The Impact of Fluid Overload on Outcomes in Children Treated With Extracorporeal Membrane Oxygenation: A Multicenter Retrospective Cohort Study

Kidney replacement therapy during extracorporeal membrane oxygenation: pathophysiology, technical considerations, and outcomes

The use of extracorporeal membrane oxygenation has been increasing over time, in part due to the COVID-19 pandemic. Whilst lifesaving, complications that must be managed are also associated with its use. AKI and fluid overload are complications of concern due to their associations with poor outcomes, and ability to be managed by additional interventions such as the use of kidney replacement therapy. Various modalities, timings, and types of kidney replacement therapy are currently being used and outcomes regarding its concurrent use with extracorporeal membranous oxygenation across centers may be mixed. In this review, we discuss the pathophysiology of AKI, methods, modalities and impact of concurrent extracorporeal membrane oxygenation and kidney replacement therapy.

A Standardized Approach to Reduce Fluid Overload in Critically Ill Children

Introduction

Fluid overload, the pathologic state of positive fluid balance, is common in the pediatric intensive care unit (PICU) and is independently associated with poor outcomes. Quality improvement-based processes to measure and assess fluid balance in critically ill children are lacking.

Methods

The primary aim was to develop and implement a fluid management strategy that includes the standardized measurement and assessment of fluid balance, which is adhered to in at least 50% of all PICU patients. The 4 components of the strategy include (1) creating a fluid balance dashboard that tracks percent cumulative fluid balance over time, (2) documentation of daily weights, (3) fluid balance reporting and discussion incorporated into standardized rounds, and (4) active total intravenous (IV) fluid order.

Results

We reviewed 280 patient encounters between May 2023 and April 2024 and achieved the primary aim of at least 50% compliance with the fluid management strategy and maintained this success over time. Achieving the primary aim coincides with implementing daily weights and total IV fluid orders into PICU admission order sets.

Conclusions

In this quality improvement project, we develop, implement, and maintain compliance with a fluid management strategy. Future work will involve daily utilization of the fluid balance dashboard and monitoring compliance with total IV fluid orders. Implementing a quality improvement-based fluid management strategy may lead to improved awareness of the fluid status of patients and the prescription of fluid therapy to mitigate the harmful effects of fluid overload.

Artificial Placenta and Artificial Womb Technologies for Lung and Kidney Failure: A Holistic Perspective

Preterm birth remains the leading cause of mortality among neonates. Despite improvements in neonatal intensive care over the years, current treatments for lung and kidney failure are highly invasive, associated with lifelong disability, and limit family integration. Artificial womb and artificial placenta technologies offer a promising alternative by providing more tailored and less invasive neonatal care. Although these technologies share some similarities, artificial womb and artificial placenta technologies differ significantly in terms of treatment initiation, treatment environment, and the potential to support family-centered care. Moreover, even though acute kidney injury is common in neonatal extracorporeal membrane oxygenation (ECMO) patients, current artificial placenta and artificial womb devices lack renal support functionality. Most artificial womb and artificial placenta studies focus on the technical feasibility of these technologies based on in-vivo animal tests. However, translation toward envisioned use of these devices in preterm neonates remains mostly underexposed. A comprehensive stakeholder analysis, including parents and caregivers, is critical to the development of socially acceptable artificial placenta and artificial womb systems. This state-of-the-art review provides an overview of conventional neonatal lung and kidney treatments, delineates the differences between artificial womb and placenta technologies, and addresses the technological and ethical challenges in advancing these technologies toward potential clinical implementation.

Efficacy and safety of extracorporeal membrane oxygenation combined with continuous renal replacement therapy in the management of pediatric acute respiratory distress syndrome

Background

The efficacy and safety of combining extracorporeal membrane oxygenation with continuous renal replacement therapy remain controversial. This study aimed to evaluate the efficacy and safety of extracorporeal membrane oxygenation combined with continuous renal replacement therapy in the treatment of pediatric acute respiratory distress syndrome.

Methods

This retrospective study, conducted at Hunan Children's Hospital between January 2019 and December 2023, included 30 pediatric patients with acute respiratory distress syndrome who underwent extracorporeal membrane oxygenation treatment. The patients were divided into two groups based on whether continuous renal replacement therapy was used during treatment: 21 in the extracorporeal membrane oxygenation with continuous renal replacement therapy group and nine in the extracorporeal membrane oxygenation-only group. The groups were compared using t-test or Wilcoxon rank-sum test.

Results

This study included 19 (63.3%) male and 11 (36.7%) female patients (mean age: 63.33 ± 54.41 months). The ratios of arterial partial pressure of oxygen to fraction of inspired oxygen before and at withdrawal of extracorporeal membrane oxygenation were 58.50 (40.75-70.31) and 257.00 (113.25-358.33) mmHg, respectively (P < 0.05). In the extracorporeal membrane oxygenation with continuous renal replacement therapy group, 21 patients (70.0%) underwent continuous renal replacement therapy, including those with acute renal injury (n = 5), fluid overload (n = 13), hyperkalemia (n = 3), and removal of inflammatory mediators (n = 3), and improvement was observed.

Conclusions

The combination of extracorporeal membrane oxygenation and continuous renal replacement therapy provides safe and effective respiratory support for pediatric patients with severe acute respiratory distress syndrome and enables effective fluid-balance management, removal of inflammatory factors, and maintenance of electrolyte equilibrium.

Concurrent use of continuous kidney replacement therapy during extracorporeal membrane oxygenation: what pediatric nephrologists need to know-PCRRT-ICONIC practice points

Extracorporeal membrane oxygenation (ECMO) provides temporary cardiorespiratory support for neonatal, pediatric, and adult patients when traditional management has failed. This lifesaving therapy has intrinsic risks, including the development of a robust inflammatory response, acute kidney injury (AKI), fluid overload (FO), and blood loss via consumption and coagulopathy. Continuous kidney replacement therapy (CKRT) has been proposed to reduce these side effects by mitigating the host inflammatory response and controlling FO, improving outcomes in patients requiring ECMO. The Pediatric Continuous Renal Replacement Therapy (PCRRT) Workgroup and the International Collaboration of Nephrologists and Intensivists for Critical Care Children (ICONIC) met to highlight current practice standards for ECMO use within the pediatric population. This review discusses ECMO modalities, the pathophysiology of inflammation during an ECMO run, its adverse effects, various anticoagulation strategies, and the technical aspects and outcomes of implementing CKRT during ECMO in neonatal and pediatric populations. Consensus practice points and guidelines are summarized. ECMO should be utilized in patients with severe acute respiratory failure despite the use of conventional treatment modalities. The Extracorporeal Life Support Organization (ELSO) offers guidelines for ECMO initiation and management while maintaining a clinical registry of over 195,000 patients to assess outcomes and complications. Monitoring and preventing fluid overload during ECMO and CKRT are imperative to reduce mortality risk. Clinical evidence, resources, and experience of the nephrologist and healthcare team should guide the selection of ECMO circuit.

Fluid deresuscitation in critically ill children: comparing perspectives of intensivists and nephrologists

Introduction

Fluid accumulation, presently defined as a pathologic state of overhydration/volume overload associated with clinical impact, is common and associated with worse outcomes. At times, deresuscitation, the active removal of fluid via diuretics or ultrafiltration, is necessary. There is no consensus regarding deresuscitation in children admitted to the pediatric intensive care unit. Little is known regarding perceptions and practices among pediatric intensivists and nephrologists regarding fluid provision and deresuscitation.

Methods

Cross-sectional electronic survey of pediatric nephrologists and intensivists from academic societies in the United States designed to better understand fluid management between disciplines. A clinical vignette was used to characterize the perceptions of optimal timing and method of deresuscitation initiation at four timepoints that correspond to different stages of shock.

Results

In total, 179 respondents (140 intensivists, 39 nephrologists) completed the survey. Most 75.4% (135/179) providers believe discussing fluid balance and initiating fluid deresuscitation in pediatric intensive care unit (PICU) patients is "very important". The first clinical vignette time point (corresponding to resuscitation phase of early shock) had the most dissimilarity between intensivists and nephrologists (p = 0.01) with regards to initiation of deresuscitation. However, providers demonstrated increasing agreement in their responses to initiate deresuscitation as the clinical vignette progressed. Compared to intensivists, nephrologists were more likely to choose "dialysis or ultrafiltration" as a deresuscitation method during the optimization [10.3 vs. 2.9% (p = 0.07)], stabilization [18.0% vs. 3.6% (p < 0.01)], and evacuation [48.7% vs. 23.6% (p < 0.01)] phases of shock. Conversely, intensivists were more likely to utilize scheduled diuretics than nephrologists [47.1% vs. 28.2% (p = 0.04)] later on in the patient course.

Discussion

Most physicians believe that discussing fluid balance and deresuscitation is important. Nevertheless, when to initiate deresuscitation and how to accomplish it differed between nephrologist and intensivists. Widely understood and operationalizable definitions, further research, and eventually evidence-based guidelines are needed to help guide care.

Physiologically Based Pharmacokinetic Modelling in Critically Ill Children Receiving Anakinra While on Extracorporeal Life Support

BACKGROUND AND OBJECTIVE

Because of the pathophysiological changes associated with critical illness and the use of extracorporeal life support (ECLS) such as continuous renal replacement therapy (CRRT) and extracorporeal membrane oxygenation (ECMO), the pharmacokinetics of drugs are often altered. The objective of this study was to develop a physiologically based pharmacokinetic (PBPK) model for anakinra in children that accounts for the physiological changes associated with critical illness and ECLS technology to guide appropriate pharmacotherapy.

METHODS

A PBPK model for anakinra was first developed in healthy individuals prior to extrapolating to critically ill children receiving ECLS. To account for the impact of anakinra clearance by the dialysis circuit, a CRRT compartment was added to the pediatric PBPK model and parameterized using data from a previously published ex-vivo study. Additionally, an ECMO compartment was added to the whole-body structure to create the final anakinra ECLS-PBPK model. The final model structure was validated by comparing predicted concentrations with observed patient data. Due to limited information in guiding anakinra dosing in this population, in-silico dose simulations were conducted to provide baseline recommendations.

RESULTS

By accounting for changes in physiology and the addition of ECLS compartments, the final ECLS-PBPK model predicted the observed plasma concentrations in an adolescent receiving subcutaneous anakinra. Furthermore, dosing simulations suggest that anakinra exposure in adolescents receiving ECLS is similar to that in healthy counterparts.

CONCLUSION

The anakinra ECLS-PBPK model developed in this study is the first to predict plasma concentrations in a population receiving simultaneous CRRT and ECMO. Dosing simulations provided may be used to inform anakinra use in critically ill children and guide future clinical trial planning.

Timing of Kidney Replacement Therapy Initiation and Survival During Pediatric Extracorporeal Membrane Oxygenation: An Extracorporeal Life Support Organization Registry Study

To characterize kidney replacement therapy (KRT) and pediatric extracorporeal membrane oxygenation (ECMO) outcomes and to identify the optimal timing of KRT initiation during ECMO associated with increased survival. Observational retrospective cohort study using the Extracorporeal Life Support Organization Registry database in children (0-18 yo) on ECMO from January 1, 2016, to December 31, 2020. Of the 14,318 ECMO runs analyzed, 26% of patients received KRT during ECMO. Patients requiring KRT before ECMO had increased mortality to ECMO decannulation (29% vs. 17%, OR 1.97, P < 0.001) and to hospital discharge (58% vs. 39%, OR 2.16, P < 0.001). Patients requiring KRT during ECMO had an increased mortality to ECMO decannulation (25% vs. 15%, OR 1.85, P < 0.001) and to hospital discharge (56% vs. 34%, OR 2.47, P < 0.001). Multivariable logistic regression demonstrated that the need for KRT during ECMO was an independent predictor for mortality to ECMO decannulation (OR 1.49, P < 0.001) and to hospital discharge (OR 2.02, P < 0.001). Patients initiated on KRT between 24 and 72 hours after cannulation were more likely to survive to ECMO decannulation and showed a trend towards survival to hospital discharge as compared to those initiated before 24 hours and after 72 hours.

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).

Neonatal Extracorporeal Membrane Oxygenation: Associations between Continuous Renal Replacement Therapy, Thrombocytopenia, and Outcomes

INTRODUCTION

The incidence of thrombocytopenia in neonates receiving extracorporeal membrane oxygenation (ECMO) with and without concurrent continuous renal replacement therapy (CRRT) and associated complications have not been well described. The primary aims of the current study were to (1) characterize thrombocytopenia in neonates receiving ECMO (including those treated concurrently with CRRT) and (2) evaluate risk factors (including CRRT utilization) associated with severe thrombocytopenia. In a planned exploratory secondary aim, we explored the association of severe thrombocytopenia with outcomes in neonates receiving ECMO.

METHODS

We conducted a retrospective single-center chart review of neonates who received ECMO 07/01/14-03/01/20 and evaluated associations between CRRT, severe thrombocytopenia (platelet count <50,000/mm3), and outcomes (ECMO duration, length of stay, and survival).

RESULTS

Fifty-two neonates received ECMO; 35 (67%) received concurrent CRRT. Severe thrombocytopenia occurred in 27 (52%) neonates overall and in 21 (60%) neonates who received concurrent CRRT. Underlying diagnosis, ECMO mode, care unit, and moderate/severe hemolysis differed between those who did and did not receive CRRT. CRRT receivers experienced shorter hospital stays than CRRT non-receivers, but ECMO duration, length of intensive care unit (ICU) stay, and survival did not differ between groups. CRRT receipt was associated with severe thrombocytopenia. Exploratory classification and regression tree (CART) analysis suggests CRRT use, birthweight, and ICU location are all predictors of interest for severe thrombocytopenia.

CONCLUSIONS

In our cohort, CRRT use during ECMO was associated with severe thrombocytopenia, and patients who received ECMO with CRRT experienced shorter hospital stays than those who did not receive CRRT. Exploratory CART analysis suggests CRRT use, birthweight, and ICU location are all predictors for severe thrombocytopenia and warrant further investigations in larger studies.

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.

A Systematic Bibliometric Analysis of High-Impact Articles in Critical Care Nephrology

INTRODUCTION

Critical care nephrology is a subspecialty that merges critical care and nephrology in response to shared pathobiology, clinical care, and technological innovations. To date, there has been no description of the highest impact articles. Accordingly, we systematically identified high impact articles in critical care nephrology.

METHODS

This was a bibliometric analysis. The search was developed by a research librarian. Web of Science was searched for articles published between January 1, 2000 and December 31, 2020. Articles required a minimum of 30 citations, publication in English language, and reporting of primary (or secondary) original data. Articles were screened by two reviewers for eligibility and further adjudicated by three experts. The "Top 100" articles were hierarchically ranked by adjudication, citations in the 2 years following publication and journal impact factor (IF). For each article, we extracted detailed bibliometric data. Risk of bias was assessed for randomized trials by the Cochrane Risk of Bias tool. Analyses were descriptive.

RESULTS

The search yielded 2,805 articles. Following initial screening, 307 articles were selected for full review and adjudication. The Top 100 articles were published across 20 journals (median [IQR] IF 10.6 [8.9-56.3]), 38% were published in the 5 years ending in 2020 and 62% were open access. The agreement between adjudicators was excellent (intraclass correlation, 0.96; 95% CI, 0.84-0.99). Of the Top 100, 44% were randomized trials, 35% were observational, 14% were systematic reviews, 6% were nonrandomized interventional studies and one article was a consensus document. The risk of bias among randomized trials was low. Common subgroup themes were RRT (42%), AKI (30%), fluids/resuscitation (14%), pediatrics (10%), interventions (8%), and perioperative care (6%). The citations for the Top 100 articles were 175 (95-393) and 9 were cited >1,000 times.

CONCLUSION

Critical care nephrology has matured as an important subspecialty of critical care and nephrology. These high impact papers have focused largely on original studies, mostly clinical trials, within a few core themes. This list can be leveraged for curricula development, to stimulate research, and for quality assurance.

Optimizing Outcomes in Extracorporeal Membrane Oxygenation Postcardiotomy in Pediatric Population

Extracorporeal membrane oxygenation (ECMO) is a rapidly emerging advanced life support technique used in cardiorespiratory failure refractory to other treatments. There has been an influx in the number of studies relating to ECMO in recent years, as the technique becomes more popular. However, there are still significant gaps in the literature including complications and their impacts and methods to predict their development. This review evaluates the available literature on the complications of ECMO postcardiotomy in the pediatric population. Areas explored include renal, cardiovascular, hematological, infection, neurological, and hepatic complications. Incidence, risk factors and potential predictors, and scoring systems for the development of these complications have been evaluated.

Early acute kidney injury and transition to renal replacement therapy in critically ill patients with SARS-CoV-2 requiring veno-venous extracorporeal membrane oxygenation

BACKGROUND

Critically ill patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) requiring veno-venous extracorporeal membrane oxygenation (vv-ECMO) are at risk for acute kidney injury (AKI). Currently, the incidence of AKI and progression to kidney replacement therapy (RRT) in critically ill patients with vv-ECMO for severe COVID-19 and implications on outcome are still unclear.

METHODS

Retrospective analysis at the University Medical Center Hamburg-Eppendorf (Germany) between March 1st, 2020 and July 31st, 2021. Demographics, clinical parameters, AKI, type of organ support, length of ICU stay, mortality and severity scores were assessed.

RESULTS

Ninety-one critically ill patients with SARS-CoV-2 requiring ECMO were included. The median age of the study population was 57 (IQR 49-64) years and 67% (n = 61) were male. The median SAPS II and SOFA Score on admission were 40 (34-46) and 12 (10-14) points, respectively. We observed that 45% (n = 41) developed early-AKI, 38% (n = 35) late-AKI and 16% (n = 15) no AKI during the ICU stay. Overall, 70% (n = 64) of patients required RRT during the ICU stay, 93% with early-AKI and 74% with late-AKI. Risk factors for early-AKI were younger age (OR 0.94, 95% CI 0.90-0.99, p = 0.02) and SAPS II (OR 1.12, 95% CI 1.06-1.19, p < 0.001). Patients with and without RRT were comparable regarding baseline characteristics. SAPS II (41 vs. 37 points, p < 0.05) and SOFA score (13 vs. 12 points, p < 0.05) on admission were significantly higher in patients receiving RRT. The median duration of ICU (36 vs. 28 days, p = 0.27) stay was longer in patients with RRT. An ICU mortality rate in patients with RRT in 69% (n = 44) and in patients without RRT of 56% (n = 27) was observed (p = 0.23).

CONCLUSION

Critically ill patients with severe SARS-CoV-2 related ARDS requiring vv-ECMO are at high risk of early acute kidney injury. Early-AKI is associated with age and severity of illness, and presents with high need for RRT. Mortality in patients with RRT was comparable to patients without RRT.

Early postoperative weight-based fluid overload is associated with worse outcomes after neonatal cardiac surgery

OBJECTIVES

Evaluate the association of postoperative day (POD) 2 weight-based fluid balance (FB-W) > 10% with outcomes after neonatal cardiac surgery.

METHODS

Retrospective cohort study of 22 hospitals in the NEonatal and Pediatric Heart and Renal Outcomes Network (NEPHRON) registry from September 2015 to January 2018. Of 2240 eligible patients, 997 neonates (cardiopulmonary bypass (CPB) n = 658, non-CPB n = 339) were weighed on POD2 and included.

RESULTS

Forty-five percent (n = 444) of patients had FB-W > 10%. Patients with POD2 FB-W > 10% had higher acuity of illness and worse outcomes. Hospital mortality was 2.8% (n = 28) and not independently associated with POD2 FB-W > 10% (OR 1.04; 95% CI 0.29-3.68). POD2 FB-W > 10% was associated with all utilization outcomes, including duration of mechanical ventilation (multiplicative rate of 1.19; 95% CI 1.04-1.36), respiratory support (1.28; 95% CI 1.07-1.54), inotropic support (1.38; 95% CI 1.10-1.73), and postoperative hospital length of stay (LOS 1.15; 95% CI 1.03-1.27). In secondary analyses, POD2 FB-W as a continuous variable demonstrated association with prolonged durations of mechanical ventilation (OR 1.04; 95% CI 1.02-1.06], respiratory support (1.03; 95% CI 1.01-1.05), inotropic support (1.03; 95% CI 1.00-1.05), and postoperative hospital LOS (1.02; 95% CI 1.00-1.04). POD2 intake-output based fluid balance (FB-IO) was not associated with any outcome.

CONCLUSIONS

POD2 weight-based fluid balance > 10% occurs frequently after neonatal cardiac surgery and is associated with longer cardiorespiratory support and postoperative hospital LOS. However, POD2 FB-IO was not associated with clinical outcomes. Mitigating early postoperative fluid accumulation may improve outcomes but requires safely weighing neonates in the early postoperative period. A higher resolution version of the Graphical abstract is available as Supplementary information.

Fluid Management in Veno-Arterial Extracorporeal Membrane Oxygenation Therapy-Analysis of an Experimental Pig Model

(1) Background: Fluid resuscitation is a necessary part of therapeutic measures to maintain sufficient hemodynamics in extracorporeal membrane oxygenation (ECMO) circulation. In a post-hoc analysis, we aimed to investigate the impact of increased volume therapy in veno-arterial ECMO circulation on renal function and organ edema in a large animal model. (2) Methods: ECMO therapy was performed in 12 female pigs (Deutsche Landrasse × Pietrain) for 10 h with subsequent euthanasia. Applicable volume, in regard to the necessary maintenance of hemodynamics, was divided into moderate and extensive volume therapy (MVT/EVT) due to the double quantity of calculated physiologic urine output for the planned study period. Respiratory and hemodynamic data were measured continuously. Additionally, renal function and organ edema were assessed by blood and tissue samples. (3) Results: Four pigs received MVT, and eight pigs received EVT. After 10 h of ECMO circulation, no major differences were seen between the groups in regard to hemodynamic and respiratory data. The relative change in creatinine after 10 h of ECMO support was significantly higher in EVT (1.3 ± 0.3 MVT vs. 1.8 ± 0.5 EVT; p = 0.033). No major differences were evident for lung, heart, liver, and kidney samples in regard to organ edema in comparison of EVT and MVT. Bowel tissue showed a higher percentage of edema in EVT compared to MVT (77 ± 2% MVT vs. 80 ± 3% EVT; p = 0.049). (4) Conclusions: The presented data suggest potential deterioration of renal function and intestinal mucosa function by an increase in tissue edema due to volume overload in ECMO therapy.

The numerical value of fluid balance to predict survival in neonates requiring extracorporeal membrane oxygenation

BACKGROUND

The aim of this study was to understand numerical variation of fluid balance in neonates requiring extracorporeal membrane oxygenation (ECMO) and to assess the relationship between hourly fluid balance and mortality.

METHODS

This is a prospective cohort study. All neonates supported by ECMO were enrolled from October 2011 to September 2017. All of the enrolled neonates were divided into survival group and non- survival group. The numerical value of fluid balance of the enrolled neonates were recorded at 6 hours, 12 hours, 24 hours, 36 hours and 48 hours after initiation of ECMO respectively. The differences between the two groups were compared. The numerical value of fluid balance predict survival by the receiver operating characteristic (ROC) curve.

RESULTS

Forty-eight neonates were enrolled, in which 35 cases were survival and the survival rate was 72.9%. The numerical value of fluid balance in the survival group were lower than that in the non-survival group at 6 hours, 12 hours, 24 hours, 36 hours and 48 hours after ECMO(all P<0.05). The area under ROC curve at 6h, 12h, 24h, 36h and 48h after initiation of ECMO was 0.835, 0.900, 0.839, 0.909 and 0.974 respectively. There were statistically significant in the numerical value of fluid balance predicting survival (all P<0.05) and a high sensitivity, specificity and positive predictive value at the each time point.

CONCLUSIONS

The negative hourly fluid balance were associated with decreased mortality, and the lower the numerical value of fluid balance in neonates requiring ECMO, the higher the survival rate.

Advances in pulmonary management and weaning from ECLS

ECMO for neonatal and pediatric respiratory failure provides gas exchange to allow lung recovery from reversible pulmonary ailments. This is a comprehensive discussion on the various strategies and advances utilized by pediatric ECLS specialists today. ECMO patients require continual monitoring, serial gasses and radiographs, near-infrared spectroscopy (NIRS - to monitor oxygen delivery to regional tissue beds), and more quality ECLS directed care. As the foundation to lung recovery, good EMCO closely monitors ECLS flow rates, sweep gasses, and membrane lung function. Mixed venous oxygen saturation (Sv02) greater than 65% indicates good oxygen delivery and sweep gas adjustments maintain PaCO2 of 40-45 mm Hg. Lung recovery ventilatory settings do not fully rest the lungs but maintain normal or nontoxic pressure and oxygen levels. Neonatal recovery settings are PIP (cm H20) of 15-20, PEEP of 5-10, ventilator rate of 12-20 and an inspiratory time of 0.5-1 s, and FiO2 of 0.3-0.5. Pediatric recovery settings are PIP (cm H20) < 25, PEEP of 5-15, ventilator rate of 10-20 and an inspiratory time of 0.8-1 s, and FiO2 of <0.5. Some studies demonstrate a higher recovery PEEP level decreases duration of ECMO, but do not demonstrate a mortality difference. Multiple adjunctive therapies such as surfactant, routine pulmonary clearance and respiratory physiotherapy, iNO, prone positioning, bronchoscopy, POCUS, CT imaging, and extubation or "awake ECLS" can significantly affect pulmonary recovery. Patience is necessary as lung recovery may take weeks or even months on the nontoxic settings. On these settings, dynamic recovery will be revealed by improvement in tidal volume, minute ventilation and radiographic pulmonary aeration, prompting discussion about weaning. When this pulmonary compliance recovery becomes evident, decreasing ECLS flow while also decreasing circuit FiO2 and/or sweep gas are common components to ECMO weaning strategies.

Managing the kidney - The role of continuous renal replacement therapy in neonatal and pediatric ECMO

Extracorporeal membrane oxygenation (ECMO) represents a lifesaving therapy utilized in in the most critically ill neonates and children with reversible cardiopulmonary failure. As a result of the severity of their critical illness these patients are among the highest risk populations for developing acute kidney injury (AKI) and disorders of fluid balance including the pathologic state of fluid overload (FO). In multiple studies AKI has been shown to occur commonly in 60-80% children treated with ECMO and is associated with adverse outcomes. In early studies evaluating ECMO in neonatal respiratory populations, the importance of fluid balance and the development of FO was recognized as an important contributor to adverse outcomes. Multiple single center studies and multicenter work have confirmed that FO occurs commonly across ECMO populations and is consistently associated with adverse outcomes. As a result of the high rates of AKI and the high rates of FO, continuous renal replacement therapy (CRRT) is increasingly utilized in neonatal and pediatric ECMO. In this state-of-the-art review, we cover the definitions, pathophysiology, incidence, and impact of AKI and FO in neonates and children supported with ECMO and summarize and appraise the evidence regarding the use of CRRT concurrently with ECMO. This review will cover the appropriate timing of this initiation, the options for providing CRRT with ECMO, overview of CRRT prescription, and the long-term implications of kidney support therapy in this population.

Clinical Predictive Tool for Pediatric Cardiac Patients on Extracorporeal Membrane Oxygenation Therapy and Ultrafiltration

Fluid overload is common among pediatric cardiac patients receiving extracorporeal membrane oxygenation (ECMO) and is often treated with in-line ultrafiltration (UF) or continuous renal replacement therapy (CRRT). We assessed whether CRRT was associated with poor outcomes versus UF alone. Additionally, we identified characteristics associated with progression from UF to CRRT. Retrospective chart review of 131 patients age ≤18 years treated with ECMO at a single quaternary center. Data were collected to compare patient demographics, characteristics, and outcomes. A receiver operator curve (ROC) was used to create a tool predictive of the need for CRRT at the time of UF initiation. Patients who required CRRT had a higher creatinine and blood urea nitrogen at time of UF initiation ( p = 0.03 and p < 0.01), longer total ECMO duration ( p < 0.01), lower renal recovery incidence ( p = 0.02), and higher mortality ( p ≤ 0.01). Using ROC analysis, presence of ≤3 of 7 risk variables had a positive predictive value of 87.5% and negative predictive value of 50.0% for use of UF alone (area under the curve 0.801; 95% CI: 0.638-0.965, p = 0.002). Pediatric cardiac patients treated with ECMO and UF who require CRRT demonstrate worse outcomes versus UF alone. A novel clinical tool may assist in stratifying patients at UF initiation.

Impact of the Magnitude and Timing of Fluid Overload on Outcomes in Critically Ill Children: A Report From the Multicenter International Assessment of Worldwide Acute Kidney Injury, Renal Angina, and Epidemiology (AWARE) Study

OBJECTIVES

With the recognition that fluid overload (FO) has a detrimental impact on critically ill children, the critical care nephrology community has focused on identifying clinically meaningful targets for intervention. The current study aims to evaluate the epidemiology and outcomes associated with FO in an international multicenter cohort of critically ill children. The current study also aims to evaluate the association of FO at predetermined clinically relevant thresholds and time points (FO ≥ 5% and FO ≥ 10% at the end of ICU days 1 and 2) with outcomes.

DESIGN

Prospective cohort study.

SETTING

Multicenter, international collaborative of 32 pediatric ICUs.

PATIENTS

A total of 5,079 children and young adults admitted consecutively to pediatric ICUs as part of the Assessment of the Worldwide Acute Kidney Injury, Renal Angina and Epidemiology Study.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The FO thresholds at the time points of interest occurred commonly in the cohort (FO ≥ 5%Day1 in 38.1% [ n = 1753], FO ≥ 10%Day1 in 11.7% [ n = 537], FO ≥ 5%Day2 in 53.3% [ n = 1,539], FO ≥ 10%Day2 in 25.1% [ n = 724]). On Day1, multivariable modeling demonstrated that FO ≥ 5% was associated with fewer ICU-free days, and FO ≥ 10% was associated with higher mortality and fewer ICU and ventilator-free days. On multivariable modeling, FO-peak, Day2 FO ≥ 5%, and Day2 FO ≥ 10% were associated with higher mortality and fewer ICU and ventilator-free days.

CONCLUSIONS

This study found that mild-to-moderate FO as early as at the end of ICU Day1 is associated with adverse outcomes. The current study fills an important void in the literature by identifying critical combinations of FO timing and quantity associated with adverse outcomes (FO ≥ 5%Day1, FO ≥10%Day1, FO ≥ 5%Day2, and FO ≥ 10%Day2). Those novel findings will help guide the development of interventional strategies and trials targeting the treatment and prevention of clinically relevant FO.

Synergistic association of fluid overload and acute kidney injury on outcomes in pediatric cardiac ECMO: a retrospective analysis of the KIDMO database

BACKGROUND

Acute kidney injury (AKI) and fluid overload (FO) are associated with poor outcomes in children receiving extracorporeal membrane oxygenation (ECMO). Our objective is to evaluate the impact of AKI and FO on pediatric patients receiving ECMO for cardiac pathology.

METHODS

We performed a secondary analysis of the six-center Kidney Interventions During Extracorporeal Membrane Oxygenation (KIDMO) database, including only children who underwent ECMO for cardiac pathology. AKI was defined using Kidney Disease: Improving Global Outcomes (KDIGO) creatinine criteria. FO was defined as < 10% (FO-) vs. ≥ 10% (FO +) and was evaluated at ECMO initiation, peak during ECMO, and ECMO discontinuation. Primary outcomes were mortality and length of stay (LOS).

RESULTS

Data from 191 patients were included. Non-survivors (56%) were more likely to be FO + than survivors at peak ECMO fluid status and ECMO discontinuation. There was a significant interaction between AKI and FO. In the presence of AKI, the adjusted odds of mortality for FO + was 4.79 times greater than FO- (95% CI: 1.52-15.12, p = 0.01). In the presence of FO + , the adjusted odds of mortality for AKI + was 2.7 times higher than AKI- [95%CI: 1.10-6.60; p = 0.03]. Peak FO + was associated with a 55% adjusted relative increase in LOS [95%CI: 1.07-2.26, p = 0.02].

CONCLUSIONS

The association of peak FO + with mortality is present only in the presence of AKI + . Similarly, AKI + is associated with mortality only in the presence of peak FO + . FO + was associated with LOS. Studies targeting fluid management have the potential to improve LOS and mortality outcomes. A higher resolution version of the Graphical abstract is available as Supplementary information.

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.

Effect of a standardized fluid management algorithm on acute kidney injury and mortality in pediatric patients on extracorporeal support

Acute kidney injury (AKI), fluid overload (FO), and mortality are common in pediatric patients supported by extracorporeal membrane oxygenation (ECMO). The aim of this study is to evaluate if using a fluid management algorithm reduced AKI and mortality in children supported by ECMO. We performed a retrospective study of pediatric patients aged birth to 25 years requiring ECMO at a quaternary level children's hospital from 2007 to 2019 In October 2017, a fluid management algorithm was implemented for protocolized fluid removal after deriving a daily fluid goal using a combination of diuretics and ultrafiltration. Daily algorithm compliance was defined as ≥ 12 h on the algorithm each day. The primary and secondary outcomes were AKI and mortality, respectively, and were assessed in the entire cohort and the sub-analysis of children from the era in which the algorithm was implemented. Two hundred and ninety-nine (median age 5.3 months; IQR: 0.2, 62.3; 45% male) children required ECMO (venoarterial in 85%). The fluid algorithm was applied in 74 patients. The overall AKI rate during ECMO was 38% (26% severe-stage 2/3). Both AKI incidence and mortality were significantly lower in patients managed on the algorithm (p = 0.02 and p = 0.05). After adjusting for confounders, utilization of the algorithm was associated with lower odds of AKI (aOR: 0.40, 95%CI: 0.21, 0.76; p = 0.005) but was not associated with a reduction in mortality. In the sub-analysis, algorithm compliance of 80-100% was associated with a 54% reduction in mortality (ref: < 60% compliant; aOR:0.46, 95%CI:0.22-1.00; p = 0.05).  Conclusion: Among the entire cohort, the use of a fluid management algorithm reduced the odds of AKI. Better compliance on the algorithm was associated with lower mortality. Multicenter studies that implement systematic fluid removal may represent an opportunity for improving ECMO-related outcomes. What is Known: • Acute kidney injury and fluid overload are associated with morbidity and mortality in children supported by extracorporeal membrane oxygenation. What is New: • A systematic and protocolized approach to fluid removal in children supported by extracorporeal membrane oxygenation reduces acute kidney injury incidence. • Greater adherence to a protocolized fluid removal algorithm is associated with a reduction in mortality.

Factors associated with acute kidney injury in patients undergoing extracorporeal membrane oxygenation: retrospective cohort

OBJECTIVE

To identify factors associated with acute kidney injury in patients undergoing extracorporeal membrane oxygenation.

METHOD

Retrospective cohort study conducted in an adult Intensive Care Unit with patients undergoing extracorporeal membrane oxygenation from 2012 to 2021. The research used the Kidney Disease Improving Global Outcomes as criteria for definition and classification of acute kidney injury. A multiple logistic regression model was developed to analyze the associated factors.

RESULTS

The sample was composed of 122 individuals, of these, 98 developed acute kidney injury (80.3%). In multiple regression, the associated factors found were vasopressin use, Nursing Activities Score, and glomerular filtration rate.

CONCLUSION

The use of vasopressin, the Nursing Activities Score, and the glomerular filtration rate were considered as factors related to the development of acute kidney injury in patients undergoing extracorporeal membrane oxygenation.

Perioperative extracorporeal membrane oxygenation in pediatric congenital heart disease: Chinese expert consensus

BACKGROUND

Congenital heart disease (CHD) is one of the main supportive diseases of extracorporeal membrane oxygenation in children. The management of extracorporeal membrane oxygenation (ECMO) for pediatric CHD faces more severe challenges due to the complex anatomical structure of the heart, special pathophysiology, perioperative complications and various concomitant malformations. The survival rate of ECMO for CHD was significantly lower than other classifications of diseases according to the Extracorporeal Life Support Organization database. This expert consensus aims to improve the survival rate and reduce the morbidity of this patient population by standardizing the clinical strategy.

METHODS

The editing group of this consensus gathered 11 well-known experts in pediatric cardiac surgery and ECMO field in China to develop clinical recommendations formulated on the basis of existing evidences and expert opinions.

RESULTS

The primary concern of ECMO management in the perioperative period of CHD are patient selection, cannulation strategy, pump flow/ventilator parameters/vasoactive drug dosage setting, anticoagulation management, residual lesion screening, fluid and wound management and weaning or transition strategy. Prevention and treatment of complications of bleeding, thromboembolism and brain injury are emphatically discussed here. Special conditions of ECMO management related to the cardiovascular anatomy, haemodynamics and the surgical procedures of common complex CHD should be considered.

CONCLUSIONS

The consensus could provide a reference for patient selection, management and risk identification of perioperative ECMO in children with CHD. Video abstract (MP4 104726 kb).

Neonatal fluid overload-ignorance is no longer bliss

Excessive accumulation of fluid may result in interstitial edema and multiorgan dysfunction. Over the past few decades, the detrimental impact of fluid overload has been further defined in adult and pediatric populations. Growing evidence highlights the importance of monitoring, preventing, managing, and treating fluid overload appropriately. Translating this knowledge to neonates is difficult as they have different disease pathophysiologies, and because neonatal physiology changes rapidly postnatally in many of the organ systems (i.e., skin, kidneys, and cardiovascular, pulmonary, and gastrointestinal). Thus, evaluations of the optimal targets for fluid balance need to consider the disease state as well as the gestational and postmenstrual age of the infant. Integration of what is known about neonatal fluid overload with individual alterations in physiology is imperative in clinical management. This comprehensive review will address what is known about the epidemiology and pathophysiology of neonatal fluid overload and highlight the known knowledge gaps. Finally, we provide clinical recommendations for monitoring, prevention, and treatment of fluid overload.

Update on pre-ECMO evaluation and treatment for term infants in respiratory failure

The epidemiology, diagnostic and management approach to severe hypoxemic respiratory failure in the term and near-term neonate has evolved over time, as has the need for extracorporeal membrane oxygenation (ECMO) support in this patient population. Many patients who historically would have required ECMO support now respond to less invasive therapies, with patients requiring ECMO generally representing a higher risk and more heterogenous group of underlying diagnoses. This review will highlight these changes over time and the current available evidence for the diagnosis and management of these infants, as well as the current indications and relative contraindications to ECMO support when oxygen delivery cannot meet demand with less invasive management.

Fluid Accumulation in Mechanically Ventilated, Critically Ill Children: Retrospective Cohort Study of Prevalence and Outcome

OBJECTIVES

To describe the prevalence, patterns, explanatory variables, and outcomes associated with fluid accumulation (FA) in mechanically ventilated children.

DESIGN

Retrospective cohort study.

SETTING

Tertiary PICU.

PATIENTS

Children mechanically ventilated for greater than or equal to 24 hours.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Between July 2016 and July 2021, 1,636 children met eligibility criteria. Median age was 5.5 months (interquartile range [IQR], 0.7-46.5 mo), and congenital heart disease was the most common diagnosis. Overall, by day 7 of admission, the median maximum cumulative FA, as a percentage of estimated admission weight, was 7.5% (IQR, 3.3-15.1) occurring at a median of 4 days after admission. Overall, higher FA was associated with greater duration of mechanical ventilation (MV) (mean difference, 1.17 [95% CI, 1.13-1.22]; p < 0.001]), longer intensive care length of stay (LOS) (mean difference, 1.16 [95% CI, 1.12-1.21]; p < 0.001]), longer hospital LOS (mean difference, 1.19 [95% CI, 1.13-1.26]; p < 0.001]), and increased mortality (odds ratio, 1.31 [95% CI, 1.08-1.59]; p = 0.005). However, these associations depended on the effects of children with extreme values, and there was no increase in risk up to 20% FA, overall, in children following cardiopulmonary bypass and in children in the general ICU. When excluding children with maximum FA of >10%, there was no association with duration of MV (mean difference, 0.99 [95% CI, 0.94-1.04]; p = 0.64) and intensive care or hospital LOS (mean difference, 1.01 [95% CI, 0.96-1.06]; p = 0.70 and 1.01 [95% CI, 0.95-1.08]; 0.79, respectively) but an association with reduced mortality 0.71 (95% CI, 0.53-0.97; p = 0.03).

CONCLUSIONS

In mechanically ventilated critically ill children, greater maximum FA was associated with longer duration of MV, intensive care LOS, hospital LOS, and mortality. However, these findings were driven by extreme values of FA of greater than 20%, and up to 10%, there was reduced mortality and no signal of harm.

Consensus-Based Recommendations on Priority Activities to Address Acute Kidney Injury in Children: A Modified Delphi Consensus Statement

IMPORTANCE

Increasing evidence indicates that acute kidney injury (AKI) occurs frequently in children and young adults and is associated with poor short-term and long-term outcomes. Guidance is required to focus efforts related to expansion of pediatric AKI knowledge.

OBJECTIVE

To develop expert-driven pediatric specific recommendations on needed AKI research, education, practice, and advocacy.

EVIDENCE REVIEW

At the 26th Acute Disease Quality Initiative meeting conducted in November 2021 by 47 multiprofessional international experts in general pediatrics, nephrology, and critical care, the panel focused on 6 areas: (1) epidemiology; (2) diagnostics; (3) fluid overload; (4) kidney support therapies; (5) biology, pharmacology, and nutrition; and (6) education and advocacy. An objective scientific review and distillation of literature through September 2021 was performed of (1) epidemiology, (2) risk assessment and diagnosis, (3) fluid assessment, (4) kidney support and extracorporeal therapies, (5) pathobiology, nutrition, and pharmacology, and (6) education and advocacy. Using an established modified Delphi process based on existing data, workgroups derived consensus statements with recommendations.

FINDINGS

The meeting developed 12 consensus statements and 29 research recommendations. Principal suggestions were to address gaps of knowledge by including data from varying socioeconomic groups, broadening definition of AKI phenotypes, adjudicating fluid balance by disease severity, integrating biopathology of child growth and development, and partnering with families and communities in AKI advocacy.

CONCLUSIONS AND RELEVANCE

Existing evidence across observational study supports further efforts to increase knowledge related to AKI in childhood. Significant gaps of knowledge may be addressed by focused efforts.

EvaLuation of early CRRT and beta-blocker InTervention in patients with ECMO (ELITE) trial: study protocol for a 2 × 2 partial factorial randomized controlled trial

Background

In critically ill patients requiring extracorporeal membrane oxygenation (ECMO) therapy, early initiation of continuous renal replacement therapy (CRRT) and beta-blockade of catecholamine-induced inotropic effects may improve outcomes.

Methods

A 2 × 2 partial factorial randomized controlled trial in eligible ECMO patients without a clear indication or contraindication to either intervention is centrally randomly assigned to (A) early or conventional-indicated CRRT and/or (B) beta-blocker or usual care. The primary outcome is all-cause mortality at 30 days for both arms. A total of 496 participants provides 80% power to determine a 20% risk reduction in mortality at 30 days with 5% type I error.

Discussion

This trial will help define the role of early CRRT and beta-blockade in ECMO patients. There have been 89 patients enrolled at 10 hospitals in study A and is ongoing. However, study B was stopped in August 2019 in the absence of any patients being enrolled.

Trial registration

ClinicalTrials.govNCT03549923. Registered on 8 June 2018. World Health Organization International Clinical Trials Registry Platform (WHO ICTEP) network. The Ethics Committee of Beijing Anzhen Hospital Approval ID is 2018013.

Acute Kidney Injury and Fluid Overload in Pediatric Extracorporeal Cardio-Pulmonary Resuscitation: A Multicenter Retrospective Cohort Study

Acute kidney injury (AKI) and fluid overload (FO) are common complications of extracorporeal membrane oxygenation (ECMO). The purpose of this study was to characterize AKI and FO in children receiving extracorporeal cardiopulmonary resuscitation (eCPR). We performed a multicenter retrospective study of children who received eCPR. AKI was assessed during ECMO and FO defined as <10% [FO-] vs. ≥10% [FO+] evaluated at ECMO initiation and discontinuation. A composite exposure, defined by a four-group discrete phenotypic classification [FO-/AKI-, FO-/AKI+, FO+/AKI-, FO+/AKI+] was also evaluated. Primary outcome was mortality and hospital length of stay (LOS) among survivors. 131 patients (median age 29 days (IQR:9, 242 days); 51% men and 82% with underlying cardiac disease) were included. 45.8% survived hospital discharge. FO+ at ECMO discontinuation, but not AKI was associated with mortality [aOR=2.3; 95% CI: 1.07-4.91]. LOS for FO+ patients was twice as long as FO- patients, irrespective of AKI status [(FO+/AKI+ (60 days; IQR: 49-83) vs. FO-/AKI+ (30 days, IQR: 19-48 days); P = 0.01]. FO+ at ECMO initiation and discontinuation was associated with an adjusted 66% and 50% longer length of stay respectively. Prospective studies that target timing and strategy of fluid management, including its removal in children receiving ECPR are greatly needed.

Extracorporeal Life Support Organization Guidelines for Fluid Overload, Acute Kidney Injury, and Electrolyte Management

DISCLAIMER

This guideline for extracorporeal membrane oxygenation (ECMO) fluid and electrolyte management for all patient populations is intended for educational use to build the knowledge of physicians and other health professionals in assessing the conditions and managing the treatment of patients undergoing extracorporeal life support (ECLS)/ECMO and describe what are believed to be useful and safe practice for ECLS/ECMO, but these are not necessarily consensus recommendations. The aim of clinical guidelines is to help clinicians to make informed decisions about their patients. However, adherence to a guideline does not guarantee a successful outcome. Ultimately, healthcare professionals must make their own treatment decisions about care on a case-by-case basis, after consultation with their patients, using their clinical judgment, knowledge, and expertise. These guidelines do not take the place of physicians' and other health professionals' judgment in diagnosing and treatment of particular patients. These guidelines are not intended to and should not be interpreted as setting a standard of care or be deemed inclusive of all proper methods of care nor exclusive of other methods of care reasonably directed to obtaining the same results. The ultimate judgment must be made by the physician and other health professionals and the patient in light of all the circumstances presented by the individual patient, and the known variability and biologic behavior of the clinical condition. These guidelines reflect the data at the time the guidelines were prepared; the results of subsequent studies or other information may cause revisions to the recommendations in these guidelines to be prudent to reflect new data, but Extracorporeal Life Support Organization (ELSO) is under no obligation to provide updates. In no event will ELSO be liable for any decision made or action taken in reliance upon the information provided through these guidelines.

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.

Acute Kidney Injury and Extracorporeal Membrane Oxygenation: Review on Multiple Organ Support Options

Extracorporeal membrane oxygenation (ECMO) is a temporary life support system used to assist patients with life-threatening severe cardiac and/or respiratory insufficiency. Patients requiring ECMO can be considered the sickest patients admitted to the intensive care unit (ICU). Acute kidney injury (AKI) represents a frequent complication during ECMO, affecting up to 70% of patients, with multifactorial pathophysiology and an independent risk factor for mortality. Severe AKI requiring Continuous Renal Replacement Therapy (CRRT) occurs in 20% of ECMO patients, but multiple indications and different timing may imply a significantly higher application rate in different centers. CRRT can be run in parallel to ECMO through different vascular access, or it can be conducted in series by connecting the circuits. Anticoagulation of ECMO is typically managed with systemic heparin, but several approaches can be applied for the CRRT circuit, from no anticoagulation to the addition of intra-filter heparin or regional citrate anticoagulation. The combination of CRRT and ECMO can be considered a form of multiple organ support therapy, but this approach still requires optimization in timing, set-up, anticoagulation, prescription and delivery. The aim of this report is to review the pathophysiology of AKI, the CRRT delivery, anticoagulation strategies and outcomes of patients with AKI treated with ECMO.

Systemic Hypertension in Pediatric Veno-Venous Extracorporeal Membrane Oxygenation

Systemic hypertension (HTN) is a recognized complication of veno-venous (VV) extracorporeal membrane oxygenation (ECMO) in children. We sought to determine the prevalence and associated features of HTN in a retrospective cohort of children (>1 year old) supported with VV ECMO from January 2015 to July 2019 at our institution. Patient and ECMO-related characteristics were reviewed, including intensive care unit (ICU) length of stay (LOS), ECMO duration, corticosteroids and nephrotoxic medication exposure, acute kidney injury (AKI), overall fluid balance, and transfusion data. We analyzed 23 children (43% female) with a median age of 8.5 years (interquartile range [IQR] = 4-14.5). Median ICU LOS was 26 days (IQR = 15-47) with a median ECMO duration of 288 hours (IQR = 106-378) and a mortality rate of 35%. HTN was diagnosed in 87% subjects at a median of 25 ECMO hours (IQR = 9-54) of whom 55% were hypertensive >50% of their ECMO duration. AKI and fluid overload were documented in >50% of cohort. All but two subjects received at least one nephrotoxic medication, and nearly all received corticosteroids. Our data demonstrate that HTN is present in a preponderance of children supported with VV ECMO and appears within the first 3 days of cannulation. Underlying etiology is likely multifactorial.

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.

Fluid Balance in the Critically Ill Child Section: "How Bad Is Fluid in Neonates?"

Fluid overload (FO) in neonates is understudied, and its management requires nuanced care and an understanding of the complexity of neonatal fluid dynamics. Recent studies suggest neonates are susceptible to developing FO, and neonatal fluid balance is impacted by multiple factors including functional renal immaturity in the newborn period, physiologic postnatal diuresis and weight loss, and pathologies that require fluid administration. FO also has a deleterious impact on other organ systems, particularly the lung, and appears to impact survival. However, assessing fluid balance in the postnatal period can be challenging, particularly in extremely low birth weight infants (ELBWs), given the confounding role of maternal serum creatinine (Scr), physiologic weight changes, insensible losses that can be difficult to quantify, and difficulty in obtaining accurate intake and output measurements given mixed diaper output. Although significant FO may be an indication for kidney replacement therapy (KRT) in older children and adults, KRT may not be technically feasible in the smallest infants and much remains to be learned about optimal KRT utilization in neonates. This article, though not a meta-analysis or systematic review, presents a comprehensive review of the current evidence describing the effects of FO on outcomes in neonates and highlights areas where additional research is needed.

Continuous renal replacement therapy in patients treated with extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) is a life‐saving therapy utilized for patients with severe life‐threatening cardiorespiratory failure. Patients treated with ECMO are among the most severely ill encountered in critical care and are at high‐risk of developing multiple organ dysfunction, including acute kidney injury (AKI) and fluid overload. Continuous renal replacement therapy (CRRT) is increasingly utilized inpatients on ECMO to manage AKI and treat fluid overload. The indications for renal replacement therapy for patients on ECMO are similar to those of other critically ill populations; however, there is wide practice variation in how renal supportive therapies are utilized during ECMO. For patients requiring both CRRT and ECMO, CRRT may be connected directly to the ECMO circuit, or CRRT and ECMO may be performed independently. This review will summarize current knowledge of the epidemiology of AKI, indications and timing of CRRT, delivery of CRRT, and the outcomes of patients requiring CRRT with ECMO.

Acute Kidney Injury, Fluid Overload, and Renal Replacement Therapy Differ by Underlying Diagnosis in Neonatal Extracorporeal Support and Impact Mortality Disparately

INTRODUCTION

We aimed to characterize acute kidney injury (AKI), fluid overload (FO), and renal replacement therapy (RRT) utilization by diagnostic categories and examine associations between these complications and mortality by category.

METHODS

To test our hypotheses, we conducted a retrospective multicenter, cohort study including 446 neonates (categories: 209 with cardiac disease, 114 with congenital diaphragmatic hernia [CDH], 123 with respiratory disease) requiring extracorporeal membrane oxygenation (ECMO) between January 1, 2007, and December 31, 2011.

RESULTS

AKI, FO, and RRT each varied by diagnostic category. AKI and RRT receipt were most common in those neonates with cardiac disease. Subjects with CDH had highest peak %FO (51% vs. 28% cardiac vs. 32% respiratory; p < 0.01). Hospital survival was 55% and varied by diagnostic category (45% cardiac vs. 48% CDH vs. 79% respiratory; p < 0.001). A significant interaction suggested risk of mortality differed by diagnostic category in the presence or absence of AKI. In its absence, diagnosis of CDH (vs. respiratory disease) (OR 3.04, 95% CL 1.14-8.11) independently predicted mortality. In all categories, peak %FO (OR 1.20, 95% CL 1.11-1.30) and RRT receipt (OR 2.12, 95% CL 1.20-3.73) were independently associated with mortality.

DISCUSSION/CONCLUSIONS

Physiologically distinct ECMO diagnoses warrant individualized treatment strategies given variable incidence and effects of AKI, FO, and RRT by category on mortality.

Association of Fluid Balance and Survival of Pediatric Patients Treated With Extracorporeal Membrane Oxygenation

The effect of positive fluid balance (FB) on extracorporeal membrane oxygenation (ECMO) outcomes in pediatric patients remains unknown. We sought to evaluate if positive FB in pediatric intensive care unit (PICU) patients with respiratory and/or cardiac failure necessitating ECMO was associated with increased morbidity or mortality. This was a multicenter retrospective cohort study of data from the deidentified PEDiatric ECMO Outcomes Registry (PEDECOR). Patients entered into the database from 2014 to 2017, who received ECMO support, were included. A total of 168 subjects met the study criteria. Univariate analysis showed no significant difference in total FB on ECMO days 1-5 between survivors and non-survivors [median 90 ml/kg (IQR 18-208.5) for survivors vs. median 139.7 ml/kg (IQR 11.2-300.6) for non-survivors, p = 0.334]. There was also no difference in total FB on ECMO days 1-5 in patients with no change in functional outcome as reflected by the Pediatric Outcome Performance Category (POPC) score vs. those who had worsening in POPC score ≥2 at hospital discharge [median 98 ml/kg (IQR 18-267) vs. median 130 ml/kg (IQR 13-252), p = 0.91]. Subjects that required 50 ml/kg or more of blood products over the initial 5 days of ECMO support had an increased rate of mortality with an odds ratio of 5.8 (95% confidence interval of 2.7-12.3; p = 0.048). Our study showed no association of the noted FB with survival after ECMO cannulation. This FB trend was also not associated with POPC at hospital discharge, MV duration, or ECMO duration. The amount of blood product administered was found to be a significant predictor of mortality.

Impact of Acute Kidney Injury on Critically Ill Children and Neonates

Acute kidney injury (AKI) is a clinical syndrome that manifests as an abrupt impairment of kidney function. AKI is common in critically ill pediatric patients admitted to the pediatric intensive care units. AKI is a deleterious complication in critically ill children as it is associated with increased morbidity and mortality. This review provides an overview of the incidence, morbidity, and mortality of AKI in critically ill children in general and specific cohorts such as post-cardiac surgeries, sepsis, critically ill neonates, and post stem cell transplantation.

Early Fluid Accumulation and Intensive Care Unit Mortality in Children Receiving Extracorporeal Membrane Oxygenation

Purpose of this study was to evaluate the impact of early fluid accumulation and renal dysfunction on mortality in children receiving extracorporeal membrane oxygenation (ECMO). Retrospective cohort study of neonatal and pediatric patients who received ECMO between January 2010 and December 2012 in a tertiary level multidisciplinary pediatric intensive care unit (ICU). Ninety-six patients were included, and forty-six (48%) of them received continuous renal replacement therapy (CRRT) during ECMO. Overall mortality was 38.5%. Proportion of patients with acute kidney injury (AKI) at ICU admission was 33% and increased to 47% at ECMO initiation. High-risk diagnoses, extracorporeal cardiopulmonary resuscitation (ECPR), and venoarterial (VA)-ECMO were more common among nonsurvivors. Nonsurvivors had significantly higher proportion of AKI at ICU admission (OR: 2.59, p = 0.04) and fluid accumulation on ECMO day 1 (9% vs. 1%, p = 0.05) compared with survivors. Multivariable logistic regression analysis (adjusted for a propensity score based on nonrenal factors associated with increased mortality) demonstrated that fluid accumulation on ECMO day 1 is significantly associated with increased ICU mortality (OR: 1.07, p = 0.04). Fluid accumulation within the first 24 hours after ECMO cannulation is significantly associated with increased ICU mortality in neonatal and pediatric patients. Prospective studies evaluating the impact of conservative fluid management and CRRT during the initial phase of ECMO may help further define this relationship.

Outcomes of Multiple Runs of Extracorporeal Membrane Oxygenation: An analysis of the Extracorporeal Life Support Registry

OBJECTIVE

When patients deteriorate after decannulation from extracorporeal membrane oxygenation (ECMO), a second run of extracorporeal support may be considered. However, repeat cannulation can be difficult and poor outcomes associated with multiple ECMO runs are a concern. The aim of this study was to evaluate outcomes and identify factors associated with survival and mortality in cases of multiple runs of extracorporeal membrane oxygenation.

DESIGN

Retrospective cohort analysis of the Extracorporeal Life Support Organization Registry.

SETTING

The Extracorporeal Life Support Organization's registry was queried for neonates, children, and adults receiving 2 or more runs of ECMO during the same hospitalization, for any indication, from 1998 to 2015.

PATIENTS

1,818 patients from the Extracorporeal Life Support Organization Registry.

RESULTS

Of the 1,818 patients, 1,648 underwent 2 runs and 170 underwent 3 or more runs of ECMO. The survival to discharge rate was 36.7% for 2 runs and 29.4% for 3 or more runs. No significant differences in survival were detected in analysis by decade of ECMO run (p = 0.21). Pediatric patients had less mortality than adults (OR: 0.45, 95%CI: 0.24-0.82). Cardiac support on the first run portrayed worse mortality than pulmonary support regardless of final run indication (OR:1.38, 95%CI: 1.09-1.75). Across all age groups, patients receiving pulmonary support on the last run tended to have higher survival rates regardless of support type on the first run. The only first run complication independently predictive of mortality on the final run was renal complications (OR: 1.60, 95%CI: 1.28-1.99).

CONCLUSIONS

Though the use of multiple runs of ECMO is growing, outcomes remain poor for most cohorts. Survival decreases with each additional run. Patients requiring additional runs for a pulmonary indication should be considered prime candidates. Renal complications on the first run significantly increases the risk of mortality on subsequent runs, and as such, careful consideration should be applied in these cases.

Review of acute kidney injury and continuous renal replacement therapy in pediatric extracorporeal membrane oxygenation

Purpose

To review the relevant literature of acute kidney injury (AKI) and continuous renal replacement therapy (CRRT) as it relates to pediatric extracorporeal membrane oxygenation (ECMO).

Methods

Available online relevant literature.

Results

ECMO is a therapeutic modality utilized to support patients with refractory respiratory and/or cardiac failure. AKI and fluid overload (FO) are frequently observed in this patient population. There are multiple modalities that can be utilized for AKI and FO which include the following: diuretics, in-line hemofiltration, and CRRT. There are multiple considerations when using CRRT with ECMO including access, CRRT flows, hemolysis, anticoagulation, and CRRT termination.

Conclusion

While each ECMO center has its own set of equipment, experiences, and practices, it is imperative that the international ECMO community continues to work together to provide an evidence-based approach to address the morbidity and mortality associated with AKI and FO.

Acute Kidney Injury, Fluid Overload, and Outcomes in Children Supported With Extracorporeal Membrane Oxygenation for a Respiratory Indication

This study seeks to evaluate the association between acute kidney injury (AKI), fluid overload (FO), and mortality in children supported with extracorporeal membrane oxygenation (ECMO) for refractory respiratory failure. This retrospective observational cohort study was performed at six tertiary care children's hospital intensive care units, studying 424 patients < 18 years of age supported with ECMO for ≥ 24 hours for a respiratory indication from January 1, 2007, to December 31, 2011. In a multivariate analysis, FO level at ECMO initiation was not associated with hospital mortality, whereas peak FO level during ECMO was associated with hospital mortality. For every 10% increase in peak FO during ECMO, the odds of hospital mortality were approximately 1.2 times higher. Every 10% increase in peak FO during ECMO resulted in a significant relative change in the duration of ECMO hours by a factor of 1.08. For hospital survivors, every 10% increase in peak FO level during ECMO resulted in a significant relative change in the duration of mechanical ventilation hours by a factor of 1.13. In this patient population, AKI and FO are associated with increased mortality and should be considered targets for medical interventions including judicious fluid management, diuretic use, and renal replacement therapy.

Recommendations for hemodynamic monitoring for critically ill children-expert consensus statement issued by the cardiovascular dynamics section of the European Society of Paediatric and Neonatal Intensive Care (ESPNIC)

BACKGROUND

Cardiovascular instability is common in critically ill children. There is a scarcity of published high-quality studies to develop meaningful evidence-based hemodynamic monitoring guidelines and hence, with the exception of management of shock, currently there are no published guidelines for hemodynamic monitoring in children. The European Society of Paediatric and Neonatal Intensive Care (ESPNIC) Cardiovascular Dynamics section aimed to provide expert consensus recommendations on hemodynamic monitoring in critically ill children.

METHODS

Creation of a panel of experts in cardiovascular hemodynamic assessment and hemodynamic monitoring and review of relevant literature-a literature search was performed, and recommendations were developed through discussions managed following a Quaker-based consensus technique and evaluating appropriateness using a modified blind RAND/UCLA voting method. The AGREE statement was followed to prepare this document.

RESULTS

Of 100 suggested recommendations across 12 subgroups concerning hemodynamic monitoring in critically ill children, 72 reached "strong agreement," 20 "weak agreement," and 2 had "no agreement." Six statements were considered as redundant after rephrasing of statements following the first round of voting. The agreed 72 recommendations were then coalesced into 36 detailing four key areas of hemodynamic monitoring in the main manuscript. Due to a lack of published evidence to develop evidence-based guidelines, most of the recommendations are based upon expert consensus.

CONCLUSIONS

These expert consensus-based recommendations may be used to guide clinical practice for hemodynamic monitoring in critically ill children, and they may serve as a basis for highlighting gaps in the knowledge base to guide further research in hemodynamic monitoring.