Extended Daily Dialysis Versus Continuous Renal Replacement Therapy for Acute Kidney Injury: A Meta-analysis

Long-Term Mortality and Health-Related Quality of Life After Continuous Versus Intermittent Renal Replacement Therapy in ICU Survivors: A Secondary Analysis of the Quality of Life After ICU Study

Purpose: We assessed long-term outcomes in intensive care unit (ICU) survivors with acute kidney injury (AKI) submitted to intermittent or continuous renal replacement therapy (RRT) for comparisons between groups. Methods: The multicenter prospective cohort study included 195 adult ICU survivors with an ICU stay >72 h in 10 ICUs that had at least one episode of AKI treated with intermittent RRT (IRRT) or continuous RRT (CRRT) during ICU stay. The main outcomes were mortality and health-related quality of life (HRQoL). Hospital readmissions and physical dependence were also assessed. Results: Regarding RRT, 83 (42.6%) patients received IRRT and 112 (57.4%) received CRRT. Despite the similarity regarding sociodemographic characteristics, pre-ICU state of health and type of admission between groups, the risk of death (23.5% vs 42.7%; P < .001), the prevalence of sepsis (60.7%) and acute respiratory distress syndrome (17%) were higher at ICU admission among CRRT patients. The severity of critical illness was higher among CRRT patients, regarding the need for mechanical ventilation (75.0% vs 50.6%, P = .002) and vasopressors (91.1% vs 63.9%, P < .001). One year after ICU discharge, 67 of 195 ICU survivors died (34.4%) and, after adjustment for confounders, there were no significant differences in mortality when comparing IRRT and CRTT patients (34.9% vs 33.9%; P = .590), on HRQoL in both physical (41.9% vs 42.2%; P = .926) and mental dimensions (57.6% vs 56.6%; P = .340), and on the number of hospital readmissions and physical dependence. Conclusions: Our study suggests that among ICU survivors RRT modality (IRRT vs CRRT) in the ICU does not impact long-term outcomes after ICU discharge.

Comparison of outcomes of different modalities of renal replacement therapy in patients of acute kidney injury: a single centre prospective observational study

BACKGROUND

Acute Kidney Injury (AKI) is one of the most important causes of in-hospital mortality. The global burden of AKI continues to rise without a marked reduction in mortality. As such, the use of renal replacement therapy (RRT) forms an integral part of AKI management, especially in critically ill patients. There has been much debate over the preferred modality of RRT between continuous, intermittent and intermediate modes. While there is abundant data from Europe and North America, data from tropical countries especially the Indian subcontinent is sparse. Our study aims to provide an Indian perspective on the dialytic management of tropical AKI in a tertiary care hospital setup.

METHODS

90 patients of AKI, 30 each undergoing Continuous Renal Replacement Therapy (CRRT), Intermittent Hemodialysis (IHD) and SLED (Sustained Low-Efficiency Dialysis) were included in this prospective cohort study. At the end of 28 days of hospital stay, discharge or death, outcome measures were ascertained which included mortality, duration of hospital stay, recovery of renal function and requirement of RRT after discharge. In addition median of the net change of renal parameters was also computed across the three groups. Lastly, Kaplan Meier analysis was performed to assess the probability of survival with the use of each modality of RRT.

RESULTS

There was no significant difference in the primary outcome of mortality between the three cohorts (p=0.27). However, CRRT was associated with greater renal recovery (p= 0.015) than IHD or SLED. On the other hand, SLED and IHD were associated with a greater net reduction in blood urea (p=0.004) and serum creatinine (p=0.053).

CONCLUSION

CRRT, IHD and SLED are all complementary to each other and are viable options in the treatment of AKI patients.

Mortality and mode of dialysis: meta-analysis and systematic review

BACKGROUND

The global use of kidney replacement therapy (KRT) has increased, mirroring the incidence of acute kidney injury and chronic kidney disease. Despite its growing clinical usage, patient outcomes with KRT modalities remain controversial. In this meta-analysis, we sought to compare the mortality outcomes of patients with any kidney disease requiring peritoneal dialysis (PD), hemodialysis (HD), or continuous renal replacement therapy (CRRT).

METHODS

The investigation was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). PubMed (MEDLINE), Cochrane Library, and Embase databases were screened for randomized trials and observational studies comparing mortality rates with different KRT modalities in patients with acute or chronic kidney failure. A random-effects model was applied to compute the risk ratio (RR) and 95% confidence intervals (95%CI) with CRRT vs. HD, CRRT vs. PD, and HD vs. PD. Heterogeneity was assessed using I2 statistics, and sensitivity using leave-one-out analysis.

RESULTS

Fifteen eligible studies were identified, allowing comparisons of mortality risk with different dialytic modalities. The relative risk was non-significant in CRRT vs. PD [RR = 0.95, (95%CI 0.53, 1.73), p = 0.92 from 4 studies] and HD vs. CRRT [RR = 1.10, (95%CI 0.95, 1.27), p = 0.21 from five studies] comparisons. The findings remained unchanged in the leave-one-out sensitivity analysis. Although PD was associated with lower mortality risk than HD [RR = 0.78, (95%CI 0.62, 0.97), p = 0.03], the significance was lost with the exclusion of 4 out of 5 included studies.

CONCLUSION

The current evidence indicates that while patients receiving CRRT may have similar mortality risks compared to those receiving HD or PD, PD may be associated with lower mortality risk compared to HD. However, high heterogeneity among the included studies limits the generalizability of our findings. High-quality studies comparing mortality outcomes with different dialytic modalities in CKD are necessary for a more robust safety and efficacy evaluation.

Is SLED Efficient in Sepsis Associated Acute Kidney Injury: Hope but Hold!!

How to cite this article: Chhallani AA. Is SLED Efficient in Sepsis Associated Acute Kidney Injury: Hope but Hold!! Indian J Crit Care Med 2024;28(1):5-7.

The Use of Sustained Low-efficiency Dialysis in the Treatment of Sepsis-associated Acute Kidney Injury in a Low-income Country: A Prospective Cohort Study

Background

Limited data are available regarding the management and outcomes of patients with sepsis-associated acute kidney injury (SA-AKI) requiring dialysis in Sudan. Continuous renal replacement therapy (CRRT) is a highly favored treatment modality in such patients. However, it stays unavailable and expensive treatment in most low-income countries. We aimed to evaluate the use of sustained low-efficiency dialysis (SLED) in the treatment of hemodynamically unstable patients with SA-AKI admitted to the intensive care unit (ICU).

Materials and methods

A prospective cohort was conducted in Baraha Medical City, Khartoum, Sudan. Patients above 18 years of age, who were admitted to the ICU between January and September 2020 with SA-AKI, and required SLED or CRRT were enrolled. These were followed up till death or discharge from the ICU. They were observed regarding their dialysis tolerance, rate of renal recovery, ICU mortality, and cost of therapy. Data analysis was done using SPSS.

Results

Fifty-three adults were enrolled. Their mean age was 62 ± 11 years, and 56.6% were males. Thirty-one patients (58.5%) received SLED and 22 (41.5%) underwent CRRT. Patients in the two groups were age and sex matched and showed no significant differences in their comorbid conditions, source of sepsis, sequential organ failure assessment (SOFA) score, and their indications for dialysis (p > 0.05). Patients treated with SLED showed similar dialysis tolerance, rate of renal recovery, length of ICU admission, and risk of death compared to those treated with CRRT (p > 0.05). Moreover, SLED treatments were less expensive than CRRT, and the costs of ICU admission among the SLED group were significantly less (p < 0.001).

Conclusion

Our study shows that SLED is safe and effective. It is readily available and can be routinely performed in the treatment of hemodynamically unstable patients with SA-AKI at a significantly lower cost.

How to cite this article

Taha AKA, Shigidi MMT, Abdulfatah NM, Alsayed RK. The Use of Sustained Low-efficiency Dialysis in the Treatment of Sepsis-associated Acute Kidney Injury in a Low-income Country: A Prospective Cohort Study. Indian J Crit Care Med 2024;28(1):30-35.

Practical considerations for individualizing drug dosing in critically ill adults receiving renal replacement therapy

Critically ill patients with sepsis admitted to the intensive care unit (ICU) often present with or develop renal dysfunction requiring renal replacement therapy (RRT) in addition to antimicrobial therapy. While early and appropriate antimicrobials for sepsis have been associated with an increased probability of survival, adequate dosing is also required in these patients. Adequate dosing of antimicrobials refers to dosing strategies that achieve serum drug levels at the site of infection that are able to provide a microbiological and/or clinical response while avoiding toxicity from excessive antibiotic exposure. Therapeutic drug monitoring (TDM) is the recommended strategy to achieve this goal, however, TDM is not routinely available in all ICUs and for all antimicrobials. In the absence of TDM, clinicians are therefore required to make dosing decisions based on the clinical condition of the patient, the causative organism, the characteristics of RRT, and an understanding of the physicochemical properties of the antimicrobial. Pharmacokinetics (PK) of antimicrobials can be highly variable between critically ill patients and also within the same patient over the course of their ICU stay. The initiation of RRT, which can be in the form of intermittent hemodialysis, continuous, or prolonged intermittent therapy, further complicates the predictability of drug disposition. This variability highlights the need for individualized dosing. This review highlights the practical considerations for the clinician for antimicrobial dosing in critically ill patients receiving RRT.

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.

Regional citrate anticoagulation (RCA) in critically ill patients undergoing renal replacement therapy (RRT): expert opinion from the SIAARTI-SIN joint commission

Renal replacement therapies (RRT) are essential to support critically ill patients with severe acute kidney injury (AKI), providing control of solutes, fluid balance and acid-base status. To maintain the patency of the extracorporeal circuit, minimizing downtime periods and blood losses due to filter clotting, an effective anticoagulation strategy is required.Regional citrate anticoagulation (RCA) has been introduced in clinical practice for continuous RRT (CRRT) in the early 1990s and has had a progressively wider acceptance in parallel to the development of simplified systems and safe protocols. Main guidelines on AKI support the use of RCA as the first line anticoagulation strategy during CRRT in patients without contraindications to citrate and regardless of the patient's bleeding risk.Experts from the SIAARTI-SIN joint commission have prepared this position statement which discusses the use of RCA in different RRT modalities also in combination with other extracorporeal organ support systems. Furthermore, advise is provided on potential limitations to the use of RCA in high-risk patients with particular attention to the need for a rigorous monitoring in complex clinical settings. Finally, the main findings about the prospective of optimization of RRT solutions aimed at preventing electrolyte derangements during RCA are discussed in detail.

ISCCM Guidelines on Acute Kidney Injury and Renal Replacement Therapy

Acute kidney injury (AKI) is a complex syndrome with a high incidence and considerable morbidity in critically ill patients. Renal replacement therapy (RRT) remains the mainstay of treatment for AKI. There are at present multiple disparities in uniform definition, diagnosis, and prevention of AKI and timing of initiation, mode, optimal dose, and discontinuation of RRT that need to be addressed. The Indian Society of Critical Care Medicine (ISCCM) AKI and RRT guidelines aim to address the clinical issues pertaining to AKI and practices to be followed for RRT, which will aid the clinicians in their day-to-day management of ICU patients with AKI.

How to cite this article

Mishra RC, Sodhi K, Prakash KC, Tyagi N, Chanchalani G, Annigeri RA, et al. ISCCM Guidelines on Acute Kidney Injury and Renal Replacement Therapy. Indian J Crit Care Med 2022;26(S2):S13-S42.

Delivering optimal renal replacement therapy to critically ill patients with acute kidney injury

Critical illness is often complicated by acute kidney injury (AKI). In patients with severe AKI, renal replacement therapy (RRT) is deployed to address metabolic dysfunction and volume excess until kidney function recovers. This review is intended to provide a comprehensive update on key aspects of RRT prescription and delivery to critically ill patients. Recently completed trials have enhanced the evidence base regarding several RRT practices, most notably the timing of RRT initiation and anticoagulation for continuous therapies. Better evidence is still needed to clarify several aspects of care including optimal targets for ultrafiltration and effective strategies for RRT weaning and discontinuation.

Machines that help machines to help patients: optimising antimicrobial dosing in patients receiving extracorporeal membrane oxygenation and renal replacement therapy using dosing software

Intensive care unit (ICU) patients with end-organ failure will require specialised machines or extracorporeal therapies to support the failing organs that would otherwise lead to death. ICU patients with severe acute kidney injury may require renal replacement therapy (RRT) to remove fluid and wastes from the body, and patients with severe cardiorespiratory failure will require extracorporeal membrane oxygenation (ECMO) to maintain adequate oxygen delivery whilst the underlying pathology is evaluated and managed. The presence of ECMO and RRT machines can further augment the existing pharmacokinetic (PK) alterations during critical illness. Significant changes in the apparent volume of distribution (V_d) and drug clearance (CL) for many important drugs have been reported during ECMO and RRT. Conventional antimicrobial dosing regimens rarely consider the impact of these changes and consequently, are unlikely to achieve effective antimicrobial exposures in critically ill patients receiving ECMO and/or RRT. Therefore, an in-depth understanding on potential PK changes during ECMO and/or RRT is required to inform antimicrobial dosing strategies in patients receiving ECMO and/or RRT. In this narrative review, we aim to discuss the potential impact of ECMO and RRT on the PK of antimicrobials and antimicrobial dosing requirements whilst receiving these extracorporeal therapies. The potential benefits of therapeutic drug monitoring (TDM) and dosing software to facilitate antimicrobial therapy for critically ill patients receiving ECMO and/or RRT are also reviewed and highlighted.

Sustained low efficiency dialysis is non-inferior to continuous renal replacement therapy in critically ill patients with acute kidney injury: A comparative meta-analysis

BACKGROUND

Critically ill adults with acute kidney injury (AKI) experience considerable morbidity and mortality. This systematic review aimed to compare the effectiveness of continuous renal replacement therapy (CCRT) versus sustained low efficiency dialysis (SLED) for individuals with AKI.

METHODS

We carried out a systematic search of existing databases according to standard methods and random effects models were used to generate the overall estimate. Heterogeneity coefficient was also calculated for each outcome measure.

RESULTS

Eleven studies having 1160 patients with AKI were included in the analyses. Meta-analysis results indicated that there was no statistically significant difference between SLED versus continuous renal replacement therapy (CRRT) in our primary outcomes, like mortality rate (rate ratio [RR] 0.67, 95% confidence interval [CI] 0.44-1.00; P = .05), renal recovery (RR 1.08, 95% CI 0.83-1.42; P = .56), and dialysis dependence (RR = 1.03, 95% CI 0.69-1.53; P = .89). Also, no statistically significant difference was observed for between SLED versus CRRT in the secondary outcomes: that is, length of intensive care unit stay (mean difference -0.16, 95% CI -0.56-0.22; P = .41) and fluid removal rate (mean difference -0.24, 95% CI -0.72-0.24; P = .32). The summary mean difference indicated that there was a significant difference in the serum phosphate clearance among patients treated with SLED and CRRT (mean difference -1.17, 95% CI -1.90 to -0.44, P = .002).

CONCLUSIONS

The analysis indicate that there was no major advantage of using continuous renal replacement compared with sustained low efficiency dialysis in hemodynamically unstable AKI patients. Both modalities are equally safe and effective in treating AKI among critically ill patients.

Acute kidney injury after cardiac surgery: Sustained low efficiency compared to continuous renal replacement therapy

STUDY OBJECTIVE

Sustained low efficiency dialysis (SLED) has been introduced as a mode of renal replacement therapy (RRT) for treating severe cardiac surgery-associated acute kidney injury (CSA-AKI) at some hospitals; SLED is performed using intermittent hemodialysis (IHD) devices but differs from conventional IHD in its duration and intensity. However, there are limited data comparing SLED against more conventional continuous RRT methods. We conducted a retrospective cohort study to compare outcomes of patients with severe CSA-AKI after an institutional transition from continuous RRT to SLED.

DESIGN

Following research ethics approval, we conducted a retrospective cohort study of patients with severe CSA-AKI requiring RRT.

SETTING

Cardiac Intensive Care Unit at the Toronto General Hospital (Toronto, Ontario, Canada) from 1 January 1999 to 31 December 2011.

PATIENTS

351 consecutive patients with severe CSA-AKI requiring RRT after cardiac surgery.

INTERVENTIONS

The RRT mode was continuous RRT before 31 March 2008, and SLED after 1 April 2008.

MEASUREMENTS

The primary outcome was low-cardiac output syndrome (LCOS) and the main secondary outcome was associated costs. Propensity score matched-pairs analyses were used to compare the outcomes of patients in the continuous RRT period versus the SLED period.

MAIN RESULTS

There were 268 patients treated with continuous RRT and 83 patients treated with SLED. The SLED group had a higher weight, higher baseline hemoglobin concentration, and higher prevalence of obstructive lung disease. In propensity score match-pairs analysis (n = 148), the SLED group experienced similar odds of low cardiac output syndrome (odds ratio [OR] 1.06, 95% CI 0.68 to 1.67), death (OR 1.09, 0.94 to 1.28), acute stroke (OR 0.97, 0.83 to 1.13), myocardial infarction (OR 0.92, 0.84 to 1.01). The use of SLED was associated with a reduced cost compared to continuous RRT. The cost differential for 83 treated patients was CAD$130,974 (CAD$178,159.50 vs CAD$309,133.50) in favor of SLED.

CONCLUSIONS

An institutional transition from continuous RRT to SLED, was associated with a significant lower cost with the use of SLED, while maintaining comparable postoperative outcomes in CSA-AKI patients.

GDF-15 Predicts In-Hospital Mortality of Critically Ill Patients with Acute Kidney Injury Requiring Continuous Renal Replacement Therapy: A Multicenter Prospective Study

Growth differentiation factor-15 (GDF-15) is a stress-responsive cytokine. This study evaluated the association between GDF-15 and in-hospital mortality among patients with severe acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT). Among the multicenter prospective CRRT cohort between 2017 and 2019, 66 patients whose blood sample was available were analyzed. Patients were divided into three groups according to the GDF-15 concentrations. The median GDF-15 level was 7865.5 pg/mL (496.9 pg/mL in the healthy control patients). Baseline characteristics were not different among tertile groups except the severity scores and serum lactate level, which were higher in the third tertile. After adjusting for confounding factors, the patients with higher GDF-15 had significantly increased risk of mortality (second tertile: adjusted hazards ratio [aHR], 3.67; 95% confidence interval [CI], 1.05-12.76; p = 0.041; third tertile: aHR, 6.81; 95% CI, 1.98-23.44; p = 0.002). Furthermore, GDF-15 predicted in-hospital mortality (area under the curve, 0.710; 95% CI, 0.585-0.815) better than APACHE II and SOFA scores. Serum GDF-15 concentration was elevated in AKI patients requiring CRRT, higher in more severe patients. GDF-15 is a better independent predictor for in-hospital mortality of critically ill AKI patients than the traditional risk scoring system such as APACHE II and SOFA scores.

Severe methanol poisoning treated with a novel hemodialysis system: a case report, analysis, and review

In May and June 2020, an outbreak of methanol poisoning arose in the southwest United States linked to ingestion of contaminated hand sanitizer imported during the coronavirus disease 2019 pandemic, ultimately resulting in over a dozen hospitalizations and at least four deaths in New Mexico and Arizona. In this report, we describe one of these cases in which profound methanol intoxication was successfully treated with the Tablo® Hemodialysis System, the first reported case of toxic alcohol poisoning treated with this novel device. We carry out a formal regression analysis of the serial methanol levels obtained in this case to conservatively estimate that intermittent hemodialysis with Tablo achieved a clearance of methanol of 239 mL/min (95% confidence interval, 173–305 mL/min), a clearance that is well within the previously published standard of care. We conclude by reviewing both the treatment of toxic alcohol poisoning and the determinants of small molecule clearance with hemodialysis, emphasizing the importance of optimizing the dialytic treatment of intoxications with extended treatment times and the use of high-efficiency dialyzers.

Vancomycin Population Pharmacokinetics in Critically Ill Adults During Sustained Low-Efficiency Dialysis

BACKGROUND

Sustained low-efficiency dialysis (SLED) is a hybrid form of dialysis that is increasingly used in critically ill patients with kidney injury and hemodynamic instability. Antimicrobial dosing for patients receiving SLED is informed by pharmacokinetic studies that describe the drug clearance. Studies available to assist in the dosing of vancomycin in the context of SLED are lacking.

OBJECTIVE

The objective of this prospective observational study was to describe the population pharmacokinetics of vancomycin in critically ill patients receiving SLED, and use simulation studies to propose dosing strategies.

METHODS

Serial serum samples were obtained from 31 critically ill patients prescribed vancomycin while receiving SLED. Vancomycin concentrations were quantified in plasma using a validated liquid chromatography mass spectrometry/mass spectrometry method. A population pharmacokinetic model was developed, and Monte Carlo simulation was used to determine the probability of target attainment at different doses.

RESULTS

From a total of 335 serum samples from 31 patients receiving 52 sessions of SLED therapy, a two-compartment linear model with zero-order input was developed. The mean (standard deviation) clearance of vancomycin on and off SLED was 5.97 (4.04) and 2.40 (1.46) L/h, respectively. Using pharmacodynamic targets for efficacy (area under the concentration-time curve from time zero to 24 h [AUC₂₄]/minimum inhibitory concentration [MIC] ≥ 400) and safety (AUC₂₄ ≥ 700), a loading dose of 2400 mg followed by daily doses of 1600 mg is recommended. Subsequent dosing should be informed by therapeutic drug monitoring of vancomycin levels.

CONCLUSIONS

In critically ill patients receiving SLED, vancomycin clearance is highly variable with a narrow therapeutic window. Empiric dosing is proposed but subsequent dosing should be guided by drug levels.

Short-term prognosis and influencing factors of patients with acute kidney injury treated with prolonged intermittent renal replacement therapy

BACKGROUND

Studies assessing prognosis after prolonged intermittent renal replacement therapy (PIRRT) for acute kidney injury (AKI) are scarce.

AIM

To assess the impact of PIRRT on AKI and factors associated with short-term prognosis.

METHODS

In this retrospective nested case-control study, AKI patients administered PIRRT in Shanghai General Hospital from 01/2012 to 10/2018 were assigned to the 30-day survivor and death groups. Surviving patients were further divided into the kidney recovery and non-recovery groups at 30 and 90 days post-discharge, respectively. Propensity score matching was performed.

RESULTS

Totally 576 patients were included in the non-matched study population, mortality and kidney recovery rates were 51.7% and 33.4%, respectively. After propensity score matching, there were 250 patients in each of the death and survival groups. Low PIRRT frequency (OR = 2.165, 95% CI = 1.178-3.978), infection (OR = 0.447, 95% CI = 0.251-0.795), number of damaged vital organs (OR = 0.478, 95% CI = 0.346-0.661), sodium (OR = 0.958, 95% CI = 0.928-0.988), total protein (OR = 1.047, 95% CI = 1.022-1.072), pre-dialysis thrombin time (TT; OR = 0.959, 95% CI = 0.936-0.983), pre-discharge glomerular filtration rate (GFR; OR = 1.024, 95% CI = 1.017-1.031) and admission ward [reference: renal ward; intensive care unit (OR = 0.042, 95% CI = 0.008-0.211); surgery (OR = 0.092, 95% CI = 0.018-0.465); medical (OR = 0.049, 95% C% CI = 0.009-0.259); other (OR = 0.097, 95% CI = 0.016-0.572)] independently predicted 30-day mortality. Peripherally inserted central catheter (OR = 13.970, 95% CI = 1.439-135.589), urea nitrogen (OR = 0.961, 95% CI = 0.933-0.990) and pre-discharge GFR (OR = 1.102, 95% CI = 1.067-1.137) independently predicted 30-day kidney recovery. Pre-dialysis Scr (OR = 0.997, 95% CI = 0.995-0.999), urea nitrogen (OR = 0.948, 95% CI = 0.912-0.986) and pre-discharge GFR (OR = 1.137 95% CI = 1.088-1.189) independently predicted 90-day kidney recovery.

CONCLUSIONS

PIRRT improves survival and kidney function recovery in AKI patients. In patients with previous GFR ≥ 30 mL/(min-1.73 m² ) and no prior maintenance dialysis, PIRRT at 3-5 sessions/week might be appropriate.

Intermittent Convective Therapies in Patients with Acute Kidney Injury: A Systematic Review with Meta-Analysis

INTRODUCTION

In critically ill patients requiring intermittent renal replacement therapy (RRT), the benefits of convective versus diffusive clearance remain uncertain. We conducted a systematic review and meta-analysis to determine the safety, clinical efficacy, and clearance efficiency of hemofiltration (HF) and hemodiafiltration (HDF) compared to hemodialysis (HD) in patients with acute kidney injury (AKI) receiving intermittent RRT.

METHOD

We searched Medline, Embase, Cochrane Library, and PROSPERO. We included clinical trials and observational studies that reported the use of intermittent HF or HDF in adult patients with AKI. The following outcomes were included: mortality, renal recovery, clearance efficacy, intradialytic hemodynamic stability, circuit loss, and inflammation modulation.

RESULTS

A total of 3,169 studies were retrieved and screened. Four randomized controlled trials and 4 observational studies were included (n: 615 patients). Compared with conventional HD, intermittent convective therapies had no effect on in-hospital mortality (relative risk, 1.23; 95% confidence interval (CI), 0.76-1.99), renal recovery at 30 days (RR, 0.98; 95% CI, 0.82-1.16), time-to-renal recovery (mean difference [MD], 0.77; 95% CI, -6.56 to 8.10), and number of dialysis sessions until renal recovery (MD, -1.34; 95% CI, -3.39 to 0.72). The overall quality of included studies was low, and dialysis parameters were suboptimal for all included studies.

CONCLUSION

This meta-analysis suggests that there is no significant difference in short-term mortality and renal recovery in patients with severe AKI when treated with intermittent HF or HDF compared to conventional HD. This systematic review emphasizes the need for further trials evaluating optimal convective parameters in AKI patients treated with intermittent dialysis.

Renal replacement therapy modality in critically ill patients with acute kidney injury - A network meta-analysis of randomized controlled trials

PURPOSE

This network meta-analysis aims to compare the efficacy and safety of various renal replacement therapy (RRT) modalities in critically ill patients with acute kidney injury (AKI).

MATERIALS AND METHODS

We searched the electronic databases for randomized controlled trials (RCTs) comparing different RRT modalities, including continuous RRT, intermittent RRT, hybrid RRT, and peritoneal dialysis (PD), in critically ill patients with AKI through July 26, 2020. The primary outcomes were renal recovery and short-term mortality. The study protocol was registered with PROSPERO (CRD42020188115).

RESULTS

Twenty-three studies were included. No difference in the renal recovery or short-term mortality was observed among the four RRT modalities (low certainty). The four RRT modalities had similar effects on the incidence of infectious complications (low certainty). PD was associated with less fluid removal volume and lower incidence of hypotension compared with the extracorporeal modalities, yet no difference in the two outcomes was identified among the extracorporeal modalities (very low to moderate certainty).

CONCLUSIONS

No superiority of one particular RRT modality over another in terms of renal recovery and short-term mortality in critically ill patients with AKI. PD exhibited worse fluid removal and better safety in the prevention of hypotension than the extracorporeal modalities.

Determinants of Outcomes of Acute Kidney Injury: Clinical Predictors and Beyond

Acute kidney injury (AKI) is a common clinical syndrome characterized by rapid impairment of kidney function. The incidence of AKI and its severe form AKI requiring dialysis (AKI-D) has been increasing over the years. AKI etiology may be multifactorial and is substantially associated with increased morbidity and mortality. The outcome of AKI-D can vary from partial or complete recovery to transitioning to chronic kidney disease, end stage kidney disease, or even death. Predicting outcomes of patients with AKI is crucial as it may allow clinicians to guide policy regarding adequate management of this problem and offer the best long-term options to their patients in advance. In this manuscript, we will review the current evidence regarding the determinants of AKI outcomes, focusing on AKI-D.

Canadian Association of Paediatric Nephrologists COVID-19 Rapid Response: Guidelines for Management of Acute Kidney Injury in Children

PURPOSE

This article provides guidance on managing acute kidney injury (AKI) and kidney replacement therapy (KRT) in pediatrics during the COVID-19 pandemic in the Canadian context. It is adapted from recently published rapid guidelines on the management of AKI and KRT in adults, from the Canadian Society of Nephrology (CSN). The goal is to provide the best possible care for pediatric patients with kidney disease during the pandemic and ensure the health care team's safety.

INFORMATION SOURCES

The Canadian Association of Paediatric Nephrologists (CAPN) COVID-19 Rapid Response team derived these rapid guidelines from the CSN consensus recommendations for adult patients with AKI. We have also consulted specific documents from other national and international agencies focused on pediatric kidney health. We identified additional information by reviewing the published academic literature relevant to pediatric AKI and KRT, including recent journal articles and preprints related to COVID-19 in children. Finally, our group also sought expert opinions from pediatric nephrologists across Canada.

METHODS

The leadership of the CAPN, which is affiliated with the CSN, solicited a team of clinicians and researchers with expertise in pediatric AKI and acute KRT. The goal was to adapt the guidelines recently adopted for Canadian adult patients for pediatric-specific settings. These included specific COVID-19-related themes relevant to AKI and KRT in a Canadian setting, as determined by a group of kidney disease experts and leaders. An expert group of clinicians in pediatric AKI and acute KRT reviewed the revised pediatric guidelines.

KEY FINDINGS

(1) Current Canadian data do not suggest an imminent threat of an increase in acute KRT needs in children because of COVID-19; however, close coordination between nephrology programs and critical care programs is crucial as the pandemic continues to evolve. (2) Pediatric centers should prepare to reallocate resources to adult centers as needed based on broader health care needs during the COVID-19 pandemic. (3) Specific suggestions pertinent to the optimal management of AKI and KRT in COVID-19 patients are provided. These suggestions include but are not limited to aspects of fluid management, KRT vascular access, and KRT modality choice. (4) Considerations to ensure adequate provision of KRT if resources become scarce during the COVID-19 pandemic.

LIMITATIONS

We did not conduct a formal systematic review or meta-analysis. We did not evaluate our specific suggestions in the clinical environment. The local context, including how the provision of care for AKI and acute KRT is organized, may impede the implementation of many suggestions. As knowledge is advancing rapidly in the area of COVID-19, suggestions may become outdated quickly. Finally, most of the literature for AKI and KRT in COVID-19 comes from adult data, and there are few pediatric-specific studies.

IMPLICATIONS

Given that most acute KRT related to COVID-19 is likely to be required in the pediatric intensive care unit initial setting, close collaboration and planning between critical care and pediatric nephrology programs are needed. Our group will update these suggestions with a supplement if necessary as newer evidence becomes available that may change or add to the recommendations provided.

Prevention and Therapy of AKI in Asia: A Big Challenge

Asia is the largest and most populous continent and has huge differences in socioeconomic status, development, and health care between the different countries and regions within each country. This manifests in the varied causes of acute kidney injury (AKI), particularly higher rates of community-acquired AKI and in the differential access to health care for the population. Because of resource limitations, prevention and treatment of AKI is a difficult challenge. This review highlights the differences in AKI in Asia compared with the developed world and discusses prevention and treatment of AKI within the context of resource limitations.

Short-and long-term outcomes of sustained low efficiency dialysis vs continuous renal replacement therapy in critically ill patients with acute kidney injury

BACKGROUND

Sustained low efficiency dialysis (SLED) has emerged as an alternative to continuous renal replacement therapy (CRRT) for the treatment of acute kidney injury (AKI) in critically ill patients. However, there is limited information on the short- and long-term outcomes of SLED compared to CRRT.

METHODS

We conducted a retrospective cohort study of patients with AKI who commenced either SLED or CRRT in ICUs at a tertiary care hospital in Toronto, Canada. The primary outcome was 90-day all-cause mortality. Secondary outcomes included mortality at one year, and dialysis dependence at 90 days and one year. All outcomes were ascertained by linkage to provincial datasets.

RESULTS

We identified 284 patients, of whom 95 and 189 commenced SLED and CRRT, respectively. Compared to SLED recipients, more CRRT recipients were mechanically ventilated (96% vs 86%, p = 0.002) and receiving vasopressors (94% vs 84%, p = 0.01) at the time of RRT initiation. At 90 days following RRT initiation, 52 (55%) and 126 (67%) SLED and CRRT recipients, respectively, died (adjusted risk ratio (RR) 0.91, 95% CI 0.75-1.11). There was no inter-modality difference in time to death through 90 days (adjusted hazard ratio 0.90, 95% CI 0.64-1.27). Among patients surviving to Day 90, a higher proportion of SLED recipients remained RRT dependent (10 (23%) vs 6 (10%) CRRT recipients, adjusted RR 2.82, 95% CI 1.02-7.81). At one year, there was no difference in mortality or dialysis dependence.

CONCLUSIONS

Among critically ill patients with acute kidney injury, mortality at 90 days and one year was not different among patients initiating SLED as compared to CRRT.

Myoglobin clearance with continuous veno-venous hemodialysis using high cutoff dialyzer versus continuous veno-venous hemodiafiltration using high-flux dialyzer: a prospective randomized controlled trial

Background

Myoglobin clearance in acute kidney injury requiring renal replacement therapy is important because myoglobin has direct renal toxic effects. Clinical data comparing different modalities of renal replacement therapy addressing myoglobin clearance are limited. This study aimed to compare two renal replacement modalities regarding myoglobin clearance.

Methods

In this prospective, randomized, single-blinded, single-center trial, 70 critically ill patients requiring renal replacement therapy were randomized 1:1 into an intervention arm using continuous veno-venous hemodialysis with high cutoff dialyzer and a control arm using continuous veno-venous hemodiafiltration postdilution with high-flux dialyzer. Regional citrate anticoagulation was used in both groups to maintain the extracorporeal circuit. The concentrations of myoglobin, urea, creatinine, β2-microglobulin, interleukin-6 and albumin were measured before and after the dialyzer at 1 h, 6 h, 12 h, 24 h and 48 h after initiating continuous renal replacement therapy.

Results

Thirty-three patients were allocated to the control arm (CVVHDF with high-flux dialyzer) and 35 patients to the intervention arm (CVVHD with high cutoff dialyzer). Myoglobin clearance, as a primary endpoint, was significantly better in the intervention arm than in the control arm throughout the whole study period. The clearance values for urea and creatinine were higher in the control arm. There was no measurable albumin clearance in both arms. The clearance data for β₂-microglobulin and interleukin-6 were non-inferior in the intervention arm compared to those for the control arm. Dialyzer lifespan was 57.0 [38.0, 72.0] hours in the control arm and 70.0 [56.75, 72.0] hours in the intervention arm (p = 0.029).

Conclusions

Myoglobin clearance using continuous veno-venous hemodialysis with high cutoff dialyzer and regional citrate anticoagulation is better than that with continuous veno-venous hemodiafiltration with regional citrate anticoagulation.

Trial registration

German Clinical Trials Registry (DRKS00012407); date of registration 23/05/2017. https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00012407.

Acute Renal Replacement Therapy in Intensive Care Units versus Outside Intensive Care Units: Are They Different?

Introduction

Acute renal replacement therapy (RRT) is indicated when metabolic and fluid demands exceed total kidney capacity, and demand for kidney function is determined by non-renal comorbidities, severity of acute disease and solute and fluid burden; therefore, the criteria for commencing RRT and dialysis in intensive care units (ICUs) may be different to those outside ICUs.

Objective

We investigated whether criteria for commencing acute RRT and dialysis outside ICU were different to those in ICU and whether these differences affected patient mortality in either setting.

Methods

We performed a retrospective observational study evaluating acute kidney injury (AKI), Kidney Disease Improving Global Outcome 3 (KDIGO3) in adult patients undergoing RRT “in and outside” ICU from 2012 to 2018, in a Brazilian teaching hospital.

Results

We evaluated 913 adults with AKI KDIGO3 undergoing RRT; 629 (68.9%) outside ICU and 284 (31.1%) in ICU. Infections were the main cause of hospitalisation (34.4%). Septic and ischaemic AKI were the main aetiologies of AKI (50.8% and 32.9%, respectively), metabolic and fluid demand to capacity imbalance were the main indications for dialysis (69.7%), and intermittent haemodialysis (IHD) was the primary dialysis method (59.2%). The general mortality rate after 30 days was 59%. There were no differences in gender, age and main diagnosis between groups. Both groups were different in acute tubular necrosis index specific scores (ATN-ISS), AKI aetiology, elderly population, indications for dialysis, dialysis methods and mortality rates. In ICU, patients older than 65 years old, with septic AKI were more prevalent (49.1 versus 41.4%, and 55.1 versus 37.5%, respectively), while ischaemic and nephrotoxic AKI were less frequent (24.3 versus 37 and 10.2 versus 16.3%, respectively), and ATN-ISS was higher (0.74 ± 0.31 versus 0.58 ± 0.16). Similarly, metabolic and fluid demand to capacity imbalance as an indication for acute RRT, prolonged intermittent haemodialysis (PIRRT) and continuous renal replacement therapy (CRRT) were more frequent, while peritoneal dialysis (PD) was less frequent (74.6 versus 69.7%, 31.6 versus 22.4%, and 5.3 versus 17.8%, respectively), and mortality was higher (69 versus 54.7%, respectively). Logistic regression revealed that age, septic AKI and being “in” ICU were factors associated with death.

Conclusion

The criteria for commencing RRT and dialysis in ICU were different to those outside ICU; however, they did not impact on patient outcomes.

CSN COVID-19 Rapid Review Program: Management of Acute Kidney Injury

PURPOSE

Severe acute kidney injury (AKI) is a potential complication of COVID-19-associated critical illness. This has implications for the management of COVID-19-associated AKI and the resulting increased need for kidney replacement therapy (KRT) in the intensive care unit (ICU) and elsewhere in the hospital. The Canadian Society of Nephrology COVID-19 Rapid Review Team has sought to collate and synthesize currently available resources to inform ethically justifiable decisions. The goal is the provision of the best possible care for the largest number of patients with kidney disease while considering how best to ensure the safety of the health care team.

INFORMATION SOURCES

Local, provincial, national, and international guidance and planning documents related to the COVID-19 pandemic; guidance documents available from nephrology and critical care-related professional organizations; recent journal articles and preprints related to the COVID-19 pandemic; expert opinion from nephrologists from across Canada.

METHODS

A working group of kidney specialist physicians was established with representation from across Canada. Kidney physician specialists met via teleconference and exchanged e-mails to refine and agree on the proposed suggestions in this document.

KEY FINDINGS

(1) Nephrology programs should work with ICU programs to plan for the possibility that up to 30% or more of critically ill patients with COVID-19 admitted to ICU will require kidney replacement therapy (KRT). (2) Specific suggestions pertinent to the optimal management of AKI and KRT in patients with COVID-19. These suggestions include, but are not limited to, aspects of fluid management, KRT vascular access, and KRT modality choice. (3) We describe considerations related to ensuring adequate provision of KRT, should resources become scarce during the COVID-19 pandemic.

LIMITATIONS

A systematic review or meta-analysis was not conducted. Our suggestions have not been specifically evaluated in the clinical environment. The local context, including how the provision of acute KRT is organized, may impede the implementation of many suggestions. Knowledge is advancing rapidly in the area of COVID-19 and suggestions may become outdated quickly.

IMPLICATIONS

Given that most acute KRT related to COVID-19 is likely to be required initially in the ICU setting, close collaboration and planning between critical care and nephrology programs is required. Suggestions may be updated as newer evidence becomes available.

Acute cardiorenal syndrome in acute heart failure: focus on renal replacement therapy

Almost half of hospitalised patients with acute heart failure develop acute cardiorenal syndrome. Treatment consists of optimisation of fluid status and haemodynamics, targeted therapy for the underlying cardiac disease, optimisation of heart failure treatment and preventive measures such as avoidance of nephrotoxic agents. Renal replacement therapy may be temporarily needed to support kidney function, mostly in case of diuretic resistant fluid overload or severe metabolic derangement. The best timing to initiate renal replacement therapy and the best modality in acute heart failure are still under debate. Several modalities are available such as intermittent and continuous renal replacement therapy as well as hybrid techniques, based on two main principles: haemofiltration and haemodialysis. Although continuous techniques have been associated with less haemodynamic instability and a greater chance of renal recovery, cohort data are conflicting and randomised controlled trials have not shown a difference in recovery or mortality. In the presence of diuretic resistance, isolated ultrafiltration with individualisation of ultrafiltration rates is a valid option for decongestion in acute heart failure patients. Practical tools to optimise the use of renal replacement therapy in acute heart failure-related acute cardiorenal syndrome were discussed.

Extracorporeal Blood Purification and Organ Support in the Critically Ill Patient during COVID-19 Pandemic: Expert Review and Recommendation

Critically ill COVID-19 patients are generally admitted to the ICU for respiratory insufficiency which can evolve into a multiple-organ dysfunction syndrome requiring extracorporeal organ support. Ongoing advances in technology and science and progress in information technology support the development of integrated multi-organ support platforms for personalized treatment according to the changing needs of the patient. Based on pathophysiological derangements observed in COVID-19 patients, a rationale emerges for sequential extracorporeal therapies designed to remove inflammatory mediators and support different organ systems. In the absence of vaccines or direct therapy for COVID-19, extracorporeal therapies could represent an option to prevent organ failure and improve survival. The enormous demand in care for COVID-19 patients requires an immediate response from the scientific community. Thus, a detailed review of the available technology is provided by experts followed by a series of recommendation based on current experience and opinions, while waiting for generation of robust evidence from trials.

Effect of renal replacement therapy modalities on renal recovery and mortality for acute kidney injury: A PRISMA-compliant systematic review and meta-analysis

Previous investigations showed inconsistent results for comparison in renal recovery, in-hospital, and in-intensive care unit (ICU) mortalities between acute kidney injury (AKI) patients treated with continuous renal replacement therapy (CRRT) and some kinds of intermittent renal replacement therapies (IRRTs). We systematically searched for articles published in the databases (PubMed, Web of Science, EMBASE, Medline, and Google Scholar) until June 2019. We made all statistical analysis using STATA 12.0 software. In the present meta-analysis, relative risks with 95% confidence intervals were calculated for binary outcomes (renal recovery status or mortality). The present study indicated no significant differences in renal recovery, in-hospital mortality, and in-ICU mortality between AKI patients given CRRT and those given sustained low-efficiency dialysis (SLED). Additionally, the study showed no significant difference in in-hospital mortality between AKI patients given CRRT and those given intermittent hemodialysis (IHD), whereas elevated in-ICU mortality was detected in AKI patients given CRRT, compared to those given IHD. The three modalities (CRRT, IHD, and SLED) have their own advantages and disadvantages. More rigorous trials design with large cohort should be made to explore the differences in renal recovery, in-hospital, and in-ICU mortalities between different kinds of RRTs.

Renal Replacement Therapy in Severe Burns: A Multicenter Observational Study

Acute kidney injury (AKI) after severe burns is historically associated with a high mortality. Over the past two decades, various modes of renal replacement therapy (RRT) have been used in this population. The purpose of this multicenter study was to evaluate demographic, treatment, and outcomes data among severe burn patients treated with RRT collectively at various burn centers around the United States. After institutional review board approval, a multicenter observational study was conducted. All adult patients aged 18 or older, admitted with severe burns who were placed on RRT for acute indications but not randomized into a concurrently enrolling interventional trial, were included. Across eight participating burn centers, 171 subjects were enrolled during a 4-year period. Complete data were available in 170 subjects with a mean age of 51 ± 17, percent total body surface area burn of 38 ± 26% and injury severity score of 27 ± 21. Eighty percent of subjects were male and 34% were diagnosed with smoke inhalation injury. The preferred mode of therapy was continuous venovenous hemofiltration at a mean delivered dose of 37 ± 19 (ml/kg/hour) and a treatment duration of 13 ± 24 days. Overall, in hospital, mortality was 50%. Among survivors, 21% required RRT on discharge from the hospital while 9% continued to require RRT 6 months after discharge. This is the first multicenter cohort of burn patients who underwent RRT reported to date. Overall mortality is comparable to other critically ill populations who undergo RRT. Most patients who survive to discharge eventually recover renal function.

Development of a new mortality scoring system for acute kidney injury with continuous renal replacement therapy

AIM

On the basis of the worst outcomes of patients undergoing continuous renal replacement therapy (CRRT) in intensive care unit, previously developed mortality prediction model, Acute Physiologic Assessment and Chronic Health Evaluation II (APACHE II) and the Sequential Organ Failure Assessment (SOFA) needs to be modified.

METHODS

A total of 828 patients who underwent CRRT were recruited. Mortality prediction model was developed for the prediction of death within 7 days after starting the CRRT. Based on regression analysis, modified scores were assigned to each variable which were originally used in the APACHE II and SOFA scoring models. Additionally, a new abbreviated Mortality Scoring system for AKI with CRRT (MOSAIC) was developed after stepwise selection analysis.

RESULTS

We used all the variables included in the APACHE II and SOFA scoring models. The prediction powers indicated by C-statistics were 0.686 and 0.683 for 7-day mortality by the APACHE II and SOFA systems, respectively. After modification of these models, the prediction powers increased up to 0.752 for the APACHE II and 0.724 for the SOFA systems. Using multivariate analysis, seven significant variables were selected in the MOSAIC model wherein its C-statistic value was 0.772. These models also showed good performance with 0.720, 0.734 and 0.773 of C-statistics in the modified APACHE II, modified SOFA and MOSAIC scoring models in the external validation cohort (n = 497).

CONCLUSION

The modified APACHE II/SOFA and newly developed MOSAIC models could be more useful tool for predicting mortality for patients receiving CRRT.

Renal replacement therapy in the ICU: intermittent hemodialysis, sustained low-efficiency dialysis or continuous renal replacement therapy?

PURPOSE OF REVIEW

Severe acute kidney injury in the ICU setting often requires renal replacement therapy (RRT). Intermittent hemodialysis (IHD), hybrid forms of RRT such as sustained low-efficiency dialysis (SLED), as well as continuous renal replacement therapy (CRRT) are the three common modalities of extracorporeal RRT used in the adult ICU setting in developed countries. This review summarizes recently published data regarding comparisons of these three RRT modalities on clinical outcomes (e.g., mortality and recovery of renal function) in severe acute kidney injury (AKI) patients.

RECENT FINDINGS

There is still controversy on the superiority of one RRT modality over another in terms of clinical outcomes in patients with AKI in ICU. Although there is increasing acceptance that CRRT should be used in hemodynamic unstable patients, its survival advantages over IHD remains unproven because of inadequate evidence from suitably powered randomized controlled trials (RCTs). Moreover, CRRT does not show superiority to intermittent renal replacement therapy (IRRT) in hemodynamic stable patients. Although patients receiving sustained low-efficiency dialysis appear to have lower mortality than CRRT, its survival benefit is largely derived from observational studies and is confounded by selection bias. Current literature supports no differences in mortality among the three RRT modalities. However, the effect of choice of RRT modality on short-term and long-term renal outcomes need further studies, especially larger RCTs and longer duration of follow-up.

SUMMARY

There is lack of solid evidence showing superiority of any mode of RRT in patients with severe AKI in terms of patient survival. However, based on observational data, IHD treatment of AKI may delay renal recovery. Patients' hemodynamic status, coexisting medical conditions, local expertise, and availability of staff and resources as well as potential effect on long-term renal outcomes should be taken into consideration when selecting modalities of RRT for adult ICU patients.

[Renal replacement therapy in acute kidney injury : From the indications to cessation]

BACKGROUND

The incidence of acute kidney injury (AKI) has increased over the last decades. Renal replacement therapy (RRT) is increasingly being used. The Kidney Disease: Improving Global Outcomes (KDIGO) guidelines define AKI by serum creatinine (SCr) elevation and decrease in urinary output (UO) and suggest prevention strategies and recommendations on the management of RRT. Treatment options are limited and RRT remains the gold standard as supportive treatment but implies a substantial escalation of treatment. With respect to the indications and management of RRT, there are only a few evidence-based recommendations.

OBJECTIVE

This review summarizes the clinical relevance of AKI and presents the most important aspects on the indications and implementation of RRT.

MATERIAL AND METHODS

The available evidence is summarized based on the current literature.

RESULTS

Implementation of the KDIGO bundles to prevent AKI in high-risk patients reduces the incidence of AKI. In the absence of absolute indications, the evidence-based recommendations on when to initiate RRT are limited and controversial. Intermittent hemodialysis (IHD) and continuous renal replacement therapy (CRRT) procedures can be considered as complementary therapeutic strategies. The CRRT is recommended in hemodynamically unstable patients. Regional citrate anticoagulation is the recommended anticoagulation in CRRT. The optimal effluent dose is effectively 20-25 ml/kg body weight and hour. Spontaneous diuresis is a best predictor of successful cessation of RRT.

CONCLUSION

Risk identification and prevention of AKI are essential. In the absence of absolute indications, initiation and accomplishment of RRT should be patient-adapted and carried out in the clinical context. Newly developed biomarkers could be helpful in the future for a better estimation of the prognosis and for a more precise definition of therapeutic strategies of RRT.

Outcomes and practice patterns with hemodiafiltration in Shanghai: a longitudinal cohort study

BACKGROUND

Globally, there is increased clinical interest and uptake of hemodiafiltration (HDF) for increased removal of uremic toxins. To date, there has been no epidemiological analysis of HDF in China. We present HDF practice patterns and associated mortality risk in Shanghai.

METHODS

This is an observational, prospectively collected, retrospective analysis of 9351 Chinese patients initiating hemodialysis in Shanghai from 2007 to 2014. The primary exposure was hemodialysis sub-modality at inception, classified into hemodiafiltration (HDF) and hemodialysis (HD), with adjustment for concommitant hemoperfusion. The primary outcome was patient mortality. We used Cox proportional hazards regression and Fine and Gray's proportional subhazards regression, with multiple imputation of missing co-variates by the chained equation method, adjusting for demographic and clinical variables.

RESULTS

Overall, patients in the cohort were younger, with a more males, and with a lower body mass index when compared to corresponding non-Asian cohorts. Mortality rate was low although it doubled over the period of observation. HDF utilization increased from 7% of patients in 2007 to 42% of patients in 2014. The majority of patients received HDF once a week. The adjusted hazard ratio of death (95% confidence intervals) for HDF versus HD was 0.85 (0.71-1.03), and corresponding sub-hazard ratio 0.86 (0.71-1.03). There was strong effect modification by age. In those aged 40-60 years, the hazard ratio (95% confidence intervals) was 0.65 (0.45-0.94), and sub-hazard ratio also 0.65 (0.45-0.95).

CONCLUSIONS

Our study has certain limitations resulting from the limited number of co-variates available for modelling, missing data for some co-variates, and the lack of verification of data against source documentation. Notwithstanding, there is evidence of clinical benefit from HDF in China, and potential to improve patient outcomes through the greater removal of middle and larger uremic solutes.

The Japanese clinical practice guideline for acute kidney injury 2016

Acute kidney injury (AKI) is a syndrome which has a broad range of etiologic factors depending on different clinical settings. Because AKI has significant impacts on prognosis in any clinical settings, early detection and intervention is necessary to improve the outcomes of AKI patients. This clinical guideline for AKI was developed by a multidisciplinary approach with nephrology, intensive care medicine, blood purification, and pediatrics. Of note, clinical practice for AKI management which was widely performed in Japan was also evaluated with comprehensive literature search.

Continuous Renal Replacement Therapy: Who, When, Why, and How

Continuous renal replacement therapy (CRRT) is commonly used to provide renal support for critically ill patients with acute kidney injury, particularly patients who are hemodynamically unstable. A variety of techniques that differ in their mode of solute clearance may be used, including continuous venovenous hemofiltration with predominantly convective solute clearance, continuous venovenous hemodialysis with predominantly diffusive solute clearance, and continuous venovenous hemodiafiltration, which combines both dialysis and hemofiltration. The present article compares CRRT with other modalities of renal support and reviews indications for initiation of renal replacement therapy, as well as dosing and technical aspects in the management of CRRT.

Renal replacement therapy in critically ill patients: who, when, why, and how

PURPOSE OF REVIEW

The increasing incidence of acute kidney injury has the immediate effect of a growing need for renal replacement therapy (RRT). Shedding light on the questions of who, when, why, and how RRT should be performed is difficult to accomplish because of ambiguous study results, poor quality evidence, and low standardization.

RECENT FINDINGS

Critically ill patients are exposed to multiple factors known to deteriorate kidney function. Especially severe fluid overload is strongly associated with worse outcome and may be considered as a trigger for initiating RRT. In the absence of life-threatening complications, a strategy of early initiation of RRT might be most advantageous keeping in mind the potential adverse effects of RRT. By providing better hemodynamic stability and superior control of fluid balance continuous RRT is the first choice therapeutic tool as compared with intermittent techniques. The femoral and jugular veins are the preferred insertion sites for temporary catheters. Although data are still weak, there is some preliminary evidence that regional citrate anticoagulation is superior to systemic heparinization.

SUMMARY

The best management of RRT is still a subject of controversy. Continuous RRT with regional citrate anticoagulation via a temporary catheter in a jugular vein is the recommended first choice treatment option in critically ill patients with acute kidney injury.

The Japanese Clinical Practice Guideline for acute kidney injury 2016

Acute kidney injury (AKI) is a syndrome which has a broad range of etiologic factors depending on different clinical settings. Because AKI has significant impacts on prognosis in any clinical settings, early detection and intervention are necessary to improve the outcomes of AKI patients. This clinical guideline for AKI was developed by a multidisciplinary approach with nephrology, intensive care medicine, blood purification, and pediatrics. Of note, clinical practice for AKI management which was widely performed in Japan was also evaluated with comprehensive literature search.

Mortality and Recovery of Renal Function in Acute Kidney Injury Patients Treated with Prolonged Intermittent Hemodialysis Sessions Lasting 10 versus 6 Hours: Results of a Randomized Clinical Trial

PURPOSE

This trial aimed to compare mortality and recovery of renal function in acute kidney injury (AKI) patients treated with different durations of prolonged hemodialysis (PHD) sessions (6 h versus 10 h).

METHODOLOGY

We included patients with sepsis-associated AKI, >18 years, who are in use of a norepinephrine (lower than 0.7 ucg/kg/min).

RESULTS

One hundred and ninety-four patients were treated with 531 sessions of PHD (G1=104 and G2=90 patients). The two groups were similar in age and SOFA. There was no significant difference in hypotension, hypokalemia, and anticoagulation during PHD sessions. The two groups showed differences in filter clotting, hypophosphatemia, and treatment discontinuation (12.3 versus 23.1%, p=0.002; 15.5 versus 25.8%, p=0.005; and 7.9 versus 15.6%, p=0.008, respectively). There was no difference in fluid balance (FB) before and after PHD sessions. Death and complete recovery of renal function were similar (81.3 versus 82.2%, p=0.87 and 21 versus 31.2%, p=0.7, respectively). At logistic regression, the positive FB before and after dialysis was identified as risk factor for death, while volume overload after three PHD sessions and predialysis creatinine were negatively associated with recovery of renal function in 28 days.

CONCLUSION

There was no difference in the mortality and recovery of renal function of AKI patients submitted to different durations of PHD and sessions lasting 10 h presented higher filter clotting, hypophosphatemia, and treatment discontinuation. ISRCTN Registry number is ISRCTN33774458.

Prolonged intermittent renal replacement therapy in children

Wide ranges of age and weight in pediatric patients makes renal replacement therapy (RRT) in acute kidney injury (AKI) challenging, particularly in the pediatric intensive care unit (PICU), wherein children are often hemodynamically unstable. Standard hemodialysis (HD) is difficult in this group of children and continuous veno-venous hemofiltration/dialysis (CVVH/D) has been the accepted modality in the developed world. Unfortunately, due to cost constraints, CVVH/D is often not available and peritoneal dialysis (PD) remains the common mode of RRT in resource-poor facilities. Acute PD has its drawbacks, and intermittent HD (IHD) done slowly over a prolonged period has been explored as an alternative. Various modes of slow sustained IHD have been described in the literature with the recently introduced term prolonged intermittent RRT (PIRRT) serving as an umbrella terminology for all of these modes. PIRRT has been widely accepted in adults with studies showing it to be as effective as CVVH/D but with an added advantage of being more cost-effective. Pediatric data, though scanty, has been promising. In this current review, we elaborate on the practical aspects of undertaking PIRRT in children as well as summarize its current status.

Development of a vancomycin dosing approach for critically ill patients receiving hybrid hemodialysis using Monte Carlo simulation

Objectives

Prolonged intermittent renal replacement therapy is an increasingly popular treatment for acute kidney injury in critically ill patients that runs at different flow rates and durations than conventional hemodialysis or continuous renal replacement therapies. Pharmacokinetic studies conducted in patients receiving prolonged intermittent renal replacement therapy are scarce; consequently, clinicians are challenged to dose antibiotics effectively. The purpose of this study was to develop vancomycin dosing recommendations for patients receiving prolonged intermittent renal replacement therapy.

Methods

Monte Carlo simulations were performed in thousands of virtual patients derived from previously published demographic, pharmacokinetic, and dialytic information derived from critically ill patients receiving vancomycin and other forms of renal replacement therapy. We conducted "in silico" vancomycin pharmacokinetic/pharmacodynamics analyses in these patients receiving prolonged intermittent renal replacement therapy to determine what vancomycin dose would achieve vancomycin 24-h area under the curve (AUC_24h) of 400-700 mg·h/L, a target associated with positive clinical outcomes. Nine different vancomycin dosing regimens were tested using four different, commonly used prolonged intermittent renal replacement therapy modalities. A dosing nomogram based on serum concentration data achieved after the third dose was developed to individualize vancomycin therapy.

Results

An initial vancomycin dose of 15 or 20 mg/kg immediately followed by 15 mg/kg after subsequent prolonged intermittent renal replacement therapy treatments achieved AUC_24h of ≥400 mg·h/L for ≥90% of patients regardless of prolonged intermittent renal replacement therapy duration, modality, or time of vancomycin dose relative to prolonged intermittent renal replacement therapy. Many patients experienced AUC_24h of ≥700 mg·h/L, but once the dosing nomogram was applied to serum concentrations obtained after the third vancomycin dose, 67%-88% of patients achieved AUC_24h of 400-700 mg·h/L.

Conclusion

An initial loading dose of 15-20 mg/kg followed by a maintenance regimen of 15 mg/kg after every prolonged intermittent renal replacement therapy session coupled with serum concentration monitoring should be used to individualize vancomycin dosing. These predictions need clinical verification.

A Monte Carlo Simulation Approach for Beta-Lactam Dosing in Critically Ill Patients Receiving Prolonged Intermittent Renal Replacement Therapy

Cefepime, ceftazidime, and piperacillin/tazobactam are commonly used beta-lactam antibiotics in the critical care setting. For critically ill patients receiving prolonged intermittent renal replacement therapy (PIRRT), limited pharmacokinetic data are available to inform clinicians on the dosing of these agents. Monte Carlo simulations (MCS) can be used to guide drug dosing when pharmacokinetic trials are not feasible. For each antibiotic, MCS using previously published pharmacokinetic data derived from critically ill patients was used to evaluate multiple dosing regimens in 4 different prolonged intermittent renal replacement therapy effluent rates and prolonged intermittent renal replacement therapy duration combinations (4 L/h × 10 hours or 5 L/h × 8 hours in hemodialysis and hemofiltration modes). Antibiotic regimens were also modeled depending on whether drugs were administered during or well before prolonged intermittent renal replacement therapy therapy commenced. The probability of target attainment (PTA) was calculated using each antibiotic's pharmacodynamic target during the first 48 hours of therapy. Optimal doses were defined as the smallest daily dose achieving ≥90% probability of target attainment in all prolonged intermittent renal replacement therapy effluent and duration combinations. Cefepime 1 g every 6 hours following a 2 g loading dose, ceftazidime 2 g every 12 hours, and piperacillin/tazobactam 4.5 g every 6 hours attained the desired pharmacodynamic target in ≥90% of modeled prolonged intermittent renal replacement therapy patients. Alternatively, if an every 6-hours cefepime regimen is not desired, the cefepime 2 g pre-prolonged intermittent renal replacement therapy and 3 g post-prolonged intermittent renal replacement therapy regimen also met targets. For ceftazidime, 1 g every 6 hours or 3 g continuous infusion following a 2 g loading dose also met targets. These recommended doses provide simple regimens that are likely to achieve the pharmacodynamics target while yielding the least overall drug exposure, which should result in lower toxicity rates. These findings should be validated in the clinical setting.

Acute kidney injury: Epidemiology, outcomes, complications, and therapeutic strategies

Acute kidney injury (AKI) is one of the most common serious complications for all hospital admissions, with its incidence increasing among hospitalized patients, particularly those in the intensive care unit. Despite significant improvements in critical care and dialysis technology, AKI is associated with an increased risk of short- and long-term mortality, prolonged hospital stays, and dialysis dependence. These risks are particularly relevant for critically ill patients with AKI severe enough to require renal replacement therapy (RRT). No specific pharmacologic treatment has been established to treat AKI. Hence, the mainstay treatment for patients with AKI is RRT even though there are still several problematic issues regarding its use including RRT modality, dose, and timing. Recently, the impact of AKI on an increased risk of progression to chronic kidney disease (CKD) and end-stage renal disease requiring dialysis or transplantation is attracting increased attention.

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

BACKGROUND

In critically sick adults, sustained low efficiency dialysis [SLED] appears to be better tolerated hemodynamically and outcomes seem to be comparable to CRRT. However, there is paucity of data in critically sick children. In children, two recent studies from Taiwan (n = 11) and India (n = 68) showed benefits of SLED in critically sick children.

AIMS AND OBJECTIVES

The objective of the study was to look at the feasibility and tolerability of sustained low efficiency daily dialysis-filtration [SLEDD-f] in critically sick pediatric patients.

MATERIAL AND METHODS

Design: Retrospective study Inclusion criteria: All pediatric patients who had undergone heparin free SLEDD-f from January 2012 to October 2017. Measurements: Data collected included demographic details, vital signs, PRISM III at admission, ventilator parameters (where applicable), number of inotropes, blood gas and electrolytes before, during, and on conclusion of SLED therapy. Technical information was gathered regarding SLEDD-f prescription and complications.

RESULTS

Between 2012-2017, a total of 242 sessions of SLEDD-f were performed on 70 patients, out of which 40 children survived. The median age of patients in years was 12 (range 0.8-17 years), and the median weight was 39 kg (range 8.5-66 kg). The mean PRISM score at admission was 8.77±7.22. SLEDD-f sessions were well tolerated, with marked improvement in fluid status and acidosis. Premature terminations had to be done in 23 (9.5%) of the sessions. There were 21 sessions (8.6%) terminated due to hypotension and 2 sessions (0.8%) terminated due to circuit clotting. Post- SLEDD-f hypocalcemia occurred in 15 sessions (6.2%), post- SLEDD-f hypophosphatemia occurred in 1 session (0.4%), and post- SLEDD-f hypokalemia occurred in 17 sessions (7.0%).

CONCLUSIONS

This study is the largest compiled data on pediatric SLEDD-f use in critically ill patients. Our study confirms the feasibility of heparin free SLEDD-f in a larger pediatric population, and even in children weighing <20 kg on inotropic support.