Early versus late parenteral nutrition in ICU patients: cost analysis of the EPaNIC trial

Association of phenylalanine and tyrosine metabolism with mortality and response to nutritional support among patients at nutritional risk: a secondary analysis of the randomized clinical trial EFFORT

Background

Elevated phenylalanine serum level is a surrogate marker of whole-body proteolysis and has been associated with increased mortality in critically ill patients. Tyrosine is a metabolite of phenylalanine and serves as a precursor of thyroid hormones and catecholamines with important functions in the oxidative stress response among others. Herein, we examined the prognostic significance of phenylalanine, tyrosine, as well as its metabolites nitrotyrosine, L-3,4-dihydroxyphenylalanine (DOPA), and dopamine regarding clinical outcomes and response to nutritional therapy in patients at nutritional risk.

Methods

This is a secondary analysis of the Effect of Early Nutritional Support on Frailty, Functional Outcomes, and Recovery of Malnourished Medical Inpatients Trial (EFFORT), a randomized controlled trial investigating individualized nutritional support compared to standard care in patients at risk of malnutrition. The primary outcome was 30-day all-cause mortality.

Results

We analyzed data of 238 patients and found a significant association between low plasma levels of phenylalanine [adjusted HR 2.27 (95% CI 1.29 to 3.00)] and tyrosine [adjusted HR 1.91 (95% CI 1.11 to 3.28)] with increased 30-day mortality. This association persisted over a longer period, extending to 5 years. Additionally, trends indicated elevated mortality rates among patients with low nitrotyrosine and high DOPA and dopamine levels. Patients with high tyrosine levels showed a more pronounced response to nutritional support compared to patients with low tyrosine levels (HR 0.45 versus 1.46, p for interaction = 0.02).

Conclusion

In medical inpatients at nutritional risk, low phenylalanine and tyrosine levels were associated with increased short-and long-term mortality and patients with high tyrosine levels showed a more pronounced response to nutritional support. Further research is warranted to gain a deeper understanding of phenylalanine and tyrosine pathways, their association with clinical outcomes in patients at nutritional risk, as well as their response to nutritional therapy.

Clinical trial registration

www.clinicaltrials.gov, identifier NCT02517476.

Impact of withholding early parenteral nutrition on 2-year mortality and functional outcome in critically ill adults

PURPOSE

In critically ill adults, withholding parenteral nutrition until 1 week after intensive care admission (Late-PN) facilitated recovery as compared with early supplementation of insufficient enteral nutrition with parenteral nutrition (Early-PN). However, the impact on long-term mortality and functional outcome, in relation to the estimated nutritional risk, remains unclear.

METHODS

In this prospective follow-up study of the multicenter EPaNIC randomized controlled trial, we investigated the impact of Late-PN on 2-year mortality (N = 4640) and physical functioning, assessed by the 36-Item Short Form Health Survey (SF-36; in 3292 survivors, responding 819 [738-1058] days post-randomization). To account for missing data, we repeated the analyses in two imputed models. To identify potential heterogeneity of treatment effects, we investigated the impact of Late-PN in different nutritional risk subgroups as defined by Nutritional Risk Screening-2002-score, modified NUTrition Risk in the Critically Ill-score, and age (above/below 70 years), and we evaluated whether there was statistically significant interaction between classification to a nutritional risk subgroup and the effect of the randomized intervention. Secondary outcomes were SF-36-derived physical and mental component scores (PCS & MCS).

RESULTS

Two-year mortality (20.5% in Late-PN, 19.8% in Early-PN; P = 0.54) and physical functioning (70 [40-90] in both study-arms; P = 0.99) were similar in both groups, also after imputation of missing physical functioning data. Likewise, Late-PN had no impact on 2-year mortality and physical functioning in any nutritional risk subgroup. PCS and MCS were similar in both groups.

CONCLUSION

Late-PN did not alter 2-year survival and physical functioning in adult critically ill patients, independent of anticipated nutritional risk.

The Association of the Essential Amino Acids Lysine, Methionine, and Threonine with Clinical Outcomes in Patients at Nutritional Risk: Secondary Analysis of a Randomized Clinical Trial

Lysine, methionine, and threonine are essential amino acids with vital functions for muscle and connective tissue health, metabolic balance, and the immune system. During illness, the demand for these amino acids typically increases, which puts patients at risk for deficiencies with harmful clinical consequences. In a secondary analysis of the Effect of Early Nutritional Support on Frailty, Functional Outcomes, and Recovery of Malnourished Medical Inpatients Trial (EFFORT), which compared individualized nutritional support to usual care nutrition in patients at nutritional risk, we investigated the prognostic impact of the lysine, methionine, and threonine metabolism. We had complete clinical and amino acid data in 237 patients, 58 of whom reached the primary endpoint of death at 30 days. In a model adjusted for comorbidities, sex, nutritional risk, and trial intervention, low plasma methionine levels were associated with 30-day mortality (adjusted HR 1.98 [95% CI 1.16 to 3.36], p = 0.01) and with a decline in functional status (adjusted OR 2.06 [95% CI 1.06 to 4.01], p = 0.03). The results for lysine and threonine did not show statistically significant differences regarding clinical outcomes. These findings suggest that low levels of methionine may be critical during hospitalization among patients at nutritional risk. Further studies should investigate the effect of supplementation of methionine in this patient group to improve outcomes.

Our Scientific Journey through the Ups and Downs of Blood Glucose Control in the ICU

This article tells the story of our long search for the answer to one question: Is stress hyperglycemia in critically ill patients adaptive or maladaptive? Our earlier work had suggested the lack of hepatic insulin effect and hyperglycemia as jointly predicting poor outcome. Therefore, we hypothesized that insulin infusion to reach normoglycemia, tight glucose control, improves outcome. In three randomized controlled trials (RCTs), we found morbidity and mortality benefit with tight glucose control. Moving from the bed to the bench, we attributed benefits to the prevention of glucose toxicity in cells taking up glucose in an insulin-independent, glucose concentration gradient-dependent manner, counteracted rather than synergized by insulin. Several subsequent RCTs did not confirm benefit, and the large Normoglycemia in Intensive Care Evaluation-Survival Using Glucose Algorithm Regulation, or "NICE-SUGAR," trial found increased mortality with tight glucose control associated with severe hypoglycemia. Our subsequent clinical and mechanistic research revealed that early use of parenteral nutrition, the context of our initial RCTs, had been a confounder. Early parenteral nutrition (early-PN) aggravated hyperglycemia, suppressed vital cell damage removal, and hampered recovery. Therefore, in our next and largest "TGC-fast" RCT, we retested our hypothesis, without the use of early-PN and with a computer algorithm for tight glucose control that avoided severe hypoglycemia. In this trial, tight glucose control prevented kidney and liver damage, though with much smaller effect sizes than in our initial RCTs without affecting mortality. Our quest ends with the strong recommendation to omit early-PN for patients in the ICU, as this reduces need of blood glucose control and allows cellular housekeeping systems to play evolutionary selected roles in the recovery process. Once again, less is more in critical care.

Association of tryptophan pathway metabolites with mortality and effectiveness of nutritional support among patients at nutritional risk: secondary analysis of a randomized clinical trial

Tryptophan is an essential amino acid and is the precursor of many important metabolites and neurotransmitters. In malnutrition, the availability of tryptophan is reduced, potentially putting patients at increased risks. Herein, we investigated the prognostic implications of the tryptophan metabolism in a secondary analysis of the Effect of Early Nutritional Support on Frailty, Functional Outcomes, and Recovery of Malnourished Medical Inpatients Trial (EFFORT), a randomized, controlled trial comparing individualized nutritional support to usual care in patients at risk for malnutrition. Among 238 patients with available measurements, low plasma levels of metabolites were independently associated with 30-day mortality with adjusted hazard ratios (HR) of 1.77 [95% CI 1.05-2.99, p 0.034] for tryptophan, 3.49 [95% CI 1.81-6.74, p < 0.001] for kynurenine and 2.51 [95% CI 1.37-4.63, p 0.003] for serotonin. Nutritional support had more beneficial effects on mortality in patients with high tryptophan compared to patients with low tryptophan levels (adjusted HR 0.61 [95% CI 0.29-1.29] vs. HR 1.72 [95% CI 0.79-3.70], p for interaction 0.047). These results suggest that sufficient circulating levels of tryptophan might be a metabolic prerequisite for the beneficial effect of nutritional interventions in this highly vulnerable patient population.

Nutritional status of patients with COVID-19 one year post-ICU stay: a prospective observational study

Objective

Patients discharged from the Intensive Care Unit (ICU) often suffer from physical complaints and poor nutritional intake, which negatively affect nutritional status (NS). Our aim was to describe NS of patients with COVID-19 one year post-ICU stay.

Research Methods & Procedures

Observational study of adult patients with COVID-19 one year post-ICU. NS assessment (nutrient balance, body composition and physical status) was performed. Nutritional intake and nutrition-related complaints were examined. Nutritional requirements were determined with indirect calorimetry and body composition with bio-electrical impedance. Fat-free mass index (FFMI) and fat mass index (FMI) were calculated. Physical status was determined with handgrip strength (HGS), 6-minute walk test, and 1-minute sit to stand test (1MSTST). Descriptive statistics and paired sample t-tests were used for analysis.

Results

We included 48 patients (73% male; median age 60 years [IQR 52;65]). Median weight loss during ICU stay was 13%. One year post-ICU 12% weight was regained. Median BMI was 26 kg/m² and 23% was obese (BMI>30 kg/m² and high FMI). Of the patients, 50% had high FMI and 19% had low FFMI. Median reported nutritional intake was 90% of measured resting energy expenditure. Nutrition-related complaints were seen in 16%. Percentages of normal values reached in physical tests were 92% of HGS, 95% of 6 minute walking distance and 79% of 1MSTST.

Conclusion(s)

Despite almost fully regained weight and good physical recovery in adult patients one year post-ICU stay, NS remained impaired due to elevated FMI, even though reported nutritional intake was below the estimated requirements.

Early Amino Acids in Extremely Preterm Infants and Neurodisability at 2 Years

BACKGROUND

Whether higher parenteral amino acid intake improves outcomes in infants with extremely low birth weight is unclear.

METHODS

In this multicenter, parallel-group, double-blind, randomized, placebo-controlled trial, we assigned infants with birth weights of less than 1000 g at 8 neonatal intensive care units to receive amino acids at a dose of 1 g per day (intervention group) or placebo in addition to usual nutrition for the first 5 days after birth. The primary outcome was survival free from neurodisability as assessed with the Bayley Scales of Infant and Toddler Development and neurologic examination at 2 years, corrected for gestational age at birth. Secondary outcomes were the components of the primary outcome as well as the presence or absence of neonatal disorders, the rate of growth, and nutritional intake.

RESULTS

We enrolled 434 infants (217 per group) in this trial. Survival free from neurodisability was observed in 97 of 203 children (47.8%) in the intervention group and in 102 of 205 (49.8%) in the placebo group (adjusted relative risk, 0.95; 95% confidence interval [CI], 0.79 to 1.14; P = 0.56). Death before the age of 2 years occurred in 39 of 217 children (18.0%) in the intervention group and 42 of 217 (19.4%) in the placebo group (adjusted relative risk, 0.93; 95% CI, 0.63 to 1.36); neurodisability occurred in 67 of 164 children (40.9%) in the intervention group and 61 of 163 (37.4%) in the placebo group (adjusted relative risk, 1.16; 95% CI, 0.90 to 1.50). Neurodisability was moderate to severe in 27 children (16.5%) in the intervention group and 14 (8.6%) in the placebo group (adjusted relative risk, 1.95; 95% CI, 1.09 to 3.48). More children in the intervention group than in the placebo group had patent ductus arteriosus (adjusted relative risk, 1.65; 95% CI, 1.11 to 2.46). In a post hoc analysis, refeeding syndrome occurred in 42 of 172 children in the intervention group and 26 of 166 in the placebo group (adjusted relative risk, 1.64; 95% CI, 1.09 to 2.47). Eight serious adverse events occurred.

CONCLUSIONS

In infants with extremely low birth weight, extra parenteral amino acids at a dose of 1 g per day for 5 days after birth did not increase the number who survived free from neurodisability at 2 years. (Funded by the New Zealand Health Research Council and others; ProVIDe Australian New Zealand Clinical Trials Registry number, ACTRN12612001084875.).

Impact of tight blood glucose control within normal fasting ranges with insulin titration prescribed by the Leuven algorithm in adult critically ill patients: the TGC-fast randomized controlled trial

Background

It remains controversial whether critical illness-related hyperglycemia should be treated or not, since randomized controlled trials (RCTs) have shown context-dependent outcome effects. Whereas pioneer RCTs found improved outcome by normalizing blood glucose in patients receiving early parenteral nutrition (PN), a multicenter RCT revealed increased mortality in patients not receiving early PN. Although withholding early PN has become the feeding standard, the multicenter RCT showing harm by tight glucose control in this context has been criticized for its potentially unreliable glucose control protocol. We hypothesize that tight glucose control is effective and safe using a validated protocol in adult critically ill patients not receiving early PN.

Methods

The TGC-fast study is an investigator-initiated, multicenter RCT. Patients unable to eat, with need for arterial and central venous line and without therapy restriction, are randomized upon ICU admission to tight (80–110 mg/dl) or liberal glucose control (only initiating insulin when hyperglycemia >215 mg/dl, and then targeting 180–215 mg/dl). Glucose measurements are performed on arterial blood by a blood gas analyzer, and if needed, insulin is only administered continuously through a central venous line. If the arterial line is no longer needed, glucose is measured on capillary blood. In the intervention group, tight control is guided by the validated LOGIC-Insulin software. In the control arm, a software alert is used to maximize protocol compliance. The intervention is continued until ICU discharge, until the patient is able to eat or no longer in need of a central venous line, whatever comes first. The study is powered to detect, with at least 80% power and a 5% alpha error rate, a 1-day difference in ICU dependency (primary endpoint), and a 1.5% increase in hospital mortality (safety endpoint), for which 9230 patients need to be included. Secondary endpoints include acute and long-term morbidity and mortality, and healthcare costs. Biological samples are collected to study potential mechanisms of organ protection.

Discussion

The ideal glucose target for critically ill patients remains debated. The trial will inform physicians on the optimal glucose control strategy in adult critically ill patients not receiving early PN.

Trial registration

ClinicalTrials.gov NCT03665207. Registered on 11 September 2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06709-8.

Hospital-acquired infections after acute ischaemic stroke and its association with healthcare-related costs and functional outcome

INTRODUCTION

Acute ischaemic stroke is associated with important mortality, morbidity, and healthcare-related costs. Age, pre-stroke functionality and stroke severity are important contributors to functional outcome. Stroke patients also risk developing infections during hospitalization. We sought to explore possible predictors of post-stroke infections and the relationship of post-stroke infection with healthcare-related costs and functional outcome.

METHODS

This single-centre retrospective study included 530 patients treated for ischaemic stroke between January 2017 and February 2019. Antibiotics' administration was used as a proxy for post-stroke infection. Functional outcome at 90 days was assessed by the modified Rankin Scale (mRS). Total healthcare-related costs were recorded for the index hospital stay. Multivariable analysis for post-stroke infection was done with the independent factors sex, age, pre-stroke mRS, National Institutes of Health Stroke Scale (NIHSS) and diabetes mellitus.

RESULTS

Twenty percent of patients had a post-stroke infection. NIHSS (OR 1.10, 95%CI 1.06-1.13, p < 0.0001) and diabetes mellitus (OR 2.18, 95%CI 1.28-3.71, p = 0.0042) were independent predictors for post-stroke infection. Mean total healthcare-related costs were 15,374 euro (SD 19,968; IQR 3,380-18,165), with a mean of 31,061 euro (SD 29,995; IQR 12,584-42,843) in patients with infection, compared to 11,406 euro (SD 13,987; IQR 3,083-12,726) in patients without (p < 0.0001). Median 90-days mRS was 5 (IQR 3-6) in patients with infection versus 1 (IQR 0-3.5) in patients without (p < 0.0001).

CONCLUSIONS

In patients, admitted for acute ischaemic stroke, stroke severity and diabetes mellitus were identified as the main predictors for post-stroke infection. Hospital-acquired infections were associated with increased costs and worse functional outcome.

Early versus later initiation of parenteral nutrition for very preterm infants: a propensity score-matched observational study

OBJECTIVE

To evaluate the impact of timing of initiation of parenteral nutrition (PN) after birth in very preterm infants.

DESIGN

Propensity-matched analysis of data from the UK National Neonatal Research Database.

PATIENTS

65 033 babies <31 weeks gestation admitted to neonatal units in England and Wales between 2008 and 2019.

INTERVENTIONS

PN initiated in the first 2 days (early) versus after the second postnatal day (late). Babies who died in the first 2 days without receiving PN were analysed as 'late'.

MAIN OUTCOME MEASURES

The main outcome measure was morbidity-free survival to discharge. The secondary outcomes were survival to discharge, growth and other core neonatal outcomes.

FINDINGS

No difference was found in the primary outcome (absolute rate difference (ARD) between early and late 0.50%, 95% CI -0.45 to 1.45, p=0.29). The early group had higher rates of survival to discharge (ARD 3.3%, 95% CI 2.7 to 3.8, p<0.001), late-onset sepsis (ARD 0.84%, 95% CI 0.48 to 1.2, p<0.001), bronchopulmonary dysplasia (ARD 1.24%, 95% CI 0.30 to 2.17, p=0.01), treated retinopathy of prematurity (ARD 0.50%, 95% CI 0.17 to 0.84, p<0.001), surgical procedures (ARD 0.80%, 95% CI 0.20 to 1.40, p=0.01) and greater drop in weight z-score between birth and discharge (absolute difference 0.019, 95% CI 0.003 to 0.035, p=0.02). Of 4.9% of babies who died in the first 2 days, 3.4% were in the late group and not exposed to PN.

CONCLUSIONS

Residual confounding and survival bias cannot be excluded and justify the need for a randomised controlled trial powered to detect differences in important functional outcomes.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Meeting nutritional targets of critically ill patients by combined enteral and parenteral nutrition: review and rationale for the EFFORTcombo trial

While medical nutrition therapy is an essential part of the care for critically ill patients, uncertainty exists about the right form, dosage, timing and route in relation to the phases of critical illness. As enteral nutrition (EN) is often withheld or interrupted during the intensive care unit (ICU) stay, combined EN and parenteral nutrition (PN) may represent an effective and safe option to achieve energy and protein goals as recommended by international guidelines. We hypothesise that critically ill patients at high nutritional risk may benefit from such a combined approach during their stay on the ICU. Therefore, we aim to test if an early combination of EN and high-protein PN (EN+PN) is effective in reaching energy and protein goals in patients at high nutritional risk, while avoiding overfeeding. This approach will be tested in the here-presented EFFORTcombo trial. Nutritionally high-risk ICU patients will be randomised to either high (≥2·2 g/kg per d) or low protein (≤1·2 g/kg per d). In the high protein group, the patients will receive EN+PN; in the low protein group, patients will be given EN alone. EN will be started in accordance with international guidelines in both groups. Efforts will be made to reach nutrition goals within 48-96 h. The efficacy of the proposed nutritional strategy will be tested as an innovative approach by functional outcomes at ICU and hospital discharge, as well as at a 6-month follow-up.

Association of Baseline Inflammation With Effectiveness of Nutritional Support Among Patients With Disease-Related Malnutrition: A Secondary Analysis of a Randomized Clinical Trial

IMPORTANCE

Inflammation is a key driver of malnutrition during illness and is often accompanied by metabolic effects, including insulin resistance and reduction of appetite. However, it still remains unclear if inflammation influences the response to nutritional support among patients with disease-related malnutrition.

OBJECTIVE

To examine whether patients' baseline inflammatory status is associated with the effect of nutritional support on 30-day mortality.

DESIGN, SETTING, AND PARTICIPANTS

This is a secondary analysis of the Effect of Early Nutritional Support on Frailty, Functional Outcomes, and Recovery of Malnourished Medical Inpatients Trial (EFFORT), a randomized clinical trial conducted in 8 Swiss hospitals from April 2014 to February 2018. A total of 1950 participants who had C-reactive protein measurements at the time of admission were included in this secondary analysis. Data analysis was conducted between June and July 2019.

INTERVENTIONS

Hospitalized patients at risk for malnutrition were randomly assigned to receive protocol-guided individualized nutritional support to reach protein and energy goals (intervention group) or standard hospital food (control group).

MAIN OUTCOMES AND MEASURES

The primary end point was 30-day mortality. Based on C-reactive protein levels at admission, patients were stratified into groups with low, moderate, or high inflammation (<10 mg/L, 10-100 mg/L, and >100 mg/L, respectively).

RESULTS

A total of 1950 patients (median [interquartile range] age, 75 [65-83] years; 1025 [52.6%] men) were included; 533 (27.3%) had low levels of inflammation, 894 (45.9%) had moderate levels of inflammation, and 523 (26.8%) had high levels of inflammation. Compared with the control group, patients receiving nutritional support showed a significant reduction in 30-day mortality, regardless of C-reactive protein level (adjusted odds ratio, 0.61; 95% CI, 0.43-0.86; P = .005). In the subgroup of patients with high inflammation, there was no beneficial effect of nutritional support (adjusted odds ratio, 1.32; 95% CI, 0.70-2.50; P = .39), providing evidence that inflammation has a significant modifying association (P for interaction = .005).

CONCLUSIONS AND RELEVANCE

Based on this secondary analysis of a multicenter randomized trial, a patient's admission inflammatory status was associated with their response to nutritional support. If validated in future clinical trials, nutritional support may need to be individualized based on a patient's initial presentation and markers of inflammation. These results may also help to explain some of the heterogeneity in treatment effects of nutrition seen in previous critical care trials.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02517476.

Medical Nutrition Therapy in Critically Ill Patients Treated on Intensive and Intermediate Care Units: A Literature Review

Medical nutrition therapy in critically ill patients remains challenging, not only because of the pronounced stress response with a higher risk for complications, but also due to their heterogeneity evolving from different phases of illness. The present review aims to address current knowledge and guidelines in order to summarize how they can be best implemented into daily clinical practice. Further studies are urgently needed to answer such important questions as best timing, route, dose, and composition of medical nutrition therapy for critically ill patients and to determine how to assess and to adapt to patients’ individual needs.

The soluble mannose receptor (sMR/sCD206) in critically ill patients with invasive fungal infections, bacterial infections or non-infectious inflammation: a secondary analysis of the EPaNIC RCT

Background

Invasive fungal infections (IFI) are difficult to diagnose, especially in critically ill patients. As the mannose receptor (MR) is shed from macrophage cell surfaces after exposure to fungi, we investigate whether its soluble serum form (sMR) can serve as a biomarker of IFI.

Methods

This is a secondary analysis of the multicentre randomised controlled trial (EPaNIC, n = 4640) that investigated the impact of initiating supplemental parenteral nutrition (PN) early during critical illness (Early-PN) as compared to withholding it in the first week of intensive care (Late-PN). Serum sMR concentrations were measured in three matched patient groups (proven/probable IFI, n = 82; bacterial infection, n = 80; non-infectious inflammation, n = 77) on the day of antimicrobial initiation or matched intensive care unit day and the five preceding days, as well as in matched healthy controls (n = 59). Independent determinants of sMR concentration were identified via multivariable linear regression. Serum sMR time profiles were analysed with repeated-measures ANOVA. Predictive properties were assessed via area under the receiver operating curve (aROC).

Results

Serum sMR was higher in IFI patients than in all other groups (all p < 0.02), aROC to differentiate IFI from no IFI being 0.65 (p < 0.001). The ability of serum sMR to discriminate infectious from non-infectious inflammation was better with an aROC of 0.68 (p < 0.001). The sMR concentrations were already elevated up to 5 days before antimicrobial initiation and remained stable over time. Multivariable linear regression analysis showed that an infection or an IFI, higher severity of illness and sepsis upon admission were associated with higher sMR levels; urgent admission and Late-PN were independently associated with lower sMR concentrations.

Conclusion

Serum sMR concentrations were higher in critically ill patients with IFI than in those with a bacterial infection or with non-infectious inflammation. However, test properties were insufficient for diagnostic purposes.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2549-8) contains supplementary material, which is available to authorized users.

Impact of supplemental parenteral nutrition early during critical illness on invasive fungal infections: a secondary analysis of the EPaNIC randomized controlled trial

OBJECTIVE

In the EPaNIC RCT (N=4640), postponing the administration of parenteral nutrition (PN) to beyond 1 week in the intensive care unit (ICU) (late-PN) reduced the number of ICU-acquired infections and the costs for antimicrobial drugs compared with initiation of PN within 24-48 hours of admission (early-PN). In a secondary analysis, we hypothesize that late-PN reduces the odds to acquire an invasive fungal infection (IFI) in the ICU.

METHODS

The impact of late-PN (N=2328) versus early-PN (N=2312) on acquired IFI and on the likelihood to acquire an IFI over time was assessed in univariable and multivariable analyses. Subsequently, we performed multivariable analyses to assess the effect of the mean total daily administered calories from admission until day 3, day 5, and day 7 on the likelihood over time of acquiring an IFI.

RESULTS

Fewer late-PN patients acquired an IFI compared with early-PN patients (77/2328 versus 112/2312) (p 0.008). After adjusting for risk factors, the odds to acquire an IFI and the likelihood of acquiring an IFI at any time were lower in late-PN (adjusted odds ratio 0.66, 95% CI 0.48-0.90, p 0.009; adjusted hazard ratio (HRadj) 0.70, 95% CI 0.52-0.93, p 0.02). Larger caloric amounts from admission until day 7 were associated with a higher likelihood to acquire an IFI over time (HRadj 1.09, 95% CI 1.02-1.16, p 0.009).

CONCLUSION

Postponing PN to beyond 1 week and smaller caloric amounts until day 7 in the ICU reduced ICU-acquired IFIs and the likelihood to develop an IFI over time.

Parenteral nutrition in the critically ill

PURPOSE OF REVIEW

Feeding guidelines have recommended early, full nutritional support in critically ill patients to prevent hypercatabolism and muscle weakness. Early enteral nutrition was suggested to be superior to early parenteral nutrition. When enteral nutrition fails to meet nutritional target, it was recommended to administer supplemental parenteral nutrition, albeit with a varying starting point. Sufficient amounts of amino acids were recommended, with addition of glutamine in subgroups. Recently, several large randomized controlled trials (RCTs) have yielded important new insights. This review summarizes recent evidence with regard to the indication, timing, and dosing of parenteral nutrition in critically ill patients.

RECENT FINDINGS

One large RCT revealed no difference between early enteral nutrition and early parenteral nutrition. Two large multicenter RCTs showed harm by early supplementation of insufficient enteral nutrition with parenteral nutrition, which could be explained by feeding-induced suppression of autophagy. Several RCTs found either no benefit or harm with a higher amino acid or caloric intake, as well as harm by administration of glutamine.

SUMMARY

Although unanswered questions remain, current evidence supports accepting low macronutrient intake during the acute phase of critical illness and does not support use of early parenteral nutrition. The timing when parenteral nutrition can be initiated safely and effectively is unclear.

Early versus late parenteral nutrition in critically ill, term neonates: a preplanned secondary subgroup analysis of the PEPaNIC multicentre, randomised controlled trial

BACKGROUND

Previous randomised studies showed that withholding parenteral nutrition for 1 week of critical illness was superior to early initiation (<24-48 h) of parenteral nutrition in children and adults. However, neonates are considered more susceptible to macronutrient deficits. We investigated the effect of withholding parenteral nutrition for 1 week in critically ill, term neonates.

METHODS

We previously did a randomised, controlled study (PEPaNIC) of children aged up to 17 years admitted to paediatric intensive-care units (ICUs) in three hospitals in Belgium, Canada, and the Netherlands randomly assigned (1:1) to either standard care of parenteral nutrition initiated early within 24 h of admission to an ICU or late parenteral nutrition (where supplemental parenteral nutrition was withheld for 1 week after admission to the ICU). In this preplanned, secondary subanalysis of PEPaNIC, we looked at data from critically ill, term neonate participants (gestational age ≥37 weeks) aged up to 28 days (studied in overlapping age groups of ≤4 weeks, ≤1 week, and <1 day-ie, age at admission). In both the early parenteral nutrition and late parenteral nutrition groups, enteral nutrition was initiated as soon as possible and increased according to local protocols. Outcome assessors and investigators not directly involved in the paediatric ICU were not informed of treatment allocation. The primary endpoints were incidence of new infections and duration of paediatric ICU dependency (quantified as the number of days in the paediatric ICU and likelihood of earlier live discharge from the ICU), analysed based on intention to treat. Multivariable analyses were adjusted for the following risk factors: centre, Paediatric Logistic Organ Dysfunction score, Paediatric Index of Mortality 2 score, diagnosis group, and weight-for-age Z scores on admission. Secondary safety outcomes were mortality (at 90 days, during the intervention, in the paediatric ICU, and in the hospital) and hypoglycaemic incidents during the intervention. All patients in the respective groups were included in the safety analysis.

FINDINGS

Between June 18, 2012, and July 27, 2015, we included 209 participants in this substudy, 145 of whom were aged up to and including 1 week and 45 aged younger than 1 day. In neonates aged up to and including 4 weeks, late parenteral nutrition increased the likelihood of earlier live discharge from the paediatric ICU compared with early parenteral nutrition (adjusted hazard ratio [HR] 1·61, 95% CI 1·19-2·20; p=0·0021) but did not affect the risk of infection. The risk of infection in neonates aged up to and including 1 week and younger than 1 day was lower with late parenteral nutrition than with early parenteral nutrition (adjusted odds ratios [OR] 0·36, 95% CI 0·15-0·83, p=0·017; and 0·10, 0·01-0·64, p=0·015, respectively). For neonates aged up to and including 1 week, the likelihood of an earlier live discharge from the ICU was higher with late parenteral nutrition (adjusted HR 1·69, 95% CI 1·16-2·46; p=0·0063). For neonates younger than 1 day, adjusted HR was 1·95 (95% CI 0·93-4·12; p=0·078). Mortality at all studied timepoints was similar between the groups for all ages; however, in neonates aged up to and including 4 weeks and aged up to and including 1 week, the risk of hypoglycaemia was higher with late parenteral nutrition (23% vs 14%; adjusted OR 3·05, 95% CI 1·27-7·35, p=0·013; and 24% vs 14%; 3·57, 1·23-10·45, p=0·019, respectively.

INTERPRETATION

In critically ill, term neonates, withholding parenteral nutrition for 1 week was clinically superior to standard care of initiating parenteral nutrition within 24 h for short-term outcomes. However, withholding parenteral nutrition for 1 week significantly increased the risk of developing hypoglycaemia, which necessitates long-term follow-up of these children before late parenteral nutrition can be confidently recommended for this vulnerable patient group.

FUNDING

Flemish Agency for Innovation through Science and Technology, Methusalem-Programme Flemish Government, European Research Council, Fonds NutsOhra, Stichting Agis-Zorginnovatie, and the Sophia Research-Foundation.

Parenteral nutrition in intensive care patients: medicoeconomic aspects

PURPOSE OF REVIEW

Parenteral nutrition (PN) alone or as supplemental parenteral nutrition (SPN) has been shown to prevent negative cumulative energy balance, to improve protein delivery and, in some studies, to reduce infectious morbidity in ICU patients who fail to cover their needs with enteral nutrition (EN) alone.

RECENT FINDINGS

The optimization of energy provision to an individualized energy target using either early PN or SPN within 3-4 days after admission has recently been reported to be a cost-saving strategy mediated by a reduction of infectious complications in selected intensive care patients.

SUMMARY

EN alone is often insufficient, or occasionally contraindicated, in critically ill patients and results in growing energy and protein deficit. The cost benefit of using early PN in patients with short-term relative contraindications to EN has been reported. In selected patients SPN has been associated with a decreased risk of infection, a reduced duration of mechanical ventilation, a shorter stay in the ICU. Altogether four studies have investigated the costs associated with these interventions since 2012: two of them from Australia and Switzerland have shown that optimization of energy provision using SPN results in cost reduction, conflicting with other studies. The latter encouraging findings require further validation.

Cost-effectiveness study of early versus late parenteral nutrition in critically ill children (PEPaNIC): preplanned secondary analysis of a multicentre randomised controlled trial

Background

The multicentre randomised controlled PEPaNIC trial showed that withholding parenteral nutrition (PN) during the first week of critical illness in children was clinically superior to providing early PN. This study describes the cost-effectiveness of this new nutritional strategy.

Methods

Direct medical costs were calculated with use of a micro-costing approach. We compared the costs of late versus early initiation of PN (n = 673 versus n = 670 patients) in the Belgian and Dutch study populations from a hospital perspective, using Student’s t test with bootstrapping. Main cost drivers were identified and the impact of new infections on the total costs was assessed.

Results

Mean direct medical costs for patients receiving late PN (€26.680, IQR €10.090–28.830 per patient) were 21% lower (-€7.180, p = 0.007) than for patients receiving early PN (€33.860, IQR €11.080–34.720). Since late PN was more effective and less costly, this strategy was superior to early PN. The lower costs for PN only contributed 2.1% to the total cost reduction. The main cost driver was intensive care hospitalisation costs (-€4.120, p = 0.003). The patients who acquired a new infection (14%) were responsible for 41% of the total costs. Sensitivity analyses confirmed consistency across both healthcare systems.

Conclusions

Late initiation of PN decreased the direct medical costs for hospitalisation in critically ill children, beyond the expected lower costs for withholding PN. Avoiding new infections by late initiation of PN yielded a large cost reduction. Hence, late initiation of PN was superior to early initiation of PN largely via its effect on new infections.

Trial registration

ClinicalTrials.gov, NCT01536275. Registered on 16 February 2012.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1936-2) contains supplementary material, which is available to authorized users.

Nutrition support in hospitalised adults at nutritional risk

BACKGROUND

The prevalence of disease-related malnutrition in Western European hospitals is estimated to be about 30%. There is no consensus whether poor nutritional status causes poorer clinical outcome or if it is merely associated with it. The intention with all forms of nutrition support is to increase uptake of essential nutrients and improve clinical outcome. Previous reviews have shown conflicting results with regard to the effects of nutrition support.

OBJECTIVES

To assess the benefits and harms of nutrition support versus no intervention, treatment as usual, or placebo in hospitalised adults at nutritional risk.

SEARCH METHODS

We searched Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE (Ovid SP), Embase (Ovid SP), LILACS (BIREME), and Science Citation Index Expanded (Web of Science). We also searched the World Health Organization International Clinical Trials Registry Platform (www.who.int/ictrp); ClinicalTrials.gov; Turning Research Into Practice (TRIP); Google Scholar; and BIOSIS, as well as relevant bibliographies of review articles and personal files. All searches are current to February 2016.

SELECTION CRITERIA

We include randomised clinical trials, irrespective of publication type, publication date, and language, comparing nutrition support versus control in hospitalised adults at nutritional risk. We exclude trials assessing non-standard nutrition support.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane and the Cochrane Hepato-Biliary Group. We used trial domains to assess the risks of systematic error (bias). We conducted Trial Sequential Analyses to control for the risks of random errors. We considered a P value of 0.025 or less as statistically significant. We used GRADE methodology. Our primary outcomes were all-cause mortality, serious adverse events, and health-related quality of life.

MAIN RESULTS

We included 244 randomised clinical trials with 28,619 participants that met our inclusion criteria. We considered all trials to be at high risk of bias. Two trials accounted for one-third of all included participants. The included participants were heterogenous with regard to disease (20 different medical specialties). The experimental interventions were parenteral nutrition (86 trials); enteral nutrition (tube-feeding) (80 trials); oral nutrition support (55 trials); mixed experimental intervention (12 trials); general nutrition support (9 trials); and fortified food (2 trials). The control interventions were treatment as usual (122 trials); no intervention (107 trials); and placebo (15 trials). In 204/244 trials, the intervention lasted three days or more.We found no evidence of a difference between nutrition support and control for short-term mortality (end of intervention). The absolute risk was 8.3% across the control groups compared with 7.8% (7.1% to 8.5%) in the intervention groups, based on the risk ratio (RR) of 0.94 (95% confidence interval (CI) 0.86 to 1.03, P = 0.16, 21,758 participants, 114 trials, low quality of evidence). We found no evidence of a difference between nutrition support and control for long-term mortality (maximum follow-up). The absolute risk was 13.2% in the control group compared with 12.2% (11.6% to 13%) following nutritional interventions based on a RR of 0.93 (95% CI 0.88 to 0.99, P = 0.03, 23,170 participants, 127 trials, low quality of evidence). Trial Sequential Analysis showed we only had enough information to assess a risk ratio reduction of approximately 10% or more. A risk ratio reduction of 10% or more could be rejected.We found no evidence of a difference between nutrition support and control for short-term serious adverse events. The absolute risk was 9.9% in the control groups versus 9.2% (8.5% to 10%), with nutrition based on the RR of 0.93 (95% CI 0.86 to 1.01, P = 0.07, 22,087 participants, 123 trials, low quality of evidence). At long-term follow-up, the reduction in the risk of serious adverse events was 1.5%, from 15.2% in control groups to 13.8% (12.9% to 14.7%) following nutritional support (RR 0.91, 95% CI 0.85 to 0.97, P = 0.004, 23,413 participants, 137 trials, low quality of evidence). However, the Trial Sequential Analysis showed we only had enough information to assess a risk ratio reduction of approximately 10% or more. A risk ratio reduction of 10% or more could be rejected.Trial Sequential Analysis of enteral nutrition alone showed that enteral nutrition might reduce serious adverse events at maximum follow-up in people with different diseases. We could find no beneficial effect of oral nutrition support or parenteral nutrition support on all-cause mortality and serious adverse events in any subgroup.Only 16 trials assessed health-related quality of life. We performed a meta-analysis of two trials reporting EuroQoL utility score at long-term follow-up and found very low quality of evidence for effects of nutritional support on quality of life (mean difference (MD) -0.01, 95% CI -0.03 to 0.01; 3961 participants, two trials). Trial Sequential Analyses showed that we did not have enough information to confirm or reject clinically relevant intervention effects on quality of life.Nutrition support may increase weight at short-term follow-up (MD 1.32 kg, 95% CI 0.65 to 2.00, 5445 participants, 68 trials, very low quality of evidence).

AUTHORS' CONCLUSIONS

There is low-quality evidence for the effects of nutrition support on mortality and serious adverse events. Based on the results of our review, it does not appear to lead to a risk ratio reduction of approximately 10% or more in either all-cause mortality or serious adverse events at short-term and long-term follow-up.There is very low-quality evidence for an increase in weight with nutrition support at the end of treatment in hospitalised adults determined to be at nutritional risk. The effects of nutrition support on all remaining outcomes are unclear.Despite the clinically heterogenous population and the high risk of bias of all included trials, our analyses showed limited signs of statistical heterogeneity. Further trials may be warranted, assessing enteral nutrition (tube-feeding) for different patient groups. Future trials ought to be conducted with low risks of systematic errors and low risks of random errors, and they also ought to assess health-related quality of life.

Supplemental parenteral nutrition in intensive care patients: A cost saving strategy

BACKGROUND & AIMS

The Swiss supplemental parenteral nutrition (SPN) study demonstrated that optimised energy provision combining enteral nutrition (EN) and SPN reduces nosocomial infections in critically ill adults who fail to achieve targeted energy delivery with EN alone. To assess the economic impact of this strategy, we performed a cost-effectiveness analysis using data from the SPN study.

METHODS

Multivariable regression analyses were performed to characterise the relationships between SPN, cumulative energy deficit, nosocomial infection, and resource consumption. The results were used as inputs for a deterministic simulation model evaluating the cost-effectiveness of SPN administered on days 4-8 in patients who fail to achieve ≥60% of targeted energy delivery with EN by day 3. Cost data were derived primarily from Swiss diagnosis-related case costs and official labour statistics.

RESULTS

Provision of SPN on days 4-8 was associated with a mean decrease of 2320 ± 338 kcal in cumulative energy deficit compared with EN alone (p < 0.001). Logistic regression analysis showed that each 1000 kcal decrease in cumulative energy deficit was associated with a 10% reduction in the risk of nosocomial infection (odds ratio 0.90; 95% confidence interval 0.83-0.99; p < 0.05). The incremental cost per avoided infection was -63,048 CHF, indicating that the reduction in infection was achieved at a lower cost.

CONCLUSION

Optimisation of energy provision using SPN is a cost-saving strategy in critically ill adults for whom EN is insufficient to meet energy requirements.

A multicentre, randomised controlled trial comparing the clinical effectiveness and cost-effectiveness of early nutritional support via the parenteral versus the enteral route in critically ill patients (CALORIES)

BACKGROUND

Malnutrition is a common problem in critically ill patients in UK NHS critical care units. Early nutritional support is therefore recommended to address deficiencies in nutritional state and related disorders in metabolism. However, evidence is conflicting regarding the optimum route (parenteral or enteral) of delivery.

OBJECTIVES

To estimate the effect of early nutritional support via the parenteral route compared with the enteral route on mortality at 30 days and on incremental cost-effectiveness at 1 year. Secondary objectives were to compare the route of early nutritional support on duration of organ support; infectious and non-infectious complications; critical care unit and acute hospital length of stay; all-cause mortality at critical care unit and acute hospital discharge, at 90 days and 1 year; survival to 90 days and 1 year; nutritional and health-related quality of life, resource use and costs at 90 days and 1 year; and estimated lifetime incremental cost-effectiveness.

DESIGN

A pragmatic, open, multicentre, parallel-group randomised controlled trial with an integrated economic evaluation.

SETTING

Adult general critical care units in 33 NHS hospitals in England.

PARTICIPANTS

2400 eligible patients.

INTERVENTIONS

Five days of early nutritional support delivered via the parenteral (n = 1200) and enteral (n = 1200) route.

MAIN OUTCOME MEASURES

All-cause mortality at 30 days after randomisation and incremental net benefit (INB) (at £20,000 per quality-adjusted life-year) at 1 year.

RESULTS

By 30 days, 393 of 1188 (33.1%) patients assigned to receive early nutritional support via the parenteral route and 409 of 1195 (34.2%) assigned to the enteral route had died [p = 0.57; absolute risk reduction 1.15%, 95% confidence interval (CI) -2.65 to 4.94; relative risk 0.97 (0.86 to 1.08)]. At 1 year, INB for the parenteral route compared with the enteral route was negative at -£1320 (95% CI -£3709 to £1069). The probability that early nutritional support via the parenteral route is more cost-effective - given the data - is < 20%. The proportion of patients in the parenteral group who experienced episodes of hypoglycaemia (p = 0.006) and of vomiting (p < 0.001) was significantly lower than in the enteral group. There were no significant differences in the 15 other secondary outcomes and no significant interactions with pre-specified subgroups.

LIMITATIONS

Blinding of nutritional support was deemed to be impractical and, although the primary outcome was objective, some secondary outcomes, although defined and objectively assessed, may have been more vulnerable to observer bias.

CONCLUSIONS

There was no significant difference in all-cause mortality at 30 days for early nutritional support via the parenteral route compared with the enteral route among adults admitted to critical care units in England. On average, costs were higher for the parenteral route, which, combined with similar survival and quality of life, resulted in negative INBs at 1 year.

FUTURE WORK

Nutritional support is a complex combination of timing, dose, duration, delivery and type, all of which may affect outcomes and costs. Conflicting evidence remains regarding optimum provision to critically ill patients. There is a need to utilise rigorous consensus methods to establish future priorities for basic and clinical research in this area.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN17386141.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 28. See the NIHR Journals Library website for further project information.

Glucose homeostasis, nutrition and infections during critical illness

Critical illness is a complex life-threatening disease characterized by profound endocrine and metabolic alterations and by a dysregulated immune response, together contributing to the susceptibility for nosocomial infections and sepsis. Hitherto, two metabolic strategies have been shown to reduce nosocomial infections in the critically ill, namely tight blood glucose control and early macronutrient restriction. Hyperglycaemia, as part of the endocrine-metabolic responses to stress, is present in virtually all critically ill patients and is associated with poor outcome. Maintaining normoglycaemia with intensive insulin therapy has been shown to reduce morbidity and mortality, by prevention of vital organ dysfunction and prevention of new severe infections. The favourable effects of this intervention were attributed to the avoidance of glucose toxicity and mitochondrial damage in cells of vital organs and in immune cells. Hyperglycaemia was shown to impair macrophage phagocytosis and oxidative burst capacity, which could be restored by targeting normoglycaemia. An anti-inflammatory effect of insulin may have contributed to prevention of collateral damage to host tissues. Not using parenteral nutrition during the first week in intensive care units, and so accepting a large macronutrient deficit, also resulted in fewer secondary infections, less weakness and accelerated recovery. This was at least partially explained by a suppressive effect of early parenteral nutrition on autophagic processes, which may have jeopardized crucial antimicrobial defences and cell damage removal. The beneficial impact of these two metabolic strategies has opened a new field of research that will allow us to improve the understanding of the determinants of nosocomial infections, sepsis and organ failure in the critically ill.

Acquired Muscle Weakness in the Surgical Intensive Care Unit

Muscle weakness is common in the surgical intensive care unit (ICU). Low muscle mass at ICU admission is a significant predictor of adverse outcomes. The consequences of ICU-acquired muscle weakness depend on the underlying mechanism. Temporary drug-induced weakness when properly managed may not affect outcome. Severe perioperative acquired weakness that is associated with adverse outcomes (prolonged mechanical ventilation, increases in ICU length of stay, and mortality) occurs with persistent (time frame: days) activation of protein degradation pathways, decreases in the drive to the skeletal muscle, and impaired muscular homeostasis. ICU-acquired muscle weakness can be prevented by early treatment of the underlying disease, goal-directed therapy, restrictive use of immobilizing medications, optimal nutrition, activating ventilatory modes, early rehabilitation, and preventive drug therapy. In this article, the authors review the nosology, epidemiology, diagnosis, and prevention of ICU-acquired weakness in surgical ICU patients.

Nutritional support in critical illness and recovery

An adequate nutritional status is crucial for optimum function of cells and organs, and for wound healing. Options for artificial nutrition have greatly expanded in the past few decades, but have concomitantly shown limitations and potential side-effects. Few rigorous randomised controlled trials (RCTs) have investigated enteral or parenteral nutritional support, and evidence-based clinical guidance is largely restricted to the first week of critical illness. In the early stages of critical illness, whether artificial feeding is better than no feeding intervention has been given little attention in existing RCTs. Expected beneficial effects of various forms of early feeding interventions on rates of morbidity or mortality have generally not been supported by results of recent high-quality RCTs. Thus, whether nutritional interventions early in an intensive care unit (ICU) stay improve outcomes remains unclear. Trials assessing feeding interventions that continue after the first week of critical illness and into the post-ICU and post-hospital settings are clearly needed. Although acute morbidity and mortality will remain important safety parameters in such trials, primary outcomes should perhaps, in view of the adjunctive nature of nutritional intervention in critical illness, be focused on physical function and assessed months or even years after patients are discharged from the ICU. This Series paper is based on results of high-quality RCTs and provides new perspectives on nutritional support during critical illness and recovery.

Glucose management in critically ill adults and children

Blood glucose management in people with acute myocardial infarction and critical illness has always attracted controversy. Compared with the era before 2001 when no attention was given to blood glucose management, DIGAMI-1 in 1995 and the first Leuven study in 2001 showed improved outcomes with strict control of blood glucose, thereby suggesting a causal association between hyperglycaemia and mortality risk. These landmark trials have set the standard in clinical practice that excessive hyperglycaemia is not acceptable. Multicentre trials contradicted the benefits of tight control of patients' blood glucose and results showed that different standard operating procedures for blood glucose control (eg, blood glucose meters or algorithms), divergent concomitant feeding strategies, and varying patient populations are important confounders. The general consensus now is that excessive hyperglycaemia (>10 mmol/L) and severe hypoglycaemia (<2·2 mmol/L) should be avoided in critically ill adults. If adequate blood glucose meters and clinically validated protocols for insulin-dosing are available, targeting of blood glucose concentrations to less than 8 mmol/L (moderate glycaemic control), while avoiding mild hypoglycaemia (<3·9 mmol/L), is a reasonable strategy in adult patients who are critically ill. This recommendation is not based on findings from randomised controlled trials, but merely represents a very common, pragmatic approach by physicians at the bedside. As a result of the few properly validated technologies for tighter blood glucose control, targeting blood glucose concentrations to less than 6 mmol/L is not recommended, because its risk-to-benefit ratio becomes questionable. Because blood glucose control in the target of adult ranges does not improve patient outcomes for children in the intensive care unit, glucose management in this patient population should be limited to avoid excessive hyperglycaemia (>10 mmol/L).

Impact of withholding early parenteral nutrition completing enteral nutrition in pediatric critically ill patients (PEPaNIC trial): study protocol for a randomized controlled trial

Background

The state-of-the-art nutrition used for critically ill children is based essentially on expert opinion and extrapolations from adult studies or on studies in non-critically ill children. In critically ill adults, withholding parenteral nutrition (PN) during the first week in ICU improved outcome, as compared with early supplementation of insufficient enteral nutrition (EN) with PN. We hypothesized that withholding PN in children early during critical illness reduces the incidence of new infections and accelerates recovery.

Methods/Design

The Pediatric Early versus Late Parenteral Nutrition in Intensive Care Unit (PEPaNIC) study is an investigator-initiated, international, multicenter, randomized controlled trial (RCT) in three tertiary referral pediatric intensive care units (PICUs) in three countries on two continents. This study compares early versus late initiation of PN when EN fails to reach preset caloric targets in critically ill children. In the early-PN (control, standard of care) group, PN comprising glucose, lipids and amino acids is administered within the first days to reach the caloric target. In the late-PN (intervention) group, PN completing EN is only initiated beyond PICU-day 7, when EN fails. For both study groups, an early EN protocol is applied and micronutrients are administered intravenously. The primary assessor-blinded outcome measures are the incidence of new infections during PICU-stay and the duration of intensive care dependency. The sample size (n = 1,440, 720 per arm) was determined in order to detect a 5% absolute reduction in PICU infections, with at least 80% 1-tailed power (70% 2-tailed) and an alpha error rate of 5%. Based on the actual incidence of new PICU infections in the control group, the required sample size was confirmed at the time of an a priori- planned interim-analysis focusing on the incidence of new infections in the control group only.

Discussion

Clinical evidence in favor of early administration of PN in critically ill children is currently lacking, despite potential benefit but also known side effects. This large international RCT will help physicians to gain more insight in the clinical effects of omitting PN during the first week of critical illness in children.

Trial registration

ClinicalTrials.gov: NCT01536275 on 16 February 2012.

Hypocaloric compared with eucaloric nutritional support and its effect on infection rates in a surgical intensive care unit: a randomized controlled trial

BACKGROUND

Proper caloric intake goals in critically ill surgical patients are unclear. It is possible that overnutrition can lead to hyperglycemia and an increased risk of infection.

OBJECTIVE

This study was conducted to determine whether surgical infection outcomes in the intensive care unit (ICU) could be improved with the use of hypocaloric nutritional support.

DESIGN

Eighty-three critically ill patients were randomly allocated to receive either the standard calculated daily caloric requirement of 25-30 kcal · kg(-1) · d(-1) (eucaloric) or 50% of that value (hypocaloric) via enteral tube feeds or parenteral nutrition, with an equal protein allocation in each group (1.5 g · kg(-1) · d(-1)).

RESULTS

There were 82 infections in the hypocaloric group and 66 in the eucaloric group, with no significant difference in the mean (± SE) number of infections per patient (2.0 ± 0.6 and 1.6 ± 0.2, respectively; P = 0.50), percentage of patients acquiring infection [70.7% (29 of 41) and 76.2% (32 of 42), respectively; P = 0.57], mean ICU length of stay (16.7 ± 2.7 and 13.5 ± 1.1 d, respectively; P = 0.28), mean hospital length of stay (35.2 ± 4.9 and 31.0 ± 2.5 d, respectively; P = 0.45), mean 0600 glucose concentration (132 ± 2.9 and 135 ± 3.1 mg/dL, respectively; P = 0.63), or number of mortalities [3 (7.3%) and 4 (9.5%), respectively; P = 0.72]. Further analyses revealed no differences when analyzed by sex, admission diagnosis, site of infection, or causative organism.

CONCLUSIONS

Among critically ill surgical patients, caloric provision across a wide acceptable range does not appear to be associated with major outcomes, including infectious complications. The optimum target for caloric provision remains elusive.

Timing of (supplemental) parenteral nutrition in critically ill patients: a systematic review

Supplemental parenteral nutrition (SPN) is used in a step-up approach when full enteral support is contraindicated or fails to reach caloric targets. Recent nutrition guidelines present divergent advices regarding timing of SPN in critically ill patients ranging from early SPN (<48 h after admission; EPN) to postponing initiation of SPN until day 8 after Intensive Care Unit (ICU) admission (LPN). This systematic review summarizes results of prospective studies among adult ICU patients addressing the best timing of (supplemental) parenteral nutrition (S)PN. A structured PubMed search was conducted to identify eligible articles. Articles were screened and selected using predetermined criteria and appraised for relevance and validity. After critical appraisal, four randomized controlled trials (RCTs) and two prospective observational studies remained. One RCT found a higher percentage of alive discharge from the ICU at day 8 in the LPN group compared to EPN group (p = 0.007) but no differences in ICU and in-hospital mortality. None of the other RCTs found differences in ICU or in-hospital mortality rates. Contradicting or divergent results on other secondary outcomes were found for ICU length of stay, hospital length of stay, infection rates, nutrition targets, duration of mechanical ventilation, glucose control, duration of renal replacement therapy, muscle wasting and fat loss. Although the heterogeneity in quality and design of relevant studies precludes firm conclusions, it is reasonable to assume that in adult critically ill patients, there are no clinically relevant benefits of EPN compared with LPN with respect to morbidity or mortality end points, when full enteral support is contraindicated or fails to reach caloric targets. However, considering that infectious morbidity and resolution of organ failure may be negatively affected through mechanisms not yet clearly understood and acquisition costs of parenteral nutrition are higher, the early administration of parenteral nutrition cannot be recommended.

Acute outcomes and 1-year mortality of intensive care unit-acquired weakness. A cohort study and propensity-matched analysis

RATIONALE

Intensive care unit (ICU)-acquired weakness is a frequent complication of critical illness. It is unclear whether it is a marker or mediator of poor outcomes.

OBJECTIVES

To determine acute outcomes, 1-year mortality, and costs of ICU-acquired weakness among long-stay (≥8 d) ICU patients and to assess the impact of recovery of weakness at ICU discharge.

METHODS

Data were prospectively collected during a randomized controlled trial. Impact of weakness on outcomes and costs was analyzed with a one-to-one propensity-score-matching for baseline characteristics, illness severity, and risk factor exposure before assessment. Among weak patients, impact of persistent weakness at ICU discharge on risk of death after 1 year was examined with multivariable Cox proportional hazards analysis.

MEASUREMENTS AND MAIN RESULTS

A total of 78.6% were admitted to the surgical ICU; 227 of 415 (55%) long-stay assessable ICU patients were weak; 122 weak patients were matched to 122 not-weak patients. As compared with matched not-weak patients, weak patients had a lower likelihood for live weaning from mechanical ventilation (hazard ratio [HR], 0.709 [0.549-0.888]; P = 0.009), live ICU (HR, 0.698 [0.553-0.861]; P = 0.008) and hospital discharge (HR, 0.680 [0.514-0.871]; P = 0.007). In-hospital costs per patient (+30.5%, +5,443 Euro per patient; P = 0.04) and 1-year mortality (30.6% vs. 17.2%; P = 0.015) were also higher. The 105 of 227 (46%) weak patients not matchable to not-weak patients had even worse prognosis and higher costs. The 1-year risk of death was further increased if weakness persisted and was more severe as compared with recovery of weakness at ICU discharge (P < 0.001).

CONCLUSIONS

After careful matching the data suggest that ICU-acquired weakness worsens acute morbidity and increases healthcare-related costs and 1-year mortality. Persistence and severity of weakness at ICU discharge further increased 1-year mortality. Clinical trial registered with www.clinicaltrials.gov (NCT 00512122).

Withholding parenteral nutrition during critical illness increases plasma bilirubin but lowers the incidence of biliary sludge

Cholestatic liver dysfunction (CLD) and biliary sludge often occur during critical illness and are allegedly aggravated by parenteral nutrition (PN). Delaying initiation of PN beyond day 7 in the intensive care unit (ICU) (late PN) accelerated recovery as compared with early initiation of PN (early PN). However, the impact of nutritional strategy on biliary sludge and CLD has not been fully characterized. This was a preplanned subanalysis of a large randomized controlled trial of early PN versus late PN (n = 4,640). In all patients plasma bilirubin (daily) and liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST], gamma-glutamyl transpeptidase [GGT], alkaline phosphatase [ALP], twice weekly; n = 3,216) were quantified. In a random predefined subset of patients, plasma bile acids (BAs) were also quantified at baseline and on days 3, 5, and last ICU-day (n = 280). Biliary sludge was ultrasonographically evaluated on ICU-day 5 (n = 776). From day 1 after randomization until the end of the 7-day intervention window, bilirubin was higher in the late PN than in the early PN group (P < 0.001). In the late PN group, as soon as PN was started on day 8 bilirubin fell and the two groups became comparable. Maximum levels of GGT, ALP, and ALT were lower in the late PN group (P < 0.01). Glycine/taurine-conjugated primary BAs increased over time in ICU (P < 0.01), similarly for the two groups. Fewer patients in the late PN than in the early PN group developed biliary sludge on day 5 (37% versus 45%; P = 0.04).

CONCLUSION

Tolerating substantial caloric deficit by withholding PN until day 8 of critical illness increased plasma bilirubin but reduced the occurrence of biliary sludge and lowered GGT, ALP, and ALT. These results suggest that hyperbilirubinemia during critical illness does not necessarily reflect cholestasis and instead may be an adaptive response that is suppressed by early PN.

Year in review 2012: Critical Care--management

Outcomes research plays a key role in defining the effects of medical care in critical care. Last year Critical Care published a number of papers that evaluated patient-centered and policy-relevant outcomes. We present this review article focusing on key reported outcomes associated with severe community-acquired pneumonia, mortality associated with decisions regarding triage to the ICU, and both short-term and long-term mortality associated with ICU admissions. We further analyze the literature, assessing outcomes such as quality of life and the psychological burden associated with critical care. We also reviewed processes of care, and studies looking at cost analysis of treatment associated with critical care.

Early parenteral nutrition in critically ill patients with short-term relative contraindications to early enteral nutrition: a full economic analysis of a multicenter randomized controlled trial based on US costs

Purpose

The provision of early enteral (gut) nutrition to critically ill patients, started within 24 hours of injury or intensive care unit admission, is accepted to improve health outcomes. However, not all patients are able to receive early enteral nutrition. The purpose of the economic analysis presented here was to estimate the cost implications of providing early parenteral (intravenous) nutrition to critically ill patients with short-term relative contraindications to early enteral nutrition.

Materials and methods

From the perspective of the US acute care hospital system, a cost-minimization analysis was undertaken based on large-scale Monte Carlo simulation (N = 1,000,000 trials) of a stochastic model developed using clinical outcomes and measures of resource consumption reported in a 1,363-patient multicenter clinical trial combined with cost distributions obtained from the published literature. The mean costs of acute care attributable to each study group (early parenteral nutrition versus pragmatic standard care) and the mean cost difference between groups, along with respective 95% confidence intervals, were obtained using the percentile method.

Results and conclusion

The use of early parenteral nutrition in critically ill patients with short-term relative contraindications to early enteral nutrition may significantly and meaningfully reduce total costs of acute hospital care by US$3,150 per patient (95% confidence interval US$1,314 to US$4,990). These findings were robust, with all sensitivity analyses demonstrating significant savings attributable to the use of early parenteral nutrition, including sensitivity analysis conducted using European cost data.

LOGIC-insulin algorithm-guided versus nurse-directed blood glucose control during critical illness: the LOGIC-1 single-center, randomized, controlled clinical trial

OBJECTIVE

Tight blood glucose control (TGC) in critically ill patients is difficult and labor intensive, resulting in poor efficacy of glycemic control and increased hypoglycemia rate. The LOGIC-Insulin computerized algorithm has been developed to assist nurses in titrating insulin to maintain blood glucose levels at 80-110 mg/dL (normoglycemia) and to avoid severe hypoglycemia (<40 mg/dL). The objective was to validate clinically LOGIC-Insulin relative to TGC by experienced nurses.

RESEARCH DESIGN AND METHODS

The investigator-initiated LOGIC-1 study was a prospective, parallel-group, randomized, controlled clinical trial in a single tertiary referral center. A heterogeneous mix of 300 critically ill patients were randomized, by concealed computer allocation, to either nurse-directed glycemic control (Nurse-C) or algorithm-guided glycemic control (LOGIC-C). Glycemic penalty index (GPI), a measure that penalizes both hypoglycemic and hyperglycemic deviations from normoglycemia, was the efficacy outcome measure, and incidence of severe hypoglycemia (<40 mg/dL) was the safety outcome measure.

RESULTS

Baseline characteristics of 151 Nurse-C patients and 149 LOGIC-C patients and study times did not differ. The GPI decreased from 12.4 (interquartile range 8.2-18.5) in Nurse-C to 9.8 (6.0-14.5) in LOGIC-C (P < 0.0001). The proportion of study time in target range was 68.6 ± 16.7% for LOGIC-C patients versus 60.1 ± 18.8% for Nurse-C patients (P = 0.00016). The proportion of severe hypoglycemic events was decreased in the LOGIC-C group (Nurse-C 0.13%, LOGIC-C 0%; P = 0.015) but not when considered as a proportion of patients (Nurse-C 3.3%, LOGIC-C 0%; P = 0.060). Sampling interval was 2.2 ± 0.4 h in the LOGIC-C group versus 2.5 ± 0.5 h in the Nurse-C group (P < 0.0001).

CONCLUSIONS

Compared with expert nurses, LOGIC-Insulin improved efficacy of TGC without increasing rate of hypoglycemia.

Role of disease and macronutrient dose in the randomized controlled EPaNIC trial: a post hoc analysis

RATIONALE

Early parenteral nutrition to supplement insufficient enteral feeding during intensive care (early PN) delays recovery as compared with withholding parenteral nutrition for 1 week (late PN).

OBJECTIVES

To assess whether deleterious effects of early PN relate to severity of illness or to the dose or type of macronutrients.

METHODS

Secondary analyses of a randomized controlled trial (EPaNIC; n = 4,640) performed in seven intensive care units from three departments in two Belgian hospitals. In part 1, all patients were included to assess the effect of the randomized allocation to early PN or late PN in subgroups of patients with increasing-on-admission severity of illness. In part 2, observationally, the association of the amount and type of macronutrients with recovery was documented in those patient cohorts still present in intensive care on Days 3, 5, 7, 10, and 14.

MEASUREMENTS AND MAIN RESULTS

The primary end point was time to live discharge from the intensive care unit. For part 1, a secondary end point, acquisition of new infections, was also analyzed. All statistical analyses were performed by univariable and adjusted multivariable methods. In none of the subgroups defined by type or severity of illness was a beneficial effect of early PN observed. The lowest dose of macronutrients was associated with the fastest recovery and any higher dose, administered parenterally or enterally, was associated with progressively more delayed recovery. The amount of proteins/amino acids rather than of glucose appeared to explain delayed recovery with early feeding.

CONCLUSIONS

Early combined parenteral/enteral nutrition delayed recovery irrespective of severity of critical illness. No dose or type of macronutrient was found to be associated with improved outcome. Clinical trial registered with www.clinicaltrials.gov (NCT 00512122).