Frequency of under- and overfeeding in mechanically ventilated ICU patients: causes and possible consequences

Efficacy of Fiber-Enriched Versus Fiber-Free Enteral Feeds on Bowel Function of Non-Critically Ill Tube-Fed Adult Patients in Saudi Arabia-A Prospective Cohort Study

BACKGROUND

There is controversy regarding whether using fiber-enriched formula affects the incidence of diarrhea among enterally fed patients in our setting. Also, there is a lack of clinical studies about enterally fed patients' tolerance for feeding and the incidence of diarrhea among patients in the Middle East. This study aimed to assess fiber enrichment's efficacy in reducing post-enteral feeding bowel intolerance in non-critically ill patients.

METHODS

This was a prospective cohort study of 55 fiber-free (FF) and 119 fiber-enriched (FE) tube-fed adult patients admitted for five or more days with medical or surgical conditions. Data on patients' demographics, antibiotics and laxative medications, and gastrointestinal complications were collected. Absolute risk reduction (ARR), relative risk reduction (RRR), and relative risks (RR) were calculated to assess the efficacy of fiber enrichment in reducing post-enteral feeding bowel intolerance. Statistical significance was set at p ≤ 0.05.

RESULTS

The rate of diarrhea dropped from 54.5% for FF to 29% for FE groups, with an ARR of 25.1% (95% CI 24.6-25.6, p < 0.001) and an RRR of 64.1%, and RR was 0.54, reflecting a reduction in the rate of diarrhea by 46% after fiber enrichment. The rate of significant weight loss dropped from 45.5% without enrichment to only 26.9% with enrichment, with an ARR of 18.6% (95% CI: 18.0-19.2, p < 0.001) and RRR of 40.9%, and RR was 0.59, reflecting a 41% reduction in significant weight loss after fiber enrichment. After adjusting for some potential confounders, FF formula was a significant predictor of diarrhea (OR = 3.04, 95% CI 1.49-6.19, p = 0.002) and significant weight loss (OR = 2.37, 95% CI 1.16-4.84, p = 0.018) in tube feeding, while antibiotic intake was also a significant predictor of only diarrhea (OR = 2.68, 95% CI 1.12-6.38, p = 0.026).

CONCLUSIONS

This study demonstrated the beneficial effect of fiber supplementation in minimizing diarrhea in hospitalized patients receiving tube feeding. Antibiotic usage must be scrutinized and stopped if possible. Overall, the study provides compelling evidence supporting fiber-enriched enteral feeding, though further discussion on potential confounders and clinical applications would enhance its impact. Further, well-designed RCTs are needed to prove the efficacy of fiber-enriched feeds used in enteral tube feeding in non-critically ill patients.

An Overlooked Challenge: A Retrospective Audit of Overnutrition in Hospital Rehabilitation Wards

Background/Objective: Research shows that obesity has risen among rehabilitation patients. Despite this, nutrition care in subacute rehabilitation wards focuses primarily on preventing and treating protein-energy malnutrition. The continued provision of energy-dense meals during lengthy rehabilitation admissions may present a risk of overnutrition for some patients, which can adversely affect functional outcomes. However, overnutrition is not routinely monitored in practice. This study summarizes the initial findings of a multi-site investigation of overnutrition incidence across five rehabilitation wards to scope the need for future research. Methods: A retrospective audit was conducted, including all inpatients admitted over 3 months to the study wards with a complete dataset (total sample n = 199). Data were collected from the medical record and menu management system to determine overnutrition, defined as an average daily energy intake equal to or greater than 1000 kJ above estimated requirements and weight gain of equal to or greater than 1 kg over the admission. Results: The incidence of overnutrition in the total sample was 12.1%. Of those patients deemed at low risk of malnutrition (n = 124), 19.4% developed overnutrition during their rehabilitation admission. Those who developed overnutrition during their admission gained an average of 2.9 kg, with a mean excess energy intake of 2456 kJ/day above estimated requirements. They also consumed a high intake of discretionary items (mean of 3156 kJ/day). Conclusions: The findings suggest that further research is needed to investigate the etiology and impact of the overlooked problem of overnutrition in subacute rehabilitation settings. Future investigation is essential to ensure that the planning and delivery of subacute dietetic and food services meet the nutrition needs of patients in longer-stay inpatient settings.

Association of energy delivery with short-term survival in mechanically ventilated critically ill adult patients: a secondary analysis of the NEED trial

BACKGROUND AND AIMS

The optimal energy delivery for mechanically ventilated patients is controversial, particularly during the first week of ICU admission. This study aimed to investigate the association between different caloric adequacy and 28-day mortality in a cohort of critically ill adults on mechanical ventilation.

METHODS

This is a secondary analysis of a multicenter, cluster-randomized controlled trial. Eligible patients were divided into four quartiles (Q1-Q4) according to caloric adequacy calculated by the actual average daily energy delivery during the first seven days of ICU stay divided by energy requirement as a percentage. Cox proportional hazards models were used to examine the impact of different quartiles of caloric adequacy on 28-day mortality in the whole cohort and subgroups with different nutritional risk status at enrollment.

RESULTS

A total of 1587 patients were included in this study, with an overall 28-day mortality of 15.8%. The average caloric adequacy was 26.3 ± 11.9% (Q1), 52.5 ± 5.5% (Q2), 71.7 ± 6.4% (Q3), 107.0 ± 22.2% (Q4), respectively (p < 0.001 among quartiles). Compared with Q1, Q3 was associated with lower mortality in the unadjusted model (hazard ratio [HR] = 0.536; 95% confidence interval [CI], 0.375-0.767; P = 0.001) and adjusted model (adjusted HR = 0.508; 95% CI, 0.339-0.761; P = 0.001). This association remained valid in the subgroup of high nutritional risk patients (unadjusted HR = 0.387; 95% CI, 0.238-0.627; P < 0.001 and adjusted HR = 0.369; 95% CI, 0.216-0.630; P < 0.001, respectively), but not in those with low risk.

CONCLUSIONS

Energy delivery near the 70% energy requirements in the first week of ICU stay was associated with reduced 28-day mortality among mechanically ventilated critically ill patients, especially in patients with high nutrition risk at admission.

The Use of Parenteral Nutrition and Disparities in Its Allocation Following Traumatic Injury

INTRODUCTION

Severe traumatic injury requires rapid and extensive deployment of resources to save the lives of the critically injured. The sequelae of traumatic injuries frequently require extensive intervention obligating patients to a complicated recovery process devoid of meaningful nutrition. In this setting, parenteral nutrition (PN) is key in enabling appropriate wound healing, recovery, and rehabilitation. We sought to examine the use of PN in adult trauma management and to highlight any disparities in the utilization of PN in adult trauma patients.

METHODS

We queried the 2017-2019 Trauma Quality Improvement Program (TQIP) for adult patients (aged > 18 y) who sustained blunt or penetrating traumatic injuries and received PN as part of their hospitalization. We compared time to PN administration based on demographics. We then used a multivariable logistic regression model to identify factors associated with the use of PN. We hypothesized that PN would be less commonly employed in the uninsured and minority groups.

RESULTS

We identified 2,449,498 patients with sufficient data for analysis. Of these, 1831 patients were treated with PN. On univariate analysis, PN patients were more commonly male (74.7% PN versus 60.2% non-PN; P < 0.001). PN use was more frequent in the Black population (24.3% PN versus 15.5% non-PN; P < 0.001) and less frequent in the White population (72.7% PN versus 81.2% non-PN; P < 0.001). PN use was also much more common among patients covered by Medicaid. Penetrating trauma was over twice as common among PN recipients relative to non-PN patients (% PN versus % non-PN). PN patients had higher injury severity scores (ISSs), more intensive care unit days, longer hospitalizations, and increased mortality compared to non-PN patients. PN patients were half as likely to discharge home and twice as likely to discharge to a long-term care facility. Multivariable analysis including age, race, trauma mechanism, primary payer, and ISS, demonstrated an association of PN use with increasing age (OR 1.01, P < 0.001), cases of penetrating trauma (odds ratio [OR], 2.47; P < 0.001), and patients with high ISS (OR, 0.1.06; P < 0.001). There was decreased use in Uninsured patient (OR, 0.54; P < 0.001).

CONCLUSIONS

PN use following traumatic injury is rarely required. Patients treated with PN typically have a resource-intense hospital course. More severe injuries, penetrating trauma, and increased age are more likely to result in PN use. Variations in PN use are apparent based on insurance payer, further examination into allocation of hospital and intensive care resources, as it pertains to patient socioeconomic status, is warranted in light of these findings.

The metabolic effects of intermittent versus continuous feeding in critically ill patients

Intermittent (or bolus) feeding regimens in critically ill patients have been of increasing interest to clinicians and scientists. Changes in amino acid, fat and carbohydrate metabolites over time might yet deliver other benefits (e.g. modulation of the circadian rhythm and sleep, and impacts on ghrelin secretion, insulin resistance and autophagy). We set out to characterise these changes in metabolite concentration. The Intermittent versus Continuous Feeding in Critically Ill paitents study (NCT02358512) was an eight-centre single-blinded randomised controlled trial. Patients were randomised to received a continuous (control arm) or intermittent (6x/day, intervention arm) enteral feeding regimen. Blood samples were taken on trial days 1, 7 and 10 immediately before and 30 min after intermittent feeds, and at equivalent timepoints in the control arm. A pre-planned targeted metabolomic analysis was performend using Nuclear Resonance Spectroscopy. Five hundred and ninety four samples were analysed from 75 patients. A total of 24 amino acid-, 19 lipid based-, and 44 small molecule metabolite features. Across the main two axes of variation (40-60% and 6-8% of variance), no broad patterns distinguished between intermittent or continuous feeding arms, across intra-day sampling times or over the 10 days from initial ICU admission. Logfold decreases in abundance were seen in metabolites related to amino acids (Glutamine - 0.682; Alanine - 0.594), ketone body metabolism (Acetone - 0.64; 3-Hydroxybutyric Acid - 0.632; Acetonacetic Acid - 0.586), fatty acid (carnitine - 0.509) and carbohydrate metabolism ( Maltose - 0.510; Citric Acid - 0.485). 2-3 Butanediol, a by-product of sugar-fermenting microbial metabolism also decreased (- 0.489). No correlation was seen with change in quadriceps muscle mass for any of the 20 metabolites varying with time (all p > 0.05). Increasing severity of organ failure was related to increasing ketone body metabolism (3 Hydroxybutyric Acid-1 and - 3; p = 0.056 and p = 0.014), carnitine deficiency (p = 0.002) and alanine abundancy (p - 0.005). A 6-times a day intermittent feeding regimen did not alter metabolite patterns across time compared to continuous feeding in critically ill patients, either within a 24 h period or across 10 days of intervention. Future research on intermittent feeding regimens should focus on clinical process benefits, or extended gut rest and fasting.

Potentials and Challenges of Pervasive Sensing in the Intensive Care Unit

Patients in critical care settings often require continuous and multifaceted monitoring. However, current clinical monitoring practices fail to capture important functional and behavioral indices such as mobility or agitation. Recent advances in non-invasive sensing technology, high throughput computing, and deep learning techniques are expected to transform the existing patient monitoring paradigm by enabling and streamlining granular and continuous monitoring of these crucial critical care measures. In this review, we highlight current approaches to pervasive sensing in critical care and identify limitations, future challenges, and opportunities in this emerging field.

Palestinian nurses' knowledge, attitudes, and practices regarding enteral nutrition: Cross-sectional study

BACKGROUND

Enteral nutrition support plays a key role in minimizing malnutrition in critically-ill patients, and its provision is originally a nurse's responsibility. Thus, nurses need to have a sufficient knowledge and a positive attitude with regard to enteral nutrition. In Palestine, literature regarding nurses' knowledge, practices, and attitudes of enteral nutrition is rare.

OBJECTIVE

This study aimed to investigate Palestinian nurses' knowledge, practices, and attitudes regarding enteral nutrition.

METHOD

Interview based pre-tested questionnaire was used during data collection procedure. Cronbach Alpha was also used to determine the reliability of knowledge, attitude and practice questionnaire. Descriptive statistics, independent t-test, and ANOVA were performed.

RESULTS

A total of 325 registered nurses were involved in the final analysis. The mean of the knowledge score is (9.6 ± 2.8) out of 20. It was confirmed that sociodemographic characteristics has no influence on nutrition knowledge score among nurses. The findings also reveal that certain aspects of enteral nutrition practices were consistent with the current guidelines such as flushing the tube and backrest elevation. On the other hand, certain practices showed inconsistency and differences with international guidelines such as checking gastric residual volume. Results also showed that nurses attitudes were positive towards enteral nutrition.

CONCLUSION

It was found that nurses' have inadequate knowledge regarding enteral nutrition. The findings also showed that enteral nutrition practices among nurses were somewhat incongruent with best current evidence. However, it was noted that they have positive attitudes towards enteral nutrition. Promoting research utilization is highly needed as well as establishing evidence-based guidelines.

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.

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

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

Practical Considerations for Ketogenic Diet in Adults With Super-Refractory Status Epilepticus

Purpose of Review

Ketogenic diet therapy can be used as an adjuvant treatment of super-refractory status epilepticus (SRSE). However, the drug and metabolic interactions with concomitant treatments present a challenge for clinicians. In this review, we focus on the practical considerations of implementing ketogenic dietary therapy in the acute setting, including the dietary composition, potential drug-diet interactions, and monitoring during ketogenic treatment.

Recent Findings

This report describes the ketogenic diet therapy protocol implemented for the treatment of SRSE and a review of the current evidence to support clinical practice.

Summary

The control of SRSE is critical in reducing morbidity and mortality. There is emerging evidence that ketogenic diet may be a safe and effective treatment option for these patients.

The relationship of the geriatric nutritional risk index to mortality and length of stay in elderly patients with acute respiratory failure: A retrospective cohort study

BACKGROUND

Elderly people with acute respiratory failure (ARF) have prolonged length of hospital stay (LOS) and high mortality rates. Malnutrition is negatively correlated with these LOS and mortality. However, no tools have been used to detect the risk of malnutrition and assist in designing nutritional support for these patients. The geriatric nutritional risk index (GNRI) is reported as a novel tool for evaluating the risk of malnutrition. The aim of this study is to explore the relationship of the GNRI score with mortality and LOS in elderly patients with ARF.

METHODS

Data of elderly patients diagnosed with ARF were retrieved from the Medical Information Mart for Intensive Care III (MIMIC-III) database. A total of 1250 patients were divided into two groups based on their GNRI score: the malnutrition risk group (GNRI ≤ 98) and no risk group (GNRI > 98). The primary endpoints of this study were hospital mortality and hospital LOS.

RESULTS

The higher GNRI score was associated with lower hospital mortality and shorter hospital LOS. Odds ratio (OR) for hospital mortality of patients with nutritional risk (GNRI ≤ 98) was 1.264 (95% CI:1.067-1.497) in the adjusted model. Patients with GNRI ≤98 had longer hospital LOS (adjusted OR: 1.142, 95%CI: 1.044-1.250) compared with those with GNRI > 98. Subgroup analysis showed that higher GNRI was only significantly associated with lower hospital mortality in the patients that did not undergo mechanical ventilator (MV) treatment (adjusted OR: 0.985, 95% CI: 0.977-0.992, P < 0.01). Kaplan-Meier curve analysis showed that the 90-day survival was significantly lower in the group with nutrition risk (GNRI≤98) compared with the no risk group (GNRI > 98, p < 0.05).

CONCLUSION

These findings imply that GNRI is a useful prognostic tool in elderly patients with ARF.

Overfeeding and obesity in young children with positive pressure ventilation via tracheostomy following cardiac surgery

OBJECTIVES

Infants with CHD requiring positive pressure ventilation via tracheostomy are especially vulnerable to malnutrition following cardiac surgery. Current post-operative feeding recommendations may overestimate the caloric needs.

DESIGN

We retrospectively studied infants requiring tracheostomy after cardiac surgery. Anthropometric and nutritional data were collected, including caloric goals, weight-for-age z score, length-for-age z score, and weight-for-length z score. Changes in anthropometrics over time were compared to ascertain the impact of nutritional interventions. Data were shown as mean ± standard deviation.

RESULTS

Nineteen infants with CHD required tracheostomy at 160 ± 109 days (7-364 days), 13 had reparative surgery, and 6 had palliative surgery for single ventricle. The indications for tracheostomy consisted of airway abnormality/obstruction (n = 13), chronic respiratory failure (n = 7), and/or vocal cord paresis (n = 2). Initial maintenance nutritional target was set at 100-130 cal/kg per day. Fourteen patients (73.7%) became obese (maximum weight-for-length z score: 2.59 ± 0.47) under tracheostomy and gastrostomy feeding, whereas five patients did not (weight-for-length z score: 0.2 ± 0.83). Eight obese patients (weight-for-length z score: 2.44 ± 0.85) showed effective reduction of obesity within 6 months (weight-for-length z score: 0.10 ± 0.20; p < 0.05 compared with pre-adjustment) after appropriate feeding adjustment (40-90 cal/kg per day). Overall mortality was high (31.6%) in this population.

CONCLUSION

Standard nutritional management resulted in overfeeding and obesity in young children with CHD requiring positive pressure ventilation via tracheostomy. Optimal nutritional management in this high-risk population requires close individualised management by multidisciplinary teams.

First international meeting of early career investigators: Current opportunities, challenges and horizon in critical care nutrition research

BACKGROUND

Appropriate nutritional support is a key component of care for critically ill patients. While malnutrition increases complications, impacting long term outcomes and healthcare-related costs, uncertainties persist regarding optimal provision of nutritional support in this setting.

METHODS

An international group of healthcare providers (HCPs) from critical care specialties and nutrition researchers convened to identify knowledge gaps and learnings from studies in critical care nutrition. Clinical research needs were identified in order to better inform future nutrition practices.

RESULTS

Challenges in critical care nutrition arise, in part, from inconsistent outcomes in several large-scale studies regarding the optimal amount of calories and protein to prescribe, the optimal time to initiate nutritional support and the role of parental nutrition to support critically ill patients. Furthermore, there is uncertainty on how best to identify patients at nutritional risk, and the appropriate outcome measures for ICU nutrition studies. Given HCPs have a suboptimal evidence base to inform the nutritional management of critically ill patients, further well-designed clinical trials capturing clinically relevant endpoints are needed to address these knowledge gaps.

CONCLUSIONS

The identified aspects for future research could be addressed in studies designed and conducted in collaboration with an international team of interdisciplinary nutrition experts. The aim of this collaboration is to address the unmet need for robust clinical data needed to develop high-quality evidence-based nutritional intervention recommendations to better inform the future management of critically ill patients.

Nutritional adequacy in critically ill patients: Result of PNSI study

BACKGROUND & AIMS

Critically ill patients are provided with the intensive care medicine to prevent further complications, including malnutrition, disease progression, and even death. This study was intended to assess nutritional support and its' efficacy in the Intensive Care Units (ICUs) of Iran.

METHODS

This cross-sectional study assessed 50 ICU's patients out of 25 hospitals in the 10 major regions of Iran's health system and was performed using the multistage cluster sampling design. The data were collected from patient's medical records, ICU nursing sheets, patients or their relatives from 2017 to 2018. Nutritional status was investigated by modified NUTRIC score and food frequency checklist.

RESULTS

This study included 1321 ICU patients with the mean age of 54.8 ± 19.97 years, mean mNUTRIC score of 3.4 ± 2.14, and malnutrition rate of 32.6%. The mean time of first feeding was the second day and most of patients (66%) received nutrition support, mainly through enteral (57.2%) or oral (37%) route during ICU stay. The patients received 59.2 ± 37.78 percent of required calorie and 55.5 ± 30.04 percent of required protein. Adequate intake of energy and protein was provided for 16.2% and 10.7% of the patients, respectively. The result of regression analysis showed that the odds ratio of mNUTRIC score was 0.85 (95% confidence interval [CI] = 0.74-0.98) and APACHE II was 0.92 (95%CI = 0.89-0.95) for the prediction of energy deficiency. Nutrition intake was significantly different from patient's nutritional requirements both in terms of energy (p < 0.001) and protein (p < 0.001). Also, mean mNUTRIC score varied notably (p = 0.011) with changing in energy intake, defined as underfeeding, adequate feeding, and overfeeding.

CONCLUSION

The present findings shown that, provided nutritional care for ICU patients is not adequate for their requirements and nutritional status.

Metabolic and Immunological Effects of Intermittent Fasting on a Ketogenic Diet Containing Medium-Chain Triglycerides in Healthy Dogs

In several species, intermittent fasting (IF) has been shown to have beneficial effects, including delayed aging, increased lifespan, increased insulin sensitivity, reduced ischemic tissue damage, delayed onset of neurodegenerative disease and improved neuronal repair following injury. However, the metabolic and immunological effects of IF have not been well-established in dogs. The aim of this study was to examine the effects of a 48 h IF regimen using a low fat and a high fat diet in healthy dogs by quantifying the metabolic, hormonal, and immunological changes. We hypothesized that IF dogs would have higher blood ketone and ghrelin concentrations, lower blood leptin, insulin and glucose concentrations, and signs of immunosuppression compared to dogs eating daily. Ten healthy adult dogs were randomized into three group and underwent three feeding regimes in a 3 × 3 Latin square design: twice a day feeding on a low fat (23% energy from fat; LF) diet, 48 h fasting on a low fat diet, and 48 h fasting on a high fat enriched with medium-chain triglycerides (68% energy from fat; HF) diet. Body weight, food intake, activity, blood glucose, β-hydroxybutyrate, leptin, ghrelin, and insulin were measured. Lymphocyte proliferation and neutrophil/macrophage phagocytosis and respiratory burst were measured as markers of immune function. Nuclear magnetic resonance spectroscopy was used to relatively quantify plasma metabolites. When the dogs were IF on a HF diet, they had the highest concentration of blood ketones (mean 0.061 mmol/L, SD 0.024), whereas they had the lowest concentration (mean 0.018 mmol/L, SD 0.004) when fed daily. Blood glucose and insulin concentrations were lower in IF dogs on a HF diet compared to daily feeding or IF on a LF diet. There was an increase in plasma β-hydroxybutyrate concentrations, and a reduction in glucose and insulin concentrations when dogs were IF on a HF diet. There was only a decline in the immune parameters studied when the dogs were IF on a LF diet, which was not seen when on the HF diet. The results of this study indicate the potential of IF to be further investigated as a potential beneficial feeding regime for dogs.

Measuring nutrition-related outcomes in a cohort of multi-trauma patients following intensive care unit discharge

BACKGROUND

Functional recovery is an important outcome for those who survive critical illness. The present study aimed to assess nutrition provision and nutrition-related outcomes in a multi-trauma cohort following intensive care unit (ICU) discharge.

METHODS

The present study investigated a prospective cohort of patients discharged from an ICU, who had been admitted because of major trauma and required mechanical ventilation for at least 48 h. Nutrition-related outcomes, including body weight, quadriceps muscle layer thickness (QMLT), handgrip strength and subjective global assessment, were recorded on ICU discharge, days 5-7 post-ICU discharge and then weekly until hospital discharge. Nutrition intake was recorded for 5 days post-ICU discharge. Unless otherwise stated, data are presented as the mean (SD).

RESULTS

Twenty-eight patients [75% males, 55 (22.5) years] were included. Intake met 64% (28%) of estimated energy and 72% (32%) of protein requirements over the 5 days post-ICU discharge, which was similar to over the ICU admission. From ICU admission to hospital discharge, the mean reduction in weight was 4.2 kg (95% confidence interval = 2.2-6.3, P < 0.001) and after ICU discharge, the mean reduction in weight and QMLT was 2.6 kg (95% confidence interval = 1.0-4.2, P = 0.004) and 0.23 cm (95% confidence interval = 0.06-0.4, P = 0.01), respectively.

CONCLUSIONS

Patients received less energy and protein than estimated requirements after ICU discharge. Weight loss and reduction in QMLT also occurred during this period.

Clinical Sequelae From Overfeeding in Enterally Fed Critically Ill Adults: Where Is the Evidence?

Enteral energy delivery above requirements (overfeeding) is believed to cause adverse effects during critical illness, but the literature supporting this is limited. We aimed to quantify the reported frequency and clinical sequelae of energy overfeeding with enterally delivered nutrition in critically ill adult patients. A systematic search of MEDLINE, EMBASE, and CINAHL from conception to November 28, 2018, identified clinical studies of nutrition interventions in enterally fed critically ill adults that reported overfeeding in 1 or more study arms. Overfeeding was defined as energy delivery > 2000 kcal/d, > 25 kcal/kg/d, or ≥ 110% of energy prescription. Data were extracted on methodology, demographics, prescribed and delivered nutrition, clinical variables, and predefined outcomes. Cochrane "Risk of Bias" tool was used to assess the quality of randomized controlled trials (RCTs). Eighteen studies were included, of which 10 were randomized (n = 4386 patients) and 8 were nonrandomized (n = 223). Only 4 studies reported a separation in energy delivery between treatment groups whereby 1 arm met the definition of overfeeding, which reported no between-group differences in mortality, infectious complications, or ventilatory support. Overfeeding was associated with increased insulin administration (median 3 [interquartile range: 0-41.8] vs 0 [0-30.6] units/d) and upper-gastrointestinal intolerance in 1 large RCT and with duration of antimicrobial therapy in a small RCT. There are limited high-quality data to determine the impact of energy overfeeding of critically ill patients by the enteral route; however, based on available evidence, overfeeding does not appear to affect mortality or other important clinical outcomes.

Interprofessional Care and Teamwork in the ICU

OBJECTIVES

We describe the importance of interprofessional care in modern critical care medicine. This review highlights the essential roles played by specific members of the interprofessional care team, including patients and family members, and discusses quality improvement initiatives that require interprofessional collaboration for success.

DATA SOURCES

Studies were identified through MEDLINE search using a variety of search phrases related to interprofessional care, critical care provider types, and quality improvement initiatives. Additional articles were identified through a review of the reference lists of identified articles.

STUDY SELECTION

Original articles, review articles, and systematic reviews were considered.

DATA EXTRACTION

Manuscripts were selected for inclusion based on expert opinion of well-designed or key studies and review articles.

DATA SYNTHESIS

"Interprofessional care" refers to care provided by a team of healthcare professionals with overlapping expertise and an appreciation for the unique contribution of other team members as partners in achieving a common goal. A robust body of data supports improvement in patient-level outcomes when care is provided by an interprofessional team. Critical care nurses, advanced practice providers, pharmacists, respiratory care practitioners, rehabilitation specialists, dieticians, social workers, case managers, spiritual care providers, intensivists, and nonintensivist physicians each provide unique expertise and perspectives to patient care, and therefore play an important role in a team that must address the diverse needs of patients and families in the ICU. Engaging patients and families as partners in their healthcare is also critical. Many important ICU quality improvement initiatives require an interprofessional approach, including Awakening and Breathing Coordination, Delirium, Early Exercise/Mobility, and Family Empowerment bundle implementation, interprofessional rounding practices, unit-based quality improvement initiatives, Patient and Family Advisory Councils, end-of-life care, coordinated sedation awakening and spontaneous breathing trials, intrahospital transport, and transitions of care.

CONCLUSIONS

A robust body of evidence supports an interprofessional approach as a key component in the provision of high-quality critical care to patients of increasing complexity and with increasingly diverse needs.

Phenylalanine- and leucine-defined metabolic types identify high mortality risk in patients with severe infection

OBJECTIVE

To investigate the prognostic value of phenylalanine and leucine in patients with severe infection.

METHODS

Ninety-three patients with infection who had a quick Sequential Organ Failure Assessment (qSOFA) score ≥2 were enrolled. Plasma phenylalanine, leucine, albumin, C-reactive protein, pre-albumin, and transferrin were measured and the SOFA score at enrollment was calculated after hospitalization.

RESULTS

During the 3-month follow-up, 30 (32.3%) patients died. Death was associated with higher SOFA scores, a higher incidence of bacteremia and admission to the intensive care unit, higher C-reactive protein and phenylalanine levels, worse kidney function, and lower pre-albumin and transferrin levels. Patients were categorized into three groups: high-risk type 1 (phenylalanine ≥84μM), high-risk type 2 (phenylalanine <84μM and leucine <93μM), and low-risk (other). Compared to the low-risk type patients, high-risk type 1 and 2 patients had higher mortality rates (hazard ratio 10.1 (95% CI 2.33-43.5) and hazard ratio 5.56 (95% CI 1.22-25.4), respectively). Type 1 patients had higher SOFA scores, a higher incidence of admission to the intensive care unit, and higher C-reactive protein and leucine levels. Type 2 patients had lower albumin and hemoglobin levels. Multivariable analysis showed that both high-risk types were independent predictors of death.

CONCLUSIONS

Phenylalanine- and leucine-defined risk classifications provide metabolic information with prognostic value for patients with severe infection.

Enteral Nutrition in the Mechanically Ventilated Patient

Mechanically ventilated patients are unable to take food orally and therefore are dependent on enteral nutrition for provision of both energy and protein requirements. Enteral nutrition is supportive therapy and may impact patient outcomes in the intensive care unit. Early enteral nutrition has been shown to decrease complications and hospital length of stay and improve the prognosis at discharge. Nutrition support is unique for patients on mechanical ventilation and, as recently published literature shows, should be tailored to the individuals' underlying pathology. This review will discuss the most current literature and recommendations for enteral nutrition in patients receiving mechanical ventilation.

Prediction of Prolonged ICU Stay in Cardiac Surgery Patients as a Useful Method to Identify Nutrition Risk in Cardiac Surgery Patients: A Post Hoc Analysis of a Prospective Observational Study

BACKGROUND

Cardiovascular surgery patients with a prolonged intensive care unit (ICU) stay may benefit most from early nutrition support. Using established scoring systems for nutrition assessment and operative risk stratification, we aimed to develop a model to predict a prolonged ICU stay ≥5 days in order to identify patients who will benefit from early nutrition interventions.

METHODS

This is a retrospective analysis of a prospective observational study of patients undergoing elective valvular, coronary artery bypass grafting, or combined cardiac surgery. The nutrition risk was assessed by well-established screening tools. Patients' preoperative EuroSCORE (European System for Cardiac Operative Risk Evaluation), primary disease, and intraoperative cardiopulmonary bypass (CPB) time were included as independent variables in a multivariate logistic regression analysis to predict a prolonged ICU stay (>4 days).

RESULTS

The number of cardiac surgery patients included was 1193. Multivariate analysis revealed that for prediction of ICU stay >4 days, both Nutritional Risk Screening 2002 (area under the curve (AUC): 0.716, P = .020) and Mini Nutritional Assessment (MNA) score (AUC: 0.715, P = .037) were significant, whereas for prediction of ICU stay >5 days, only the MNA score showed significant results (AUC: 0.762, P = .011).

CONCLUSION

Present data provide first evidence about the combined use of EuroSCORE, primary disease, CPB time, and nutrition risk screening tools for prediction of prolonged ICU stay in cardiac surgery patients. If prospectively evaluated in adequately designed studies, this model may help to identify patients with prolonged ICU stay to initiate early postoperative nutrition therapy and thus, facilitate an enhanced recovery.

Intestinal failure in adults: Recommendations from the ESPEN expert groups

BACKGROUND & AIMS

Intestinal failure (IF) is defined as "the reduction of gut function below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, such that intravenous supplementation is required to maintain health and/or growth". Functionally, it may be classified as type I acute intestinal failure (AIF), type II prolonged AIF and type III chronic intestinal failure (CIF) The ESPEN Workshop on IF was held in Bologna, Italy, on 15-16 October 2017 and the aims of this document were to highlight the current state of the art and future directions for research in IF.

METHODS

This paper represents the opinion of experts in the field, based on current evidence. It is not a formal review, but encompasses the current evidence, with emphasis on epidemiology, classification, diagnosis and management.

RESULTS

IF is the rarest form of organ failure and can result from a variety of conditions that affect gastrointestinal anatomy and function adversely. Assessment, diagnosis, and short and long-term management involves a multidisciplinary team with diverse expertise in the field that aims to reduce complications, increase life expectancy and improve quality of life in patients.

CONCLUSIONS

Both AIF and CIF are relatively rare conditions and most of the published work presents evidence from small, single-centre studies. Much remains to be investigated to improve the diagnosis and management of IF and future studies should rely on multidisciplinary, multicentre and multinational collaborations that gather data from large cohorts of patients. Emphasis should also be placed on partnership with patients, carers and government agencies in order to improve the quality of research that focuses on patient-centred outcomes that will help to improve both outcomes and quality of life in patients with this devastating condition.

Simplified plasma essential amino acid-based profiling provides metabolic information and prognostic value additive to traditional risk factors in heart failure

In heart failure (HF), metabolic disturbances represent functional perturbations in peripheral tissues and also predict patient outcomes. This study developed a simplified essential amino acid-based profile and tested whether it could improve prognostication. Plasma essential amino acids and lipidomics were measured on 1084 participants. The initial cohort included 94 normal controls and 599 patients hospitalized due to acute/decompensated HF. The validation cohort included 391 HF patients. Patients were followed for composite events (death/HF related re-hospitalization) and were categorized into three groups: high risk type 1 (leucine ≥145 μM and phenylalanine ≥ 88.9 μM), high risk type 2 (leucine < 81.2 μM), and low risk (other). Types 1 and 2 were associated with higher event rates [hazard ratio (95% confidence intervals) = 1.88 (1.27-2.79) and 7.71 (4.97-11.9), respectively, p < 0.001]. Compared to the low-risk group, both types of high-risk patients were older and had lower blood pressure and estimated glomerular filtration rates, but higher B-type natriuretic peptides (BNP). In addition, type 1 was associated with more incompletely metabolized lipids in the blood; type 2 patients had lower body mass indexes, rates of using guideline-based medications, and levels of cholesterol, hemoglobin, and albumin. The prognostic value of types 1 and 2 remained significant after adjusting for age, BNP and other risk factors. The value of using high-risk types for prognosis was confirmed in the validation cohort. In conclusion, simplified essential amino acid-based profiling identified two high-risk populations and provided metabolic information and prognostic value additive to traditional risk factors.

Measuring gastric residual volumes in critically ill burn patients - A systematic review

PURPOSE

Measuring gastric residual volumes (GRV) is common in intensive care units (ICU) in patients receiving enteral nutrition (EN) and are a common source of feeding interruptions. Interruptions in EN yield adverse outcomes and are an area of improvement in burn care. The objectives of this study are to summarize the literature's ICU GRV practices and offer practical suggestions to GRV management in the burn patient.

METHODS

PubMed, SCOPUS, and OvidSP Medline were systematically reviewed using the keywords: burns; thermal injury; gastric residual volume; enteral feeding; tube feeding; enteral nutrition; gastric intolerance; ICU; critical illness. Reviews, case reports, and consensus and opinion papers were excluded.

RESULTS

26 articles were identified. Six burn-specific studies were identified. GRV practices vary widely and are a common cause of EN interruption. Elevated GRVs do not equate to gastrointestinal intolerance and do not always reflect aspiration risk.

CONCLUSIONS

We advocate a GRV threshold of 500mL should be used to optimize the benefits of EN in burn ICUs. A single incident of elevated GRVs should not mandate immediate EN rate reduction or cessation but should prompt a thoughtful examination of secondary causes of gastrointestinal intolerance. Randomized controlled trials are needed to define the ideal GRV threshold and re-evaluate its role in burn care.

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.

Comparison of Resting Energy Expenditure Assessment in Pediatric Oncology Patients

BACKGROUND

Evaluation of energy requirements is an important part of the nutrition assessment of pediatric oncology patients. Adequate provision of energy in this population is of extreme importance because of the prevalence of malnutrition and its effect on growth, development, quality of life, morbidity, and mortality. Numerous methods are used in clinical practice for estimating the resting energy expenditures (REE), specifically indirect calorimetry and predictive equations. A relatively new instrument used to assess REE is the hand-held indirect calorimeter. The purpose of this quality improvement project was to compare the accuracy of REE measurements taken by a hand-held indirect calorimeter and predictive equations to that of a standard indirect calorimeter metabolic cart.

METHODS

Patients receiving therapy for pediatric cancer, aged 7-18 years, and having a weight ≥15 kg and scheduled for a REE nutrition assessment were eligible. Sequentially, the patient's REE was assessed with the cart and the hand-held indirect calorimeter along with the predictive equation calculation.

RESULTS

Post hoc pairwise comparisons revealed that all 3 methods were significantly different from one another (P < .0001). When compared with the cart, the portable hand-held calorimeter was found to underestimate REE by 11.9%, whereas predictive equations overestimated REE by 12.4%.

CONCLUSION

Our quality improvement project suggests that the hand-held indirect calorimeter underestimated REE, and predictive equations overestimated REE in pediatric oncology nutrition assessment. Therefore, we recommend that these limitations in assessment be considered when assessing REE using a hand-held indirect calorimeter or predictive equations.

Systemic metabolism and energy consumption after microsurgical clipping and endovascular coiling for aneurysmal subarachnoid hemorrhage

BACKGROUND

The postoperative metabolic states of subarachnoid hemorrhage (SAH) patients were investigated using indirect calorimetry (IDC) and various nutritional evaluations to establish any difference in perioperative metabolic and nutritional states between microsurgical and endovascular treatment.

METHODS

This study included 30 acute aneurysmal SAH patients with ruptured intracranial aneurysms treated by surgical clipping (n = 16) or coil embolization (n = 14) at a single institute. The resting energy expenditure (REE) and respiratory quotient were measured using IDC on days 1, 4, 7, 10, 14, and 17-21 after the operation. Various blood tests, including C-reactive protein (CRP) and prealbumin, were evaluated on the same days.

RESULTS

The clipping group showed a significant increase in REE/basal energy expenditure (BEE) compared with the coiling group on days 1 and 4 (p = 0.04 and 0.03, respectively). No significant differences were found on days 7, 10, 14, and 17-21. The mean REE/BEE on days 1-14 and 1-21 showed no significant differences between the groups with repeated measures analysis of variance. The clipping group showed a significant decrease of prealbumin on day 4 and significant increase in CRP on days 1, 4, and 7.

CONCLUSIONS

The clipping group was in the hypermetabolic state compared with the coiling group during the very early postoperative period. However, the difference associated with the treatment modality was relatively small compared to the effects of the SAH and of the sequelae.

Prevalence and duration of reasons for enteral nutrition feeding interruption in a tertiary intensive care unit

OBJECTIVES

Intensive care unit (ICU) enteral nutrition (EN) can involve frequent feeding interruption (FI). The prevalence, causes, and duration of such interruption were investigated.

METHODS

Reasons for EN FI identified from extensive literature review were prospectively collected in adult mechanically ventilated critically ill patients. Results were reported by descriptive statistics. Baseline and nutritional characteristics between patients who died and those alive at day 60 were compared.

RESULTS

A total of 148 patients receiving ≥1 day of EN for the full 12-day observational period were included in the analysis. About 332 episodes of EN FI were recorded and contributed to 12.8% (4190 hours) of the total 1367 evaluable nutrition days. For each patient, FI occurred for a median of 3 days and the total duration of FI for the entire ICU stay was 24.5 hours. Median energy and protein deficits per patient due to FI for the entire ICU stay were -1780.23 kcal and -100.58 g, respectively. Duration of FI, days with FI, and the amount of energy and protein deficits due to FI were not different between patients who had died and those who were still alive at day 60 (all P > 0.05). About 72% of the total duration of EN FI was due to procedural-related and potentially avoidable causes (primarily human factors), while only about 20% was due to feeding intolerances.

CONCLUSIONS

EN FI occurred primarily due to human factors, which may be minimized by adherence to an evidence-based feeding protocol as determined by a nutrition support team.

Feeding the critically ill obese patient: a systematic review protocol

REVIEW QUESTION/OBJECTIVE

The objective of this review is to identify effective enteral nutritional regimens targeting protein and calorie delivery for the critically ill obese patient on morbidity and mortality.More specifically, the review question is:In the critically ill obese patient, what is the optimal enteral protein and calorie target that improves mortality and morbidity?

BACKGROUND

The World Health Organization (WHO) defines obesity as abnormal or excessive fat accumulation that may impair health, or, empirically, as a body mass index (BMI) ≥ 30 kg/m. Twenty-eight percent of the Australian population is obese with the prevalence rising to 44% in rural areas, and there is evidence that rates of obesity are increasing. The prevalence of obese patients in intensive care largely mirrors that of the general population. There is concern, however, that this may also be rising. A recently published multi-center nutritional study of critically ill patients reported a mean BMI of 29 in their sample, suggesting that just under 50% of their intensive care population is obese. It is inevitable, therefore, that the intensivist will care for the critically ill obese patient.Managing the critically ill obese patient is challenging, not least due to the co-morbid diseases frequently associated with obesity, including diabetes mellitus, cardiovascular disease, dyslipidaemia, sleep disordered breathing and respiratory insufficiency, hepatic steatohepatitis, chronic kidney disease and hypertension. There is also evidence that metabolic processes differ in the obese patient, particularly those with underlying insulin resistance, itself a marker of the metabolic syndrome, which may predispose to futile cycling, altered fuel utilization and protein catabolism. These issues are compounded by altered drug pharmacokinetics, and the additional logistical issues associated with prophylactic, therapeutic and diagnostic interventions.It is entirely plausible that the altered metabolic processes observed in the obese intensify and compound the metabolic changes that occur during critical illness. The early phases of critical illness are characterized by an increase in energy expenditure, resulting in a catabolic state driven by the stress response. Activation of the stress response involves up-regulation of the sympathetic nervous system and the release of pituitary hormones resulting in altered cortisol metabolism and elevated levels of endogenous catecholamines. These produce a range of metabolic disturbances including stress hyperglycemia, arising from both peripheral resistance to the effects of anabolic factors (predominantly insulin) and increased hepatic gluconeogenesis. Proteolysis is accelerated, releasing amino acids that are thought to be important in supporting tissue repair, immune defense and the synthesis of acute phase reactants. There is also altered mobilization of fuel stores, futile cycling, and evidence of altered lipoprotein metabolism. In the short term this is likely to be an adaptive response, but with time and ongoing inflammation this becomes maladaptive with a concomitant risk of protein-calorie malnutrition, immunosuppression and wasting of functional muscle tissue resulting from protein catabolism, and this is further compounded by disuse atrophy. Muscle atrophy and intensive care unit (ICU) acquired weakness is complex and poorly understood, but it is postulated that the provision of calories and sufficient protein to avoid a negative nitrogen balance mitigates this process. Avoiding lean muscle mass loss in the obese intuitively has substantial implications, given the larger mass that is required to be mobilized during their rehabilitation phase.There is, in addition, evolving evidence that hormones derived from both the gut and adipose tissue are also involved in the response to stress and critical illness, and that adipose tissue in particular is not a benign tissue bed, but rather should be considered an endocrine organ. Some of these hormones are thought to be pro-inflammatory and some anti-inflammatory; however both the net result and clinical significance of these are yet to be fully elucidated.The provision of adequate nutrition has become an integral component of supportive ICU care, but is complex. There is ongoing debate within critical care literature regarding the optimal route of delivery, the target dose, and the macronutrient components (proportion of protein and non-protein calories) of nutritional support. A number of studies have associated caloric deficit with morbidity and mortality, with the resultant assumption that prescribing sufficient calories to match energy expenditure will reduce morbidity and mortality, although the evidence base underpinning this assumption is limited to observational studies and small, randomized trials.There is research available that suggests hyper-caloric feeding or hyper-alimentation, particularly of carbohydrates, may result in increased morbidity including hyperglycemia, liver steatosis, respiratory insufficiency with prolonged duration of mechanical ventilation, re-feeding syndrome and immune suppression. But the results from studies of hypo-caloric and eucaloric feeding regimens in critically ill patients are conflicting, independent of the added metabolic complexities observed in the critically ill obese patient.Notwithstanding the debate regarding the dose and components of nutritional therapy, there is consensus that nutrition should be provided, preferably via the enteral route, and preferably initiated early in the ICU admission. The enteral route is preferred for a variety of reasons, not the least of which is cost. In addition there is evidence to suggest the enteral route is associated with the maintenance of gut integrity, a reduction in bacterial translocation and infection rates, a reduction in the incidence of stress ulceration, attenuation of oxidative stress, release of incretins and other entero-hormones, and modulation of systemic immune responses. Yet there is evidence that the initiation of enteral nutritional support for the obese critically ill patient is delayed, and that when delivered is at sub-optimal levels. The reasons for this remain obscure, but may be associated with the false assumption that every obese patient has nutritional reserves due to their adipose tissues, and can therefore withstand longer periods with no, or reduced nutritional support. In fact obesity does not necessarily protect from malnutrition, particularly protein and micronutrient malnutrition. It has been suggested by some authors that the malnutrition status of critically ill patients is a stronger predictor of mortality than BMI, and that once malnutrition status is controlled for, the apparent protective effects of obesity observed in several epidemiological studies dissipate. This would be consistent with the large body of evidence that associates malnutrition (BMI < 20 kg/m) with increased mortality, and has led some authors to postulate that the weight-mortality relationship is U-shaped. This has proven difficult to demonstrate, however, due to recognized confounding influences such as chronic co-morbidities, baseline nutritional status and the nature of the presenting critical illness.This has led to interest in nutritional regimens targeting alternative calorie and protein goals to protect the obese critically ill patient from complications arising from critical illness, and particularly protein catabolism. However, of the three major nutritional organizations, the American Society of Parenteral and Enteral Nutrition (ASPEN) is the only professional organization to make specific recommendations about providing enteral nutritional support to the critically ill obese patient, recommending a regimen targeting a hypo-caloric, high-protein goal. It is thought that this regimen, in which 60-70% of caloric requirements are provided promotes steady weight loss, while providing sufficient protein to achieve a neutral, or slightly positive, nitrogen balance, mitigating lean muscle mass loss, and allowing for wound healing. Targeting weight loss is proposed to improve insulin sensitivity, improve nursing care and reduce the risk of co-morbidities, although how this occurs and whether it can occur over the relatively short time frame of an intensive care admission (days to weeks) remains unclear. Despite these recommendations observational data of international nutritional practice suggest that ICU patients are fed uniformly low levels of calories and protein across BMI groups.Supporting the critically ill obese patient will become an increasingly important skill in the intensivist's armamentarium, and enteral nutritional therapy forms a cornerstone of this support. Yet, neither the optimal total caloric goal nor the macronutrient components of a feeding regimen for the critically ill obese patient is evident. Although the suggestion that altering the macronutrient goals for this vulnerable group of patients appears to have a sound physiological basis, the level of evidence supporting this remains unclear, and there are no systematic reviews on this topic. The aim of this systematic review is to evaluate existing literature to determine the best available evidence describing a nutritional strategy that targets energy and protein delivery to reduce morbidity and mortality for the obese patient who is critically ill.

Clinical nutrition and gastrointestinal dysfunction in critically ill stroke patients

Background Data on the epidemiology and risk factors of altered gastrointestinal motility (AGIM) is virtually lacking for patients suffering from non-traumatic neurologic diseases and stroke. This study investigated whether patterns of AGIM differ between patients with stroke and other severe acute brain diseases. Methods Clinical records of stroke and non-stroke patients treated at a neurological intensive care unit (ICU) were reviewed at day 1-5 and at day 10 after admission. The data was analyzed for the course of enteral/parenteral nutrition and for and for signs and symptoms of gastrointestinal dysfunction. The study included data of 76 patients, 57 with stroke (stroke group, SG) and 19 with other neurological diseases (non-stroke group, NSG). Results Basic demographic as well as clinical baseline characteristics and alimentation regime were similar in both groups. At least one sign of AGIM was seen in 33/57 (58%) SG and in 15/19 (79%) NSG patients (P = 0.099). Regurgitation was significantly more frequent among patients from the NSG (P < 0.05). Subjects from the NSG also spent a higher proportion of time with at least one symptom of AGIM present (P < 0.05). Conclusions For the first time, this study investigated the prevalence of AGIM in patients suffering from severe stroke. The prevalence of disturbed gastrointestinal function was found to be high in stroke patients, but was lower than in a group of non-stroke patients with similar general disease severity and baseline characteristics.

Safety of minimizing preoperative starvation in critically ill and intubated trauma patients

BACKGROUND

Cessation of enteral nutrition prior to an operation/procedure is the most common reason for feeding interruption in critically ill trauma patients and contributes to substantial calorie deficits. This study reports on a strategy to increase calorie intake by continuing feeds until transfer for operations/procedures.

METHODS

Nutrition guidelines were modified in 2006 to allow continuation of feeding in intubated patients up until transfer to the operating room. Prior to 2006, enteral feeding was stopped at least 6 hours prior to surgery. A retrospective cohort design from 2003 to 2010 compared clinical outcomes in groups of adult trauma subjects before and after guideline changes and in subjects at other centers without guideline changes.

RESULTS

During the first week, subjects in the preimplementation cohort (n = 245) received a median of 3,787 kcal per person per week, while subjects in the postimplementation cohort (n = 368) received a median of 6,662 kcal per person per week (p < 0.001). There was no change in calorie intake for subjects at other centers (n = 1,002). The risks of acute respiratory distress syndrome, pneumonia, and mortality were decreased after implementation relative to the preimplementation cohort (acute respiratory distress syndrome: relative risk ratio [RR], 0.69; 95% confidence interval [CI], 0.59-0.81; pneumonia: RR, 0.82; 95% CI, 0.65-1.00; mortality: RR, 0.67; 95% CI, 0.46-0.99). Ventilator-free days increased by 1.4 days (95% CI, 0.1-2.7), while intensive care unit stay and hospital length of stay were unchanged. These outcomes showed similar trends over time at other participating centers.

CONCLUSIONS

Allowing intubated trauma patients to continue enteral nutrition until transfer for operations or procedures was associated with increased caloric intake without evidence of increased pulmonary complications. This represents an important strategy to reduce calorie deficits in the trauma intensive care unit.

LEVEL OF EVIDENCE

Therapeutic study/care management, level III.

Metabolic Requirement of Septic Shock Patients Before and After Liberation From Mechanical Ventilation

OBJECTIVES

This study identified the difference in energy expenditure and substrate utilization of patients during and upon liberation from mechanical ventilation.

METHODS

Patients under intensive care who were diagnosed with septic shock and dependent on mechanical ventilation were recruited. Indirect calorimetry measurements were performed during and upon liberation from mechanical ventilation.

RESULTS

Thirty-five patients were recruited (20 men and 15 women; mean age, 69 ± 10 years). Measured energy expenditures during ventilation and upon liberation were 2090 ± 489 kcal·d^-1 and 1910 ± 579 kcal·d^-1, respectively ( P < .05). Energy intake was provided at 1148 ± 495 kcal·d^-1 and differed significantly from all measured energy expenditures ( P < .05). Mean carbohydrate utilization was 0.19 ± 0.1 g·min^-1 when patients were on mechanical ventilation compared with 0.15 ± 0.09 g·min^-1 upon liberation ( P < .05). Mean lipid oxidation was 0.08 ± 0.05 g·min^-1 during and 0.09 ± 0.07 g·min^-1 upon liberation from mechanical ventilation ( P > .05).

CONCLUSIONS

Measured energy expenditure was higher during than upon liberation from mechanical ventilation. This could be the increase in work of breathing from the continuous positive pressure support, repeated weaning cycles from mechanical ventilation, and/or the asynchronization between patients' respiration and ventilator support. Future studies should examine whether more appropriately matching energy expenditure with energy intake would promote positive health outcomes.

Energy-Dense Formulae May Slow Gastric Emptying in the Critically Ill

BACKGROUND

Enteral feed intolerance occurs frequently in critically ill patients and can be associated with adverse outcomes. "Energy-dense formulae" (ie, >1 kcal/mL) are often prescribed to critically ill patients to reduce administered volume and are presumed to maintain or increase calorie delivery. The aim of this study was to compare gastric emptying of standard and energy-dense formulae in critically ill patients.

METHODS

In a retrospective comparison of 2 studies, data were analyzed from 2 groups of patients that received a radiolabeled 100-mL "meal" containing either standard calories (1 kcal/mL) or concentrated calories (energy-dense formulae; 2 kcal/mL). Gastric emptying was measured using a scintigraphic technique. Radioisotope data were collected for 4 hours and gastric emptying quantified. Data are presented as mean ± SE or median [interquartile range] as appropriate.

RESULTS

Forty patients were studied (n = 18, energy-dense formulae; n = 22, standard). Groups were well matched in terms of demographics. However, patients in the energy-dense formula group were studied earlier in their intensive care unit admission (P = .02) and had a greater proportion requiring inotropes (P = .002). A similar amount of calories emptied out of the stomach per unit time (P = .57), but in patients receiving energy-dense formulae, a greater volume of meal was retained in the stomach (P = .045), consistent with slower gastric emptying.

CONCLUSIONS

In critically ill patients, the administration of the same volume of a concentrated enteral nutrition formula may not result in the delivery of more calories to the small intestine over time because gastric emptying is slowed.

Nutrition support practices in critically ill head-injured patients: a global perspective

Background

Critical illness following head injury is associated with a hypermetabolic state but there are insufficient epidemiological data describing acute nutrition delivery to this group of patients. Furthermore, there is little information describing relationships between nutrition and clinical outcomes in this population.

Methods

We undertook an analysis of observational data, collected prospectively as part of International Nutrition Surveys 2007-2013, and extracted data obtained from critically ill patients with head trauma. Our objective was to describe global nutrition support practices in the first 12 days of hospital admission after head trauma, and to explore relationships between energy and protein intake and clinical outcomes. Data are presented as mean (SD), median (IQR), or percentages.

Results

Data for 1045 patients from 341 ICUs were analyzed. The age of patients was 44.5 (19.7) years, 78 % were male, and median ICU length of stay was 13.1 (IQR 7.9-21.6) days. Most patients (94 %) were enterally fed but received only 58 % of estimated energy and 53 % of estimated protein requirements. Patients from an ICU with a feeding protocol had greater energy and protein intakes (p <0.001, 0.002 respectively) and were more likely to survive (OR 0.65; 95 % CI 0.42-0.99; p = 0.043) than those without. Energy or protein intakes were not associated with mortality. However, a greater energy and protein deficit was associated with longer times until discharge alive from both ICU and hospital (all p <0.001).

Conclusion

Nutritional deficits are commonplace in critically ill head-injured patients and these deficits are associated with a delay to discharge alive.

Nutritional management in critically ill trauma patients is challenging

Background

The physiological stress following major trauma in critical illness leads to rapid malnutrition and provision of optimal nutritional support in these circumstances can be challenging.

Case report

We present a complex trauma case where relatively aggressive nutritional support failed to minimise weight loss.

Conclusion

Nutritional support plays an integral role in the care of critically ill major trauma patients and needs to be continuously monitored in the subacute and rehabilitation phase.

Malnutrition in the ICU patient population

Malnutrition has been identified as a cause for disease as well as a condition resulting from inflammation associated with acute or chronic disease. Malnutrition is common in acute-care settings, occurring in 30% to 50% of hospitalized patients. Inflammation has been associated with malnutrition and malnutrition has been associated with compromised immune status, infection, and increased intensive care unit (ICU) and hospital length of stay. The ICU nurse is in the best position to advocate for appropriate nutritional therapies and facilitate the safe delivery of nutrition.

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

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

Evaluation of delivery of enteral nutrition in mechanically ventilated Malaysian ICU patients

BACKGROUND

There are numerous challenges in providing nutrition to the mechanically ventilated critically ill ICU patient. Understanding the level of nutritional support and the barriers to enteral feeding interruption in mechanically ventilated patients are important to maximise the nutritional benefits to the critically ill patients. Thus, this study aims to evaluate enteral nutrition delivery and identify the reasons for interruptions in mechanically ventilated Malaysian patients receiving enteral feeding.

METHODS

A cross sectional prospective study of 77 consecutive patients who required mechanical ventilation and were receiving enteral nutrition was done in an open 14-bed intensive care unit of a tertiary hospital. Data were collected prospectively over a 3 month period. Descriptive statistical analysis were made with respect to demographical data, time taken to initiate feeds, type of feeds, quantification of feeds attainment, and reasons for feed interruptions. There are no set feeding protocols in the ICU. The usual initial rate of enteral nutrition observed in ICU was 20 ml/hour, assessed every 6 hours and the decision was made thereafter to increase feeds. The target calorie for each patient was determined by the clinician alongside the dietitian. The use of prokinetic agents was also prescribed at the discretion of the attending clinician and is commonly IV metoclopramide 10 mg three times a day.

RESULTS

About 66% of patients achieved 80% of caloric requirements within 3 days of which 46.8% achieved full feeds in less than 12 hours. The time to initiate feeds for patients admitted into the ICU ranged from 0 - 110 hours with a median time to start feeds of 15 hours and the interquartile range (IQR) of 6-59 hours. The mean time to achieve at least 80% of nutritional target was 1.8 days ± 1.5 days. About 79% of patients experienced multiple feeding interruptions. The most prevalent reason for interruption was for procedures (45.1%) followed by high gastric residual volume (38.0%), diarrhoea (8.4%), difficulty in nasogastric tube placement (5.6%) and vomiting (2.9%).

CONCLUSION

Nutritional inadequacy in mechanically ventilated Malaysian patients receiving enteral nutrition was not as common as expected. However, there is still room for improvement with regards to decreasing the number of patients who did not achieve their caloric requirement throughout their stay in the ICU.

Nutritional care after critical illness: a qualitative study of patients' experiences

BACKGROUND

The present qualitative study aimed to explore the factors influencing nutritional recovery in patients after critical illness and to develop a model of care to improve current management of nutrition for this patient group.

METHODS

Patients were recruited into the study on discharge from a general intensive care unit (ICU) of a large teaching hospital in central Scotland. Semi-structured interviews were carried out after discharge from the ICU, weekly for the duration of their ward stay, and at 3 months post ICU discharge. Observations of ward practice were undertaken thrice weekly for the duration of the ward stay.

RESULTS

Seventeen patients were recruited into the study and, using a grounded theory approach, 'inter-related system breakdowns during the nutritional recovery process' emerged as the overarching core category that influenced patients' experiences of eating after critical illness. This encompassed the categories, 'experiencing a dysfunctional body', 'experiencing socio-cultural changes in relation to eating' and 'encountering nutritional care delivery failures'.

CONCLUSIONS

The findings from the present study provide a unique contribution to knowledge by offering important insights into patients' experiences of eating after critical illness. The study has identified numerous nutritional problems and raises questions about the efficacy of current nutritional management in this patient group. Adopting a more individualised approach to nutritional care could ameliorate the nutritional issues experienced by post ICU patients. This will be evaluated in future work.

Calorie intake of enteral nutrition and clinical outcomes in acutely critically ill patients: a meta-analysis of randomized controlled trials

BACKGROUND

The appropriate calorie intake to be provided to critically ill patients via enteral nutrition (EN) remains unclear. We performed a meta-analysis of randomized controlled trials to compare the effect of initial underfeeding and full feeding in acutely critically ill patients.

MATERIALS AND METHODS

We searched the Medline, EMBASE, and Cochrane Central Register of Controlled Trials databases to identify randomized controlled trials that compared underfeeding with full feeding in critically ill patients. The primary outcome was overall mortality. The secondary outcomes included length of hospital stay, length of intensive care unit (ICU) stay, duration of mechanical ventilation, incidence of pneumonia, Clostridium difficile colitis, other infectious complications, and gastrointestinal intolerance.

RESULTS

In total, 4 studies were included in this meta-analysis. There was no significant difference in overall mortality between the underfeeding and full-feeding groups (odds ratio [OR], 0.94; 95% confidence interval [CI], 0.74-1.19; I (2) = 26.6%; P = .61). Subgroup analysis of the underfeeding subgroup that was fed ≥33.3% of the standard caloric requirement indicated that overall mortality was significantly lower in this underfeeding subgroup than in the full-feeding group (OR, 0.63; 95% CI, 0.40-1.00; I (2) = 0%; P = .05). In contrast, no difference in overall mortality was noted between the underfeeding subgroup that was fed <33.3% of the standard caloric requirement and the full-feeding group. The length of hospital stay and length of ICU stay did not differ between the 2 groups. Moreover, no differences in other secondary clinical outcomes were noted.

CONCLUSIONS

None of the analyzed clinical outcomes for the acutely critically ill patients were significantly influenced by the calorie intake of the initial EN.

Adequacy of nutritional support and reasons for underfeeding in neurosurgical intensive care unit patients

PURPOSE

The purpose of the study was to identify the adequacy of enteral feeding, and the reason and prevalence of under-nutrition, and to determine the relationships between caloric intake and resulting nutritional parameters among neurosurgical intensive care unit (ICU) patients.

METHODS

The participants for this descriptive study were 47 neurosurgical ICU patients who had enteral feeding initiated after ICU admission. Data were collected from the initial day of enteral feeding for 7 days. Data related to enteral feeding, feeding interruptions or delay, prealbumin, and transferrin were collected.

RESULTS

The mean age of the participants was 56.62 years. Twenty-six patients did not receive their feeding formula more than once during 7 days, and 11 had interruptions more than 6 times. The mean number of feeding interruptions was 3.23 (SD = 4.47). On the average, only 76.44% of the estimated energy requirement was provided by enteral feeding to the patients. The frequency of underfeeding was 52.17% with respect to enteral feeding. The most frequent reason for the feeding interruption was observation before and after intubation and extubation, which was unavoidable. The next most common reason was gastrointestinal bleeding, mostly due to old clots or trace, followed by residual volume less than 100 mL. Changes in prealbumin and transferrin levels for 7 days between the underfed and adequately fed groups were not statistically significant.

CONCLUSION

The management of enteral feeding by nurses was overprotective because of the unpredictable nature of ICU patients in terms of their underlying disease process. The management of feeding intolerance needs to be evidence-based and nurses must consistently follow the protocol that has been supported as a useful measure.