Effects of early high-volume continuous venovenous hemofiltration on survival and recovery of renal function in intensive care patients with acute renal failure: a prospective, randomized trial

Kidney Replacement Therapies in Advanced Heart Failure - Timing, Modalities, and Clinical Considerations

Acute kidney dysfunction is commonly encountered in advanced heart failure and carries significant prognostic implications, often leading to poorer outcomes and increased mortality. It can alter the course of decision making for left ventricular assist device (LVAD) and cardiac transplantation candidacy. Kidney replacement therapies (KRT) offer a critical intervention in this context but require careful consideration of timing, various types of KRT modalities, individual patient preferences and circumstances. This review discusses the intricacies of KRT in advanced heart failure, examining how to optimize timing and choose among the various KRT modalities. It also provides a detailed discussion on the unique clinical scenarios that clinicians may face when treating this vulnerable patient group.

Continuous Renal Replacement Therapy and Mortality in Critically Ill Obese Adults

IMPORTANCE

The outcomes of critically ill adults with obesity on continuous renal replacement therapy (CRRT) are poorly characterized. The impact of CRRT dose on these outcomes is uncertain.

OBJECTIVES

This study aimed to determine if obesity conferred a survival advantage for critically ill adults with acute kidney injury (AKI) on CRRT. Secondarily, we evaluated whether the dose of CRRT predicted mortality in this population.

DESIGN SETTING AND PARTICIPANTS

A retrospective, observational cohort study performed at an academic medical center in Minnesota. The study population included critically ill adults with AKI managed with CRRT.

MAIN OUTCOMES AND MEASURES

The primary outcome of 30-day mortality was compared between obese (body mass index [BMI] ≥ 30 kg/m2) and nonobese (BMI < 30 kg/m2) patients. Multivariable regression assessed was used to assess CRRT dose as a predictor of outcomes. An analysis included dose indexed according to actual body weight (ABW), adjusted body weight (AdjBW), or ideal body weight (IBW).

RESULTS

Among 1033 included patients, the median (interquartile range) BMI was 26 kg/m2 (23-28 kg/m2) in the nonobese group and 36 kg/m2 (32-41 kg/m2) in the obese group. Mortality was similar between groups at 30 days (54% vs. 48%; p = 0.06) but lower in the obese group at 90 days (62% vs. 55%; p = 0.02). CRRT dose predicted an increase in mortality when indexed according to ABW or AdjBW (hazard ratio [HR], 1.2-1.16) but not IBW (HR, 1.04).

CONCLUSIONS AND RELEVANCE

In critically ill adults with AKI requiring CRRT, short-term mortality appeared lower in obese patients compared with nonobese patients. Among weight calculations, IBW appears to be preferred to promote safe CRRT dosing in obese patients.

Vancomycin dosing in high-intensity continuous renal replacement therapy: A retrospective cohort study

INTRODUCTION

An inverse relationship exists between vancomycin serum concentrations and the intensity of continuous renal replacement therapy (CRRT), reflected through the dialysate flow rate (DFR). There remains a lack of evidence to guide initial vancomycin dosing in the setting of high-intensity CRRT (i.e., DFR >30 mL/kg/h). Additionally, recommendations for pharmacokinetic monitoring of vancomycin have transitioned from a trough-based to area under the curve (AUC)-based dosing strategy to optimize efficacy and safety. Therefore, an improved understanding of the impact of CRRT intensity on AUC/MIC (minimum inhibitory concentration) has the potential to enhance vancomycin dosing in this patient population.

OBJECTIVES

The goal of this study is to evaluate current vancomycin dosing strategies and achievement of pharmacokinetic targets in patients on high-intensity CRRT.

METHODS

This was a single-center, retrospective cohort study of adult critically ill patients admitted to Houston Methodist Hospital between May 2019 and October 2021 and received vancomycin therapy while on high-intensity CRRT. High-intensity CRRT was defined by a DFR that was both ≥3 L/h and >30 mL/kg/h. Depending on the initial vancomycin dosing strategy, patients were stratified into either the traditional (15 mg/kg/day) or enhanced (≥15 mg/kg/day) dosing group. The primary outcome was the percent of patients who attained steady-state AUC24 /MIC ≥400 mg*h/L at the first obtained vancomycin level in the enhanced group compared with the traditional group.

RESULTS

A total of 125 patients were included in the final analysis, 56 in the traditional and 69 in the enhanced dosing group. The primary end point occurred in 74% and 54% of patients in the enhanced and traditional dosing groups, respectively (p = 0.029). Therapeutic vancomycin trough levels (10-20 μg/mL) were more commonly achieved in the enhanced dosing group compared with the traditional dosing group (66.7% vs. 45%, p = 0.013). As DFR rose, increasingly higher doses of vancomycin, up to 27 mg/kg/day, were required to achieve the therapeutic targets.

CONCLUSION

This is the first study to evaluate the influence of variable CRRT intensities on vancomycin AUC/MIC. Our findings suggest that vancomycin doses of ≥15 mg/kg/day are needed to achieve early therapeutic targets in patients on high-intensity CRRT.

Extracorporeal blood purification therapies for sepsis-associated acute kidney injury in critically ill patients: expert opinion from the SIAARTI-SIN joint commission

Sepsis-Associated Acute Kidney Injury is a life-threatening condition leading to high morbidity and mortality in critically ill patients admitted to the intensive care unit. Over the past decades, several extracorporeal blood purification therapies have been developed for both sepsis and sepsis-associated acute kidney injury management. Despite the widespread use of extracorporeal blood purification therapies in clinical practice, it is still unclear when to start this kind of treatment and how to define its efficacy. Indeed, several questions on sepsis-associated acute kidney injury and extracorporeal blood purification therapy still remain unresolved, including the indications and timing of renal replacement therapy in patients with septic vs. non-septic acute kidney injury, the optimal dialysis dose for renal replacement therapy modalities in sepsis-associated acute kidney injury patients, and the rationale for using extracorporeal blood purification therapies in septic patients without acute kidney injury. Moreover, the development of novel extracorporeal blood purification therapies, including those based on the use of adsorption devices, raised the attention of the scientific community both on the clearance of specific mediators released by microorganisms and by injured cells and potentially involved in the pathogenic mechanisms of organ dysfunction including sepsis-associated acute kidney injury, and on antibiotic removal. Based on these considerations, the joint commission of the Italian Society of Anesthesiology and Critical Care (SIAARTI) and the Italian Society of Nephrology (SIN) herein addressed some of these issues, proposed some recommendations for clinical practice and developed a common framework for future clinical research in this field.

Evaluation of the registry DIALYREG for the assessment of continuous renal replacement techniques in the critically ill patient

Continuous renal replacement techniques (CRRT) can induce complications and monitoring is crucial to ensure patient safety. We designed a prospective multicenter observational and descriptive study using the DIALYREG registry, an online database located on a REDCap web-based platform that allows real-time data analysis. Our main objective was to identify CRRT-related complications in our intensive care units (ICUs) and implement security measures accordingly. From January 2019 to December 2020, we included 323 patients with admission diagnoses of medical illness (54%), sepsis (24%), postoperative care (20%), and trauma (2%). CRRT indications were homeostasis (42%), oliguria (26%), fluid overload (15%), and hemodynamic optimization (13%). The median initial therapy dose was 30 ml/kg/h (IQR 25-40), and dynamic adjustment was performed in 61% of the treatments. Sets were anticoagulated with heparin (40%), citrate (38%) or no anticoagulation (22%). Citrate anticoagulation had several advantages: more frequent dynamic CRRT dose adjustment (77% vs. 58% with heparin and 56% without anticoagulation, p < 0.05), longer duration of set (median of 55 h, IQR 24-72 vs. 23 h, IQR 12-48 with heparin and 12 h, IQR 12-31 without anticoagulation, p < 0.05), less clotting of the set (26% vs. 46.7% with heparin, p < 0.05), and lower incidence of hypophosphatemia (1% citrate vs. 6% with heparin and 5% without anticoagulation). It was also safe and effective in subgroup analysis of patients with liver disease or sepsis. The main global complications were hypothermia (16%), hypophosphatemia (13%) and metabolic acidosis (10%). Weaning of the therapy was achieved through early discontinuation (56%), nocturnal therapy transition (26%) and progressive SLED (18%). 52% of the patients were discharged from the hospital, while 43% died in the ICU and 5% died during hospitalization. We can conclude that the DIALYREG registry is a feasible tool for real-time control of CRRT in our ICU.

Timing of initiation of renal replacement therapy for patients with acute kidney injury: A meta-analysis of RCTs

PURPOSE

To assess the effects of delayed versus early renal replacement therapy (RRT) initiation for patients with AKI.

METHODS

Related RCTs of RRT initiated at different times published on PubMed, Web of Science, Embase, and Cochrane Library were searched.

RESULTS

Fifteen RCTs studies with 5395 patients were included. The results showed that the 28-day mortality (RR 1.01; 95% CI 0.94 ~ 1.08; p = 0.80), 60-day mortality (RR 1.00; 95% CI 0.91 ~ 1.11; p = 0.93), 90-day mortality (RR 1.01; 95% CI 0.94 ~ 1.08; p = 0.80), dialysis dependence among survivors (RR 0.67; 95% CI 0.40 ~ 1.13; p = 0.13), length of ICU stay (RR -1.32; 95% CI -3.26 ~ 0.62; p = 0.18) and length of hospital stay among survivors(RR -0.98; 95% CI -2.89 ~ 0.92; p = 0.31) were not significantly different between the two groups. In addition, early initiation of RRT increases the incidence of hypotension (RR 1.42, 95% CI 1.23 ~ 1.63; p < 0.00001) and infectious (RR 1.36; 95% CI 1.03 ~ 1.80; p = 0.03) events.

CONCLUSION

Early initiation of RRT cannot improve the prognosis and benefit patients.

Indications for and Timing of Initiation of KRT

KRT is considered for patients with severe AKI and associated complications. The exact indications for initiating KRT have been debated for decades. There is a general consensus that KRT should be considered in patients with AKI and medically refractory complications ("urgent indications"). "Relative indications" are more common but defined with less precision. In this review, we summarize the latest evidence from recent landmark clinical trials, discuss strategies to anticipate the need for KRT in individual patients, and propose an algorithm for decision making. We emphasize that the decision to consider KRT should be made in conjunction with other forms of organ support therapies and important nonkidney factors, including the patient's preferences and overall goals of care. We also suggest future research to differentiate patients who benefit from timely initiation of KRT from those with imminent recovery of kidney function. Until then, efforts are needed to optimize the initiation and delivery of KRT in routine clinical practice, to minimize nonessential variation, and to ensure that patients with persistent AKI or progressive organ failure affected by AKI receive KRT in a timely manner.

Timing of kidney replacement therapy initiation for acute kidney injury

BACKGROUND

Acute kidney injury (AKI) is a common condition among patients in intensive care units (ICUs) and is associated with high numbers of deaths. Kidney replacement therapy (KRT) is a blood purification technique used to treat the most severe forms of AKI. The optimal time to initiate KRT so as to improve clinical outcomes remains uncertain. This is an update of a review first published in 2018. This review complements another Cochrane review by the same authors: Intensity of continuous renal replacement therapy for acute kidney injury.

OBJECTIVES

To assess the effects of different timing (early and standard) of KRT initiation on death and recovery of kidney function in critically ill patients with AKI.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant's Specialised Register to 4 August 2022 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, EMBASE, conference proceedings, the International Clinical Trials Register, ClinicalTrials and LILACS to 1 August 2022.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs). We included all patients with AKI in the ICU regardless of age, comparing early versus standard KRT initiation. For safety and cost outcomes, we planned to include cohort studies and non-RCTs.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two authors. The random-effects model was used, and results were reported as risk ratios(RR) for dichotomous outcomes and mean difference(MD) for continuous outcomes, with 95% confidence intervals (CI).

MAIN RESULTS

We included 12 studies enrolling 4880 participants. Overall, most domains were assessed as being at low or unclear risk of bias. Compared to standard treatment, early KRT initiation may have little to no difference on the risk of death at day 30 (12 studies, 4826 participants: RR 0.97,95% CI 0.87 to 1.09; I²= 29%; low certainty evidence), and death after 30 days (7 studies, 4534 participants: RR 0.99, 95% CI 0.92 to 1.07; I² = 6%; moderate certainty evidence). Early KRT initiation may make little or no difference to the risk of death or non-recovery of kidney function at 90 days (6 studies, 4011 participants: RR 0.91, 95% CI 0.74 to 1.11; I² = 66%; low certainty evidence); CIs included both benefits and harms. Low certainty evidence showed early KRT initiation may make little or no difference to the number of patients who were free from KRT (10 studies, 4717 participants: RR 1.07, 95% CI 0.94 to1.22; I² = 55%) and recovery of kidney function among survivors who were free from KRT after day 30 (10 studies, 2510 participants: RR 1.02, 95% CI 0.97 to 1.07; I² = 69%) compared to standard treatment. High certainty evidence showed early KRT initiation increased the risk of hypophosphataemia (1 study, 2927 participants: RR 1.80, 95% CI 1.33 to 2.44), hypotension (5 studies, 3864 participants: RR 1.54, 95% CI 1.29 to 1.85; I² = 0%), cardiac-rhythm disorder (6 studies, 4483 participants: RR 1.35, 95% CI 1.04 to 1.75; I² = 16%), and infection (5 studies, 4252 participants: RR 1.33, 95% CI 1.00 to 1.77; I² = 0%); however, it is uncertain whether early KRT initiation increases or reduces the number of patients who experienced any adverse events (5 studies, 3983 participants: RR 1.23, 95% CI 0.90 to 1.68; I² = 91%; very low certainty evidence). Moderate certainty evidence showed early KRT initiation probably reduces the number of days in hospital (7 studies, 4589 participants: MD-2.45 days, 95% CI -4.75 to -0.14; I² = 10%) and length of stay in ICU (5 studies, 4240 participants: MD -1.01 days, 95% CI -1.60 to -0.42; I² = 0%).

AUTHORS' CONCLUSIONS

Based on mainly low to moderate certainty of the evidence, early KRT has no beneficial effect on death and may increase the recovery of kidney function. Earlier KRT probably reduces the length of ICU and hospital stay but increases the risk of adverse events. Further adequate-powered RCTs using robust and validated tools that complement clinical judgement are needed to define the optimal time of KRT in critical patients with AKI in order to improve their outcomes. The surgical AKI population should be considered in future research.

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.

Accelerated-strategy renal replacement therapy for critically ill patients: A systematic review and meta-analysis

BACKGROUND

The aim of this study was to investigate the clinical effect and safety of accelerated-strategy initiation of renal replacement therapy (RRT) in critically ill patients.

METHODS

PubMed, Embase, OVID, EBSCO, and the Cochrane Library databases were searched for relevant articles from inception to December 30, 2020. Only RCTs that compared the clinical efficacy and safety between accelerated-strategy RRT and standard-strategy RRT among critically ill adult patients with acute kidney injury (AKI) were included. The primary outcome was 28-day mortality.

RESULTS

A total of 5279 patients in 12 RCTs were included in this meta-analysis. The 28-day mortality rates of patients treated with accelerated and standard RRT were 37.3% (969/2596) and 37.9% (976/2573), respectively. No significant difference was observed between the groups (OR, 0.92; 95% CI, 0.70-1.12; I2 = 60%). The recovery rates of renal function were 54.5% and 52.5% in the accelerated- and standard-RRT groups, respectively, with no significant difference (OR, 1.03; 95% CI, 0.89-1.19; I2 = 56%). The rate of RRT dependency was similar in the accelerated- and standard-RRT strategies (6.7% vs 5.0%; OR, 1.11; 95% CI, 0.71-1.72; I2 = 20%). The accelerated-RRT group displayed higher risks of hypotension, catheter-related infection, and hypophosphatemia than the standard-RRT group (hypotension: OR, 1.26; 95% CI, 1.10-1.45; I2 = 36%; catheter-related infection: OR, 1.90; 95% CI, 1.17-3.09; I2 = 0%; hypophosphatemia: OR, 2.11; 95% CI, 1.43-3.15; I2 = 67%).

CONCLUSIONS

Accelerated RRT does not reduce the risk of death and does not improve the recovery of kidney function among critically ill patients with AKI. In contrast, an increased risk of adverse events was observed in patients receiving accelerated RRT. However, these findings were based on low quality of evidence. Further large-scale RCTs is warranted.

The impact of early versus late initiation of renal replacement therapy in critically ill patients with acute kidney injury on mortality and clinical outcomes: a meta-analysis

Background

Renal replacement therapy (RRT) is essential in the presence of life-threatening complications associated with acute kidney injury (AKI). In the absence of urgent indications, the optimal timing for RRT initiation is still under debate. This meta-analysis aims to compare the benefits between early and late RRT initiation strategies in critically ill patients with AKI.

Methods

Studies were obtained from three databases [Medical Literature Analysis and Retrieval System Online (MEDLINE), Cochrane Central Register of Controlled Trials (CENTRAL) and Scopus], searched from inception to May 2021. The selected primary outcome was 28-day mortality. Secondary outcomes included overall mortality, recovery of renal function (RRF) and RRT-associated adverse events. A random-effects model was used for summary measures. Heterogeneity was assessed through Cochrane I² test statistics. Potential sources of heterogeneity for the primary outcome were sought using sensitivity analyses. Further subgroup analyses were conducted based on RRT modality and study population.

Results

A total of 13 randomized controlled trials including 5193 participants were analysed. No significant differences were found between early and late RRT initiation regarding 28-day mortality [risk ratio (RR) 1.00; 95% confidence interval (CI) 0.89–1.12, I² = 30%], overall mortality (RR 1.00; 95% CI 0.90–1.12, I² = 42%) and RRF (RR 1.02; 95% CI 0.92–1.13, I² = 53%). However, early RRT initiation was associated with a significantly higher incidence of hypotensive (RR 1.34; 95% CI 1.17–1.53, I² = 6%) and infectious events (RR 1.83; 95% CI 1.11–3.02, I² = 0%).

Conclusions

Early RRT initiation does not improve the 28-day and overall mortality, nor the likelihood of RRF, and increases the risk for RRT-associated adverse events, namely hypotension and infection.

Early versus Delayed Strategies for Renal Replacement Therapy Initiation in Adult Patients with Severe Acute Kidney Injury Complicating Septic Shock: A Systematic Review and Meta-analysis

Sepsis-associated acute kidney injury (AKI) is a frequent complication in hospitalized patients and is associated with significant morbidity and mortality. Renal replacement therapy (RRT) is used to manage AKI. The optimal timing of starting RRT in patients with AKI is still uncertain. This study is aimed to assess the effect of different timing strategies of RRT (early vs. standard) on mortality and dependence on dialysis in severe AKI complicating septic shock. A systematic review was conducted using the Ovid Medline database, trial registries, and manual searches of key journals from January 2000 to October 2020. Appropriate outcomes were pooled and analyzed via a meta-analysis. Only randomized controlled trials (RCTs) were included to compare between the early vs. delayed strategies of RRT. The inverse generic method was used, and the data were pooled using random effects. Five studies were included in this review, with 4329 participants. Overall, most domains were assessed as low-risk or with some concerns about the risk of bias. Compared with standard therapy, early initiation probably results in little or no difference regarding death, and may also result in no or little difference in independence on dialysis. The early strategy may result in a slight increase in adverse events. Compared with the standard strategy, earlier RRT initiation may slightly reduce the length of hospital stay. Further RCTs are needed to define the optimal timing of RRT initiation in this population.

Accelerated versus watchful waiting strategy of kidney replacement therapy for acute kidney injury: a systematic review and meta-analysis of randomized clinical trials

Background

Critically ill patients with severe acute kidney injury (AKI) requiring kidney replacement therapy (KRT) have a grim prognosis. Recently, multiple studies focused on the impact of KRT initiation time [i.e., accelerated versus watchful waiting KRT initiation (WWS-KRT)] on patient outcomes. We aim to review the results of all related clinical trials.

Methods

In this systematic review, we searched all relevant randomized clinical trials from January 2000 to April 2021. We assessed the impacts of accelerated versus WWS-KRT on KRT dependence, KRT-free days, mortality and adverse events, including hypotension, infection, arrhythmia and bleeding. We rated the certainty of evidence according to Cochrane methods and the GRADE approach.

Results

A total of 4932 critically ill patients with AKI from 10 randomized clinical trials were included in this analysis. The overall 28-day mortality rate was 38.5%. The 28-day KRT-dependence rate was 13.0%. The overall incident of KRT in the accelerated group was 97.4% and 62.8% in the WWS-KRT group. KRT in the accelerated group started 36.7 h earlier than the WWS-KRT group. The two groups had similar risks of 28-day [pooled log odds ratio (OR) 1.001, P = 0.982] and 90-day (OR 0.999, P = 0.991) mortality rates. The accelerated group had a significantly higher risk of 90-day KRT dependence (OR 1.589, P = 0.007), hypotension (OR 1.687, P < 0.001) and infection (OR 1.38, P = 0.04) compared with the WWS-KRT group.

Conclusions

This meta-analysis revealed that accelerated KRT leads to a higher probability of 90-day KRT dependence and dialysis-related complications without any impact on mortality rate when compared with WWS-KRT. Therefore, we suggest the WWS-KRT strategy for critically ill patients.

Disease Severity Determines Timing of Initiating Continuous Renal Replacement Therapies: A Systematic Review and Meta-Analysis

Background: Timing of initiating continuous renal replacement therapies (CRRTs) among the patients with acute kidney injury (AKI) in intensive care units (ICU) has been discussed over decades, but the definition of early and late CRRT initiation is still unclear. Methods: The English language randomized controlled trials (RCTs) and cohort studies were searched through MEDLINE, EMBASE, and Cochrane Library on July 19, 2019, by the two researchers independently. The study characteristics; early and late definitions; outcomes, such as all-cause, in-hospital, 28- or 30-, 60-, 90-day mortality; and renal recovery were extracted from the 18 eligible studies. Pooled relative risk ratios (RRs) and 95% CIs were estimated with the fixed effects model and random effects model as appropriate. This study is registered with PROSPERO (CRD 42020158653). Results: Eighteen studies including 3,914 patients showed benefit in earlier CRRT (n = 1,882) over later CRRT (n = 2,032) in all-cause mortality (RR 0.78, 95% CI 0.66-0.92), in-hospital mortality (RR 0.81, 95% CI 0.67-0.99), and 28- or 30-day mortality (RR 0.81, 95% CI 0.74-0.88), but in 60- and 90-day mortalities, no significant benefit was observed. The subgroup analysis showed significant benefit in the disease-severity-based subgroups on early CRRT initiation in terms of in-hospital mortality and 28- or 30-day mortality rather than the time-based subgroups. Moreover, early CRRT was found to have beneficial effects on renal recovery after CRRT (RR 1.21, 95% CI 1.01-1.45). Conclusions: Overall, compared with late CRRT, early CRRT is beneficial for short-term survival and renal recovery, especially when the timing was defined based on the disease severity. CRRT initiation on Acute Kidney Injury Network (AKIN) stage 1 or Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease (RIFLE)-Risk or less may lead to a better prognosis.

Acute kidney injury in cardiogenic shock: A comprehensive review

Acute kidney injury (AKI) is an ominous predictor of mortality in cardiogenic shock. The present review examines the pathophysiology of AKI in cardiogenic shock (CS), summarizes the pertinent literature including the diagnostic criteria/definitions for AKI and possible role of biomarkers, and identifies risk factors and possible therapeutic interventions for AKI in CS. Our review finds that AKI is common in patients with CS and is associated with increased morbidity and mortality. Urinary biomarkers of renal tubular injury appear more sensitive for detection of AKI but have yet to be incorporated into daily practice. Emerging data would suggest vasopressor choices, mechanical circulatory support, and renal replacement therapy may have important therapeutic roles in the management of CS.

Drug dosing considerations in continuous renal replacement therapy

Acute kidney injury (AKI) is a common complication in critically ill patients, which is associated with increased in-hospital mortality. Delivering effective antibiotics to treat patients with sepsis receiving continuous renal replacement therapy (RRT) is complicated by variability in pharmacokinetics, dialysis delivery, lack of primary literature, and therapeutic drug monitoring. Pharmacokinetic alterations include changes in absorption, distribution, protein binding (PB), metabolism, and renal elimination. Drug absorption may be significantly changed due to alterations in gastric pH, perfusion, gastrointestinal motility, and intestinal atrophy. Volume of distribution for hydrophilic drugs may be increased due to volume overload. Estimation of renal clearance is challenged by the effective delivery of RRT. Drug characteristics such as PB, volume of distribution, and molecular weight impact removal of the drug by RRT. The totality of these alterations leads to reduced exposure. Despite our best knowledge, therapeutic drug monitoring of patients receiving continuous RRT demonstrates wide variability in antimicrobial concentrations, highlighting the need for expanded monitoring of all drugs. This review article will focus on changes in drug pharmacokinetics in AKI and dosing considerations to attain antibiotic pharmacodynamic targets in critically ill patients receiving continuous RRT.

Lung Ultrasound: A "Biomarker" for Fluid Overload?

Fluid overload is associated with poor outcomes in patients with acute kidney injury as well as end-stage kidney disease. Lung ultrasound (LUS) has been used in many different settings and specialties including the emergency department, intensive care unit, trauma, cardiology, and nephrology. Although LUS has been a valuable tool in assessing pulmonary congestion, LUS findings may not always be pathognomonic for pulmonary congestion. Furthermore, the feasibility of doing an extensive LUS examination as has been done in research studies may be hard to implement within the clinical setting. This review will go over the use of LUS to evaluate for fluid overload, compare LUS with other markers of fluid overload, review limitations of LUS, and suggest potential future directions in the use of LUS in nephrology.

CRRT prescription and delivery of dose

Continuous renal replacement therapy (CRRT) is the preferred modality of extracorporeal renal support for critically ill patients with acute kidney injury (AKI). The dose of CRRT is reported as effluent flow in ml/kg body weight per hour (ml/kg/h). Solid evidence supports that the delivered CRRT effluent dose for critically ill patients with AKI should be 20-25 ml/kg/h on average. To account for treatment interruptions and the natural decline in filter efficiency over time, it is recommended to prescribe 25-30 ml/kg/h of effluent dose. However, transient higher doses of CRRT in specific clinical scenarios may be needed to accommodate specific solute control needs of a particular patient at a given time. Consequently, there should be consideration of the potential adverse consequences of non-selective clearance such as undesired antimicrobials and nutrients removal. In this manuscript, we provide a summary of evidence related to CRRT dose, practical aspects for its calculation at the time of prescribing CRRT, and considerations for addressing the expected gap between prescribed and delivered CRRT dose. We also provide a framework for monitoring and implementation of CRRT dose as a quality indicator of CRRT delivery.

Time to Initiation of Renal Replacement Therapy Among Critically Ill Patients With Acute Kidney Injury: A Current Systematic Review and Meta-Analysis

OBJECTIVES

The optimal time to initiate renal replacement therapy in critically ill patients with acute kidney injury is controversial. We investigated the effect of such earlier versus later initiation of renal replacement therapy on the primary outcome of 28-day mortality and other patient-centered secondary outcomes.

DESIGN

We searched MEDLINE (via PubMed), EMBASE, and Cochrane databases to July 17, 2020, and included randomized controlled trials comparing earlier versus later renal replacement therapy.

SETTING

Multiple centers involved in eight trials.

PATIENTS

Total of 4,588 trial participants.

INTERVENTION

Two independents investigators screened and extracted data using a predefined form. We selected randomized controlled trials in critically ill adult patients with acute kidney injury and compared of earlier versus later initiation of renal replacement therapy regardless of modality.

MEASUREMENTS AND MAIN RESULTS

Overall, 28-day mortality was similar between earlier and later renal replacement therapy initiation (38.43% vs 38.06%, respectively; risk ratio, 1.01; [95% CI, 0.94-1.09]; I2 = 0%). Earlier renal replacement therapy, however, shortened hospital length of stay (mean difference, -2.14 d; [95% CI, -4.13 to -0.14]) and ICU length of stay (mean difference, -1.18 d; [95% CI, -1.95 to -0.42]). In contrast, later renal replacement therapy decreased the use of renal replacement therapy (relative risk, 0.69; [95% CI, 0.58-0.82]) and lowered the risk of catheter-related blood stream infection (risk ratio, 0.50, [95% CI, 0.29-0.86). Among survivors, renal replacement therapy dependence at day 28 was similar between earlier and later renal replacement therapy initiation (risk ratio, 0.98; [95% CI, 0.66-1.40]).

CONCLUSIONS

Earlier or later initiation of renal replacement therapy did not affect mortality. However, earlier renal replacement therapy was associated with significantly shorter ICU and hospital length of stay, whereas later renal replacement therapy was associated with decreased use of renal replacement therapy and decreased risk of catheter-related blood stream infection. These findings can be used to guide the management of critically ill patients with acute kidney injury.

Timing of kidney replacement therapy initiation in acute kidney injury

PURPOSE OF REVIEW

Over the past 5 years, four major randomized controlled trials were published informing our practice on the optimal timing for kidney replacement therapy (KRT) initiation in critically ill patients with acute kidney injury (AKI). In this review, we summarize the main findings of these trails and discuss the knowledge gaps that still need to be addressed.

RECENT FINDINGS

Four recent trials compared early versus delayed initiation of KRT in critically ill patients with acute kidney injury. Though each trial had unique design features, the three largest trials showed that earlier initiation of KRT did not reduce all-cause mortality.

SUMMARY

A preemptive strategy for initiation of kidney replacement therapy does not confer better survival in critically ill patients with severe AKI. However, early initiation of KRT was associated with a greater risk of iatrogenic complications and one trial showed a higher risk of persistent dialysis dependence. In the absence of absolute indications for KRT, clinicians should defer KRT initiation in patients with AKI. Further research is needed to examine the safety of prolonged KRT deferral and identify markers of fluid overload that may serve to trigger KRT initiation.

Renal replacement therapy in critically ill patients with acute kidney injury: 2020 nephrologist's perspective

Renal replacement therapies (RRT) as support for acute kidney injury in critically ill patients have become a routine and essential practice in their management, resulting in the widespread use of various techniques among these patients, such as intermittent hemodialysis (IHD), extended hemodialysis and continuous RRT (CRRT). In this review we aim to summarize current evidence of indication, choice of modality, timing of initiation, dosing and technical aspects of RRT. We carried out a narrative review based on guidelines, consensus documents by main working groups and the latest relevant clinical trials on RRT in the critically ill. We did not find enough evidence of any RRT modality having superior benefits in terms of patient survival, length of intensive care unit/hospital stay or renal outcomes among critically ill patients, in spite of optimization of clinical indication, modality, timing of initiation and intensity of initial therapy. This is still a controverted matter, since only early start of high-flux CRRT has been proven beneficial over IHD among hemodynamically unstable postoperative patients. Our objective is to portrait current RRT practices in multidisciplinary management of critically ill patients by intensive care and nephrology professionals. Implication of a nephrologist in the assessment of hemodynamic status, coexisting medical conditions, renal outcome expectations and management of resources could potentially have benefits at the time of RRT selection and troubleshooting.

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.

Dose of Continuous Renal Replacement Therapy in Critically Ill Patients: A Bona Fide Quality Indicator

Acute kidney injury (AKI) is common in critically ill patients, and renal replacement therapy (RRT) constitutes an important aspect of acute management during critical illness. Continuous RRT (CRRT) is frequently utilized in intensive care unit settings, particularly in patients with severe AKI, fluid overload, and hemodynamic instability. The main goal of CRRT is to timely optimize solute control, acid-base, and volume status. Total effluent dose of CRRT is a deliverable that depends on multiple factors and therefore should be systematically monitored (prescribed vs. delivered) and iteratively adjusted in a sustainable mode. In this manuscript, we review current evidence of CRRT dosing and provide recommendations for its implementation as a quality indicator of CRRT delivery.

Timing of renal replacement therapy for patients with acute kidney injury: A systematic review and meta-analysis

BACKGROUND

Acute kidney injury is associated with high mortality, and the optimal time to start renal replacement therapy for acute kidney injury is unknown despite several randomised controlled trials on the subject. We performed a systematic review and meta-analysis to assess the effect of earlier initiation of renal replacement therapy for acute kidney injury on mortality and reported secondary outcomes.

METHODS

All literature in databases EMBASE, MEDLINE and CENTRAL was searched from January 1970 to March 2019 using terms related to renal replacement therapy, timing and randomised controlled trials. All randomised controlled trials with 25 or more adult participants suffering from acute kidney injury comparing timing of renal replacement therapy were included. The results of the selected studies were pooled and expressed in terms of risk ratios (RR) and 95% confidence intervals (95% CI) using a random effects model.

RESULTS

A total of 7008 records were identified; 94 were selected for full text review of which 10 were included in the final meta-analysis. The 10 studies comprised 1956 participants (989 'early' group; 967 'late' group) with 918 total deaths; the analysis demonstrated no significant differences between the 'early' and 'late' renal replacement therapy groups (RR = 0.98 (95% CI = 0.84, 1.15)) for mortality. No significant differences between groups were evident for period-wise mortality; dialysis dependence; recovery of renal function; length of intensive care unit or hospital stay; or number of renal replacement therapies, mechanical ventilation and vasopressor-free days.

CONCLUSIONS

Current evidence does not support the use of early renal replacement therapy for patients with acute kidney injury. Data from ongoing and future randomised controlled trials are required to strengthen the evidence base in the area.

Timing of renal replacement therapy initiation for acute kidney injury in critically ill patients: a systematic review of randomized clinical trials with meta-analysis and trial sequential analysis

Background

Acute kidney injury (AKI) is a common serious complication in critically ill patients. AKI occurs in up to 50% patients in intensive care unit (ICU), with poor clinical prognosis. Renal replacement therapy (RRT) has been widely used in critically ill patients with AKI. However, in patients without urgent indications such as acute pulmonary edema, severe acidosis, and severe hyperkalemia, the optimal timing of RRT initiation is still under debate. We conducted this systematic review of randomized clinical trials (RCTs) with meta-analysis and trial sequential analysis (TSA) to compare the effects of early RRT initiation versus delayed RRT initiation.

Methods

We searched databases (PubMed, EMBASE and Cochrane Library) from inception through to July 20, 2020, to identify eligible RCTs. The primary outcome was 28-day mortality. Two authors extracted the data independently. When the I² values < 25%, we used fixed-effect mode. Otherwise, the random effects model was used as appropriate. TSA was performed to control the risk of random errors and assess whether the results in our meta-analysis were conclusive.

Results

Eleven studies involving 5086 patients were identified. Two studies included patients with sepsis, one study included patients with shock after cardiac surgery, and eight others included mixed populations. The criteria for the initiation of RRT, the definition of AKI, and RRT modalities existed great variations among the studies. The median time of RRT initiation across studies ranged from 2 to 7.6 h in the early RRT group and 21 to 57 h in the delayed RRT group. The pooled results showed that early initiation of RRT could not decrease 28-day all-cause mortality compared with delayed RRT (RR 1.01; 95% CI 0.94–1.09; P = 0.77; I² = 0%). TSA result showed that the required information size was 2949. The cumulative Z curve crossed the futility boundary and reached the required information size. In addition, early initiation of RRT could lead to unnecessary RRT exposure in some patients and was associated with a higher incidence of hypotension (RR 1.42; 95% CI 1.23–1.63; P < 0.00001; I² = 8%) and RRT-associated infection events (RR 1.34; 95% CI 1.01–1.78; P = 0.04; I² = 0%).

Conclusions

This meta-analysis suggested that early initiation of RRT was not associated with survival benefit in critically ill patients with AKI. In addition, early initiation of RRT could lead to unnecessary RRT exposure in some patients, resulting in a waste of health resources and a higher incidence of RRT-associated adverse events. Maybe, only critically ill patients with a clear and hard indication, such as severe acidosis, pulmonary edema, and hyperkalemia, could benefit from early initiation of RRT.

Accelerated versus standard initiation of renal replacement therapy for critically ill patients with acute kidney injury: a systematic review and meta-analysis of RCT studies

BACKGROUND

Acute kidney injury (AKI) is a common yet possibly fatal complication among critically ill patients in intensive care units (ICU). Although renal replacement therapy (RRT) is an important supportive management for severe AKI patients, the optimal timing of RRT initiation for these patients is still unclear.

METHODS

In this systematic review, we searched all relevant randomized controlled trials (RCTs) that directly compared accelerated with standard initiation of RRT from PUBMED, MEDLINE, EMBASE, and Cnki.net published prior to July, 20, 2020. We extracted study characteristics and outcomes of being free of dialysis, dialysis dependence and mortality. We rated the certainty of evidence according to Cochrane methods and the GRADE approach.

RESULTS

We identified 56 published relevant studies from 1071 screened abstracts. Ten RCTs with 4753 critically ill AKI patients in intensive care unit (ICU) were included in this meta-analysis. In our study, accelerated and standard RRT group were not associated with all-cause mortality (log odds-ratio [OR]: - 0.04, 95% confidence intervals [CI] - 0.16 to 0.07, p = 0.46) and free of dialysis (log OR: - 0.03, 95% CI - 0.14 to 0.09, p = 0.65). In the subgroup analyses, accelerated RRT group was significantly associated with lower risk of all-cause mortality in the surgical ICU and for those who received continuous renal replacement therapy (CRRT). In addition, patients in these two subgroups had higher chances of being eventually dialysis-free. However, accelerated initiation of RRT augmented the risk of dialysis dependence in the subgroups of patients treated with non-CRRT modality and whose Sequential Organ Failure Assessment (SOFA) score were more than 11.

CONCLUSIONS

In this meta-analysis, critically ill patients with severe AKI would benefit from accelerated RRT initiation regarding all-cause mortality and being eventually free of dialysis only if they were surgical ICU patients or if they underwent CRRT treatment. However, the risk of dialysis dependence was increased in the accelerated RRT group when those patients used non-CRRT modality or had high SOFA scores. All the literatures reviewed in this study were highly heterogeneous and potentially subject to biases. Trial registration CRD42020201466, Sep 07, 2020. https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=201466 .

Peritoneal dialysis with a lower dosage versus conventional intermittent hemodialysis in acute kidney injury: A propensity-matched study

BACKGROUND

Literature regarding the outcomes of lower dosage peritoneal dialysis (PD) in treating acute kidney injury (AKI) among resource-limited setting is sparse. This study aims to compare the risk of mortality in patients with AKI receiving lower PD dosage and conventional intermittent hemodialysis (IHD) in Thailand.

METHODS

In a tertiary center in Thailand, a matched case-control study using propensity scores in patients with AKI was conducted to compare the outcomes between lower PD dosage (18 L per day for first two sessions, weekly Kt/V 2.2) and IHD (three times a week) from February 2015 to January 2016. The primary outcome was a 30-day in-hospital mortality rate. Secondary outcomes included dialysis dependence at 90 days.

RESULTS

Eighty-four patients were included (28 PD and 56 IHD). Patient characteristics were comparable between two treatment groups. Overall, the mean age was 58 years. Most of the patients were critically ill (87% need mechanical ventilator; mean acute physiological and chronic health evaluation (APACHE II) score: 25). The 30-day in-hospital mortality rate was similar between the PD and IHD patients (57% vs. 46%, p = 0.36). The dialysis dependence rate was also comparable at 90 days. The risk of death among AKI patients was higher in those with respiratory failure, higher APACHE II score, and starting dialysis with blood urea nitrogen greater than 70 mg dL^-1.

CONCLUSION

Clinical outcomes, including risk of mortality and 90-day dialysis dependence among patients with AKI, appear to be comparable between lower dosage PD and IHD.

Comparison of Standard Conservative Treatment and Early Initiation of Renal Replacement Therapy in Pregnancy-related Acute Kidney Injury: A Single-center Prospective Study

INTRODUCTION AND OBJECTIVE

Pregnancy-related acute kidney injury (PRAKI) is one of the most important cause of maternal and fetal morbidity and mortality. Some of the reasons behind PRAKI may be due to sepsis, postpartum hemorrhage, preeclampsia, thrombotic microangiopathies (TMA), and acute fatty liver of pregnancy (AFLP). The timing of initiation of renal replacement therapy (RRT) for better patient outcome is still debatable. We conducted this study to establish whether earlier initiation of RRT in PRAKI improves fetomaternal survival compared to a more conservative approach.

MATERIALS AND METHODS

This is a prospective study, where patients were screened at a multispecialty tertiary care hospital in north India for 1 year. The patients were divided into two groups: early RRT and standard AKI treatment. The demographic profile and clinical characteristics of the patients in terms of age, parity access to antenatal care, fetal outcome, urine output, hematological and biochemical profiles, RRT, duration of hospitalization, recovery of renal function, and patients survival were recorded.

RESULTS

This prospective study conducted included 13 patients in the early RRT group and 23 patients in the standard group. Considering the fetal outcome, the number of fetal deaths in early RRT group were 14.29%, whereas for the standard group it was 85.71%. In all, 75% of early RRT group and 25% of standard group had normal term delivery. Probability test applied showed they were statistically significant. One maternal mortality was there in the standard group. The indices of maternal outcome in PRAKI patients were found to be statistically insignificant.

CONCLUSION

The planning of RRT whether early or late does not make a difference in maternal mortality or morbidity. The fetal outcome is significantly better for patients with early RRT than conservative treatment in PRAKI.

HOW TO CITE THIS ARTICLE

Banerjee A, Mehrotra G. Comparison of Standard Conservative Treatment and Early Initiation of Renal Replacement Therapy in Pregnancy-related Acute Kidney Injury: A Single-center Prospective Study. Indian J Crit Care Med 2020;24(8):688-694.

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

Purpose

The results from randomized controlled trials (RCTs) concerning the timing of initiation of renal replacement therapy (RRT) for patients with acute kidney injury (AKI) are still inconsistent.

Materials and methods

We searched for RCTs, as well as relevant references, focusing on the timing of RRT for AKI patients in the Medline, Embase, Cochrane Library, Google Scholar and Chinese databases from their inception to December 2018.

Results

We included 18 RCTs from 1997 to 2018 involving 2856 patients. Pooled analyses of all RCTs showed no significant difference in mortality between early initiation and delayed initiation of RRT (RR 0.98, 95% CI: 0.89 to 1.08, p = .7) (I² = 2%), and similar results were found in critically ill and community-acquired AKI patients, as well as in a subgroup of patients with sepsis and in cardiac surgery recipients. There was also no difference in the incidence of dialysis independence (RR 0.75, 95% CI: 0.47 to 1.2, p = .2) (I² = 0). However, an early RRT strategy was associated with a significantly higher incidence of the need for RRT for AKI patients (RR 1.24, 95% CI: 1.13 to 1.36, p < .01) (I² = 34%).

Conclusions

As no life-threatening complications occurred, there was no evidence to show any benefit of an early RRT strategy for critically ill or community-acquired AKI patients; in contrast, a delayed strategy might avert the need for RRT.

Acute Renal Failure in Critically Ill COVID-19 Patients With a Focus on the Role of Renal Replacement Therapy: A Review of What We Know So Far

Acute renal failure remains a significant concern in all patients with the coronavirus disease 2019 (COVID-19) infection. Management is particularly challenging in critically ill patients requiring intensive care unit (ICU) level of care. Supportive care in the form of accurate volume correction and avoiding nephrotoxic agents are the chief cornerstone of the management of these patients. The pathophysiology of acute renal failure in COVID-19 is multifactorial, with significant contributions from excessive cytokine release. Gaining a better insight into the pathophysiology of renal failure will hopefully help develop more directed treatment options. A considerable number of these patients deteriorate despite adequate supportive care owing to the complexity of the disease and multi-organ involvement. Renal replacement therapy is used for a long time in critically ill septic patients who develop progressive renal failure despite adequate conservative support. Timing and choice of renal replacement therapy in critically ill COVID-19 patients remains an area of future research that may help decrease mortality in this patient population. 

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.

Prescription of CRRT: a pathway to optimize therapy

Severe acute kidney injury (AKI), especially when caused or accompanied by sepsis, is associated with prolonged hospitalization, progression to chronic kidney disease (CKD), financial burden, and high mortality rate. Continuous renal replacement therapy (CRRT) is a predominant form of renal replacement therapy (RRT) in the intensive care unit (ICU) due to its accurate volume control, steady acid-base and electrolyte correction, and achievement of hemodynamic stability. This manuscript reviews the different aspects of CRRT prescription in critically ill patients with severe AKI, sepsis, and multiorgan failure in ICU. These include the choice of CRRT versus Intermittent and extended hemodialysis (HD), life of the filter/dialyzer including assessment of filtration fraction, anticoagulation including regional citrate anticoagulation (RCA), prescribed versus delivered CRRT dose, vascular access management, timing of initiation and termination of CRRT, and prescription in AKI/sepsis including adsorptive methods of removing endotoxins and cytokines.

Comparison between watchful waiting strategy and early initiation of renal replacement therapy in the critically ill acute kidney injury population: an updated systematic review and meta-analysis

BACKGROUND

The optimal timing of renal replacement therapy (RRT) initiation is debatable. Many articles in this field enrolled trials not based on acute kidney injury. The safety of the watchful waiting strategy has not been fully discussed, and late RRT initiation criteria vary across studies. The effect of early RRT initiation in the AKI population with high plasma neutrophil gelatinase-associated lipocalin (NGAL) has not been examined yet.

METHODS

In accordance with PRISMA guidelines, the PubMed, Embase, and Cochrane databases were systemically searched for randomized controlled trials (RCTs). Trials not conducted in the AKI population were excluded. Data of study characteristics, primary outcome (all-cause mortality), and related secondary outcomes [mechanical ventilation (MV) days, length of hospital stay, RRT days, and length of ICU stay] were extracted. The outcomes were compared between early and late RRT groups by estimating the pooled odds ratio (OR) for binary outcomes and the weighted mean difference for continuous outcomes. Prospective trials were also examined and analyzed using the same method.

RESULTS

Nine RCTs with 1938 patients were included. Early RRT did not provide a survival benefit (pooled OR, 0.88; 95% confidence interval [CI] 0.62-1.27). However, the early RRT group had significantly fewer MV days (pooled mean difference, - 3.98 days; 95% CI - 7.81 to - 0.15 days). Subgroup analysis showed that RCTs enrolling the surgical population (P = .001) and the AKI population with high plasma NGAL (P = .031) had favorable outcomes regarding RRT days in the early initiation group. Moreover, 6 of 9 RCTs were selected for examining the safety of the watchful waiting strategy, and no significant differences were found in primary and secondary outcomes between the early and late RRT groups.

CONCLUSIONS

Overall, early RRT initiation did not provide a survival benefit, but a possible benefit of fewer MV days was detected. Early RRT might also provide the benefit of shorter MV or RRT support in the surgical population and in AKI patients with high plasma NGAL. Depending on the conventional indication for RRT initiation, the watchful waiting strategy is safe on the basis of all primary and secondary outcomes.

Continuous renal replacement therapy in elderly with acute kidney injury

The objective of this article is to raise awareness among physicians of the increasing incidence of acute kidney injury in the elderly population and the utility of continuous renal replacement therapy (CRRT) in its management. While CRRT is frequently applied in younger patients, its use in elderly patients is less frequent, for various reasons, including resistance to such an aggressive intervention from the family and the healthcare team. However, predictors of prognosis have been identified and some studies have concluded that advanced age is not associated with poor outcomes. Decisions regarding management are more complex when dealing with the elderly but like very other patient, the approach should be patient- centered.

Renal Replacement Therapy in the ICU

OBJECTIVES

The incidence of acute kidney injury in critically ill patients is increasing steeply. Acute kidney injury in this setting is associated with high morbidity and mortality. There is no doubt that renal replacement therapy for the most severe forms of acute kidney injury can be life saving, but there are a number of uncertainties about the optimal application of renal replacement therapy for patients with acute kidney injury. The objective of this synthetic review is to present current evidence supporting best practices in renal replacement therapy for critically ill patients with acute kidney injury.

DATA SOURCES

We reviewed literature regarding timing of initiation of renal replacement therapy, optimal vascular access for renal replacement therapy in acute kidney injury, modality selection and dose or intensity of renal replacement therapy, and anticoagulation during renal replacement therapy, using the following databases: MEDLINE and PubMed. We also reviewed bibliographic citations of retrieved articles.

STUDY SELECTION

We reviewed only English language articles.

CONCLUSIONS

Current evidence sheds light on many areas of controversy regarding renal replacement therapy in acute kidney injury, providing a foundation for best practices. Nonetheless, important questions remain to be answered by ongoing and future investigation.

Intensity of renal replacement therapy and outcomes in critically ill patients with acute kidney injury: Critical appraisal of the dosing recommendations

The current care of critically ill patients with severe acute kidney injury requiring dialysis (AKI-D) is limited to supportive management in which renal replacement therapy (RRT) plays a central role. Renal replacement techniques are invasive bioincompatible procedures and are therefore associated with complications that may prove harmful to fragile patients. Inexperience with the standards and lacking or misinterpreted recommendations for the delivery of the RRT dose increases the risk of serious complications. Neither the optimal doses of intermittent or continuous RRTs nor the minimal or maximal effective doses are known. The Kidney Disease Improving Global outcomes (KDIGO) AKI guidelines for RRT dosing recommendations are inflexible, based on limited research, and may be at least partially outdated. High-intensity therapy may be associated with clinically relevant alterations in systemic and renal hemodynamics, profound electrolyte imbalances, the loss of nutrients or thermal energy, and underdosing of antimicrobial agents. However, higher doses of continuous renal replacement therapy (CRRT) may confer a survival benefit for certain subgroups of intensive care patients with severe AKI. Lower CRRT doses than the recommended adequate dosage may not lead to negative health outcomes, at least in Asian patients. Future research should evaluate the demand-capacity concept, recognizing that the delivery of the RRT dose is dynamic and should be modified in response to patient-related factors. There is a need for large-scale studies evaluating whether precision RRT dose modifications may improve patient-centered outcomes in subgroups of critically ill patients.

Renal replacement therapy during extracorporeal membrane oxygenation

The use of extracorporeal membrane oxygenator (ECMO) has significantly increased in the past 20 years. There is a high incidence of acute kidney injury (AKI) in the group of patients on ECMO, with need for continuous renal replacement therapy (CRRT) in most of them. This article will review the basics of CRRT, its indications, the technical aspects of incorporating CRRT with ECMO circuit, data on clinical aspects, and outcomes.

Timing of Renal Replacement Therapy for Severe Acute Kidney Injury in Critically Ill Patients

Acute kidney injury (AKI) affects many ICU patients and is responsible for increased morbidity and mortality. Although lifesaving in many situations, renal replacement therapy (RRT) may be associated with complications, and the appropriate timing of its initiation is still the subject of intense debate. An early initiation strategy can prevent some metabolic complications, whereas a delayed one may allow for renal function recovery in some patients without need for this costly and potentially dangerous technique. For years, most of the knowledge on this issue stemmed from observational studies or small randomized controlled trials. Recent randomized controlled trials have indicated that a watchful waiting strategy (in the absence of life-threatening conditions such as severe hyperkalemia or pulmonary edema) during severe AKI allowed many patients to escape RRT and did not seem to adversely affect survival compared with a strategy of immediate RRT. In addition, data suggest that a delayed strategy may reduce the rate of complications (such as catheter infection) and favor renal function recovery. Ongoing studies will have to both confirm these conclusions and clarify to what extent the delay in initiating RRT can be prolonged. Pending those results, the bulk of evidence suggests that, in the absence of potential severe complications of AKI, delaying RRT is a valid and safe strategy that may also allow for considerable cost savings.

Effects of early dialysis on the outcomes of critically ill patients with acute kidney injury: a systematic review and meta-analysis of randomized controlled trials

The appropriate timing for initiating renal replacement therapy (RRT) in critically ill patients with acute kidney injury (AKI) remains unknown. This meta-analysis aims to assess the efficacy of early initiation of RRT in critically ill patients with AKI. The Pubmed, Embase and Cochrane databases were searched up to August 13, 2019. Only randomized controlled trials (RCTs) comparing the effects of early and late RRT on AKI patients were included. The primary outcome was 28-day mortality. Eleven RCTs including 1131 and 1111 AKI patients assigned to early and late RRT strategies, respectively, were enrolled in this meta-analysis. The pooled 28-day mortality was 38.1% (431/1131) and 40.7% (453/1111) in the patients assigned to early and late RRT, respectively, with no significant difference between groups (risk ratio (RR), 0.95; 95% CI, 0.78-1.15, I2 = 63%). No significant difference was found between groups in terms of RRT dependence in survivors on day 28 (RR, 0.90; 95% CI, 0.67-1.25, I2 = 0%), and recovery of renal function (RR, 1.03; 95% CI, 0.89-1.19, I2 = 56%). The early RRT group had higher risks of catheter-related infection (RR, 1.7, 95% CI, 1.01-2.97, I2 = 0%) and hypophosphatemia (RR, 2.5, 95% CI, 1.25-4.99, I2 = 77%) than the late RRT group. In conclusion, an early RRT strategy does not improve survival, RRT dependence, or renal function recovery in critically ill patients with AKI in comparison with a late RRT strategy. However, clinicians should be vigilant because early RRT can carry higher risks of catheter-related infection and hypophosphatemia during dialysis than late RRT.

Early versus late initiation of renal replacement therapy for acute kidney injury in critically ill patients: A systematic review and meta-analysis

Background

Acute kidney injury is associated with high mortality, and is the most frequent complication encountered in patients residing in the intensive care unit. Although renal replacement therapy (RRT) is the standard of care for acute kidney injury, the optimal timing for initiation is still unknown.

Methods

We conducted a systemic review and meta-analysis of randomized controlled trials evaluating early versus late initiation of RRT in critically ill patients with acute kidney injury. We searched MEDLINE, Embase, and CENTRAL databases from inception to October 15, 2018. We screened studies and extracted data from published reported independently. The primary outcome was short-term mortality.

Results

A total of 2242 patients were included from 11 trials. No statistically significant effect was found for early versus late initiation of RRT on short-term mortality (risk ratio [RR] 0.99, 95% CI 0.84–1.17, p = 0.93) or long-term mortality (RR 0.98, 95% CI 0.85–1.13, p = 0.76). There were also no statistically significant effects on ICU length of stay, hospital length of stay, recovery of renal function, and renal replacement therapy dependence. Early initiation of RRT decreased the risk of metabolic acidosis (RR 0.65, 95% CI 0.43–0.99, p = 0.04), but increased the risk of hypotension (RR 1.24, 95% CI 1.08–1.43, p = 0.003).

Conclusions

In critically ill patients with acute kidney injury, early compared with late initiation of RRT is not associated with favorable mortality outcomes, although it appears to reduce the risk of metabolic acidosis.