Basics of continuous renal replacement therapy in pediatrics

Dialoxygenation: A Preclinical Trial for Transforming the Artificial Kidney Into an Oxygenator

Critically ill patients sometimes require tandem application of extracorporeal membrane oxygenation (ECMO) and continuous renal replacement therapy (CRRT) which is easier and cheaper. We aimed to transform the kidney membrane into a lung membrane by adding hydrogen peroxide (H2O2) to the dialysate as the oxygen source. A solution containing H2O2 and a dialysate fluid mixture was used as the final dialysate. Starting with 100% H2O2 solution and gradually reducing the volume of H2O2, respectively: 50%, 10%, 5%, 4%, 3%, 2%, and 1%. PRISMAFLEX system, Prismaflex M60 set and a bag of packed red blood cells (pRBCs) were the prototype. blood flow rate was about 40 ml/minute and the dialysis rate was about 200 ml/m2/minute/1.73 m2. blood sampling times were; at the beginning (T0), at 15th (T1), 30th (T2), 60th (T3) minutes. Amongst eight attempts H2O2 concentration that increased the partial oxygen pressure (pO2) level significantly in a reasonable period, without any bubbles, was 3%. Methemoglobinemia was not observed in any trial. After the test with 3%, H2O2 in the dialysate fluid decreased progressively without any H2O2 detection at post-membrane blood. Three percent H2O2 solution is sufficient and safe for oxygenation in CRRT systems. With this new oxy-dialysate solution, both pulmonary and renal replacement can be possible viaa single membrane in a simpler manner.

Epoprostenol (Prostacyclin Analog) as a Sole Anticoagulant in Continuous Renal Replacement Therapy for Critically Ill Children With Liver Disease: Single-Center Retrospective Study, 2010-2019

OBJECTIVES

Despite deranged coagulation, children with liver disease undergoing continuous renal replacement therapy (CRRT) are prone to circuit clotting. Commonly used anticoagulants (i.e., heparin and citrate) can have side effects. The aim of this study was to describe our experience of using epoprostenol (a synthetic prostacyclin analog) as a sole anticoagulant during CRRT in children with liver disease.

DESIGN

Single-center, retrospective study, 2010-2019.

SETTING

Sixteen-bedded PICU within a United Kingdom supra-regional center for pediatric hepatology.

PATIENTS

Children with liver disease admitted to PICU who underwent CRRT anticoagulation with epoprostenol.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Regarding CRRT, we assessed filter life duration, effective 60-hour filter survival, and effective solute clearance. We also assessed the frequency of major or minor bleeding episodes per 1,000 hours of CRRT, the use of platelet and RBC transfusions, and the frequency of hypotensive episodes per 1,000 hours of CRRT. In the 10 years 2010-2019, we used epoprostenol anticoagulation during 353 filter episodes of CRRT, lasting 18,508 hours, in 96 patients (over 108 admissions). Median (interquartile range [IQR]) filter life was 48 (IQR 32-72) hours, and 22.9% of filters clotted. Effective 60-hour filter survival was 60.5%.We identified that 5.9% of filters were complicated by major bleeding (1.13 episodes per 1,000 hr of CRRT), 5.1% (0.97 per 1,000 hr) by minor bleeding, and 11.6% (2.22 per 1,000 hr) by hypotension. There were no differences in filter life or clotting between patients with acute liver failure and other liver diseases; there were no differences in rates of bleeding, hypotension, or transfusion when comparing patients with initial platelets of ≤ 50 × 109 per liter to those with a higher initial count.

CONCLUSIONS

Epoprostenol, or prostacyclin, as the sole anticoagulant for children with liver disease receiving CRRT in PICU, results in a good circuit life, and complications such as bleeding and hypotension are similar to reports using other anticoagulants, despite concerns about coagulopathy in this cohort.

Real-life effects, complications, and outcomes in 39 critically ill neonates receiving continuous kidney replacement therapy

BACKGROUND

Continuous kidney replacement therapy (CKRT) has been expanded from simple kidney replacement therapy to the field of critical illness in children. However, CKRT is rarely used in critically ill neonates in the neonatal intensive care unit (NICU). This study aimed to describe patients' clinical characteristics at admission and CKRT initiation, CKRT effects, short-term outcomes, and predictors of death in critically ill neonates.

METHODS

A 7-year single-center retrospective study in a tertiary NICU.

RESULTS

Thirty-nine critically ill neonates received CKRT between May 2015 and April 2022 with a mortality rate of 35.9%. The most common primary diagnosis was neonatal sepsis in 15 cases (38.5%). Continuous veno-venous hemodiafiltration and continuous veno-venous hemofiltration were applied in 43.6% and 56.4% of neonates, respectively. The duration of CKRT was 44 (18, 72) h. Thirty-one patients (79.5%) had complications due to CKRT-related adverse events, and the most common complication was thrombocytopenia. Approximately 12 h after the CKRT initiation, urine volume, mean arterial pressure, and pH were increased, and serum creatinine, blood urea nitrogen, and blood lactate were decreased. In the multivariate logistic regression analysis, neonatal critical illness score [odds ratio 0.886 (0.786 ~ 0.998), P = 0.046] was an independent risk factor for death in critically ill neonates who received CKRT.

CONCLUSIONS

CKRT can be an effective and feasible technique in critically ill neonates, but the overall mortality and CKRT-related complications are relatively high. Furthermore, the probability of death is greater among neonates with greater severity of illness at CKRT initiation. A higher resolution version of the Graphical abstract is available as Supplementary information.

Safety and efficacy of continuous renal replacement therapy for children less than 10 kg using standard adult machines

Continuous Renal Replacement Therapy (CRRT) machines are used off-label in patients less than 20 kg. Infant and neonates-dedicated CRRT machines are making their way into current practice, but these machines are available only in select centres. This study assesses the safety and efficacy of CRRT using adult CRRT machines in children ≤ 10 kg and to determines the factors affecting the circuit life in these children.

DESIGN

Retrospective cohort study of children ≤ 10 kg who received CRRT (January 2010-January 2018) at a PICU in a tertiary care centre in London, UK. Primary diagnosis, markers for illness severity, CRRT characteristics, length of PICU admission and survival to PICU discharge were collected. Descriptive analysis compared survivors and non-survivors. A subgroup analysis compared children ≤ 5 kg to children 5-10 kg. Fifty-one patients ≤ 10 kg received 10,328 h of CRRT, with median weight of 5 kg. 52.94% survived to hospital discharge. Median circuit life was 44 h (IQR 24-68). Bleeding episodes occurred with 6.7% of sessions and hypotension for 11.9%. Analysis of efficacy showed a reduction in fluid overload at 48 h (P = 0.0002) and serum creatinine at 24 and 48 h (P = 0.001). Blood priming was deemed to be safe as serum potassium decreased at 4 h (P = 0.005); there was no significant change in serum calcium. Survivors had a lower PIM2 score at PICU admission (P < 0.001) and had longer PICU length of stay (P < 0.001).    Conclusion: Pending neonatal and infant dedicated CRRT machines, CRRT can be safely and effectively applied to children weighing ≤ 10 kg using adult-sized CRRT machines.

WHAT IS KNOWN

• Continuous Renal Replacement Therapy can be used for a variety of renal and non-renal indications to improve outcomes for children in the paediatric intensive care unit. These include, persistent oliguria, fluid overload, hyperkalaemia, metabolic acidosis, hyperlactatemia, hyperammonaemia, and hepatic encephalopathy. • Young children ≤ 10 kg are most often treated using standard adult machines, off-label. This potentially places them at risk of side effects due to high extracorporeal circuit volumes, relatively higher blood flows, and difficulty in achieving vascular access.

WHAT IS NEW

• This study found that standard adult machines were effective in reducing fluid overload and creatinine in children ≤ 10 kg. This study also assessed safety of blood priming in this group and found no evidence of an acute fall in haemoglobin or calcium, and a fall in serum potassium by a median of 0.3 mmol/L. The frequency of bleeding episodes was 6.7%, and hypotension requiring vasopressors or fluid resuscitation occurred with 11.9% of treatment sessions. • These findings suggest that adult CRRT machines are sufficiently safe and efficacious for routine use in PICU for children ≤ 10 kg and suggest that further research is undertaken, regarding the routine rollout of dedicated machines.

Acute Kidney Injury: Gaps and Opportunities for Knowledge and Growth

Acute kidney injury (AKI) occurs frequently in hospitalized patients, regardless of age or prior medical history. Increasing awareness of the epidemiologic problem of AKI has directly led to increased study of global recognition, diagnostic tools, both reactive and proactive management, and analysis of long-term sequelae. Many gaps remain, however, and in this article we highlight opportunities to add significantly to the increasing bodies of evidence surrounding AKI. Practical considerations related to initiation, prescription, anticoagulation, and monitoring are discussed. In addition, the importance of AKI follow-up evaluation, particularly for those surviving the receipt of renal replacement therapy, is highlighted as a push for global equity in the realm of critical care nephrology is broached. Addressing these gaps presents an opportunity to impact patient care directly and improve patient outcomes.

The Use of Membranes (ST-100, oXiris, and M60) for Continuous Renal Replacement Therapy in a Child with Sepsis

Sepsis is a critical condition affecting patients worldwide. Systemic inflammatory response syndrome in sepsis contributes to organ dysfunction and mortality. The oXiris is a recently developed continuous renal replacement therapy (CRRT) hemofilter indicated for the adsorption of cytokines from the bloodstream. In our study, in a septic child, CRRT with three filters, including the oXiris hemofilter, resulted in a downregulation of inflammatory biomarkers and a reduction of vasopressors. Herein, we described the first report of such usage in septic children.

Switching from continuous veno-venous hemodiafiltration to intermittent sustained low-efficiency daily hemodiafiltration (SLED-f) in pediatric acute kidney injury: A prospective cohort study

INTRODUCTION

Continuous kidney replacement therapy (CKRT) is the preferred modality in critically ill children with acute kidney injury. Upon improvement, intermittent hemodialysis is usually initiated as a step-down therapy, which can be associated with several adverse events. Hybrid therapies such as Sustained low-efficiency daily dialysis with pre-filter replacement (SLED-f) combines the slow sustained features of a continuous treatment, ensuring hemodynamic stability, with similar solute clearance along with the cost effectiveness of conventional intermittent hemodialysis. We examined the feasibility of using SLED-f as a transition step-down therapy after CKRT in critically ill pediatric patients with acute kidney injury.

METHODS

A prospective cohort study was conducted in children admitted to our tertiary care pediatric intensive care units with multi-organ dysfunction syndrome including acute kidney injury who received CKRT for management. Those patients receiving fewer than two inotropes to maintain perfusion and failed a diuretic challenge were switched to SLED-f.

RESULTS

Eleven patients underwent 105 SLED-f sessions (mean of 9.55 +/- 4.90 sessions per patient), as a part of step-down therapy from continuous hemodiafiltration. All (100%) our patients had sepsis associated acute kidney injury with multiorgan dysfunction and required ventilation. During SLED-f, urea reduction ratio was 64.1 +/- 5.3%, Kt/V was 1.13 +/- 0.1, and beta-2 microglobulin reduction was 42.5 +/-4%. Incidence of hypotension and requirement of escalation of inotropes during SLED-f was 18.18%. Filter clotting occurred twice in one patient.

CONCLUSION

SLED-f is a safe and effective modality for use as a transition therapy between CKRT and intermittent hemodialysis in children in the PICU.

Thrombotic microangiopathies in critically ill children: The MATUCIP registry in Spain

INTRODUCTION

Thrombotic microangiopathies (TMA) are rare diseases usually presenting with renal, haematological, neurologic and cardiovascular involvement and nonspecific but severe symptoms. A registry of TMA cases managed in Spanish paediatric intensive care units (the MATUCIP Registry) was established with the aim of gaining knowledge on their clinical characteristics, diagnosis and acute-phase treatment.

METHODS

We conducted a prospective multicentre observational study in 20 paediatric intensive care units (PICUs) in Spain from January 2017 to December 2021 in children aged more than 1 month with TMAs, who were followed up through the discharge from the PICU.

RESULTS

The sample included 97 patients (51.5% female) with a median age of 2.6 years (interquartile range [IQR], 1.6-5.7). The initial manifestations were gastrointestinal (74.2%), respiratory (14.4%), fever (5.2%), neurologic (3.1%) and other (3.1%). At admission, 75.3% of patients had microangiopathic haemolytic anaemia, 95.9% thrombocytopenia and 94.8% acute kidney injury. Of the total sample, 57.7% of patients received a diagnosis of Shiga toxin-associated haemolytic uraemic syndrome (HUS), 14.4% of Streptococcus pneumoniae-associated HUS, 15.6% of atypical HUS, 10.3% of secondary TMA and 2.1% of thrombotic thrombocytopenic purpura. Eighty-seven patients (89.7%) developed arterial hypertension, and 49.5% gastrointestinal, 22.7% respiratory, 25.8% neurologic and 12.4% cardiac manifestations. Also, 60.8% required renal replacement therapy and 2.1% plasma exchange. Twenty patients received eculizumab. The median PICU stay was 8.5 days (IQR, 5-16.5). Two children died.

CONCLUSIONS

The MATUCIP registry demonstrates the clinical variability of TMA cases requiring admission to the PICU. Knowledge of the presentation and outcomes of TMAs can facilitate early aetiological diagnosis. This registry can help improve our understanding of the clinical spectrum of these diseases, for which there is a dearth of published data.

Analysis of risk factors for death in 59 cases of critically ill neonates receiving continuous renal replacement therapy: a two-centered retrospective study

To investigate the risk factors for death in critically ill neonates receiving continuous renal replacement therapy (CRRT). This retrospective study analyzed the clinical data of critically ill neonates receiving CRRT at two tertiary hospitals from January 2015 to December 2021. A multi-factor logistic regression analysis was performed, and the predictive value of relevant risk factors on death was verified by receiver operating characteristic (ROC) curve. A total of 59 cases of critically ill neonates were included in this study, with a mortality of 37.3%. The most common primary disease in these cases was neonatal sepsis, followed by neonatal asphyxia, and inborn errors of metabolism (IEM). Univariate analysis showed that the risk factors related to death included primary diseases; the number of organs involved in multiple organ dysfunction syndrome (MODS), neonatal critical illness scores (NCIS), and indications of CRRT; the blood lactate, blood glucose, hemoglobin, and platelet before CRRT initiation; and the incidence of bleeding or thrombosis during CRRT. Multi-factor logistic regression analysis showed that risk factors for death in critically ill neonates receiving CRRT included the occurrence of neonatal sepsis, the number of organs involved in MODS, and the NCIS. ROC curve analysis showed that the number of organs involved in MODS and NCIS had a good predictive value for death in critically ill neonates receiving CRRT, with the areas under the curve (AUC) being 0.700 and 0.810, respectively.

CONCLUSION

Neonatal sepsis, the number of organs involved in MODS, and NCIS were independent risk factors for death in critically ill neonates receiving CRRT. Moreover, the number of organs involved in MODS and NCIS could effectively predict death in critically ill neonates receiving CRRT.

WHAT IS KNOWN

• The population to which CRRT is applicable is gradually expanding from critically ill children to critically ill neonates. • The mortality of critically ill neonates receiving CRRT remains high.

WHAT IS NEW

• The most common primary disease in critically ill neonates receiving CRRT was neonatal sepsis, followed by neonatal asphyxia and inborn errors of metabolism (IEM). • The number of organs involved in MODS and NCIS could effectively predict death in critically ill neonates receiving CRRT.

β-lactam precision dosing in critically ill children: Current state and knowledge gaps

There has been emerging interest in implementing therapeutic drug monitoring and model-informed precision dosing of β-lactam antibiotics in critically ill patients, including children. Despite a position paper endorsed by multiple international societies that support these efforts in critically ill adults, implementation of β-lactam precision dosing has not been widely adopted. In this review, we highlight what is known about β-lactam antibiotic pharmacokinetics and pharmacodynamics in critically ill children. We also define the knowledge gaps that present barriers to acceptance and implementation of precision dosing of β-lactam antibiotics in critically ill children: a lack of consensus on which subpopulations would benefit most from precision dosing and the uncertainty of how precision dosing changes outcomes. We conclude with opportunities for further research to close these knowledge gaps.

Dexmethylphenidate-Induced Rhabdomyolysis by Interaction With Aromatase Inhibitor

Rhabdomyolysis secondary to prescription drug-drug interactions can be an overlooked life-threatening emergency. Amphetamines and similar substances have been associated with muscle lysis secondary to increased sympathetic activity that can cause myotoxicity, hyperthermia, and increased muscular activity. Anabolic steroids may also be a predisposing factor in developing rhabdomyolysis. A high index of suspicion for drug-induced rhabdomyolysis in a patient presenting with atraumatic extremity pain can facilitate rapid diagnosis and treatment. We present a case of drug-induced rhabdomyolysis likely secondary to a previously unreported medication interaction.

Regional Citrate Anticoagulation and Systemic Anticoagulation during Pediatric Continuous Renal Replacement Therapy: A Systematic Literature Review

Background: Clotting is a major drawback of continuous renal replacement therapy (CRRT) performed on critically ill pediatric patients. Although anticoagulation is recommended to prevent clotting, limited results are available on the effect of each pharmacological strategy in reducing filter clotting in pediatric CRRT. This study defines which anticoagulation strategy, between regional citrate anticoagulation (RCA) and systemic anticoagulation with heparin, is safer and more efficient in reducing clotting, patient mortality, and treatment complications during pediatric CRRT. Methods: A systematic literature review was run considering papers published in English until December 2021 and describing patients’ and treatments’ complications in CRRT performed with heparin and RCA on patients aged less than 18 years. Results: Eleven studies were considered, cumulatively comprising 1.706 CRRT sessions (62% with systemic anticoagulation and 38% with RCA). Studies have consistently identified RCA’s superiority over systemic anticoagulation with heparin in prolonging circuit life. The pooled estimate (95% CI) of filter clotting risk showed that RCA is a protective factor for clotting risk (RR = 0.204). Conclusions: RCA has a potential role in prolonging circuit life and seems superior to systemic anticoagulation with heparin in decreasing the risk of circuit clotting during CRRT performed in critically ill pediatric patients.

Pharmacokinetics of Commonly Used Medications in Children Receiving Continuous Renal Replacement Therapy: A Systematic Review of Current Literature

BACKGROUND AND OBJECTIVE

The use of continuous renal replacement therapy (CRRT) for renal support has increased substantially in critically ill children compared with intermittent modalities owing to its preferential effects on hemodynamic stability. With the expanding role of CRRT, the quantification of extracorporeal clearance and the effect on primary pharmacokinetic parameters is of the utmost importance. Within this review, we aimed to summarize the current state of the literature and compare published pharmacokinetic analyses of commonly used medications in children receiving CRRT to those who are not.

METHODS

A systematic search of the literature within electronic databases PubMed, EMBASE, Cochrane Library, and Web of Science was conducted. Published studies that were included contained relevant information on the use of commonly administered medications to children, from neonates to adolescents, receiving CRRT. Pharmacokinetic parameters that were analyzed included volume of distribution, total clearance, extracorporeal clearance, area under the curve, and elimination half-life. Information regarding CRRT circuit, flow rates, and membrane components was analyzed to investigate differences in pharmacokinetics between each modality.

RESULTS

Forty-five studies met the final inclusion criteria within this systematic review, totaling 833 pediatric patients, with 586 receiving CRRT. Antimicrobials were the most common pharmacological class represented within the literature, representing 81% (35/43) of studies analyzed. Children receiving CRRT largely had similar volume of distribution and total clearance to critically ill children not receiving CRRT, suggesting reno-protective dose adjustments may lead to subtherapeutic dosing regimens in these patients. Overall, there was a tendency for hydrophilic agents, with a low protein binding to undergo elevated total clearance in these children. However, results should be interpreted with caution because of the large variability amongst patient populations and heterogeneity with CRRT modalities, flow rates, and use of extracorporeal membrane oxygenation within studies. This review was able to identify that variation in solute removal, or CRRT modalities, properties (i.e., flow rates), and membrane composition, may have differing effects on the pharmacokinetics of commonly administered medications.

CONCLUSIONS

The current state of the literature regarding medications administered to children receiving CRRT largely focuses on antimicrobials. Significant gaps remain with other commonly used medications such as sedatives and analgesics. Overall reporting of patient clinical characteristics, CRRT settings, and circuit composition was poor, with only 10% of articles including all relevant information to assess the impact of CRRT on total clearance. Changes in pharmacokinetics because of CRRT often required higher than labeled doses, suggesting renally adjusted or reno-protective doses may lead to subtherapeutic dosing regimens. A thorough understanding of the interplay between patient, drug, and CRRT-circuit factors are required to ensure adequate delivery of dosing regimens to this vulnerable population.

Lessons Learned from a Small Pediatric Continuous Renal Replacement Therapy Program

Continuous renal replacement therapy (CRRT) has become a pillar of care in pediatric intensive care units (PICUs) over the past few decades. Quality indicators (QIs) have been evaluated that reflect safe and accountable CRRT. However, there is a paucity of data on outcomes and QIs in smaller-volume CRRT programming. The purpose of this retrospective study was to evaluate the efficiencies, effectiveness, and outcomes of a small-volume CRRT program. Eighty-two patients received CRRT over a 13-year period, and 79% survived to discharge. Sepsis or nonseptic shock (n = 11 (22%) versus n = 6 (50%); p value = 0.004) and time to CRRT initiation after PICU admission (1.1 versus 5.0 days; p value = 0.005) were independent predictors for mortality. The program also had positive outcomes for QIs related to CRRT efficiency and time of initiation, dosing delivery, and rate of adverse events. This study is important as it illustrates the opportunity that smaller centers have to initiate CRRT programming and provide safe and effective care.

Pharmacokinetics of Antibiotics in Pediatric Intensive Care: Fostering Variability to Attain Precision Medicine

Children show important developmental and maturational changes, which may contribute greatly to pharmacokinetic (PK) variability observed in pediatric patients. These PK alterations are further enhanced by disease-related, non-maturational factors. Specific to the intensive care setting, such factors include critical illness, inflammatory status, augmented renal clearance (ARC), as well as therapeutic interventions (e.g., extracorporeal organ support systems or whole-body hypothermia [WBH]). This narrative review illustrates the relevance of both maturational and non-maturational changes in absorption, distribution, metabolism, and excretion (ADME) applied to antibiotics. It hereby provides a focused assessment of the available literature on the impact of critical illness—in general, and in specific subpopulations (ARC, extracorporeal organ support systems, WBH)—on PK and potential underexposure in children and neonates. Overall, literature discussing antibiotic PK alterations in pediatric intensive care is scarce. Most studies describe antibiotics commonly monitored in clinical practice such as vancomycin and aminoglycosides. Because of the large PK variability, therapeutic drug monitoring, further extended to other antibiotics, and integration of model-informed precision dosing in clinical practice are suggested to optimise antibiotic dose and exposure in each newborn, infant, or child during intensive care.

Kidney support therapy in the pediatric patient: Unique considerations for a unique population

The use of kidney support therapy (KST) for use in managing patients with acute kidney injury (AKI) has expanded greatly in the last several decades. The growing use of KST modalities in children, and now in neonates, has been associated with opportunities for education, clinical research, clinical practice improvements, and outcomes research. A multitude of controversies exist in the field of pediatric KST-many of which are shared by adult critical care nephrology practice. Simultaneously, pediatric KST has led the way to a burgeoning exploration of the importance of fluid overload as it relates to KST initiation and management and also with quality improvement. In this review, we will explore and describe the paradigms contained with pediatric KST used to support children with AKI. In addition to the governing principles related to the mechanics of KST, we will describe the novel aspects of newer support machines and ethical considerations of KST provision. Anticoagulation, dose, and modality will be discussed as well as priming procedures for special considerations. The utilization of KST across pediatric populations represents the next frontier of critical care nephrology.

Kidney Replacement Therapy in COVID-19 Induced Kidney Failure and Septic Shock: A Pediatric Continuous Renal Replacement Therapy [PCRRT] Position on Emergency Preparedness With Resource Allocation

The recent worldwide pandemic of COVID-19 has had a detrimental worldwide impact on people of all ages. Although data from China and the United States indicate that pediatric cases often have a mild course and are less severe in comparison to adults, there have been several cases of kidney failure and multisystem inflammatory syndrome reported. As such, we believe that the world should be prepared if the severity of cases begins to further increase within the pediatric population. Therefore, we provide here a position paper centered on emergency preparation with resource allocation for critical COVID-19 cases within the pediatric population, specifically where renal conditions worsen due to the onset of AKI.