Cytokines and metabolic patterns in pediatric patients with critical illness

Association of anthropometric z score with complications and length of hospital stay in children with severe pneumonia aged 3 months to 5 years

BACKGROUND

Severe pneumonia in children accounts for a significant healthcare burden, involving prolonged hospitalization and increased risk of complications. The prognosis is closely related to the child's nutrition status. Anthropometric z scores are preferred to evaluate growth levels in children. This study aimed to investigate the association of anthropometric z scores with complications and length of hospital stay (LOS) in children with severe pneumonia.

METHODS

This study included 361 hospitalized children aged 3 months to 5 years with severe pneumonia in Tianjin, China. Anthropometry was performed, and anthropometric z scores were calculated. Blood laboratory indices were assessed, and complications and LOS were recorded.

RESULTS

The average anthropometric z scores were -0.10 ± 1.15 (body mass index for age z score), 0.00 ± 0.97 (upper arm circumference for age z score [ACAZ]), and -0.14 ± 1.00 (triceps skinfold thickness for age z score [TSAZ]). The prevalence of complications was 73.96% (n = 267), including 82 children with only respiratory complications, 71 with only extrapulmonary complications, and 114 with both. After adjusting for confounding factors, compared with the noncomplication group, only the extrapulmonary complication group had a lower TSAZ (odds ratio [OR] = 0.597; 95% CI = 0.405-0.880; P < 0.05), whereas the respiratory and extrapulmonary complication group had a lower ACAZ (OR = 0.674; 95% CI = 0.469-0.969; P < 0.05) and TSAZ (OR = 0.573; 95% CI = 0.389-0.843; P < 0.05). ACAZ (β = -0.368; 95% CI = -0.720 to 0.016; P < 0.05) and TSAZ (β = -1.123; 95% CI = -1.470 to -0.777; P < 0.05) were negatively correlated with LOS.

CONCLUSION

ACAZ and TSAZ were associated with complications and LOS of severe pneumonia in children aged 3 months to 5 years.

Role of Nuclear Factor-Kappa B Activation and Inflammatory Biomarkers in Critically Ill Children

Mortality prediction is important for cautious monitoring and optimal management of critically ill children. The serum cytokine levels are elevated early in critical illness before the physiological parameters are deranged. This cross-sectional descriptive study included the critically ill children admitted in intensive care unit. Serial serum levels of IL-6, NF-κB and PELOD 2 scoring were measured and compared in 45 children (40 survivors, 5 non-survivors). The median IL-6 levels at 24 h and 72 h were significantly high in non-survivors when compared to survivors [median (IQR) = 1122 (1305) pg/ml vs. 564.39 (153) pg/ml and 1263 (626) pg/ml vs. 82 (191) pg/ml respectively; p <0.0001)]. There was an increasing trend of IL-6 in non-survivors when compared to the survivors. The NF-κB values were comparable. The IL-6 levels correlated well with the illness severity. IL-6 had superior prognostic value compared with NF-κB in predicting mortality.

Nonpulmonary Treatments for Pediatric Acute Respiratory Distress Syndrome: From the Second Pediatric Acute Lung Injury Consensus Conference

OBJECTIVES

To provide an updated review of the literature on nonpulmonary treatments for pediatric acute respiratory distress syndrome (PARDS) from the Second Pediatric Acute Lung Injury Consensus Conference.

DATA SOURCES

MEDLINE (Ovid), Embase (Elsevier), and CINAHL Complete (EBSCOhost).

STUDY SELECTION

Searches were limited to children with PARDS or hypoxic respiratory failure focused on nonpulmonary adjunctive therapies (sedation, delirium management, neuromuscular blockade, nutrition, fluid management, transfusion, sleep management, and rehabilitation).

DATA EXTRACTION

Title/abstract review, full-text review, and data extraction using a standardized data collection form.

DATA SYNTHESIS

The Grading of Recommendations Assessment, Development, and Evaluation approach was used to identify and summarize evidence and develop recommendations. Twenty-five studies were identified for full-text extraction. Five clinical practice recommendations were generated, related to neuromuscular blockade, nutrition, fluid management, and transfusion. Thirteen good practice statements were generated on the use of sedation, iatrogenic withdrawal syndrome, delirium, sleep management, rehabilitation, and additional information on neuromuscular blockade and nutrition. Three research statements were generated to promote further investigation in nonpulmonary therapies for PARDS.

CONCLUSIONS

These recommendations and statements about nonpulmonary treatments in PARDS are intended to promote optimization and consistency of care for patients with PARDS and identify areas of uncertainty requiring further investigation.

Measuring the Resting Energy Expenditure in Children on Extracorporeal Membrane Oxygenation: A Prospective Pilot Study

Both overfeeding and underfeeding critically ill children are problematic. This prospective pilot study evaluated the resting energy expenditure in infants and children requiring extracorporeal membrane oxygenation (ECMO) support. An indirect calorimeter was used to measure oxygen consumption (VO 2 ) and carbon dioxide production (VCO 2 ) from the mechanical ventilator. Blood gases were used to determine VO 2 and VCO 2 from the ECMO circuit. Values from the mechanical ventilator and ECMO circuit were added, and the resting energy expenditure (REE) (Kcal/kg/day) was calculated. Measurements were obtained > 24 hours after ECMO support was initiated (day 2 of ECMO), 1 day before ECMO discontinuation or transfer, and 1 day after decannulation. Data were compared with the predicted energy expenditure. Seven patients aged 3 months to 13 years were included. The REE varied greatly both above and below predicted values, from 26 to 154 KCal/kg/day on day 2 of ECMO support. In patients with septic shock, the REE was > 300% above the predicted value on day 2 of ECMO. Before ECMO discontinuation, two of six (33%) children continued to have a REE > 110% of predicted. Three patients had measurements after decannulation, all with a REE < 90% of predicted. REE measurements can be obtained by indirect calorimetry in children receiving ECMO support. ECMO may not provide metabolic rest for all children as a wide variation in REE was observed. For optimal care, individual testing should be considered to match calories provided with the metabolic demand.

[Early predictor of bronchial suture failure after pneumonectomy]

OBJECTIVE

To identify the relationship between serum CRP/albumin and bronchial suture failure after pneumonectomy.

MATERIAL AND METHODS

A retrospective analysis included 100 patients who underwent pneumonectomy with extended lymph node dissection for lung cancer. Patients were divided into 2 groups depending on postoperative complications: group 1 - bronchial stump failure, group 2 - no similar complications. In all patients, we analyzed markers of inflammation (C-reactive protein and albumin) in preoperative period and after 24 postoperative hours. Bronchial stump failure was found in 20 patients (10 patients (14.7%) after left-sided pneumonectomy and 10 (31%) patients after right-sided pneumonectomy). We found a significant relationship between serum CRP/albumin and bronchial stump failure after pneumonectomy (p<0.05). A prognostic formula was based on the ratio of serum C-reactive protein and albumin: PC = CRP/Alb, where PC - prognostic coefficient, CRP - serum C-reactive protein (mg/l) 24 hours after surgery, Alb - serum albumin (g/l) 24 hours after surgery. PC >2.6 determines high risk of bronchial stump failure after pneumonectomy, PC <2.6 - low risk. Sensitivity of this method is 90%, specificity - 97.5%.

External Validation of Equations to Estimate Resting Energy Expenditure in Critically Ill Children and Adolescents with and without Malnutrition: A Cross-Sectional Study

We evaluated the validity of sixteen predictive energy expenditure equations for resting energy expenditure estimation (eREE) against measured resting energy expenditure using indirect calorimetry (REEIC) in 153 critically ill children. Predictive equations were included based on weight, height, sex, and age. The agreement between eREE and REEIC was analyzed using the Bland−Altman method. Precision was defined by the 95% limits of the agreement; differences > ±10% from REEIC were considered clinically unacceptable. The reliability was assessed by the intraclass correlation coefficient (Cronbach’s alpha). The influence of anthropometric, nutritional, and clinical variables on REEIC was also assessed. Thirty (19.6%) of the 153 enrolled patients were malnourished (19.6%), and fifty-four were overweight (10.5%) or obese (24.8%). All patients received sedation and analgesia. Mortality was 3.9%. The calculated eREE either underestimated (median 606, IQR 512; 784 kcal/day) or overestimated (1126.6, 929; 1340 kcal/day) REEIC compared with indirect calorimetry (928.3, 651; 1239 kcal/day). These differences resulted in significant biases of −342 to 592 kcal (95% limits of agreement (precision)−1107 to 1380 kcal/day) and high coefficients of variation (up to 1242%). Although predicted equations exhibited moderate reliability, the clinically acceptable ±10% accuracy rate ranged from only 6.5% to a maximum of 24.2%, with the inaccuracy varying from −31% to +71.5% of the measured patient’s energy needs. REEIC (p = 0.017) and eREE (p < 0.001) were higher in the underweight compared to overweight and obese patients. Apart from a younger age, malnutrition, clinical characteristics, temperature, vasoactive drugs, neuromuscular blockade, and energy intake did not affect REEIC and thereby predictive equations’ accuracy. Commonly used predictive equations for calculating energy needs are inaccurate for individual patients, either underestimating or overestimating REEIC compared with indirect calorimetry. Altogether these findings underscore the urgency for measuring REEIC in clinical situations where accurate knowledge of energy needs is vital.

Vitamin C Deficiency in Critically Ill Children: Prospective Observational Cohort Study

OBJECTIVES

To evaluate the presence of vitamin C deficiency in critically ill children admitted to the PICU.

DESIGN

Single-center prospective observational cohort study.

SETTING

A 28-bed PICU and a pediatric outpatient sedation room of a tertiary-care teaching hospital.

PATIENTS

Two pediatric patient groups 0-21 years old were studied: a PICU group and a group receiving deep sedation for elective outpatient procedures (noncritical care group).

INTERVENTIONS

Vitamin C level was drawn for the PICU group within 24 hours of admission. Vitamin C level was drawn prior to start of deep sedation for the noncritical group.

MEASUREMENT AND MAIN RESULTS

Vitamin C deficiency was present in 11/60 (18%) in the PICU group and 0/21 (0%) of the noncritical group (p < 0.05).

CONCLUSIONS

Vitamin C deficiency was prevalent in our patients admitted to PICU.

Nutritional Management of the Critically Ill Neonate: A Position Paper of the ESPGHAN Committee on Nutrition

OBJECTIVES

The nutritional management of critically ill term neonates and preterm infants varies widely, and controversies exist in regard to when to initiate nutrition, mode of feeding, energy requirements, and composition of enteral and parenteral feeds. Recommendations for nutritional support in critical illness are needed.

METHODS

The ESPGHAN Committee on Nutrition (ESPGHAN-CoN) conducted a systematic literature search on nutritional support in critically ill neonates, including studies on basic metabolism. The Medline database and the Cochrane Library were used in the search for relevant publications. The quality of evidence was reviewed and discussed before voting on recommendations, and a consensus of 90% or more was required for the final approval. Important research gaps were also identified.

RESULTS

This position paper provides clinical recommendations on nutritional support during different phases of critical illness in preterm and term neonates based on available literature and expert opinion.

CONCLUSION

Basic research along with adequately powered trials are urgently needed to resolve key uncertainties on metabolism and nutrient requirements in this heterogeneous patient population.

Hexosylceramides and Glycerophosphatidylcholine GPC(36:1) Increase in Multi-Organ Dysfunction Syndrome Patients with Pediatric Intensive Care Unit Admission over 8-Day Hospitalization

Glycero- and sphingo-lipids are important in plasma membrane structure, caloric storage and signaling. An un-targeted lipidomics approach for a cohort of critically ill pediatric intensive care unit (PICU) patients undergoing multi-organ dysfunction syndrome (MODS) was compared to sedation controls. After IRB approval, patients meeting the criteria for MODS were screened, consented (n = 24), and blood samples were collected from the PICU at HDVCH, Michigan; eight patients needed veno-arterial extracorporeal membrane oxygenation (VA ECMO). Sedation controls were presenting for routine sedation (n = 4). Plasma lipid profiles were determined by nano-electrospray (nESI) direct infusion high resolution/accurate mass spectrometry (MS) and tandem mass spectrometry (MS/MS). Biostatistics analysis was performed using R v 3.6.0. Sixty-one patient samples over three time points revealed a ceramide metabolite, hexosylceramide (Hex-Cer) was high across all time points (mean 1.63-3.19%; vs. controls 0.22%). Fourteen species statistically differentiated from sedation controls (p-value ≤ 0.05); sphingomyelin (SM) [SM(d18:1/23:0), SM(d18:1/22:0), SM(d18:1/23:1), SM(d18:1/21:0), SM(d18:1/24:0)]; and glycerophosphotidylcholine (GPC) [GPC(36:01), GPC(18:00), GPC(O:34:02), GPC(18:02), GPC(38:05), GPC(O:34:03), GPC(16:00), GPC(40:05), GPC(O:36:03)]. Hex-Cer has been shown to be involved in viral infection and may be at play during acute illness. GPC(36:01) was elevated in all MODS patients at all time points and is associated with inflammation and brain injury.

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.

Pediatric Multi-Organ Dysfunction Syndrome: Analysis by an Untargeted "Shotgun" Lipidomic Approach Reveals Low-Abundance Plasma Phospholipids and Dynamic Recovery over 8-Day Period, a Single-Center Observational Study

Lipids are molecules involved in metabolism and inflammation. This study investigates the plasma lipidome for markers of severity and nutritional status in critically ill children. Children with multi-organ dysfunction syndrome (MODS) (n = 24) are analyzed at three time-points and cross-referenced to sedation controls (n = 4) for a total of N = 28. Eight of the patients with MODS, needed veno-arterial extracorporeal membrane oxygenation (VA ECMO) support to survive. Blood plasma lipid profiles are quantified by nano-electrospray (nESI), direct infusion high resolution/accurate mass spectrometry (MS), and tandem mass spectrometry (MS/MS), and compared to nutritional profiles and pediatric logistic organ dysfunction (PELOD) scores. Our results show that PELOD scores were not significantly different between MODS and ECMO cases across time-points (p = 0.66). Lipid profiling provides stratification between sedation controls and all MODS patients for total lysophosphatidylserine (lysoPS) (p-value = 0.004), total phosphatidylserine (PS) (p-value = 0.015), and total ether-linked phosphatidylethanolamine (ether-PE) (p-value = 0.03) after adjusting for sex and age. Nutrition intake over time did not correlate with changes in lipid profiles, as measured by caloric and protein intake. Lipid measurement in the intensive care environment shows dynamic changes over an 8-day pediatric intensive care unit (PICU) course, suggesting novel metabolic indicators for defining critically ill children.

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.

Relationship between inflammation and metabolic regulation of energy expenditure by GLP-1 in critically ill children

BACKGROUND & AIMS

Critical illness is associated with derangement in the metabolic and inflammatory response. Previous investigators have highlighted the cross-link between feeding, inflammation and gut homeostasis. Glucagon like peptide-1 (GLP-1) is a gut derived hormone that plays an important role in the modulation of energy metabolism through appetite regulation and promotion of gastric motility. Growing evidence suggests that GLP-1 might influence energy expenditure. The aim of this study was to assess the relationship between inflammatory activation and metabolic regulation of energy expenditure by assessing cytokine release, levels of GLP-1 and energy expenditure in a cohort of critically ill children.

METHOD

This is a prospective study conducted in critically ill children. A blood sample was collected from each child during the first few days of critical illness, for the analysis of serum inflammatory cytokines (TNF-α, IL-10, IL-6 and IL-1β) and GLP-1 in 42 children. Indirect calorimetry (IC) measurements were performed concurrently in a subset of 21 children. The metabolic index was determined using the ratio of Measured Resting Energy Expenditure (MREE)/Predicted Resting Energy Expenditure (PREE) based on the Schofield equation. Correlation analysis was performed, followed by a stepwise linear regression analysis to assess factors affecting GLP-1 and the metabolic index.

RESULTS

A total of 42 children (0-14 years) were included in this study. The regression analysis indicated that CRP, TNF-α, IL-6 and IL-1β statistically influenced GLP-1 concentrations (p < 0.01). Where IC measurements were performed (N = 21), GLP-1 showed a statistically significant association with the metabolic index (p < 0.01). No evidence of statistical association was recorded between the inflammatory mediators and the metabolic index. Overall the results showed that circulating GLP-1 was increased in response to inflammatory stimuli in critically ill children. GLP-1 contributed to the changes observed in MREE induced by critical illness in our cohort.

CONCLUSION

Energy expenditure is extremely variable in critically ill children, our study suggests that changes in GLP-1 might contribute to a significant amount of this variation. If confirmed in larger studies, GLP-1 could be used as a correction factor for REE predictive equations in critically ill children.

Early Enteral Nutrition Is Associated With Improved Clinical Outcomes in Critically Ill Children: A Secondary Analysis of Nutrition Support in the Heart and Lung Failure-Pediatric Insulin Titration Trial

OBJECTIVES

The impact of early enteral nutrition on clinical outcomes in critically ill children has not been adequately described. We hypothesized that early enteral nutrition is associated with improved clinical outcomes in critically ill children.

DESIGN

Secondary analysis of the Heart and Lung Failure-Pediatric Insulin Titration randomized controlled trial.

SETTING

Thirty-five PICUs.

PATIENTS

Critically ill children with hyperglycemia requiring inotropic support and/or invasive mechanical ventilation who were enrolled for at least 48 hours with complete nutrition data.

INTERVENTIONS

Subjects received nutrition via guidelines that emphasized enteral nutrition and were classified into early enteral nutrition (enteral nutrition within 48 hr of study randomization) and no early enteral nutrition (enteral nutrition after 48 hr of study randomization, or no enteral nutrition at any time).

MEASUREMENTS AND MAIN RESULTS

Of 608 eligible subjects, 331 (54%) received early enteral nutrition. Both early enteral nutrition and no early enteral nutrition groups had similar daily caloric intake over the first 8 study days (median, 36 vs 36 kcal/kg/d; p = 0.93). After controlling for age, body mass index z scores, primary reason for ICU admission, severity of illness, and mean Vasopressor-Inotrope Score at the time of randomization, and adjusting for site, early enteral nutrition was associated with lower 90-day hospital mortality (8% vs 17%; p = 0.007), more ICU-free days (median, 20 vs 17 d; p = 0.02), more hospital-free days (median, 8 vs 0 d; p = 0.003), more ventilator-free days (median, 21 vs 19 d; p = 0.003), and less organ dysfunction (median maximum Pediatric Logistic Organ Dysfunction, 11 vs 12; p < 0.001).

CONCLUSIONS

In critically ill children with hyperglycemia requiring inotropic support and/or mechanical ventilation, early enteral nutrition was independently associated with better clinical outcomes.

Apolipoprotein A-V Is a Novel Diagnostic and Prognostic Predictor in Pediatric Patients with Sepsis: A Prospective Pilot Study in PICU

Background

Sepsis induces the release of lipid mediators, which control both lipid metabolism and inflammation. However, the role of serum apolipoprotein A-V (ApoA5) in sepsis is poorly understood in pediatric patients.

Methods

ApoA5 was screened from serum proteomics profile in lipopolysaccharide- (LPS-) treated mice for 2 h, 24 h, and controls. Then, we conducted a prospective pilot study, and patients with sepsis admitted to a pediatric intensive care unit (PICU) were enrolled from January 2018 to December 2018. Serum ApoA5 levels on PICU admission were determined using enzyme-linked immunosorbent assays (ELISA). Blood samples from 30 healthy children were used as control. The correlation of ApoA5 with the clinical and laboratory parameters was analyzed. Logistic regression analyses and receiver operating characteristic curve (ROC) analysis were used to investigate the potential role of serum ApoA5 as a prognostic predictor for PICU mortality in pediatric patients with sepsis.

Results

A total of 101 patients with sepsis were enrolled in this study. The PICU mortality rate was 10.9% (11/101). Serum ApoA5 levels on PICU admission were significantly lower in nonsurvivors with sepsis compared with survivors (P = 0.009). In subgroup analysis, serum levels of ApoA5 were significantly correlated with sepsis-associated multiple organ dysfunction syndrome (MODS) (P < 0.001), shock (P = 0.002), acute kidney injury (AKI) (P < 0.001), acute liver injury (ALI) (P = 0.002), and gastrointestinal (GI) dysfunction (P = 0.012), but not respiratory failure, brain injury, and pathogenic species (all P > 0.05). Correlation analyses revealed significant correlations of serum ApoA5 with Ca²⁺ concentration. Remarkably, the area under ROC curve (AUC) for serum ApoA5 levels on PICU admission was 0.789 for prediction of PICU mortality with a sensitivity of 75% and a specificity of 84.5% at a threshold value of 822 ng/mL.

Conclusions

Serum ApoA5 level is associated with sepsis-associated shock, AKI, ALI, GI dysfunction, or MODS in children. Moreover, the findings of the present study suggest a prognostic value of ApoA5 in children with sepsis, and lower serum ApoA5 than 822 ng/mL predicts worse outcome in pediatric sepsis.

The Importance of the Microbiome in Critically Ill Patients: Role of Nutrition

Critically ill patients have an alteration in the microbiome in which it becomes a disease-promoting pathobiome. It is characterized by lower bacterial diversity, loss of commensal phyla, like Firmicutes and Bacteroidetes, and a domination of pathogens belonging to the Proteobacteria phylum. Although these alterations are multicausal, many of the treatments administered to these patients, like antibiotics, play a significant role. Critically ill patients also have a hyperpermeable gut barrier and dysregulation of the inflammatory response that favor the development of the pathobiome, translocation of pathogens, and facilitate the emergence of sepsis. In order to restore the homeostasis of the microbiome, several nutritional strategies have been evaluated with the aim to improve the management of critically ill patients. Importantly, enteral nutrition has proven to be more efficient in promoting the homeostasis of the gut microbiome compared to parenteral nutrition. Several nutritional therapies, including prebiotics, probiotics, synbiotics, and fecal microbiota transplantation, are currently being used, showing variable results, possibly due to the unevenness of clinical trial conditions and the fact that the beneficial effects of probiotics are specific to particular species or even strains. Thus, it is of great importance to better understand the mechanisms by which nutrition and supplement therapies can heal the microbiome in critically ill patients in order to finally implement them in clinical practice with optimal safety and efficacy.

Review of oncological emergencies in small animal patients

Oncological emergencies can occur at any time during the course of a malignancy and need to be recognized promptly to maximize successful outcomes. Emergencies are characterized as chemotherapy-induced, paraneoplastic syndromes, or directly related to the neoplasm. Prompt identification with treatment of these emergencies can prolong survival and improve quality of life, even in the setting of terminal illness. This review aims to educate the reader on the pathophysiology, clinical presentation and treatment of some of these emergencies, and to review the current veterinary literature to help educate veterinarians in primary and tertiary facilities to know how to diagnose and treat these serious conditions.

Nutritional Status Deterioration Occurs Frequently During Children's ICU Stay

OBJECTIVES

Malnutrition and faltering growth at PICU admission have been related to suboptimal outcomes. However, little is known about nutritional status deterioration during PICU stay, as critical illness is characterized by a profound and complex metabolism shift, which affects energy requirements and protein turnover. We aim to describe faltering growth occurrence during PICU stay.

DESIGN

Single-center prospective observational study.

SETTING

Twenty-three-bed general PICU, Lyon, France.

PATIENTS

All critically ill children 0-18 years old with length of stay longer than 5 days were included (September 2013-December 2015).

INTERVENTIONS

Weight and height/length were measured at admission, and weight was monitored during PICU stay, in order to calculate body mass index for age z score. Faltering growth was defined as body mass index z score decline over PICU stay. Children admitted during the first year of the study and who presented with faltering growth were followed after PICU discharge for 3 months.

MEASUREMENTS AND MAIN RESULTS

We analyzed 579 admissions. Of them, 10.2% presented a body mass index z score decline greater than 1 SD and 27.8% greater than 0.5. Admission severity risk scores and prolonged PICU stay accounted for 4% of the variability in nutritional status deterioration. Follow-up of post-PICU discharge nutritional status showed recovery within 3 months in most patients.

CONCLUSIONS

Nutritional deterioration is frequent and often intense in critically ill children with length of stay greater than 5 days. Future research should focus on how targeted nutritional therapies can minimize PICU faltering growth and improve post-PICU rehabilitation.

Energy Balance in Critically Ill Children With Severe Sepsis Using Indirect Calorimetry: A Prospective Cohort Study

OBJECTIVES

Energy needs in critically ill children are dynamic and variable. Data on energy balance in children with severe sepsis using indirect calorimetry (IC) is lacking. Thus, we planned to study the energy needs and balance of this cohort.

METHODS

Prospective observational study conducted in ventilated children aged 5 to 12 years, admitted in pediatric intensive care unit with severe sepsis from May 2016 to June 2017. Measured resting energy expenditure (mREE) was measured with IC (Quark RMR, COSMED) till 7 days or pediatric intensive care unit discharge. Predicted energy expenditure (pREE) was estimated using Schofield, Harris and Benedict, and FAO/WHO/UNU equations. Primary outcome was to study the daily energy balance. Secondary outcome was to determine nitrogen balance and agreement of mREE with pREE.

RESULTS

Forty children (24 boys) with median age of 7 (5.2, 10) years were enrolled. All received enteral nutrition; 35 (87.5%) received inotropic support. Median ventilation-free days were 19 days and 4 children died (10%). A total of 176 IC measurements were obtained with an average of 4 per patient. The mean mREE was 51 ± 17 kcal/kg and mean respiratory quotient was 0.77 ± 0.07. There was persistent negative energy balance from days 1 to 7 and negative nitrogen balance from days 1 to 5. There was poor agreement of pREE with mREE using Bland Altman plots. None of severity of illness scores (PRISM III, daily Sequential Organ Function Assessment, daily Vasoactive Inotropic Score) showed correlation with mREE.

CONCLUSIONS

Persistent negative energy and nitrogen balance exist during acute phase of severe sepsis. Predictive equations are inaccurate compared with IC as the criterion standard.

Impact of the route of nutrition on gut mucosa in ventilated adults with shock: an ancillary of the NUTRIREA-2 trial

PURPOSE

The effects of the route of nutrition on the gut mucosa of patients with shock are unclear. Plasma citrulline concentration is a marker of enterocyte mass, and plasma intestinal fatty acid binding protein (I-FABP) concentration is a marker of enterocyte damage. We aimed to study the effect of the route of nutrition on plasma citrulline concentration measured at day 3 of nutrition.

MATERIALS AND METHODS

Ancillary study of the NUTRIREA-2 trial. Ventilated adults with shock were randomly assigned to receive enteral or parenteral nutrition. Enterocyte biomarkers were measured at baseline, day 3, and day 8 of nutrition.

RESULT

A total of 165 patients from 13 French ICUs were included in the study: 85 patients in the enteral group and 80 patients in the parenteral group. At baseline, plasma citrulline was low without difference between groups (12.2 µmol L^-1 vs 13.3 µmol L^-1). At day 3, plasma citrulline concentration was higher in the enteral group than in the parenteral group (18.7 µmol L^-1 vs 15.3 µmol L^-1, p = 0.01). Plasma I-FABP concentration was increased at baseline, without difference between groups (245 pg mL^-1 vs 244 pg mL^-1). Plasma I-FABP concentration was higher in the enteral group than in the parenteral group at day 3 and day 8 (158 pg mL^-1 vs 50 pg mL^-1, p = 0.005 and 225 pg mL^-1 vs 50 pg mL^-1, p = 0.03).

CONCLUSION

Plasma citrulline concentration was higher after 3 days of enteral nutrition than after 3 days of parenteral nutrition. This result raises the question of the possibility that enteral nutrition is associated with a more rapid restoration of enterocyte mass than parenteral nutrition.

Coronary Lesions and Systemic Inflammatory Response Syndrome in Kawasaki Disease

Introduction:

In patients with Kawasaki disease (KD), who later develop coronary artery lesions (CALs), several inflammatory cytokines are reportedly higher than in patients without CALs. Systemic inflammatory response syndrome (SIRS) is used as a clinical index of hypercytokinemia. The objective of this study was to determine whether SIRS is related to CAL formation.

Methods:

We conducted a retrospective cohort study of KD patients admitted to our hospital between July 2012 and July 2015. The subjects were classified into the SIRS or the non-SIRS group based on their vital signs and blood test results. Their initial treatment was determined by their Kobayashi score. We compared the incidence of CALs between the two groups.

Results:

Of 357 KD patients, 277 were included in this study and 175 (63.2%) met the SIRS criteria. The incidence of CAL formation at week 1 in the clinical course and at one month after the primary treatment was significantly higher in the SIRS group than in the non-SIRS group (17.7% vs. 7.8%, p = 0.03 and 10.9% vs. 3.9%, p = 0.03, respectively). Multivariate analyses showed that after adjusting for each variable of the Kobayashi score, SIRS was an independent risk factor for CAL formation at week 1 in the clinical course (odds ratio, 2.7; 95% confidence interval, 1.03–7.23; p = 0.04).

Conclusions:

SIRS can be a risk factor for CAL in the acute phase of KD.

The C-Reactive Protein/Albumin Ratio as a Predictor of Mortality in Critically Ill Patients

The C-reactive protein (CRP)/albumin ratio has recently emerged as a marker for poor prognosis or mortality across various patient groups. This study aimed to identify the association between CRP/albumin ratio and 28-day mortality and predict the accuracy of CRP/albumin ratio for 28-day mortality in medical intensive care unit (ICU) patients. This was a retrospective cohort study of 875 patients. We evaluated the prognostic value of CRP/albumin ratio to predict mortality at 28 days after ICU admission, using Cox proportional hazard model and Kaplan-Meier survival analysis. The 28-day mortality was 28.0%. In the univariate analysis, the Acute Physiology and Chronic Health Evaluation II (APACHE II) score (p < 0.001), CRP level (p = 0.045), albumin level (p < 0.001), and CRP/albumin ratio (p = 0.032) were related to 28-day mortality. The area under the receiver operating characteristic (ROC) curve (the area under the ROC curves (AUC)) of CRP/albumin ratio was higher than that of CRP for mortality (0.594 vs. 0.567, p < 0.001). The cut-off point for CRP/albumin ratio for mortality was 34.3. On Cox proportional-hazard regression analysis, APACHE II score (hazards ratio (HR) = 1.05, 95% confidence interval (CI) = 1.04⁻1.07, p < 0.001) and CRP/albumin ratio (HR = 1.68, 95% CI = 1.27⁻2.21, p < 0.001 for high CRP/albumin ratio) were independent predictors of 28-day mortality. Higher CRP/albumin ratio was associated with increased mortality in critically ill patients.

Overfeeding-associated hyperglycemia and injury-response homeostasis in critically ill neonates

BACKGROUND

Injury severity induces a proportionate acute metabolic stress response, associated with increased risk of hyperglycemia. We hypothesized that excess caloric delivery (overfeeding) during high stress states would increase hyperglycemia and disrupt response homeostasis.

METHODS

Gestational age, daily weight, total daily caloric intake, serum C-reactive protein (CRP), prealbumin, and blood glucose concentrations in all acutely-injured premature NICU infants requiring TPN over the past 3years were reviewed. Injury severity was based on CRP and patients were divided into high (CRP ≥50mg/L) versus low (CRP <50mg/L) stress groups. Glycemic variability was used to measure disruption of homeostasis.

RESULTS

Overall sample included N=563 patient days (37 patients; 42 episodes). High stress group pre-albumin levels negatively correlated with CRP levels (R=-0.62, p<0.005). A test of equal variance demonstrated significantly increased high stress glycemic variability (Ha:ratio>1, Pr(F>f)=0.0353). When high stress patients were separated into high caloric intake (≥70kg/kcal/day) versus low caloric intake (<70kg/kcal/day), maximum serum glucose levels were significantly higher with overfeeding (230.33±55.81 vs. 135.71±37.97mg/dL, p<0.004).

CONCLUSION

Higher injury severity induces increased disruption of response homeostasis in critically ill neonates. TPN-associated overfeeding worsens injury-related hyperglycemia in more severely injured infants.

TYPE OF STUDY

Retrospective study.

LEVEL OF EVIDENCE

Level II.

Multiple Micronutrient Plasma Level Changes Are Related to Oxidative Stress Intensity in Critically Ill Children

OBJECTIVES

Micronutrient supplementation in critically ill adults remains controversial. In the pediatric setting, the impact of oxidative stress on the overall micronutrient status has been poorly explored, due to the limited number of studies and to confounding factors (i.e., malnutrition or extra losses). In order to better understand this phenomenon, we aim to describe micronutrient status, focusing on seven micronutrients, in well-nourished critically ill children presenting with severe oxidative stress.

DESIGN

Prospective, transversal, observational, single-center study.

SETTING

PICU, and anesthesiology department, Lyon, France.

PATIENTS

Three groups of patients were clinically defined: severe oxidative stress PICU group (at least two organ dysfunctions), moderate oxidative stress PICU group (single organ dysfunction), and healthy control group (prior to elective surgery); oxidative stress intensity was controlled by measuring plasma levels of glutathione peroxidase and glutathione. Children presenting any former condition leading to micronutrient deficiency were excluded (malnutrition, external losses).

INTERVENTIONS

Plasma levels of selenium, zinc, copper, vitamin A, vitamin E, vitamin C, and β-carotene were measured in PICU oxidative stress conditions and compared with those of healthy children.

MEASUREMENTS AND MAIN RESULTS

Two hundred one patients were enrolled (51, 48, and 102 in severe, moderate, and healthy control groups, respectively). Median age was 7.1 years (interquartile range, 2.1-13.8 yr). There was a significant trend (p < 0.02) toward plasma level decrease of six micronutrients (selenium, zinc, copper, vitamin E, vitamin C, and β-carotene) while oxidative stress intensity increased. Biological markers of oxidative stress (glutathione peroxidase and glutathione) were in accordance with the clinical definition of the three groups.

CONCLUSIONS

A multiple micronutrient deficiency or redistribution occurs in critically ill children presenting with severe oxidative stress. These findings will help to better identify children who might benefit from micronutrient supplementation and to design adapted supplementation trials in this particular setting.

Can energy intake alter clinical and hospital outcomes in PICU?

BACKGROUND & AIMS

Energy is essential for the treatment and recovery of children admitted to Pediatric Intensive Care Units (PICU). There are significant immediate and long-term health consequences of both under- and over-feeding in this population. Energy requirements of critically ill children vary depending on age, nutritional status, sepsis, fever, pharmacotherapy, and duration and stage of critical illness. This study aimed to determine the incidence of over- and under-feeding and to compare hospital outcomes between these feeding categories. Secondary outcomes were collected to describe the association between feeding categories and biochemistries (serum lactate, triglycerides, C-reactive protein).

METHODS

An ethics approved retrospective study of children admitted to PICU was performed. All intubated patients admitted to PICU (2008-2013) were included, except those in which an IC test was not feasible. Data collection included demographics, the primary outcome variable reported as under feeding (<90%MREE), appropriate (MREE ±10%) or overfeeding (>110% MREE) determined through comparison of measured resting energy expenditure (MREE) using indirect calorimetry (IC) to actual energy intake based on predicted basal metabolic rate (PBMR) and clinical outcomes mechanical ventilation and PICU length of stay (LOS). Data were analysed with descriptive methods, ANOVA and linear regression models.

RESULTS

A total of 139 patients aged 10 (range 0.03-204) months were included. Sixty (43%) were female and 77 (55%) were admitted after a surgical procedure. A total of 210 IC tests were conducted showing a statistically significant difference between MREE measurements and PBMR (p = 0.019). Of the 210 measurements, only 26 measures (12.4%) demonstrated appropriate feeding, while 72 (34.3) were underfed and 112 (53.3%) were overfed. Children who were overfed had significantly longer PICU LOS (median 45.5, IQR 47.8 days) compared to those children in the appropriately fed (median 21.0, IQR 54.5 days), and underfed groups (median 16.5, IQR 21.3 days). There was a mean difference between the over and under feeding category and ventilation days after adjusting for age and PRISM score (p = 0.026), suggesting decreased mechanical ventilation days for underfed. Children who were underfed had significantly higher CRP (median 75.5, IQR 152.8 mg/L) compared to those children in the appropriately fed (median 57.8, IQR 90.9 mg/L) and overfed groups (median 22.4, IQR 56.2 mg/L).

CONCLUSIONS

This retrospective study confirms that estimations of energy expenditure in critically ill children are inaccurate leading to unintended under and overfeeding. Importantly under feeding seems to be associated with fewer mechanical ventilation days and PICU LOS. Further research is required to elucidate the role of optimal nutrition in altering clinical variables in this population.

Longitudinal Profiles of Metabolism and Bioenergetics Associated with Innate Immune Hormonal Inflammatory Responses and Amino-Acid Kinetics in Severe Sepsis and Systemic Inflammatory Response Syndrome in Children

BACKGROUND

Experimental data indicate that sepsis influences the mitochondrial function and metabolism. We aim to investigate longitudinal bioenergetic, metabolic, hormonal, amino-acid, and innate immunity changes in children with sepsis.

METHODS

Sixty-eight children (sepsis, 18; systemic inflammatory response syndrome [SIRS], 23; healthy controls, 27) were enrolled. Plasma amino acids were determined by high-performance liquid chromatography (HPLC); flow-cytometry expressed as mean fluorescence intensity (MFI) of heat shock protein (HSP) levels from monocytes (m) and neutrophils (n); resistin, adiponectin, and extracellular (e) HSPs evaluated by ELISA; ATP levels in white blood cells by luciferase luminescent assay; lipid peroxidation products (TBARS) by colorimetric test; nitrite and nitrate levels by chemiluminescent assay; biliverdin reductase (BVR) activity by enzymatic assay; and energy-expenditure (EE) by E-COVX.

RESULTS

Resistin, eHSP72, eHSP90α, and nitrate were longitudinally higher in sepsis compared with SIRS (p<0.05); mHSP72, nHSP72, VO₂ , VCO₂ , EE, and metabolic pattern were repressed in sepsis compared with SIRS (p<0.05). Septic patients had lower ATP and TBARS compared with controls on day 1, lower ATP compared with SIRS on day 3 (p<0.05), but higher levels of BVR activity. Sepsis exhibited higher phenylalanine levels on day 1, serine on day 3; lower glutamine concentrations on days 3 and 5 (p<0.05). Resistin, inversely related to ATP, was independently associated with sepsis, along with mHSP72 and eHSP90α (p<0.05); TBARS and VO₂ were independently associated with organ failure (p<0.05)). Septic nonsurvivors had malnutrition, persistently repressed metabolism, mHSP72, and induced resistin and adiponectin (p<0.05).

CONCLUSIONS

A pattern of early longitudinal induction of metabolic-hormones and eHSP72/HSP90α, repression of bioenergetics and innate immunity, hypo-metabolism, and amino-acid kinetics changes discriminate sepsis from SIRS; malnutrition, hypo-metabolism, and persistently increased resistin and adiponectin are associated with poor outcome.

Body Composition Changes in Severely Burned Children During ICU Hospitalization

OBJECTIVES

Prolonged hospitalization due to burn injury results in physical inactivity and muscle weakness. However, how these changes are distributed among body parts is unknown. The aim of this study was to evaluate the degree of body composition changes in different anatomical regions during ICU hospitalization.

DESIGN

Retrospective chart review.

SETTING

Children's burn hospital.

PATIENTS

Twenty-four severely burned children admitted to our institution between 2000 and 2015.

INTERVENTIONS

All patients underwent a dual-energy x-ray absorptiometry within 2 weeks after injury and 2 weeks before discharge to determine body composition changes. No subject underwent anabolic intervention. We analyzed changes of bone mineral content, bone mineral density, total fat mass, total mass, and total lean mass of the entire body and specifically analyzed the changes between the upper and lower limbs.

MEASUREMENTS AND MAIN RESULTS

In the 24 patients, age was 10 ± 5 years, total body surface area burned was 59% ± 17%, time between dual-energy x-ray absorptiometries was 34 ± 21 days, and length of stay was 39 ± 24 days. We found a significant (p < 0.001) average loss of 3% of lean mass in the whole body; this loss was significantly greater (p < 0.001) in the upper extremities (17%) than in the lower extremities (7%). We also observed a remodeling of the fat compartments, with a significant whole-body increase in fat mass (p < 0.001) that was greater in the truncal region (p < 0.0001) and in the lower limbs (p < 0.05).

CONCLUSIONS

ICU hospitalization is associated with greater lean mass loss in the upper limbs of burned children. Mobilization programs should include early mobilization of upper limbs to restore upper extremity function.

Similar Metabolic, Innate Immunity, and Adipokine Profiles in Adult and Pediatric Sepsis Versus Systemic Inflammatory Response Syndrome-A Pilot Study

OBJECTIVES

To examine whether the septic profiles of heat shock protein 72, heat shock protein 90α, resistin, adiponectin, oxygen consumption, CO2 production, energy expenditure, and metabolic pattern, along with illness severity, nutritional, and inflammatory indices, differ between adult and pediatric patients compared with systemic inflammatory response syndrome and healthy controls. To evaluate whether these biomolecules may discriminate sepsis from systemic inflammatory response syndrome in adult and pediatric patients.

DESIGN

Prospective cohort study.

SETTING

University ICU and PICU.

PATIENTS

Seventy-eight adults (sepsis/23; systemic inflammatory response syndrome/23; healthy controls/33), 67 children (sepsis/18; systemic inflammatory response syndrome/23; controls/27), mechanically ventilated.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Flow cytometry determined mean fluorescence intensity for monocyte or neutrophil heat shock protein expression. Resistin, adiponectin, and extracellular heat shock proteins were measured using enzyme-linked immunosorbent assay; energy expenditure by E-COVX (GE Healthcare). Genomic DNA was extracted with PureLink Genomic DNA kit (Invitrogen, Carlsbad, CA) to detect heat shock protein 72 single nucleotide polymorphisms. Similarly, in adult and pediatric patients, Acute Physiology and Chronic Evaluation-II/Acute Physiology and Pediatric Risk of Mortality-III, Simplified Acute Physiology Score-III, C-reactive protein, lactate, and resistin were higher and myocardial contractility, monocyte heat shock protein 72, oxygen consumption, CO2 production, energy expenditure, metabolic pattern, glucose, and albumin lower in sepsis compared with systemic inflammatory response syndrome or controls (p < 0.05). For discriminating sepsis from systemic inflammatory response syndrome, resistin, extracellular heat shock protein 90α, and lactate achieved a receiver operating characteristic curve greater than 0.80 in children and greater than 0.75 in adults (p < 0.05). In both, adults and children, genotype heat shock protein 72 analysis did not disclose any diagnosis or mortality group differences regarding either rs6457452 or rs1061581 haplotypes.

CONCLUSIONS

Sepsis presents with similar profiles in adult and pediatric patients, characterized by enhanced inflammatory hormonal response and by repressed innate immunity, metabolism, and myocardial contractility. These features early distinguish sepsis from systemic inflammatory response syndrome across all age groups.

Changes in lipid metabolism in pediatric patients with severe sepsis and septic shock

OBJECTIVES

Limited knowledge exists regarding the lipid profiles of critically ill pediatric patients with systemic inflammatory response syndrome. The aim of this study was to evaluate the relationship between the intensity of the inflammatory response and changes in the lipid profiles of critically ill pediatric patients admitted to a pediatric intensive care unit (PICU) with severe sepsis/septic shock.

METHODS

This was a prospective and observational study at a 15-bed PICU at a public university hospital. We analyzed the lipid profiles of 40 patients with severe sepsis/septic shock admitted to the PICU on the first and seventh days of hospitalization. C-reactive protein was used as a marker for systemic inflammation. Forty-two pediatric patients seen in the emergency department and without systemic inflammatory response syndrome were used to provide control values.

RESULTS

On day 1 of admission to the PICU, the patients had significantly lower levels of total cholesterol (TC), high-density lipoprotein (HDL), and low-density lipoprotein (LDL) as well as higher concentrations of triacylglycerols compared with the control group. There was a significant increase in the TC, HDL, LDL, and apolipoprotein levels from day 1 to day 7 of the study.

CONCLUSIONS

During severe sepsis/septic shock, we found lower serum levels of lipoproteins and apolipoproteins, and these were negatively correlated with C-reactive protein. As the inflammatory response improved, the levels of TC, HDL, LDL, and apolipoproteins increased, suggesting a direct relationship between changes in the lipid profiles and inflammation.

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

The metabolic response to stress and infection is closely related to the corresponding requirements of energy and nutrients. On a general level, the response is driven by a complex endocrine network and related to the nature and severity of the insult. On an individual level, the effects of nutritional interventions are highly variable and a possible source of complications. This narrative review aims to discuss the metabolic changes in critically-ill children and the potential of developing personalized nutritional interventions. Through a literature search strategy, we have investigated the importance of blood glucose levels, the nutritional aspects of the different phases of acute stress response, and the reliability of the available tools to assess the energy expenditure. The dynamics of metabolism during stressful events reveal the difficult balance between risk of hypo- or hyperglycemia and under- or overfeeding. Within this context, individualized and accurate measurement of energy expenditure may help in defining the metabolic needs of patients. Given the variability of the metabolic response in critical conditions, randomized clinical studies in ill children are needed to evaluate the effect of individualized nutritional intervention on health outcomes.

Decreased Microvascular Function in Tanzanian Children With Severe and Uncomplicated Falciparum Malaria

Microvascular function and oxygen consumption affect oxygen homeostasis but have not been assessed in African children with malaria. Microvascular function in Tanzanian children with severe malaria (SM) or uncomplicated malaria were 39% and 72%, respectively, of controls (P < .001). Uncomplicated malaria (P = .04), not SM (P = .06), children had increased oxygen consumption compared with controls.

Protein Requirements of the Critically Ill Pediatric Patient

This article includes a review of protein needs in children during health and illness, as well as a detailed discussion of protein metabolism, including nitrogen balance during critical illness, and assessment and prescription/delivery of protein to critically ill children. The determination of protein requirements in children has been difficult and challenging. The protein needs in healthy children should be based on the amount needed to ensure adequate growth during infancy and childhood. Compared with adults, children require a continuous supply of nutrients to maintain growth. The protein requirement is expressed in average requirements and dietary reference intake, which represents values that cover the needs of 97.5% of the population. Critically ill children have an increased protein turnover due to an increase in whole-body protein synthesis and breakdown with protein degradation leading to loss of lean body mass (LBM) and development of growth failure, malnutrition, and worse clinical outcomes. The results of protein balance studies in critically ill children indicate higher protein needs, with infants and younger children requiring higher intakes per body weight compared with older children. Monitoring the side effects of increased protein intake should be performed. Recent studies found a survival benefit in critically ill children who received a higher percentage of prescribed energy and protein goal by the enteral route. Future randomized studies should evaluate the effect of protein dosing in different age groups on patient outcomes, including LBM, muscle structure and function, duration of mechanical ventilation, intensive care unit and hospital length of stay, and mortality.

Nutrition: A Primary Therapy in Pediatric Acute Respiratory Distress Syndrome

Appropriate nutrition is an essential component of intensive care management of children with acute respiratory distress syndrome (ARDS) and is linked to patient outcomes. One out of every two children in the pediatric intensive care unit (PICU) will develop malnutrition or have worsening of baseline malnutrition and present with specific micronutrient deficiencies. Early and adequate enteral nutrition (EN) is associated with improved 60-day survival after pediatric critical illness, and, yet, despite early EN guidelines, critically ill children receive on average only 55% of goal calories by PICU day 10. Inadequate delivery of EN is due to perceived feeding intolerance, reluctance to enterally feed children with hemodynamic instability, and fluid restriction. Underlying each of these factors is large practice variation between providers and across institutions for initiation, advancement, and maintenance of EN. Strategies to improve early initiation and advancement and to maintain delivery of EN are needed to improve morbidity and mortality from pediatric ARDS. Both, over and underfeeding, prolong duration of mechanical ventilation in children and worsen other organ function such that precise calorie goals are needed. The gut is thought to act as a "motor" of organ dysfunction, and emerging data regarding the role of intestinal barrier functions and the intestinal microbiome on organ dysfunction and outcomes of critical illness present exciting opportunities to improve patient outcomes. Nutrition should be considered a primary rather than supportive therapy for pediatric ARDS. Precise nutritional therapies, which are titrated and targeted to preservation of intestinal barrier function, prevention of intestinal dysbiosis, preservation of lean body mass, and blunting of the systemic inflammatory response, offer great potential for improving outcomes of pediatric ARDS. In this review, we examine the current evidence regarding dose, route, and timing of nutrition, current recommendations for provision of nutrition to children with ARDS, and the current literature for immune-modulating diets for pediatric ARDS. We will examine emerging data regarding the role of the intestinal microbiome in modulating the response to critical illness.

Effects of enteral nutrition with parenteral glutamine supplementation on the immunological function in septic rats

The aim of the present study was to investigate the effects of enteral nutrition (EN) with parenteral glutamine (GLN) supplementation on inflammatory response, lymphatic organ apoptosis, immunological function and survival in septic rats by caecal ligation and puncture (CLP). Male rats were randomly assigned into two experimental groups and two sham CLP control groups (n 10 per group). After CLP or sham CLP model and nutrition programme were completed, the GLN concentrations of plasma and tissues and several indices of immunological function including serum Ig content, circulating lymphocyte number, the CD4:CD8 ratio, the neutrophil phagocytosis index (NPI), the organ index and apoptosis of thymus and spleen, and plasma cytokine levels were determined. Moreover, the survival in septic rats was observed. The results revealed that EN with parenteral GLN supplementation remarkably increased the GLN concentrations of plasma and tissues, serum Ig content, the circulating lymphocyte number, the CD4:CD8 ratio, the indexes of thymus and spleen, NPI and survival compared with the control group (P< 0·05). In contrast, the apoptosis of thymus and spleen and the levels of TNF-α, IL-1β and IL-6 in plasma were obviously decreased compared with the control group (P< 0·05). These results show that EN with parenteral GLN supplementation diminished the release of inflammatory cytokines, attenuated lymphatic organ apoptosis, enhanced the immunological function and improved survival in septic rats.

Systemic inflammation increases energy expenditure following pediatric cardiopulmonary bypass

OBJECTIVES

To examine the association between cardiopulmonary bypass-related systemic inflammation and resting energy expenditure in pediatric subjects following cardiac surgery.

DESIGN

Single-center, prospective cohort study.

SETTING

Pediatric cardiac critical care unit in Toronto, Canada.

PATIENTS

Children with congenital heart disease undergoing cardiopulmonary bypass surgery.

INTERVENTIONS

Resting energy expenditure was determined by indirect calorimetry and the modified Weir equation, using VO2 and VCO2 measured by in-line respiratory mass spectrometry. Measurements were taken at baseline and 6-hour intervals from separation from cardiopulmonary bypass for a maximum of 72 hours. Plasma interleukin-6, glucose delivery, feeding status, and cardiac output (calculated by Fick equation) were monitored at each resting energy expenditure measurement.

MEASUREMENTS AND MAIN RESULTS

We studied 111 subjects at a median (interquartile range) age of 5.3 months (0.8-10.5 mo), weighing 5.7 kg (3.9-8.1 kg), of whom 88% underwent biventricular repair. Resting energy expenditure decreased from 51 kcal/kg/d to 45 kcal/kg/d during the study period. Resting energy expenditure was positively associated with increased plasma interleukin-6 (estimate variable, 1.76; p = 0.001) and inversely associated with preoperative methylprednisolone use (estimate variable, -6.7; p = 0.003) even after accounting for other predictors. Increase in cardiac output was also associated (estimate variable, 13.7; p < 0.0001) with higher resting energy expenditure.

CONCLUSIONS

Resting energy expenditure ranges between 40 and 60 kcal/kg/d and decreases progressively in children following cardiopulmonary bypass surgery. It is directly associated with increased inflammation and higher cardiac output and inversely associated with anti-inflammatory strategies. Further studies are required to predict the appropriate caloric delivery in this cohort.

Parenteral glutamine supplementation in combination with enteral nutrition improves intestinal immunity in septic rats

OBJECTIVES

The gut-associated lymphoid tissue is continuously exposed to antigens in the gut lumen and becomes the first line of defense against enteric bacteria and associated toxin. The aim of this study was to investigate the effects of parenteral glutamine (GLN) supplementation in combination with enteral nutrition (EN) on intestinal mucosal immunity in septic rats by cecal ligation and puncture (CLP).

METHODS

Male Sprague-Dawley rats were randomly assigned into four groups: A sham CLP + EN + saline group (n = 10), a sham CLP + EN + GLN group (n = 10), a CLP + EN + saline group (n = 10), and a CLP + EN + GLN group (n = 10). At 2 h after CLP or sham CLP, all rats in each of the four groups received an identical enteral nutrition solution as their base formula. Then, the rats in the sham CLP + EN + GLN group and CLP + EN + GLN group were given 0.35 g GLN/kg body weight daily for 7 d, all at the same time, via a tail vein injection; whereas those in the sham CLP + EN + saline group and CLP + EN + saline group were daily administered isovolumic sterile 0.9% saline for comparison. All rats in each of the four groups were given 290 kcal/kg body wt/d for 7 d. At the end of the seventh day after the nutritional program was finished, all rats were euthanized and the entire intestine was collected. Total Peyer's patches (PP) cell yield was counted by a hemocytometer. The percentage of PP lymphocyte subsets was analyzed by flow cytometry. The number of intestinal lamina propria IgA plasma cells was determined by the immunohistochemistry technique. The intestinal immunoglobulin A (IgA) levels were assessed by ELISA. PP apoptosis was evaluated by terminal deoxyuridine nick-end labeling.

RESULTS

The results revealed total PP cell yield, the numbers of PP lymphocyte subsets, intestinal lamina propria IgA plasma cells, and intestinal IgA levels in the CLP + EN + GLN group were significantly increased when compared with the CLP + EN + saline group (P < 0.05). On the other hand, the number of TUNEL-stained cells within PPs in the CLP + EN + GLN group was markedly decreased as compared with the CLP + EN + saline group (P < 0.05).

CONCLUSION

The results of this study show that parenteral glutamine supplementation in combination with enteral nutrition may attenuate PP apoptosis, increase PP cell yield and intestinal lamina propria IgA plasma cells, and subsequently improve intestinal mucosal immunity. Clinically, these results suggest therapeutic efforts at improving intestinal immunity may contribute to the prevention and treatment of sepsis.

Accuracy of a simplified equation for energy expenditure based on bedside volumetric carbon dioxide elimination measurement--a two-center study

BACKGROUND & AIMS

Accurate assessment of resting energy expenditure (REE) and metabolic state is essential to optimize nutrient intake in critically ill patients. We aimed to examine the accuracy of a simplified equation for predicting REE using carbon dioxide elimination (VCO2) values.

METHODS

We conducted a two-center study of metabolic data from mechanically ventilated children less than 18 years of age. Mean respiratory quotient (RQ) from the derivation set (n = 72 subjects) was used to modify the Weir equation to obtain a simplified equation based on VCO2 measurements alone. This equation was then applied to subjects at the second institution (validation dataset, n = 94) to predict resting energy expenditure. Bland-Altman analysis was used to assess the agreement between measured REE values, and REE estimated by the new equation as well as the Schofield equation. We also examined the accuracy of the new equation in classifying patients according to their metabolic state.

RESULTS

Mean respiratory quotient (± SD) of 0.89 ± 0.09 in the derivation set was used to obtain a simplified equation, REE (kcal/day) = 5.534*VCO2 (L/min)*1440. In relation to the measured REE in the validation set, the mean bias (limits of agreement) for the REE predicted by this equation was -0.65% (-14.4-13.1%); and the overall diagnostic accuracy for classifying subjects as hypometabolic or hypermetabolic was 84%. Mean bias (limits) of agreement between measured and Schofield equation estimated REE was -0.1% (-40.5-40.7%).

CONCLUSIONS

A simplified metabolic equation using VCO2 values was superior to the standard equation in estimating REE, and provided a reasonably accurate metabolic classification in mechanically ventilated children. In the absence of indirect calorimetry, bedside VCO2 monitoring could provide valuable continuous metabolic information to guide optimal nutrient intake.

Nutrition Monitoring in the PICU

The ideal set of variables for nutritional monitoring that may correlate with patient outcomes has not been identified. This is particularly difficult in the PICU patient because many of the standard modes of nutritional monitoring, although well described and available, are fraught with difficulties. Thus, repeated anthropometric and laboratory markers must be jointly analyzed but individually interpreted according to disease and metabolic changes, in order to modify and monitor the nutritional treatment. In addition, isotope techniques are neither clinically feasible nor compatible with the multiple measurements needed to follow progression. On the other hand, indirect alternatives exist but may have pitfalls, of which the clinician must be aware. Risks exist for both overfeeding and underfeeding of PICU patients so that an accurate monitoring of energy expenditure, using targeted indirect calorimetry, is necessary to avoid either extreme. This is very important, since the monitoring of the nutritional status of the critically ill child serves as a guide to early and effective nutritional intervention.

CD64-Neutrophil expression and stress metabolic patterns in early sepsis and severe traumatic brain injury in children

Background

Critical illness constitutes a serious derangement of metabolism. The aim of our study was to compare acute phase metabolic patterns in children with sepsis (S) or severe sepsis/septic shock (SS) to those with severe traumatic brain injury (TBI) and healthy controls (C) and to evaluate their relations to neutrophil, lymphocyte and monocyte expressions of CD64 and CD11b.

Methods

Sixty children were enrolled in the study. Forty-five children with systemic inflammatory response syndrome (SIRS) were classified into three groups: TBI (n = 15), S (n = 15), and SS (n = 15). C consisted of 15 non- SIRS patients undergoing screening tests for minor elective surgery. Blood samples were collected within 6 hours after admission for flow cytometry of neutrophil, lymphocyte and monocyte expression of CD64 and CD11b (n = 60). Procalcitonin (PCT), C-reactive protein (CRP), glucose, triglycerides (TG), total cholesterol (TC), high (HDL) or low-density-lipoproteins (LDL) were also determined in all groups, and repeated on day 2 and 3 in the 3 SIRS groups (n = 150).

Results

CRP, PCT and TG (p < 0.01) were significantly increased in S and SS compared to TBI and C; glucose did not differ among critically ill groups. Significantly lower were the levels of TC, LDL, and HDL in septic groups compared to C and to moderate changes in TBI (p < 0.0001) but only LDL differed between S and SS (p < 0.02). Among septic patients, PCT levels declined significantly (p < 0.02) with time, followed by parallel decrease of HDL (p < 0.03) and increase of TG (p < 0.02) in the SS group. Neutrophil CD64 (nCD64) expression was higher in patients with SS (81.2%) and S (78.8%) as compared to those with TBI (5.5%) or C (0.9%, p < 0.0001). nCD64 was positively related with CRP, PCT, glucose, and TG (p < 0.01) and negatively with TC, LDL, and HDL (p < 0.0001), but not with severity of illness, hematologic indices, length of stay or mechanical ventilation duration.

Conclusions

In sepsis, the early stress-metabolic pattern is characterized by a high (nCD64, glucose, TG) - low (TC, HDL, LDL) combination in contrast to the moderate pattern of TBI in which only glucose increases combined with a moderate cholesterol - lipoprotein decrease. These early metabolic patterns persist the first 3 days of acute illness and are associated with the acute phase CD64 expression on neutrophils.

Systematic review of the influence of energy and protein intake on protein balance in critically ill children

OBJECTIVE

To examine the influence of protein and energy intakes on protein balance in children receiving mechanical ventilation in the pediatric intensive care unit.

STUDY DESIGN

We hypothesized that higher energy and protein intakes are correlated with positive protein balance. We performed a systematic literature search to identify studies reporting protein balance in children requiring mechanical ventilation. Factors contributing to protein balance, including protein and energy intake, age, illness severity, study design, and feeding routes, were analyzed using a qualitative approach.

RESULTS

Nine studies met the entry criteria and were included in the final analysis. Positive nitrogen balance was reported in 6 of the studies, with a wide range of associated energy and protein intakes. Measures of central tendency for daily energy and protein intakes were significantly correlated with positive protein balance. A minimum intake of 57 kcal/kg/day and 1.5 g protein/kg/day were required to achieve positive protein balance.

CONCLUSION

We found a correlation between higher energy and protein intakes and achievement of positive protein balance in children receiving mechanical ventilation in the pediatric intensive care unit. However, there is a paucity of interventional studies, and a variety of protocols have been used to determine nitrogen balance. Larger clinical trials with uniform methodology are needed to further examine the effect of energy and protein intake on protein balance, lean body mass, and clinical outcomes in children on mechanical ventilation.

The immunopathology of sepsis: pathogen recognition, systemic inflammation, the compensatory anti-inflammatory response, and regulatory T cells

Sepsis, the systemic inflammatory response to infection, represents the major cause of death in critically ill veterinary patients. Whereas important advances in our understanding of the pathophysiology of this syndrome have been made, much remains to be elucidated. There is general agreement on the key interaction between pathogen-associated molecular patterns and cells of the innate immune system, and the amplification of the host response generated by pro-inflammatory cytokines. More recently, the concept of immunoparalysis in sepsis has also been advanced, together with an increasing recognition of the interplay between regulatory T cells and the innate immune response. However, the heterogeneous nature of this syndrome and the difficulty of modeling it in vitro or in vivo has both frustrated the advancement of new therapies and emphasized the continuing importance of patient-based clinical research in this area of human and veterinary medicine.