Timing of initiation of renal replacement therapy in acute kidney injury: an updated meta-analysis of randomized controlled trials

[Emergencies in nephrology]

Emergencies in nephrology are mainly acute life-threatening situations for patients. Furthermore, one needs to consider constellations that are so damaging to the kidneys that the need for permanent dialysis develops within a short period of time. Acute kidney failure as an immediate consequence is categorized using the Acute Kidney Injury Network (AKIN) stages and is pathophysiologically subdivided into pre-, intra- and post-renal. This leads to changes in volume status, acid base and electrolytes, while the terms nephrotic and nephritic describe the amount of kidney damage and help to choose diagnostic steps wisely. Patients that are already undergoing dialysis treatment or have received a kidney transplant are a further specific group in the case of emergencies.

Daily serum phosphate increase as early and reliable indicator of kidney injury in children with leukemia and lymphoma developing tumor lysis syndrome

BACKGROUND

Tumor lysis syndrome (TLS) and its most serious complication, acute kidney injury (AKI) are one of the emergency conditions in onco-hematology. It is difficult to predict the degree of kidney involvement. Therefore, we studied children with leukemia and lymphoma treated in four Hungarian tertiary centers (inpatient university clinics) retrospectively (2006-2016) from a nephrological aspect.

METHOD

Data of 31 pediatric patients were obtained from electronic- and paper-based medical records. Physical status, laboratory test results, treatments, and outcomes were assessed. Patients were analyzed according to both "traditional" TLS groupings, as laboratory TLS or clinical TLS, and nephrological aspect based on pRIFLE classification, as mild or severe AKI.

RESULTS

Significant differences were found between the changes in parameters of phosphate homeostasis and urea levels in both classifications. Compared to age-specific normal phosphate ranges, before the development of TLS, hypophosphatemia was common (19/31 cases), while in the post-TLS period, hyperphosphatemia was observed (26/31 cases) most frequently. The rate of daily change in serum phosphate level was significant in the nephrological subgroups, but peaks of serum phosphate level show only a moderate increase. The calculated cut-off value of daily serum phosphate level increased before AKI was 0.32 mmol/L per ROC analysis for severe TLS-AKI. The 24-h urinalysis data of eight patients revealed transiently increased phosphate excretion only in those patients with TLS in whom serum phosphate was elevated in parallel.

CONCLUSION

Daily serum phosphate level increase can serve as a prognostic factor for the severity of pediatric TLS, as well as predict the severity of kidney involvement. A higher resolution version of the Graphical abstract is available as Supplementary information.

Early versus Late Initiation of Renal Replacement Therapy: Have We Reached the Consensus? An Updated Meta-Analysis

OBJECTIVES

The objective of this study is to compare early versus late/standard initiation of renal replacement therapy (RRT) in patients with acute kidney injury (AKI).

DATA SOURCES

MEDLINE/PubMed, Embase, Google Scholar, Cochrane Central Register of Controlled Trials, and the Cochrane renal group till August 15, 2020.

STUDY SELECTION

Randomized controlled trials (RCTs) comparing early versus late initiation of RRT in patients with AKI were included. The primary outcome measures were all-cause mortality and dialysis dependence on day 90. Secondary outcome measures were length of stay, recovery of renal functions, and adverse events.

DATA EXTRACTION

Two authors independently performed study selection and data extraction using data extraction forms.

DATA SYNTHESIS

A total of 14 RCTs with 5,234 participants were included. Three trials had low risk of bias in all the domains. There was no significant difference in the overall mortality (risk ratio (RR): 0.99; 95% confidence interval (CI): 0.89, 1.10; moderate certainty of evidence), day 30 mortality (RR: 1.0; 95% CI: 0.91, 1.09; high certainty of evidence), day 90 mortality (RR: 1.00; 95% CI: 0.88, 1.13; high certainty of evidence), and ICU mortality (RR: 1.00; 95% CI: 0.90, 1.10; moderate certainty of evidence) between the early versus late RRT. Dialysis dependence on day 90 was significantly higher in the patients assigned to early RRT (RR: 1.55; 95% CI: 1.15, 2.09; moderate certainty of evidence). The treatment-emergent adverse events (hypophosphatemia and hypotension) were significantly higher in the patients assigned to early RRT.

CONCLUSION

There is no added benefit of early initiation of RRT in patient with AKI; this may lead to treatment-emergent adverse events. Delaying the initiation of RRT with close monitoring and initiating RRT for emergent indications should be the acceptable criterion in critical care nephrology. Prospero Registration: CRD42016043092.

The timing of continuous renal replacement therapy initiation in sepsis-associated acute kidney injury in the intensive care unit: the CRTSAKI Study (Continuous RRT Timing in Sepsis-associated AKI in ICU): study protocol for a multicentre, randomised controlled trial

INTRODUCTION

Acute kidney injury (AKI) is one of the most common organ dysfunction in sepsis, and increases the risk of unfavourable outcomes. Renal replacement therapy (RRT) is the predominant treatment for sepsis-associated AKI (SAKI). However, to date, no prospective randomised study has adequately addressed whether initiating RRT earlier will attenuate renal injury and improve the outcome of sepsis. The objective of the trial is to compare the early strategy with delayed strategy on the outcomes in patients with SAKI in the intensive care unit (ICU).

METHODS AND ANALYSIS

This is a large-scale, multicentre, randomised controlled trial about SAKI. In total, 460 patients with sepsis and evidence of AKI stage 2 of Kidney Disease Improving Global Outcomes (KDIGO) will be recruited and equally randomised into the early group and the delay group in a ratio of 1:1. In the early group, continuous RRT (CRRT) will be started immediately after randomisation. In the delay group, CRRT will initiated if at least one of the following criteria was met: stage 3 of KDIGO, severe hyperkalaemia, pulmonary oedema, blood urea nitrogen level higher than 112 mg/dL after randomisation. The primary outcome is overall survival in a 90-day follow-up period (90-day all-cause mortality). Other end points include 28-day, 60-day and 1-year mortality, recovery rate of renal function by day 28 and day 90, ICU and hospital length of stay, the numbers of CRRT-free days, mechanical ventilation-free days and vasopressor-free days, the rate of complications potentially related to CRRT, CRRT-related cost, and concentrations of inflammatory mediators in serum.

ETHICS AND DISSEMINATION

The trial has been approved by the Clinical Research and Application Institutional Review Board of the Second Affiliated Hospital of Guangzhou Medical University (2017-31-ks-01). Participants will be screened and enrolled from patients in the ICU with SAKI by clinicians, with no public advertisement for recruitment. Results will be disseminated in research journals and through conference presentations.

TRIAL REGISTRATION

NCT03175328.

Starting Kidney Replacement Therapy in Critically III Patients with Acute Kidney Injury

Kidney replacement therapy (KRT) is a core organ support in critical care settings. In patients suitable for escalation in support, who develop acute kidney injury (AKI) complications and urgent indications, there is consensus that KRT should be promptly initiated. In the absence of such urgent indications, the optimal timing has been less certain. Current clinical practice guidelines do not present strong recommendations for when to start KRT for patients with AKI in the absence of life-threatening and urgent indications. This article discusses how best to provide KRT to critically ill patients with severe AKI.

Timing of Initiation of Renal Replacement Therapy in Sepsis-Associated Acute Kidney Injury

Sepsis-associated acute kidney injury (SA-AKI) is a major issue in medical, surgical and intensive care settings and is an independent risk factor for increased mortality, as well as hospital length of stay and cost. SA-AKI encompasses a proper pathophysiology where renal and systemic inflammation play an essential role, surpassing the classic concept of acute tubular necrosis. No specific treatment has been defined yet, and renal replacement therapy (RRT) remains the cornerstone supportive therapy for the most severe cases. The timing to start RRT, however, remains controversial, with early and late strategies providing conflicting results. This article provides a comprehensive review on the available evidence on the timing to start RRT in patients with SA-AKI.