Profile of Fluid Exposure and Recognition of Fluid Overload in Critically Ill Children

An update on the role of fluid overload in the prediction of outcome in acute kidney injury

Over the past two decades, our understanding of the impact of acute kidney injury, disorders of fluid balance, and their interplay have increased significantly. In recent years, the epidemiology and impact of fluid balance, including the pathologic state of fluid overload on outcomes has been studied extensively across multiple pediatric and neonatal populations. A detailed understating of fluid balance has become increasingly important as it is recognized as a target for intervention to continue to work to improve outcomes in these populations. In this review, we provide an update on the epidemiology and outcomes associated with fluid balance disorders and the development of fluid overload in children with acute kidney injury (AKI). This will include a detailed review of consensus definitions of fluid balance, fluid overload, and the methodologies to define them, impact of fluid balance on the diagnosis of AKI and the concept of fluid corrected serum creatinine. This review will also provide detailed descriptions of future directions and the changing paradigms around fluid balance and AKI in critical care nephrology, including the incorporation of the sequential utilization of risk stratification, novel biomarkers, and functional kidney tests (furosemide stress test) into research and ultimately clinical care. Finally, the review will conclude with novel methods currently under study to assess fluid balance and distribution (point of care ultrasound and bioimpedance).

Evaluating fluid overload in critically ill children

PURPOSE OF REVIEW

To review the evaluation and management of fluid overload in critically ill children.

RECENT FINDINGS

Emerging evidence associates fluid overload, i.e. having a positive cumulative fluid balance, with adverse outcome in critically ill children. This is most likely the result of impaired organ function due to increased extravascular water content. The combination of a number of parameters, including physical, laboratory and radiographic markers, may aid the clinician in monitoring and quantifying fluid status, but all have important limitations, in particular to discriminate between intra- and extravascular water volume. Current guidelines advocate a restrictive fluid management, initiated early during the disease course, but are hampered by the lack of high quality evidence.

SUMMARY

Recent advances in early evaluation of fluid status and (tailored) restrictive fluid management in critically ill children may decrease complications of fluid overload, potentially improving outcome. Further clinical trials are necessary to provide the clinician with solid recommendations.

Fluid assessment, fluid balance, and fluid overload in sick children: a report from the Pediatric Acute Disease Quality Initiative (ADQI) conference

BACKGROUND

The impact of disorders of fluid balance, including the pathologic state of fluid overload in sick children has become increasingly apparent. With this understanding, there has been a shift from application of absolute thresholds of fluid accumulation to an appreciation of the intricacies of fluid balance, including the impact of timing, trajectory, and disease pathophysiology.

METHODS

The 26th Acute Disease Quality Initiative was the first to be exclusively dedicated to pediatric and neonatal acute kidney injury (pADQI). As part of the consensus panel, a multidisciplinary working group dedicated to fluid balance, fluid accumulation, and fluid overload was created. Through a search, review, and appraisal of the literature, summative consensus statements, along with identification of knowledge gaps and recommendations for clinical practice and research were developed.

CONCLUSIONS

The 26th pADQI conference proposed harmonized terminology for fluid balance and for describing a pathologic state of fluid overload for clinical practice and research. Recommendations include that the terms daily fluid balance, cumulative fluid balance, and percent cumulative fluid balance be utilized to describe the fluid status of sick children. The term fluid overload is to be preserved for describing a pathologic state of positive fluid balance associated with adverse events. Several recommendations for research were proposed including focused validation of the definition of fluid balance, fluid overload, and proposed methodologic approaches and endpoints for clinical trials.

Pattern of Fluid Overload and its Impact on Mortality Among Mechanically Ventilated Children: Secondary Analysis of the ReLiSCh Trial

OBJECTIVES

To assess the pattern of fluid overload (FO) and its impact on mortality among mechanically ventilated children.

METHODS

In this secondary analysis of an open-label randomized controlled trial (ReLiSCh trial, October 2020-September 2021), hemodynamically stable mechanically ventilated children (n = 100) admitted to a tertiary level pediatric intensive care unit (PICU) in North India were enrolled. The primary outcome was pattern of FO (FO% >10% and cumulative FO% from day 1-7); and secondary outcomes were pattern of FO among survivors and non-survivors, and prescription practices of maintenance fluid.

RESULTS

The median (IQR) age was 3.5 (0.85-7.5) y and 57% were males. Common diagnoses were pneumonia (27%), scrub typhus (14%), Landry-Guillain-Barré syndrome (9%), dengue (8%), central nervous system infections (7%) and staphylococcal sepsis (6%). Common organ dysfunction included acute respiratory distress syndrome (ARDS) (41%), shock (38%), and acute kidney injury (AKI) (9%). The duration PICU stay was 11 (7-17) d and mortality was 12%. The FO% >10% was noted in 19% children; and there was significant increase in cumulative FO% from day 1-7 [1.2 (0.2-2.6)% to 8.5 (1.7-14.3)%, (p = 0.000)]. Among non-survivors, higher proportion had FO% >10% (66.7% vs. 12.5%, p 0.0001); and trend towards higher cumulative FO% on first seven days. From day 1-7, the percentage of maintenance fluid received increased from 60 (50-71)% to 70 (60-77)% (p = 0.691).

CONCLUSIONS

One-fifth of mechanically ventilated children had FO% >10% and there was significant increase in cumulative FO% from day 1-7. Non-survivors had significantly higher degree of FO.

Nonresuscitation Fluid Accumulation and Outcomes After Pediatric Cardiac Surgery: Single-Center Retrospective Cohort Study

OBJECTIVES

Postoperative patients after congenital cardiac surgery are at high risk of fluid overload (FO), which is known to be associated with poor outcomes. "Fluid creep," or nonresuscitation IV fluid in excess of maintenance requirement, is recognized as a modifiable factor associated with FO in the general PICU population, but has not been studied in congenital cardiac surgery patients. Our objective was to characterize fluid administration after congenital cardiac surgery, quantify fluid creep, and the association between fluid creep, FO, and outcome.

DESIGN

Retrospective, observational cohort study.

SETTING

Single-center urban mixed-medical and cardiac PICU.

PATIENTS

Patients admitted to the PICU after cardiac surgery between January 2010 and December 2020.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

There were 1,459 postoperative encounters with 1,224 unique patients. Total fluid intake was greater than maintenance requirements on 3,103 of 4,661 patient days (67%), with fluid creep present on 2,624 patient days (56%). Total nonresuscitation intake was higher in patients with FO (defined as cumulative fluid balance 10% above body weight) versus those without. Fluid creep was higher among patients with FO than those without for each of the first 5 days postoperatively. Each 10 mL/kg of fluid creep in the first 24 hours postoperatively was associated with 26% greater odds of developing FO (odds ratio [OR] 1.26; 95% CI, 1.17-1.35) and 17% greater odds of mortality (OR 1.17; 95% CI, 1.05-1.30) after adjusting for risk of mortality based on surgical procedure, age, and day 1 resuscitation volume. Increasing fluid creep in the first 24 hours postoperatively was associated with increased postoperative duration of mechanical ventilation and PICU length of stay.

CONCLUSIONS

Fluid creep is present on most postoperative days for pediatric congenital cardiac surgery patients, and fluid creep is associated with higher-risk procedures. Fluid creep early in the postoperative PICU stay is associated with greater odds of FO, mortality, length of mechanical ventilation, and PICU length of stay. Fluid creep may be under-recognized in this population and thus present a modifiable target for intervention.

REstrictive versus StandarD FlUid Management in Mechanically Ventilated ChildrEn Admitted to PICU: study protocol for a pilot randomised controlled trial (REDUCE-1)

INTRODUCTION

Intravenous fluid therapy is the most common intervention in critically ill children. There is an increasing body of evidence questioning the safety of high-volume intravenous fluid administration in these patients. To date, the optimal fluid management strategy remains unclear. We aimed to test the feasibility of a pragmatic randomised controlled trial comparing a restrictive with a standard (liberal) fluid management strategy in critically ill children.

METHODS AND ANALYSIS

Multicentre, binational pilot, randomised, controlled, open-label, pragmatic trial. Patients <18 years admitted to paediatric intensive care unit and mechanically ventilated at the time of screening are eligible. Patients with tumour lysis syndrome, diabetic ketoacidosis or postorgan transplant are excluded.

INTERVENTIONS

1:1 random assignment of 154 individual patients into two groups-restrictive versus standard, liberal, fluid strategy-stratified by primary diagnosis (cardiac/non-cardiac). The intervention consists of a restrictive fluid bundle, including lower maintenance fluid allowance, limiting fluid boluses, reducing volumes of drug delivery and initiating diuretics or peritoneal dialysis earlier. The intervention is applied for 48 hours postrandomisation or until discharge (whichever is earlier).

ENDPOINTS

The number of patients recruited per month and proportion of recruited to eligible patients are feasibility endpoints. New-onset acute kidney injury and the incidence of clinically relevant central venous thrombosis are safety endpoints. Fluid balance at 48 hours after randomisation is the efficacy endpoint. Survival free of paediatric intensive care censored at 28 days is the clinical endpoint.

ETHICS AND DISSEMINATION

Ethics approval was gained from the Children's Health Queensland Human Research Ethics Committee (HREC/21/QCHQ/77514, date: 1 September 2021), and University of Zurich (2021-02447, date: 17 March 2023). The trial is registered with the Australia New Zealand Clinical Trials Registry (ACTRN12621001311842). Open-access publication in high impact peer-reviewed journals will be sought. Modern information dissemination strategies will also be used including social media to disseminate the outcomes of the study.

TRIAL REGISTRATION NUMBER

ACTRN12621001311842.

PROTOCOL VERSION/DATE

V5/23 May 2023.

Restricted versus Usual/Liberal Maintenance Fluid Strategy in Mechanically Ventilated Children: An Open-Label Randomized Trial (ReLiSCh Trial)

OBJECTIVES

To assess the impact of restricted vs. usual/liberal maintenance fluid strategy on fluid overload (FO) among mechanically ventilated children.

METHODS

This open-label randomized controlled trial was conducted over a period of 1 y (October 2020-September 2021) in a Pediatric intensive care unit (PICU) in North India. Hemodynamically stable mechanically ventilated children were randomized to 40% (restricted group, n = 50) and 70-80% (usual/liberal group, n = 50) of maintenance fluids. The primary outcome was cumulative fluid overload percentage (FO%) on day 7. Secondary outcomes were FO% >10%; vasoactive inotropic score, sequential organ failure assessment score, pediatric logistic organ dysfunction score and oxygenation index from day 1-7; ventilation free days (VFDs) and PICU free days (PFDs) through day 28; and mortality.

RESULTS

The restricted group had statistically non-significant trend towards lower cumulative FO% at day 7 [7.6 vs. 9.5, p = 0.40]; and proportion of children with FO% >10% (12% vs. 26%, p = 0.21) as compared to usual/liberal group. The increase in FO% from day 1-7 was significant in usual/liberal group as compared to restricted group (p <0.001 and p = 0.134, respectively). Restricted group received significantly lower amount of fluid in the first 5 d; had significantly higher VFDs (23 vs. 17 d, p = 0.008) and PFDs (19 vs. 15 d, p = 0.007); and trend towards lower mortality (8% vs. 16%, p = 0.21).

CONCLUSIONS

Restricted as compared to usual/liberal maintenance fluid strategy among mechanically ventilated children was associated with a trend towards lower rate and severity of FO and mortality; and significantly lower fluid volume received, and higher VFDs and PFDs.

Gravity-assisted continuous flow peritoneal dialysis technique use in acute kidney injury in children: a randomized, crossover clinical trial

BACKGROUND

Our previously demonstrated continuous flow peritoneal dialysis (CFPD) technique in children with acute kidney injury (AKI), although effective, was manpower heavy and expensive due to the high-volume pumps required. The aim of this study was to develop and test a novel gravity-driven CFPD technique in children using readily available, inexpensive equipment and to compare this technique to conventional PD.

METHODS

After development and initial in vitro testing, a randomised crossover clinical trial was conducted in 15 children with AKI requiring dialysis. Patients received both conventional PD and CFPD sequentially, in random order. Primary outcomes were measures of feasibility, clearance and ultrafiltration (UF). Secondary outcomes were complications and mass transfer coefficients (MTC). Paired t-tests were used to compare PD and CFPD outcomes.

RESULTS

Median (range) age and weight of participants were 6.0 (0.2-14) months and 5.8 (2.3-14.0) kg, respectively. The CFPD system was easily and rapidly assembled. There were no serious adverse events attributed to CFPD. Mean ± SD UF was significantly higher on CFPD compared to conventional PD (4.3 ± 3.15 ml/kg/h vs. 1.04 ± 1.72 ml/kg/h; p < 0.001). Clearances for urea, creatinine and phosphate for children on CFPD were 9.9 ± 3.10 ml/min/1.73 m2, 7.9 ± 3.3 ml/min/1.73 m2 and 5.5 ± 1.5 ml/min/1.73 m2 compared to conventional PD with values of 4.3 ± 1.68 ml/min/1.73 m2, 3.57 ± 1.3 ml/min/1.73 m2 and 2.53 ± 0.85 ml/min/1.73 m2, respectively (all p < 0.001).

CONCLUSION

Gravity-assisted CFPD appears to be a feasible and effective way to augment ultrafiltration and clearances in children with AKI. It can be assembled from readily available non-expensive equipment. A higher resolution version of the Graphical abstract is available as Supplementary information.

A Clinical Score for Quantifying Edema in Mechanically Ventilated Children With Congenital Heart Disease in Intensive Care

Standardized clinical measurements of edema do not exist.

OBJECTIVES

To describe a 19-point clinical edema score (CES), investigate its interobserver agreement, and compare changes between such CES and body weight.

DESIGN SETTING AND PARTICIPANTS

Prospective observational study in a tertiary PICU of mechanically ventilated children with congenital heart disease.

MAIN OUTCOMES AND MEASURES

Differences in the median CES between observer groups.

RESULTS

We studied 61 children, with a median age of 8.0 days (interquartile range, 1.0-14.0 d). A total of 539 CES were performed by three observer groups (medical 1 [reference], medical 2, and bedside nurse) at 0, 24, and 48 hours from enrollment. Overall, there was close agreement between observer groups in mean, median, and upper quartile of CES scores, with least agreement observed in the lower quartile of scores. Across all quartiles of CES, after adjusting for baseline weight, cardiac surgical risk, duration of cardiopulmonary bypass, or peritoneal dialysis during the study, observer groups returned similar mean scores (medical 2: 25th centile +0.1 [95% CI, -0.2 to 0.5], median +0.6 [95% CI, -0.4 to 1.5], 75th centile +0.1 [95% CI, -1.1 to 1.4] and nurse: 25th centile +0.5 [95% CI, 0.0-0.9], median +0.7 [95% CI, 0.0-1.5], 75th centile -0.2 [95% CI, -1.3 to 1.0]) Within a multivariable mixed-effects linear regression model, including adjustment for baseline CES, each 1 point increase in CES was associated with a 12.1 grams (95% CI, 3.2-21 grams) increase in body weight.

CONCLUSIONS AND RELEVANCE

In mechanically ventilated children with congenital heart disease, three groups of observers tended to agree when assessing overall edema using an ordinal clinical score assessed in six body regions, with agreement least at low edema scores. An increase in CES was associated with an increase in body weight, suggesting some validity for quantifying edema. Further exploration of the CES as a rapid clinical tool is indicated.

Fluid management of the critically Ill child

PURPOSE OF REVIEW

This review summarizes current literature pertaining to fluid management for critically ill children. It includes an overview on crystalloid fluid used throughout the critical illness course, management of fluid output and complications with fluid overload.

RECENT FINDINGS

Observational paediatric studies and adult randomized trials show mixed results regarding risk of mortality and kidney injury with 0.9% saline and crystalloid fluid. A recent adult randomized trial suggests that a fluid restrictive strategy may be well tolerated in critically ill adults with septic shock, but further randomized trials are needed in paediatrics. Fluid overload has been associated with increased morbidity and mortality. Trials exploring ways to decrease fluid accumulation must be done in paediatrics.

SUMMARY

Additional high-quality studies are needed to precisely define the type, timing and rate of intravenous fluid critically ill children should receive throughout their clinical illness course.

Fluid Removal in Children on Continuous Renal Replacement Therapy Improves Organ Dysfunction Score

The objective is to assess impact of fluid removal on improvement in organ function in children who received continuous renal replacement therapy (CRRT) for management of acute kidney injury and/or fluid overload (FO). A retrospective review of eligible patients admitted to a tertiary level intensive care unit over a 3-year period was performed. Improvement in nonrenal organ function, the primary outcome, was defined as decrease in nonrenal component of Pediatric Logistic Organ Dysfunction (PELOD) score on day 3 of CRRT. The cohort was categorized into Group 1 (improvement) and Group 2 (no improvement or worsening) in nonrenal PELOD score. Multivariable logistic regression analysis was performed to identify independent predictors. A higher PELOD score at CRRT initiation (odds ratio [OR]: 1.11, 95% confidence interval [CI]: 1.05, 1.18, p < 0.001), belonging to infant-age group (OR: 4.53, 95% CI: 4.40, 5.13, p = 0.02) and greater fluid removal during initial 3 days of CRRT (OR: 1.05, 95% CI: 1.01, 1.10, p = 0.01) were associated with an improvement in nonrenal PELOD score at day 3 of CRRT. FO at CRRT initiation (OR: 0.66, 95% CI: 0.46, 0.93, p = 0.02) and having an underlying oncologic diagnosis (OR: 0.28, 95% CI: 0.09, 0.85, p = 0.03) were associated with worsening of nonrenal PELOD score at day 3 of CRRT. Careful consideration of certain modifiable patient and/or fluid removal kinetic factors may have an impact on outcomes.

Kidney Injury in Children after Hematopoietic Stem Cell Transplant

Hematopoietic cell transplant (HCT), used for treatment of many malignant and non-malignant pediatric diseases, is associated with serious complications, limiting this therapy’s benefit. Acute kidney injury (AKI), seen often after HCT, can occur at different stages of the transplant process and contributes to morbidity and mortality after HCT. The etiology of AKI is often multifactorial, including kidney hypoperfusion, nephrotoxicity from immunosuppressive and antimicrobial agents, and other transplant-related complications such as transplant-associated thrombotic microangiopathy and sinusoidal obstructive syndrome. Early recognition of AKI is crucial to prevent further AKI and associated complications. Initial management includes identifying the etiology of AKI, preventing further kidney hypoperfusion, adjusting nephrotoxic medications, and preventing fluid overload. Some patients will require further support with kidney replacement therapy to manage fluid overload and AKI. Biomarkers of AKI, such as neutrophil gelatinase-associated lipocalin can aid in detecting AKI before a rise in serum creatinine, allowing earlier intervention. Long-term kidney dysfunction is also prominent in this population. Therefore, long-term follow-up and monitoring of renal function (glomerular filtration rate, microalbuminuria) is required along with management of hypertension, which can contribute to chronic kidney disease.

A quality initiative to improve recognition of fluid overload among pediatric ICU patients requiring continuous kidney replacement therapy: preliminary results

BACKGROUND

Initiation of continuous kidney replacement therapy (CKRT) greater than 20% fluid overload is associated with increased morbidity and mortality. We aimed to reduce the number of patients initiated on CKRT greater than 20% fluid overload by 50% in one year by implementation of a quality improvement initiative.

METHODS

This is a prospective quality improvement study set in a pediatric ICU of an urban children's hospital of patients initiated on CKRT over 2 years. The intervention included creation of an electronic health record order for daily calculation of net percent fluid overload, incorporation into daily rounds, and education programs tailored to physicians and bedside nursing. We measured adherence with the new order set, percent fluid overload at CKRT initiation, days on CKRT, timing of first nephrology consultation, and death prior to discharge.

RESULTS

A total of 32% of patients were initiated on CKRT greater than 20% fluid overload pre-initiative and 9% post-initiative, a 72% reduction over 13 months. Patients initiated on CKRT greater than 20% fluid overload had median CKRT course of 8 (IQR 4-14) vs. 22 days (IQR 13.5-62).

CONCLUSION

Creating a system using EHR with education may reduce initiation of CKRT after development of severe fluid overload. A higher resolution version of the Graphical abstract is available as Supplementary information.

Fluid balance in pediatric critically ill patients (with and without kidney dysfunction)

PURPOSE OF REVIEW

The issues of fluid balance and fluid overload are currently considered crucial aspects of pediatric critically ill patients' care.

RECENT FINDINGS

This review describes current understanding of fluid management in critically ill children in terms of fluid balance and fluid overload and its effects on patients' outcomes. The review describes current evidence surrounding definitions, monitoring, and treatment of positive fluid balance. In particular, the review focuses on specific patient conditions, including perioperative cardiac surgery, severe acute respiratory failure, and extracorporeal membrane oxygenation therapy, as the ones at highest risk of developing fluid overload and poor clinical outcomes. Gaps in understanding include specific thresholds at which fluid overload occurs in all critically ill children or specific populations and optimal timing of decongestion of positive fluid balance.

SUMMARY

Current evidence on fluid balance in critically ill children is mainly based on retrospective and observational studies, and intense research should be recommended in this important field. In theory, active decongestion of patients with fluid overload could improve mortality and other clinical outcomes, but randomized trials or advanced pragmatic studies are needed to better understand the optimal timing, patient characteristics, and tools to achieve this.

Variability in Clinician Awareness of Intravenous Fluid Administration in Critical Illness: A Prospective Cohort Study

Intravenous (IV) fluids are commonly administered to critically ill children, but clinicians lack effective guidance for the correct dose and duration of therapy resulting in variation of prescribing habits which harm children. It is unknown if clinicians recognize the amount of IV fluid that patients receive. We aimed to determine clinician's accuracy in the identification of the volume of IV fluids patients will receive over the next 24 hours. Prospective cohort study enrolled all patients admitted to the pediatric intensive care unit (PICU) from May to August 2021 at the University of Michigan's C.S. Mott Children's Hospital PICU. For each patient, clinicians estimated the volume of IV fluid that patients will receive in the next 24 hours. The primary outcome was accuracy of the estimation defined as predicted volume of IV fluids versus actual volume administered within 10 mL/kg or 500 mL depending on patient's weight. We tested for differences in accuracy by clinician type using chi-square tests. There were 259 patients for whom 2,295 surveys were completed by 177 clinicians. Clinicians' estimates were accurate 48.8% of the time with a median difference of 10 (1–26) mL/kg. We found that accuracy varied between clinician type: bedside nurses were most accurate at 64.3%, and attendings were least accurate at 30.5%. PICU clinicians have poor recognition of the amount of IV fluids their patients will receive in the subsequent 24-hour period. Estimate accuracy varied by clinician's role and improved over time, which may suggest opportunities for improvement.

Intravenous maintenance fluid therapy practice in the pediatric acute and critical care settings: a European and Middle Eastern survey

The ideal fluid for intravenous maintenance fluid therapy (IV-MFT) in acutely and critically ill children is controversial, and evidence-based clinical practice guidelines are lacking and current prescribing practices remain unknown. We aimed to describe the current practices in prescribing IV-MFT in the context of acute and critically ill children with regard to the amount, tonicity, composition, use of balanced fluids, and prescribing strategies in various clinical contexts. A cross-sectional electronic 27-item survey was emailed in April-May 2021 to pediatric critical care physicians across European and Middle East countries. The survey instrument was developed by an expert multi-professional panel within the European Society of Pediatric and Neonatal Intensive Care (ESPNIC). A total of 154 respondents from 35 European and Middle East countries participated (response rate 64%). Respondents were physicians in charge of acute or critically ill children. All respondents indicated they routinely use a predefined formula to prescribe the amount of IV-MFT and considered fluid balance monitoring very important in the management of acute and critically ill children. The use of balanced solution was preferred if there were altered serum sodium and chloride levels or metabolic acidosis. Just under half (42%, 65/153) of respondents believed balanced solutions should always be used. Respondents considered the use of isotonic IV solutions as important for acute and critically ill children. In terms of the indication and the composition of IV-MFT prescribed, responses were heterogeneous among centers. Almost 70% (107/154) respondents believed there was a gap between current practice and what they considered ideal IV-MFT due to a lack of guidelines and inadequate training of healthcare professionals.   Conclusions: Our study showed considerable variability in clinical prescribing practice of IV-MFT in acute pediatric settings across Europe and the Middle East. There is an urgent need to develop evidence-based guidelines for IV-MFT prescription in acute and critically ill children. What is Known: • The administration of maintenance intravenous fluid therapy is a standard of care for a lot of hospitalized children • Maintenance intravenous fluid therapy prescriptions are often based on Holliday and Segar's historical guidelines even if this practice has been associated with several complications. What is New: • This study provided information on the prescribing practice regarding fluid restriction, fluid tonicity, and balance. • This study showed considerable variability in clinical prescribing practice of intravenous maintenance fluid therapy across Europe and the Middle East.

Medication and Fluid Management of Pediatric Sepsis and Septic Shock

Sepsis is a life-threatening response to infection that contributes significantly to neonatal and pediatric morbidity and mortality worldwide. The key tenets of care include early recognition of potential sepsis, rapid intervention with appropriate fluids to restore adequate tissue perfusion, and empiric antibiotics to cover likely pathogens. Vasoactive/inotropic agents are recommended if tissue perfusion and hemodynamics are inadequate following initial fluid resuscitation. Several adjunctive therapies have been suggested with theoretical benefit, though definitive recommendations are not yet supported by research reports. This review focuses on the recommendations for medication and fluid management of pediatric sepsis and septic shock, highlighting issues related to antibiotic choices and antimicrobial stewardship, selection of intravenous fluids for resuscitation, and selection and use of vasoactive/inotropic medications. Controversy remains regarding resuscitation fluid volume and type, antibiotic choices depending upon infectious risks in the patient's community, and adjunctive therapies such as vitamin C, corticosteroids, intravenous immunoglobulin, and methylene blue. We include best practice recommendations based on international guidelines, a review of primary literature, and a discussion of ongoing clinical trials and the nuances of therapeutic choices.

Fluid Homeostasis and Diuretic Therapy in the Neonate

Understanding physiologic water balance and homeostasis mechanisms in the neonate is critical for clinicians in the NICU as pathologic fluid accumulation increases the risk for morbidity and mortality. In addition, once this process occurs, treatment is limited. In this review, we will cover fluid homeostasis in the neonate, explain the implications of prematurity on this process, discuss the complexity of fluid accumulation and the development of fluid overload, identify mitigation strategies, and review treatment options.

Non-resuscitation fluid in excess of hydration requirements is associated with higher mortality in critically ill children

BACKGROUND

Large volumes of non-resuscitation fluids are often administered to critically ill children. We hypothesize that excess maintenance fluid is a significant contributor to non-resuscitation fluid and that non-resuscitation fluid administered beyond hydration requirements is associated with worse clinical outcomes in critically ill children.

METHODS

We evaluated all patients admitted to two large urban pediatric intensive care units (PICU) between January 2010-August 2016 and January 2010-August 2018, respectively, who survived and remained in the hospital for at least 3 days following PICU admission. The primary outcome was in-hospital mortality. Association of excess fluid with outcomes was adjusted for confounders (age, Pediatric Risk of Mortality III score, study site, day 3 acute kidney injury, PICU era, resuscitation volume, and volume output) using multivariable regression.

RESULTS

We evaluated 14,483 patients; 52% received non-resuscitation fluid in excess of hydration requirements. Non-resuscitation fluid in excess of hydration requirements was associated with higher in-hospital mortality after adjustment for confounders (adjusted odds ratio 1.01 per 10 mL/kg in excess fluid, 95% confidence interval: 1.002-1.02).

CONCLUSIONS

Non-resuscitation fluid in excess of hydration requirements is associated with increased mortality in critically ill children. Excess maintenance fluid is a modifiable contributor to this fluid volume. Strategies to reduce excess maintenance fluids warrant further study.

IMPACT

Critically ill children frequently receive non-resuscitation fluid in excess of their estimated hydration requirements. Non-resuscitation fluid volume in excess of estimated hydration requirements is associated with higher morbidity and mortality in critically ill children. Critically ill children receive a large volume burden from maintenance fluid. Maintenance fluid represents a modifiable contributor of non-resuscitation fluid in excess of hydration requirements. Strategies focused on limitation of maintenance fluid warrant further study.

Controversies in paediatric acute kidney injury and continuous renal replacement therapy: can paediatric care lead the way to precision acute kidney injury medicine?

PURPOSE OF REVIEW

Paediatric patients represent a unique challenge for providers managing acute kidney injury (AKI). Critical care for these children requires a precise approach to assessment, diagnostics and management.

RECENT FINDINGS

Primarily based on observational data, large epidemiologic datasets have demonstrated a strong association between AKI prevalence (one in four critically ill children) and poor patient outcome. Drivers of AKI itself are multifactorial and the causal links between AKI and host injury remain incompletely defined, creating a management paradigm primarily supportive in nature. The previous decades of research have focused primarily on elucidating the population-level epidemiologic signal of AKI and use of renal replacement therapy (RRT), but in order to reverse the course of the AKI 'epidemic', future decades will require more attention to the individual patient. A patient-level approach to AKI in children will require sophisticated approaches to risk stratification, diagnostics and targeted utilization of therapies (both supportive and targeted towards drivers of injury).

SUMMARY

In this review, we will summarize the past, present and future of AKI care in children, discussing the ongoing work and future goals of a personalized approach to AKI medicine.

Latin American Consensus on the Management of Sepsis in Children: Sociedad Latinoamericana de Cuidados Intensivos Pediátricos [Latin American Pediatric Intensive Care Society] (SLACIP) Task Force: Executive Summary

OBJECTIVE

The aim of this study was to develop evidence-based recommendations for the diagnosis and treatment of sepsis in children in low- and middle-income countries (LMICs), more specifically in Latin America. Design: A panel was formed consisting of 27 experts with experience in the treatment of pediatric sepsis and two methodologists working in Latin American countries. The experts were organized into 10 nominal groups, each coordinated by a member. Methods: A formal consensus was formed based on the modified Delphi method, combining the opinions of nominal groups of experts with the interpretation of available scientific evidence, in a systematic process of consolidating a body of recommendations. The systematic search was performed by a specialized librarian and included specific algorithms for the Cochrane Specialized Register, PubMed, Lilacs, and Scopus, as well as for OpenGrey databases for grey literature. The GRADEpro GDT guide was used to classify each of the selected articles. Special emphasis was placed on search engines that included original research conducted in LMICs. Studies in English, Spanish, and Portuguese were covered. Through virtual meetings held between February 2020 and February 2021, the entire group of experts reviewed the recommendations and suggestions. Result: At the end of the 12 months of work, the consensus provided 62 recommendations for the diagnosis and treatment of pediatric sepsis in LMICs. Overall, 60 were strong recommendations, although 56 of these had a low level of evidence. Conclusions: These are the first consensus recommendations for the diagnosis and management of pediatric sepsis focused on LMICs, more specifically in Latin American countries. The consensus shows that, in these regions, where the burden of pediatric sepsis is greater than in high-income countries, there is little high-level evidence. Despite the limitations, this consensus is an important step forward for the diagnosis and treatment of pediatric sepsis in Latin America.

Renal angina index predicts fluid overload in critically ill children: an observational cohort study

Background

Fluid overload and acute kidney injury are common and associated with poor outcomes among critically ill children. The prodrome of renal angina stratifies patients by risk for severe acute kidney injury, but the predictive discrimination for fluid overload is unknown.

Methods

Post-hoc analysis of patients admitted to a tertiary care pediatric intensive care unit (PICU). The primary outcome was the performance of renal angina fulfillment on day of ICU admission to predict fluid overload ≥15% on Day 3.

Results

77/139 children (55%) fulfilled renal angina (RA+). After adjusting for covariates, RA+ was associated with increased odds of fluid overload on Day 3 (adjusted odds ratio (aOR) 5.1, 95% CI 1.23–21.2, p = 0.025, versus RA-). RA- resulted in a 90% negative predictive value for fluid overload on Day 3. Median fluid overload was significantly higher in RA+ patients with severe acute kidney injury compared to RA+ patients without severe acute kidney injury (% fluid overload on Day 3: 8.8% vs. 0.73%, p = 0.002).

Conclusion

Among critically ill children, fulfillment of renal angina was associated with increased odds of fluid overload versus the absence of renal angina and a higher fluid overload among patients who developed acute kidney injury. Renal angina directed risk classification may identify patients at highest risk for fluid accumulation. Expanded study in larger populations is warranted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02540-6.

Fluid Balance Management Informs Renal Replacement Therapy Use During Pediatric Extracorporeal Membrane Oxygenation: A Survey Report From the Kidney Intervention During Extracorporeal Membrane Oxygenation Group

Fluid overload (FO) and acute kidney injury (AKI) occur commonly in children supported with extracorporeal membrane oxygenation (ECMO). Continuous renal replacement therapy (CRRT) may be used to manage AKI and FO in children on ECMO. In 2012, our group surveyed ECMO centers to begin to understand the practice patterns around CRRT and ECMO. Since then, more centers are initiating ECMO for increasingly diverse indications and an increased volume of research quantifies the detrimental impacts of AKI and FO. We, therefore, investigated practice patterns of CRRT utilization during ECMO in children. A multi-point survey instrument was distributed to 116 international neonatal and pediatric ECMO centers. Sixty of 116 (51.7%) international neonatal and pediatric ECMO centers responded. All reports using CRRT on ECMO, compared with 75% from the 2012 survey. Eighty-five percent use CRRT to treat or prevent FO, an increased from 59%. The modality of CRRT therapy differed between in-line (slow continuous ultrafiltration, 84.4%) and machine-based (continuous venovenous hemodiafiltration, 87.3%) methods. Most (65%) do not have protocols for fluid management, AKI, or CRRT on ECMO. Trialing off CRRT is dictated by physician preference in 90% (54/60), with varying definitions of success. In this survey study, we found that CRRT use during pediatric ECMO has increased since 2012 with fluid management representing the predominant indication for initiation. Despite the expanded utilization of CRRT with ECMO, there remains significant practice variation in terms of method, modality, indication, the timing of initiation, fluid management, and discontinuation.

Early restrictive fluid resuscitation has no clinical advantage in experimental severe pediatric acute respiratory distress syndrome

Intravenous fluids are widely used to treat circulatory deterioration in pediatric acute respiratory distress syndrome (PARDS). However, the accumulation of fluids in the first days of PARDS is associated with adverse outcome. As such, early fluid restriction may prove beneficial, yet the effects of such a fluid strategy on the cardiopulmonary physiology in PARDS are unclear. In this study, we compared the effect of a restrictive with a liberal fluid strategy on a hemodynamic response and the formation of pulmonary edema in an animal model of PARDS. Sixteen mechanically ventilated lambs (2-6 wk) received oleic acid infusion to induce PARDS and were randomized to a restrictive or liberal fluid strategy during a 6-h period of mechanical ventilation. Transpulmonary thermodilution determined extravascular lung water (EVLW) and cardiac output (CO). Postmortem lung wet-to-dry weight ratios were obtained by gravimetry. Restricting fluids significantly reduced fluid intake but increased the use of vasopressors among animals with PARDS. Arterial blood pressure was similar between groups, yet CO declined significantly in animals receiving restrictive fluids (P = 0.005). There was no difference in EVLW over time (P = 0.111) and lung wet-to-dry weight ratio [6.1, interquartile range (IQR) = 6.0-7.3 vs. 7.1, IQR = 6.6-9.4, restrictive vs. liberal, P = 0.725] between fluid strategies. Both fluid strategies stabilized blood pressure in this model, yet early fluid restriction abated CO. Early fluid restriction did not limit the formation of pulmonary edema; therefore, this study suggests that in the early phase of PARDS, a restrictive fluid strategy is not beneficial in terms of immediate cardiopulmonary effects.

Association Between Hyponatremia and Maintenance Intravenous Solutions in Critically Ill Children: A Retrospective Observational Study

Objetive: We sought to determine the association between maintenance intravenous solutions and the presence of hyponatremia in children in pediatric intensive care (PICU). Materials and Methods: An analytical observational study in children hospitalized in the PICU between January 2015 and December 2018. Patients who received maintenance fluids within the first 48 h after admission and who had at least two serum sodium levels drawn during this time were included. Measurements and Main Results: A total of 1,668 patients were admitted to the PICU during the study period, 503 of whom met the inclusion criteria. The median age was 24 months (IQR 8-96) and 50.9% were female. Altogether, 24.1% of the children developed hyponatremia; it was more frequent in those who received hypotonic solutions (63 vs. 37%; OR 1.41 95% CI 0.92, 2.15 p = 0.106), who also had a longer hospital stay (20 vs. 14 days, difference in means 8 days, 95% CI 2.67, 13.3, p = 0.001). Children who received loop diuretics and those who were post-operative had a greater risk of developing hyponatremia if they received hypotonic solutions (aOR 2.1 95% CI 1.41, 3.0, p = 0.000). Those with balanced isotonic solutions had a lower risk of developing hyponatremia (aOR 0.59 95% CI 0.35, 0.99, p = 0.004) and hyperchloremia (aOR 0.51 95% CI 0.34, 0.77, p = 0.000), adjusted for disease severity. A greater risk of death was found in the group with severe hyponatremia <130 mEq/L (aOR 9.75 95% CI 1.64-58.15; p = 0.01). Conclusions: Hyponatremia associated with the use of hypotonic maintenance solutions occurs in one out of four children in intensive care. The use of these solutions is associated with a longer hospital stay, and the main risk groups are post-operative patients and those who receive loop diuretics. Clinical studies are needed to determine which maintenance solutions have the greatest efficacy and safety in critically ill children.