Caloric intake in medical ICU patients: consistency of care with guidelines and relationship to clinical outcomes

Nine Myths about Enteral Feeding in Critically Ill Adults: An Expert Perspective

Malnutrition is a well-studied and significant prognostic risk factor for morbidity and mortality in critically ill perioperative patients. Common nutrition myths in the critically ill may prevent early, consistent, and adequate delivery of enteral nutrition. We outlined 9 common intensive care unit (ICU) nutrition misconceptions and our recommendations to optimize enteral nutrition in critically ill patients based on the review of available literature. Our approach is to treat every patient admitted to the ICU as at risk for malnutrition and to initiate enteral nutrition upon admission in the absence of contraindications. Early enteral nutrition via the gastric route is more beneficial than delaying feeding while awaiting small bowel access and daytime-intermittent nutrition support can safely be initiated over continuous feeding. Gastric residual volumes to assess feeding tolerance should no longer be routinely measured. For perioperative nutrition, we recommend continuing enteral nutrition for most patients with secure airways undergoing anesthesia and resuming nutrition within 24 h of abdominal surgery; even patients with open abdomens can be safely fed in the absence of bowel injury. Critically ill patients who are proned, paralyzed, and on vasopressors can usually continue enteral nutrition. Finally, continuing enteral nutrition before extubation may optimize nutrition without compromising extubation success. In this review, we highlight several common misconceptions regarding ICU nutrition that may prevent achieving nutrition goals and subsequently lead to increased malnutrition, morbidity, and mortality. This knowledge may contribute to increased implementation of early and consistent enteral nutrition strategies to improve outcomes in critically ill adult patients.

Early goal enteral nutrition associated with decreased in-hospital death in mechanically ventilated critically ill adults: a retrospective cohort study

INTRODUCTION

Early enteral nutrition (EN) in critically ill adult patients is thought to improve mortality and morbidity; expert guidelines recommend early initiation of EN in critically ill adults. However, the ideal schedule and dose of EN remain understudied.

STUDY OBJECTIVE

Our objective was to evaluate the relationship between achieving 70% of recommended EN within 2 days of intubation ('early goal EN') and clinical outcomes in mechanically ventilated medically critically ill adults. We hypothesised that early goal EN would be associated with reduced in-hospital death.

METHODS

We conducted a retrospective cohort study of mechanically ventilated adult patients admitted to our medical intensive care unit during 2013-2019. We assessed the proportion of recommended total EN provided to the patient each day following intubation until extubation, death or 7 days whichever was shortest. Patients who received 70% or more of their recommended total daily EN within 2 days of intubation (ie, 'baseline period') were considered to have achieved 'early goal EN'; these patients were compared with patients who did not ('low EN'). The primary outcome was in-hospital death; secondary outcomes were successful extubation and discharge alive.

RESULTS

938 patients met eligibility criteria and survived the baseline period. During the 7-day postintubation period, 64% of all patients reached 70% of recommended daily calories; 33% of patients achieved early goal EN. In unadjusted and adjusted models, early goal EN versus low EN was associated with a lower incidence of in-hospital death (subdistribution HR (SHR) unadjusted=0.63, p=0.0003, SHR adjusted=0.73, p=0.02). Early goal EN was also associated with a higher incidence of successful extubation (SHR unadjusted=1.41, p<0.00001, SHR adjusted=1.27, p=0.002) and discharge alive (SHR unadjusted=1.54, p<0.00001, SHR adjusted=1.24, p=0.02).

CONCLUSIONS

Early goal EN was associated with significant improvement in clinical metrics of decreased in-hospital death, increased extubation and increased hospital discharge alive.

Nutritional Support in Critically Ill Trauma Patients

Enteral nutrition should be initiated within 24 to 48 hours of injury, starting at a trophic rate and increasing to goal rate after hemodynamic stability is achieved. The modified Nutritional Risk in the Critically Ill score can help identify patients who will benefit most from aggressive and early nutritional intervention. In the first week of critical illness, the patient should receive only 70% to 80% of estimated calories and protein should be targeted to 1.5 to 2 g/kg. Parenteral nutrition can be provided safely without increased adverse events. Peri-operative (and intra-operative) feeding has been shown to be safe in selected patients.

Injectable Lipid Emulsion and Clinical Outcomes in Patients Exclusively Receiving Parenteral Nutrition in an ICU: A Retrospective Cohort Study Using a Japanese Medical Claims Database

Guidelines for the nutritional management of critically ill patients recommend the use of injectable lipid emulsion (ILE) as part of parenteral nutrition (PN). The ILE's impact on outcomes remains unclear. Associations between prescribed ILE and in-hospital mortality, hospital readmission, and hospital length of stay (LOS) in critically ill patients in the intensive care unit (ICU) were investigated. Patients who were ≥18 years old in an ICU from January 2010 through June 2020, receiving mechanical ventilation, and fasting for >7 days, were selected from a Japanese medical claims database and divided, based on prescribed ILE during days from 4 to 7 of ICU admission, into 2 groups, no-lipid and with-lipid. Associations between the with-lipid group and in-hospital mortality, hospital readmission, and hospital LOS were evaluated relative to the no-lipid group. Regression analyses and the Cox proportional hazards model were used to calculate the odds ratios (OR) and regression coefficients, and hazard ratios (HR) were adjusted for patient characteristics and parenteral energy and amino acid doses. A total of 20,773 patients were evaluated. Adjusted OR and HR (95% confidence interval) for in-hospital mortality were 0.66 (0.62-0.71) and 0.68 (0.64-0.72), respectively, for the with-lipid group relative to the no-lipid group. No significant differences between the two groups were observed for hospital readmission or hospital LOS. The use of ILE for days 4 to 7 in PN prescribed for critically ill patients, who were in an ICU receiving mechanical ventilation and fasting for more than 7 days, was associated with a significant reduction in in-hospital mortality.

Association between caloric adequacy and short-term clinical outcomes in critically ill patients using a weight-based equation: Secondary analysis of a cluster-randomized controlled trial

Background

There is controversy over the optimal energy delivery in intensive care units (ICUs). In this study, we aimed to evaluate the association between different caloric adequacy assessed by a weight-based equation and short-term clinical outcomes in a cohort of critically ill patients.

Methods

This is a secondary analysis of a cluster-randomized controlled trial (N = 2,772). The energy requirement was estimated as 25 kcal/kg of body weight. The study subjects were divided into three groups according to their caloric adequacy as calculated by the mean energy delivered from days 3 to 7 of enrollment divided by the estimated energy requirements: (1) received &lt; 70% of energy requirement (hypocaloric), (2) received 70–100% of energy requirement (normocaloric), and (3) received &gt; 100% of energy requirement (hypercaloric). Cox proportional hazards models were used to analyze the association between caloric adequacy and 28-day mortality and time to discharge alive from the ICU.

Results

A total of 1,694 patients were included. Compared with normocaloric feeding, hypocaloric feeding significantly increased the risk of 28-day mortality (hazard ratio [HR] = 1.590, 95% confidence interval [CI]: 1.162–2.176, p = 0.004), while hypercaloric feeding did not. After controlling for potential confounders, the association remained valid (adjusted HR = 1.596, 95% CI: 1.150–2.215, p = 0.005). The caloric adequacy was not associated with time to discharge alive from the ICU in the unadjusted and the adjusted models.

Conclusion

Energy delivery below 70% of the estimated energy requirement during days 3–7 of critical illness is associated with 28-day mortality.

Clinical trial registration

[https://www.isrctn.com/ISRCTN12233792], identifier [ISRCTN12233792].

Comparison of the effects of different calorie amounts of enteral nutrition in hypercatabolism associated with ghrelin-POMC in endotoxemic rats

Background

Hypercatabolism often occurs in critically ill patients, and it increases infection rates and mortality in these patients. Enteral nutrition (EN) is commonly used in case of hypercatabolism. However, the effect of amount of calories in EN on hypercatabolism remains unexplored.

Objective

Here, we compared the effect of low-calorie, medium-calorie and high-calorie EN on hypercatabolism in the acute phase of endotoxemia, which is associated with gastrointestinal hormones and hypothalamic neuropeptide proopiomelanocortin (POMC).

Methods

Overall 84 adult male Sprague–Dawley rats were used for research. A set of rats were divided into 5 groups, Control (NS) and lipopolysaccharide (LPS) groups were fed a standard chow diet; LPS + L (LPS + 40 kcal/kg/day EN), LPS + M (LPS + 80 kcal/kg/day EN) and LPS + H (LPS + 120 kcal/kg/day EN) groups received EN through a gastric tube for 3 days. Another set of rats were used for parallel control experiment and divided into 5 groups: NS + F (saline + fasting) and LPS + F (LPS + fasting) groups were given no food, NS + L (saline + 40 kcal/kg/day EN), NS + M (saline + 80 kcal/kg/day EN) and NS + H (saline + 120 kcal/kg/day EN) groups received EN through a gastric tube for 3 days. Hypercatabolism was evaluated by assessing skeletal muscle protein synthesis and atrophy, insulin resistance, and corticosterone levels. Moreover, serum inflammatory factors, gastrointestinal hormones, hypothalamic ghrelin, growth hormone secretagogue receptor-1α, hypothalamic neuropeptide, and intestinal injury indicators were detected.

Results

Low-calorie EN effectively increased serum and hypothalamic ghrelin possibly due to slight intestinal barrier damage, thereby decreasing hypothalamic POMC expression; consequently, it alleviated rat insulin resistance, reduced blood cortisol levels and muscle atrophy, and improved the survival rate of rats in the acute phase of endotoxemia. Interestingly, with an increase in calories in enteral nutrition, the aforementioned effects did not increase.

Conclusions

Low-calorie EN could effectively increase gastrointestinal hormone ghrelin by reducing intestinal damage and suppressing POMC expression to ameliorate hypercatabolism when compared with medium-calorie and high-calorie EN. Therefore Low-calorie EN may be preferred for providing EN in the acute stage of endotoxemia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-022-00663-7.

Physician Compliance with Nutrition Support Team Recommendations: Effects on the Outcome of Treatment for Critically Ill Patients

Purpose: Attending physicians in Korea are aware of the existence of the Nutrition Support Team (NST), but even when the NST are consulted, compliance with their recommendations may be low. This study was performed to identify physicians’ compliance with the NST advice and how this affected the outcome of treatment for critically ill patients.Methods: This study was a retrospective observational study. Critically ill patients who were older than 18 years, younger than 90 years, and had been admitted and managed in the intensive care unit were selected for this study. Patients were assigned to either the compliance group or the non-compliance group according to physician compliance with the NST advice. Each group were compared using variables such as calorie supply, protein supply, laboratory findings, hospital stay, 30-day mortality, and survival rate.Results: The compliance group (81% of cases) was supplied with a significantly higher energy (1,146.36 ± 473.45 kcal vs. 832.45 ± 364.28 kcal, p < 0.01) and a significantly higher protein (55.00 ± 22.30 g/day vs. 42.98 ± 24.46 g/day, p = 0.04) compared with the non-compliance group. There was no significant difference in the basic demographics between groups, although the compliance group had a better outcome in the 30-day mortality rate (8% vs. 26%, p = 0.02), and in survival beyond 1 year (Crude model, hazard ratio: 2.42, CI: 1.11-5.29).Conclusion: Critically ill patients whose attending physician complied with the NST advice, received an increased energy intake and supply of protein which was positively associated with survival.

How much underfeeding can the critically ill adult patient tolerate?

Critical illness leads to significant metabolic alterations that should be considered when providing nutritional support. Findings from key randomized controlled trials (RCTs) indicate that underfeeding (<70% of energy expenditure [EE]) during the acute phase of critical illness (first 7 days of intensive care unit [ICU] admission) may not be harmful and could instead promote autophagy and prevent overfeeding in light of endogenous energy production. However, the optimal energy target during this period is unclear and full starvation is unlikely to be beneficial. There are limited data regarding the effects of prolonged underfeeding on clinical outcomes in critically ill patients, but recent studies show that oral food intake is suboptimal both in the ICU and following discharge to the acute care setting. It is hypothesized that provision of full nutrition (70-100% of EE) may be important in the recovery phase of critical illness (>7 days of ICU admission) for promoting recovery and rehabilitation; however, studies on nutritional intervention delivered from ICU admission through hospital discharge are needed. The aim of this review is to provide a narrative synthesis of the existing literature on metabolic alterations experienced during critical illness and the impact of underfeeding on clinical outcomes in the critically ill adult patient.

Early metabolic support for critically ill trauma patients: A prospective randomized controlled trial

BACKGROUND

There is a lack of consensus regarding the optimal nutritional support for trauma patients. We hypothesize that early postinjury metabolic support focusing on adequate protein would modify the metabolic signature and alter the inflammatory environment for critically ill trauma patients.

METHODS

We conducted a prospective randomized controlled pilot trial for adult patients admitted to the surgical intensive care unit following traumatic injury. Patients were randomized to receive early metabolic support (EMS) (peripheral amino acid infusions) or standard of care (enteral nutrition as soon as feasible). Routine laboratory assessments, nitrogen balance, cytokines, and metabolomic analyses were assessed at baseline and day 5 after intervention.

RESULTS

A total of 42 trauma patients were randomized into well-balanced groups with similar age (32 years), Injury Severity Score (25), and body mass index (27.4 kg/m2). Early metabolic support provided significantly more protein (1.43 g/kg vs. 0.35 g/kg; p < 0.0001) and more calories (12.6 kcal/kg vs. 7.5 g/kg; p = 0.0012) over the first 5 days as compared with the standard of care. Early metabolic support modified protein catabolism and synthesis as demonstrated by a larger median negative nitrogen balance (-16.3 g vs. -5.3 g; p = 0.03) and a unique metabolomic profile at day 5. The biochemical profile of patients who received EMS was defined by greater declines in circulating levels of stress hormone precursors and increased levels of amino acids. The inflammatory response following EMS resulted in a greater decrease in interleukin-1B (p = 0.02) and increase in soluble interleukin-6 receptor (p = 0.01) between baseline and day 5 as compared with the standard of care. The EMS group had a decreased length of stay (15 vs. 22 days) and decreased surgical intensive care unit length of stay (8 vs. 9 days); however, this disappeared after adjustment for Injury Severity Score in this small population.

CONCLUSIONS

Early metabolic support with amino acid is safe, modifies metabolism, and may downregulate the inflammatory state associated with significant trauma, warranting a larger trial to assess for improved outcomes.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level II.

U-Shape Relationship between Plasma Leucine Level and Mortality in the Intensive Care Unit

Patients in the intensive care unit (ICU) are at high risk of mortality which is not well predicted. Previous studies noted that leucine has prognostic value in a variety of diseases. This study investigated whether leucine concentration was a useful biomarker of metabolic and nutritional status and 6-month mortality in ICU. We recruited 454 subjects admitted to ICU (348 and 106 in the initiation and validation cohorts, respectively) with an acute physiology and chronic health evaluation (APACHE II) score ≥ 15. We measured plasma leucine concentrations, traditional biomarkers, and calculated APACHE II and sequential organ failure assessment (SOFA) scores. Leucine levels were weakly correlated with albumin, prealbumin, and transferrin levels (r = 0.30, 0.12, and 0.15, p = 0.001, 0.029, and 0.007, respectively). During follow-up, 116 (33.3%) patients died. Compared to patients with leucine levels between 109 and 174 μM, patients with leucine > 174 μM or <109 μM had a lower cumulative survival rate. Death was also associated with age, higher APACHE II and SOFA scores, C-reactive protein, and longer stays in the ICU, but with lower albumin, prealbumin, and transferrin. Patients with leucine levels > 174 μM had higher alanine aminotransferase levels, but no significant differences in other variables; patients with leucine levels < 109 μM had higher APACHE II and SOFA scores, higher incidence of using inotropic agents, longer ICU and hospital stays, but lower albumin and transferrin levels. Multivariable analysis demonstrated that leucine > 174 μM was an independent predictor of mortality, especially early mortality. However, among patients who stayed in ICU longer than two weeks, leucine < 109 μM was an independent predictor of mortality. In addition, leucine < 109 μM was associated with worse ventilator weaning profiles. These findings were similar in the validation cohort. Our study demonstrated a U-shape relationship between leucine levels and mortality rate in ICU.

Estimated versus measured energy expenditure in ventilated surgical-trauma critically Ill patients

BACKGROUND

The American and European guidelines recommend measuring resting energy expenditure (REE) using indirect calorimetry (IC). Predictive equations (PEs) are used to estimate REE, but there is limited evidence for their use in critically ill patients. The aim of this study is to evaluate the degree of agreement and accuracy between IC-REE and ten different PEs in mechanically ventilated surgical-trauma critically ill patients who met their estimated caloric requirement.

METHODS

IC-REE was retrospectively compared to PE-REE by 10 PEs. Degree of agreement between REE-PE and REE-IC was analyzed by the Bland-Altman test (BAt) and the Concordance Correlation Coefficient (CCC). The accuracy was calculated by the percentage of patients whose REE-PE values differ by up to ±10% in relation to REE-IC. All analyses were stratified by gender and BMI (< 25 vs ≥ 25).

RESULTS

104 patients were analyzed and the closest estimate to IC-REE was the modified Harris-Benedict equation (mHB) by the BAt with a mean difference of 49.2 overall, 61.6 for males, 28.5 for females, 67.5 for BMI < 25 and 42.5 for BMI ≥ 25. The overall CCC between the IC-REE and mHB was 0.652; 0.560 for males; 0.496 for females; 0.570 for BMI < 25; and 0.598 for BMI ≥ 25. Modified HB equation was the most accurate with overall accuracy of 44.2%.

CONCLUSIONS

Effectiveness of PEs for estimating REE of mechanically ventilated surgical-trauma critically ill patients is limited. Nonetheless, of all the 10 equations examined, the closest to IC measured REE was the modified HB equation. This article is protected by copyright. All rights reserved.

Safety of Using Enteral Nutrition Formulations Containing Dietary Fiber in Hospitalized Critical Care Patients: A Systematic Review and Meta-Analysis

Enteral nutrition (EN) is the preferred route of nutrition support for patients with critical illness undergoing intensive care. Experts in the field caution against using fiber during EN because of perceived adverse patient outcomes; however, a comprehensive assessment of this topic is not evident to date. In this systematic review and meta-analysis, we searched four databases from inception to April 20, 2020, for studies on adverse events or health outcomes associated with using EN formulations containing fiber in hospitalized adults with critical illness. Nineteen articles were included. Random-effects meta-analysis models showed significantly lower diarrhea scores for fiber groups compared with nonfiber groups (pooled mean difference: -2.78; 95% CI, -4.10 to -1.47) but mixed results for risk of diarrhea between groups, depending on measures used for diarrhea (Hart and Dobb scale, pooled risk ratio [RR]: 0.68; 95% CI, 0.45-1.02; other diarrhea scales, pooled RR: 0.42; 95% CI, 0.20-0.89). Models showed 39% lower risk of gastrointestinal (GI) complications overall for fiber compared with nonfiber groups (pooled RR: 0.61; 95% CI, 0.47-0.79) but no group differences for individual GI complications, mortality, and intensive care unit or hospital length of stay. Analyses stratified by soluble- or mixed-fiber interventions reduced heterogeneity in models but showed identical conclusions. EN formulas with fiber may help reduce incidence and severity of diarrhea and GI complications overall in critically ill patients, without increased risk of other adverse events. Bias among specific GI measures indicates more high-quality studies are needed to verify these conclusions.

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.

Overcoming challenges to enteral nutrition delivery in critical care

PURPOSE OF REVIEW

Existing data and all ICU nutrition guidelines emphasize enteral nutrition (EN) represents a primary therapy leading to both nutritional and non-nutritional benefits. Unfortunately, iatrogenic malnutrition and underfeeding is virtually ubiquitous in ICUs worldwide for prolonged periods post-ICU admission. Overcoming essential challenges to EN delivery requires addressing a range of real, and frequently propagated myths regarding EN delivery.

RECENT FINDINGS

Key recent data addresses perceived challenges to EN including: Adequately resuscitated patients on vasopressors can and likely should receive trophic early EN and this was recently associated with reduced mortality; Patients paralyzed with neuromuscular blocking agents can and should receive early EN as this was recently associated with reduced mortality/hospital length of stay; Proned patients can safely receive EN; All ICU nutrition delivery, including EN, should be objectively guided by indirect calorimetry (IC) measures. This is now possible with the new availability of a next-generation IC device.

SUMMARY

It is the essential implementation of this new evidence occurs to overcome real and perceived EN challenges. This data should lead to increased standardization/protocolization of ICU nutrition therapy to ensure personalized nutrition care delivering the right nutrition dose, in the right patient, at the right time to optimize clinical outcome.

Point-Counterpoint: Indirect Calorimetry Is Essential for Optimal Nutrition Therapy in the Intensive Care Unit

Iatrogenic malnutrition and underfeeding are ubiquitous in intensive care units (ICUs) worldwide for prolonged periods after ICU admission. A major driver leading to the lack of emphasis on timely ICU nutrition delivery is lack of objective data to guide nutrition care. If we are to ultimately overcome current fundamental challenges to effective ICU nutrition delivery, we must all adopt routine objective, longitudinal measurement of energy targets via indirect calorimetry (IC). Key evidence supporting the routine use of IC in the ICU includes (1) universal societal ICU nutrition guidelines recommending IC to determine energy requirements; (2) data showing predictive equations or body weight calculations that are consistently inaccurate and correlate poorly with measured energy expenditure, ultimately leading to routine overfeeding and underfeeding, which are both associated with poor ICU outcomes; (3) recent development and worldwide availability of a new validated, accurate, easy-to-use IC device; and (4) recent data in ICU patients with coronavirus disease 2019 (COVID-19) showing progressive hypermetabolism throughout ICU stay, emphasizing the inaccuracy of predictive equations and marked day-to-day variability in nutrition needs. Thus, given the availability of a new validated IC device, these findings emphasize that routine longitudinal IC measures should be considered the new standard of care for ICU and post-ICU nutrition delivery. As we would not deliver vasopressors without accurate blood pressure measurements, the ICU community is only likely to embrace an increased focus on the importance of early nutrition delivery when we can consistently provide objective IC measures to ensure personalized nutrition care delivers the right nutrition dose, in the right patient, at the right time to optimize clinical outcomes.

Full Versus Trophic Feeds in Critically Ill Adults with High and Low Nutritional Risk Scores: A Randomized Controlled Trial

Although energy intake might be associated with clinical outcomes in critically ill patients, it remains unclear whether full or trophic feeding is suitable for critically ill patients with high or low nutrition risk. We conducted a prospective study to determine which feeding energy intakes were associated with clinical outcomes in critically ill patients with high or low nutrition risk. This was an investigator-initiated, single center, single blind, randomized controlled trial. Critically ill patients were allocated to either high or low nutrition risk based on their Nutrition Risk in the Critically Ill score, and then randomized to receive either the full or the trophic feeding. The feeding procedure was administered for six days. No significant differences were observed in hospital, 14-day and 28-day mortalities, the length of ventilator dependency, or ICU and hospital stay among the four groups. There were no associations between energy and protein intakes and hospital, 14-day and 28-day mortalities in any of the four groups. However, protein intake was positively associated with the length of hospital stay and ventilator dependency in patients with low nutrition risk receiving trophic feeding. Full or trophic feeding in critically ill patients showed no associations with clinical outcomes, regardless of nutrition risk.

Physiologic Effects of Exogenous Dextrose in Murine Klebsiella pneumoniae Sepsis Vary by Route of Provision

Sepsis is characterized by a dysregulated immune response to infection. Nutrition is important in the care of septic patients, but the effects of specific nutrients on inflammation in sepsis are not well defined. Our prior work has shown benefits from early enteral dextrose infusion in a preclinical endotoxemia model of sepsis. In the current study, we extend our initial work to examine the effects of dextrose infusions, varying by route of administration, on inflammation and glycemic control in a more clinically relevant and translational model of Klebsiella pneumoniae (KP) bacteremia. Ten-week old C57BL6/J male mice (n = 31) underwent the implantation of indwelling vascular catheters, followed by inoculation with oropharyngeal KP. The mice were randomized 24 h after inoculation to (1) intravenous (IV) dextrose, (2) enteral dextrose, or (3) enteral saline (control) to study the effects on systemic inflammation, hemodynamics, and glycemic control. At 72 h, 77% of the control mice died, whereas IV dextrose induced 100% mortality, associated with increased inflammation, hyperglycemia, and hypotension. Enteral dextrose reduced mortality to 27%, promoted euglycemia, and reduced inflammation compared to IV dextrose. We conclude, in a bacteremic model of sepsis, that enteral (but not IV) dextrose administration is protective, suggesting that the route of nutrient support influences inflammation in sepsis.

Nutritional status of trauma patients hospitalized at surgical intensive care unit

Malnutrition results from a decrease or increase or imbalance of energy, protein and other nutrients, leading to measurable negative effects on body tissue, body shape, organ function and clinical status. Research shows that nutritional support is one of the necessary processes for survival of traumatic patient hospitalized at surgical intensive care unit. The purpose of this study is to evaluate the nutritional status of trauma patients hospitalized at surgical intensive care unit of Kowsar Hospital in Semnan, Iran. This cross-sectional descriptive study was performed on patients older than 18 years with head, neck and femur injuries. Initial data were collected using a checklist containing demographic information questions, designed from the Ministry of Health and Medical Education's Nutrition Screening Form, which was available in the Nutrition Assessment Forms and Guidelines for Hospitalized Patients Approved in 2013. The data were analyzed using Chi-square or Fisher's exact tests, paired t-test and Pearson coefficient. The confidence level was 95% and significance level was less than 0.05 in all tests. The amount of energy determined by the intensive care unit for the patients, with a significantly lower relationship than the amount of energy required by the patients for 24 hours, based on the Harris Benedict formula was (918.20±474.80 calories vs. 1535.76±243.73 calories, respectively and P-value˂0.001). The amount of protein determined by the intensive care unit for the patients for 24 hours, with a significantly relationship lower than the protein required for the patients for 24 hours, was (51.68±34.39 vs. 106.57±13.67, respectively, and P-value˂ 0.001). There was a statistically significant relationship between the age of the patients and energy (P˂0.001) and protein (P˂0.001) determined by the intensive care unit for the patients for 24 hours and energy (P˂0.001) and protein (P˂0.001) required for the patients for 24 hours. The results of this study showed that both the amount of energy and the amount of protein determined by the intensive care unit for trauma patients for less than 24 hours were lower than the required level; therefore, dietary modification for these patients is recommended.

Effect of high-protein nutrition in critically ill patients: A retrospective cohort study

BACKGROUND & AIMS

Early provision of a high-protein nutrition improves the prognosis of patients in intensive care units (ICUs). However, high protein intake increases blood urea nitrogen (BUN). No study has compared outcomes according to protein intake, and the clinical significance of changes in BUN (ΔBUN) in ICU patients is unclear. Here, we investigated the association of high protein intake with outcomes and BUN and assessed the clinical significance of ΔBUN.

METHODS

This was a single-center retrospective cohort study. Between 1 January 2016 and 30 September 2019, 295 ICU patients received enteral nutrition for at least 3 days while undergoing mechanical ventilation. After applying the exclusion criteria of an age of <18 years, gastrointestinal disease, maintenance dialysis, renal replacement therapy after admission, kidney transplantation, and death within 7 days of commencing enteral nutrition, 206 patients remained.

INTERVENTIONS

Participants were divided into those receiving >1.2 g/kg/day of protein (high-protein group; n = 111) and those receiving ≤1.2 g/kg/day of protein (non-high-protein group; n = 95). The groups were balanced by propensity score matching. The primary endpoint was 28-day mortality, and the secondary endpoints were 90-day mortality, length of ICU stay, number of ventilator-free days in the first 28 days, and ΔBUN.

RESULTS

The high-protein group had significantly lower 28- and 90-day mortality and significantly greater ΔBUN, including after propensity score matching. ΔBUN might not be associated with outcomes.

CONCLUSIONS

Provision of >1.2 g/kg/day of protein may be associated with lower mortality of tube-fed and mechanically ventilated patients. Furthermore, while high protein intake may be associated with higher BUN, these changes may not be adversely associated with outcomes.

Nutrition Support After Cardiac Surgery: Lessons Learned From a Prospective Study

The importance of postoperative nutrition support (NS) has been poorly recognized in cardiac surgery. In this population, we aim to describe the delivery of NS, factors affecting calorie/protein delivery and NS-associated morbidity. From January 2015 to January 2017, we prospectively observed all cardiac surgery patients at a single institution who could not take nutrition orally, requiring postoperative NS, either enteral or parenteral, for the duration of NS up to 14 days. We compared outcomes to patients without NS and examined NS indications, factors affecting its delivery and its associated complications. Nine percent of patients (232/2603) required NS for a total of 1938 NS-days. The most common indication was mechanical ventilation. NS met 69% of daily caloric needs. On days when tube feeds (TFs) were held (mean of 13 hours), this decreased to 43%, compared to 96% when TFs were not held (P < 0.001). The most common reason for holding TFs was procedures. When TFs were supplemented with parenteral nutrition (TFs + PN), 86% of daily caloric needs were met. Even on days when TFs were held, this only dropped to 77% (TFs + PN), compared to 36% (TFs-only). By multivariable logistic regression, elemental and semielemental formulas, TF volume, and postpyloric feeds increased the risk of diarrhea, occurring in 28% of patients and 18% of TF-days. In cardiac surgery patients given postoperative NS, mortality and morbidity were an order of magnitude higher than those able to be fed orally. Enteral feeding delivered approximately two-thirds of needs, but PN supplementation dramatically improved this. Diarrhea was common, associated with the postpyloric route, increasing TF volume, and nonintact formula.

Nutrition in Patients with Idiopathic Pulmonary Fibrosis: Critical Issues Analysis and Future Research Directions

In idiopathic pulmonary fibrosis (IPF), several factors may have a negative impact on the nutritional status, including an increased respiratory muscles load, release of inflammation mediators, the coexistence of hypoxemia, and physical inactivity. Nutritional abnormalities also have an impact on IPF clinical outcomes. Given the relevance of nutritional status in IPF patients, we sought to focus on some critical issues, highlighting what is known and what should be further learned about these issues. We revised scientific literature published between 1995 and August 2019 by searching on Medline/PubMed and EMBASE databases including observational and interventional studies. We conducted a narrative review on nutritional assessment in IPF, underlining the importance of nutritional evaluation not only in the diagnostic process, but also during follow-up. We also highlighted the need to keep a high level of attention on cardiovascular comorbidities. We also focused on current clinical treatment in IPF with Nintedanib and Pirfenidone and management of gastrointestinal adverse events, such as diarrhea, induced by these antifibrotic drugs. Finally, we concentrated on the importance of pulmonary rehabilitation program, including nutritional assessment, education and behavioral change, and psychological support among its essential components. More attention should be devoted to the assessment of the undernutrition and overnutrition, as well as of muscle strength and physical performance in IPF patients, taking also into account that an adequate clinical management of gastrointestinal complications makes IPF drug treatments more feasible.

Nutrition in Patients with Idiopathic Pulmonary Fibrosis: Critical Issues Analysis and Future Research Directions

In idiopathic pulmonary fibrosis (IPF), several factors may have a negative impact on the nutritional status, including an increased respiratory muscles load, release of inflammation mediators, the coexistence of hypoxemia, and physical inactivity. Nutritional abnormalities also have an impact on IPF clinical outcomes. Given the relevance of nutritional status in IPF patients, we sought to focus on some critical issues, highlighting what is known and what should be further learned about these issues. We revised scientific literature published between 1995 and August 2019 by searching on Medline/PubMed and EMBASE databases including observational and interventional studies. We conducted a narrative review on nutritional assessment in IPF, underlining the importance of nutritional evaluation not only in the diagnostic process, but also during follow-up. We also highlighted the need to keep a high level of attention on cardiovascular comorbidities. We also focused on current clinical treatment in IPF with Nintedanib and Pirfenidone and management of gastrointestinal adverse events, such as diarrhea, induced by these antifibrotic drugs. Finally, we concentrated on the importance of pulmonary rehabilitation program, including nutritional assessment, education and behavioral change, and psychological support among its essential components. More attention should be devoted to the assessment of the undernutrition and overnutrition, as well as of muscle strength and physical performance in IPF patients, taking also into account that an adequate clinical management of gastrointestinal complications makes IPF drug treatments more feasible.

The effects of an enteral nutrition feeding protocol on critically ill patients: A prospective multi-center, before-after study

PURPOSE

The aim of this study was to explore the effects of an enteral nutrition (EN) feeding protocol in critically ill patients.

METHODS

This was a prospective multi-center before-after study. We compared energy related and prognostic indicators between the control group (pre-implementation stage) and intervention group (post-implementation stage). The primary endpoint was the percentage of patients receiving EN within 7 days after ICU admission.

RESULTS

209 patients in the control group and 230 patients in the intervention group were enrolled. The implementation of the EN protocol increased the percentage of target energy reached from day 3 to day 7, and the difference between two groups reached statistical significance in day 6 (P = .01) and day 7 (P = .002). But it had no effects on proportion of patient receiving EN (P = .65) and start time of EN (P = .90). The protocol application might be associated with better hospital survival (89.1% vs 82.8%, P = .055) and reduce the incidence of EN related adverse (P = .004). There was no difference in ICU length of stay, duration of mechanical ventilation and ICU cost.

CONCLUSION

The implementation of the enteral feeding protocol is associated with improved energy intake and a decreased incidence of enteral nutrition related adverse events for critically ill patients, but it had no statistically beneficial effects on reducing the hospital mortality rate. Trial registration ClinicalTrials.gov, NCT02976155. Registered November 29, 2016- Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02976155.

Nutritional status of trauma patients hospitalized at surgical intensive care unit

Malnutrition results from a decrease or increase or imbalance of energy, protein and other nutrients, leading to measurable negative effects on body tissue, body shape, organ function and clinical status. Research shows that nutritional support is one of the necessary processes for survival of traumatic patient hospitalized at surgical intensive care unit. The purpose of this study is to evaluate the nutritional status of trauma patients hospitalized at surgical intensive care unit of Kowsar Hospital in Semnan, Iran. This cross-sectional descriptive study was performed on patients older than 18 years with head, neck and femur injuries. Initial data were collected using a checklist containing demographic information questions, designed from the Ministry of Health and Medical Education's Nutrition Screening Form, which was available in the Nutrition Assessment Forms and Guidelines for Hospitalized Patients Approved in 2013. The data were analyzed using Chi-square or Fisher's exact tests, paired t-test and Pearson coefficient. The confidence level was 95% and significance level was less than 0.05 in all tests. The amount of energy determined by the intensive care unit for the patients, with a significantly lower relationship than the amount of energy required by the patients for 24 hours, based on the Harris Benedict formula was (918.20±474.80 calories vs. 1535.76±243.73 calories, respectively and P-value˂0.001). The amount of protein determined by the intensive care unit for the patients for 24 hours, with a significantly relationship lower than the protein required for the patients for 24 hours, was (51.68±34.39 vs. 106.57±13.67, respectively, and P-value˂ 0.001). There was a statistically significant relationship between the age of the patients and energy (P˂0.001) and protein (P˂0.001) determined by the intensive care unit for the patients for 24 hours and energy (P˂0.001) and protein (P˂0.001) required for the patients for 24 hours. The results of this study showed that both the amount of energy and the amount of protein determined by the intensive care unit for trauma patients for less than 24 hours were lower than the required level; therefore, dietary modification for these patients is recommended.

Hypoenergetic feeding does not improve outcomes in critically ill patients with premorbid obesity: a post hoc analysis of a randomized controlled trial

Optimal energy goals for adult, obese critically ill surgical patients are unclear. To date, there has been little data comparing feeding regimens for obese and non-obese critically ill surgical patients and the effect on outcomes. The objective was to compare the effect of hypoenergetic and euenergetic feeding goals in critically ill obese patients on outcomes, including infection, intensive care unit length of stay, and mortality. We hypothesized that hypoenergetic feeding of patients with premorbid obesity (body mass index ≥ 30 kg•m^-2) during critical illness does not affect clinical outcomes. Post hoc analyses were performed on critically ill surgical patients enrolled in a randomized controlled trial. Patients were randomized to receive 25-30 kcal•kg^-1•d^-1 (105-126 kJ.kg^-1•d^-1, euenergetic) or 12.5-15 kcal•kg^-1•d^-1 (52-63 kJ.kg^-1 •d^-1, hypoenergetic), with equal protein allocation (1.5 g•kg^-1•d^-1). The effect of feeding regimen on outcomes in obese and nonobese patients were assessed. Of the 83 patients, 30 (36.1%) were obese (body mass index ≥ 30 kg•m^-2). Average energy intake differed based on feeding regimen (hypoenergetic: 982±61 vs euenergetic: 1338±92 kcal•d^-1, P = .02). Comparing obese and nonobese patients, there was no difference in the percentage acquiring an infection (66.7% [20/30] vs 77.4% [41/53], P = .29), intensive care unit length of stay (16.4±3.7 vs 14.3±0.9 days, P = .39), or mortality (10% [3/30] vs 7.6% [4/53], P = .7). Within the subset of obese patients, the percentage acquiring an infection (hypoenergetic: 78.9% [15/19] vs euenergetic: 45.5% [5/11], P = .11) was not affected by the feeding regimen. Within the subset of nonobese patients, there was a trend toward more infections in the euenergetic group (hypoenergetic: 63.6% [14/22] vs euenergetic: 87.1% [27/31], P = .05). Hypoenergetic feeding does not appear to affect clinical outcomes positively or negatively in critically ill patients with premorbid obesity.

3D kernel-density stochastic model for more personalized glycaemic control: development and in-silico validation

Background

The challenges of glycaemic control in critically ill patients have been debated for 20 years. While glycaemic control shows benefits inter- and intra-patient metabolic variability results in increased hypoglycaemia and glycaemic variability, both increasing morbidity and mortality. Hence, current recommendations for glycaemic control target higher glycaemic ranges, guided by the fear of harm. Lately, studies have proven the ability to provide safe, effective control for lower, normoglycaemic, ranges, using model-based computerised methods. Such methods usually identify patient-specific physiological parameters to personalize titration of insulin and/or nutrition. The Stochastic-Targeted (STAR) glycaemic control framework uses patient-specific insulin sensitivity and a stochastic model of its future variability to directly account for both inter- and intra-patient variability in a risk-based insulin-dosing approach.

Results

In this study, a more personalized and specific 3D version of the stochastic model used in STAR is compared to the current 2D stochastic model, both built using kernel-density estimation methods. Fivefold cross validation on 681 retrospective patient glycaemic control episodes, totalling over 65,000 h of control, is used to determine whether the 3D model better captures metabolic variability, and the potential gain in glycaemic outcome is assessed using validated virtual trials. Results show that the 3D stochastic model has similar forward predictive power, but provides significantly tighter, more patient-specific, prediction ranges, showing the 2D model over-conservative > 70% of the time. Virtual trial results show that overall glycaemic safety and performance are similar, but the 3D stochastic model reduced median blood glucose levels (6.3 [5.7, 7.0] vs. 6.2 [5.6, 6.9]) with a higher 61% vs. 56% of blood glucose within the 4.4–6.5 mmol/L range.

Conclusions

This improved performance is achieved with higher insulin rates and higher carbohydrate intake, but no loss in safety from hypoglycaemia. Thus, the 3D stochastic model developed better characterises patient-specific future insulin sensitivity dynamics, resulting in improved simulated glycaemic outcomes and a greater level of personalization in control. The results justify inclusion into ongoing clinical use of STAR.

Combination of High-Calorie Delivery and Organ Failure Increases Mortality Among Patients With Acute Respiratory Distress Syndrome

OBJECTIVES

Among critically ill patients, the benefits of nutrition support may vary depending on severity of organ dysfunction. The objective of the current article was to explore the relationship between organ failure and calories exposure with hospital mortality during the first week of acute respiratory distress syndrome.

DESIGN

Retrospective observational study.

SETTING

Single-center ICU.

PATIENTS

Adults admitted to the ICU with a diagnosis of acute respiratory distress syndrome.

INTERVENTIONS

Calorie delivery from enteral nutrition, parenteral nutrition, propofol, and dextrose containing fluids were collected for 7 days following intubation. Sequential Organ Failure Assessment score was calculated at ICU admit and for the same 7 days to describe organ dysfunction; four different Sequential Organ Failure Assessment variables were created 1) Sequential Organ Failure Assessment at ICU admit, 2) average Sequential Organ Failure Assessment for the first 7 days following intubation, 3) the highest Sequential Organ Failure Assessment for the first 7 days following intubation, and 4) change in Sequential Organ Failure Assessment from intubation to 7 days later.

MEASUREMENTS AND MAIN RESULTS

A total of 298 patients were included. Sequential Organ Failure Assessment at ICU admit, average Sequential Organ Failure Assessment for the first 7 days following intubation, highest Sequential Organ Failure Assessment for the first 7 days following intubation, change in Sequential Organ Failure Assessment from intubation to 7 days later, and calorie delivery the first 7 days following intubation were all associated with increased likelihood of mortality. Compared with patients with low organ failure and low-calorie delivery, those with high-calorie delivery and low organ failure, low-calorie delivery and high organ failure, and the combination of both high organ failure with high-calorie delivery were associated with an incremental increase in the likelihood or mortality.

CONCLUSIONS

Organ failure appears to modify the relationship between calorie exposure and ICU outcome. Additional research is needed to identify appropriate thresholds for safe calorie exposure with increased organ failure.

Metabolic Resuscitation Strategies to Prevent Organ Dysfunction in Sepsis

Significance: Sepsis is the main cause of death among patients admitted to the intensive care unit. As current treatment is limited to antimicrobial therapy and supportive care, mortality remains high, which warrants efforts to find novel therapies. Recent Advances: Mitochondrial dysfunction is emerging as a key process in the induction of organ dysfunction during sepsis, and metabolic resuscitation might reveal to be a novel cornerstone in the treatment of sepsis. Critical Issues: Here, we review novel strategies to maintain organ function in sepsis by precluding mitochondrial dysfunction by lowering energetic demand to allow preservation of adenosine triphosphate-levels, while reducing free radical generation. As the most common strategy to suppress metabolism, that is, cooling, does not reveal unequivocal beneficial effects and may even increase mortality, caloric restriction or modulation of energy-sensing pathways (i.e., sirtuins and AMP-activated protein kinase) may offer safe alternatives. Similar effects may be offered when mimicking hibernation by hydrogen sulfide (H₂S). In addition H₂S may also confer beneficial effects through upregulation of antioxidant mechanisms, similar to the other gasotransmitters nitric oxide and carbon monoxide, which display antioxidant and anti-inflammatory effects in sepsis. In addition, oxidative stress may be averted by systemic or mitochondria-targeted antioxidants, of which a wide range are able to lower inflammation, as well as reduce organ dysfunction and mortality from sepsis. Future Directions: Mitochondrial dysfunction plays a key role in the pathophysiology of sepsis. As a consequence, metabolic resuscitation might reveal to be a novel cornerstone in the treatment of sepsis.

Dietary Management of Blood Glucose in Medical Critically Ill Overweight and Obese Patients: An Open-Label Randomized Trial

BACKGROUND

Enteral nutrition (EN) increases hyperglycemia due to high carbohydrate concentrations while providing insufficient protein. The study tested whether an EN formula with very high-protein- and low-carbohydrate-facilitated glucose control delivered higher protein concentrations within a hypocaloric protocol.

METHODS

This was a multicenter, randomized, open-label clinical trial with parallel design in overweight/obese mechanically ventilated critically ill patients prescribed 1.5 g protein/kg ideal body weight/day. Patients received either an experimental very high-protein (37%) and low-carbohydrate (29%) or control high-protein (25%) and conventional-carbohydrate (45%) EN formula.

RESULTS

A prespecified interim analysis was performed after enrollment of 105 patients (52 experimental, 53 control). Protein and energy delivery for controls and experimental groups on days 1-5 were 1.2 ± 0.4 and 1.1 ± 0.3 g/kg ideal body weight/day (P = .83), and 18.2 ± 6.0 and 12.5 ± 3.7 kcals/kg ideal body weight/day (P < .0001), respectively. The combined rate of glucose events outside the range of >110 and ≤150 mg/dL were not different (P = .54, primary endpoint); thereby the trial was terminated. The mean blood glucose for the control and the experimental groups were 138 (-SD 108, +SD 177) and 126 (-SD 99, +SD 160) mg/dL (P = .004), respectively. Mean rate of glucose events >150 mg/dL decreased (Δ = -13%, P = .015), whereas that of 80-110 mg/dL increased (Δ = 14%, P = .0007). Insulin administration decreased 10.9% (95% CI, -22% to 0.1%; P = .048) in the experimental group relative to the controls. Glycemic events ≤80 mg/dL and rescue dextrose use were not different (P = .23 and P = .53).

CONCLUSIONS

A very high-protein and low-carbohydrate EN formula in a hypocaloric protocol reduces hyperglycemic events and insulin requirements while increasing glycemic events between 80-110 mg/dL.

Effect of Permissive Underfeeding with Intensive Insulin Therapy on MCP-1, sICAM-1, and TF in Critically Ill Patients

Purpose: This study examined the effect of permissive underfeeding compared to target feeding and intensive insulin therapy (IIT) compared to conventional insulin therapy (CIT) on the inflammatory mediators monocyte chemoattractant protein 1 (MCP-1), soluble intercellular adhesion molecule 1 (sICAM-1), and tissue factor (TF) in critically ill patients. Methodology: This was a substudy of a 2 × 2 factorial design randomized controlled trial in which intensive care unit (ICU) patients were randomized into permissive underfeeding compared to target feeding groups and into IIT compared to CIT groups (ISRCTN96294863). In this substudy, we included 91 patients with almost equal numbers across randomization groups. Blood samples were collected at baseline and at days 3, 5, and 7 of an ICU stay. Linear mixed models were used to assess the differences in MCP-1, sICAM-1, and TF across randomization groups over time. Results: Baseline characteristics were balanced across randomization groups. Daily caloric intake was significantly higher in the target feeding than in the permissive underfeeding groups (P-value < 0.01), and the daily insulin dose was significantly higher in the IIT than in the CIT groups (P-value < 0.01). MCP-1, sICAM-1, and TF did not show any significant difference between the randomization groups, while there was a time effect for MCP-1. Baseline sequential organ failure assessment (SOFA) score and platelets had a significant effect on sICAM-1 (P-value < 0.01). For TF, there was a significant association with age (P-value < 0.01). Conclusions: Although it has been previously demonstrated that insulin inhibits MCP-1, sICAM-1 in critically ill patients, and TF in non-critically ill patients, our study demonstrated that IIT in critically ill patients did not affect these inflammatory mediators. Similarly, caloric intake had a negligible effect on the inflammatory mediators studied.

Adequacy of enteral nutritional support in intensive care units does not affect the short- and long-term prognosis of mechanically ventilated patients: a pilot study

OBJECTIVE

To correlate short-term (duration of mechanical ventilation and length of intensive care unit stay) and long-term (functional capacity) clinical outcomes of patients who reached nutritional adequacy ≥ 70% of predicted in the first 72 hours of hospitalization in the intensive care unit.

METHODS

This was a prospective observational pilot study conducted in an 18-bed intensive care unit. A total of 100 mechanically ventilated patients receiving exclusive enteral nutritional support and receiving intensive care for more than 72 hours were included. Patients who never received enteral nutrition, those with spinal cord trauma, pregnant women, organ donors and cases of family refusal were excluded. The variables studied were nutritional adequacy ≥ 70% of predicted in the first 72 hours of hospitalization, length of intensive care unit stay, duration of mechanical ventilation and the ability to perform activities of daily living after 12 months, assessed via telephone contact using the Lawton Activities of Daily Living Scale.

RESULTS

The mean duration of mechanical ventilation was 18 ± 9 days, and the mean intensive care unit length of stay was 19 ± 8 days. Only 45% of the patients received more than 70% of the target nutrition in 72 hours. There was no association between nutritional adequacy and short-term (duration of mechanical ventilation, length of stay in the intensive care unit and mortality) or long-term (functional capacity and mortality) clinical outcomes.

CONCLUSION

Critically ill patients receiving caloric intake ≥ 70% in the first 72 hours of hospitalization did not present better outcomes in the short term or after 1 year.

Insufficient Nutrition and Mortality Risk in Septic Patients Admitted to ICU with a Focus on Immune Dysfunction

Immune dysfunction is seen both in sepsis patients and in those with malnutrition. This study aimed to determine whether insufficient nutrition and immune dysfunction have a synergistic effect on mortality in critically ill septic patients. We conducted a prospective observational study from adult sepsis patients admitted to intensive care units (ICUs) between August 2013 and June 2016. Baseline characteristics including age, gender, body mass index, NUTRIC, Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores were recorded. Immune dysfunction, defined by human leukocyte antigen DR (HLA-DR) expression, was tested at days 1, 3, and 7 of ICU admission. The study included 151 patients with sepsis who were admitted to the ICU. The 28-day survivors had higher day 7 caloric intakes (89% vs. 73%, p = 0.042) and higher day 1-HLA-DR expression (88.4 vs. 79.1, p = 0.045). The cut-off points of day 7 caloric intake and day 1-HLA-DR determined by operating characteristic curves were 65.1% and 87.2%, respectively. Immune dysfunction was defined as patients with day 1-HLA-DR < 87.2%. Insufficient nutrition had no influence on survival outcomes in patients with immune dysfunction. However, patients with insufficient nutrition had poor prognosis when they were immune competent. Insufficient nutrition and immune dysfunction did not have a synergistic effect on mortality in critically ill septic patients.

Role of Nutrition Support in Inflammatory Conditions

This review intends to summarize recent development on the potential nutrition implications of acute inflammation encountered during critical illness. Different aspects of the inflammatory response and their impact on nutrition management during critical illness will be discussed: the timing of the postinjury metabolic response, the integration of regulatory mechanisms involved in the metabolic response to stress, the oxidative stress, the metabolic and clinical consequences in terms of energy expenditure, use of energy, changes in body composition, and behavior.

Nutrition delivery, workload and performance in a model-based ICU glycaemic control system

BACKGROUND AND OBJECTIVE

Hyperglycaemia is commonplace in the adult intensive care unit (ICU), and has been associated with increased morbidity and mortality. Effective glycaemic control (GC) can reduce morbidity and mortality, but has proven difficult. STAR is a model-based GC protocol that uniquely maintains normoglycaemia by changing both insulin and nutrition interventions, and has been proven effective in controlling blood glucose (BG) in the ICU. However, most ICU GC protocols only change insulin interventions, making the variable nutrition aspect of STAR less clinically desirable. This paper compares the performance of STAR modulating only insulin, with three simpler alternative nutrition protocols in clinically evaluated virtual trials.

METHODS

Alternative nutrition protocols are fixed nutrition rate (100% caloric goal), CB (Cahill et al. best) stepped nutrition rate (60%, 80% and 100% caloric goal for the first 3 days of GC, and 100% thereafter) and SLQ (STAR lower quartile) stepped nutrition rate (65%, 75% and 85% caloric goal for the first 3 days of GC, and 85% thereafter). Each nutrition protocol is simulated with the STAR insulin protocol on a 221 patient virtual cohort, and GC performance, safety and total intervention workload are assessed.

RESULTS

All alternative nutrition protocols considerably reduced total intervention workload (14.6-19.8%) due to reduced numbers of nutrition changes. However, only the stepped nutrition protocols achieved similar GC performance to the current variable nutrition protocol. Of the two stepped nutrition protocols, the SLQ nutrition protocol also improved GC safety, almost halving the number of severe hypoglycaemic cases (5 vs. 9, P = 0.42).

CONCLUSIONS

Overall, the SLQ nutrition protocol was the best alternative to the current variable nutrition protocol, but either stepped nutrition protocol could be adapted by STAR to reduce workload and make it more clinically acceptable, while maintaining its proven performance and safety.

How long are burn patients really NPO in the perioperative period and can we effectively correct the caloric deficit using an enteral feeding "Catch-up" protocol?

OBJECTIVE

"NPO at midnight" is a standard preoperative practice intended to reduce aspiration risk but can result in prolonged feeding interruptions in critically ill burn patients. Postoperative hyperalimentation in the form of a "catch-up" tube feeding protocol is routine. A retrospective review of our perioperative fasting practices and "catch-up" enteral feeding protocols was performed.

METHODS

Patients admitted to the Burn ICU from July 1st, 2015 to August 31st, 2016 were reviewed. Patients who had a protected airway in place, prescribed enteral nutrition, and underwent surgery were included. The time from NPO to surgical start (NPO-SS), NPO to feeding restart (NPO-FR), and calories received/prescribed were quantified. The efficacy of a postoperative catch-up feeding protocol was analyzed.

RESULTS

There were 41 patients that fit inclusion criteria with some undergoing multiple surgeries, yielding 109 surgeries/discrete perioperative events. The average total body surface area burn (38.1±23.6%), age (38.8±20.1years), ICU days (45.0±37.3 days), and ventilator days (35.1±33.8 days) were calculated. Average fasting durations of NPO-SS and NPO-FR were 9.3±3.1 and 14.2±4.1h, respectively. The average caloric deficit to prescribed calories ratio during the NPO-SS and NPO-FR periods were 1154±629/3534±851kcal and 1765±928/3534±851kcal, respectively. A post-operative catch-up protocol completely compensated for perioperative caloric deficits 68.8% (22/32) of the time.

CONCLUSIONS

In critically ill burn patients, a preoperative fast resulted in an average loss of greater than 50% of prescribed calories on the day of surgery. Clinicians should re-evaluate the standard practice of making preoperative patients "NPO at midnight". An effective catch-up protocol can adequately reduce caloric deficits.

Prescribed hypocaloric nutrition support for critically-ill adults

BACKGROUND

There are controversies about the amount of calories and the type of nutritional support that should be given to critically-ill people. Several authors advocate the potential benefits of hypocaloric nutrition support, but the evidence is inconclusive.

OBJECTIVES

To assess the effects of prescribed hypocaloric nutrition support in comparison with standard nutrition support for critically-ill adults SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL, Cochrane Library), MEDLINE, Embase and LILACS (from inception to 20 June 2017) with a specific strategy for each database. We also assessed three websites, conference proceedings and reference lists, and contacted leaders in the field and the pharmaceutical industry for undetected/unpublished studies. There was no restriction by date, language or publication status.

SELECTION CRITERIA

We included randomized and quasi-randomized controlled trials comparing hypocaloric nutrition support to normo- or hypercaloric nutrition support or no nutrition support (e.g. fasting) in adults hospitalized in intensive care units (ICUs).

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We meta-analysed data for comparisons in which clinical heterogeneity was low. We conducted prespecified subgroup and sensitivity analyses, and post hoc analyses, including meta-regression. Our primary outcomes were: mortality (death occurred during the ICU and hospital stay, or 28- to 30-day all-cause mortality); length of stay (days stayed in the ICU and in the hospital); and Infectious complications. Secondary outcomes included: length of mechanical ventilation. We assessed the quality of evidence with GRADE.

MAIN RESULTS

We identified 15 trials, with a total of 3129 ICU participants from university-associated hospitals in the USA, Colombia, Saudi Arabia, Canada, Greece, Germany and Iran. There are two ongoing studies. Participants suffered from medical and surgical conditions, with a variety of inclusion criteria. Four studies used parenteral nutrition and nine studies used only enteral nutrition; it was unclear whether the remaining two used parenteral nutrition. Most of them could not achieve the proposed caloric targets, resulting in small differences in the administered calories between intervention and control groups. Most studies were funded by the US government or non-governmental associations, but three studies received funding from industry. Five studies did not specify their funding sources.The included studies suffered from important clinical and statistical heterogeneity. This heterogeneity did not allow us to report pooled estimates of the primary and secondary outcomes, so we have described them narratively.When comparing hypocaloric nutrition support with a control nutrition support, for hospital mortality (9 studies, 1775 participants), the risk ratios ranged from 0.23 to 5.54; for ICU mortality (4 studies, 1291 participants) the risk ratios ranged from 0.81 to 5.54, and for mortality at 30 days (7 studies, 2611 participants) the risk ratios ranged from 0.79 to 3.00. Most of these estimates included the null value. The quality of the evidence was very low due to unclear or high risk of bias, inconsistency and imprecision.Participants who received hypocaloric nutrition support compared to control nutrition support had a range of mean hospital lengths of stay of 15.70 days lower to 10.70 days higher (10 studies, 1677 participants), a range of mean ICU lengths of stay 11.00 days lower to 5.40 days higher (11 studies, 2942 participants) and a range of mean lengths of mechanical ventilation of 13.20 days lower to 8.36 days higher (12 studies, 3000 participants). The quality of the evidence for this outcome was very low due to unclear or high risk of bias in most studies, inconsistency and imprecision.The risk ratios for infectious complications (10 studies, 2804 participants) of each individual study ranged from 0.54 to 2.54. The quality of the evidence for this outcome was very low due to unclear or high risk of bias, inconsistency and imprecisionWe were not able to explain the causes of the observed heterogeneity using subgroup and sensitivity analyses or meta-regression.

AUTHORS' CONCLUSIONS

The included studies had substantial clinical heterogeneity. We found very low-quality evidence about the effects of prescribed hypocaloric nutrition support on mortality in hospital, in the ICU and at 30 days, as well as in length of hospital and ICU stay, infectious complications and the length of mechanical ventilation. For these outcomes there is uncertainty about the effects of prescribed hypocaloric nutrition, since the range of estimates includes both appreciable benefits and harms.Given these limitations, results must be interpreted with caution in the clinical field, considering the unclear balance of the risks and harms of this intervention. Future research addressing the clinical heterogeneity of participants and interventions, study limitations and sample size could clarify the effects of this intervention.

ICU Nurses' Perceived Barriers to Effective Enteral Nutrition Practices: A Multicenter Survey Study

BACKGROUND

Critically ill patients are hypermetabolic and have increased energy requirements, making nutritional support a vital intervention. In the Intensive Care Units, enteral nutrition is based on opinions rather than evidence-based practices. Therefore, there is a need to identify the barriers to evidence based practice protocols for enteral feeding of patients in Jordanian ICUs.

AIMS

To explore Jordanian ICU nurses' perceived barriers for enteral nutrition that hinders them from utilizing the recommended EN guidelines.

METHODS

A descriptive cross-sectional design was utilized using self-administered questionnaire. A total of 131 nurses participated from different hospitals representing different healthcare sectors in Jordan.

RESULTS

The five barriers subscales' means were almost equal ranging from 4.04 (Delivery of EN to the Patient) to 4.33 (ICU Resources) (out of 7). The most important barrier was "Not enough nursing staff to deliver adequate nutrition" (M=4.80, SD=1.81, 60%), followed by "Fear of adverse events due to aggressively feeding patients" (M= 4.59, SD=1.50, 56%). Although no significant differences in the mean barrier score were revealed, minimal significant differences were revealed that were distributed among different barrier subscales.

CONCLUSION

Participants moderately perceived barriers with more focus on insufficient resources in ICU and among healthcare providers. Such barriers are modifiable and manageable, making their identification and management crucial for optimal patient care. This study confirms that enteral nutrition is a multidisciplinary responsibility.

Volume-based feeding improves nutritional adequacy in surgical patients

BACKGROUND

Critically ill surgical patients often receive inadequate enteral nutrition using traditional rate-based feeding methods. An alternative strategy is volume-based feeding, in which feeding rates are adjusted to deliver a goal volume per day.

METHODS

This prospective quality improvement study in a single surgical, trauma, and burn ICU compared volume-based feeding to rate-based feeding in a before-and-after design. Outcomes included calories and protein delivered, length of stay, infection, and mortality.

RESULTS

A total of 50 patients received volume-based feeding and 49 rate-based feeding. The volume-based group received a higher proportion of goal calories (84.5% vs. 73.4%; p = 0.005) and protein (86.2% vs. 77.4%; p = 0.01), as well as increased total daily calories (1604 vs. 1356 kcal; p = 0.02). There was no difference in length of stay, mortality, aspiration, or gastrointestinal intolerance.

CONCLUSIONS

Volume-based feeding improved nutritional intake in critically ill surgical patients, although this study was underpowered to determine differences in clinical outcomes.

Autophagy and Its Implications Against Early Full Nutrition Support in Critical Illness

The timing, dose, and route of early nutrition support in critically ill patients have been highly controversial for years. Despite the association of a caloric deficit with adverse outcome, several recent large, randomized, controlled trials have demonstrated a prolongation of organ failure and increased muscle weakness with increasing doses of nutrition in the acute phase of critical illness. A potential explanation for the negative impact of early, full feeding on outcome is feeding-induced suppression of autophagy, a cellular repair process that is necessary to clear intracellular damage. Whether nutrition management in critically ill patients should be guided by its effects on autophagy is a topic of debate. Currently, however, autophagy cannot be monitored in clinical practice. Moreover, clinical management should be guided by high-quality randomized controlled trials, which currently do not support the use of early full nutrition support.

Nutrition delivery of a model-based ICU glycaemic control system

BACKGROUND

Hyperglycaemia is commonplace in the adult intensive care unit (ICU), associated with increased morbidity and mortality. Effective glycaemic control (GC) can reduce morbidity and mortality, but has proven difficult. STAR is a proven, effective model-based ICU GC protocol that uniquely maintains normo-glycaemia by changing both insulin and nutrition interventions to maximise nutrition in the context of GC in the 4.4-8.0 mmol/L range. Hence, the level of nutrition it provides is a time-varying estimate of the patient-specific ability to take up glucose.

METHODS

First, the clinical provision of nutrition by STAR in Christchurch Hospital, New Zealand (N = 221 Patients) is evaluated versus other ICUs, based on the Cahill et al. survey of 158 ICUs. Second, the inter- and intra- patient variation of nutrition delivery with STAR is analysed. Nutrition rates are in terms of percentage of caloric goal achieved.

RESULTS

Mean nutrition rates clinically achieved by STAR were significantly higher than the mean and best ICU surveyed, for the first 3 days of ICU stay. There was large inter-patient variation in nutrition rates achieved per day, which reduced overtime as patient-specific metabolic state stabilised. Median intra-patient variation was 12.9%; however, the interquartile range of the mean per-patient nutrition rates achieved was 74.3-98.2%, suggesting patients do not deviate much from their mean patient-specific nutrition rate. Thus, the ability to tolerate glucose intake varies significantly between, rather than within, patients.

CONCLUSIONS

Overall, STAR's protocol-driven changes in nutrition rate provide higher nutrition rates to hyperglycaemic patients than those of 158 ICUs from 20 countries. There is significant inter-patient variability between patients to tolerate and uptake glucose, where intra-patient variability over stay is much lower. Thus, a best nutrition rate is likely patient specific for patients requiring GC. More importantly, these overall outcomes show high nutrition delivery and safe, effective GC are not exclusive and that restricting nutrition for GC does not limit overall nutritional intake compared to other ICUs.

Early Exposure to Recommended Calorie Delivery in the Intensive Care Unit Is Associated With Increased Mortality in Patients With Acute Respiratory Distress Syndrome

BACKGROUND

The Intensive Nutrition in Acute Lung Injury: Clinical Trial (INTACT), designed to evaluate outcomes of calorie delivery from acute respiratory distress syndrome (ARDS) diagnosis through hospital discharge, was stopped due to higher mortality in the intervention group. Post hoc analysis found timing and dose of calorie delivery influenced mortality. The objective of this retrospective cohort study was to determine if early vs late calorie exposure changed the hazard of death among a larger sample of patients with ARDS.

METHODS

Adult patients who met the eligibility criteria for INTACT but did not participate were included. Daily calorie delivery was collected from the date INTACT eligibility was determined to extubation or death. Cox proportional hazards regression was used to model the relationship between hazard of hospital death with average calorie exposure received over increasing study days and after day 7.

RESULTS

A total of 298 patients were included; overall mortality was 33%. Among patients who remained intubated at 1 week (n = 202), higher kcal/kg received from intensive care unit (ICU) days 1-6 increased hazards of subsequent death on days 7+ (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.01-1.06); kcal/kg received after ICU day 7 decreased the hazards of death on day 7+ (HR, 0.53; 95% CI, 0.33-0.84).

CONCLUSIONS

Higher calorie exposure between ICU days 1 and 7 was associated with higher subsequent hazard of mortality, and provision of high-calorie exposure after day 8 decreased the hazards of death.

Controversies Surrounding Critical Care Nutrition: An Appraisal of Permissive Underfeeding, Protein, and Outcomes

Over the past few years, numerous studies have called into question the optimal dose, timing, composition, and advancement rate of nutrition during the early acute phase of critical illness. These studies suggest permissive underfeeding with slow advancement may be more beneficial than aggressive full feeding. These counterintuitive results were possibly explained by enhanced autophagy, less hyperglycemia, or prevention of refeeding syndrome. This review underscores the controversies surrounding permissive underfeeding, aims to answer whether permissive underfeeding is appropriate for all critically ill patients, describes the impact of optimal protein delivery on critical care outcomes, discusses nutrition risk, and cogitates on the impact of nutrition on critical care outcomes.

A prospective study of energy and protein intakes in critically ill patients

BACKGROUND & AIMS

Providing adequate and appropriate food and nutrients satisfying the patients' safe nutritional need is one of the most important care practices for critically ill patients (CIPs) in ICU settings, and is strongly related to the patients' safety.

METHODS

In this prospective cross-sectional study data were collected from a 52-bed medical intensive care unit on 777 consecutive patients in six different ICUs. The patients' weights and heights were measured based on ulna length, knee height, MAC, Calf C, and Wrist C. Also, patient weight change history was asked for. All currently in-use dietary supplements and formulas in the ICU settings were checked for their ingredients. The patients' nutritional need was calculated individually for the disease state based on dietary ESPEN guidelines.

RESULTS

Mean ICU and hospital stay duration was 14.45 ± 11.81 and 15.38 ± 11.88 days respectively. Mean energy and protein requirements in the target population were 1804.61 ± 201.76 Kcal/day and 77.94 ± 12.72 gr/day, respectively. Mean actual energy and protein intakes were 1052.75 ± 561.25 Kcal/day and 35.38 ± 23.19 gr/day, respectively. Satisfaction percents for mean energy and protein requirement in the total population were 58.34% (1052.75/1804.4) and 45.41% (35.38/77.9), respectively. In 21.4% and 4.4% of the studied group, energy and protein intakes were about 75-100% of the patients' actual need, respectively. Another data analysis for patients with over 10 days of inpatient time showed that only 14.2% of patients had energy intakes, and only 3.2% of them had protein intakes in the range of 75-100% of their requirements.

CONCLUSION

Results showed that energy and protein intakes in CIPs are low, disproportionate to their requirements. Therefore, actual dietary intake records, individual dietary requirement calculation, and individual dietary planning in relation with the patients' disease and stress should be considered. Such an accurate nutritional care process can promote patient safety.

Critical Care Nutrition: Where's the Evidence?

The surgical critically ill patient is subject to a variable and complex metabolic response, which has detrimental effects on immunity, wound healing, and preservation of lean body muscle. The concept of nutrition support has evolved into nutrition therapy, whereby the primary objectives are to prevent oxidative cell injury, modulate the immune response, and attenuate the metabolic response. This review outlines the metabolic response to critical illness, describes nutritional risk; reviews the evidence for the role, dose, and timing of enteral and parenteral nutrition, and reviews the evidence for immunonutrition in the surgical intensive care unit.