cohort (p = 0.08).

Conclusions

Enteral feeding was insufficient to achieve nutritional goals in subarachnoid hemorrhage patients. Supplemental PN was safe and associated with increased protein delivery. A higher protein supply was associated with good functional outcome in patients who developed sepsis or pneumonia.

Enteral Nutrition in Critically Ill Patients Under Vasoactive Drug Therapy. The NUTRIVAD Study

BACKGROUND

Enteral nutrition (EN) in critically ill patients requiring vasoactive drug (VAD) support is controversial. This study assesses the tolerability and safety of EN in such patients.

METHODS

This prospective observational study was conducted in 23 ICUs over 30 months. Inclusion criteria were a need for VAD and/or mechanic circulatory support (MCS) over a minimum of 48 h, a need for at least 48 h of mechanical ventilation, an estimated life expectancy longer than 72 h, and at least 72 h of ICU stay. Patients with refractory shock were excluded. EN was performed according to established protocols during which descriptive, daily hemodynamic and efficacy and safety data were collected. An independent research group conducted the statistical analysis.

RESULTS

Of 200 patients included, 30 (15%) required MCS and 145 (73%) met early multiorgan dysfunction criteria. Mortality was 24%. Patients needed a mean dose of norepinephrine in the first 48 h of 0.71 μg/kg/min (95%CI: 0.63-0.8) targeting a mean arterial pressure of 68 mmHg (95%CI: 67-70) during the first 48 h. EN was started 34 h (95%CI: 31-37) after ICU admission. Mean energy and protein delivered by EN/patient/day were 1159 Kcal (95%CI: 1098-1220) and 55.6 g (52.4-58.7) respectively. Daily energy balance during EN/patient/day was -432 (95%CI: -496 to -368). 154 (77%) patients experienced EN-related complications. However, severe complications such as mesenteric ischemia were recorded in only 1 patient (0.5%).

CONCLUSIONS

EN in these patients seems feasible, safe and unrelated to serious complications. Reaching the energy target only through EN is difficult.

CLINICAL RELEVANCY STATEMENT

Enteral nutrition (EN) in critically ill patients requiring vasoactive drugs (VAD) is currently a subject of controversy. Factors such as when to start EN, dosing, monitoring, or whether to avoid EN altogether are a real challenge because of its link to a risk of bowel ischemia. We describe our experience with EN in 200 critically ill patients on mechanical ventilation and requiring VAD. Under adequate supervision, EN proved feasible and safe. Our findings require confirmation in clinical intervention trials. This article is protected by copyright. All rights reserved.

Small bowel feeding: do you pay the price for bypassing the stomach?

PURPOSE OF REVIEW

Hydration and nutritional support is a vital part of medical care, thus a clear understanding of the optimal approach is vital for medical professionals. This is a particularly pertinent issue for patients admitted to a critical care setting. This article aims to define the advantages and disadvantages of gastric and postpyloric feeding in the critical care setting, thus aiding decision-making for clinicians.

RECENT FINDINGS

Within the article, the main themes covered are those relating to enteral feeding tube placement, the impact of enteral feeding route on ventilator-associated pneumonia, optimization of enteral tube feeding in critical care and the impact that a chosen route may have upon gastrointestinal function.

SUMMARY

The value of enteral feeding in critical illness is proven beyond doubt and the simplest approach has long been 'if the gut works, use it'. If gastric feeding is not able to be established or is not tolerated then jejunal feeding should be considered as a preferable alternative to parenteral nutrition. Improving access to service or techniques for postpyloric tube placement would assist in optimizing nutritional support in the critical care setting.

Enteral feeding, even when the gut does not feel very good?

PURPOSE OF REVIEW

To summarize knowledge on the gut function in relation to enteral nutrition.

RECENT FINDINGS

The gut is certainly suffering during critical illness but our understanding of the exact mechanisms involved is limited. Physicians at bedside are lacking tools to identify how well or bad the gut is doing and whether the gut is responding adequately to critical illness. Sensing nutrition as a signal is important for the gut and microbiome. Enteral nutrition has beneficial effects for the gut perfusion and function. However, early full enteral nutrition in patients with shock was associated with an increased number of rare but serious complications.

SUMMARY

Whenever synthesizing knowledge in physiology and available evidence in critically ill, we suggest that enteral nutrition has beneficial effects but may turn harmful if provided too aggressively. Contraindications to enteral nutrition are listed in recent guidelines. For patients with gastrointestinal dysfunction but without these contraindications, we suggest considering early enteral nutrition as a signal to the gut and to the body rather than an energy and protein provision. With this rationale, we think that low dose of enteral nutrition could and probably should be provided also when the gut does not feel very good. Understanding the feedback from the gut in response to enteral nutrition would be important, however, monitoring tools are currently limited to clinical assessment only.

Nutrition priorities in obese critically ill patients

PURPOSE OF REVIEW

During critical illness, several neuroendocrine, inflammatory, immune, adipokine, and gastrointestinal tract hormone pathways are activated; some of which are more intensified among obese compared with nonobese patients. Nutrition support may mitigate some of these effects. Nutrition priorities in obese critically ill patients include screening for nutritional risk, estimation of energy and protein requirement, and provision of macronutrients and micronutrients.

RECENT FINDINGS

Estimation of energy requirement in obese critically ill patients is challenging because of variations in body composition among obese patients and absence of reliable predictive equations for energy expenditure. Whereas hypocaloric nutrition with high protein has been advocated in obese critically ill patients, supporting data are scarce. Recent studies did not show differences in outcomes between hypocaloric and eucaloric nutrition, except for better glycemic control. Sarcopenia is common among obese patients, and the provision of increased protein intake has been suggested to mitigate catabolic changes especially after the acute phase of critical illness. However, high-quality data on high protein intake in these patients are lacking. Micronutrient deficiencies among obese critically ill patients are common but the role of their routine supplementation requires further study.

SUMMARY

An individualized approach for nutritional support may be needed for obese critically ill patients but high-quality evidence is lacking. Future studies should focus on nutrition priorities in this population, with efficient and adequately powered studies.

Factors associated with acute mesenteric ischemia among critically ill ventilated patients with shock: a post hoc analysis of the NUTRIREA2 trial

PURPOSE

Acute mesenteric ischemia (AMI) is a rare, but life-threatening condition occurring among critically ill patients. Several factors have been associated with AMI, but the causal link is debated, most studies being retrospective. Among these factors, enteral nutrition (EN) could be associated with AMI, in particular among patients with shock. We aimed to study the factors independently associated with AMI in a post hoc analysis of the NUTRIREA-2 trial including 2410 critically ill ventilated patients with shock, randomly assigned to receive EN or parenteral nutrition (PN).

METHODS

Post hoc analysis of the NUTRIREA-2 trial was conducted. Ventilated adults with shock were randomly assigned to receive EN or PN. AMI was assessed by computed tomography, endoscopy, or laparotomy. Factors associated with AMI were studied by univariate and multivariate analysis.

RESULTS

2410 patients from 44 French intensive care units (ICUs) were included in the study: 1202 patients in the enteral group and 1208 patients in the parenteral group. The median age was 67 [58-76] years, with 67% men, a SAPS II score of 59 [46-74], and a medical cause for ICU admission in 92.7%. AMI was diagnosed among 24 (1%) patients, mainly by computed tomography (79%) or endoscopy (38%). The mechanism of AMI was non-occlusive mesenteric ischemia (n = 12), occlusive (n = 4), and indeterminate (n = 8). The median duration between inclusion in the trial and AMI diagnosis was 4 [1-11] days. Patients with AMI were older, had a higher SAPS II score at ICU admission, had higher plasma lactate, creatinine, and ASAT concentrations and lower hemoglobin concentration, had more frequently EN, dobutamine, and CVVHDF at inclusion, developed more frequently bacteremia during ICU stay, and had higher 28-day and 90-day mortality rates compared with patients without AMI. By multivariate analysis, AMI was independently associated with EN, dobutamine use, SAPS II score ≥ 62 and hemoglobin concentration ≤ 10.9 g/dL.

CONCLUSION

Among critically ill ventilated patients with shock, EN, dobutamine use, SAPS II score ≥ 62 and hemoglobin ≤ 10.9 g/dL were independently associated with AMI. Among critically ill ventilated patients requiring vasopressors, EN should be delayed or introduced cautiously in case of low cardiac output requiring dobutamine and/or in case of multiple organ failure with high SAPS II score.

Actively implementing an evidence-based feeding guideline for critically ill patients (NEED): a multicenter, cluster-randomized, controlled trial

BACKGROUND

Previous cluster-randomized controlled trials evaluating the impact of implementing evidence-based guidelines for nutrition therapy in critical illness do not consistently demonstrate patient benefits. A large-scale, sufficiently powered study is therefore warranted to ascertain the effects of guideline implementation on patient-centered outcomes.

METHODS

We conducted a multicenter, cluster-randomized, parallel-controlled trial in intensive care units (ICUs) across China. We developed an evidence-based feeding guideline. ICUs randomly allocated to the guideline group formed a local "intervention team", which actively implemented the guideline using standardized educational materials, a graphical feeding protocol, and live online education outreach meetings conducted by members of the study management committee. ICUs assigned to the control group remained unaware of the guideline content. All ICUs enrolled patients who were expected to stay in the ICU longer than seven days. The primary outcome was all-cause mortality within 28 days of enrollment.

RESULTS

Forty-eight ICUs were randomized to the guideline group and 49 to the control group. From March 2018 to July 2019, the guideline ICUs enrolled 1399 patients, and the control ICUs enrolled 1373 patients. Implementation of the guideline resulted in significantly earlier EN initiation (1.20 vs. 1.55 mean days to initiation of EN; difference - 0.40 [95% CI - 0.71 to - 0.09]; P = 0.01) and delayed PN initiation (1.29 vs. 0.80 mean days to start of PN; difference 1.06 [95% CI 0.44 to 1.67]; P = 0.001). There was no significant difference in 28-day mortality (14.2% vs. 15.2%; difference - 1.6% [95% CI - 4.3% to 1.2%]; P = 0.42) between groups.

CONCLUSIONS

In this large-scale, multicenter trial, active implementation of an evidence-based feeding guideline reduced the time to commencement of EN and overall PN use but did not translate to a reduction in mortality from critical illness.

TRIAL REGISTRATION

ISRCTN, ISRCTN12233792 . Registered November 20th, 2017.

Nutrition support for acute kidney injury 2020-consensus of the Taiwan AKI task force

BACKGROUND

We used evidence-based medicine to suggest guidelines of nutritional support for Taiwanese patients with acute kidney injury (AKI).

METHODS

Our panel reviewed the medical literature in group meetings to reach a consensus on answering clinical questions related to the effects of the nutritional status, energy/protein intake recommendations, timing of enteral, and parenteral nutrition supplementation.

RESULTS

Markers of the nutritional status of serum albumin, protein intake, and nitrogen balance had positive relationships with low mortality. A forest plot of the comparison of mortality between a body mass index (BMI) of <18.5 and ≥18.5 kg/m2 was produced using data from seven observational studies which showed that a lower BMI was associated with higher mortality. The energy recommendation of 20-30 kcal/kg body weight (BW)/day was determined to be valid for all stages of AKI. The protein recommendation for noncatabolic AKI patients is 0.8-1.0 g/kg BW/day, and 1.2-2.0 g/kg BW/day is the same as that for the underlying disease that is causing AKI. Protein intake should be at least 1.5 g/kg BW/day and up to 2.5 g/kg BW/day in patients receiving continuous renal replacement therapy. Considering that patients with AKI often have other critical comorbid situations, early enteral nutrition (EN) is suggested, and parenteral nutrition is needed when >60% energy and protein requirements cannot be met via the enteral route in 7-10 days. Low energy intake is suggested in critically ill patients with AKI, which should gradually be increased to meet 80%-100% of the energy target.

CONCLUSION

By examining evidence-based research, we provide practicable nutritional guidelines for AKI patients.

When is parenteral nutrition indicated?

The indications and contraindications of parenteral nutrition (PN) are discussed in view of recent clinical findings. For decades, PN has been restricted to patients unable to tolerate enteral nutrition (EN) intake owing to the perceived risk of severe side-effects. The evolution of the PN substrate composition and delivery of nutrition via all-in-one bags has dramatically improved the application prospects of PN. Recent studies show similar complication rates of nutrition therapy administered through enteral and intravenous routes. Therefore, indications of PN have, based on evidence, extended beyond complete gastrointestinal (GI) failure to include conditions such as insufficient EN generating persistent negative energy balance and insufficient protein intakes, malabsorption, or specific needs that are impossible to cover with EN feeds.

Reversal of Feed Intolerance by Prokinetics Improves Survival in Critically Ill Cirrhosis Patients

BACKGROUND AND AIMS

Feed intolerance (FI) is common in cirrhosis patients in intensive care units (ICU). Prokinetics are the first line treatment for FI but their efficacy and safety in critically ill patient with cirrhosis is unknown. We evaluated the role of prokinetics in reversal of FI and clinical outcomes.

METHODS

Consecutive patients admitted in ICU developing new-onset FI, were randomized to receive either intravenous metoclopramide (Gr.A, n = 28), erythromycin (Gr.B, n = 27) or placebo (Gr.C, n = 28). FI was defined with the presence of 3 of 5 variables- absence of bowel sounds, gastric residual volume ≥ 500 ml, vomiting, diarrhoea and bowel distension. Primary end-point was complete resolution of FI (≥ 3 variables resolved) within 24-h and secondary end-points included resolution within 72-h and survival at 7-days.

RESULTS

Of the 1030 ICU patients, 201 (19.5%) developed FI and 83 patients were randomized. Baseline parameters between the groups were comparable. Complete resolution at 24-h was higher in Gr.A (7.14%) and B (22.2%) than C (0%, p = 0.017). Overall, 58 (69.9%) patients achieved resolution within 72 h, more with metoclopramide (n = 24, 85.7%) and erythromycin (n = 25, 92.6%) than with placebo (n = 9, 32.1%, p < 0.001). The 7-day survival was better in patients who achieved resolution within 72-h (65.5 vs. 36%, p = 0.011) than non-responders. High lactate (OR-3.32, CI-1.45-7.70, p = 0.005), shock at baseline (OR-6.34, CI-1.67-24.1, p = 0.007) and resolution of FI within 72 h (OR-0.11, CI, 0.03-0.51, p = 0.04) predicted 7-day mortality.

CONCLUSIONS

FI is common in critically-ill cirrhosis patients and non-resolution carries high mortality. Early recognition and treatment with prokinetics is recommended to improve short-term survival.

Does Route of Full Feeding Affect Outcome among Ventilated Critically Ill COVID-19 Patients: A Prospective Observational Study

The outbreak of the new coronavirus strain SARS-CoV-2 (COVID-19) highlighted the need for appropriate feeding practices among critically ill patients admitted to the intensive care unit (ICU). This study aimed to describe feeding practices of intubated COVID-19 patients during their second week of hospitalization in the First Department of Critical Care Medicine, Evaggelismos General Hospital, and evaluate potential associations with all cause 30-day mortality, length of hospital stay, and duration of mechanical ventilation. We enrolled adult intubated COVID-19 patients admitted to the ICU between September 2020 and July 2021 and prospectively monitored until their hospital discharge. Of the 162 patients analyzed (52.8% men, 51.6% overweight/obese, mean age 63.2 ± 11.9 years), 27.2% of patients used parenteral nutrition, while the rest were fed enterally. By 30 days, 34.2% of the patients in the parenteral group had died compared to 32.7% of the patients in the enteral group (relative risk (RR) for the group receiving enteral nutrition = 0.97, 95% confidence interval = 0.88–1.06, p = 0.120). Those in the enteral group demonstrated a lower duration of hospital stay (RR = 0.91, 95% CI = 0.85-0.97, p = 0.036) as well as mechanical ventilation support (RR = 0.94, 95% CI = 0.89–0.99, p = 0.043). Enteral feeding during second week of ICU hospitalization may be associated with a shorter duration of hospitalization and stay in mechanical ventilation support among critically ill intubated patients with COVID-19.

A guide to enteral nutrition in intensive care units: 10 expert tips for the daily practice

The preferential use of the oral/enteral route in critically ill patients over gut rest is uniformly recommended and applied. This article provides practical guidance on enteral nutrition in compliance with recent American and European guidelines. Low-dose enteral nutrition can be safely started within 48 h after admission, even during treatment with small or moderate doses of vasopressor agents. A percutaneous access should be used when enteral nutrition is anticipated for ≥ 4 weeks. Energy delivery should not be calculated to match energy expenditure before day 4–7, and the use of energy-dense formulas can be restricted to cases of inability to tolerate full-volume isocaloric enteral nutrition or to patients who require fluid restriction. Low-dose protein (max 0.8 g/kg/day) can be provided during the early phase of critical illness, while a protein target of > 1.2 g/kg/day could be considered during the rehabilitation phase. The occurrence of refeeding syndrome should be assessed by daily measurement of plasma phosphate, and a phosphate drop of 30% should be managed by reduction of enteral feeding rate and high-dose thiamine. Vomiting and increased gastric residual volume may indicate gastric intolerance, while sudden abdominal pain, distension, gastrointestinal paralysis, or rising abdominal pressure may indicate lower gastrointestinal intolerance.

Enteral nutrition in septic shock: A pathophysiologic conundrum

Septic shock is a public health burden and defined as a subset of sepsis whereby abnormalities in microcirculatory and cellular metabolism manifest as acute circulatory failure. At the level of the gut, septic shock impairs epithelial barrier function (EBF), and the gut initiates proinflammatory responses contributing to multiple organ dysfunction syndrome. The timing and dose of enteral nutrition (EN) in septic shock remains a conundrum. On the one hand, early EN preserves EBF. On the other hand, serious gastrointestinal complications such as bowel necrosis may limit EN initiation in septic shock. We (1) describe the pathophysiologic conundrum septic shock poses for EN initiation, (2) outline guideline-based recommendations for EN in septic shock, (3) identify the role of parenteral nutrition in septic shock, and (4) identify and appraise postguideline literature on the timing, dose, and titration of EN in septic shock.

Nutrition support for critically ill patients

Nutrition support is an important aspect of the management of critically ill patients. This review highlights the emerging evidence on critical care nutrition and focuses on the pathophysiologic interplay between critical illness, the gastrointestinal tract, and nutrition support and the evidence on the best route, dose, and timing of nutrition. Although indirect calorimetry is recommended to measure energy expenditure, predictive equations are commonly used but are limited by their inaccuracy in individual patients. The current evidence supports early enteral nutrition (EN) in most patients, with a gradual increase in the daily dose over the first week. Delayed EN is warranted in patients with severe shock. According to recent trials, parenteral nutrition seems to be as effective as EN and may be started if adequate EN is not achieved by the first week of critical illness. A high protein dose has been recommended, but the best timing is unclear. Immuno-nutrition should not be routinely provided to critically ill patients. Patients receiving artificial nutrition should be monitored for metabolic derangements. Additional adequately powered studies are still needed to resolve many unanswered questions.

Timing of parenteral nutrition in ICU patients: A transatlantic controversy

BACKGROUND AND AIMS

European and North American guidelines on Parenteral Nutrition (PN) and large Randomized Controlled Trials give divergent advices on nutritional therapeutic strategies for critically ill patients. We therefore investigated differences in therapeutic strategies of clinicians between European and Non-European Intensive Care Units (ICU) regarding start day of PN, preferred route of administration and prescription of total energy targets over the years.

METHODS

In this study 16,032 patients from 1389 different ICUs were included. Data collection was performed in 28 different European and Non-European ICUs from 2007 to 2018 via nutritionDay, a worldwide-standardized one-day multinational cross-sectional audit.

RESULTS

In this analysis an abrupt delay in PN start days was observed in 2011 (7.64 days (4.31; 19.97); p = 0.001) and 2012 (6.41 days (3.1; 9.72); p = 0.001), which was significantly reversed within the following years until 2018. In European, compared to Non-European countries PN prescription was increased (27% versus 13%). Patients from North-America received significantly less kcal per day compared to Europe (-4.3 kcal kg^-1 (-6.9; -1.6); p = 0.001).

CONCLUSIONS

Our study provides further evidence on transatlantic discrepancies in nutritional therapy of ICU patients. Regular audits, such as nutritionDay are substantial for self-reflection of clinical daily practice of intensivists. It is time for worldwide consensus in nutritional therapy by developing worldwide guidelines and supporting standardization in nutrition care of critically ill patients.

Guidelines for the provision of nutrition support therapy in the adult critically Ill patient: American society for parenteral and enteral nutrition

BACKGROUND

New randomized controlled trials have been conducted since publication of the 2016 ASPEN/SCCM critical care nutrition guideline. This guideline updates recommendations for foundational questions central to critical care nutrition support.

METHODS

The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) process was used to develop and summarize evidence for clinical practice recommendations. Clinical outcomes were assessed for (1) higher vs lower energy dose (2) higher vs lower protein dose (3) exclusive isocaloric PN vs EN (4) supplemental PN (SPN) plus EN vs EN alone (5a) mixed oil lipid injectable emulsions (ILE) vs soybean oil, and (5b) Fish oil (FO) containing ILE vs non-FO ILE. To assess safety, weight based energy intake was plotted against hospital mortality when study heterogeneity precluded meaningful Forest plot inferences.

RESULTS

Between 1/1/2001 and 07/15/2020, 2,320 citations were identified and data were abstracted from 39 trials, including 20,578 participants. Patients receiving FO had decreased pneumonia rates of uncertain clinical significance. Otherwise, there were no differences for any outcome in any question. Due to lack in certainty regarding harm, the energy prescription recommendation was decreased to 12-25kcal/kg/day.

CONCLUSION

No differences in clinical outcomes were identified among numerous nutritional interventions, including higher energy or protein intake, isocaloric PN or EN, supplemental PN, or different ILEs. As more consistent critical care nutrition support data become available, more precise recommendations will be possible. In the meantime, clinical judgment and close monitoring are needed. This paper was approved by the ASPEN Board of Directors.  This article is protected by copyright. All rights reserved.

Manejo del abdomen abierto en el paciente crítico en un centro de nivel III de Popayán

Introducción. El abdomen abierto es un recurso útil para el tratamiento de pacientes con patología abdominal compleja, con potencial de complicaciones. El objetivo de este estudio fue adaptar la guía de World Society of Emergency Surgery (WSES) 2018, en un hospital de nivel III de atención de la ciudad de Popayán, Colombia, y comparar los resultados obtenidos con los previos a su implementación. Métodos. Estudio cuasi-experimental en dos mediciones de pacientes con abdomen abierto y estancia en cuidado crítico, durante los meses de abril a octubre de los años 2018 y 2019, antes y después de la adaptación con el personal asistencial de la guía de práctica clínica WSES 2018. Se utilizó estadística descriptiva, prueba de Chi cuadrado y se empleó el software SPSS V.25. Resultados. Se incluyeron 99 pacientes críticos, con una edad media de 53,2 años, con indicación de abdomen abierto por etiología traumática en el 28,3 %, infecciosa no traumática en el 32,3 % y no traumática ni infecciosa en el 37,4 %. La mortalidad global fue de 25,3 %, de los cuales, un 68 % se debieron a causas ajenas a la patología abdominal. Las complicaciones postoperatorias se presentaron en 10 pacientes con infección de sitio operatorio y 9 pacientes con fístula enterocutánea. El uso del doble Viaflex se implementó en un 63,6 %, logrando un cierre de la pared abdominal en el 79,8 % de los casos (p=0,038). Conclusión. El abdomen abierto requiere de un abordaje multidisciplinar. El uso de doble Viaflex es una herramienta simple y efectiva. La implementación de la guía disminuyó el porcentaje de mortalidad, los días de abdomen abierto y la estancia en cuidados intensivos.

Dynamic metabolic changes measured by indirect calorimetry during the early phase of septic shock: a prospective observational pilot study

BACKGROUND AND AIMS

Energy metabolism (energy deficit, substrate consumption) in the early phase of septic shock is not clearly understood. The objective of this study was to describe its evolution using indirect calorimetry.

METHODS

Prospective observational pilot study including ventilated adult patients with septic shock admitted in a surgical intensive care unit (ICU). Metabolic data were collected using the COSMED Q-NRG + ® calorimeter: carbon dioxide production (VCO2), oxygen consumption (VO2), resting energy expenditure (REE), respiratory quotient (RQ) and the rate of substrate utilization (proteins, lipids, and carbohydrates). The main criterion was the evolution of the energy deficit (dE) from D1 to D6.

RESULTS

In total, 34 patients were included and 15 patients (age: 57.6 ± 12.8 years; Simplified Acute Physiology Score II: 52 ± 11) were eligible for final analysis. Time for initiation of nutritional support was 2.5 ± 1.5 days. The dE improved during the study period (slope = 2.9 [1.8; 4.2]; p < 0.001). The REE remained stable during the first week with no significant variation (slope = -0.16 [-1.49; 0.79]; p = 0.78). The RQ remained stable overall (slope = 0.01 [0.00; 0.03]; p = 0.10). The substrates utilization significantly changed at D3 in favor of protein consumption (slope = 6.50 [4.44; 8.85]; p < 0.001) with an overall significant decrease in the consumption of non-protein substrates.

CONCLUSION

Energy deficit improved while REE and RQ remained relatively stable during the first week of ICU stay. The significance of the variations of substrates consumption was unclear. These preliminary results should be further explored with larger studies.

Enteral nutrition and dynamics of citrulline and intestinal fatty acid-binding protein in adult ICU patients

BACKGROUND AND AIMS

Plasma citrulline and intestinal fatty acid binding protein (I-FABP) are biomarkers reflecting enterocyte function and intestinal mucosal injury. The aim was to describe daily dynamics of citrulline and I-FABP concentrations in association with enteral nutrition (EN) in adult ICU patients. We hypothesized that success or failure of EN is reflected by differences in citrulline and I-FABP levels at admission, as well as in daily dynamics over the first week.

METHODS

The present study was a planned sub-study of the iSOFA study (ClinicalTrials.gov Identifier: NCT02613000). With delayed informed consent we included adult (18 years or older) patients admitted for unlimited care to 5 ICUs in Europe. Citrulline and I-FABP were assessed and nutritional data recorded daily during the first week of the patients' ICU stay.

RESULTS

The study included 224 patients with 693 plasma samples analyzed for citrulline and 695 for I-FABP. The median ICU stay was 2 (IQR 1-4) days and 35 patients (15.6 %) stayed in the ICU for ≥ 7 days. The majority of patients (184/224; 82.1 %) received EN or oral nutrition (ON) during their ICU stay, in 164 patients (73.2 %) nutrition was started within 48 h of admission (early enteral or oral nutrition, EEN/ON). Median biomarker concentrations on admission were: citrulline 24.5 (IQR 18.1-31.7) μmol/L and I-FABP 2763 (1326-4805) pg/mL. Reference range for citrulline was 17-46 μmol/L and for I-FABP 377-2049 pg/mL. Patients with EEN/ON demonstrated an increase in citrulline concentrations over the first week in ICU unlike those not receiving EEN/ON (P = 0.049 for the mean log-citrulline values over time between groups) as well as higher average citrulline concentrations. Success of EEN/ON (80 % of caloric target achieved by day 4) was associated with citrulline values increasing from day 4, whereas a slight decrease was observed with unsuccessful EEN/ON. However, these dynamics over time were not statistically significantly different (P = 0.654). Patients with EEN/ON unexpectedly had I-FABP values higher than those without (average values for all days P = 0.004). Median I-FABP values on day 3 were higher with successful EEN/ON (646 (IQR 313-1116) vs 278 (IQR 190-701) pg/mL, P = 0.022).

CONCLUSIONS

EEN/ON was associated with higher values and different dynamics of citrulline over the first week in ICU. No clear difference of measured biomarkers was seen when patients were compared according to success of EEN/ON. Our study does not allow suggesting certain thresholds of citrulline nor I-FABP that could be used for bedside decision-making with regard to EN. This study was a planned sub-study of the iSOFA study (ClinicalTrials.gov Identifier: NCT02613000).

Mortality and overall and specific infection complication rates in patients who receive parenteral nutrition: systematic review and meta-analysis with trial sequential analysis

BACKGROUND

Parenteral nutrition (PN) is an available option for nutritional therapy and is often required in the hospital setting to overcome malnutrition.

OBJECTIVES

The aim of this study was to assess whether PN is associated with an increased risk of mortality or infectious complications in all groups of hospitalized patients compared with those receiving other nutritional support strategies.

METHODS

For this systematic review and meta-analysis MEDLINE, Embase, Cochrane Central, Scopus, clinicaltrials.gov, and Web of Science were searched for randomized controlled trials (RCTs) and observational studies with parallel groups that explored the effect of PN on mortality and infectious complications, published until March 2021. Two independent reviewers extracted the data and assessed the risk of bias. Fixed-effects meta-analysis was performed to compare the groups from RCTs. Trial sequential analysis (TSA) was used to identify whether the results were sufficient to reach definitive conclusions.

RESULTS

Of the 83 included studies that compared patients receiving PN with those receiving other strategies, 67 RCTs were included in the meta-analysis. PN was not associated with a higher risk of mortality (RR: 1.01; 95% CI: 0.95, 1.07). On the other hand, PN was associated with a higher risk of infectious events (RR: 1.23; 95% CI: 1.12, 1.36). PN was specifically associated with abdominal infection and catheter infection. The TSA showed that there were sufficient data to make numerical conclusions about mortality, any infectious event, and abdominal infectious complications.

CONCLUSIONS

This study suggests that although PN is not associated with greater mortality in hospitalized patients, it is associated with infectious complications. Through TSA, definite conclusions about survival and infection rates could be made.This review was registered at www.crd.york.ac.uk/prospero/ as CRD42018075599.

Early versus late enteral nutrition in critically ill patients receiving vasopressor support

BACKGROUND

Outcomes of early enteral nutrition (EEN) in critically ill patients on vasoactive medications remain unclear. We aimed to compare in-hospital outcomes for EEN vs late EN (LEN) in mechanically ventilated patients receiving vasopressor support.

METHODS

This was a retrospective study using the national eICU Collaborative Research Database. Adult patients requiring vasopressor support and mechanical ventilation within 24 h of admission and for ≥2 days were included. Patients with an admission diagnosis that could constitute a contraindication for EEN (eg, gastrointestinal [GI] perforation, GI surgery) and patients with an intensive care unit (ICU) length of stay (LOS) <72 h were excluded. EEN and LEN were defined as tube feeding within 48 h and between 48 h and 1 week (nothing by mouth during the first 48 h) of admission, respectively. Propensity score matching was performed to derive two cohorts receiving EEN and LEN that were comparable for baseline patient characteristics.

RESULTS

Among 1701 patients who met the inclusion criteria (EEN: 1001, LEN: 700), 1148 were included in propensity score-matched cohorts (EEN: 574, LEN: 574). Median time to EN was 29 vs 79 h from admission in the EEN and LEN groups, respectively. There was no significant difference in mortality or hospital LOS between the two nutrition strategies. EEN was associated with shorter ICU LOS, lower need for renal replacement therapy, and lower incidence of electrolyte abnormalities.

CONCLUSION

This study showed no difference in 28-day mortality between EEN and LEN in critically ill patients receiving vasopressor support.

Caloric Intake with High Ratio of Enteral Nutrition Associated with Lower Hospital Mortality for Patients with Acute Respiratory Distress Syndrome Using Prone Position Therapy

Positioning patients in the prone position leads to reduced hospital mortality rates for those with severe acute respiratory distress syndrome (ARDS). What constitutes the optimal feeding strategy for prone patients with ARDS is controversial. We conducted a retrospective study that enrolled 110 prone patients with ARDS in two medical intensive care units (ICUs) from September 2015 to November 2018. Inclusion criteria were as follows: age ≥20 years, diagnosis of respiratory failure requiring mechanical ventilation, diagnosis of ARDS within 72 h of ICU admission, placement in a prone position within the first 7 days of ICU admission, and ICU stay of more than 7 days. Exclusion criteria were as follows: nil per os orders because of gastrointestinal bleeding or hemodynamic instability, and ventilator dependency because of chronic respiratory failure. The consecutive daily enteral nutrition(EN)/EN + parenteral nutrition(PN) ratio could predict hospital mortality rates within the first 7 days of admission when using generalized estimating equations (p = 0.013). A higher average EN/EN + PN ratio within the first 7 days predicted (hazard ratio: 0.97, confidence interval: 0.96-0.99) lower hospital mortality rates. To reduce hospital mortality rates, caloric intake with a higher EN ratio may be considered for patients in prone positions with ARDS.

Development and validation of a predictive model for feeding intolerance in intensive care unit patients with sepsis

BACKGROUND

Feeding intolerance in patients with sepsis is associated with a lower enteral nutrition (EN) intake and worse clinical outcomes. The aim of this study was to develop and validate a predictive model for enteral feeding intolerance in the intensive care unit patients with sepsis.

METHODS

In this dual-center, retrospective, case-control study, a total of 195 intensive care unit patients with sepsis were enrolled from June 2018 to June 2020. Data of 124 patients for 27 clinical indicators from one hospital were used to train the model, and data from 71 patients from another hospital were used to assess the external predictive performance. The predictive models included logistic regression, naive Bayesian, random forest, gradient boosting tree, and deep learning (multilayer artificial neural network) models.

RESULTS

Eighty-six (44.1%) patients were diagnosed with enteral feeding intolerance. The deep learning model achieved the best performance, with areas under the receiver operating characteristic curve of 0.82 (95% confidence interval = 0.74-0.90) and 0.79 (95% confidence interval = 0.68-0.89) in the training and external sets, respectively. The deep learning model showed good calibration; based on the decision curve analysis, the model's clinical benefit was considered useful. Lower respiratory tract infection was the most important contributing factor, followed by peptide EN and shock.

CONCLUSIONS

The new prediction model based on deep learning can effectively predict enteral feeding intolerance in intensive care unit patients with sepsis. Simple clinical information such as infection site, nutrient type, and septic shock can be useful in stratifying a septic patient's risk of EN intolerance.

Exploration of the Curative Effect of Early Enteral Nutrition Nursing on Patients with Severe Acute Pancreatitis and the Improvement of Patients' Mental Health and Inflammation Level

In order to explore the curative effect of early enteral nutrition nursing on patients with severe acute pancreatitis and the improvement of patients' mental health and inflammation levels, this paper compares the curative effect of early enteral nutrition nursing and traditional care on patients with severe acute pancreatitis and the improvement effects of patients' mental health and inflammation levels through controlled trials. Moreover, this paper combines statistical methods for data processing and visually expresses data through statistical graphs and statistical tables. Through the comparison of experiments, it can be seen that the improvement effect in all aspects of patients in the test group is significantly higher than that in the control group. Finally, through the analysis of the test results, it can be known that the use of early enteral nutrition nursing for patients with acute severe acute pancreatitis has a certain effect in improving their nutritional status, regulating immune function, and promoting mental health.

Nonocclusive mesenteric ischemia: A rare but lethal complication of enteral nutrition in critically ill patients

BACKGROUND

The American Society for Parenteral and Enteral Nutrition (ASPEN)/ Society of Critical Care Medicine and the European Society for Clinical Nutrition and Metabolism guidelines recognize that critically ill patients receiving stable, low doses of vasopressors have experienced the advantages of early initiation of enteral nutrition (EN). However, clinical questions remained unanswered including vasopressor combinations associated with complications, the advent of other therapies during hypotensive states, as well as the volume and content of EN that might contribute to the development of a nonocclusive mesenteric ischemia (NOMI).

PRESENTATION

A 68-year old male with a history of hypertension, hyperlipidemia, atrial fibrillation, coronary artery disease with two-vessel bypass grafting, and peripheral vascular disease underwent subtotal excision of an infected right axillofemoral-femoral bypass graft. Postoperatively, EN was held because of hemodynamic instability and postsurgical complications. A fiber-free, high-protein, and low-residue formula was started at 10 ml/h while the patient was receiving stable doses of midodrine, norepinephrine, and vasopressin. Despite advancement of tube-feed rates to goal, nasogastric output never exceeded 300 ml. Computerized tomography of the abdomen showed diffuse bowel distention with pneumatosis, concerning for bowel ischemia. No surgical interventions were pursued, and the patient died.

CONCLUSIONS

Our patient developed NOMI postoperatively while receiving EN. Further studies addressing EN route, trophic vs full EN, recommended formula, the safety of vasoactive agents, the addition of fiber to EN, and continuous venovenous hemodiafiltration in relation to NOMI are needed, as there continues to be clinical controversy regarding these topics.

Stress Hyperglycemia and Osteocalcin in COVID-19 Critically Ill Patients on Artificial Nutrition

We aimed to study the possible association of stress hyperglycemia in COVID-19 critically ill patients with prognosis, artificial nutrition, circulating osteocalcin, and other serum markers of inflammation and compare them with non-COVID-19 patients. Fifty-two critical patients at the intensive care unit (ICU), 26 with COVID-19 and 26 non-COVID-19, were included. Glycemic control, delivery of artificial nutrition, serum osteocalcin, total and ICU stays, and mortality were recorded. Patients with COVID-19 had higher ICU stays, were on artificial nutrition for longer (p = 0.004), and needed more frequently insulin infusion therapy (p = 0.022) to control stress hyperglycemia. The need for insulin infusion therapy was associated with higher energy (p = 0.001) and glucose delivered through artificial nutrition (p = 0.040). Those patients with stress hyperglycemia showed higher ICU stays (23 ± 17 vs. 11 ± 13 days, p = 0.007). Serum osteocalcin was a good marker for hyperglycemia, as it inversely correlated with glycemia at admission in the ICU (r = -0.476, p = 0.001) and at days 2 (r = -0.409, p = 0.007) and 3 (r = -0.351, p = 0.049). In conclusion, hyperglycemia in critically ill COVID-19 patients was associated with longer ICU stays. Low circulating osteocalcin was a good marker for stress hyperglycemia.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members.As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

Nutrition in the Intensive Care Unit-A Narrative Review

Background: While consent exists, that nutritional status has prognostic impact in the critically ill, the optimal feeding strategy has been a matter of debate. Methods: Narrative review of the recent evidence and international guideline recommendations focusing on basic principles of nutrition in the ICU and the treatment of specific patient groups. Covered topics are: the importance and diagnosis of malnutrition in the ICU, the optimal timing and route of nutrition, energy and protein requirements, the supplementation of specific nutrients, as well as monitoring and complications of a Medical Nutrition Therapy (MNT). Furthermore, this review summarizes the available evidence to optimize the MNT of patients grouped by primarily affected organ system. Results: Due to the considerable heterogeneity of the critically ill, MNT should be carefully adapted to the individual patient with special focus on phase of critical illness, metabolic tolerance, leading symptoms, and comorbidities. Conclusion: MNT in the ICU is complex and requiring an interdisciplinary approach and frequent reevaluation. The impact of personalized and disease-specific MNT on patient-centered clinical outcomes remains to be elucidated.

The correlation between gastric residual volumes and markers of gastric emptying: a post-hoc analysis of a randomized clinical trial

BACKGROUND

The correlation between gastric residual volumes (GRV) and markers of gastric emptying (GE) in critically ill patients is unclear. This is especially true for ICU surgical patients as they are underrepresented in previous studies.

METHODS

We conducted a post-hoc analysis of a multicenter trial that investigated the effectiveness of a promotility drug in increasing enteral nutrition intake. Pharmacokinetic markers of GE [3-O-methylglucose (3-OMG) and acetaminophen] were correlated with GRV measurements. High-GRV was defined as one episode of >400 mL or two consecutive episodes of >250 mL, and delayed GE was defined as <20^th percentile of the pharmacokinetic GE marker that had the strongest correlation with GE.

RESULTS

Out of 77 patients, 8 (10.4%) had high-GRV, and 15 (19.5%) had delayed GE. 3-OMG concentration at 60 mins had the strongest correlation with GRV (Rho: - 0.631), and high-GRV had low sensitivity (46.7%) but high specificity (98.4%) in discriminating delayed GE. The positive (87.5%) and negative (88.4%) predictive values were similar. There was a small sample of surgical patients (n = 14, 18.2%), and they had a significantly higher incidence of high-GRV (29% vs 6%, P: 0.032) and a trend towards delayed GE (36% vs 16%, p: 0.132) when compared to medical patients.

CONCLUSION

GRV reflects GE, and high-GRV is an acceptable surrogate marker of delayed GE. Based on our preliminary observation, surgical patients may have a higher risk of high-GRV and delayed GE. In summary, GRV should be monitored to determine if complex investigations or therapeutic interventions are warranted. This article is protected by copyright. All rights reserved.

Synbiotic Therapy Prevents Nosocomial Infection in Critically Ill Adult Patients: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials Based on a Bayesian Framework

Background: The efficacy of synbiotics, probiotics, prebiotics, enteral nutrition or adjuvant peripheral parenteral nutrition (EPN) and total parenteral nutrition (TPN) in preventing nosocomial infection (NI) in critically ill adults has been questioned. We conducted a systematic review and network meta-analysis (NMA) of randomized controlled trials (RCTs) to evaluate and rank the effectiveness of these therapies on NI amongst critically ill adults.

Methods: Four electronic databases were systematically searched up to June 30, 2019 for RCTs comparing the administration of probiotics, prebiotics, synbiotics, EPN and TPN in critically ill adults. The primary outcome was NI. The relative efficacy of all outcomes was determined by a Bayesian framework with random effects NMA. We estimated the odds ratio (OR) and mean difference (MD) and ranked the comparative effects of all regimens with the surface under the cumulative ranking probabilities. The study has been registered on PROSPERO (CRD42019147032).

Results: Fifty-five RCTs (7,119 patients) were identified. Primary outcome showed that synbiotics had the best effect in preventing NI than EPN (OR 0.37; 95% CrI 0.22–0.61), probiotics followed (OR 0.52; 95% CrI 0.34–0.77), whereas TPN significantly increased NI (OR 2.29; 95% CrI 1.48–3.67). Subgroup analysis showed that TPN significantly increased NI in intensive care unit (ICU) patients (OR 1.57; 95% CrI 1.01–2.56) and severe acute pancreatitis (SAP) patients (OR 3.93; 95% CrI 1.74–9.15). Secondary outcomes showed that synbiotics were more effective in preventing hospital-acquired pneumonia (HAP) (OR 0.34; 95% CrI 0.11–0.85), catheter-related bloodstream infection (OR 0.08; 95% CrI 0.01–0.80), urinary tract infection (OR 0.27; 95% CrI 0.08–0.71) and sepsis (OR 0.34; 95% CrI 0.16–0.70) than EPN. Amongst the treatments, probiotics were most effective for shortening the mechanical ventilation duration (MD −3.93; 95% CrI −7.98 to −0.02), prebiotics were most effective for preventing diarrhea (OR 0.24; 95% CrI 0.05–0.94) and TPN was the least effective in shortening hospital length of stay (MD 4.23; 95% CrI 0.97–7.33).

Conclusions: Amongst the five therapies, synbiotics not only prevented NI in critically ill adults but also demonstrated the best treatment results. By contrast, TPN did not prevent NI and ranked last, especially in ICU and SAP patients.

Take-Home Message: Nosocomial infection is a leading cause of mortality in critically ill patients in the ICU. However, the efficacy of synbiotics, probiotics, prebiotics, enteral nutrition or adjuvant peripheral parenteral nutrition and total parenteral nutrition in preventing nosocomial infection in critically ill adults has been questioned. The network meta-analysis provides evidence that amongst the five therapies, synbiotics not only prevented NI in critically ill adults but also demonstrated the best treatment results. By contrast, TPN did not prevent NI and ranked last, especially in ICU and SAP patients. The results of this study will provide a new scientific basis and a new idea for the debate on the efficacy of synbiotics and other treatments in the improvement of prognosis in critically ill adult patients.

Tweet: Synbiotic prevents nosocomial infection in critically ill adults, while total parenteral nutrition has the adverse curative.

A Bayesian analysis of mortality outcomes in multicentre clinical trials in critical care

BACKGROUND

Multicentre RCTs are widely used by critical care researchers to answer important clinical questions. However, few trials evaluating mortality outcomes report statistically significant results. We hypothesised that the low proportion of trials reporting statistically significant differences for mortality outcomes is plausibly explained by lower-than-expected effect sizes combined with a low proportion of participants who could realistically benefit from studied interventions.

METHODS

We reviewed multicentre trials in critical care published over a 10-yr period in the New England Journal of Medicine, the Journal of the American Medical Association, and the Lancet. To test our hypothesis, we analysed the results using a Bayesian model to investigate the relationship between the proportion of effective interventions and the proportion of statistically significant results for prior distributions of effect size and trial participant susceptibility.

RESULTS

Five of 54 trials (9.3%) reported a significant difference in mortality between the control and the intervention groups. The median expected and observed differences in absolute mortality were 8.0% and 2.0%, respectively. Our modelling shows that, across trials, a lower-than-expected effect size combined with a low proportion of potentially susceptible participants is consistent with the observed proportion of trials reporting significant differences even when most interventions are effective.

CONCLUSIONS

When designing clinical trials, researchers most likely overestimate true population effect sizes for critical care interventions. Bayesian modelling demonstrates that that it is not necessarily the case that most studied interventions lack efficacy. In fact, it is plausible that many studied interventions have clinically important effects that are missed.

Non-occlusive mesenteric ischemia: Diagnostic challenges and perspectives in the era of artificial intelligence

Acute mesenteric ischemia (AMI) is a severe condition associated with poor prognosis, ultimately leading to death due to multiorgan failure. Several mechanisms may lead to AMI, and non-occlusive mesenteric ischemia (NOMI) represents a particular form of AMI. NOMI is prevalent in intensive care units in critically ill patients. In NOMI management, promptness and accuracy of diagnosis are paramount to achieve decisive treatment, but the last decades have been marked by failure to improve NOMI prognosis, due to lack of tools to detect this condition. While real-life diagnostic management relies on a combination of physical examination, several biomarkers, imaging, and endoscopy to detect the possibility of several grades of NOMI, research studies only focus on a few elements at a time. In the era of artificial intelligence (AI), which can aggregate thousands of variables in complex longitudinal models, the prospect of achieving accurate diagnosis through machine-learning-based algorithms may be sought. In the following work, we bring you a state-of-the-art literature review regarding NOMI, its presentation, its mechanics, and the pitfalls of routine work-up diagnostic exams including biomarkers, imaging, and endoscopy, we raise the perspectives of new biomarker exams, and finally we discuss what AI may add to the field, after summarizing what this technique encompasses.

Role of ketones, ketogenic diets and intermittent fasting in ICU

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.

Impact of early nutrition route in patients receiving extracorporeal membrane oxygenation: A retrospective cohort study

BACKGROUND

Early nutrition management in patients receiving extracorporeal membrane oxygenation (ECMO) remains controversial. Despite its potentially beneficial effect, enteral nutrition (EN) could be associated with gastrointestinal (GI) complications. Total daily energy requirements remain difficult to achieve with ECMO support. Analysis of nutrition practices could improve nutrition management of this particular population.

METHODS

A monocentric retrospective study of patients requiring ECMO in a cardiac surgery intensive care unit (ICU) between 2010 and 2014 with follow-up ≥6 days. Nutrition support was monitored daily until ECMO weaning. We compared patients exposed (EN group, n = 49) and unexposed (No EN group (NEN), n = 63) with EN, as well as the energy and protein intakes within 4 days after initiation of ECMO. Vital status and nosocomial infections were followed up until ICU discharge. Primary outcome was the incidence of GI intolerance and risk-factor identification. Secondary outcomes included impact of nutrition inadequacy and clinical outcome.

RESULTS

A total 112 patients were analyzed, representing 969 nutrition days. Median ratio of energy and protein prescribed/required daily was 81% (58-113) and 56% (36-86), respectively. GI intolerance was experienced by 53% (26 of 49) of patients in the EN group and was only associated with ECMO duration (odds ratio, 1.14: 95% CI, 1.00-1.31; P = .05). Low-energy and protein days were not associated with clinical outcomes such as nosocomial infections.

CONCLUSION

EN is associated with almost 50% GI intolerance without clinical benefit for patients receiving ECMO. Adequacy in energy and protein amounts did not affect clinical outcome.

The Influence of Timing in Critical Care Nutrition

Proper timing of critical care nutrition has long been a matter of controversy. Critical illness waxes and wanes in stages, creating a dynamic flux in energy needs that we have only begun to examine. Furthermore, response to nutrition support likely differs greatly at the level of the individual patient in regard to genetic status, disease stage, comorbidities, and more. We review the observational and randomized literature concerning timing in nutrition support, discuss mechanisms of harm in feeding critically ill patients, and highlight the role of precision nutrition for moving the literature beyond the realm of blunt population averages into one that accounts for the patient-specific complexities of critical illness and host genetics. Expected final online publication date for the Annual Review of Nutrition, Volume 41 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Impact of early low-calorie low-protein versus standard-calorie standard-protein feeding on outcomes of ventilated adults with shock: design and conduct of a randomised, controlled, multicentre, open-label, parallel-group trial (NUTRIREA-3)

INTRODUCTION

International guidelines include early nutritional support (≤48 hour after admission), 20-25 kcal/kg/day, and 1.2-2 g/kg/day protein at the acute phase of critical illness. Recent data challenge the appropriateness of providing standard amounts of calories and protein during acute critical illness. Restricting calorie and protein intakes seemed beneficial, suggesting a role for metabolic pathways such as autophagy, a potential key mechanism in safeguarding cellular integrity, notably in the muscle, during critical illness. However, the optimal calorie and protein supply at the acute phase of severe critical illness remains unknown. NUTRIREA-3 will be the first trial to compare standard calorie and protein feeding complying with guidelines to low-calorie low-protein feeding. We hypothesised that nutritional support with calorie and protein restriction during acute critical illness decreased day 90 mortality and/or dependency on intensive care unit (ICU) management in mechanically ventilated patients receiving vasoactive amine therapy for shock, compared with standard calorie and protein targets.

METHODS AND ANALYSIS

NUTRIREA-3 is a randomised, controlled, multicentre, open-label trial comparing two parallel groups of patients receiving invasive mechanical ventilation and vasoactive amine therapy for shock and given early nutritional support according to one of two strategies: early calorie-protein restriction (6 kcal/kg/day-0.2-0.4 g/kg/day) or standard calorie-protein targets (25 kcal/kg/day, 1.0-1.3 g/kg/day) at the acute phase defined as the first 7 days in the ICU. We will include 3044 patients in 61 French ICUs. Two primary end-points will be evaluated: day 90 mortality and time to ICU discharge readiness. The trial will be considered positive if significant between-group differences are found for one or both alternative primary endpoints. Secondary outcomes include hospital-acquired infections and nutritional, clinical and functional outcomes.

ETHICS AND DISSEMINATION

The NUTRIREA-3 study has been approved by the appropriate ethics committee. Patients are included after informed consent. Results will be submitted for publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03573739.

Infarction-Related Cardiogenic Shock- Diagnosis, Monitoring and Therapy

BACKGROUND

The second edition of the German-Austrian S3 guideline contains updated evidence-based recommendations for the treatment of patients with infarction-related cardiogenic shock (ICS), whose mortality is several times higher than that of patients with a hemodynamically stable myocardial infarction (1).

METHODS

In five consensus conferences, the experts developed 95 recommendations-including two statements-and seven algorithms with concrete instructions.

RESULTS

Recanalization of the coronary vessel whose occlusion led to the infarction is crucial for the survival of patients with ICS. The recommended method of choice is primary percutaneous coronary intervention (pPCI) with the implantation of a drug-eluting stent (DES). If multiple coronary vessels are diseased, only the infarct artery (the "culprit lesion") should be stented at first. For cardiovascular pharmacotherapy-primarily with dobutamine and norepinephrine-the recommended hemodynamic target range for mean arterial blood pressure is 65-75 mmHg, with a cardiac index (CI) above 2.2 L/min/m2. For optimal treatment in intensive care, recommendations are given regarding the type of ventilation (invasive rather than non-invasive, lungprotective), nutrition (no nutritional intake in uncontrolled shock, no glutamine supplementation), thromboembolism prophylaxis (intravenous heparin rather than subcutaneous prophylaxis), und further topics. In case of pump failure, an intra-aortic balloon pump is not recommended; temporary mechanical support systems (Impella pumps, veno-arterial extracorporeal membrane oxygenation [VA-ECMO], and others) are hemodynamically more effective, but have not yet been convincingly shown to improve survival.

CONCLUSION

Combined cardiological and intensive-care treatment is crucial for the survival of patients with ICS. Coronary treatment for ICS seems to have little potential for further improvement, while intensive-care methods can still be optimized.