Pro/con debate: continuous versus intermittent dialysis for acute kidney injury: a never-ending story yet approaching the finish?

Integration of transcriptomics and metabolomics reveals the molecular mechanisms underlying the effect of nafamostat mesylate on rhabdomyolysis-induced acute kidney injury

Objective: To investigate the role and mechanisms of action of nafamostat mesylate (NM) in rhabdomyolysis-induced acute kidney injury (RIAKI). Methods: RIAKI rats were assigned into control group (CN), RIAKI group (RM), and NM intervention group (NM). Inflammatory cytokines and proenkephalin a 119-159 (PENKID) were assessed. Cell apoptosis and glutathione peroxidase-4 (GPX4) were detected using TUNEL assay and immunohistochemical staining. Mitochondrial membrane potential (MMP) was detected by JC-1 dye. The expression of genes and metabolites after NM intervention was profiled using transcriptomic and metabolomic analysis. The differentially expressed genes (DEGs) were validated using qPCR. The KEGG and conjoint analysis of transcriptome and metabolome were used to analyze the enriched pathways and differential metabolites. The transcription factors were identified based on the animal TFDB 3.0 database. Results: Serum creatinine, blood urea nitrogen, and PENKID were remarkably higher in the RM group and lower in the NM group compared to the CN group. Pro-inflammatory cytokines increased in the RM group and notably decreased following NM treatment compared to the CN group. Tubular pathological damages were markedly attenuated and renal cell apoptosis was reduced significantly in the NM group compared to the RM group. The expression of GPX4 was lower in the RM group compared to the CN group, and it increased significantly after NM treatment. A total of 294 DEGs were identified in the RM group compared with the NM group, of which 192 signaling pathways were enriched, and glutathione metabolism, IL-17 signaling, and ferroptosis-related pathways were the top-ranking pathways. The transcriptional levels of Anpep, Gclc, Ggt1, Mgst2, Cxcl13, Rgn, and Akr1c1 were significantly different between the NM and RM group. Gclc was the key gene contributing to NM-mediated renal protection in RIAKI. Five hundred and five DEGs were annotated. Compared with the RM group, most of the upregulated DEGs in the NM group belonged to Glutathione metabolism, whereas most of the downregulated DEGs were related to the transcription factor Cytokine-cytokine receptor interaction. Conclusion: NM protects the kidneys against RIAKI, which is mainly associated with NM mediated regulation of glutathione metabolism, inflammatory response, ferroptosis-related pathways, and the related key DEGs. Targeting these DEGs might emerge as a potential molecular therapy for RIAKI.

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.

Serum Micronutrient Levels in Critically III Patients Receiving Continuous Renal Replacement Therapy: A Prospective, Observational Study

BACKGROUND

Acute kidney injury (AKI) treated with continuous renal replacement therapy (CRRT) may deplete micronutrient levels. Patients are also at risk for micronutrient depletion due to underlying illness(s), poor nutrient intake prior to intensive care unit (ICU) admission and/or increased requirements. We determined vitamin and trace element status before, during and after CRRT in critically ill patients.

METHODS

This prospective observational study performed in mixed medical and surgical ICU patients. Serial serum vitamin B6 and vitamin C concentrations were measured by HPLC and folic acid by ECLIA. Serum chromium, copper, selenium, and zinc were measured using ICP-MS. Serum ceruloplasmin was measured by the Erel method.

RESULTS

Fifty adult ICU patients with AKI were recruited. The median APACHE II score on ICU admission was high at 24.0 (6.0-33.0). The median days on CRRT was 2.0 (2.0-4.0) days. At baseline (within 10-15 minutes of CRRT initiation), serum vitamin C, selenium and zinc were below normal. Serum vitamin B6 levels at 72 hours on CRRT were significantly lower than at 24 hours (p=0.011). Serum vitamin C values fell significantly at 24 and 72 hours during CRRT (p=0.030 and p=0.001), respectively, and remained low 24 and 48 hours after CRRT was stopped (p=0.021). At baseline and during CRRT, 96% of participants had at least two or more micronutrient levels below the normal range.

CONCLUSION

Serum vitamin C, selenium and zinc concentrations were below the normal range at baseline. CRRT was associated with a significant further decrease in levels of vitamin C, selenium and zinc.

CLINICAL RELEVANCY STATEMENT

Critically ill patients who were experienced CRRT had serum vitamin C, selenium and zinc below the normal range during and after CRRT. Also, 96% of participants had at least two or more micronutrient levels below normal at baseline and during CRRT. This article is protected by copyright. All rights reserved.

Dialysis and Extracorporeal Therapies for Enhanced Elimination of Toxic Ingestions and Poisoning

Poisoning and toxic ingestions cause significant morbidity and mortality worldwide. Extracorporeal therapies such as dialysis, haemoperfusion and plasma exchange are selectively applied to patients with severe intoxications unresponsive to standard interventions and can be lifesaving. Extracorporeal therapies are a complex but fundamental aspect of the practice of nephrology. Without high-quality evidence to guide implementation, an understanding of toxicokinetics and the physiochemical principles of the enhanced elimination techniques is especially important. This review provides a comphrensive, user-friendly outline of the application of extracorporeal therapy in the poisoned patient.

Management of acute renal replacement therapy in critically ill cirrhotic patients

Renal replacement therapy (RRT) in cirrhotic patients encompasses a number of issues related to the particular characteristics of this population, especially in the intensive care unit (ICU) setting. The short-term prognosis of cirrhotic patients with acute kidney injury is poor, with a mortality rate higher than 65% in patients with RRT requirement, raising questions about the futility of its initiation. Regarding the management of the RRT itself, there is still no consensus with respect to the modality (continuous versus intermittent) or the anticoagulation required to improve the circuit life, which is shorter than similar at-risk populations, despite the altered haemostasis in traditional coagulation tests frequently found in these patients. Furthermore, volume management is one of the most complex issues in this cohort, where tools used for ambulatory dialysis have not yet been successfully reproducible in the ICU setting. This review attempts to shed light on the management of acute RRT in the critically ill cirrhotic population based on the current evidence and the newly available tools. We will discuss the timing of RRT initiation and cessation, the modality, anticoagulation and fluid management, as well as the outcomes of the RRT in this population, and provide a brief review of the albumin extracorporeal dialysis from the point of view of a nephrologist.

Managing patients of shock and acute kidney injury in tertiary care cardiac ICU: Experience with continuous renal replacement therapy

Background

Clinical experience on details of CRRT initiation and outcomes in cardiac intensive care unit (CICU) patients is not available from developing countries like India. This study shares the 5-year clinical experience of managing CICU patients requiring CRRT in a tertiary care cardiac center of North India.

Materials and methods

Medical records of all CICU patients with acute kidney injury (AKI) managed by CRRT from October 2011 to September 2016 at tertiary referral center in North India were retrospectively reviewed. Multiple logistic regression analysis was used to identify predictors of post-CRRT mortality.

Results

A total of 630 patients received CRRT during the study period. Most commonly AKI developed in patients with acute coronary syndrome (30.2 %) with cardiogenic shock. 55.9 % of the CRRT patients were >60 years of age, and/or on multiple supports in ICU including, mechanical ventilation, high doses of inotropes & vasopressors and other cardiovascular support. Of those on CRRT, 130 (20.6 %) patients had died, 215 (34.1 %) were discharged and 285 (45.2 %) could not complete the desired course. Multivariate regression analysis showed independent association of mortality with high vasoactive-inotropic score, single CRRT cycle and low mean arterial pressure in CRRT patients.

Conclusion

About 34.1 % of patients receiving CRRT were alive at discharge, emphasizing the feasibility and utility of CRRT as a promising modality in this population for improving outcomes.

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.

Caring for Critically Ill Children With Suspected or Proven Coronavirus Disease 2019 Infection: Recommendations by the Scientific Sections' Collaborative of the European Society of Pediatric and Neonatal Intensive Care

OBJECTIVES

In children, coronavirus disease 2019 is usually mild but can develop severe hypoxemic failure or a severe multisystem inflammatory syndrome, the latter considered to be a postinfectious syndrome, with cardiac involvement alone or together with a toxic shock like-presentation. Given the novelty of severe acute respiratory syndrome coronavirus 2, the causative agent of the recent coronavirus disease 2019 pandemic, little is known about the pathophysiology and phenotypic expressions of this new infectious disease nor the optimal treatment approach.

STUDY SELECTION

From inception to July 10, 2020, repeated PubMed and open Web searches have been done by the scientific section collaborative group members of the European Society of Pediatric and Neonatal Intensive Care.

DATA EXTRACTION

There is little in the way of clinical research in children affected by coronavirus disease 2019, apart from descriptive data and epidemiology.

DATA SYNTHESIS

Even though basic treatment and organ support considerations seem not to differ much from other critical illness, such as pediatric septic shock and multiple organ failure, seen in PICUs, some specific issues must be considered when caring for children with severe coronavirus disease 2019 disease.

CONCLUSIONS

In this clinical guidance article, we review the current clinical knowledge of coronavirus disease 2019 disease in critically ill children and discuss some specific treatment concepts based mainly on expert opinion based on limited experience and the lack of any completed controlled trials in children at this time.

Liver Transplantation for Acute Liver Failure in Presence of Acute Kidney Injury

Acute liver failure (ALF) is a catastrophic illness, which is associated with high mortality in absence of liver transplantation. ALF is associated with multisystem involvement including acute kidney injury (AKI). AKI worsens the already poor prognosis of ALF. There is limited literature on impact of AKI on outcomes of liver transplantation (LT). The use of continuous renal replacement therapy (CRRT) may have a role in transplant-free survival or bridging to LT. Although results suggest a somewhat lower survival in patients with ALF and AKI, LT is a life-saving option and should not be deferred in absence of other contraindications. In the current review, we discuss impact of AKI on transplant-free survival, possible role of CRRT, and role of LT in patients with ALF associated with AKI.

Single-best Choice Between Intermittent Versus Continuous Renal Replacement Therapy: A Review

Critically ill patients often develop multiorgan dysfunction syndrome. Acute kidney injury (AKI) is part of it. Renal replacement therapy (RRT) remains the primary choice of treatment in severely ill patients who develop AKI. Recent data have shown increased use of RRT in AKI patients. Therefore, the right choice of RRT plays an important role in the renal recovery of such patients. The question of which mode of RRT to apply has been the topic of study in the last two decades. Whether RRT should be conducted in intermittent mode, as intermittent hemodialysis (IHD), or in continuous mode, as continuous renal replacement therapy (CRRT), is still being investigated. CRRT has a hypothetical advantage when compared to IHD, as it involves a process in which there is gradual removal of fluids, better control of urea, better maintenance of the acid/base balance, and hemodynamic stability. However, IHD is more practical, cost-effective, does not require anticoagulation, decreases the bleeding risk, and removes the solute efficiently and rapidly in acute life-threatening conditions. Other modalities of RRT like sustained low-efficiency daily dialysis (SLEDD) and prolonged intermittent renal replacement therapy (PIRRT) have shown to encompass the benefits of both CRRT in terms of hemodynamic stability and IHD in terms of cost-efficiency. Although SLEDD is progressively being used as an alternative to CRRT and IHD, very few studies have shown to support it. In this article, we try to summarize the advantages and disadvantages of the different techniques used in RRT. With SLEDD gaining more popularity among the different modalities of RRT, we want to assess the possibility of its routine implementation as the single-best choice for RRT.

Pharmacokinetics of Benzylpenicillin (Penicillin G) during Prolonged Intermittent Renal Replacement Therapy

Prolonged intermittent renal replacement therapy (PIRRT) is an increasingly adopted method of renal replacement in critically ill patients. Like continuous renal replacement therapy, PIRRT can alter the pharmacokinetics (PK) of many drugs. In this setting, dosing data for antibiotics like benzylpenicillin are lacking. In order to enable clinicians to prescribe benzylpenicillin safely and effectively, knowledge of the effects of PIRRT on the plasma PK of benzylpenicillin is required. Herein, we describe the PK of benzylpenicillin in 2 critically ill patients on PIRRT for the treatment of penicillin-susceptible Staphylococcus aureus bacteremia complicated by infective endocarditis. Blood samples were taken for each patient taken over dosing periods during PIRRT and off PIRRT. Two-compartment PK models described significant differences in the mean clearance of benzylpenicillin with and without PIRRT (6.61 vs. 3.04 L/h respectively). We would suggest a benzylpenicillin dose of 1,800 mg (3 million units) every 6-h during PIRRT therapy as sufficient to attain PK/pharmacodynamic target.

Pharmacokinetics of Ceftolozane-Tazobactam during Prolonged Intermittent Renal Replacement Therapy

BACKGROUND

Prolonged intermittent renal replacement therapy (PIRRT) eliminates many drugs, and without dosing data, for new antibiotics like ceftolozane/tazobactam, suboptimal concentrations and treatment failure are likely.

OBJECTIVES

Herein, we describe the effect of PIRRT on the plasma pharmacokinetics of ceftolozane/tazobactam ad-ministered in a critically ill 55-year-old patient with a polymicrobial sternal wound osteomyelitis, including a multiresistant Pseudomonas aeruginosa.

METHOD

Blood samples were taken over 4 days where the patient received a 7.5-h PIRRT treatment. One- and 2-compartment models were tested for ceftolozane and tazobactam separately, and the log-likelihood ratio and goodness-of-fit plots were used to select the final model.

RESULTS

Two-compartment models were developed for ceftolozane and tazobactam separately and described significant differences in clearance of ceftolozane and tazobactam with and without PIRRT (8.273 vs. 0.393 and 8.020 vs. 0.767 L/h, respectively).

CONCLUSIONS

A ceftolozane/tazobactam dose of 500 mg/250 mg appears to be sufficient to attain pharmacokinetic/pharmacodynamic targets during PIRRT while the manufacturer's recommended dosing of 100 mg/50 mg every 8 h was sufficient during non-PIRRT periods.

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.

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.

Epidemiology of continuous renal replacement therapy in Korea: Results from the National Health Insurance Service claims database from 2005 to 2016

Background

Continuous renal replacement therapy (CRRT) is an important treatment modality for severe acute kidney injury. As such, the epidemiology of CRRT in Korea needs further investigation.

Methods

We conducted a nationwide, population-based study analyzing the claims data from National Health Insurance Service of Korea. All index intensive care unit admission cases of CRRT in government-designated tertiary referral hospitals in Korea from 2005 to 2016 were included. Patients with a history of renal replacement therapy or who were under 20 years old were not considered. In addition to baseline and treatment characteristics, patient outcomes, including all-cause mortality and renal survival rates, were investigated. We stratified the study patients according to 3-year time periods and major regions of the nation.

Results

We included 37,337 patients who received CRRT in Korea. The overall use of CRRT increased over time, and more than 80% of cases of acute renal replacement therapy were CRRT after 2014. Seoul was the region in which the majority of CRRT (45.0%) was performed. The clinical characteristics of CRRT patients were significantly different among time-intervals and regions. Both all-cause mortality and renal survival rates after CRRT were prominently improved in the recent time periods (P < 0.001).

Conclusion

CRRT is a widely used treatment strategy for severe acute kidney injury in Korea. The prognosis of CRRT patients has improved compared to the past. This epidemiological study of CRRT in Korea revealed notable trends with regard to time period and geographic region.

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

BACKGROUND

Sustained low-efficiency dialysis (SLED), is increasingly being used in intensive care units (ICUs) but studies informing drug dosing for such patients is lacking.

OBJECTIVE

To describe the population pharmacokinetics (PKs) of piperacillin/tazobactam in critically ill adults receiving SLED and to provide dosing recommendations.

METHODS

This prospective population PK study was conducted in adult ICU patients prescribed piperacillin/tazobactam while receiving SLED; 321 blood samples were obtained from 34 participants during and between approximately 50 SLED treatments for quantification of piperacillin and tazobactam concentrations in plasma. A population PK model was developed. Monte Carlo simulation was used to determine the probability of target attainment and pathogen-specific fractional target attainment at different doses.

RESULTS

From a 2-compartment linear model with zero-order input, the mean (SD) clearance of piperacillin on SLED and off SLED were 4.81 (8.48) and 1.42 (1.54) L/h, respectively. Tazobactam concentrations were not sufficient for analysis. For the target of 50% fT>MIC (unbound concentrations of drug are above the minimum inhibitory concentration for >50% of the dosing interval), 3-g of piperacillin infused over 0.5 hours every 8 hours was appropriate for susceptible organisms with MIC ≤16 mg/L. For life-threatening infections where the target of 100% fT>MIC is preferred, a 9-g dose administered as a continuous infusion every 24 hours was appropriate for susceptible organisms with MIC ≤32 mg/L.

CONCLUSIONS AND RELEVANCE

In critically ill patients receiving SLED, piperacillin doses need to be guided by the frequency of SLED treatments and susceptibility of the known or suspected pathogen.

Micronutrient Alterations During Continuous Renal Replacement Therapy in Critically Ill Adults: A Retrospective Study

BACKGROUND

Continuous renal replacement therapy (CRRT) is commonly used to provide renal replacement therapy in the intensive care unit. Limited published data suggest that CRRT may lead to depletion of water-soluble vitamins and trace elements. The goal of this study was to identify the incidence of trace element and vitamin deficiencies in critically ill patients during CRRT.

MATERIALS AND METHODS

This study is based on a retrospective chart review of patients who were referred to Emory University Hospital's nutrition support services and had at least 1 serum micronutrient level measured during CRRT (thiamin, pyridoxine, ascorbic acid, folate, zinc, and copper) between April 1, 2009, and June 1, 2012.

RESULTS

Seventy-five patients were included in the study. Nine of 56 patients (16%) had below-normal whole blood thiamin concentrations, and 38 of 57 patients (67%) had below-normal serum pyridoxine levels. Serum ascorbic acid and folate deficiencies were identified among 87% (13 of 15) and 33% (3 of 9) of the study patients, respectively. Nine of 24 patients had zinc deficiency (38%), and 41 of 68 patients had copper deficiency (60%). Of the 75 total subjects, 60 patients (80%) had below-normal levels of at least 1 of the micronutrients measured.

CONCLUSIONS

The incidence of various micronutrient deficiencies in critically ill patients who required CRRT was higher than previously reported. Prospective studies are needed to determine the impact of CRRT on micronutrient status and the potential clinical and metabolic efficacy of supplementation in the intensive care unit setting.

Renal replacement therapy practices for patients with acute kidney injury in China

Recent data indicate AKI is very common among hospitalized Chinese patients and continuous renal replacement therapy (CRRT) is increasingly offered for treatment. However, only anecdotal information regarding CRRT's use in relation to other modalities and the specific manner in which it is prescribed exists currently. This report summarizes the results of a comprehensive physician survey designed to characterize contemporary dialytic management of AKI patients in China, especially with respect to the utilization of CRRT. The survey queried both nephrologists and critical care physicians across a wide spectrum of hospitals about factors influencing initial RRT modality selection, especially patient clinical characteristics and willingness to receive RRT, treatment location, and institutional capabilities. For patients initially treated with CRRT, data related to indication, timing of treatment initiation, dose, anticoagulation technique, and duration of therapy were also collected. Among AKI patients considered RRT candidates, the survey indicated 15.1% (95% CI, 12.3%-17.9%) did not actually receive dialysis at Chinese hospitals. The finding was largely attributed to prohibitively high therapy costs in the view of patients or their families. The survey confirmed the dichotomy in RRT delivery in China, occurring both in the nephrology department (with nephrologists responsible) and the intensive care unit (with critical care physicians responsible). For all patients who were offered and received RRT, the survey participants reported 63.9% (56.4%-71.3%) were treated initially with CRRT and 24.8% (19.2%-30.3%) with intermittent hemodialysis (HD) (P<0.001). The mean percentage of patients considered hemodynamically unstable at RRT initiation was 36.2% (31.3%-41.1%), although this figure was two-fold higher in patients treated initially with CRRT (43.1%; 35.8%-50.4%) in comparison to those initially treated with HD (22.4%; 16.4%-28.4%)(P<0.001). An overwhelming majority of intensive care patients were treated initially with CRRT (86.6%; 79.8-93.4%) while it was the initial modality in only 44.6% (33.5-55.7%) of patients treated in a nephrology department (P<0.001). Approximately 70% of respondents overall reported prescribing a CRRT dose in the range of 20-30 mL/kg/hr while approximately 20% of prescriptions fell above this range. Daily prescribed therapy duration demonstrated a marked divergence from values reported in the literature and standard clinical practice. Overall, the most common average prescribed value (50% of respondents) fell in the 10-20 hr range, with only 18% in the 20-24 hr range. Moreover, 32% of respondents reported an average prescribed value of less than 10 hrs per day. While the percentages for the 10-20 hrs range were essentially the same for nephrology and ICU programs, a daily duration of less than 10 hrs was much more common in nephrology programs (48.0%; 38.3%-57.9%) versus ICU programs (16%; 10.0%-24.6%)(P<0.001). Our analysis demonstrates both similarities and differences between RRT practices for AKI in China and those in the developed world. While some differences are driven by non-medical factors, future studies should explore these issues further as Chinese RRT practices are harmonized with those in the rest of the world.

Dialysis and acute kidney injury: current evidence

Optimization of renal replacement therapy (RRT) for severe acute kidney injury (AKI) has been intensively studied over the last decade. Several large recently published randomized trials have clarified uncertainties regarding dialysis modality selection as well as dialysis dosage. This information will help inform decision makers regarding resource allocation and establishment of treatment targets. The decision to initiate dialysis remains a clinical one, based on individual patient needs. Despite technological advances in renal replacement therapy, AKI continues to be associated with poor outcomes.

Mortality prediction in patients with dialysis-dependent acute kidney injury after cardiac surgery with cardiopulmonary bypass

BACKGROUND

To build a predictive model for patients with dialysis-dependent acute kidney injury (AKI-D) after cardiac surgery with the cardiopulmonary bypass (CPB), according to disease severity.

METHODS

A single-centre, retrospective cohort study was performed to determine the demographic and clinical parameters (including the specific factor, CPB duration) for risk of poor outcome in patients requiring RRT after cardiac surgery with CPB. A new model was built for mortality prediction in these patients on the basis of the identified risk factors and Sequential Organ Failure Assessment score.

RESULTS

The newly developed model showed good discriminatory ability for predicting death in patients with AKI-D after cardiac surgery with CPB. The area under the receiver-operating characteristic (ROC) curve for the score was 0.892 (95% confidence interval, 0.852-0.925). We also determined the criterion for the choice of RRT modality by applying this model. On applying the new model in intermittent haemodialysis patients, a score of ≤3.2 was found safe for selecting the RRT modality.

CONCLUSIONS

The new scoring system was valid and accurate in predicting death for AKI-D patients after open-heart surgery. This system and value for choice of RRT were determined for guidance only, to facilitate decision-making in difficult situations.

Acute kidney injury: an increasing global concern

Despite an increasing incidence of acute kidney injury in both high-income and low-income countries and growing insight into the causes and mechanisms of disease, few preventive and therapeutic options exist. Even small acute changes in kidney function can result in short-term and long-term complications, including chronic kidney disease, end-stage renal disease, and death. Presence of more than one comorbidity results in high severity of illness scores in all medical settings. Development or progression of chronic kidney disease after one or more episode of acute kidney injury could have striking socioeconomic and public health outcomes for all countries. Concerted international action encompassing many medical disciplines is needed to aid early recognition and management of acute kidney injury.

Extracorporeal renal replacement therapy and blood purification in critical care

OBJECTIVE

To review indications methods of renal replacement therapies (RRT) and practical considerations for the creation of a RRT program.

DATA SOURCES

Current human and veterinary literature review with a focus on advanced renal physiology and clinical experience in RRT and acute/chronic kidney diseases.

DATA SYNTHESIS

Renal replacement therapies encompass intermittent hemodialysis, continuous renal replacement therapy as well as some "hybrid" techniques. Each method of RRT has practical and theoretical advantages but currently there is no evidence that one technique is superior to the other.

CONCLUSIONS

RRT is a valuable therapeutic tool for treatment of acute kidney injury and chronic kidney disease. The implementation of an RRT program needs to take into consideration multiple parameters beyond the choice of an RRT platform.

Management of crush victims in mass disasters: highlights from recently published recommendations

Crush syndrome is the second most common cause of death after earthquakes (the first most common is direct trauma). Many logistic problems with the treatment of patients with crush syndrome are due to chaotic disaster circumstances; consequently, medical and logistic recommendations on the treatment of crush victims are needed. In a joint initiative of the Renal Disaster Relief Task Force of the International Society of Nephrology and European Renal Best Practice, a work group of nephrologists, intensivists, surgeons, and logisticians with disaster experience or experts in guideline preparation collaborated to provide comprehensive information and recommendations on the management of crush casualties considering their occurrence with "epidemic" dimensions after mass disasters. The result is the monograph "Recommendations for the Management of Crush Victims in Mass Disasters", which may help provide effective health care to disaster victims with renal problems. This article discusses medical and logistic principles of the treatment of crush victims, both at the disaster field and on admission to hospitals, and guidance is described. The importance of early fluid administration even before extrication of the victims and avoidance of potassium-containing solutions during the treatment of crush victims is underlined. Also, the logistic problems in treating crush casualties are emphasized. The most important aspects of the recently published recommendations are highlighted.

Dialysability of sugammadex and its complex with rocuronium in intensive care patients with severe renal impairment

BACKGROUND

Renal excretion is the primary route for the elimination of sugammadex. We evaluated the dialysability of sugammadex and the sugammadex-rocuronium complex in patients with severe renal impairment in the intensive care unit (ICU).

METHODS

Six patients in the ICU with acute severe renal impairment received general anaesthesia for transoesophageal echocardiography, to replace their tracheal tubes, or for bronchoscopy. Five of the six patients were in the ICU after cardiac/vascular surgery and one for pneumonia-induced respiratory failure. They all received rocuronium 0.6 mg kg(-1), followed 15 min later by sugammadex 4.0 mg kg(-1). Two patients were studied for two dialysis episodes and four patients for four episodes. Rocuronium and sugammadex concentrations were measured in plasma and dialysate at several time points before, during, and after high-flux dialysis. Dialysis clearance in plasma and dialysate, and reduction ratio (RR) (the extent of the plasma concentration reduction at the end of a dialysis episode when compared with before dialysis) were calculated for each dialysis episode.

RESULTS

Dialysis episodes lasted on average 6 h. Observed RRs indicated mean reductions of 69% and 75% in the plasma concentrations of sugammadex and rocuronium, respectively, during the first dialysis episode. Reductions were around 50% during sequential dialysis episodes. On average, dialysis clearance of sugammadex and rocuronium in blood was 78 and 89 ml min(-1), respectively.

CONCLUSIONS

Haemodialysis using a high-flux dialysis method is effective in removing sugammadex and the sugammadex-rocuronium complex in patients with severe renal impairment.

Acute liver failure in adults: an evidence-based management protocol for clinicians

With the goal of providing guidance on the provision of optimal intensive care to adult patients with acute liver failure (ALF), this paper defines ALF and describes a protocol for appropriately diagnosing this relatively rare clinical entity and ascertaining its etiology, where possible. This paper also identifies the few known therapies that may be effective for specific causes of ALF and provides a comprehensive approach for anticipating, identifying, and managing complications. Finally, one of the more important aspects of care for patients with ALF is the determination of prognosis and, specifically, the need for liver transplantation. Prognostic tools are provided to help guide the clinician in this critical decision process. Management of patients with ALF is complex and challenging, even in centers where staff members have high levels of expertise and substantial experience. This evidence-based protocol may, therefore, assist in the delivery of optimal care to this critically ill patient population and may substantially increase the likelihood of positive outcomes.

Clinical review: use of renal replacement therapies in special groups of ICU patients

Acute kidney injury (AKI) in ICU patients is typically associated with other severe conditions that require special attention when renal replacement therapy (RRT) is performed. RRT includes a wide range of techniques, each with specific characteristics and implications for use in ICU patients. In the present review we discuss a wide range of conditions that can occur in ICU patients who have AKI, and the implications this has for RRT. Patients at increased risk for bleeding should be treated without anticoagulation or with regional citrate anticoagulation. In patients who are haemodynamically unstable, continuous therapies are most often employed. These therapies allow slow removal of volume and guarantee a stable blood pH. In patients with cerebral oedema, continuous therapy is recommended in order to prevent decreased cerebral blood flow, which will lead to cerebral ischemia. Continuous therapy will also prevent sudden change in serum osmolality with aggravation of cerebral oedema. Patients with hyponatraemia, as in liver failure or decompensated heart failure, require extra attention because a rapid increase of serum sodium concentration can lead to irreversible brain damage through osmotic myelinolysis. Finally, in patients with severe lactic acidosis, RRT can be used as a bridging therapy, awaiting correction of the underlying cause. Especially in ICU patients who have severe AKI, treatment with RRT requires balancing the pros and cons of different options and modalities. Exact and specific guidelines for RRT in these patients are not available for most clinical situations. In the present article we provide an update on the existing evidence.

Septic AKI in ICU patients. diagnosis, pathophysiology, and treatment type, dosing, and timing: a comprehensive review of recent and future developments

Evidence is accumulating showing that septic acute kidney injury (AKI) is different from non-septic AKI. Specifically, a large body of research points to apoptotic processes underlying septic AKI. Unravelling the complex and intertwined apoptotic and immuno-inflammatory pathways at the cellular level will undoubtedly create new and exciting perspectives for the future development (e.g., caspase inhibition) or refinement (specific vasopressor use) of therapeutic strategies. Shock complicating sepsis may cause more AKI but also will render treatment of this condition in an hemodynamically unstable patient more difficult. Expert opinion, along with the aggregated results of two recent large randomized trials, favors continuous renal replacement therapy (CRRT) as preferential treatment for septic AKI (hemodynamically unstable). It is suggested that this approach might decrease the need for subsequent chronic dialysis. Large-scale introduction of citrate as an anticoagulant most likely will change CRRT management in intensive care units (ICU), because it not only significantly increases filter lifespan but also better preserves filter porosity. A possible role of citrate in reducing mortality and morbidity, mainly in surgical ICU patients, remains to be proven. Also, citrate administration in the predilution mode appears to be safe and exempt of relevant side effects, yet still requires rigorous monitoring. Current consensus exists about using a CRRT dose of 25 ml/kg/h in non-septic AKI. However, because patients should not be undertreated, this implies that doses as high as 30 to 35 ml/kg/h must be prescribed to account for eventual treatment interruptions. Awaiting results from large, ongoing trials, 35 ml/kg/h should remain the standard dose in septic AKI, particularly when shock is present. To date, exact timing of CRRT is not well defined. A widely accepted composite definition of timing is needed before an appropriate study challenging this major issue can be launched.