Heparin free dialysis in critically sick children using sustained low efficiency dialysis (SLEDD-f): A new hybrid therapy for dialysis in developing world

Archetypal sustained low-efficiency daily diafiltration (SLEDD-f) for critically ill patients requiring kidney replacement therapy: towards an adequate therapy

Sustained low-efficiency dialysis is a hybrid form of kidney replacement therapy that has gained increasing popularity as an alternative to continuous forms of kidney replacement therapy in intensive care unit settings. During the COVID-19 pandemic, the shortage of continuous kidney replacement therapy equipment led to increasing usage of sustained low-efficiency dialysis as an alternative treatment for acute kidney injury. Sustained low-efficiency dialysis is an efficient method for treating hemodynamically unstable patients and is quite widely available, making it especially useful in resource-limited settings. In this review, we aim to discuss the various attributes of sustained low-efficiency dialysis and how it is comparable to continuous kidney replacement therapy in efficacy, in terms of solute kinetics and urea clearance, and the various formulae used to compare intermittent and continuous forms of kidney replacement therapy, along with hemodynamic stability. During the COVID-19 pandemic, there was increased clotting of continuous kidney replacement therapy circuits, which led to increased use of sustained low-efficiency dialysis alone or together with extra corporeal membrane oxygenation circuits. Although sustained low-efficiency dialysis can be delivered with continuous kidney replacement therapy machines, most centers use standard hemodialysis machines or batch dialysis systems. Even though antibiotic dosing differs between continuous kidney replacement therapy and sustained low-efficiency dialysis, reports of patient survival and renal recovery are similar for continuous kidney replacement therapy and sustained low-efficiency dialysis. Health care studies indicate that sustained low-efficiency dialysis has emerged as a cost-effective alternative to continuous kidney replacement therapy. Although there is considerable data to support sustained low-efficiency dialysis treatments for critically ill adult patients with acute kidney injury, there are fewer pediatric data, even so, currently available studies support the use of sustained low-efficiency dialysis for pediatric patients, particularly in resource-limited settings.

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.

Feasibility and Efficacy of Sustained Low-Efficiency Dialysis in Critically Ill Children with Severe Acute Kidney Injury

OBJECTIVES

To examine the feasibility, efficacy, and safety of sustained low-efficiency dialysis (SLED) in hemodynamically unstable, critically ill children.

METHODS

Critically ill patients, 1-18 y old with hemodynamic instability (≥ 1 vasoactive drugs) and severe acute kidney injury (AKI) requiring kidney replacement therapy (KRT) in a tertiary care pediatric intensive care unit were prospectively enrolled. Patients weighing ≤ 8 kg or with mean arterial pressure < 5^th percentile despite > 3 vasoactive drugs, were excluded. Patients underwent SLED until hemodynamically stable and off vasoactive drugs, or lack of need for dialysis. The primary outcome was the proportion of patients in whom the first session of SLED was initiated within 12 h of its indication and completed without premature (< 6 h) termination. Efficacy was estimated by ultrafiltration, urea reduction ratio (URR), and equilibrated Kt/V. Other outcomes included: changes in hemodynamic scores, circuit clotting, adverse events, and changes in indices on point-of-care ultrasonography and echocardiography.

RESULTS

Between November 2018 and March 2020, 18 patients with median age 8.6 y and vasopressor dependency index of 83.2, underwent 41 sessions of SLED. In 16 patients, SLED was feasible within 12 h of indication. No session was terminated prematurely. Ultrafiltration achieved was 4.0 ± 2.2 mL/kg/h, while URR was 57.7 ± 16.2% and eKt/V 1.17 ± 0.56. Hemodynamic scores did not change significantly. Asymptomatic hypokalemia was the chief adverse effect. Sessions were associated with a significant improvement in indices on ultrasound and left ventricular function. Fourteen patients died.

CONCLUSIONS

SLED is feasible, safe, and effective in enabling KRT in hemodynamically unstable children with severe AKI.

Sustained Low Efficiency Dialysis in Critically Ill Children With Acute Kidney Injury: Single-Center Observational Cohort in a Resource-Limited Setting

OBJECTIVES

To evaluate use of sustained low efficiency dialysis (SLED) in critically ill children with acute kidney injury in a resource-limited setting.

DESIGN

Observational database cohort study (December 2016 to January 2020).

SETTING

PICU of a tertiary hospital in India.

PATIENTS

Critically ill children undergoing SLED were included in the study.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Demographic and clinical data, prescription variables, hemodynamic status, complications, kidney, and patient outcomes of all children undergoing SLED in the PICU were analyzed. A total of 33 children received 103 sessions of SLED. The median (interquartile range, IQR) age and weight of children who received SLED were 9 years (4.5-12.8 yr) and 26 kg (15.2-34 kg), respectively. The most common diagnosis was sepsis with septic shock in 17 patients, and the mean (± sd ) Pediatric Risk of Mortality III score at admission was 11.8 (±6.4). The median (IQR) number and mean (± sd ) duration of inotropes per session were 3 hours (2-4 hr) and 96 (±82) hours, respectively. Of 103 sessions, the most common indication for SLED was oligoanuria with fluid overload and the need for creating space for fluid and nutritional support in 45 sessions (44%). The mean (± sd ) duration of SLED was 6.4 (±1.3) hours with 72 of 103 sessions requiring priming. The mean (± sd ) ultrafiltration rate per session achieved was 4.6 (±3) mL/kg/hr. There was significant decrease in urea and creatinine by end of SLED compared with the start, with mean change in urea and serum creatinine being 32.36 mg/dL (95% CI, 18.53-46.18 mg/dL) ( p < 0.001) and 0.70 mg/dL (95% CI, 0.35-1.06 mg/dL) ( p < 0.001), respectively. Complications were observed in 44 of 103 sessions, most common being intradialytic hypotension (21/103) and bleeding at the catheter site (21/103). Despite complications in one third of the sessions, only nine sessions were prematurely stopped, and 23 of 33 patients receiving SLED survived.

CONCLUSION

In critically ill children, our experience with SLED is that it is feasible and provides a viable form of kidney replacement therapy in a resource-limited setting.

Anticoagulation in patients with acute kidney injury undergoing kidney replacement therapy

Kidney replacement therapy (KRT) is used to provide supportive therapy for critically ill patients with severe acute kidney injury and various other non-renal indications. Modalities of KRT include continuous KRT (CKRT), intermittent hemodialysis (HD), and sustained low efficiency daily dialysis (SLED). However, circuit clotting is a major complication that has been investigated extensively. Extracorporeal circuit clotting can cause reduction in solute clearances and can cause blood loss, leading to an upsurge in treatment costs and a rise in workload intensity. In this educational review, we discuss the pathophysiology of the clotting cascade within an extracorporeal circuit and the use of various types of anticoagulant methods in various pediatric KRT modalities.

Renal replacement therapy for acute kidney injury in burn patients, an international survey and a qualitative review of current controversies

BACKGROUND OF THE STUDY

Acute kidney injury (AKI) is a common complication in critically ill burn patients and is associated with a number of serious adverse outcomes. The clinical decision-making process related to the management of AKI in burn patients is complex and has not been sufficiently standardized. The main aim of this study was to explore the diagnostic approach and clinician's attitudes toward the management of AKI and RRT in burn patients around the world.

METHODS

The questionnaire was widely distributed among the members of International Society for Burn Injury (ISBI), who were invited to complete the survey. Data collection and report was compliant with the the Checklist for Reporting Results of Internet E-Surveys (CHERRIES) Web-survey guidelines. The survey form with multiple-choice questions was divided into 3 parts: a. physician and institutional demographics, b. AKI diagnostic information, c. technical aspects of RRT.

RESULTS

A total of 44 respondents worldwide submitted valuable data in the 2-month period. Of all respondents, 43.2% were from Europe, 30% from North America, 7% from South-East Asia 2.3% from Africa and 18.2% from other regions. 93.1% of participants declare that they use specific definitions to detect AKI, while 11.4% declare the use of renal ultrasonography for AKI diagnosis. CRRT appeared to be the most preferred option by 43.2% of participants, followed by intermittent hemodialysis (25%), and prolonged intermittent RRT (6.8%). The expertise to deliver a modality and the availability of resources were considered important factors when selecting the optimal RRT modality by 20.5% and 29.6% of respondents. The use of specific serum biomarkers for AKI diagnosis are stated by 16% of respondents; 25% of specialists refer to the use of biomarkers of AKI as a criterium for discontinuing the RRT. Femoral vena and right jugular vena were the most frequently used location for RRT temporary catheter placement, 54.6% of respondents declared using ultrasound guidance for catheter placement.

CONCLUSIONS

The majority of burn specialists use specific consensus classifications to detect acute kidney injury. Continuous renal replacement therapy appeared to be the most preferred option, while the expertise to deliver a particular modality and resources availability play a significant role in modality selection. The use of ultrasound and specific biomarkers for AKI evaluation is infrequent in routine clinical practice.

Blood Filters in Children with COVID-19 and AKI: A Review

COVID-19 has challenged the global healthcare system through rapid proliferation and lack of existing treatment resulting in over 180 million cases and 3.8 million deaths since December 2019. Although pediatric patients only comprise 1-2% of diagnosed cases, their incidence of acute kidney injury ranges from 8.2% to 18.2% compared to 49% in adults. Severe infection, initiated by dysregulated host response, can lead to multiorgan failure. In this review, we focus on the use of various blood filters approved for use in pediatric kidney replacement therapy to mitigate adverse effects of severe illness. Therapeutic effects of these blood filters range from cytokine removal (CytoSorb, HA330, HCO/MCO), endotoxin removal (Toraymyxin, CPFA), both cytokine and endotoxin removal (oXiris), and non-specific removal of proteins (PMMA) that have already been established and can be used to mitigate the various effects of the cytokine storm syndrome in COVID-19.

Pediatric acute kidney injury: new advances in the last decade

Pediatric acute kidney injury (AKI) is a frequently missed complication. AKI has a significant impact on both short- and long-term outcomes in children. Within the last decade, there have been major landmark developments in this field of critical care pediatric nephrology. The topic was searched by two independent researchers using Google Scholar and PubMed and related studies published in the last 10 years. The terms used for the search were 'pediatric acute kidney injury,' 'pediatric acute renal failure,' 'pediatric dialysis,' 'biomarkers,' 'nephrotoxins,' 'nephrotoxicity in children,' and 'pediatric critical care nephrology.' We found that AKI is common in critically ill neonates and children. Among the various definitions, the Kidney Disease: Improving Global Outcomes (KDIGO) definition is most commonly used. In addition, it is imperative to risk stratify sick children at admission in the hospital to predict AKI and worse outcomes as this aids in early management. There are now major landmark trials that describe the epidemiology, prevention, and management guidelines in this field and health care professionals need to be aware they should diagnose AKI early. Overall, this review highlights the landmark studies in the last decade and shows that early diagnosis and management of AKI in 'at risk' children can improve outcomes.

Advances in Kidney Replacement Therapy in Infants

Acute kidney injury continues to be a highly occurring disease in the intensive care unit, specifically affecting up to a third of critically ill neonates as per various studies. Although first-line treatments of acute kidney injury are noninvasive, kidney replacement therapy (KRT) is indicated when conservative management modes fail. There are various modalities of KRT which can be used for neonatal populations, including peritoneal dialysis, hemodialysis, and continuous KRT. However, these KRT modalities present their own challenges in this specific patient population Thus, it is the aim of this review to introduce each of these KRT modalities in terms of their challenges, advances, and future directions, with specific emphasis on new technology including the Cardio-Renal Pediatric Emergency Dialysis Machine, Newcastle infant dialysis and ultrafiltration system, and the Aquadex system for ultrafiltration.

Renal Replacement Therapy in Pediatric Acute Kidney Injury

Acute kidney injury (AKI) is common in critically ill children and affects nearly 30-40% of patients admitted to the pediatric intensive care unit (ICU). Even with technological advances in critical care and dialysis, there is a high mortality rate of 66.8% to 90% in ICU patients. Renal replacement therapy (RRT) is often performed to treat patients with AKI. However, for optimal RRT treatment, it is crucial to consider the indications, modes of access, and prescription of each RRT method. Therefore, this review aims to discuss the various modalities of RRT in pediatric patients, which include peritoneal dialysis (PD), hemodialysis (HD), continuous RRT (CRRT), and sustained low-efficiency dialysis (SLED).

Renal replacement therapies for infants and children in the ICU

PURPOSE OF REVIEW

Pediatric acute kidney injury (AKI) in critically ill patients is associated with increased morbidity and mortality. Emerging data support that the incidence of pediatric AKI in the ICU is rising. For children with severe AKI, renal replacement therapy (RRT) can provide a lifesaving supportive therapy. The optimal timing to deliver and modality by which to deliver RRT remain a point of discussion within pediatric (and adult) literature. This review discusses the use of RRT for pediatric patients in the ICU. We discuss the most recent evidence-based methods for RRT with a focus on continuous RRT.

RECENT FINDINGS

The feasibility of dialyzing the smallest infants and more medically complex children in the ICU is dependent on the advancements in dialysis access and circuit technology. At present, data indicate that upward of 27% of children in the ICU develop AKI and 6% require RRT. Newer dialysis modalities including prolonged intermittent hemodialysis and continuous flow peritoneal dialysis as well as newer dialysis technologies such as the smaller volume circuits (e.g., Cardio-Renal Pediatric Dialysis Emergency Machine, Newcastle Infant Dialysis and Ultrafiltration System) have made the provision of dialysis safer and more effective for pediatric patients of a variety of sizes.

SUMMARY

Renal replacement in the ICU requires a multidisciplinary team approach that is facilitated by a pediatric nephrologist in conjunction with intensivists and skilled nursing staff. Although mortality rates for children on dialysis remain high, outcomes are improving with the support of the multidisciplinary team and dialysis technology advancements.

Pediatric Continuous Renal Replacement Therapy (PCRRT) expert committee recommendation on prescribing prolonged intermittent renal replacement therapy (PIRRT) in critically ill children

INTRODUCTION

Recently, prolonged intermittent renal replacement therapies (PIRRT) have emerged as cost-effective alternatives to conventional CRRT and their use in the pediatric population has started to become more prominent. However, there is a lack of consensus guidelines on the use of PIRRT in pediatric patients in an intensive care setting.

METHODS

A literature search was performed on PubMed/Medline, Embase, and Google Scholar in conjunction with medical librarians from both India and the Cleveland Clinic hospital system to find relevant articles. The Pediatric Continuous Renal Replacement Therapy workgroup analyzed all articles for relevancy, proposed recommendations, and graded each recommendation for their strength of evidence.

RESULTS

Of the 60 studies eligible for review, the workgroup considered data from 37 studies to formulate guidelines for the use of PIRRT in children. The guidelines focused on the definition, indications, machines, and prescription of PIRRT.

CONCLUSION

Although the literature on the use of PIRRT in children is limited, the current studies give credence to their benefits and these expert recommendations are a valuable first step in the continued study of PIRRT in the pediatric population.