Continuous renal replacement therapy amino acid, trace metal and folate clearance in critically ill children

Clinical practice guidelines for nutritional assessment and monitoring of adult ICU patients in China

The Chinese Society of Critical Care Medicine (CSCCM) has developed clinical practice guidelines for nutrition assessment and monitoring for patients in adult intensive care units (ICUs) in China. This guideline focuses on nutrition evaluation and metabolic monitoring to achieve optimal and personalized nutrition therapy for critically ill patients. This guideline was developed by experts in critical care medicine and evidence-based medicine methodology and was developed after a thorough review of the system and a summary of relevant trials or studies published from 2000 to July 2023. A total of 18 recommendations were formed and consensus was reached through discussions and reviews by expert groups in critical care medicine, parenteral and enteral nutrition, and surgery. The recommendations are based on currently available evidence and cover several key fields, including screening and assessment, evaluation and assessment of enteral feeding intolerance, metabolic and nutritional measurement and monitoring during nutrition therapy, and organ function evaluation related to nutrition supply. Each question was analyzed according to the Population, Intervention, Comparison, and Outcome (PICO) principle. In addition, interpretations were provided for four questions that did not reach a consensus but may have potential clinical and research value. The plan is to update this nutrition assessment and monitoring guideline using the international guideline update method within 3-5 years.

Nutrition in critically ill children with acute kidney injury on continuous kidney replacement therapy: a 2023 executive summary

OBJECTIVES

Nutrition plays a vital role in the outcome of critical illness in children, particularly those with acute kidney injury. Currently, there are no established guidelines for children with acute kidney injury treated with continuous kidney replacement therapy. Our objective was to create clinical practice points for nutritional assessment and management in critically ill children with acute kidney injury receiving continuous kidney replacement therapy.

METHODS

An electronic search using PubMed and an inclusive academic library search (including MEDLINE, Cochrane, and Embase databases) was conducted to find relevant English-language articles on nutrition therapy for children (<18 y of age) receiving continuous kidney replacement therapy.

RESULTS

The existing literature was reviewed by our work group, comprising pediatric nephrologists and experts in nutrition. The modified Delphi method was then used to develop a total of 45 clinical practice points. The best methods for nutritional assessment are discussed. Indirect calorimetry is the most reliable method of predicting resting energy expenditure in children on continuous kidney replacement therapy. Schofield equations can be used when indirect calorimetry is not available. The non-intentional calories contributed by continuous kidney replacement therapy should also be accounted for during caloric dosing. Protein supplementation should be increased to account for the proteins, peptides, and amino acids lost with continuous kidney replacement therapy.

CONCLUSIONS

Clinical practice points are provided on nutrition assessment, determining energy needs, and nutrient intake in children with acute kidney injury and on continuous kidney replacement therapy based on the existing literature and expert opinions of a multidisciplinary panel.

Advances in pediatric acute kidney injury pharmacology and nutrition: a report from the 26th Acute Disease Quality Initiative (ADQI) consensus conference

BACKGROUND

In the past decade, there have been substantial advances in our understanding of pediatric AKI. Despite this progress, large gaps remain in our understanding of pharmacology and nutritional therapy in pediatric AKI.

METHODS

During the 26th Acute Disease Quality Initiative (ADQI) Consensus Conference, a multidisciplinary group of experts reviewed the evidence and used a modified Delphi process to achieve consensus on recommendations for gaps and advances in care for pharmacologic and nutritional management of pediatric AKI. The current evidence as well as gaps and opportunities were discussed, and recommendations were summarized.

RESULTS

Two consensus statements were developed. (1) High-value, kidney-eliminated medications should be selected for a detailed characterization of their pharmacokinetics, pharmacodynamics, and pharmaco-"omics" in sick children across the developmental continuum. This will allow for the optimization of real-time modeling with the goal of improving patient care. Nephrotoxin stewardship will be identified as an organizational priority and supported with necessary resources and infrastructure. (2) Patient-centered outcomes (functional status, quality of life, and optimal growth and development) must drive targeted nutritional interventions to optimize short- and long-term nutrition. Measures of acute and chronic changes of anthropometrics, body composition, physical function, and metabolic control should be incorporated into nutritional assessments.

CONCLUSIONS

Neonates and children have unique metabolic and growth parameters compared to adult patients. Strategic investments in multidisciplinary translational research efforts are required to fill the knowledge gaps in nutritional requirements and pharmacological best practices for children with or at risk for AKI.

Nutrition in Critically Ill Children with AKI on Continuous RRT: Consensus Recommendations

BACKGROUND

Nutrition plays a vital role in the outcome of critically ill children, particularly those with AKI. Currently, there are no established guidelines for children with AKI treated with continuous RRT (CRRT). A thorough understanding of the metabolic changes and nutritional challenges in AKI and CRRT is required. Our objective was to create clinical practice points for nutritional assessment and management in critically ill children with AKI receiving CRRT.

METHODS

PubMed, MEDLINE, Cochrane, and Embase databases were searched for articles related to the topic. Expertise of the authors and a consensus of the workgroup were additional sources of data in the article. Available articles on nutrition therapy in pediatric patients receiving CRRT through January 2023.

RESULTS

On the basis of the literature review, the current evidence base was examined by a panel of experts in pediatric nephrology and nutrition. The panel used the literature review as well as their expertise to formulate clinical practice points. The modified Delphi method was used to identify and refine clinical practice points.

CONCLUSIONS

Forty-four clinical practice points are provided on nutrition assessment, determining energy needs, and nutrient intake in children with AKI and on CRRT on the basis of the existing literature and expert opinions of a multidisciplinary panel.

Challenges of Nutrition Support in Pediatric Patients Requiring Extracorporeal Membrane Oxygenation

Nutrition support in critically ill infants and children remains an integral part of providing optimal care for these patients. The pediatric patient requiring extracorporeal membrane oxygenation therapy faces specific challenges to the provision of suitable nutrition support. In this review, we aimed to summarize the existing literature around some of the more challenging aspects of delivering appropriate nutrition to children receiving extracorporeal membrane oxygenation.

Optimizing Nutrition in Neonates with Kidney Dysfunction

The nutritional management of neonates with kidney disease is complex. There may be significant differences in nutritional needs based on the duration and cause of kidney dysfunction, including acute kidney injury (AKI) and chronic kidney disease (CKD). Furthermore, the treatment modality, including acute (continuous renal replacement therapy and peritoneal dialysis [PD]) and chronic (intermittent hemodialysis and PD) approaches may differentially affect nutritional losses and dietary needs. In this review, we discuss the pathophysiology of compromised nutrition in neonates with AKI and CKD. We also summarize the existing data and consensus recommendations on the provision of nutrition to neonates with AKI and CKD. We highlight the paucity of data on micronutrient losses and the need for future prospective studies to enhance nutritional supplementation to hopefully improve outcomes in these patients.

Nutritional management of children with acute kidney injury-clinical practice recommendations from the Pediatric Renal Nutrition Taskforce

The nutritional management of children with acute kidney injury (AKI) is complex. The dynamic nature of AKI necessitates frequent nutritional assessments and adjustments in management. Dietitians providing medical nutrition therapies to this patient population must consider the interaction of medical treatments and AKI status to effectively support both the nutrition status of patients with AKI as well as limit adverse metabolic derangements associated with inappropriately prescribed nutrition support. The Pediatric Renal Nutrition Taskforce (PRNT), an international team of pediatric renal dietitians and pediatric nephrologists, has developed clinical practice recommendations (CPR) for the nutritional management of children with AKI. We address the need for intensive collaboration between dietitians and physicians so that nutritional management is optimized in line with AKI medical treatments. We focus on key challenges faced by dietitians regarding nutrition assessment. Furthermore, we address how nutrition support should be provided to children with AKI while taking into account the effect of various medical treatment modalities of AKI on nutritional needs. Given the poor quality of evidence available, a Delphi survey was conducted to seek consensus from international experts. Statements with a low grade or those that are opinion-based must be carefully considered and adapted to individual patient needs, based on the clinical judgment of the treating physician and dietitian. Research recommendations are provided. CPRs will be regularly audited and updated by the PRNT.

An Overview of Type B Lactic Acidosis Due to Thiamine (B1) Deficiency

Type B lactic acidosis can occur secondary to several factors, including thiamine deficiency, and is not as common as type A. Recognizing thiamine deficiency-associated lactic acidosis is challenging because serum thiamine concentrations are not routinely obtained, and a thorough and specific history is necessary for clinicians to suspect thiamine deficiency as a root cause. Furthermore, the appropriate dose and duration of thiamine treatment are not well defined. Untreated thiamine deficiency-associated lactic acidosis can lead to critical illness requiring lifesaving extracorporeal therapies. Additionally, if thiamine and glucose are not administered in an appropriate sequence, Wernicke encephalopathy or Korsakoff syndrome may occur. This review aims to summarize therapeutic treatment for thiamine deficiency-associated lactic acidosis, based on case reports/series and nutritional guidance. After a literature search of the PubMed database, 63 citations met inclusion criteria, of which 21 involved pediatric patients and are the focus of this review. -Citations describe dosing regimens ranging from 25 to 1000 mg of intravenous (IV) thiamine as a single dose, or multiple daily doses for several days. Specific guidance for critically ill adults recommends a thiamine range of 100 mg IV once daily to 400 mg IV twice daily. Although there are no specific recommendations for the pediatric population, given the relative safety of thiamine administration, its low cost, and our review of the literature, treatment with thiamine 100 to 200 mg IV at least once is supported, with ongoing daily doses based on clinical response of the patient, regardless of age.

Nutrition for critically ill children and neonates requiring dialysis: Application of clinical practice recommendations

Approximately 30% of all children and neonates admitted to the intensive care unit (ICU) experience acute kidney injury (AKI). Children with AKI are largely poorly fed and experience high rates of malnutrition. Nutrition prescription and provision are exceptionally challenging for critically ill neonates, infants, and children with AKI given the dynamic nature of AKI and its respective treatment modalities. Managing the nutrition prescription of critically ill neonates, infants, and children with AKI requires nutrition support clinicians to have a high-level understanding of the various treatment modalities for AKI, which can affect the patient's protein, fluid, electrolyte, and mineral needs. Accurate and timely nutrition assessment in critically ill neonates and children with AKI can be flawed owing to difficulty obtaining accurate anthropometric parameters. Recently, the Pediatric Renal Nutrition Taskforce introduced clinical practice recommendations for the nutrition management of children with AKI. In this review, we will discuss the practical implications of these recent guidelines and work to bridge the knowledge and practice gaps for pediatric and neonatal nutrition support clinicians providing nutrition therapy for patients with AKI in the ICU. We also appraise special nutrition-related considerations for neonates with AKI given newer available renal replacement treatment modalities.

Metabolic and nutritional aspects in continuous renal replacement therapy

Nutrition is one of the foundations for supporting and treating critically ill patients. Nutritional support provides calories, protein, electrolytes, vitamins, and trace elements via the enteral or parenteral route. Acute kidney injury (AKI) is a common and devastating problem in critically ill patients and has significant metabolic and nutritional consequences. Moreover, renal replacement therapy (RRT), whatever the modality used, also profoundly impacts metabolism. RRT and of the extracorporeal circuit impede 'effect the evaluation of a patient's energy requirements by clinicians. Substrates added and removed within the extracorporeal treatment are not always taken into consideration, making treatment even more challenging. Furthermore, evidence on nutritional support during continuous renal replacement therapy (CRRT) is scarce, and there are no clinical guidelines for nutrition adaptations during CRRT in critically ill patients. Most recommendations are based on expert opinions. This review discusses the complex interaction between nutritional support and CRRT and presents some milestones for nutritional support in critically ill patients on CRRT.

The effect of continuous venovenous hemodiafiltration on amino acid delivery, clearance, and removal in children

BACKGROUND

In critically ill children with acute kidney injury (AKI), continuous kidney replacement therapy (CKRT) enables nutrition provision. The magnitude of amino acid loss during continuous venovenous hemodiafiltration (CVVHDF) is unknown and needs accurate quantification. We investigated the mass removal and clearance of amino acids in pediatric CVVHDF.

METHODS

This is a prospective observational cohort study of patients receiving CVVHDF from August 2014 to January 2016 in the pediatric intensive care unit (PICU) of a tertiary children's hospital.

RESULTS

Fifteen patients (40% male, median age 2.0 (IQR 0.7, 8.0) years) were enrolled. Median PICU and hospital lengths of stay were 20 (9, 59) and 36 (22, 132) days, respectively. Overall survival to discharge was 66.7%. Median daily protein prescription was 2.00 (1.25, 2.80) g/kg/day. Median daily amino acid mass removal was 299.0 (174.9, 452.0) mg/kg body weight, and median daily amino acid mass clearance was 18.2 (13.5, 27.9) ml/min/m², resulting in a median 14.6 (8.3, 26.7) % protein loss. The rate of amino acid loss increased with increasing dialysis dose and blood flow rate.

CONCLUSION

CVVHDF prescription and related amino acid loss impact nutrition provision, with 14.6% of the prescribed protein removed. Current recommendations for protein provision for children requiring CVVHDF should be adjusted to compensate for circuit-related loss. A higher resolution version of the Graphical abstract is available as Supplementary information.

Fluid Restriction Contributes to Poor Nutritional Adequacy in Patients With Congenital Heart Disease Receiving Renal Replacement Therapy

OBJECTIVES

Critically ill patients receiving renal replacement therapy (RRT) in the pediatric cardiac intensive care unit (CICU) are at high risk for inadequate nutrition delivery. The objective of this study is to evaluate barriers to adequate energy and protein delivery in critically ill patients with congenital heart disease receiving RRT.

METHODS

This is a single-center retrospective cohort study of patients receiving RRT in the CICU from 2011 to 2019. Energy and protein adequacy was recorded over the first 7 days of RRT. Adequacy was defined as delivery of >80% of the energy and protein targets during this time period. Patients who achieved adequacy were compared to those who did not. Multivariable logistic regression models were constructed to determine factors independently associated with energy and protein adequacy while receiving RRT.

RESULTS

Sixty patients were included for analysis. Fifty-five patients (92%) achieved energy adequacy and 37 patients (62%) achieved protein adequacy. A higher weight-for-age z-score (WAZ) on admission to the CICU was the only independent predictor of inadequate energy intake (odds ratio 0.07, 95% confidence interval 0.01-0.58, P = .014); median WAZ was -1.17 versus +1.24 for those with adequate versus inadequate energy intake, respectively. Fluid restriction to <80% of maintenance fluid at the time of RRT initiation was more likely in patients with higher WAZ. Fluid restriction was the only independent predictor of inadequate protein intake (odds ratio 0.13, 95% confidence interval 0.02-0.7, P = .018); 5% versus 30% were fluid restricted in those with adequate versus inadequate protein intake, respectively. Azotemia was not associated with inadequate protein intake. Initiation of RRT did not allow for liberalization of fluid intake over the time period evaluated.

CONCLUSIONS

Protein delivery was inadequate in 38% of children undergoing RRT in the CICU. Fluid restriction was associated with inadequate protein intake and higher WAZ was associated with inadequate energy intake.

Nutrition in Pediatric Extracorporeal Membrane Oxygenation: A Narrative Review

Extracorporeal membrane oxygenation (ECMO) support is increasingly utilized in quaternary pediatric intensive care units. Metabolic derangements and altered nutritional requirements are common in critically ill children supported on ECMO. However, there remains no consensus on the optimal approach to the prescription of nutrition in these patients. This narrative review aims to summarize the current medical literature on various aspects of nutrition support in pediatric patients on ECMO. These include: (1) nutritional adequacy, (2) pros and cons of feeding on ECMO, (3) enteral vs. parenteral nutrition, and (4) proposed recommendations and future directions for research in this area.

Nutrition Considerations in Neonatal Extracorporeal Life Support

Extracorporeal life support (ECLS) is a life-saving therapy, but neonates who require ECLS have unique nutritional needs and require aggressive, early nutritional support. These critically ill neonates are at increased risk for long-term feeding difficulties, malnutrition, and growth failure with associated increased morbidity and mortality. Unfortunately, few studies specific to this population exist. Clinical guidelines published by the American Society for Parenteral and Enteral Nutrition are specific to this population and available to aid clinicians in appropriate nutrition regimens, but studies to date suggest that nutrition provision varies greatly from center to center and often is inadequate. Though enteral feedings are becoming more common, aggressive parenteral nutrition is still needed to ensure nutrition goals are met, including the goal of increased protein provision. Long-term complications, including the need for tube feedings and growth failure, are common in neonatal ECLS survivors, particularly those with congenital diaphragmatic hernia. Oral aversion with poor feeding and growth failure must be anticipated and recognized early if present. The nutritional implications associated with the development of acute kidney injury, fluid overload, or the use of continuous renal replacement therapy must be recognized. In this state-of-the-art review, we examine aspects of nutrition for neonates receiving ECLS including nutritional requirements, nutrition provision, current practices, long-term outcomes, and special population considerations.

ESPEN guideline on clinical nutrition in hospitalized patients with acute or chronic kidney disease

Acute kidney disease (AKD) - which includes acute kidney injury (AKI) - and chronic kidney disease (CKD) are highly prevalent among hospitalized patients, including those in nephrology and medicine wards, surgical wards, and intensive care units (ICU), and they have important metabolic and nutritional consequences. Moreover, in case kidney replacement therapy (KRT) is started, whatever is the modality used, the possible impact on nutritional profiles, substrate balance, and nutritional treatment processes cannot be neglected. The present guideline is aimed at providing evidence-based recommendations for clinical nutrition in hospitalized patients with AKD and CKD. Due to the significant heterogeneity of this patient population as well as the paucity of high-quality evidence data, the present guideline is to be intended as a basic framework of both evidence and - in most cases - expert opinions, aggregated in a structured consensus process, in order to update the two previous ESPEN Guidelines on Enteral (2006) and Parenteral (2009) Nutrition in Adult Renal Failure. Nutritional care for patients with stable CKD (i.e., controlled protein content diets/low protein diets with or without amino acid/ketoanalogue integration in outpatients up to CKD stages four and five), nutrition in kidney transplantation, and pediatric kidney disease will not be addressed in the present guideline.

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.

[Nutrition in children with continuous renal replacement therapy]

INTRODUCTION

The aim of this study was to analyse the nutritional state, diet and gastrointestinal complications of children that require continuous renal replacement therapy (CRRT).

MATERIAL AND METHODS

A retrospective analysis of a database, which included the information about patients who required CRRT between the years 2013 and 2017. Data were collected on the replacement technique, type of nutrition, calorie and protein intake, gastrointestinal complications, and clinical course.

RESULTS

A total of 65 children (61.5% male) were treated with CRRT, and 24 patients (37%) also needed ECMO support. Just over one-quarter (27.7%) of patients had a weight less than P3, and 48.4% of them a height less than P3. At the beginning of the technique, 31 children (47.7%) received enteral nutrition, at the end, there were 52 patients receiving enteral nutrition (80%). The transpyloric tube was used to provide nutrition in 76% of the cases. The median caloric intake was 63kcal/kg/day, and the protein intake was 1.6g/kg/day. There were gastrointestinal difficulties during the process in 48 patients (73.8%), with 29 (44.6%) patients being diagnosed with gastric distension or excessive gastric remains, 22 (33.8%) with constipation, 8 (12.3%) with vomiting, and 4 (6.1%) diarrhoea. One patient treated with ECMO presented with intestinal ischaemia. Enteral nutrition was cancelled in 3 patients (4.6%) due to the complications. There was no relationship between complications and type of diet or ECMO assistance.

CONCLUSIONS

A high percentage of children treated with CRRT showed undernutrition but they had adequate tolerance to the enteral nutrition. Although the gastrointestinal complications percentage was high in few subjects, these complications are the reason why enteral nutrition was stopped.

Feeding modality is a barrier to adequate protein provision in children receiving continuous renal replacement therapy (CRRT)

BACKGROUND

Critically ill children have a high prevalence of malnutrition. Children with acute kidney injury experience high rates of protein debt. Previous research has indicated that protein provision is positively associated with survival.

METHODS

This was a prospective observational study of all patients receiving CRRT for greater than 48 h at our tertiary care institution. Patients with inborn errors of metabolism were excluded. Data collection included energy, protein, and fluid volume intakes, anthropometrics, feeding modality, and route of nutrition intake.

RESULTS

Forty-one patients 9 ± 6.8 years of age, 66% male, received CRRT over a 10-month time period. CRRT treatment was 17.3 ± 25 days. Forty-one percent were malnourished via anthropometric criteria at CRRT start. Median protein delivery was 2 g/kg/day (IQR 1.4-2.5). Fifty-one percent received a combination of parenteral nutrition (PN) and enteral/oral feedings (EN), 34% received only PN, and 12% received only EN. Percentage of time meeting protein goals by modality was 27.6%, 34.6%, and 65.3% for those patients receiving solely EN, PN, and EN + PN combination, respectively. When weaned to only EN support from combination PN + EN, the average percentage of time protein goals were met decreased to 20.5% (p < 0.01).

CONCLUSIONS

Without PN, patients on enteral/oral nutrition support fail to meet appropriate protein prescription. Transition of parenteral to enteral feeds was identified as a period of nutritional risk in children receiving CRRT.

New modes of continuous renal replacement therapy using a refiltering technique to reduce micronutrient loss

INTRODUCTION

Micronutrient depletion is a major drawback of high-dose continuous renal replacement therapy (CRRT). We tested two novel CRRT modes, double-filtration hemofiltration (DHF) and dialysate-recycling hemodiafiltration (DHDF), aimed at reducing micronutrient loss while maintaining a high clearance rate of midsized solutes comparable to that of high-volume hemofiltration (HVHF).

METHODS

Forty patients with renal failure requiring CRRT were randomly assigned to receive predilutional standard-volume hemofiltration (SVHF, effluent rate 35 mL/kg/h), predilutional HVHF (100 mL/kg/h), DHF (35 mL/kg/h), and DHDF (30 mL/kg/h). In the two novel modes of CRRT, part of the high-volume primary effluent fluid produced by a high-flux filter (AV600S) was refiltered by two low-flux filters (15 L) for recycling as replacement fluid in DHF and dialysate in DHDF, while the remainder was discarded as final effluent fluid. Specimens were collected for measurement of trace elements, folic acid, amino acids (AAs), β2-microglobulin, cystatin C, and creatinine and for calculation of solute clearance.

FINDINGS

The clearance of 17 AAs, phosphorus, folic acid, copper, and zinc by DHF and DHDF was much lower than that by HVHF and comparable to that by SVHF. The estimated amount of AA loss by SVHF, HVHF, DHF, and DHDF was 10.3 (7.2-13.4) g/d, 22.1 (17.8-24.0) g/d, 10.6 (8.6-14.0) g/d, and 10.0 (8.6-11.4) g/d, respectively. Clearance of cystatin C and β2-microglobulin by DHF and DHDF was much greater than that by SVHF and equal to that by HVHF.

DISCUSSION

Compared to HVHF, DHF, and DHDF have an equal capacity for removal of large solutes but show substantially reduced micronutrient loss.

Quality Improvement Bedside Rounding Audits Enhance Protein Provision for Pediatric Patients Receiving Continuous Renal Replacement Therapy

OBJECTIVES

Describe quality improvement process improvements in protein delivery of continuous renal replacement therapy initiation.

DESIGN

Prospective study.

SETTING

PICU and cardiovascular ICU within a quaternary care children's hospital.

PATIENTS

PICU and cardiovascular ICU patients receiving continuous renal replacement therapy for greater than 48 hours. Inborn errors of metabolism were excluded.

INTERVENTIONS

Plan-Do-Study-Act cycles were initiated. Cycle 1 developed interdisciplinary quality improvement group continuously monitoring nutrition care with thrice weekly bedside safety rounds and protein prescriptions within nephrologist's notes. Cycle 2 included education to intensivists. Cycle 3 initiated monthly quality improvement meetings reviewing nutritional care goals.

MEASUREMENTS AND MAIN RESULTS

Primary outcome was percentage of time patients met protein goals in the first 5 days of continuous renal replacement therapy. Secondary outcome was percentage of time patients met protein goals for duration of continuous renal replacement therapy. Cohort (n = 55) mean age was 8.1 years (SD ± 6.8), 62% male, and 31% malnutrition at baseline. Percent of time meeting protein goals by day 5 was 22%, 33%, and 71% and percent of time meeting protein goals throughout was 35%, 39%, and 75% of groups 1, 2, and 3, respectively. Significant improvement occurred after Plan-Do-Study-Act 3 (group 2 vs group 3; p < 0.01) for primary and secondary outcomes.

CONCLUSIONS

Implementation of an interprofessional quality improvement team significantly decreased number of continuous renal replacement therapy days with unmet protein goals and improved protein delivery.

Metabolic Support of the Patient on Continuous Renal Replacement Therapy

Continuous renal replacement therapy (CRRT) is the modality of choice in critically ill patients with hemodynamic instability requiring renal replacement therapy. The goal of this review is to discuss an overview of CRRT types, components, and important considerations for nutrition support provision. Evidence basis for guidelines and our recommendations are reviewed. Nutrition support-related implications include the possibility of calorie gain with citrate-based anticoagulation, calorie loss with glucose-free replacement fluids and dialysate, and significant amino acid losses in effluent. We challenge nutrition support clinicians to develop a keen understanding of the specific CRRT modalities that are employed in their intensive care units and to be able to determine how the CRRT prescription may impact a patient's nutrition support prescription.

Neonatal Extracorporeal Life Support: A Review of Nutrition Considerations

Critically ill neonates who require extracorporeal life support have particular nutrition needs. These infants require prescription of aggressive, early nutrition support by knowledge providers. Understanding the unique metabolic demands and nutrition requirements of these fragile patients is paramount, particularly if additional therapies such as aggressive diuretic regimens or continuous renal replacement therapy are used concurrently. Although the American Society for Parenteral and Enteral Nutrition has published guidelines for this population, a review of each nutrition component is warranted because few studies exist specific to this population. Long-term complications in survivors of neonatal extracorporeal life support, particularly in patients with select diagnoses such as congenital diaphragmatic hernia, can be significant and must be recognized and anticipated. This review focuses on recognizing the nutrition needs of neonatal patients requiring extracorporeal life support, appraising the available data to guide selection of an appropriate mode of nutrition delivery, and describing the anticipated long-term nutrition implications of extracorporeal life support provision during the neonatal period.

Vitamin and trace element deficiencies in the pediatric dialysis patient

Pediatric dialysis patients are at risk of nutritional illness secondary to deficiencies in water-soluble vitamins and trace elements. Unlike 25-OH vitamin D, most other vitamins and trace elements are not routinely monitored in the blood and, consequently, the detection of any deficiency may not occur until significant complications develop. Causes of vitamin and trace element deficiency in patients on maintenance dialysis patient are multifactorial, ranging from diminished nutritional intake to altered metabolism as well as dialysate-driven losses of water-soluble vitamins and select trace elements. In this review we summarize the nutritional sources of key water-soluble vitamins and trace elements with a focus on the biological roles and clinical manifestations of their respective deficiency to augment awareness of potential nutritional illness in pediatric patients receiving maintenance dialysis. The limited pediatric data on the topic of clearance of water-soluble vitamins and trace elements by individual dialysis modality are reviewed, including a brief discussion on clearance of water-soluble vitamins and trace elements with continuous renal replacement therapy.

Micronutrient Alterations During Continuous Renal Replacement Therapy in Critically Ill Adults: A Retrospective Study

BACKGROUND

Continuous renal replacement therapy (CRRT) is commonly used to provide renal replacement therapy in the intensive care unit. Limited published data suggest that CRRT may lead to depletion of water-soluble vitamins and trace elements. The goal of this study was to identify the incidence of trace element and vitamin deficiencies in critically ill patients during CRRT.

MATERIALS AND METHODS

This study is based on a retrospective chart review of patients who were referred to Emory University Hospital's nutrition support services and had at least 1 serum micronutrient level measured during CRRT (thiamin, pyridoxine, ascorbic acid, folate, zinc, and copper) between April 1, 2009, and June 1, 2012.

RESULTS

Seventy-five patients were included in the study. Nine of 56 patients (16%) had below-normal whole blood thiamin concentrations, and 38 of 57 patients (67%) had below-normal serum pyridoxine levels. Serum ascorbic acid and folate deficiencies were identified among 87% (13 of 15) and 33% (3 of 9) of the study patients, respectively. Nine of 24 patients had zinc deficiency (38%), and 41 of 68 patients had copper deficiency (60%). Of the 75 total subjects, 60 patients (80%) had below-normal levels of at least 1 of the micronutrients measured.

CONCLUSIONS

The incidence of various micronutrient deficiencies in critically ill patients who required CRRT was higher than previously reported. Prospective studies are needed to determine the impact of CRRT on micronutrient status and the potential clinical and metabolic efficacy of supplementation in the intensive care unit setting.

Elimination Rates of Electrolytes, Vitamins, and Trace Elements during Continuous Renal Replacement Therapy with Citrate Continuous Veno-Venous Hemodialysis: Influence of Filter Lifetime

BACKGROUND/AIMS

During continuous renal replacement therapy, relevant losses of nutritional substrates, vitamins, and trace elements via the filter may occur. We investigated filter lifetime efficiency during a 72-h treatment period.

METHODS

This prospective study included 40 patients undergoing citrate continuous veno-venous hemodialysis (CVVHD). The elimination rates were measured at 24, 48, and 72 h. To assess the influence of filter lifetime, we determined substrate loss every 24 h over a 72-h interval.

RESULTS

Filter lifetime did not affect the loss of ionized calcium, inorganic phosphate, magnesium, zinc, folic acid, and vitamin B12. Nevertheless, we did observe clinically significant loss of ionized calcium and inorganic phosphate during CVVHD that required supplementation.

CONCLUSIONS

CVVHD leads to significant loss of ionized calcium and inorganic phosphate that is independent of the filter lifetime.

Trace elements in patients on continuous renal replacement therapy

PURPOSE

Intensive care patients with acute kidney injury (AKI), treated with continuous renal replacement therapy (CRRT) are at great risk for disturbances in plasma levels of trace elements due to the underlying illness, AKI, and dialysis. This study was performed to increase our knowledge regarding eight different trace elements during CRRT.

METHODS

Thirty one stable patients with AKI, treated with CRRT, were included in the study. Blood, plasma and effluent samples were taken at the start of the study and 36 ± 12 h later. A group of 48 healthy volunteers were included as controls and exposed to one fasting blood sample. Samples were analysed for trace elements (Cr, Cu, Mn, Co, Zn, Rb, Mo, Se) and standard blood chemistry.

RESULTS

Blood and plasma levels of selenium and rubidium were significantly reduced while the levels of chromium, cobalt, and molybdenum were significantly increased in the study group vs. healthy volunteers. There was an uptake of chromium, manganese, and zinc. Molybdenum mass balance was around zero. For selenium, copper, and rubidium there were a marked loss.

CONCLUSIONS

The low levels of selenium and rubidium in blood and plasma from CRRT patients, together with the loss via CRRT effluent, raises the possibility of the need for selenium supplementation in this group of patients, despite the unchanged levels during the short study period. Further investigations on the effect of additional administration of trace elements to CRRT patients would be of interest.

Dose Prescription and Delivery in Neonates With Congenital Heart Diseases Treated With Continuous Veno-Venous Hemofiltration

OBJECTIVES

Renal replacement therapy may be required for acute kidney injury treatment in neonates with complex cardiac conditions. Continuous veno-venous hemofiltration is applied safely in this population but no published recommendations for dose prescription in neonates currently exist. The aim of our study was to evaluate the effects of a relatively small dialysis dose on critically ill neonates.

DESIGN

Retrospective analysis of clinical charts.

SETTING

Pediatric Cardiac ICU.

PATIENTS

Ten critically ill neonates with severe acute kidney injury were analyzed. The primary indication for continuous veno-venous hemofiltration initiation was severe fluid overload with oligoanuria.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The median (range) age and weight were 3 days (1-12 d) and 2.6 kg (2.1-4.2 kg), respectively, whereas the median continuous veno-venous hemofiltration duration was 17 days (3-63 d). Median prescribed blood flow rate, replacement fluid rate, and net ultrafiltration rate were 12 mL/min (9-50 mL/min), 100 mL/hr (40-200 mL/hr), and 20 mL/hr (5-45 mL/hr), respectively. The median effluent-based continuous veno-venous hemofiltration dose was 35 mL/kg/hr (11-66 mL/kg/hr), whereas the median delivered daily Kt/V per session (24 hr) was 0.5 (0.01-1.8). However, for treatment sessions lasting less than or equal to 12 versus greater than or equal to 12 hours per session, the median prescribed effluent dose was 41 (11-66) and 32 (17-60) mL/kg/hr, respectively (p = 0.06), whereas the delivered creatinine daily Kt/V values were 0.3 (0.01-0.9) and 0.9 (0.5-1.8), respectively (p < 0.0001). An inverse correlation was found between delivered daily Kt/V and the blood concentration differences of both creatinine (r = -0.3; p = 0.0093) and urea (r = -0.3; p = 0.0028) measured at the end and the beginning of a 24-hour treatment. The decrease of creatinine concentration was significantly greater during 24-hour treatment sessions with a delivered daily Kt/V greater than 0.9 than during those with daily Kt/V less than 0.9.

CONCLUSIONS

Based on these findings, we propose on a provisional basis the use of daily Kt/V as a measure of continuous renal replacement therapy adequacy for critically ill neonates.

Low serum selenium is associated with the severity of organ failure in critically ill children

BACKGROUND & AIMS

Low concentration of serum selenium is associated with the inflammatory response and multiple organ failure in adult ICU-patients. Critically ill children are less well characterized. In this study, serum selenium concentration and its possible relation to multiple organ failure as well as glutathione status was investigated in pediatric intensive care (PICU) patients.

METHODS

A prospective consecutive cohort of critically ill children (n = 100) admitted to the PICU of a tertiary university hospital, and in addition an age stratified reference group of healthy children (n = 60) were studied. The concentrations of serum selenium and reduced and total glutathione were determined at admission and at day 5 for patients still in the PICU.

RESULTS

Low concentration of serum selenium as well as a high-reduced fraction of glutathione (GSH/tGSH) was associated with multiple organ failure (p < 0.001 and p < 0.01) respectively. A correlation between low serum selenium concentration and high-reduced fraction of glutathione (GSH/tGSH) was also seen (r = -0.19 and p = 0.03). The serum selenium concentrations in the pediatric reference group in a selenium poor area were age dependent with lower concentrations in infants as compared to older children (p < 0.001).

CONCLUSIONS

Both low serum selenium concentration and high reduced fraction of glutathione (GSH/tGSH) were associated with the development of multiple organ failure. The association between low serum selenium concentration and high fraction of reduced glutathione in whole blood favour the hypothesis that selenium is of critical importance for the scavenge capacity of glutathione peroxidase (GPX).

Nutritional management in the critically ill child with acute kidney injury: a review

Acute kidney injury (AKI) in critically ill children is frequently a component of the multiple organ failure syndrome. It occurs within the framework of the severe catabolic phase determined by critical illness and is intensified by metabolic derangements. Nutritional support is a must for these children to improve outcomes. Meeting the special nutritional needs of these children often requires nutritional supplementation by either the enteral or the parenteral route. Since critically ill children with AKI comprise a heterogeneous group of subjects with varying nutrient needs, nutritional requirements should be frequently reassessed, individualized and carefully integrated with renal replacement therapy. This article is a state-of-the-art review of nutrition in critically ill children with AKI.

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.

Metabolism of albumin after continuous venovenous hemofiltration in patients with systemic inflammatory response syndrome

BACKGROUND

The systemic inflammatory response syndrome (SIRS) is characterized by a hypercatabolic state induced by inflammatory mediators. Continuous venovenous hemofiltration (CVVH) stabilizes the internal environment but also aggravates loss of amino acids. The effect of CVVH on protein dynamics is largely unknown. We adopted the stable isotopic tracer technology to investigate how CVVH changed serum albumin metabolism.

METHODS

Twenty SIRS patients were randomized into low- (2000 mL/h) and high- (4000 mL/h) volume CVVH groups according to the rate of replacement fluid. Eight patients with abdominal infection matched for age, sex, and laboratory index served as controls. Consecutive arterial blood samples were drawn during a primed-constant infusion of two stable isotopes to determine the albumin fractional synthesis rate (FSR) and fractional breakdown rate (FBR).

RESULTS

Before treatment, there was no significant difference of FSR and FBR among 3 groups. After CVVH, the albumin FSR in high- and low-volume groups was 7.75±1.08% and 7.30±0.89%, respectively, both higher than in the control (5.83±0.94%). There was no significant difference in albumin FBR after treatment.

CONCLUSIONS

Protein dynamic indicators could reflect protein synthesis and breakdown state directly and effectively. CVVH increased albumin synthesis, while the breakdown rate remained at a high level independently of the CVVH rate.

Regional citrate anticoagulation for pediatric CRRT using integrated citrate software and physiological sodium concentration solutions

BACKGROUND

In continuous renal replacement therapy (CRRT), regional citrate anticoagulation offers an attractive alternative to heparinization, especially for children with a high bleeding risk.

METHODS

We report on a new management approach to CRRT using integrated citrate software and physiological sodium concentration solutions. Convective filtration was performed with pre-filter citrate anticoagulation using an 18 mmol/L citrate solution and a post-filter replacement fluid. The citrate flow rate was automatically adjusted to the blood flow rate by means of integrated citrate software. Similarly, calcium was automatically infused into children to maintain their blood calcium levels within normal range.

RESULTS

Eleven CRRT sessions were performed (330 h) in seven critically ill children aged 3-15 years (extreme values 15-66 kg). Disease categories included sepsis with multiorgan dysfunction (n = 2) and hemolytic uremic syndrome (n = 5). Median effluent dose was 2.1 (extreme values 1.7-3.3) L/h/1.73 m2. No session had to be stopped because of metabolic complications. Calcium levels, both in the circuits and in the circulating blood of the children, remained stable and secure.

CONCLUSIONS

Regional citrate anticoagulation can be used in children with a body weight of >15 kg using integrated citrate software and commercially available solutions with physiological sodium concentrations in a safe, effective and convenient procedure.

Amino acid concentrations in critically ill children following cardiac surgery*

OBJECTIVE

Guidelines for administering amino acids to critically ill children are largely based on uncontrolled observational studies and expert opinion, without support from rigorous outcome studies. Also, data on circulating amino acid concentrations during critical illness are scarce. We thoroughly studied the time profiles of circulating amino acid concentrations in critically ill children who received standard nutritional care according to international guidelines.

DESIGN

This is a subanalysis of pediatric critically ill patients included in a large (n = 700) randomized controlled study on intensive insulin therapy.

SETTING

The study was conducted at a university hospital PICU.

PATIENTS

We studied 100 patients in PICU for at least 3 days following cardiac surgery.

INTERVENTIONS

Patients were assigned to intensive insulin therapy targeting normal-for-age fasting blood glucose concentrations or insulin infusion only to prevent excessive hyperglycemia.

MEASUREMENTS AND MAIN RESULTS

Plasma amino acid concentrations were measured at admission, day 3, and day 7 in PICU. At admission, the concentrations of most amino acids were comparable to those reported for healthy children. Total amino acid concentrations remained stable during ICU stay, but individual amino acids showed different time profiles with eight of them showing an increase and five a decrease. Nonsurviving children had higher total amino acid concentrations and individual amino acids compared with survivors at admission and/or during ICU stay. Intensive insulin therapy lowered the concentrations of total amino acids and several individual amino acids. Neonates showed somewhat different amino acid profiles with rather increased concentrations from baseline with time in ICU for total amino acids and several individual amino acids as compared with older infants and children.

CONCLUSIONS

Circulating amino acid concentrations in critically ill children after cardiac surgery differ according to survival status, blood glucose control with intensive insulin therapy, and age.

Protein/energy debt in critically ill children in the pediatric intensive care unit: acute kidney injury as a major risk factor

Acute kidney injury (AKI) is common in pediatric intensive care unit (PICU) patients. In this clinical setting, the risk of protein-energy wasting is high because of the metabolic derangements of the uremic syndrome, the difficulties in nutrient needs estimation, and the possible negative effects of renal replacement therapy itself on nutrient balance. No specific guidelines on nutritional support in PICU patients with AKI are currently available. The present review is aimed at evaluating the role of AKI as a risk condition for inadequate protein/energy intake in these patients, on the basis of literature data on quantitative aspects of nutritional support in PICU. Current evidence suggests that a relevant protein/energy debt, a widely accepted concept in the literature on adult intensive care unit patients with its negative implications for patients' major outcomes, is also likely to develop in pediatric critically ill patients, and that AKI represents a key factor for its development.

Advances in pediatric renal replacement therapy

Advances in the understanding and clinical application of hemodialysis, peritoneal dialysis, and continuous renal replacement therapy have resulted in strategies designed to further improve their safety and efficacy. These advances have been particularly important to children, in whom a variety of clinical and technical issues must be taken into consideration for optimum dialysis across a broad spectrum of patient size and need. This manuscript reviews recent data pertaining to the use of renal replacement therapy, with an emphasis on those aspects of dialysis management that are especially pertinent to pediatric ESRD and acute kidney injury care.

Does online hemodiafiltration lead to reduction in trace elements and vitamins?

Hemodiafiltration (HDF) has been reported to improve nutritional intake, but as it increases convective losses, it could also increase micronutrient loss. We prospectively audited the effect of HDF on vitamin B12, zinc and selenium. Thirty-four patients dialyzing (T/Th/Sa) switched to HDF, and 44 dialyzing (M/W/F) remained on high-flux hemodialysis (HD) and were followed for 12 months. Dialysis adequacy, weight, hemoglobin, and serum albumin did not differ between the groups and did not change over 12 months' follow up. Similarly, vitamin B12 did not differ: HDF, 443 (325-682) ng/mL HD vs. 478 (327-690) ng/mL HDF; 6 months, 513 (351-664) ng/mL vs. 460 (379-647) ng/mL; or 12 months, 444 (317-617) ng/mL vs. 492 (323-644) ng/mL. And no patient had subnormal values. Folate levels, in those not taking supplements, were also stable (start, 6.2 ± 0.7 μg/L HD vs. 7.2 ± 1.0 μg/L HDF; 12 months, 6.5 ± 0.9 μg/L vs. 10.9 ± 2.4 μg/L). Serum zinc was subnormal in 50% prior to switching to HDF, 10.4 ± 0.4 μmol/L, but did not fall with HDF 10.2 ± 0.3 μmol/L; similarly, selenium was low in 49% prior to switching to HDF, 0.77 ± 0.06 μmol/L, but remained stable on HDF, 0.82 ± 0.06 μmol/L. Although HDF adds convective clearance to standard hemodialysis, it does not lead to a reduction in vitamin B12, folate, zinc, or selenium. However, half of this dialysis cohort had low levels of both zinc and selenium.