ESPEN practical and partially revised guideline: Clinical nutrition in the intensive care unit

The Gut in Critical Illness

PURPOSE OF REVIEW

The purpose of this narrative review is to describe the mechanisms for gut dysfunction during critical illness, outline hypotheses of gut-derived inflammation, and identify nutrition and non-nutritional therapies that have direct and indirect effects on preserving both epithelial barrier function and gut microbiota during critical illness.

RECENT FINDINGS

Clinical and animal model studies have demonstrated that critical illness pathophysiology and interventions breach epithelial barrier function and convert a normally commensal gut microbiome into a pathobiome. As a result, the gut has been postulated to be the "motor" of critical illness and numerous hypotheses have been put forward to explain how it contributes to systemic inflammation and drives multiple organ failure. Strategies to ameliorate gut dysfunction have focused on maintaining gut barrier function and promoting gut microbiota commensalism. The trajectory of critical illness may be closely related to gut epithelial barrier function, the gut microbiome and interventions that may contribute towards a deleterious pathobiome with immune dysregulation.

Preferences on the Use of Prokinetic Agents in Adult Intensive Care Unit Patients-An International Survey

INTRODUCTION

Feeding intolerance complicates enteral nutrition in intensive care unit (ICU) patients but is poorly defined. Prokinetic agents are administered to facilitate the uptake of enteral nutrition, but preferences for their use among clinicians in ICUs are unknown.

METHODS

We conducted an international electronic survey targeting ICU doctors. The survey included 76 questions that focused on symptoms considered when assessing feeding intolerance, preferences for using prokinetic agents, and willingness to participate in a future randomised trial on prokinetic agents.

RESULTS

We received 830 responses from 17 countries, with an overall response rate of 29%. Most respondents were specialists working in mixed ICUs. Feeding intolerance was assessed by 90% of respondents in their clinical work, though only 36% considered it well defined. Gastric residual volume and vomiting were symptoms most frequently used for defining feeding intolerance. Metoclopramide was the preferred prokinetic agent (54% of respondents), followed by erythromycin (42%). Four out of five considered using combination therapy, primarily a combination of metoclopramide and erythromycin (89%). Concerns about side effects were reported for all agents, with extrapyramidal symptoms and QT prolongation being the most common across agents. The majority (91%) of respondents supported a future randomised trial comparing prokinetic agents to placebo.

CONCLUSION

This international survey found practice variations in the symptoms reportedly used to assess feeding intolerance. Metoclopramide was the preferred prokinetic agent, followed by erythromycin. Most respondents supported a future randomised trial.

Standard continuous feeding versus intermittent feeding among mechanically ventilated patients in intensive care: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Previous meta-analyses on the mode of enteral nutrition in intensive care unit (ICU) have not explored whether the standard practice of continuous enteral feeding is superior to intermittent or bolus feeding among mechanically ventilated patients. Large feed volumes maybe one of the barriers for the use of intermittent feeding. However, intermittent feeding when routinely paired with right lateral tilt positioning may be better tolerated. Aligning feeding-fasting periods with circadian patterns may also be beneficial during critical illness in relation to important patient-centered clinical outcomes.

OBJECTIVES

This systematic review and meta-analysis will summarize the current state of evidence from all randomized controlled trials (RCTs) comparing standard continuous gastric feeding and intermittent gastric feeding (with or without right lateral tilt positioning) among critically ill adult patients receiving mechanical ventilation in ICU.

METHODS

A systematic search was conducted in MEDLINE, EMBASE and CENTRAL for relevant RCTs published in the English language until September 2024. The primary outcome was all cause hospital mortality, expressed as pooled risk ratio (RR) for the standard continuous feeding relative to intermittent feeding. Key secondary outcomes were ICU length of stay, gut intolerance (vomiting and diarrhoea) and pneumonia.

RESULTS

Sixteen studies were identified for full text review out of a total of 678 records screened. Eight RCTs enrolling a total of 993 patients were included in this meta-analysis. There was a substantial heterogeneity in outcomes selection, definitions, and reporting among these RCTs. Aggregate effect size for the primary outcome was RR 0.97 (95 % confidence interval 0.72-1.32, I2 = 9 %) for standard continuous feeding versus intermittent feeding. There were no between-group differences for any of the other secondary outcomes. Of all the included RCTs, the point estimate for all-cause mortality was least favourable (RR 1.55, 95 % CI 0.82 to 2.93) for the standard continuous feeding in the RCT that compared it against intermittent postural feeding.

CONCLUSIONS

Overall, our meta-analysis did not detect any clinically relevant differences in important clinical outcomes between the two groups. Future RCTs should prioritise clinically meaningful, patient-centred outcomes such as mortality or ventilator-free days as primary endpoints.

PROSPERO REGISTRATION NUMBER

CRD42024591074.

Acute kidney injury in patients undergoing major surgery and clinical practice of intravenous amino acids: A descriptive study in Japan

BACKGROUND & AIMS

The use of aggressive perioperative intravenous amino acid administration to prevent postoperative acute kidney injury (AKI) has been examined. While it is crucial to understand the clinical course of postoperative AKI in order to develop a nutritional strategy, few studies have investigated real-world postoperative AKI after major surgeries and nutrition practices.

METHODS

We herein assessed the incidence of postoperative AKI and intravenous amino acid use in patients without renal dysfunction who were admitted to the intensive care unit after major surgery in an administrative claims database. Postoperative AKI within one week was evaluated according to the Kidney Disease: Improving Global Outcomes creatinine criteria.

RESULTS

In 30,751 patients analyzed, AKI occurred in 7.1 % (1.3 % were stage 2 or higher). Blood urea nitrogen levels had not returned to baseline two weeks after surgery, even in patients with stage 1 AKI. The incidence of delayed AKI (diagnosed 2-7 days after surgery) was higher in patients who underwent non-cardiovascular surgery (25.1 % for cardiovascular surgery and 37.2 % for non-cardiovascular surgery). Patients with delayed AKI had a significantly poorer prognosis than those diagnosed with AKI on day 1. Although the practice of intravenous amino acids varied across surgeries, few patients received aggressive doses, such as 2 g/kg/day. No significant differences were observed in the incidence of AKI between patients who received and did not receive an amino acid infusion on the day of surgery.

CONCLUSIONS

In real-world settings, perioperative aggressive amino acid administration was not a common practice, and renal protective effects may not be achieved with usual doses. Nutritional assessments with the daily monitoring of AKI stages may be warranted for the provision of nutrition therapy, including the protein load.

Macronutrient intake is different across Europe: Results of a Belgian cohort of critically ill adults

BACKGROUND & AIMS

Medical nutrition therapy (MNT) is fundamental for ICU patients. This post-hoc subgroup analysis of the prospective observational EuroPN survey aimed to assess MNT in the participating Belgian ICUs.

METHODS

MNT practices in 9 Belgian ICUs (148 patients) were compared to 77 ICUs (1172 patients) from 11 European countries during the first 15 days for patients staying ≥5 days in ICU - and with the 2019 ESPEN guideline on clinical nutrition in ICU (<70 % of estimated energy expenditure in week 1 and up to 1.3 g/kg/d protein). Additionally, overfeeding was evaluated in the Belgian cohort.

RESULTS

The Belgian cohort had longer median ICU and hospital length of stay, higher emergency room admission rates and delayed MNT initiation compared to overall (EN: day 2.5 [2.0;4.0] vs 2.0 [2.0;4.0] and PN: day 5.0 [3.0,7.0] vs 2.0 [2.0,4.0]). They received more often EN than PN. In week 1 overfeeding was on average present in 30 % (energy) and 15 % (protein) of observation days.

CONCLUSION

Similar to overall, the Belgian subgroup received a daily average moderate caloric and low protein intake. The gradual intake increase aligned with ESPEN guidelines, though temporary overfeeding occurred in about one third of the patients.

Understanding Refeeding Syndrome in Critically Ill Patients: A Narrative Review

Refeeding syndrome (RS) is defined as the spectrum of metabolic and biochemical disorders related to rapid nutritional replenishment after a prolonged period of fasting. It is caused by an abrupt shift in electrolytes and fluid among intra- and extracellular compartments, leading to metabolic disturbances like hypophosphatemia, vitamin deficiency, and fluid overload. RS often remains underdiagnosed due to variability in definition and diagnostic criteria adopted, overlapping clinical features with other complications and low awareness among clinicians. Critically ill individuals, particularly those admitted to intensive care units (ICUs), represent a cohort with peculiar features that may heighten RS risk due to their baseline frailty, frequent undernutrition, and the metabolic stress of acute illness. However, studies specifically conducted in ICU settings have yielded conflicting results regarding incidence rates, prognostic impact, and specific risk factors. Despite these differences, all evidence consistently highlights RS as a frequent and serious complication in critically ill patients. Early detection and prevention are essential, relying on prompt nutritional assessment at ICU admission, careful monitoring of serum electrolytes before and during refeeding, and a conservative caloric approach to nutrient reintroduction, alongside supportive therapy and electrolyte supplementation if RS manifestations occur. Clinicians should be aware of the significant prevalence and potential severity of RS in critically ill patients, along with the ongoing challenges related to its early recognition, prevention, and optimal nutritional management. This review aims to provide a comprehensive overview of the current knowledge on the incidence, prognostic impact, risk factors, clinical manifestations, and nutritional management of RS in critically ill patients while highlighting existing evidence gaps and key areas requiring clinical attention.

REDuced CARBohydrate enteral nutrition compared to standard care in hyperglycaemic critically ill patients: A randomised phase II clinical trial (REDCARB)

BACKGROUND

Critically ill patients often experience dysglycaemia which is strongly associated with increased morbidity and mortality. While exogenous insulin therapy is used to manage hyperglycaemia, it has been demonstrated to increase the frequency of hypoglycaemic episodes and variability in blood glucose, both of which have been shown to increase mortality. Enteral feeding may worsen glycaemic control due to its carbohydrate content. This study aims to determine if the use of a reduced carbohydrate formula improves overall glycaemic control when compared to standard care in critically ill patients with hyperglycaemia.

METHODS

This is the protocol for a multicentre, prospective randomised controlled trial conducted at 7 intensive care units (ICU). One hundred and sixty patients admitted to ICU, receiving or about to receive enteral nutrition expected to continue until the day after tomorrow, who have had two consecutive blood glucose levels >10 mmol/L or have received insulin based on local protocols within the previous 24-h period, and who meet none of the exclusion criteria, will be eligible. Patients in the standard care arm will receive enteral nutrition as per usual site practice and patients in the intervention arm will receive Glucerna Select® to achieve a caloric equivalent to that prescribed or delivered prior to study recruitment. All other aspects of nutrition management remain as per routine clinical practice. The primary outcome measure is units of insulin administered per day in the ICU to a maximum of seven days post randomisation. Key secondary outcome measures include measures of glycaemic control, nutrition provision, nutrition tolerance and clinical outcomes such as infectious complications, duration of ventilation, ICU and hospital stay as well as in hospital mortality.

DISCUSSION

This study will provide data on whether the use of a reduced carbohydrate enteral nutrition formula reduces insulin administration thereby improving dysglycaemia in critically ill patients. It will also be used to refine the design of a larger multi-centre trial to definitively ascertain the impact of using reduced carbohydrate enteral formula on clinical outcomes.

ETHICS AND TRIAL REGISTRATION

Ethical approval was obtained from the local Research Ethics Committee (HREC Approval HREC/2021/QMS/74667). The trial was registered on the Clinical Trials Registry with registration number ACTRN12621000859886.

Contemporary Rationale for Delivering Enteral Nutrition in Critically Ill Adults

OBJECTIVES

To review the rationale for and timing, dose, and monitoring of enteral nutrition and protein delivery in critically ill adults.

DATA SOURCES

Medline searches to identify relevant studies, systematic reviews and meta-analyses, and guidelines informing the phases of critical illness, enteral nutrition and protein doses, and monitoring enteral nutrition.

STUDY SELECTION

Preclinical and contemporary clinical literature informing the rationale for and timing, dose, and monitoring of enteral nutrition and protein dose in critically ill adults.

DATA EXTRACTION

The evidence describing the rationale for and timing, dose, and monitoring of enteral nutrition and protein dose in critically ill adults is summarized.

DATA SYNTHESIS

The early delivery of enteral nutrition remains a cornerstone of therapy for critically ill adults. Historically, critical care nutrition guidelines have recommended achieving full-dose enteral nutrition within the first 72 hours of ICU admission. The rationale for delivering early enteral nutrition depends on the phase of critical illness, and providing a restrictive dose during the acute phase preserves gut integrity, supports the microbiome, and modulates immune dysregulation. Contemporary randomized controlled trials comparing enteral nutrition doses during the acute phase of critical illness have found full-dose enteral nutrition, compared with restrictive dose, and may offset the benefit from enteral feeding, causing iatrogenic stresses to the system leading to worse outcomes. Even though critically ill adults have anabolic resistance and undergo skeletal muscle proteolysis, recent trials have found that high-dose protein, compared with standard, does not improve clinical outcomes and may be harmful in certain subsets of critically ill adults.

CONCLUSIONS

Contemporary data support the use of restrictive dose enteral nutrition during the acute phase of critical illness. High-dose protein is not superior to lower and is associated with worse outcomes in critically ill adults with acute kidney injury and those with greater severity of illness.

A New Perspective on Overfeeding in the Intensive Care Unit (ICU): Challenges, Dangers and Prevention Methods

Overfeeding, currently defined as providing excessive energy and nutrients beyond metabolic requirements, is a common yet often overlooked issue in the intensive care unit (ICU) setting. Understanding the factors contributing to overfeeding and implementing strategies to prevent it is essential for optimizing patient care in the ICU. Several factors contribute to overfeeding in the ICU, including inaccurate estimation of energy requirements, formulaic feeding protocols, and failure to adjust nutritional support based on individual patient needs. Prolonged overfeeding can lead to insulin resistance and hepatic dysfunction, exacerbating glycemic control, increasing the risk of infectious complications, and worsening clinical outcomes. Clinically, overfeeding has been linked to delayed weaning from mechanical ventilation, prolonged ICU stay, and increased mortality rates. Regular review and adjustment of feeding protocols, incorporating advances in enteral and parenteral nutrition strategies, are essential for improving patient outcomes. Clinicians must be proficient in interpreting metabolic data, understanding the principles of energy balance, and implementing appropriate feeding algorithms. Interdisciplinary collaboration among critical care teams, including dieticians, physicians, and nurses, is crucial for ensuring consistent and effective nutritional management. Overfeeding remains a significant concern in the ICU after discharge as well, implying further complications for patient safety and integrity. By understanding the causes, consequences, and strategies for the prevention of overfeeding, healthcare providers can optimize nutrition therapy and mitigate the risk of metabolic complications. Through ongoing education, interdisciplinary collaboration, and evidence-based practice, the ICU community can strive to deliver personalized and precise nutritional support to critically ill patients.

Significant Published Articles in 2024 for Pharmacy Nutrition Support Practice

Purpose: The purpose of this article is to assist the pharmacist engaged in nutrition support therapy in staying current with pertinent literature. Methods: Several board-certified nutrition support pharmacists aggregated a list of articles relevant to pharmacy nutrition support that was published in 2024. The list was compiled into a spreadsheet whereby the authors were asked to assess whether the article was considered important. A culled list of publications was then identified whereby at least 5 out of the 8 author participants considered the article to be important for pharmacists practicing in nutrition support. Guideline and consensus papers, important to practice but not ranked, were also included. Results: A total of 160 articles were identified; 7 from the primary literature were voted by the group as being of high importance. Twelve guidelines, position, recommendation, or consensus papers were also identified. The top-ranked articles from the primary literature were summarized and a narrative regarding its implications to pharmacy nutrition support practice were provided. Conclusion: We recommend that pharmacists engaged in nutrition support therapy be familiar with these articles as they pertain to their practice.

Association of modified NUTRIC score for nutritional risk and in-hospital developed malnutrition in adults with severe injuries: a prospective observational cohort study

BACKGROUND

This study investigated the prevalence of high nutritional risk (modified Nutrition Risk in Critically Ill (mNUTRIC) score ≥ 5) and its relation with malnutrition and other adverse in-hospital outcomes in severely injured patients (Injury Severity Score ≥ 16), admitted to the ICU. We hypothesized that high nutritional risk is associated with an increased risk of developing malnutrition (primary hypothesis) and of complications and mortality (secondary hypotheses) in adults with severe injuries compared to those with low nutrition risk.

METHODS

In this observational prospective study, 100 severely injured patients admitted to the ICU of five Level-1 trauma centers in the US and the Netherlands between 2018-2022 were included. During ICU and hospital stay, malnutrition rates (Subjective Global Assessment score ≤ 5), complication rates (systemic complications, pneumonia, urinary tract infection, venous thromboembolism), and mortality of severely injured patients with high versus low nutritional risk were compared. A cause-specific Cox regression model was fitted to analyze whether high nutritional risk was related to developing malnutrition.

RESULTS

Eighteen percent of patients had high nutritional risk (95% confidence interval [CI] 10.5-25.5%) at admission. High nutritional risk was not related to in-ICU or in-hospital developed malnutrition. In patients with high nutritional risk, the hazard ratio for developing malnutrition was 1.3 (95% CI 0.7-2.6, p = 0.45). Severely injured patients with high nutritional risk had more complications during ICU (78% vs 29%, p < 0.001; OR 8.5, 95% CI 2.5-28.3) and hospital stay (83% vs 41%, p < 0.01; OR 6.0, 95% CI 1.5-24.9). ICU mortality (22% vs 4%, p = 0.02; OR 7.5, 95% CI 1.5-37.3) and hospital mortality (33% vs 6%, p < 0.01; OR 5.9, 95% CI 1.3-26.4) were also higher in patients with high nutritional risk.

CONCLUSION

About one-fifth of severely injured patients admitted to the ICU had high nutritional risk. High nutritional risk in severely injured patients is not associated with malnutrition. It is potentially associated with adverse in-hospital outcomes.

LEVEL OF EVIDENCE

Level III, Prognostic/Epidemiological.

Elevated albumin: a protective factor against mortality in geriatric hip fracture patients

INTRODUCTION

To evaluate the association between albumin concentration at admission and mortality in elderly patients with hip fractures.

METHODS

Elderly patients with hip fractures were screened between Jan 2015 and Sep 2019. Demographic and clinical characteristics of the patients were collected. Linear and nonlinear multivariate Cox regression models were used to identify the association between albumin concentration at admission and mortality. All analyses were performed using EmpowerStats and the R software.

RESULTS

This retrospective cohort study included 2387 patients who met the study criteria. The mean follow-up was 37.64 months. The albumin concentration was 37.72 ± 4.03 g/L. Multivariate Cox regression showed that albumin concentration was associated with mortality in geriatric patients with hip fracture (Hazard Ratio [HR] = 0.94, 95% confidence intervals [CI]:0.92-0.96, P < 0.0001). Compared to the low albumin group (< 35 g/L), the medium group (≥ 35 g/L and < 40 g/L) decreased mortality risk by 29% (HR = 0.71, 95%CI:0.59-0.86, P = 0.0003), and the high group (≥ 40 g/L) decreased mortality risk by 38% (HR = 0.62, 95%CI:0.49-0.79, P < 0.0001). In addition, the test for a linear trend (P for trend) also showed a linear correlation in the different models. No saturation or threshold effect was observed in the nonlinear association. The sensitivity analysis used propensity score matching, and the results were stable.

CONCLUSION

The albumin concentrations at admission were associated with mortality in geriatric hip fractures, and it could be considered a predictor for the risk of mortality. (ChiCTR2200057323).

Technology advances in the placement of naso-enteral tubes and in the management of enteral feeding in critically ill patients: A narrative study

Enteral feeding needs secure access to the upper gastrointestinal tract, an evaluation of the gastric function to detect gastrointestinal intolerance, and a nutritional target to reach the patient's needs. Only in the last decades has progress been accomplished in techniques allowing an appropriate placement of the nasogastric tube, mainly reducing pulmonary complications. These techniques include point-of-care ultrasound (POCUS), electromagnetic sensors, real-time video-assisted placement, impedance sensors, and virtual reality. Again, POCUS is the most accessible tool available to evaluate gastric emptying, with antrum echo density measurement. Automatic measurements of gastric antrum content supported by deep learning algorithms and electric impedance provide gastric volume. Intragastric balloons can evaluate motility. Finally, advanced technologies have been tested to improve nutritional intake: Stimulation of the esophagus mucosa inducing contraction mimicking a contraction wave that may improve enteral nutrition efficacy, impedance sensors to detect gastric reflux and modulate the rate of feeding accordingly have been clinically evaluated. Use of electronic health records integrating nutritional needs, target, and administration is recommended.

The 30-min diaphragm movement change rate for predicting weaning success in severe pneumonia patients requiring invasive ventilation

Purpose

This study evaluated the 30-min diaphragm excursion change rate (ΔDE30-0) as a novel predictor of weaning success compared to existing parameters in patients with severe pneumonia requiring invasive mechanical ventilation.

Methods

This retrospective cohort study enrolled patients with severe pneumonia requiring invasive mechanical ventilation (n = 100). The patients were divided into successful (n = 79) and failed (n = 21) extubation groups. Ultrasound measurements of diaphragm excursion (DE) were performed at baseline (DE0) and 30 min (DE30) during a spontaneous breathing trial. The ratio ΔDE30-0 was calculated as the absolute difference between DE30 and DE0 divided by DE0. Additional parameters including rapid shallow breathing index (Rapid Shallow Breathing Index, RSBI) and respiratory rate (RR) were also assessed. The predictive performance of ΔDE30-0 and other parameters was evaluated using receiver operating characteristic (ROC) curves.

Results

The extubation failure group had significantly higher ΔDE30-0 (0.40 ± 0.20 vs. 0.14 ± 0.12, p < 0.0001), RSBI (59.62 ± 21.77 vs. 47.7 ± 13.6, p = 0.0025), and RR (23.62 ± 2.25 vs. 20.34 ± 2.18, p < 0.0001) compared to the success group. ΔDE30-0 demonstrated the highest predictive performance with an area under the ROC curve of 0.924, sensitivity of 86.1%, and specificity of 95.2% at a cut-off value of 0.209.

Conclusions

ΔDE30-0 is a promising predictor of weaning success in severe pneumonia patients requiring invasive mechanical ventilation. It outperformed existing parameters and demonstrated high predictive accuracy.

Implications for clinical practice

Incorporating ΔDE30-0 into weaning protocols may improve decision-making, reduce complications, and optimize outcomes for patients requiring invasive mechanical ventilation due to severe pneumonia. This novel parameter can aid clinicians in identifying suitable candidates for extubation, potentially reducing the risk of weaning failure and associated adverse events.

Personalized Nutrition Strategies for Patients in the Intensive Care Unit: A Narrative Review on the Future of Critical Care Nutrition

Introduction: Critically ill patients in intensive care units (ICUs) are at high risk of malnutrition, which can result in muscle atrophy, polyneuropathy, increased mortality, or prolonged hospitalizations with complications and higher costs during the recovery period. They often develop ICU-acquired weakness, exacerbated by sepsis, immobilization, and drug treatments, leading to rapid muscle mass loss and long-term complications. Studies indicate that adequate protein and calorie intake can decrease mortality and improve prognosis and recovery. However, optimal implementation remains a critical challenge. Objectives: This narrative review aims to summarize recent advances in nutritional strategies for critically ill patients. It highlights the benefits and limitations of current approaches including enteral (EN) and parenteral nutrition (PN) and examines their impact on clinical outcomes and overall mortality. Additionally, the review explores the emerging role of precision nutrition in critical care using technologies such as metabolomics and artificial intelligence (AI) to provide valuable insights into optimizing nutritional care in critically ill patients. Methods: A comprehensive literature search was conducted to identify recent studies, clinical guidelines, and expert consensus papers on nutritional support for ICU patients. The investigation focused on critical aspects such as the optimal timing for intervention, the route of administration, specific protein and energy targets, and technological innovations to support personalized nutrition, ensuring that each patient receives tailored support based on their unique needs. Results: Guidelines recommend initiating EN or PN nutrition within the first 48 h of admission, using indirect calorimetry (IC) to estimate energy needs, and supplementing protein up to 1.2 g/kg/day after stabilization. IC has gained importance in assessing energy needs but is still underused in the ICU. EN is preferred because it maintains intestinal integrity, reduces the risk of infections, and is recommended within the first 48 h of ICU admission. PN is used when EN is infeasible, but it increases the risk of infection. By integrating metabolomics with transcriptomic and genomic data, we can gain a deeper understanding of the effect of nutrition on cellular homeostasis, facilitating personalized treatments and enhancing the recovery of critically ill patients. Conclusions: AI is becoming increasingly important in monitoring and evaluating artificial nutrition, providing a more accurate and efficient alternative to traditional methods. AI can assist in identifying and managing malnutrition and is effective for estimating caloric and nutrient intake. AI minimizes human error, enables continuous monitoring, and integrates various data sources. The nutritional care of critically ill patients requires collaboration among specialists from diverse fields, including physicians, nutritionists, pharmacists, radiologists, IT experts, and policymakers.

Protective nutrition strategy in the acute phase of critical illness: why, what and how to protect

Nutritional support is crucial for critically ill patients. Recent clinical studies suggest that both overfeeding during the acute phase of critical illness and overly conservative or delayed nutritional therapy can pose significant risks. Given substantial individual variability among critically ill patients, it is challenging to prescribe universally applicable and objective feeding strategies; Instead, we pointed out which nutritional interventions were harmful. We also summarized the reasons for protective nutrition, and elaborated the advantages of protective nutrition from three perspectives: gastrointestinal protection, nutritional protection and metabolic protection. In particular, it is emphasized that overfeeding will lead to metabolic disorders, such as mitochondrial dysfunction, autophagy inhibition, ketogenic inhibition, hyperglycemia, insulin resistance, etc. These detrimental processes can exacerbate one another, contributing to multiple organ dysfunction syndrome and poorer clinical outcomes. We also propose protective nutrition strategies comparable to lung protective ventilation strategies, which may benefit patients. Vigilant monitoring during nutritional implementation is also paramount, enhancing awareness of adverse events for early diagnosis and intervention to mitigate their harm.

Low, Intermediate, and High Glutamine Levels Are Progressively Associated with Increased Lymphopenia, a Diminished Inflammatory Response, and Higher Mortality in Internal Medicine Patients with Sepsis

Background: The pathophysiological mechanisms underlying altered plasma glutamine concentrations in sepsis remain poorly understood. Identifying clinical, immunological, and metabolic correlates of glutamine fluctuations is crucial to advancing precision medicine, developing targeted therapies, and improving survival outcomes in septic patients. Methods: We enrolled 469 patients with sepsis and assessed inflammatory markers-including body temperature, white blood cell count, and C-reactive protein levels-upon admission to the internal medicine unit. Lymphocyte count and plasma concentrations of glutamine, glutamic acid, 5-oxoproline, phenylalanine, tyrosine, and leucine were measured using gas chromatography-mass spectrometry. Patients were stratified into three groups based on plasma glutamine levels. Mortality was recorded at 30 days and 6 months. Results: Low, intermediate, and high glutamine levels were observed in 46% (n = 217), 47% (n = 218), and 7% (n = 34) of patients, respectively. Patients with hyperglutaminemia exhibited significantly lower body temperature, white blood cell and lymphocyte counts, C-reactive protein levels, and glutamic acid-to-5-oxoproline ratio (a surrogate marker of glutathione availability), along with elevated phenylalanine levels, leucine levels, and tyrosine-to-phenylalanine ratio (all p < 0.01). Metabolic disruption and mortality increased progressively across glutamine level groups. Kaplan-Meier analysis demonstrated significantly higher mortality in patients with elevated glutamine levels at both 30 days (log-rank p = 0.03) and 6 months (log-rank p = 0.05). Conclusions: At baseline, increasing plasma glutamine levels are associated with progressively deeper lymphopenia, more pronounced metabolic derangement, and higher short- and long-term mortality in patients with sepsis.

Construction and Validation of a Risk Prediction Model for Acute Gastrointestinal Injury in Non-ICU Elderly Critically Ill Patients

BACKGROUND

Acute gastrointestinal injury (AGI) has a relatively high prevalence among elderly critically ill patients in non-intensive care units (non-ICUs), and significantly influences their clinical outcomes. Therefore, it is important to identify people at risk for AGI and take preventive measures as early as possible.

OBJECTIVE

We aimed to construct and validate a risk prediction model for AGI in non-ICU elderly critically ill patients.

DESIGN

Case-control study.

PARTICIPANTS

In total, 538 elderly critically ill patients admitted to the general medical department of a tertiary hospital in Shanxi from April 2021 to May 2024.

MAIN MEASURES

Influential factors for AGI were determined using univariate and multifactorial logistic regression analyses. We constructed a risk prediction model and created a nomogram. The bootstrap resampling method was utilized for internal validation. A total of 151 patients from different time periods were selected for the external validation.

KEY RESULTS

The multifactorial logistic regression analysis revealed that the independent predictors for AGI were the duration of antibiotic use, number of vasoactive drugs, delayed enteral nutrition, age-corrected Charlson comorbidity index, and white blood cell count, all of which were included in the model and created a nomogram. The Omnibus test showed that the overall efficacy of the model was good (P < 0.001). The area under the receiver operating characteristic curve (AUC) was 0.807, the corrected AUC was 0.806, and the AUC was 0.796 for external validation, indicating good model discrimination. The calibration curves and Hosmer-Lemeshow tests revealed that the model was well calibrated (P = 0.627, Brier = 0.172 in internal validation; and P = 0.366, Brier = 0.182 in external validation). The clinical decision curves showed that the model had good clinical utility.

CONCLUSIONS

AGI is common in non-ICU elderly critically ill patients. This AGI risk prediction model can be used as a screening tool to identify high-risk patients for AGI and assist clinical decision making.

Effects of probiotic supplementation on infectious and gastrointestinal complications of critically ill patients: Randomized, blinded, placebo-controlled clinical trial

BACKGROUND

Critically ill patients frequently experience alterations in gut microbiota, known as dysbiosis, which has been associated with unfavorable clinical outcomes. The use of probiotics is one approach to modulating gut microbiota.

OBJECTIVE

This study aimed to evaluate the effects of probiotic supplementation combined with enteral nutrition (EN) in critically ill patients on infectious, gastrointestinal complications, and clinical outcomes.

METHODS

This is a randomized, blinded, placebo-controlled clinical trial conducted with 70 individuals aged ≥18 years, receiving enteral nutrition, and admitted to the emergency intensive care unit (ICU) of a tertiary hospital. The intervention consisted of Lactobacillus paracasei SD 5275, Lactobacillus rhamnosus SD 5675, Lactobacillus acidophilus SD 5221, and Bifidobacterium lactis SD 5674 (109 Colony Forming Units (CFU) of each bacterium/sachet, two sachets per day were used), administered via EN once daily for at least 5 days until ICU discharge, death, or initiation of an oral diet. The primary outcomes were the occurrence of infections and gastrointestinal symptoms. Secondary outcomes included the use of antibiotics, laxatives, prokinetics, duration of mechanical ventilation (MV), ICU stay, and mortality.

RESULTS

There was no significant difference in the occurrence of any type of infection or gastrointestinal symptoms between the groups (p ≥ 0.05). The use of antibiotics and laxatives was similar between the groups (p = 1.000 and 0.917, respectively). The average duration of prokinetic use was shorter in the intervention group (2.80 ± 1.52 vs. 6.08 ± 5.58 days, 95 % Confidence interval (CI) -1.39; -0.0594, p = 0.011). Although the number of days on mechanical ventilation, ICU stay, and mortality were lower in the patients who received probiotics, no significant differences were observed between the groups (p ≥ 0.05).

CONCLUSION

It is concluded that ICU patients supplemented with probiotics have a shorter duration of prokinetic use. However, supplementation does not directly impact gastrointestinal symptoms, infections, antibiotic use, laxative use, duration of mechanical ventilation, ICU stay, or mortality.

REGISTERED AT

Brazilian Clinical Trials Registry (ReBEC) under the number: ID RBR-2kqnj2t. SITE: https://ensaiosclinicos.gov.br/welcome.

Nutritional Support for Necrotizing Soft Tissue Infection Patients: From ICU to Outpatient Care

Although nutrition recommendations for patients with necrotizing soft tissue infections (NSTIs) often parallel those for patients with burn injuries, differences in the metabolic response to stress indicate that NSTIs require a unique approach. The sepsis and wound management associated with NSTIs trigger a metabolic response, driven by inflammatory and neuroendocrine changes, that leads to high circulating levels of cortisol, catecholamines, insulin, and pro-inflammatory cytokines. This metabolic response follows four phases of recovery (Early Acute; Late Acute; Persistent Inflammation, Immunosuppression, and Catabolism Syndrome; Recovery) that require a thoughtful approach to nutrition by risk screening, malnutrition assessment, and micronutrient deficiency assessment. Close monitoring of energy expenditure and protein needs is required for appropriate nutrition management. Nutrition intake after transfer from the intensive care unit and hospital discharge is often inadequate. Ongoing monitoring of nutrition intake at all outpatient follow-up appointments is necessary, regardless of the route of delivery, until the nutrition status stabilizes and any nutritional decline experienced during hospitalization has been corrected.

The urea-to-creatinine ratio as an emerging biomarker in critical care: a scoping review and meta-analysis

BACKGROUND

Severe protein catabolism is a major aspect of critical illness and leads to pronounced muscle wasting and, consequently, extended intensive care unit (ICU) stay and increased mortality. The urea-to-creatinine ratio (UCR) has emerged as a promising biomarker for assessing protein catabolism in critical illness, which is currently lacking. This review aims to elucidate the role of UCR in the context of critical illness.

METHODS

This scoping review adhered to the PRISMA Extension for Scoping Reviews guidelines. A comprehensive literature search was conducted on the 3rd of September 2024, across Embase, PubMed, ScienceDirect, and Cochrane Library to identify studies related to (1) critically ill adult patients and (2) reporting at least a single UCR value. A meta-analysis was conducted for ≥ 5 studies with identical outcome parameters.

RESULTS

Out of 1,450 studies retrieved, 47 were included in this review, focusing on UCR's relation to protein catabolism and persistent critical illness (10 studies), mortality (16 studies), dietary protein interventions (2 studies), and other outcomes (19 studies), such as delirium, and neurological and cardiac adverse events. UCR is inversely correlated to muscle cross-sectional area over time and associated to length of ICU stay, emphasising its potential role in identifying patients with ongoing protein catabolism. A UCR (BUN-to-creatinine in mg/dL) of ≥ 20 (equivalent to a urea-to-creatinine in mmol/L of approximately 80) upon ICU admission, in comparison with a value < 20, was associated with a relative risk of 1.60 (95% CI 1.27-2.00) and an adjusted hazard ratio of 1.29 (95% CI 0.89-1.86) for in-hospital mortality.

DISCUSSION

UCR elevations during critical illness potentially indicate muscle protein catabolism and the progression to persistent critical illness, and high levels at ICU admission could be associated with mortality. UCR increments during ICU stay may also indicate excessive exogenous dietary protein intake, overwhelming the body's ability to use it for whole-body or muscle protein synthesis. Dehydration, gastrointestinal bleeding, kidney and liver dysfunction, and renal replacement therapy may also influence UCR and are considered potential pitfalls when assessing catabolic phases of critical illness by UCR. Patient group-specific cut-off values are warranted to ensure its validity and application in clinical practice.

Factors influencing the implementation and adherence to volume-based enteral feeding protocols in the critical care setting: A scoping review

OBJECTIVE

Delivery of enteral nutrition is an essential component of care for patients in the intensive care unit (ICU); however, patients only receive approximately 60% of prescribed enteral nutrition. Volume-based feeding (VBF) has been demonstrated as a safe and effective strategy to catch up for missed delivery of enteral nutrition. The aim of this review was to investigate factors influencing the adherence and implementation of VBF in the adult critical care and high-dependency unit settings to inform future implementation of VBF protocols in the ICU.

METHODS

Systematic searches of databases (MEDLINE, EMBASE, and Emcare) and grey literature repositories (TROVE, TRIP, CPG Infobase, WorldCat, and Google) were conducted to identify original research studies including adults admitted to the ICU, where VBF or catch-up feeding protocols were in place. Studies reporting on barriers, enablers, and acceptability or adherence to VBF protocols were included.

RESULTS

A total of 28 studies involving 7057 participants were eligible for inclusion, of which 19 were conducted in the USA, seven in Canada, one in the UK, and one in Australia. Factors enabling the implementation of VBF included management support, multidisciplinary team engagement, a project team, multimodal education, and communication strategies. Embedding the protocol into current work systems increased success. Barriers included a culture of deprioritising nutrition, safety concerns, staff turnover, and failure to embed the changes into work systems including the electronic medical record. VBF was considered acceptable to ICU staff; however, adherence to VBF protocols was variable (between 32.1% and 90%).

CONCLUSION

Successful implementation of a VBF protocol is enabled by strong project leadership, staff education, team engagement, and embedding VBF into current work processes. VBF is acceptable to staff; however, continuous education is recommended to sustain change in practice. Implementation of VBF should be considered as part of an "enhanced" feeding strategy in the ICU setting.

REGISTRATION

The protocol was developed and registered a priori on Open Science Framework on 8th August 2023 (https://doi.org/10.17605/OSF.IO/8DJKY).

[Obesity in intensive care]

The prevalence of obesity and its associated comorbidities are increasing worldwide, leading to a rising proportion of obese patients in hospitals and intensive care units. This trend is causing a significant additional burden on our healthcare system. An obese patient requiring intensive care treatment presents major challenges for the entire team, not only in terms of economic aspects but also medically, in nursing care, and in physiotherapy. Additionally, psychosocial and organizational factors play a role that must be considered. For nursing and physiotherapy, appropriate aids such as lifters, special large hospital beds, suitable rooms, and adequate staffing should be provided. The medical challenges include intubation and airway management, hemodynamic monitoring, vascular access, adequate nutrition, appropriate dosing of medication, and difficult ultrasound conditions at the bedside. Furthermore, this patient population has an increased risk of developing pressure ulcers, pneumonia, and thrombosis, which increase the overall care requirements and further challenge the intensive care setting.

Role of dietitians in optimizing medical nutrition therapy in cardiac surgery patients: A secondary analysis of an international multicenter observational study

BACKGROUND

Better understanding the impact of dietetic services on nutrition practices seems required as it may represent an opportunity for optimization in post-cardiac surgery patients. The present study aims to evaluate and compare nutrition practices and clinical outcomes in post-cardiac surgery intensive care unit (ICU) patients with and without dietetic services.

METHODS

This is a secondary analysis of a multinational prospective observational study in patients (n = 237) with >72 h of post-cardiac surgical ICU stay with and without dietetic services describing nutrition practices and outcomes up to 12 days after ICU admission.

RESULTS

Dietetic services were available in 61.5% (8 of 13) ICUs (1.0 ± 0.5 full-time equivalents/10 beds). Enteral nutrition was initiated <48 h from ICU admission in 49.6% and 59.1% of patients at sites with vs without dietetic services, respectively. Parenteral nutrition was started within 118.3 ± 56.5 and 131.5 ± 69.2 h at sites with vs without dietetic services, respectively. Energy target (23.7 ± 4.8 vs 24.6 ± 4.8 kcal/kg body weight/day) and actual supply (10.5 ± 6.7 vs 10.3 ± 6.2 kcal/kg body weight/day) did not differ between the groups. Protein targets (1.4 ± 0.4 vs 1.1 ± 1.3 g/kg body weight/day) and actual protein provision (0.6 ± 0.4 vs 0.4 ± 0.3 g/kg body weight/day) were higher in patients at sites with vs without dietetic services.

CONCLUSION

Improvements in medical nutrition therapy practices in patients after cardiac surgery are needed in ICUs with and without dietetic services. Appropriately staffed dietetic services as essential members of the medical care team may be crucial to transfer knowledge on adequate medical nutrition therapy strategies into practice.

Measured resting energy expenditure and predicted resting energy expenditure based on ASPEN critical care guidelines for nutrition support: An agreement study

BACKGROUND

Predictive equations often inaccurately estimate energy needs in critically ill patients. This study evaluated the level of agreement between resting energy expenditure using 12 and 25 kcal/kg as recommended by the 2021 American Society for Parenteral and Enteral Nutrition critical care guidelines for nutrition support and energy expenditure measured by indirect calorimetry in patients in the intensive care unit.

METHODS

An agreement study was conducted on mechanically ventilated adults who had a documented measured energy expenditure within 10 days of intensive care unit admission. Agreement was assessed using Bland-Altman plots and Wilcoxon signed rank tests. A subgroup analysis was performed for patients with a body mass index of ≥30 kg/m² using actual body weight, adjusted body weight, and ideal body weight. Correlations between measured energy expenditure and patient characteristics were also explored.

RESULTS

Fifty-eight patients were included and were a median age of 64 years, 63.8% male, and a median body mass index of 28.0 kg/m2. The 12 kcal/kg and 25 kcal/kg differed significantly from measured energy expenditure (P < 0.001). Bland-Altman plots showed mean biases of -644.6 kcal/day for 12 kcal/kg and 406.5 kcal/day for 25 kcal/kg. In the body mass index ≥30 kg/m² subgroup (n = 22), 12 kcal/kg underestimated measured energy expenditure across all weights, and 25 kcal/kg was more accurate when using ideal or adjusted body weights.

CONCLUSIONS

Predicted energy expenditure using 12 kcal/kg and 25 kcal/kg based on the 2021 American Society for Parenteral and Enteral Nutrition critical care guidelines for nutrition support had poor agreement with measured energy expenditure in mechanically ventilated patients.

Investigating key factors of feeding intolerance in sepsis: A scoping review

BACKGROUND

At present, domestic and international research on the current status of feeding intolerance in septicemia patients only stops at the study of influencing factors; however, due to the specificity of the disease, the influencing factors are numerous and controversial.

AIMS

To systematically analyse the studies related to the occurrence of feeding intolerance in patients with sepsis, to find out the influencing factors of feeding intolerance in these patients and to provide a reference for nursing staff to develop relevant interventions.

STUDY DESIGN

The study employed Arksey and O'Malley's methodology to carry out a scoping review. We conducted a systematic search, using the scoping review as a framework, for relevant Chinese and English literature on factors influencing feeding intolerance in patients with sepsis in China Knowledge Network, Wanfang, CINAHL, Pubmed, Web of Science and Google Scholar, covering a time frame from construction to 1 September 2024. We identified research questions, completed literature screening and quality assessment, extracted data and summarized and analysed the data.

RESULTS

The review included a total of 13 papers. Factors influencing feeding intolerance in septicemia patients included patient factors, disease factors, biochemical indicators, feeding determinants, clinical treatment and drug effects.

CONCLUSIONS

Factors affecting feeding intolerance in patients with sepsis are multifaceted. We should develop individualized care plans based on relevant risk factors to improve feeding tolerance and shorten hospital stays in patients with sepsis.

RELEVANCE TO CLINICAL PRACTICE

In order to improve the ability of ICU nurses to identify the risk factors of feeding intolerance in patients with sepsis, it is recommended to conduct systematic training on the pathophysiology of sepsis, influencing factors of feeding intolerance and intervention measures and assist nurses to implement appropriate intervention measures.

Sarcopenia and frailty in critical illness

PURPOSE OF REVIEW

Sarcopenia and frailty are common conditions, associated with worse clinical outcomes during critical illness. Recent studies on sarcopenia and frailty in ICU patients are presented in this review, aiming to identify accurate diagnostic tools, investigate the effects on clinical and functional outcomes, and propose possible effective interventions.

RECENT FINDINGS

The recent change of the sarcopenia definition underlines the importance of muscle strength over mass, this is however challenging to assess in ICU patients. There is currently no unified sarcopenia definition, nor standard frailty assessment tool; Clinical Frailty Scale is most frequently used in the ICU. Meta-analyses show worse clinical and functional outcomes for frail as well as sarcopenic patients admitted to the ICU, regardless of admission diagnosis. Frailty is a dynamic condition, worsening in severity by the time of hospital discharge, but showing improvement by 6 months post-ICU. Therapeutic interventions for frailty and sarcopenia remain limited. Although mobilization strategies show promise in improving functional and cognitive outcomes, inconsistent outcomes are reported. Heterogeneity in definitions, patient populations, and care practices challenge interpretation and comparison of study results and recognition of beneficial interventions. This highlights the need for more research.

SUMMARY

The importance of preexisting sarcopenia and frailty is recognized in ICU patients and associated with worse clinical outcomes. Multidimensional interventions are most promising, including patient-tailored mobilization and nutrition.

The association between body mass index and ICU 28-day mortality rate in patients with sepsis: A retrospective observational study

OBJECTIVES

Sepsis remains the major cause of mortality among critically ill patients worldwide, indicating the importance of better understanding of its influencing factors for fast recognition and management. Although greater concerns have been raised about the "obesity paradox" and sepsis related mortality, the evidence regarding on overweight or obese septic patients is still controversial. To provide more clinical evidence for the exploration of body mass index (BMI) on sepsis prognostic prediction, we assessed the association of BMI with 28-day mortality of septic patients in intensive care unit (ICU).

METHODS

This was a retrospective observational study with patient data extracted from the eICU Collaborative Research Database. We employed a logistic regression to assess the effect of admission BMI levels on sepsis related mortality risk. Furthermore, the two-piecewise linear model was used to identify BMI mortality thresholds, and BMI-outcome associations were evaluated by interaction tests and subgroup analyses.

RESULTS

Our cohort included a total of 17,454 patients, of whom 1555 (8.91 %) died within 28 days after being admitted to the ICU. The connection between BMI and 28-day mortality in the ICU displayed a U-shaped curve. The threshold effect analysis results in two inflection points of BMI were 23.62 kg/m2 and 45.53 kg/m2. When the BMI was <23.62 kg/m2, the mortality rate decreased by 7 % (95 %CI 0.91, 0.96, P<0.0001) for every 1 increment in the BMI. When the BMI was ≥45.53 kg/m2, the mortality rate increased by 8 % (95 %CI 1.01,1.15, P = 0.0322) for every 1 increment in the BMI. Subgroup analysis showed that neither age nor sex covariates affected the stability of these results (all P for interaction≥0.05).

CONCLUSIONS

In septic ICU patients, the correlation between BMI and 28-day mortality exhibited a U-shaped pattern, indicating that both low and extremely high BMIs were linked to a heightened risk of mortality within 28 days.

Use of erythromycin and metoclopramide in hospitalized dogs: a multicenter historical cohort study

Introduction

Prokinetics are used to treat gastrointestinal (GI) dysmotility in critically ill dogs but there have been no published studies characterizing their use. The objective of this multi-institutional retrospective cohort study was to describe the use of the prokinetics erythromycin and metoclopramide in dogs hospitalized in two institutions. We hypothesized that there would be change over time and differences between institutions in the use of erythromycin and metoclopramide.

Methods

Dogs for inclusion were identified by fee code searches for injectable erythromycin and metoclopramide in the electronic medical record systems of The Animal Hospital at Murdoch University and Western Australian Veterinary Emergency and Specialty Hospital for the years 2018 and 2023. 75 cases from each hospital in each year were selected for inclusion from the search results using a formal randomization procedure to yield a total case number of 300. Data collected for each dog included signalment, diagnosis, reason(s) for starting prokinetics, the injectable prokinetic(s) used, frequency, and doses. Chi square or Fisher's exact tests were used as appropriate to compare the proportions of dogs receiving metoclopramide alone, erythromycin alone, or both prokinetics in 2018 and 2023, the proportions of dogs receiving metoclopramide or erythromycin as sole prokinetics between the two institutions, and the proportions of dogs receiving a single prokinetic versus dual prokinetics between the two institutions.

Results

Primary GI diseases accounted for the majority of the diagnoses. The most common reasons for starting a prokinetic were vomiting, an imaging diagnosis of ileus, prophylaxis following abdominal surgery, and regurgitation. Metoclopramide was administered as a sole prokinetic in the majority of dogs, fewer cases received erythromycin alone, or both prokinetics. Use of metoclopramide alone decreased from 2018 to 2023, with more dogs receiving erythromycin alone or both prokinetics in 2023. There were also significant differences in prokinetic use between institutions.

Discussion

Prospective studies to investigate the effectiveness and safety of metoclopramide and erythromycin as prokinetics in dogs are warranted.

Nutritional adequacy in critically ill adults receiving noninvasive ventilation: A descriptive cohort study

BACKGROUND

Noninvasive ventilation (NIV) is increasingly being used in critical care, yet limited evidence exists guiding nutrition practices for patients who are critically ill receiving NIV. This study aimed to describe the nutrition practices and adequacy of nutrition intake among patients who are critically ill receiving NIV.

METHODS

This descriptive cohort study included adult patients admitted to critical care who received NIV on ≥3 consecutive days. Prospectively recorded clinical data were retrospectively extracted from electronic medical records and compared between patients who received solely noninvasive ventilation (NIV only) and those who received invasive mechanical ventilation (IMV) and were extubated onto noninvasive ventilation (post-IMV group).

RESULTS

Of the 220 patients included (107 NIV only; 113 post-IMV), 142 (64.5%) received exclusive oral nutrition, 66 (30.0%) received artificial nutrition support, and 12 (5.5%) received no nutrition. Enteral nutrition was more prevalent in the post-IMV group (36 [31.9%] vs NIV only 19 [17.8%]; P = 0.01), whereas exclusive oral nutrition was more prevalent in the NIV-only group (86 [80.4%] vs post-IMV 66 [58.4%]; P < 0.001). Most patients who received purely exclusive oral nutrition (n = 152) had inadequate intake (94 [61.8%]).

CONCLUSION

Most patients with critically illness receiving NIV received exclusive oral nutrition, which was found to be inadequate in the majority. Patients receiving NIV represent a nutritionally at-risk population, and future studies are needed to understand the barriers to oral intake and the feasibility, safety, and effectiveness of enteral nutrition.

Risk factors for enteral feeding intolerance in critically ill patients: an updated systematic review and meta-analysis

BACKGROUND

This meta-analysis aimed to evaluate the factors influencing enteral nutrition feeding intolerance in critically ill patients.

METHODS

PubMed, Embase, Scopus, Medline, Web of Science, CNKI, VIP, WanFang and CBM databases were searched. A sensitivity analysis was carried out to explore the influence of individual studies on the pooled results of the included studies using a fixed-effects model or a random-effects model. The pooled results were expressed as the odds ratios (ORs) and 95% confidence intervals (Cls). Finally, a funnel plot was developed to describe the publication bias.

RESULTS

Twenty-three studies involving 30,688 participants were included. Meta-analysis results showed that age, body mass index (BMI), APACHE II score, renal insufficiency, digestive system diseases, hypoproteinemia, sepsis, and post-pyloric feeding, starting feeding within 48 h, feeding pattern, nutritional formula, sedative drugs, vasoactive drugs, use of more than two antibiotics, oral potassium preparation, mechanical ventilation, days of mechanical ventilation, length of ICU stay, and mortality were the influencing factors of enteral nutrition feeding intolerance in critically ill patients. The results of the sensitivity analysis showed that the direction of the pooled effect size did not change after excluding each study one by one, suggesting that the results of the meta-analysis were robust.

CONCLUSIONS

According to the influencing factors, medical staff can pay attention to the high-risk patients at ICU admission to reduce the risk of feeding intolerance.

The Impact of Protein Feed on the Urea-to-Creatinine Ratio-A Retrospective Single-Center Study

BACKGROUND/OBJECTIVES

The urea-to-creatinine ratio (UCR) serves as a biochemical marker for catabolism in the intensive care unit (ICU). UCR increases mainly due to an elevated urea generation from increased protein metabolism. This study aimed to evaluate the impact of protein intake on UCR progression in ICU patients.

METHODS

The inclusion criteria of this retrospective, single-center analysis required an ICU stay of at least 14 days without requirement of renal replacement therapy (n = 346 patients). Patients were grouped based on daily mean protein intake per kilogram between days 5 and 14: low (≤0.8 g/kg/d, n = 120), medium (0.9-1.2 g/kg/d, n = 132), and high (≥1.3 g/kg/d, n = 94). Data on daily protein and calorie intake, calorie deficit, urea generation rate, serum creatinine, urea, UCR and creatinine clearances were analysed. Risk factors for developing a high UCR were determined via logistic regression analysis adjusted for sex, age, bodyweight, disease severity (SAPS III admission score) as well as mean protein intake and calorie deficit during day 5 and 14 on ICU.

RESULTS

Higher protein intake was associated with increased calorie intake, lower calorie deficit, and led to an elevated urea generation rate and higher UCR. Renal function and serum urea trends were comparable between all groups, while creatinine was significantly lower in the high-protein group. Risk factors for developing an elevated UCR included older age, female sex and higher protein intake.

CONCLUSIONS

An elevated UCR in the early ICU phase may indicate an increased protein metabolism, not only deriving from catabolism but also from a high protein feed.

Impact of patient safety on outcomes. From prevention to the treatment of post-intensive care syndrome

Survivors of critical illness may present physical, psychological, or cognitive symptoms after hospital discharge, encompassed within what is known as post-intensive care syndrome. These alterations result from both the critical illness itself and the medical interventions surrounding it. For its prevention, the implementation of the ABCDEF bundle (Assess/treat pain, Breathing/awakening trials, Choice of sedatives, Delirium reduction, Early mobility and exercise, Family) has been proposed, along with additional strategies grouped under the acronym GHIRN (Good communication, Handout materials, Redefined ICU architectural design, Respirator, Nutrition). In addition to these preventive measures during the ICU stay, high-risk patients should be identified for subsequent follow-up through multidisciplinary teams coordinated by Intensive Care Medicine Departments.

Enhanced metabolic regulation in II/R injury: Comparing multiroute and monoroute enteral nutrition

OBJECTIVE

This study aimed to compare the effects of enteral nutrition (EN) administered via multiroute or via monoroute on metabolic regulation in intestinal ischemia-reperfusion (II/R) injury rat model.

METHODS

The rats were divided into sham operation and II/R injury groups. The rats in each group were further treated with either multiroute or monoroute EN. Rats subjected to multiroute EN were administered a continuous infusion of 30 kcal/kg × day of nutrition via a gastric tube and additionally provided with 0.5 g of standard rat forage for oral intake q8h (for a total of approximately 20 kcal/kg × day) each day. Conversely, rats on the monoroute regimen underwent a continuous infusion of 50 kcal/kg × day of EN through a gastric tube. Hypercatabolism was evaluated by assessing skeletal muscle protein synthesis and atrophy, and insulin resistance. Moreover, serum gastrointestinal hormone levels, hypothalamic ghrelin, and neuropeptide pro-opiomelanocortin (POMC) were detected.

RESULTS

In rats subjected to II/R injury, multiroute EN more effectively restored serum and hypothalamic ghrelin levels, decreased the expression of the POMC neuropeptide, decreased skeletal muscle atrophy, and enhanced skeletal muscle synthesis. These effects collectively contributed to a reduction in muscle wasting, an improvement in hypercatabolic status, and a mitigation of body weight loss.

CONCLUSION

Compared with monoroute nutrition, multiroute EN may further improve hypercatabolic metabolism, reduce muscle wasting, and prevent weight loss in II/R injury rat. This research suggested that an optimized multiroute EN regimen is superior to the monoroute EN approach.

Measured energy expenditure according to the phases of critical illness: A descriptive cohort study

BACKGROUND

Indirect calorimetry is recommended for directing energy provision in the intensive care unit (ICU). However, limited reports exist of measured energy expenditure according to the phases of critical illness in large cohorts of patients during ICU admission. This study aimed to analyze measured energy expenditure overall in adult patients who were critically ill and across the different phases of critical illness.

METHODS

Indirect calorimetry measurements completed at a mixed ICU between January 2010 and July 2019 were eligible. Measured energy expenditure was analyzed and reported as kcal/day and kcal/kg/day overall, as the percentage increase above predicted basal metabolic rate and according to the phases of critical illness; acute early (day 1-2), acute late (day 3-7) and recovery (>7 days) phases using mixed effects linear modelling.

RESULTS

There were 629 patients with 863 measurements included; age mean (standard deviation) 48 (18) years, 68% male and 269 (43%) with a traumatic brain injury. Measured energy expenditure overall was 2263 (626) kcal/day (30 (7) kcal/kg/day), which corresponded to a median [interquartile range] of 135 [117-155] % increase above predicted basal metabolic rate. In patients with repeat measurements (n = 158), measured energy expenditure (mean ± standard error) increased over time; 27 ± 0.5 kcal/kg/day in the early acute, 30 ± 0.4 kcal/kg/day in the late acute, and 31 ± 0.4 kcal/kg/day in the recovery phases of critical illness (P < 0.001).

CONCLUSION

In a large cohort of ICU patients, measured energy expenditure was 135% above the basal metabolic rate and increased from the early acute to the late acute and recovery phases of critical illness.

Protein Delivery in Critical Care- What Have Recent Trials Shown Us?

Determining the optimal protein intake for intensive care unit (ICU) and post-ICU patients is a multifaceted challenge. Firstly, it is essential to avoid both underdosing (<1.0 g/kg) and overdosing (>1.6 g/kg) of actual protein intake. Secondly, the actual protein intake may deviate from the prescribed amount. Thirdly, phenotyping and endotyping are becoming increasingly crucial in tailoring protein targets. Additionally, a gradual increase in protein intake is essential during the first 4 to 5 days of ICU stay. Furthermore, no established protein targets exist for post-ICU patients, indicating the need for nutritional intervention research to identify optimal protein intake strategies.

Gastrointestinal dysmotility in the ICU

PURPOSE OF REVIEW

This review aims to provide a comprehensive overview of gastrointestinal dysmotility, particularly in critically ill patients within the ICU. It highlights the pathophysiology, prevalence, and clinical implications of conditions, such as oesophageal dysmotility, gastroparesis, ileus, and Ogilvie's syndrome. By examining current diagnostic and treatment approaches, the review emphasizes the importance of recognizing and managing gastrointestinal dysmotility to improve patient outcomes.

RECENT FINDING

Recent literature indicates that up to 60% of ICU patients experience some form of gastrointestinal dysmotility, with those on mechanical ventilation being particularly at risk. The review identifies key contributors to gastrointestinal dysmotility, including inflammatory states, electrolyte imbalances, and the effects of certain medications. Nonpharmacological strategies, such as early enteral feeding, correcting electrolyte abnormalities, and mobilization are critical. Prokinetic agents have shown promise in alleviating feeding intolerance and improving gastric emptying, though their effects on overall mortality remain inconclusive.

SUMMARY

Gastrointestinal dysmotility presents a significant challenge in critically ill patients, leading to various complications that hinder recovery. Understanding the underlying pathophysiology, coupled with effective diagnostic and treatment strategies, is essential for enhancing patient care. This review underscores the need for continued research and clinical focus on gastrointestinal motility disorders in the ICU to improve health outcomes for this vulnerable population.

Why One-Size-Fits-All Doesn't Work in Intensive Care Unit Nutrition?

Nutrition therapy is a complex intervention with several underlying considerations that may influence effectiveness. Considerations include the mechanism of action of the intervention and the patient phenotype, including sex, ethnicity, body composition, and the patients' nutritional and inflammatory status. Energy and protein targets are elements of nutrition therapy that may be particularly influenced by individual patient factors. Biomarkers may provide a useful tool to monitor and individualize nutrition therapy in the future. The considerations mentioned, with many yet to be studied, highlight the rationale for more individualized interventions moving away from a 'one-size-fits-all' approach.

Early Feeding in Critical Care - Where Are We Now?

The aim to avoid underfeeding has resulted in relative overfeeding of patients in the early phase of critical illness, worsening instead of improving outcomes. Negative randomised controlled trials have triggered mechanistic studies to investigate possible mechanisms explaining harm, allowing more scientific interpretation of many unexpected results during the last decades. Whereas individualized evidence-based approach to nutrition is still only rarely available, discussing and understanding of pathophysiological mechanisms should assist in decision-making in clinical practice. Further exploration of mechanisms of harm and benefit, as well as development of new technologies are needed to better plan future nutrition studies.

Sequential versus continuous feeding and its effect on the gut microbiota in critically ill patients: A randomized controlled trial

BACKGROUND

Gut microbiota disturbance may worsen critical illnesses and is responsible for the progression of multiple organ dysfunction syndrome. In our previous study, there was a trend towards a higher α-diversity of the gut microbiota in sequential feeding (SF) than in continuous feeding (CF) for critically ill patients. We designed this non-blinded, randomized controlled study to confirm these results.

METHODS

All the enrolled patients received continuous feeding in the beginning. After achieving ≥80 % of the nutrition target calories (25-30 kcal/kg/d), the patients were randomized into the SF group or the CF group. In the SF group, continuous feeding was changed into intermittent feeding. The total daily dosage of enteral nutrition was equally distributed during three periods at 7-9:00, 11-13:00 and 17-19:00. After 7 days of randomization, fresh stool and serum were collected for 16S rRNA gene sequencing and untargeted metabolomics analysis respectively. Meanwhile, routine blood test indicators and metabolic indicators were recorded.

RESULTS

Finally, data from 65 patients in the SF group and 69 patients in the CF group were used for intention-to-treat analysis. There was no difference in the Shannon index between the SF group and CF group [2.5 (1.7-3.4) vs. 2.6 (1.5-3.5), P = 0.934]. However, at the genus level, the abundances of Erysipelotrichaceae_UCG-003 and Howardella increased in the SF group. Some metabolic indicators (the albumin level, total cholesterol level and total bile acid level) and the increases in lymphocyte counts in the SF group were different from those in the CF group (P < 0.05). In untargeted metabolomic analysis, 58 differentially abundant metabolites between the two groups were found. The pathway with the highest enrichment factors was primary bile acid biosynthesis according to the Kyoto Encyclopedia of Genes and Genomes Database classification. Regarding adverse events, the gut tolerance, average glucose and incidence of hyperglycemia and hypoglycemia were similar between the SF group and CF group. The mortality rate in the SF group was lower than that in the CF group, but there was no statistical difference (9.2 % vs. 13.0 %, P = 0.484).

CONCLUSION

SF did not increase the diversity of gut microbiota in critically ill patients. However, it did alter the abundances of some gut microbes and affect some metabolites. Its clinical significance requires further exploration. In addition, the gut tolerance and safety of SF were similar to that of CF.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov, registration number NCT04443335. Registered 21 June, 2020.

Advances in management strategies for enteral nutrition-related gastric retention in adult patients with nasogastric tubes

Gastric retention is a common complication in individuals receiving enteral nutrition (EN) via a nasogastric tube, increasing the risk of aspiration pneumonia and causing unnecessary interruptions in nutritional support. Given its clinical significance, establishing effective, evidence-based, and standardized management strategies is essential for bettering patient outcomes and mitigating complications. This review systematically synthesized the diagnostic criteria, assessment methods, influencing factors, management procedures, and intervention strategies for gastric retention in EN patients. Although no universal consensus exists regarding gastric residual volume (GRV) thresholds, evidence indicates that EN can continue at high GRV levels in the absence of gastrointestinal symptoms. Bedside ultrasound emerged as a non-invasive, and precise method GRV assessment, offering potential to standardize clinical practice. Key risk factors for gastric retention include neurological disorders and EN infusion rates exceeding 100 mL/h. Effective management strategies encompass non-pharmacological interventions, pharmacological agents, and traditional Chinese medicine (TCM) therapies. This review underscored the need for integrated, multi-modal management strategies and recommended the adoption of bedside ultrasound and standardized protocols to optimize EN delivery and improve patient outcomes. Large-scale, multicenter clinical trials should be a priority for future investigation to verify the effectiveness of TCM therapies and develop personalized intervention plans for high-risk patients.

Malnutrition and perioperative nutritional rehabilitation in major operations

Background

Malnutrition is a potentially preventable risk factor for surgery. This systematic review examines nutritional management strategies aiming to enhance surgical outcomes.

Methods

A systematic search was conducted in PubMed for English-language studies published between July 1, 2004, and July 1, 2024, involving adult surgical patients. Study selection focused on four key themes: (1) nutritional screening and assessment, (2) preoperative nutritional therapy, (3) nutritional support in critically ill surgical patients, and (4) postoperative nutritional rehabilitation. Studies in non-surgical cohorts, letters, and case reports were excluded. Reference lists of relevant studies were manually screened for additional sources.

Results

Of 2763 studies identified, 251 met the inclusion criteria and 85 were added after manual screening, contributing to a total of 341 papers for the review. The prevalence of malnutrition varied widely by procedure, with the highest rates observed in pancreatic and esophagogastric operations. Preoperative malnutrition was strongly associated with increased postoperative complications, infections, prolonged hospital stay, and higher mortality. The Malnutrition Universal Screening Tool (MUST) was effective in identifying at-risk patients. Preoperative nutritional interventions, including dietitian-led counseling, oral supplementation, and enteral or parenteral nutrition, may reduce complications and improve outcomes. Critically ill patients benefited from structured enteral and parenteral strategies. Early postoperative nutrition within enhanced recovery after surgery (ERAS) protocols are linked to less complications and shorter hospital stay.

Conclusion

Malnutrition significantly impacts surgical outcomes, necessitating early identification and intervention. Standardized management is key to improving recovery and reducing complications. Future research should focus on refining diagnostic tools, assessing nutritional requirements, optimizing perioperative nutritional strategies, and establishing long-term nutritional follow-up guidelines for surgical patients.

The Japanese Critical Care Nutrition Guideline 2024

Nutrition therapy is important in the management of critically ill patients and is continuously evolving as new evidence emerges. The Japanese Critical Care Nutrition Guideline 2024 (JCCNG 2024) is specific to Japan and is the latest set of clinical practice guidelines for nutrition therapy in critical care that was revised from JCCNG 2016 by the Japanese Society of Intensive Care Medicine. An English version of these guidelines was created based on the contents of the original Japanese version. These guidelines were developed to help health care providers understand and provide nutrition therapy that will improve the outcomes of children and adults admitted to intensive care units or requiring intensive care, regardless of the disease. The intended users of these guidelines are all healthcare professionals involved in intensive care, including those who are not familiar with nutrition therapy. JCCNG 2024 consists of 37 clinical questions and 24 recommendations, covering immunomodulation therapy, nutrition therapy for special conditions, and nutrition therapy for children. These guidelines were developed in accordance with the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system by experts from various healthcare professionals related to nutrition therapy and/or critical care. All GRADE-based recommendations, good practice statements (GPS), future research questions, and answers to background questions were finalized by consensus using the modified Delphi method. Strong recommendations for adults include early enteral nutrition (EN) within 48 h and the provision of pre/synbiotics. Weak recommendations for adults include the use of a nutrition protocol, EN rather than parenteral nutrition, the provision of higher protein doses, post-pyloric EN, continuous EN, omega-3 fatty acid-enriched EN, the provision of probiotics, and indirect calorimetry use. Weak recommendations for children include early EN within 48 h, bolus EN, and energy/protein-dense EN formulas. A nutritional assessment is recommended by GPS for both adults and children. JCCNG 2024 will be disseminated through educational activities mainly by the JCCNG Committee at various scientific meetings and seminars. Since studies on nutritional treatment for critically ill patients are being reported worldwide, these guidelines will be revised in 4 to 6 years. We hope that these guidelines will be used in clinical practice for critically ill patients and in future research.

An alternative method to differentiate pleural effusion after leakage of artificial enteral nutrition formula

PURPOSE

This case report highlights a rare but fatal complication of artificial enteral nutrition due to feeding tube misplacement, leading to pleural effusion and respiratory failure. The primary objective was to determine whether enteral nutrition formula leakage contributed to the patient's death and to differentiate the pleural effusion from other possible etiologies, such as chylothorax.

METHODS

A 59-year-old male patient with severe lung disease underwent left-sided partial lung resection and subsequently received enteral nutrition via a nasogastric feeding tube. After suspected feeding tube misplacement and formula leakage into the pleural cavity, autopsy and histological examination were performed. Cytological and chemical analyses, including gas chromatography-mass spectrometry, were employed to identify nutritional components in pleural effusion and to confirm the presence of enteral nutrition formula.

RESULTS

The autopsy revealed milky, turbid pleural effusion, aspiration pneumonia, and a rupture of the right visceral pleura. Cytological analysis confirmed granulocytic pleural empyema with rod-shaped Congo red-positive material resembling the enteral nutrition formula. Gas chromatography-mass spectrometry identified tricaprylin, a unique marker for enteral nutrition formula, confirming nutritional leakage into the pleural cavity.

CONCLUSIONS

This case study emphasizes the necessity for radiological confirmation of feeding tube placement and the implementation of comprehensive diagnostic protocols for suspected cases of nutritional fluid leakage. Gas chromatography-mass spectrometry proved invaluable in distinguishing nutritional effusions from other potential etiologies by enabling the specific identification of enteral formula components. The high specificity and adaptability of gas chromatography-mass spectrometry render it an essential tool for forensic investigations and clinical diagnostics involving complex fluid analyses, facilitating evidence-based conclusions in critical care and postmortem contexts.

Combined Effects of Early Mobilization and Nutrition on ICU-Acquired Weakness

Intensive Care Unit-Acquired Weakness (ICUAW) is a very common condition in patients admitted to intensive care units (ICUs), even after relatively short stays. This weakness can develop with a pre-existing background of sarcopenia or cachexia, although these conditions are not always the direct cause. Over the years, much of the literature has focused on the nutritional aspect of the issue, leading to the development of widely accepted guidelines recommending the initiation of early nutrition, with the goal of achieving caloric and protein targets within the first five days of ICU admission. Despite adherence to these guidelines, several studies have shown a significant loss of muscle mass in critically ill patients, which directly impacts their ability to generate strength. However, it has become increasingly evident that nutrition alone is not sufficient to counteract this muscle loss, which is often closely linked to the prolonged immobility experienced by ICU patients due to a variety of clinical and logistical factors. In particular, there is growing evidence suggesting that even the introduction of early and minimal rehabilitation-including passive mobilization-when combined with appropriate nutritional support, can be a valuable strategy to help reduce the incidence of ICUAW. In this narrative review, we aim to summarize the current scientific knowledge on this topic, emphasizing the importance of an integrated approach that combines nutrition and early mobilization. Such a combined strategy not only holds the potential to reduce the acute incidence of ICUAW but also contributes to better recovery outcomes and, eventually, improved quality of life for these patients.

Gut integrity in intensive care: alterations in host permeability and the microbiome as potential therapeutic targets

BACKGROUND

The gut has long been hypothesized to be the "motor" of critical illness, propagating inflammation and playing a key role in multiple organ dysfunction. However, the exact mechanisms through which impaired gut integrity potentially contribute to worsened clinical outcome remain to be elucidated. Critical elements of gut dysregulation including intestinal hyperpermeability and a perturbed microbiome are now recognized as potential therapeutic targets in critical care.

MAIN BODY

The gut is a finely tuned ecosystem comprising ~ 40 trillion microorganisms, a single cell layer intestinal epithelia that separates the host from the microbiome and its products, and the mucosal immune system that actively communicates in a bidirectional manner. Under basal conditions, these elements cooperate to maintain a finely balanced homeostasis benefitting both the host and its internal microbial community. Tight junctions between adjacent epithelial cells selectively transport essential molecules while preventing translocation of pathogens. However, critical illness disrupts gut barrier function leading to increased gut permeability, epithelial apoptosis, and immune activation. This disruption is further exacerbated by a shift in the microbiome toward a "pathobiome" dominated by pathogenic microbes with increased expression of virulence factors, which intensifies systemic inflammation and accelerates organ dysfunction. Research has highlighted several potential therapeutic targets to restore gut integrity in the host, including the regulation of epithelial cell function, modulation of tight junction proteins, and inhibition of epithelial apoptosis. Additionally, microbiome-targeted therapies, such as prebiotics, probiotics, fecal microbiota transplantation, and selective decontamination of the digestive tract have also been extensively investigated to promote restoration of gut homeostasis in critically ill patients. Future research is needed to validate the potential efficacy of these interventions in clinical settings and to determine if the gut can be targeted in an individualized fashion.

CONCLUSION

Increased gut permeability and a disrupted microbiome are common in critical illness, potentially driving dysregulated systemic inflammation and organ dysfunction. Therapeutic strategies to modulate gut permeability and restore the composition of microbiome hold promise as novel treatments for critically ill patients.

Evidence Summary of Early Enteral Nutrition Support for Adult Patients with Extracorporeal Membrane Oxygenation (ECMO)

Objective

This study aims to systematically review and summarize the evidence on early enteral nutrition (EEN)support for Extracorporeal Membrane Oxygenation (ECMO)patients, Offer evidence-based guidance to healthcare professionals, including doctors and nurses, to inform their clinical practices.

Methods

Using the "6S"evidence-based model, we searched multiple databases including UpToDate, Best Practice, Guideline International Network (GIN), National Guideline Clearinghouse (NGC),Registered Nurses' Association of Ontario (RNAO), Joanna Briggs Institute (JBI), Evidence-Based Healthcare Center database, the Cochrane Library, PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI),Wanfang Database, and Chinese Biomedical Literature Database (CBM). Aiming to find evidence on early enteral nutrition support for adult patients with extracorporeal membrane oxygenation. The search included clinical decisions, guidelines, systematic reviews, evidence summaries, and expert consensus. The time frame for the search was from the inception of the databases to September 10, 2024.Two researchers evaluated the quality of the collected literature and extracted data and summarized evidence from publications that met the quality criteria.

Results

We retrieved 13 relevant documents, consisting of 6 guidelines, 3 expert consensus papers, 2 clinical decision-making articles, and 2 cohort studies. Through summarization and induction, a total of 26 best evidence pieces were obtained across five aspects: the establishment of nutritional support plans; strategies and risk assessment for enteral nutrition; the implementation of early enteral nutrition supplementation strategies; the amount and composition of nutrients reaching standard intake; and prevention of enteral nutrition-related complications.

Conclusion

This study has summarized the evidence regarding early enteral nutrition support for adult patients with extracorporeal membrane oxygenation (ECMO). It provides an evidence-based foundation for the practice of nursing and assists medical staff in developing personalized nutrition management plans for enteral nutrition support in ECMO patients.