Pediatric continuous renal replacement: 20 years later

Pediatric continuous kidney replacement therapy: The Indonesian experience

BACKGROUND

Acute kidney injury (AKI) is a common complication in critically ill children, with continuous kidney replacement therapy (CKRT) as the key treatment, especially for hemodynamically unstable children. Although numerous studies have been conducted on CKRT, data from resource-constrained settings are scarce. Centers with more experience in CKRT tend to have better survival rates. This study aims to describe and analyze the characteristics of critically ill patients who received CKRT and examine the factors influencing CKRT outcomes in resource-limited settings.

METHODS

A retrospective analysis was conducted on medical records from January 2015 to June 2023. Demographic data; clinical and laboratory profiles; hospitalization duration; use of inotropic support and mechanical ventilation; and the presence of sepsis, AKI, acute lung injury, acute respiratory distress syndrome, and encephalopathy were recorded and compared between survivors and non-survivors.

RESULTS

Fifty-six critically ill children underwent CKRT. The median age was 7.4 years, and the median body weight was 22.2 kg. CKRT was mostly indicated in sepsis-associated AKI (41.1%), nonsepsis AKI (23.2%), and acute-on-chronic kidney disease (21.4%). The median CKRT duration was 52.2 h, with median total delivered dose and mean blood flow rate per kilogram of 22.2 and 3.1 mL/kg/min, respectively. The overall survival rate was 25%.

CONCLUSIONS

Although patient demographics and CKRT prescriptions were like those at other centers, survival was low at our center because of considerable resource limitations. Despite challenges, CKRT remains the preferred treatment for critically ill children.

Continuous renal replacement therapy in neonates and children: what does the pediatrician need to know? An overview from the Critical Care Nephrology Section of the European Society of Paediatric and Neonatal Intensive Care (ESPNIC)

Continuous renal replacement therapy (CRRT) is the preferred method for renal support in critically ill and hemodynamically unstable children in the pediatric intensive care unit (PICU) as it allows for gentle removal of fluids and solutes. The most frequent indications for CRRT include acute kidney injury (AKI) and fluid overload (FO) as well as non-renal indications such as removal of toxic metabolites in acute liver failure, inborn errors of metabolism, and intoxications and removal of inflammatory mediators in sepsis. AKI and/or FO are common in critically ill children and their presence is associated with worse outcomes. Therefore, early recognition of AKI and FO is important and timely transfer of patients who might require CRRT to a center with institutional expertise should be considered. Although CRRT has been increasingly used in the critical care setting, due to the lack of standardized recommendations, wide practice variations exist regarding the main aspects of CRRT application in critically ill children.     Conclusion: In this review, from the Critical Care Nephrology section of the European Society of Paediatric and Neonatal Intensive Care (ESPNIC), we summarize the key aspects of CRRT delivery and highlight the importance of adequate follow up among AKI survivors which might be of relevance for the general pediatric community. What is Known: • CRRT is the preferred method of renal support in critically ill and hemodynamically unstable children in the PICU as it allows for gentle removal of fluids and solutes. • Although CRRT has become an important and integral part of modern pediatric critical care, wide practice variations exist in all aspects of CRRT. What is New: • Given the lack of literature on guidance for a general pediatrician on when to refer a child for CRRT, we recommend timely transfer to a center with institutional expertise in CRRT, as both worsening AKI and FO have been associated with increased mortality. • Adequate follow-up of PICU patients with AKI and CRRT is highlighted as recent findings demonstrate that these children are at increased risk for adverse long-term outcomes.

New perspectives in pediatric dialysis technologies: the case for neonates and infants with acute kidney injury

Advancements in pediatric dialysis generally rely on adaptation of technology originally developed for adults. However, in the last decade, particular attention has been paid to neonatal extracorporeal therapies for acute kidney care, an area in which technology has made giant strides in recent years. Peritoneal dialysis (PD) is the kidney replacement therapy (KRT) of choice in the youngest age group because of its simplicity and effectiveness. However, extracorporeal blood purification provides more rapid clearance of solutes and faster fluid removal. Hemodialysis (HD) and continuous KRT (CKRT) are thus the most used dialysis modalities for pediatric acute kidney injury (AKI) in developed countries. The utilization of extracorporeal dialysis for small children is associated with a series of clinical and technical challenges which have discouraged the use of CKRT in this population. The revolution in the management of AKI in newborns has started recently with the development of new CKRT machines for small infants. These new devices have a small extracorporeal volume that potentially prevents the use of blood to prime lines and dialyzer, allow a better volume control and the use of small-sized catheter without compromising the blood flow amount. Thanks to the development of new dedicated devices, we are currently dealing with a true "scientific revolution" in the management of neonates and infants who require an acute kidney support.

Clinical features and risk factors associated with mortality in critically ill children requiring continuous renal replacement therapy

INTRODUCTION

The aims of this study were to describe the demographic characteristics of critically ill children requiring continuous renal replacement therapy (CRRT) at our pediatric intensive care unit (PICU) and to explore risk factors associated with mortality.

METHODS

A retrospective cohort of 121 critically ill children who received CRRT from May 2015 to May 2020 in the PICU of a tertiary healthcare institution was evaluated.

RESULTS

Overall mortality was 29.8%. In patients diagnosed with sepsis, time until CRRT initiation was significantly shorter in survivors compared to non-survivors (p = 0.036). Based on multivariate logistic regression, presence of comorbidity (OR: 5.71), diagnoses of pneumonia/respiratory failure at admission (OR:16.16), and high lactate level at CRRT initiation (OR:1.43) were independently associated with mortality.

CONCLUSION

In the context of the population studied, mortality rate was lower than previously reported. Despite having a large series, heterogenous characteristics and limitations in subgroups may have influenced results and survival. This article is protected by copyright. All rights reserved.

SOFA score is superior to APACHE-II score in predicting the prognosis of critically ill patients with acute kidney injury undergoing continuous renal replacement therapy

Background

Acute kidney injury (AKI) is the most common cause of organ failure in multiple organ dysfunction syndrome (MODS) and is associated with increased mortality. This study aimed at determining the efficacy of sequential organ failure assessment (SOFA), and acute physiology and chronic health evaluation II (APACHE-II) scoring systems in assessing the prognosis of critically ill patients with AKI undergoing continuous renal replacement therapy (CRRT). At present, APACHE-II score and SOFA score were also used to evaluate and predict the prognosis of critically ill patients with AKI.

Methods

The predictive value of SOFA and APACHE-II scores for 28- and 90-d mortality in patients with AKI undergoing CRRT were determined by multivariate analysis, sensitivity analysis, and curve-fitting analysis.

Results

A total of 836 cases were included in this study. Multivariate Cox logistic regression analysis showed that SOFA scores were associated with 28- and 90-d mortality in patients with AKI undergoing CRRT. The adjusted HR of SOFA for 28-d mortality were 1.18 (1.14, 1.21), 1.24 (1.18, 1.31), and 1.19 (1.13, 1.24) in the three models, respectively, and the adjusted HR of SOFA for 90-d mortality was 1.12 (1.09, 1.16), 1.15 (1.10, 1.19), and 1.15 (1.10, 1.19), respectively. The subgroup analysis showed that the SOFA score was associated with 28-d and 90-d mortality in patients with AKI undergoing CRRT. APACHE-II score was not associated with 28- and 90-d mortality patients with AKI undergoing CRRT. Curve fitting analysis showed that SOFA scores increased had a higher prediction accuracy for 28- and 90-d than APACHE-II.

Conclusions

The SOFA score showed a higher accuracy of mortality prediction in critically ill patients with AKI undergoing CRRT than the APACHE-II score.

The Effect of Patient- and Treatment-Related Factors on Circuit Lifespan During Continuous Renal Replacement Therapy in Critically Ill Children

OBJECTIVES

To examine the effects of patient and treatment variables on circuit lifespan in critically ill children requiring continuous renal replacement therapy.

DESIGN

Retrospective observational study based on a prospective registry.

SETTING

Tertiary referral 30-bed PICU.

PATIENTS

One hundred sixty-one critically ill children undergoing continuous renal replacement therapy during an 8-year period (2007-2014) were included in the study.

INTERVENTIONS

Continuous renal replacement therapy.

MEASUREMENTS AND MAIN RESULTS

During the study period, 161 patients received a total of 22,190 hours of continuous renal replacement therapy, with a median duration of 74.75 hours (interquartile range, 32-169.5) per patient. Of the 572 filter circuits used, 276 (48.3%) were changed due to circuit clotting and 262 (45.8%) were electively changed. Median circuit life was 24.62 hours (interquartile range, 10.6-55.3) for all filters and significantly longer for those electively removed as compared to those prematurely removed because of clotting (35.50 hr [interquartile range, 16.9-67.6] vs 22.00 hr [interquartile range, 13.8-42.5]; p < 0.001). Multivariate regression analyses revealed that admission diagnosis (p < 0.001), anticoagulation type (p < 0.001), access type (p = 0.016), and circuit size (p = 0.027) were associated with prolonged circuit life, as well as, in patients on heparin anticoagulation, with higher doses of heparin (p < 0.001) and a prolonged activated partial thromboplastin time (p < 0.001).

CONCLUSIONS

In this study, circuit lifespan in pediatric continuous renal replacement therapy was low and appeared to depend upon the patient's diagnosis, the type of access and anticoagulation used as well as the size of the circuit used.

Mortality of Critically Ill Children Requiring Continuous Renal Replacement Therapy: Effect of Fluid Overload, Underlying Disease, and Timing of Initiation

OBJECTIVE

To identify risk factors associated with mortality in critically ill children requiring continuous renal replacement therapy.

DESIGN

Retrospective observational study based on a prospective registry.

SETTING

Tertiary and quaternary referral 30-bed PICU.

PATIENTS

Critically ill children undergoing continuous renal replacement therapy were included in the study.

INTERVENTIONS

Continuous renal replacement therapy.

MEASUREMENTS AND MAIN RESULTS

Overall mortality was 36% (n = 58) among the 161 patients treated with continuous renal replacement therapy during the study period and was significantly higher in patients on extracorporeal membrane oxygenation (47.5%, 28 of 59) than in patients not requiring extracorporeal membrane oxygenation (28.4%, 29 of 102; p = 0.022). According to the admission diagnosis, we found the highest mortality in patients with onco-hematologic disease (77.8%) and the lowest in patients with renal disease (5.6%). Based on multivariate logistic regression analysis, the presence of higher severity of illness score at admission (adjusted odds ratio, 1.49; 95% CI, 1.18-1.89; p < 0.001), onco-hematologic disease (odds ratio, 17.10; 95% CI, 4.10-72.17; p < 0.001), fluid overload 10%-20% (odds ratio, 3.83; 95% CI, 1.33-11.07; p = 0.013), greater than 20% (odds ratio, 15.03; 95% CI, 4.03-56.05; p < 0.001), and timing of initiation of continuous renal replacement therapy (odds ratio, 1.01; 95% CI, 1.00-1.01; p = 0.040) were independently associated with mortality. In our population, the odds of dying increases by 1% for every hour of delay in continuous renal replacement therapy initiation from ICU admission.

CONCLUSIONS

Mortality in children requiring continuous renal replacement therapy remains high and seems to be related to the underlying disease, the severity of illness, and the degree of fluid overload. In critically ill children at high risk for developing acute kidney injury and fluid overload, earlier initiation of continuous renal replacement therapy might result in decreased mortality.

A Report of 7-Year Experience on Pediatric Continuous Renal Replacement Therapy

BACKGROUND

Continuous renal replacement therapies (CRRTs) either as continuous venovenous hemofiltration (CVVH) or hemodiafiltration (CVVHD) are used frequently in critically ill children. Many clinical variables and technical issues are known to affect the result. The factors that could be modified to increase the survival of renal replacement are sought. As a contribution, we present the data on 104 patients who underwent CRRT within a 7-year period.

MATERIALS AND METHOD

A total of 104 patients admitted between 2009 and 2016 were included in the study. The demographic information, admittance pediatric risk of mortality (PRISM) scores, indication for CRRT, presence of fluid overload, CRRT modality, durations of CRRT, and pediatric intensive care unit (PICU) stay were compared between survivors and nonsurvivors.

RESULTS

The overall rate of survival was 51%. Patients with fluid overload had significantly increased rate of death, CRRT duration, and PICU stay. Multiorgan dysfunction syndrome as the indication for CRRT was significantly related to decreased survival when compared to acute renal failure and acute attacks of metabolic diseases. The CRRT modality was not different between survivors and nonsurvivors. Standardized mortality ratio of the group was calculated to be 0.8.

CONCLUSION

The CRRT in critically ill patients is successful in achieving fluid removal and correction of metabolic imbalances caused by organ failures or attacks of inborn errors of metabolism. It has a positive effect on expected mortality in high-risk PICU patients. To affect the outcome, follow-up should be focused on starting therapy in early stages of fluid overload. Prospective studies defining relative importance of risk factors causing mortality can assist in building up guidelines to affect the outcome.

Continuous Renal Replacement Therapy: Forty-year Anniversary

In 1977 Peter Kramer performed the first CAVH (continuous arteriovenous hemofiltration) treatment in Gottingen, Germany. CAVH soon became a reliable alternative to hemo- or peritoneal dialysis in critically ill patients. The limitations of CAVH spurred new research and the discovery of new treatments such as CVVH and CVVHD (continuous veno-venous hemofiltration and continuous veno-venous hemodialysis). The alliance with industry led to development of new specialized equipment with improved accuracy and performance in delivering continuous renal replacement therapies (CRRTs). Machines and filters have progressively undergone a series of technological steps, reaching a high level of sophistication. The evolution of technology has continued, leading to the development and clinical application of new membranes, new techniques and new treatment modalities. With the progress of technology, the entire field of critical care nephrology moved forward, expanding the areas of application of extracorporeal therapies to cardiac, liver and pulmonary support. A great deal of research made extracorporeal therapies an interesting option for the treatment of sepsis and intoxication and the additional use of sorbents was explored. With the progress in understanding the pathophysiology of acute kidney injury (AKI), new guidelines were developed, driving indications, modalities of prescription, monitoring techniques and quality assurance programs. Information technology and precision medicine have recently contributed to further evolution of CRRT, with the possibility of collecting data in large databases and evaluating policies and practice patterns. This is likely to ultimately result in improved patient care. CRRTs are 40 years old today, but they are still young and full of potential for further evolution.

CVVHD treatment with CARPEDIEM: small solute clearance at different blood and dialysate flows with three different surface area filter configurations

BACKGROUND

The CARdiorenal PEDIatric EMergency (CARPEDIEM) machine was originally designed to perform only continuous venovenous hemofiltration (CVVH) in neonatal and pediatric patients. In some cases, adequate convective clearance may not be reached because of a limited blood flow. In such conditions, the application of diffusive clearance [continuous venovenous hemodialysis (CVVHD)] would help optimize blood purification. In this study, the CARPEDIEM™ machine was modified to enable the circulation of dialysis through the filter allowing testing of the performance of CARPEDIEM™ machine in CVVHD.

METHODS

Three different polyethersulfone hemodialyzers (surface area = 0.1 m(2), 0.2 m(2), and 0.35 m(2), respectively) were tested in vitro with a scheduled combination of plasma flow rates (Qp = 10-20-30 ml/min) and dialysis fluid flow rate (Qd = 5-10-15 ml/min). Three sessions were performed in co-current and one in counter-current configuration (as control) for each filter size. Clearance was measured from the blood and dialysate sides and results with mass balance error greater than 5 % were discarded.

RESULTS

Urea and creatinine clearances for each plasma/dialysate combination are reported: clearance increase progressively for every filter proportionally to plasma flow rates. Similarly, clearances increase progressively with dialysate flow rates at a given plasma flow. The clearance curve tends to present a steep increase for small increases in plasma flow in the range below 10 ml/min, while the curve tends to plateau for values averaging 30 ml/min. As expected, the plateau is reached earlier with the smaller filter showing the effect of membrane surface-area limitation. At every plasma flow, the effect of dialysate flow increase is evident and well defined, showing that saturation of effluent was not achieved completely in any of the experimental conditions explored. No differences (p > 0.05 for all values) were obtained in experiments using whole blood instead of plasma or using co-current versus counter-current dialysate flow configuration.

CONCLUSIONS

Although plasma flow and filter surface give an important contribution to the level of clearance urea and creatinine, it appears evident that dialysate flow plays an essential role in the blood purification process, justifying the use of CVVHD versus CVVH in case of high dialysis dose requirement and/or limited blood flow rate.