The Metabolic Response to Stress and Infection in Critically Ill Children: The Opportunity of an Individualized Approach

Eu- or hypoglycemic ketosis and ketoacidosis in children: a review

The last decade has been characterized by exciting findings on eu- or hypoglycemic ketosis and ketoacidosis. This review emphasizes the following five key points: 1. Since the traditional nitroprusside-glycine dipstick test for urinary ketones is often falsely negative, the blood determination of β-hydroxybutyrate, the predominant ketone body, is currently advised for a comprehensive assessment of ketone body status; 2. Fasting and infections predispose to relevant ketosis and ketoacidosis especially in newborns, infants, children 7 years or less of age, and pregnant, parturient, or lactating women; 3. Several forms of carbohydrate restriction (typically less than 20% of the daily caloric intake) are employed to induce ketosis. These ketogenic diets have achieved great interest as antiepileptic treatment, in the management of excessive body weight, diabetes mellitus, and in sport training; 4. Intermittent fasting is more and more popular because it might benefit against cardiovascular diseases, cancers, neurologic disorders, and aging; 5. Gliflozins, a new group of oral antidiabetics inhibiting the renal sodium-glucose transporter 2, are an emerging cause of eu- or hypoglycemic ketosis and ketoacidosis. In conclusion, the role of ketone bodies is increasingly recognized in several clinical conditions. In the context of acid-base balance evaluation, it is advisable to routinely integrate both the assessment of lactic acid and β-hydroxybutyrate.

Validation of Indirect Calorimetry in Children Undergoing Single-Limb Non-Invasive Ventilation: A Proof of Concept, Cross-Over Study

BACKGROUND

The accurate assessment of resting energy expenditure (REE) is essential for personalized nutrition, particularly in critically ill children. Indirect calorimetry (IC) is the gold standard for measuring REE. This methodology is based on the measurement of oxygen consumption (VO2) and carbon dioxide production (VCO2). These parameters are integrated into the Weir equation to calculate REE. Additionally, IC facilitates the determination of the respiratory quotient (RQ), offering valuable insights into a patient's carbohydrate and lipid consumption. IC validation is limited to spontaneously breathing and mechanically ventilated patients, but it is not validated in patients undergoing non-invasive ventilation (NIV). This study investigates the application of IC during NIV-CPAP (continuous positive airway pressure) and NIV-PS (pressure support).

METHODS

This study was conducted in the Pediatric Intensive Care Unit of IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, between 2019 and 2021. Children < 6 years weaning from NIV were enrolled. IC was performed during spontaneous breathing (SB), NIV-CPAP, and NIV-PS in each patient. A Bland-Altman analysis was employed to compare REE, VO2, VCO2, and RQ measured by IC.

RESULTS

Fourteen patients (median age 7 (4; 18) months, median weight 7.7 (5.5; 9.7) kg) were enrolled. The REE, VO2, VCO2, and RQ did not differ significantly between the groups. The Limits of Agreement (LoA) and bias of REE indicated good agreement between SB and NIV-CPAP (LoA +28.2, -19.4 kcal/kg/day; bias +4.4 kcal/kg/day), and between SB and NIV-PS (LoA -22.2, +23.1 kcal/kg/day; bias 0.4 kcal/kg/day).

CONCLUSIONS

These preliminary findings support the accuracy of IC in children undergoing NIV. Further validation in a larger cohort is warranted.

Body composition in pediatric patients

Undernutrition is highly prevalent in children who are critically ill and is associated with increased morbidity and mortality, including a higher risk of infection due to transitory immunological disorders, inadequate wound healing, reduced gut function, longer dependency on mechanical ventilation, and longer hospital stays compared with eutrophic children who are critically ill. Nutrition care studies have proposed that early interventions targeting nutrition assessment can prevent or minimize the complications of undernutrition. Stress promotes an acute inflammatory response mediated by cytokines, resulting in increased basal metabolism and nitrogen excretion and leading to muscle loss and changes in body composition. Therefore, the inclusion of body composition assessment is important in the evaluation of these patients because, in addition to the nutrition aspect, body composition seems to predict clinical prognosis. Several techniques can be used to assess body composition, such as arm measurements, calf circumference, grip strength, bioelectrical impedance analysis, and imaging examinations, including computed tomography and dual-energy x-ray absorptiometry. This review of available evidence suggests that arm measurements seem to be well-established in assessing body composition in children who are critically ill, and that bioelectrical impedance analysis with phase angle, handgrip strength, calf circumference and ultrasound seem to be promising in this evaluation. However, further robust studies based on scientific evidence are necessary.

Nutritional support in the critical ill patient: Requirements, prescription and adherence

INTRODUCTION

In critically ill patients, nutritional support is a challenge in terms of both estimating their requirements and ensuring adherence to the prescribed treatment.

OBJECTIVE

To assess the association between requirements, prescription and adherence to energy and protein supplementation based on the phase of disease in critically ill patients.

SAMPLE AND METHODS

We conducted a prospective, observational and analytical study in patients aged 0-18 years admitted to the paediatric intensive or intermediate care unit in 2020-2021. We collected data on demographic and anthropometric characteristics and the phase of disease (acute phase [AP] vs. non-acute phase [nAP]), in addition to prescribing (P) (indication of nutritional support), basal metabolic rate (BMR, Schofield equation), adherence to nutritional support (A) and protein requirements (R), and calculated the following ratios: P/BMR, P/R, A/BMR, A/R, and A/P.

RESULTS

The sample included 131 participants with a median age of 16 (4.5) months, of who 128 (97.7%) had comorbidities and 13 (9.9%) were in the AP. Comparing the phases of disease (AP vs. nAP), the median values for energy supplementation were P/BMR, 0.5 (IQR, 0.1-1.4) vs. 1.3 (IQR, 0.9-1.8) (P = 0.0054); A/BMR, 0.4 (IQR, 0-0.6) vs. 1.2 (IQR, 0.8-1.7) (P = 0.0005); A/P, 0.7 (IQR, 0-0.9) vs. 1 (IQR, 0.8-1) (P = 0.002), and for protein were P/R, 0.7 (IQR, 0-1.1) vs. 1.2 (0.9-1.6) (P = 0.0009); A/R 0.3 (IQR, 0-0.6) vs. 1.1 (IQR, 0.8-1.5) (P = 0.0002); A/P 0.7 (IQR, 0-1) vs. 1(IQR, 0.8-1) (P = 0.002). We found AP/nAP ratios greater than 110% for energy in the P/BMR (4 patients [30.8%]/72 patients [61%]; P = 0.007), A/BMR (3 [23%]/63 [53.4%]; P = 0.009) and A/P (1 [7%]/3 [2.5%]; P = 0.007). As for protein, more than 1.5 g/kg/day was prescribed in 3 patients (23.1%) in the AP and 71 (60.1%) in the nAP. We found adherence to the prescribed intake in 2 (15.4%) patients in the AP and 66 (56%) in the nAP. We found a correlation coefficient of 0.6 between the energy P/R and the protein P/R. Prescribed support was discontinued in 7 patients (53.8%) in the AP and 31 (26.3%) in the nAP (P = 0.002).

CONCLUSIONS

The proportion of adherence to prescribed nutritional support was high in patients in the nAP of the disease. Overfeeding was frequent, more so in the nAP. We identified difficulties in adhering to prescribed support, chief of which was the discontinuation of feeding.

3-Hydroxybutyrate ameliorates sepsis-associated acute lung injury by promoting autophagy through the activation of GPR109α in macrophages

BACKGROUND

Sepsis is a systemic inflammatory disease caused by multiple pathogens, with the most commonly affected organ being the lung. 3-Hydroxybutyrate plays a protective role in inflammatory diseases through autophagy promotion; however, the exact mechanism remains unexplored.

METHOD

Our study used the MIMIC-III database to construct a cohort of ICU sepsis patients and figure out the correlation between the level of ketone bodies and clinical prognosis in septic patients. In vivo and in vitro models of sepsis were used to reveal the role and mechanism of 3-hydroxybutyrate in sepsis-associated acute lung injury (sepsis-associated ALI).

RESULT

Herein, we observed a strong correlation between the levels of ketone bodies and clinical prognosis in patients with sepsis identified using the MIMIC- III database. In addition, exogenous 3-hydroxybutyrate supplementation improved the survival rate of CLP-induced sepsis in mice by promoting autophagy. Furthermore, 3-hydroxybutyrate treatment protected against sepsis-induced lung damage. We explored the mechanism underlying these effects. The results indicated that 3-hydroxybutyrate upregulates autophagy levels by promoting the transfer of transcription factor EB (TFEB) to the macrophage nucleus in a G-protein-coupled receptor 109 alpha (GPR109α) dependent manner, upregulating the transcriptional level of ultraviolet radiation resistant associated gene (UVRAG) and increasing the formation of autophagic lysosomes.

CONCLUSION

3-Hydroxybutyrate can serve as a beneficial therapy for sepsis-associated ALI through the upregulation of autophagy. These results may provide a basis for the development of promising therapeutic strategies for sepsis-associated ALI.

Is Undernutrition Associated With Deterioration of Outcomes in the Pediatric Intensive Care Unit (PICU): Systematic and Meta-Analysis Review

BACKGROUND AND AIM

Undernutrition (UN) may negatively impact clinical outcomes for hospitalized patients. The relationship between UN status at pediatric intensive care unit (PICU) admission and clinical outcomes is still not well-reported. This systematic meta-analysis review evaluated the impact of UN at admission to PICU on clinical outcomes, including mortality incidence, length of stay (LOS), and the need for and length of time on mechanical ventilation (MV).

METHODS

A search was conducted using relevant and multi-medical databases from inception until January 2022. We considered studies that examined the link between UN at PICU admission and clinical outcomes in patients aged 18 years or younger. Pooled risk difference estimates for the PICU outcomes were calculated using a random-effects model.

RESULT

There were a total of 10,638 patients included in 17 observational studies; 8,044 (75.61%) and 2,594 (24.38%) patients, respectively, were normal-nourished (NN) and undernourished (UN). In comparison to NN patients, UN patients had a slightly higher risk of mortality (RD = 0.02, P = 0.05), MV usage (RD = 0.05, P = 0.02), and PICU LOS (RD = 0.07, P = 0.007). While the duration of MV was significantly longer in UN than in NN (RD = 0.13, P < 0.0001). Sensitivity analysis of UN classification cohorts with a z-score < -2 or in the 5%, patetints age up to 18 years, and mixed diagnose for PICU admission demonstrated a 6-fold increase in the probability of PICU LOS in UN patients compared to NN patients (RD = 0.06, 95% CI = 0.01, 0.12). UN patients have a higher risk of MV usage RD = 0.07, 95% CI = 0.00, 0.14) in studies involving cohorts with a mixed primary diagnosis for PICU admission.

CONCLUSION

In PICU, UN is linked to mortality incidence, longer PICU stay, MV usage, and duration on MV. The primary diagnosis for PICU admission may also influence clinical outcomes. Determining the prevalence of UN in hospitalized patients, as well as the subgroups of patients diagnosed at the time of admission, requires more research. This may help explain the relationship between nutritional status and clinical outcomes in PICU patients.

Artificial Neural Network Algorithms to Predict Resting Energy Expenditure in Critically Ill Children

INTRODUCTION

Accurate assessment of resting energy expenditure (REE) can guide optimal nutritional prescription in critically ill children. Indirect calorimetry (IC) is the gold standard for REE measurement, but its use is limited. Alternatively, REE estimates by predictive equations/formulae are often inaccurate. Recently, predicting REE with artificial neural networks (ANN) was found to be accurate in healthy children. We aimed to investigate the role of ANN in predicting REE in critically ill children and to compare the accuracy with common equations/formulae.

STUDY METHODS

We enrolled 257 critically ill children. Nutritional status/vital signs/biochemical values were recorded. We used IC to measure REE. Commonly employed equations/formulae and the VCO₂-based Mehta equation were estimated. ANN analysis to predict REE was conducted, employing the TWIST system.

RESULTS

ANN considered demographic/anthropometric data to model REE. The predictive model was good (accuracy 75.6%; R² = 0.71) but not better than Talbot tables for weight. After adding vital signs/biochemical values, the model became superior to all equations/formulae (accuracy 82.3%, R² = 0.80) and comparable to the Mehta equation. Including IC-measured VCO₂ increased the accuracy to 89.6%, superior to the Mehta equation.

CONCLUSIONS

We described the accuracy of REE prediction using models that include demographic/anthropometric/clinical/metabolic variables. ANN may represent a reliable option for REE estimation, overcoming the inaccuracies of traditional predictive equations/formulae.

Metabolism and energy prescription in critically III children

Optimal nutrition therapy can positively influence clinical outcomes in critically ill children. Accurate assessment of nutritional status, metabolic state, macronutrient requirements and substrate utilization allows accurate prescription of nutrition in this population. In response to stress and injury, the body undergoes adaptive physiologic changes leading to dysregulation of the inflammatory response and hyperactivation of the inflammatory cascade. This results in a global catabolic state with modification in oxygen consumption and macronutrient metabolism. A comprehensive understanding of the metabolic response is essential when prescribing nutritional interventions aimed to offset the burden of this adaptive stress response in the critically ill. In this narrative review we aim to provide a comprehensive review of the physiologic basis, recent literature and some emerging concepts related to energy expenditure and the practical aspects of energy delivery in the critically ill child. Based on the unique metabolic characteristics of the critically ill child, we aim to provide a pragmatic approach to providing nutrition therapy.

Iatrogenic severe hyperglycemia due to parenteral administration of glucose in children - a case series

Background

Iatrogenic severe hyperglycemia (ISH) caused by glucose-containing i.v. solution is a potentially fatal treatment error. The objective of this study was to investigate the causes, circumstances, course of disease, and complications of ISH > 300 mg/dl (16.7 mmol/l) in neonates and children.

Methods

We emailed a survey to 105 neonatal and pediatric intensive care units in Germany, Austria, and Switzerland, asking to retrospectively report cases of ISH.

Results

We received 11 reports about premature infants to children. Four patients (36%) had poor outcome: 2 died and 2 suffered persistent sequelae. The highest observed blood glucose was at median 983 mg/dl (54.6 mmol/l) (range 594–2240 mg/dl; 33.0–124.3 mmol/l) and median time to normoglycemia was 7 h (range 2–23). Blood glucose was higher and time to normoglycemia longer in patients with poor outcome. Invasive therapy was required in 73% (mechanical ventilation) and 50% (vasopressor therapy) of patients, respectively. Administration of insulin did not differ between outcome groups. Patients with poor outcome showed coma (100% vs. 40%) and seizures (75% vs. 29%) more frequently than those with good outcome.

Conclusions

ISH is a severe condition with high morbidity and mortality. Further research to amplify the understanding of this condition is needed, but focus should largely be held on its prevention.

Persistent inflammation, immunosuppression and catabolism syndrome (PICS) in critically ill children is associated with clinical outcomes: a prospective longitudinal study

BACKGROUND

Persistent inflammation, immunosuppression and catabolism syndrome (PICS) has been described in critically ill adults and may contribute to unfavourable outcomes. The present study aimed to describe and characterise PICS in critically ill children (PICS-ped) and to verify its association with clinical outcomes.

METHODS

A prospective longitudinal study was conducted in a paediatric intensive care unit (PICU) with children aged between 3 months and 15 years. PICS-ped, based on adult definition, was described. PICS-ped was defined as PICU length of stay >14 days; C-reactive protein > 10.0 mg L^-1 ; lymphocytes <25%; and any reduction of mid-upper arm circumference Z-score. Clinical, demographic, nutritional status, nutrition therapy parameters and clinical outcomes were assessed. Statistical analysis comprised Mann-Whitney and Fisher's chi-squared tests, as well as logistic and Cox regression. P < 0.05 was considered statistically significant.

RESULTS

In total, 153 children were included, with a median age of 51.7 months (interquartile range 15.6-123.4 months), and 60.8% male. The mortality rate was 10.5%. The prevalence of PICS-ped was 4.6%. Days using vasoactive drugs and days using antibiotics were associated with PICS-ped. PICS-ped was associated with mortality in crude (odds ratio = 6.67; P = 0.013) and adjusted analysis (odds ratio = 7.14; P = 0.017). PICS-ped was also associated with PICU and hospital length of stay, as well as duration of mechanical ventilation. Similar results were found in a subset of critically ill children who required mechanical ventilation for more than 48 h.

CONCLUSIONS

Children with PICS-ped required antibiotics or vasoactive drugs for a longer period. PICS-ped was associated with poor clinical outcomes in critically ill children. More studies are needed to properly define PICS-ped for this population.

Clinical Outcomes in Critically Ill Children With Excess Weight: A Retrospective Cohort Study

BACKGROUND

Because of its high prevalence and negative impact on quality of life and longevity, overweight in childhood and adolescence is a major public health concern. The objective of the present study was to determine whether excess weight is associated with clinical outcomes in critically ill children and adolescents admitted to the pediatric intensive care unit (PICU).

METHOD

This retrospective cohort study was performed with children and adolescents admitted to a PICU over 3 years. Nutrition status was classified based on the body mass index z-score for age, following World Health Organization (WHO) criteria. The following outcomes were assessed: mortality, need for mechanical ventilation, length of admission, and multiple organ dysfunction syndrome.

RESULTS

Of 1468 patients admitted during the study period, 1407 were included in the study: 956 (68.0%) had adequate weight, 228 (16.2%) were overweight, and 223 (15.8%) were underweight. Associations were detected between most variables and all nutrition categories (underweight, adequate weight, and overweight). In the descriptive analysis, mortality was more prevalent in nutrition status extremes (extremely underweight or overweight). An independent association between nutrition status and mortality was not detected in any category.

CONCLUSION

Nutrition status was not independently associated with poor outcomes. However, overweight should be considered a potential risk factor for adverse clinical outcomes in PICU admissions.

Micronutrient status during paediatric critical illness: A scoping review

Background

No evidence based recommendations for micronutrient requirements during paediatric critical illness are available, other than those arising from recommended nutrient intakes (RNI) for healthy children and expert opinion.

Objectives

The objective of this review is to examine the available evidence from micronutrient status in critically ill children considering studies which describe 1) micronutrient levels, 2) associations between micronutrient levels and clinical outcome, and 3) impact on clinical outcome with micronutrient supplementation during PICU admission.

Design

Scoping review.

Eligibility criteria

Any study which used a qualitative and quantitative design considering causes and consequences of micronutrient levels or micronutrient supplementation during paediatric critical illness.

Sources of evidence

NICE Healthcare Databases Advanced Search website (https://hdas.nice.org.uk/) was used as a tool for multiple searches, with a content analysis and charting of data extracted.

Results

711 records were identified, 35 were included in the review. Studies evaluated serum micronutrient status was determined on admission day in majority of patients. A content analysis identified (n = 49) initial codes, (n = 14) sub-categories and (n = 5) overarching themes during critical illness, which were identified as: i) low levels of micronutrients, ii) causes of aberrant micronutrient levels, iii) associations between micronutrients levels and outcome, iv) supplementation of micronutrients.

Conclusion

During critical illness, micronutrients should be provided in sufficient amounts to meet reference nutrient intakes for age. Although, there is insufficient data to recommend routine supplementations of micronutrients at higher doses during critical illness, the ‘absence of evidence should not imply evidence of absence’, and well designed prospective studies are urgently needed to elucidate paediatric micronutrient requirements during critical illness. The absence of reliable biomarkers make it challenging to determine whether low serum levels are reflective of a true deficiency or as a result redistribution, particularly during the acute phase of critical illness. As more children continue to survive a PICU admission, particularly those with complex diseases micronutrient supplementation research should also be inclusive of the recovery phase following critical illness.

Resting Energy Expenditure and Protein Balance in People with Epidermolysis Bullosa

Epidermolysis bullosa (EB) is a group of conditions characterized by severe fragility of the skin that causes recurring blistering. The recessive dystrophic subtype of EB (RDEB) has a strong impact on the nutritional status. We evaluated the resting energy expenditure (REE) and presence of protein catabolism in patients with RDEB. REE was assessed in 10 subjects (7 females; age range 4-33 years) by indirect calorimetry and using a predictive equation. Nitrogen balance was calculated by protein intake and 24 h urinary urea excretion estimations. An assessment of body surface area (BSA) with infected and non-infected skin lesions was applied to the nitrogen balance burn equation that was adapted to EB. The REE values predicted by the equation were consistently lower than the ones measured, except for two subjects. All subjects recorded high protein and energy intake, with protein intake being higher than 4 g protein/kg/day for five subjects. Even so, protein catabolism was observed in six subjects, three of whom had infected wounds. This study raises the hypothesis that the clinical and nutritional risks of people with RDEB are associated with an increased REE and negative nitrogen balance, which reinforces the importance of nutritional support.

A nutrition-based approach to epidermolysis bullosa: Causes, assessments, requirements and management

Inherited epidermolysis bullosa (EB) is a clinically and genetically heterogeneous group of rare diseases characterized by skin and mucous membrane fragility. EB primarily involves the skin and, in specific subtypes, the mucous membrane, resulting in complications which can strongly affect nutritional status (e.g. gastrointestinal complications, hand deformities, pain). The aims of nutritional support mainly include improving nutritional status, alleviating the stress of oral feeding and minimizing nutritional deficiencies, thus consequently improving growth, pubertal development, bowel function, immune status and wound healing. The aim of this review is to discuss knowledge of different aspects of the disease related to nutrition and growth.

Nutrients, Infectious and Inflammatory Diseases

A balanced diet with sufficient essential nutritional elements is critical for maintaining a healthy body.[...].