Quality Improvement Goals for Acute Kidney Injury

Comprehensive versus standard care in post-severe acute kidney injury survivors, a randomized controlled trial

BACKGROUND

Currently, there is a lack of evidence to guide optimal care for acute kidney injury (AKI) survivors. Therefore, post-discharge care by a multidisciplinary care team (MDCT) may improve these outcomes. This study aimed to demonstrate the outcomes of implementing comprehensive care by a MDCT in severe AKI survivors.

METHODS

This study was a randomized controlled trial conducted between August 2018 to January 2021. Patients who survived severe AKI stage 2-3 were enrolled and randomized to be followed up with either comprehensive or standard care for 12 months. The comprehensive post-AKI care involved an MDCT (nephrologists, nurses, nutritionists, and pharmacists). The primary outcome was the feasibility outcomes; comprising of the rates of loss to follow up, 3-d dietary record, drug reconciliation, and drug alert rates at 12 months. Secondary outcomes included major adverse kidney events, estimated glomerular filtration rate (eGFR), and the amount of albuminuria at 12 months.

RESULTS

Ninety-eight AKI stage 3 survivors were enrolled and randomized into comprehensive care and standard care groups (49 patients in each group). Compared to the standard care group, the comprehensive care group had significantly better feasibility outcomes; 3-d dietary record, drug reconciliation, and drug alerts (p < 0.001). The mean eGFR at 12 months were comparable between the two groups (66.74 vs. 61.12 mL/min/1.73 m2, p = 0.54). The urine albumin: creatinine ratio (UACR) was significantly lower in the comprehensive care group (36.83 vs. 177.70 mg/g, p = 0.036), while the blood pressure control was also better in the comprehensive care group (87.9% vs. 57.5%, p = 0.006). There were no differences in the other renal outcomes between the two groups.

CONCLUSIONS

Comprehensive care by an MDCT is feasible and could be implemented for severe AKI survivors. MDCT involvement also yields better reduction of the UACR and better blood pressure control. Trial registration Clinicaltrial.gov: NCT04012008 (First registered July 9, 2019).

Organizational and financial aspects of a continuous renal replacement therapy program

Critically ill patients who develop severe acute kidney injury in the intensive care unit often require treatment with renal replacement therapies (RRTs). This complication is associated with severe morbidity and mortality and high costs, both during hospitalization and postdischarge. This article discusses the operational requirements to develop and conduct a RRT program, as well as the financial implications of this complex form of patient care. The management of these programs must occur in a context where a clear organizational and educational framework and a multidisciplinary team ensures safety, effectiveness, cost-control, and a clear quality control framework.

Comparison of Static and Dynamic Baseline Creatinine Surrogates for Defining Acute Kidney Injury

BACKGROUND

"Dynamic" baseline serum creatinine (sCr), based on a rolling 48-h window, and a static baseline sCr (previous outpatient sCr) were used to define acute kidney injury (AKI).

METHODS

Retrospective cohort study of adult admissions to the University of Alabama (UAB) Health System hospitals for years 2016-2018. Included admissions had >1- and <180-day length of stay, >2 inpatient sCr measurements, and an averaged estimated glomerular filtration rate >15 mL/min/1.73 m2. The final cohort of 62,380 patients included 100,570 admissions, 3,509 inpatient deaths, and 1,916 admissions with inpatient dialysis. AKI was defined by Kidney Disease Improving Global Outcomes (KDIGO) criteria and a static or dynamic baseline sCr. Discrimination was evaluated with area under receiver operator curves (AUC), logistic regression, and net reclassification improvement (NRI).

RESULTS

Preadmission outpatient "static" sCr values were available for 43,433 admissions. The lowest sCr value during a rolling 48-h window before each inpatient sCr defined a "dynamic" baseline sCr. Using point-wise comparisons, the dynamic baseline sCr performed better than static baseline sCr for inpatient mortality (AUC [0.819 vs. 0.741; p < 0.001] and NRI ≥0.306 [p < 0.001]) and inpatient dialysis (AUC [0.903 vs. 0.864; p < 0.001] and NRI ≥0.317 [p < 0.001]).

CONCLUSIONS

The dynamic baseline sCr is available without reference to preadmission sCr values and avoids confounding associated with missing outpatient sCr values. AKI defined with the dynamic baseline sCr significantly improved discrimination of risk for inpatient mortality and dialysis compared to static baseline sCr.

Nephrologist Interventions to Avoid Kidney Replacement Therapy in Acute Kidney Injury

BACKGROUND

Based on the pathophysiology of acute kidney injury (AKI), it is plausible that certain early interventions by the nephrologist could influence its trajectory. In this study, we investigated the impact of 5 early nephrology interventions on starting kidney replacement therapy (KRT), AKI progression, and death.

METHODS

In a prospective cohort at the Hospital Civil of Guadalajara, we followed up for 10 days AKI patients in whom a nephrology consultation was requested. We analyzed 5 early interventions of the nephrology team (fluid adjustment, nephrotoxic withdrawal, antibiotic dose adjustment, nutritional adjustment, and removal of hyperchloremic solutions) after the propensity score and multivariate analysis for the risk of starting KRT (primary objective), AKI progression to stage 3, and death (secondary objectives).

RESULTS

From 2017 to 2020, we analyzed 288 AKI patients. The mean age was 55.3 years, 60.7% were male, AKI KDIGO stage 3 was present in 50.5% of them, sepsis was the main etiology 50.3%, and 72 (25%) patients started KRT. The overall survival was 84.4%. Fluid adjustment was the only intervention associated with a decreased risk for starting KRT (odds ratio [OR]: 0.58, 95% confidence interval [CI]: 0.48-0.70, and p ≤ 0.001) and AKI progression to stage 3 (OR: 0.59, 95% CI: 0.49-0.71, and p ≤ 0.001). Receiving vasopressors and KRT were associated with mortality. None of the interventions studied was associated with reducing the risk of death.

CONCLUSIONS

In this prospective cohort study of AKI patients, we found for the first time that early nephrologist intervention and fluid prescription adjustment were associated with lower risk of starting KRT and progression to AKI stage 3.

Pediatric Nurse and Pharmacist Knowledge of Acute Kidney Injury

OBJECTIVES

In this study, we assessed the knowledge and experience of pediatric pharmacists and nurses at a US tertiary-care pediatric center regarding the risk factors for, recognition of, and best practices for managing an acute kidney injury (AKI) in children.

METHODS

The authors developed a survey to assess the attitudes and knowledge of nurses and pharmacists regarding AKI in hospitalized children, which was reviewed by a small multidisciplinary group for content and length. The final 16-item survey consisted of demographic, self-assessment and attitude, and knowledge questions. All pediatric pharmacists and nurses at the study site received a voluntary online survey via e-mail. Data were analyzed by using descriptive statistics.

RESULTS

A survey was sent to 620 nurses and 50 pharmacists; 148 (25%) and 22 (44%), respectively, completed it. Most respondents were <35 years old and had ≤10 years of experience in both their professions and pediatrics. A total of 72% of pediatric nurses felt identification of AKI was within their scope of practice, and ∼60% felt confident in their ability to do so. More than 80% of pediatric pharmacists felt confident in their abilities to adjust medication doses in pediatric patients with AKI, but <60% felt confident in their ability to estimate the glomerular filtration rate in these patients. Nurses and pharmacists were able to correctly identify specific AKI criteria 60% to 70% and 70% to 90% of the time, respectively.

CONCLUSIONS

Although pediatric nurses and pharmacists have knowledge of AKI prevention and mitigation, gaps exist, and there is a desire for education in recognition of their key roles in the clinical team.

Acute kidney injury

Acute kidney injury (AKI) is defined by a sudden loss of excretory kidney function. AKI is part of a range of conditions summarized as acute kidney diseases and disorders (AKD), in which slow deterioration of kidney function or persistent kidney dysfunction is associated with an irreversible loss of kidney cells and nephrons, which can lead to chronic kidney disease (CKD). New biomarkers to identify injury before function loss await clinical implementation. AKI and AKD are a global concern. In low-income and middle-income countries, infections and hypovolaemic shock are the predominant causes of AKI. In high-income countries, AKI mostly occurs in elderly patients who are in hospital, and is related to sepsis, drugs or invasive procedures. Infection and trauma-related AKI and AKD are frequent in all regions. The large spectrum of AKI implies diverse pathophysiological mechanisms. AKI management in critical care settings is challenging, including appropriate volume control, nephrotoxic drug management, and the timing and type of kidney support. Fluid and electrolyte management are essential. As AKI can be lethal, kidney replacement therapy is frequently required. AKI has a poor prognosis in critically ill patients. Long-term consequences of AKI and AKD include CKD and cardiovascular morbidity. Thus, prevention and early detection of AKI are essential.

Acute kidney injury in the critically ill: an updated review on pathophysiology and management

Acute kidney injury (AKI) is now recognized as a heterogeneous syndrome that not only affects acute morbidity and mortality, but also a patient’s long-term prognosis. In this narrative review, an update on various aspects of AKI in critically ill patients will be provided. Focus will be on prediction and early detection of AKI (e.g., the role of biomarkers to identify high-risk patients and the use of machine learning to predict AKI), aspects of pathophysiology and progress in the recognition of different phenotypes of AKI, as well as an update on nephrotoxicity and organ cross-talk. In addition, prevention of AKI (focusing on fluid management, kidney perfusion pressure, and the choice of vasopressor) and supportive treatment of AKI is discussed. Finally, post-AKI risk of long-term sequelae including incident or progression of chronic kidney disease, cardiovascular events and mortality, will be addressed.

Nephrologist Follow-Up versus Usual Care after an Acute Kidney Injury Hospitalization (FUSION): A Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

Survivors of AKI are at higher risk of CKD and death, but few patients see a nephrologist after hospital discharge. Our objectives during this 2-year vanguard phase trial were to determine the feasibility of randomizing survivors of AKI to early follow-up with a nephrologist or usual care, and to collect data on care processes and outcomes.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed a randomized controlled trial in patients hospitalized with Kidney Disease Improving Global Outcomes (KDIGO) stage 2-3 AKI at four hospitals in Toronto, Canada. We randomized patients to early nephrologist follow-up (standardized basket of care that emphasized BP control, cardiovascular risk reduction, and medication safety) or usual care from July 2015 to June 2017. Feasibility outcomes included the proportion of eligible patients enrolled, seen by a nephrologist, and followed to 1 year. The primary clinical outcome was a major adverse kidney event at 1 year, defined as death, maintenance dialysis, or incident/progressive CKD.

RESULTS

We screened 3687 participants from July 2015 to June 2017, of whom 269 were eligible. We randomized 71 (26%) patients (34 to nephrology follow-up and 37 to usual care). The primary reason stated for declining enrollment included hospitalization-related fatigue (n=65), reluctance to add more doctors to the health care team (n=59), and long travel times (n=40). Nephrologist visits occurred in 24 of 34 (71%) intervention participants, compared with three of 37 (8%) participants randomized to usual care. The primary clinical outcome occurred in 15 of 34 (44%) patients in the nephrologist follow-up arm, and 16 of 37 (43%) patients in the usual care arm (relative risk, 1.02; 95% confidence interval, 0.60 to 1.73).

CONCLUSIONS

Major adverse kidney events are common in AKI survivors, but we found the in-person model of follow-up posed a variety of barriers that was not acceptable to many patients.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Nephrologist Follow-up versus Usual Care after an Acute Kidney Injury Hospitalization (FUSION), NCT02483039 CJASN 16: 1005-1014, 2021. doi: https://doi.org/10.2215/CJN.17331120.

CRRT in developing world

Continuous renal replacement therapy (CRRT) has become a mainstay therapy in the intensive care unit (ICU) and its utilization continues to increase in developed countries. The wide variations of CRRT practice, however, are evident in developing countries while clinicians in these resource-limited countries encounter various barriers such as a limited number of nephrologists and trained staff, a gap of knowledge, machine unavailability, cultural and socioeconomic aspects, high-cost therapy without reimbursement, and administrative as well as governmental barriers. In this article, we demonstrate the situation of CRRT and discuss the barriers of CRRT in a resource-limited setting. We also discuss the strategies to improve CRRT practice. These recommendations can serve as a fundamental guideline for clinicians to implement CRRT in low-resource settings.

Vascular access, membranes and circuit for CRRT

The advances in the technology for providing continuous renal replacement therapy (CRRT) have led to an increase in its utilization throughout the world. However, circuit life continues to be a major problem. It leads not only to decreased delivery of dialysis but also causes blood loss, waste of disposables, alters dose delivery of medications and nutrition, and increases nurse workload, all of which increases healthcare cost. Premature circuit failure can be caused by numerous factors that can be difficult to dissect out. The first component is the vascular access; without a well-placed, functioning access, delivery of CRRT becomes very difficult. This is usually accomplished by placing a short-term dialysis catheter into either the right internal jugular or femoral vein. The tips should be located at the caval atrial junction or inferior vena cava. In addition to establishing suitable vascular access, a comprehensive understanding of the circuit facilitates the development of a methodical approach in providing efficient CRRT characterized by optimal circuit life. Moreover, it aids in determining the cause of circuit failure in patients experiencing recurrent episodes. This review therefore summarizes the essential points that guide providers in establishing optimal vascular access. We then provide an overview of the main components of the CRRT circuit including the blood and fluid pumps, the hemofilter, and pressure sensors, which will assist in identifying the key mechanisms contributing to premature failure of the CRRT circuit.

Convolutional Neural Network Model for Intensive Care Unit Acute Kidney Injury Prediction

INTRODUCTION

Acute kidney injury (AKI) is common among hospitalized patients and has a significant impact on morbidity and mortality. Although early prediction of AKI has the potential to reduce adverse patient outcomes, it remains a difficult condition to predict and diagnose. The purpose of this study was to evaluate the ability of a machine learning algorithm to predict for AKI as defined by Kidney Disease: Improving Global Outcomes (KDIGO) stage 2 or 3 up to 48 hours in advance of onset using convolutional neural networks (CNNs) and patient electronic health record (EHR) data.

METHODS

A CNN prediction system was developed to use EHR data gathered during patients' stays to predict AKI up to 48 hours before onset. A total of 12,347 patient encounters were retrospectively analyzed from the Medical Information Mart for Intensive Care III (MIMIC-III) database. An XGBoost AKI prediction model and the sequential organ failure assessment (SOFA) scoring system were used as comparators. The outcome was AKI onset. The model was trained on routinely collected patient EHR data. Measurements included area under the receiver operating characteristic (AUROC) curve, positive predictive value (PPV), and a battery of additional performance metrics for advance prediction of AKI onset.

RESULTS

On a hold-out test set, the algorithm attained an AUROC of 0.86 and PPV of 0.24, relative to a cohort AKI prevalence of 7.62%, for long-horizon AKI prediction at a 48-hour window before onset.

CONCLUSION

A CNN machine learning-based AKI prediction model outperforms XGBoost and the SOFA scoring system, revealing superior performance in predicting AKI 48 hours before onset, without reliance on serum creatinine (SCr) measurements.

Acute kidney injury is associated with subtle but quantifiable neurocognitive impairments

BACKGROUND

Acute kidney injury (AKI) is associated with long-term morbidity and mortality. The effects of AKI on neurocognitive functioning remain unknown. Our objective was to quantify neurocognitive impairment after an episode of AKI.

METHODS

Survivors of AKI were compared to age-matched controls, as well as a convenience sample of patients matched for cardiovascular risk factors with normal kidney function (active control group). Patients with AKI completed two assessments, while the active control group completed one assessment. The assessment included a standardized test: The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), and a robotic assessment: Kinarm.

RESULTS

The cohort consisted of 21 patients with AKI, 16 of whom completed both assessments, and 21 active control patients. The majority of patients with AKI had Kidney Disease Improving Global Outcomes stage 3 AKI (86%), 57% received dialysis, and 43% recovered to ≤ 25% of their baseline serum creatinine by their first assessment. Compared to the RBANS, which detected little impairment, the Kinarm categorized patients as impaired in visuomotor (10/21, 48%), attention (10/20, 50%), and executive tasks (11/21, 52%) compared to healthy controls. Additionally, patients with AKI performed significantly worse in attention and visuomotor domains when compared to the active controls. Neurocognitive performance was generally not impacted by the need for dialysis or whether kidney function recovered.

CONCLUSION

Robotic technology identified quantifiable neurocognitive impairment in survivors of AKI. Deficits were noted particularly in attention, visuomotor, and executive domains. Further investigation into the downstream health consequences of these neurocognitive impairments is warranted.

Predictors of kidney function recovery among incident ESRD patients

Background

ESRD is considered an irreversible loss of renal function, yet some patients will recover kidney function sufficiently to come off dialysis. Potentially modifiable predictors of kidney recovery, such as dialysis prescription, have not been fully examined.

Methods

Retrospective cohort study using United States Renal Data System (USRDS) data to identify incident hemodialysis (HD) patients between 2012 and 2016, the first 4 years for which dialysis treatment data is available. The primary outcome was kidney recovery within 1 year of ESRD and HD initiation, defined by a specific recovery code and survival off dialysis for at least 30 days. Patient and treatment characteristics were compared between those that recovered versus those that remained dialysis-dependent. A time-dependent survival model was used to identify independent predictors of kidney recovery.

Results

During the study period, there were 372,387 incident HD patients with available data, among whom 16,930 (4.5%) recovered to dialysis-independence. Compared to non-recovery, a higher proportion of patients with kidney recovery were of white race, and non-Hispanic ethnicity. Both groups had a similar age distribution. Patients with an acute kidney injury diagnosis as primary cause of ESRD were most likely to recover, but the most common ESRD diagnosis among recovering patients was type 2 diabetes (29.8% of recovery cases). Higher eGFR and lower albumin at ESRD initiation were associated with increased likelihood of recovery. When examining HD ultrafiltration rate (UFR), each quintile above the first quintile was associated with a progressively lower likelihood of recovery (HR 0.45, 95% CI 0.43–0.48 for highest versus lowest quintile, p < 0.001).

Conclusions

We identified non-modifiable and potentially modifiable factors associated with kidney recovery which may assist clinicians in counseling and monitoring incident ESRD patients with a greater chance to gain dialysis-independence. Clinical trials are warranted to examine the impact of dialysis prescription on subsequent kidney function recovery.

Real-Time Clinical Decision Support Based on Recurrent Neural Networks for In-Hospital Acute Kidney Injury: External Validation and Model Interpretation

Background

Acute kidney injury (AKI) is commonly encountered in clinical practice and is associated with poor patient outcomes and increased health care costs. Despite it posing significant challenges for clinicians, effective measures for AKI prediction and prevention are lacking. Previously published AKI prediction models mostly have a simple design without external validation. Furthermore, little is known about the process of linking model output and clinical decisions due to the black-box nature of neural network models.

Objective

We aimed to present an externally validated recurrent neural network (RNN)–based continuous prediction model for in-hospital AKI and show applicable model interpretations in relation to clinical decision support.

Methods

Study populations were all patients aged 18 years or older who were hospitalized for more than 48 hours between 2013 and 2017 in 2 tertiary hospitals in Korea (Seoul National University Bundang Hospital and Seoul National University Hospital). All demographic data, laboratory values, vital signs, and clinical conditions of patients were obtained from electronic health records of each hospital. We developed 2-stage hierarchical prediction models (model 1 and model 2) using RNN algorithms. The outcome variable for model 1 was the occurrence of AKI within 7 days from the present. Model 2 predicted the future trajectory of creatinine values up to 72 hours. The performance of each developed model was evaluated using the internal and external validation data sets. For the explainability of our models, different model-agnostic interpretation methods were used, including Shapley Additive Explanations, partial dependence plots, individual conditional expectation, and accumulated local effects plots.

Results

We included 69,081 patients in the training, 7675 in the internal validation, and 72,352 in the external validation cohorts for model development after excluding cases with missing data and those with an estimated glomerular filtration rate less than 15 mL/min/1.73 m2 or end-stage kidney disease. Model 1 predicted any AKI development with an area under the receiver operating characteristic curve (AUC) of 0.88 (internal validation) and 0.84 (external validation), and stage 2 or higher AKI development with an AUC of 0.93 (internal validation) and 0.90 (external validation). Model 2 predicted the future creatinine values within 3 days with mean-squared errors of 0.04-0.09 for patients with higher risks of AKI and 0.03-0.08 for those with lower risks. Based on the developed models, we showed AKI probability according to feature values in total patients and each individual with partial dependence, accumulated local effects, and individual conditional expectation plots. We also estimated the effects of feature modifications such as nephrotoxic drug discontinuation on future creatinine levels.

Conclusions

We developed and externally validated a continuous AKI prediction model using RNN algorithms. Our model could provide real-time assessment of future AKI occurrences and individualized risk factors for AKI in general inpatient cohorts; thus, we suggest approaches to support clinical decisions based on prediction models for in-hospital AKI.

Cardiovascular and Renal Disease in Chronic Critical Illness

With advances in critical care, patients who would have succumbed in previous eras now survive through hospital discharge. Many survivors suffer from chronic organ dysfunction and induced frailty, representing an emerging chronic critical illness (CCI) phenotype. Persistent and worsening cardiovascular and renal disease are primary drivers of the CCI phenotype and have pathophysiologic synergy, potentiating one another and generating a downward spiral of worsening disease and clinical outcomes manifest as cardio-renal syndromes. In addition to pharmacologic therapies (e.g., diuretics, beta adrenergic receptor blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and blood pressure control), special consideration should be given to behavioral modifications that avoid the pitfalls of polypharmacy and suboptimal renal and hepatic dosing, to which CCI patients may be particularly vulnerable. Smoking cessation, dietary modifications (e.g., early high-protein nutrition and late low-sodium diets), and increased physical activity are advised. Select patients benefit from cardiac re-synchronization therapy or renal replacement therapy. Coordinated, patient-centered care bundles may improve compliance with standards of care and patient outcomes. Given the complex, heterogeneous nature of cardiovascular and renal disease in CCI and the dismal long-term outcomes, further research is needed to clarify pathophysiologic mechanisms of cardio-renal syndromes in CCI and develop targeted therapies.

Usefulness of the Biomarker TIMP-2•IGFBP7 for Acute Kidney Injury Assessment in Critically Ill Patients: A Narrative Review

OBJECTIVES

To review the clinical usefulness of the biomarker TIMP-2•IGFBP7 in adult, general medical-surgical intensive care unit (ICU) settings.

DATA SOURCES

PubMed (1946 to mid-February 2021) and EMBASE (1947 to mid-February 2021) with bibliographies of retrieved articles reviewed for additional articles.

STUDY SELECTION AND DATA EXTRACTION

Studies evaluating use of the urinary TIMP-2•IGFBP7 assay in adult patients in ICU settings.

DATA SYNTHESIS

Studies published after investigations leading to TIMP-2•IGFBP7 assay approval confirm the appropriateness of considerations discussed in product labeling, such as use of the test within 12 hours of assessment, use of a dichotomous 0.3 (ng/mL)²/1000 cutoff, and use only in combination with other assessments of acute kidney injury (AKI). However, as a biomarker routinely used for early identification of patients at risk for AKI in mixed ICU populations, the additional resources required for TIMP-2•IGFBP monitoring are difficult to justify because of limited data demonstrating usefulness in preventing or ameliorating AKI and its attendant complications.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Biomarkers are potentially useful not only for assessment and diagnosis of AKI, but also for practitioners involved in the management of nephrotoxic medications and medications needing adjustment for decreased kidney function.

CONCLUSIONS

Although there is evidence to suggest that the urinary TIMP-2•IGFBP7 biomarker is helpful in predicting AKI progression in general medical-surgical ICU patients when used within 12 hours of patient assessment in combination with routine testing, including serum creatinine and urine output, there is little evidence that its use leads to improvements in clinically important patient outcomes.

Severity and Duration of Acute Kidney Injury and Chronic Kidney Disease after Cardiac Surgery

We aimed to evaluate whether the duration and stage of acute kidney injury (AKI) are associated with the occurrence of chronic kidney disease (CKD) in patients undergoing cardiac or thoracic aortic surgery. A total of 2009 cases were reviewed. The patients with postoperative AKI stage 1 and higher stage were divided into transient (serum creatinine elevation ≤48 h) or persistent (>48 h) AKI, respectively. Estimated glomerular filtration rate (eGFR) values during three years after surgery were collected. Occurrence of new-onset CKD stage 3 or higher or all-cause mortality was determined as the primary outcome. Multivariable Cox regression and Kaplan-Meier survival analysis were performed. The Median follow-up of renal function after surgery was 32 months. The cumulative incidences of our primary outcome at one, two, and three years after surgery were 19.8, 23.7, and 26.1%. There was a graded significant association of AKI with new-onset CKD during three years after surgery, except for transient stage 1 AKI (persistent stage 1: HR 3.11, 95% CI 2.62-4.91; transient higher stage: HR 4.07, 95% CI 2.98-6.11; persistent higher stage: HR 13.36, 95% CI 8.22-18.72). There was a significant difference in survival between transient and persistent AKI at the same stage. During three years after cardiac surgery, there was a significant and graded association between AKI stages and the development of new-onset CKD, except for transient stage 1 AKI. This association was stronger when AKI lasted more than 48 h at the same stage. Both duration and severity of AKI provide prognostic value to predict the development of CKD.

Improving the quality of care for patients requiring continuous renal replacement therapy

Continuous renal replacement therapy (CRRT) is the preferred extracorporeal kidney support therapy employed to support critically ill patients with acute or chronic kidney dysfunction in intensive care units. Significant heterogeneity in CRRT practice exists in part due to variable logistics, resources, and scarcity of evidence-based CRRT practices. Importantly, homogenization of practice patterns by developing substantial evidence and effective dissemination among providers is essential for optimizing CRRT practices. The emphasis on quality of CRRT delivery has prompted identification of potential quality indicators, development of multifaceted quality improvement initiatives, effective computer science utilization, and a surge of multidisciplinary quality assurance teams that advocate for "best" CRRT practices. This manuscript provides an overview of quality improvement methodologies and reviews candidate quality indicators of CRRT and the impact of quality improvement on enhancing CRRT delivery practices.

Serum Creatinine Monitoring After Acute Kidney Injury in the PICU

OBJECTIVES

It is unknown whether children with acute kidney injury during PICU admission have kidney function monitored after discharge. Objectives: 1) describe postdischarge serum creatinine monitoring after PICU acute kidney injury and 2) determine factors associated with postdischarge serum creatinine monitoring.

DESIGN

Secondary analysis of longitudinal cohort study data.

SETTING

Two PICUs in Montreal and Edmonton, Canada.

PATIENTS

Children (0-18 yr old) surviving PICU admission greater than or equal to 2 days from 2005 to 2011. Exclusions: postcardiac surgery and prior kidney disease. Exposure: acute kidney injury by Kidney Disease: Improving Global Outcomes serum creatinine definition.

INTERVENTIONS

None.

MEASUREMENTS

Primary outcome: postdischarge serum creatinine measured by 90 days, 1 year, and 5-7 years.

SECONDARY OUTCOMES

Healthcare events and nephrology follow-up.

ANALYSIS

Proportions with outcomes; logistic regression to evaluate factors associated with the primary outcome. Kaplan-Meier analysis of time to serum creatinine measurement and healthcare events.

MAIN RESULTS

Of n = 277, 69 (25%) had acute kidney injury; 29/69 (42%), 34/69 (49%), and 51/69 (74%) had serum creatinine measured by 90 days, 1 year, and 5-7 year postdischarge, respectively. Acute kidney injury survivors were more likely to have serum creatinine measured versus nonacute kidney injury survivors at all time points (p ≤ 0.01). Factors associated with 90-day serum creatinine measurement were inpatient nephrology consultation (unadjusted odds ratio [95% CI], 14.9 [1.7-127.0]), stage 2-3 acute kidney injury (adjusted odds ratio, 3.4 [1.1-10.2]), and oncologic admission diagnosis (adjusted odds ratio, 10.0 [1.1-93.5]). A higher proportion of acute kidney injury versus nonacute kidney injury survivors were readmitted by 90 days (25 [36%] vs 44 [21%]; p = 0.01) and 1 year (33 [38%] vs 70 [34%]; p = 0.04). Of 24 acute kidney injury survivors diagnosed with chronic kidney disease or hypertension at 5-7 year follow-up, 16 (67%) had serum creatinine measurement and three (13%) had nephrology follow-up postdischarge.

CONCLUSIONS

Half of PICU acute kidney injury survivors have serum creatinine measured within 1-year postdischarge and follow-up is suboptimal for children developing long-term kidney sequelae. Knowledge translation strategies should emphasize the importance of serum creatinine monitoring after childhood acute kidney injury.

Assessment of Acute Kidney Injury and Longitudinal Kidney Function After Hospital Discharge Among Patients With and Without COVID-19

Importance

Acute kidney injury (AKI) occurs in up to half of patients hospitalized with coronavirus disease 2019 (COVID-19). The longitudinal effects of COVID-19-associated AKI on kidney function remain unknown.

Objective

To compare the rate of change in estimated glomerular filtration rate (eGFR) after hospital discharge between patients with and without COVID-19 who experienced in-hospital AKI.

Design, Setting, and Participants

A retrospective cohort study was conducted at 5 hospitals in Connecticut and Rhode Island from March 10 to August 31, 2020. Patients who were tested for COVID-19 and developed AKI were screened, and those who survived past discharge, did not require dialysis within 3 days of discharge, and had at least 1 outpatient creatinine level measurement following discharge were included.

Exposures

Diagnosis of COVID-19.

Main Outcomes and Measures

Mixed-effects models were used to assess the association between COVID-19-associated AKI and eGFR slope after discharge. The secondary outcome was the time to AKI recovery for the subgroup of patients whose kidney function had not returned to the baseline level by discharge.

Results

A total of 182 patients with COVID-19-associated AKI and 1430 patients with AKI not associated with COVID-19 were included. The population included 813 women (50.4%); median age was 69.7 years (interquartile range, 58.9-78.9 years). Patients with COVID-19-associated AKI were more likely to be Black (73 [40.1%] vs 225 [15.7%]) or Hispanic (40 [22%] vs 126 [8.8%]) and had fewer comorbidities than those without COVID-19 but similar rates of preexisting chronic kidney disease and hypertension. Patients with COVID-19-associated AKI had a greater decrease in eGFR in the unadjusted model (-11.3; 95% CI, -22.1 to -0.4 mL/min/1.73 m2/y; P = .04) and after adjusting for baseline comorbidities (-12.4; 95% CI, -23.7 to -1.2 mL/min/1.73 m2/y; P = .03). In the fully adjusted model controlling for comorbidities, peak creatinine level, and in-hospital dialysis requirement, the eGFR slope difference persisted (-14.0; 95% CI, -25.1 to -2.9 mL/min/1.73 m2/y; P = .01). In the subgroup of patients who had not achieved AKI recovery by discharge (n = 319), COVID-19-associated AKI was associated with decreased kidney recovery during outpatient follow-up (adjusted hazard ratio, 0.57; 95% CI, 0.35-0.92).

Conclusions and Relevance

In this cohort study of US patients who experienced in-hospital AKI, COVID-19-associated AKI was associated with a greater rate of eGFR decrease after discharge compared with AKI in patients without COVID-19, independent of underlying comorbidities or AKI severity. This eGFR trajectory may reinforce the importance of monitoring kidney function after AKI and studying interventions to limit kidney disease after COVID-19-associated AKI.

Racial Differences in AKI Incidence Following Percutaneous Coronary Intervention

BACKGROUND

Undergoing percutaneous coronary intervention (PCI) is a risk factor for AKI development, but few studies have quantified racial differences in AKI incidence after this procedure.

METHODS

We examined the association of self-reported race (Black, White, or other) and baseline eGFR with AKI incidence among patients who underwent PCI at Duke University Medical Center between January 1, 2003, and December 31, 2013. We defined AKI as a 0.3 mg/dl absolute increase in serum creatinine within 48 hours, or ≥1.5-fold relative elevation within 7 days post-PCI from the reference value ascertained within 30 days before PCI.

RESULTS

Of 9422 patients in the analytic cohort (median age 63 years; 33% female; 75% White, 20% Black, 5% other race), 9% developed AKI overall (14% of Black, 8% of White, 10% of others). After adjustment for demographics, socioeconomic status, comorbidities, predisposing medications, PCI indication, periprocedural AKI prophylaxis, and PCI procedural characteristics, Black race was associated with increased odds for incident AKI compared with White race (odds ratio [OR], 1.79; 95% confidence interval [95% CI], 1.48 to 2.15). Compared with Whites, odds for incident AKI were not significantly higher in other patients (OR, 1.30; 95% CI, 0.93 to 1.83). Low baseline eGFR was associated with graded, higher odds of AKI incidence (P value for trend <0.001); however, there was no interaction between race and baseline eGFR on odds for incident AKI (P value for interaction = 0.75).

CONCLUSIONS

Black patients had greater odds of developing AKI after PCI compared with White patients. Future investigations should identify factors, including multiple domains of social determinants, that predispose Black individuals to disparate AKI risk after PCI.

Long-term consequences of acute kidney injury: a narrative review

The incidence of acute kidney injury (AKI) has increased in the past decades. AKI complicates up to 15% of hospitalizations and can reach up to 50-60% in critically ill patients. Besides the short-term impact of AKI in patient outcomes, several studies report the association between AKI and adverse long-term outcomes, such as recurrent AKI episodes in 25-30% of cases, hospital re-admissions in up to 40% of patients, an increased risk of cardiovascular events, an increased risk of progression of chronic kidney disease (CKD) after AKI and a significantly increased long-term mortality. Despite the long-term impact of AKI, there are neither established guidelines on the follow-up care of AKI patients, nor treatment strategies to reduce the incidence of sequelae after AKI. Only a minority of patients have been referred to nephrology post-discharge care, despite the evidence of improved outcomes associated with nephrology referral by addressing cardiovascular risk and risk of progression to CKD. Indeed, AKI survivors should have specialized nephrology follow-up to assess kidney function after AKI, perform medication reconciliation, educate patients on nephrotoxic avoidance and implement strategies to prevent CKD progression. The authors provide a comprehensive review of the transition from AKI to CKD, analyse the current evidence on the long-term outcomes of AKI and describe predisposing risk factors, highlight the importance of follow-up care in these patients and describe the current therapeutic strategies which are being investigated on their impact in improving patient outcomes.

Nephrotoxin Stewardship

Drugs are the third leading cause of acute kidney injury (AKI) in critically ill patients. Nephrotoxin stewardship ensures a structured and consistent approach to safe medication use and prevention of patient harm. Comprehensive nephrotoxin stewardship requires coordinated patient care management strategies for safe medication use, ensuring kidney health, and avoiding unnecessary costs to improve the use of nephrotoxins, renally eliminated drugs, and kidney disease treatments. Implementing nephrotoxin stewardship reduces medication errors and adverse drug events, prevents or reduces severity of drug-associated AKI, prevents progression to or worsening of chronic kidney disease, and alleviates financial burden on the health care system.

Improving the quality of neonatal acute kidney injury care: neonatal-specific response to the 22nd Acute Disease Quality Initiative (ADQI) conference

With the adoption of standardized neonatal acute kidney injury (AKI) definitions over the past decade and the concomitant surge in research studies, the epidemiology of and risk factors for neonatal AKI have become much better understood. Thus, there is now a need to focus on strategies designed to improve AKI care processes with the goal of reducing the morbidity and mortality associated with neonatal AKI. The 22nd Acute Dialysis/Disease Quality Improvement (ADQI) report provides a framework for such quality improvement in adults at risk for AKI and its sequelae. While many of the concepts can be translated to neonates, there are a number of specific nuances which differ in neonatal AKI care. A group of experts in pediatric nephrology and neonatology came together to provide neonatal-specific responses to each of the 22nd ADQI consensus statements.

Individualized acute kidney injury after care

PURPOSE OF REVIEW

The aim of this study was to summarize the current evidence around the impact of individualizing patient care following an episode of acute kidney injury (AKI) in the ICU.

RECENT FINDINGS

Over the last years, evidence has demonstrated that the follow-up care after episodes of AKI is lacking and standardization of this process is likely needed. Although this is informed largely by large retrospective cohort studies, a few prospective observational trials have been performed. Medication reconciliation and patient/caregiver education are important tenants of follow-up care, regardless of the severity of AKI. There is evidence the initiation and/or reinstitution of renin-angiotensin-aldosterone agents may improve patient's outcomes following AKI, although they may increase the risk for adverse events, especially when reinitiated early. In addition, 3 months after an episode of AKI, serum creatinine and proteinuria evaluation may help identify patients who are likely to develop progressive chronic kidney disease over the ensuing 5 years. Lastly, there are emerging differences between those who do and do not require renal replacement therapy (RRT) for their AKI, which may require more frequent and intense follow-up in those needing RRT.

SUMMARY

Although large scale evidence-based guidelines are lacking, standardization of post-ICU-AKI is needed.

Precision renal replacement therapy

PURPOSE OF REVIEW

This article reviews the current evidence supporting the use of precision medicine in the delivery of acute renal replacement therapy (RRT) to critically ill patients, focusing on timing, solute control, anticoagulation and technologic innovation.

RECENT FINDINGS

Precision medicine is most applicable to the timing of RRT in critically ill patients. As recent randomized controlled trials have failed to provide consensus on when to initiate acute RRT, the decision to start acute RRT should be based on individual patient clinical characteristics (e.g. severity of the disease, evolution of clinical parameters) and logistic considerations (e.g. organizational issues, availability of machines and disposables). The delivery of a dynamic dialytic dose is another application of precision medicine, as patients may require different and varying dialysis doses depending on individual patient factors and clinical course. Although regional citrate anticoagulation (RCA) is recommended as first-line anticoagulation for continuous RRT, modifications to RCA protocols and consideration of other anticoagulants should be individualized to the patient's clinical condition. Finally, the evolution of RRT technology has improved precision in dialysis delivery through increased machine accuracy, connectivity to the electronic medical record and automated reduction of downtime.

SUMMARY

RRT has become a complex treatment for critically ill patients, which allows for the prescription to be precisely tailored to the different clinical requirements.

Kidney Recovery From Acute Kidney Injury After Hematopoietic Stem Cell Transplant: A Systematic Review and Meta-Analysis

Patients with the recovery of kidney function after an episode of acute kidney injury (AKI) have better outcomes compared to those without recovery. The current systematic review is conducted to assess the rates of kidney function recovery among patients with AKI or severe AKI requiring kidney replacement therapy (KRT) within 100 days after hematopoietic stem cell transplant (HSCT). Methods The Ovid MEDLINE, EMBASE, and Cochrane databases were systemically searched from database inceptions through August 2019 to identify studies reporting the rates of recovery from AKI after HSCT. The random-effects and generic inverse variance methods of DerSimonian-Laird were used to combine the effect estimates obtained from individual studies. Results A total of 458 patients from eight cohort studies with AKI after HSCT were identified. Overall, the pooled estimated rates of AKI recovery among patients with AKI and severe AKI requiring KRT within 100 days were 58% (95%CI: 37%-78%) and 10% (95%CI: 2%-4%), respectively. Among patients with AKI recovery, the pooled estimated rates of complete and partial AKI recovery were 60% (95%CI: 39%-78%) and 29% (95%CI: 10%-61%), respectively. There was no clear correlation between study year and the rate of AKI recovery (p=0.26). Conclusion The rate of recovery from AKI after HSCT depends on the severity of AKI. While recovery is common, complete recovery is reported in about two-thirds of all AKI patients. The rate of recovery among those with AKI requiring renal replacement therapy (RRT) is substantially lower.

Care of the Survivor of Critical Illness and Acute Kidney Injury: A Multidisciplinary Approach

Acute kidney injury (AKI) is a common complication of critical illness and is associated with adverse short- and long-term health consequences. Survivors of critical illness and AKI experience poor kidney, cardiovascular and quality of life outcomes, along with increased mortality. Yet, many patients surviving AKI are unaware that there is a problem with their kidney health, and post-AKI nephrology follow-up occurs at very low rates. Although there is a paucity of evidence-based studies to guide post-AKI care, attention to risk factors such as hypertension and albuminuria are requisite. There are several ongoing or planned studies which are expected to help inform specific management in the future. Until then, a multidisciplinary approach is warranted to address areas such as quality of life, physical rehabilitation, dietary modifications, and medication reconciliation.

For Whom the Bell Tolls: Acute Kidney Injury and Electronic Alerts for the Pediatric Nephrologist

With the advent of the electronic medical record, automated alerts have allowed for improved recognition of patients with acute kidney injury (AKI). Pediatric patients have the opportunity to benefit from such alerts, as those with a diagnosis of AKI are at risk of developing long-term consequences including reduced renal function and hypertension. Despite extensive studies on the implementation of electronic alerts, their overall impact on clinical outcomes have been unclear. Understanding the results of these studies have helped define best practices in developing electronic alerts with the aim of improving their impact on patient care. As electronic alerts for AKI are applied to pediatric patients, identifying their strengths and limitations will allow for continued improvement in its use and efficacy.

Biomarker-Guided Risk Assessment for Acute Kidney Injury: Time for Clinical Implementation?

Acute kidney injury (AKI) is a common and serious complication in hospitalized patients, which continues to pose a clinical challenge for treating physicians. The most recent Kidney Disease Improving Global Outcomes practice guidelines for AKI have restated the importance of earliest possible detection of AKI and adjusting treatment accordingly. Since the emergence of initial studies examining the use of neutrophil gelatinase-associated lipocalin (NGAL) and cycle arrest biomarkers, tissue inhibitor metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein (IGFBP7), for early diagnosis of AKI, a vast number of studies have investigated the accuracy and additional clinical benefits of these biomarkers. As proposed by the Acute Dialysis Quality Initiative, new AKI diagnostic criteria should equally utilize glomerular function and tubular injury markers for AKI diagnosis. In addition to refining our capabilities in kidney risk prediction with kidney injury biomarkers, structural disorder phenotypes referred to as "preclinical-" and "subclinical AKI" have been described and are increasingly recognized. Additionally, positive biomarker test findings were found to provide prognostic information regardless of an acute decline in renal function (positive serum creatinine criteria). We summarize and discuss the recent findings focusing on two of the most promising and clinically available kidney injury biomarkers, NGAL and cell cycle arrest markers, in the context of AKI phenotypes. Finally, we draw conclusions regarding the clinical implications for kidney risk prediction.

Acute kidney injury may impede results after transcatheter aortic valve implantation

INTRODUCTION

Severe complications after transcatheter aortic valve implantation (TAVI) are rare due to increasing procedural safety. However, TAVI procedure-related haemodynamic instability and increased risk of infection may affect renal functional reserve with subsequent renal acidosis and hyperkalaemia.

OBJECTIVE

In this study, we investigated incidence, modifiable risk factors and prognosis of acute kidney injury (AKI) and AKI complicated by hyperkalaemia, pulmonary oedema or metabolic acidosis after TAVI.

METHODS

In a retrospective single-centre study, 804 consecutive patients hospitalized during 2017 and 2018 for elective TAVI were included. AKI was defined according to the 'Kidney Disease Improving Global Outcome' (KDIGO) initiative. Variables on co-morbidities, intra-/post-interventional complications and course of renal function up to 6 months after index-hospitalization were assessed. In multivariate regression analyses, risk factors for the development of AKI, complicated AKI, renal non-recovery from AKI and in-hospital mortality were determined.

RESULTS

Incidence of AKI was 13.8% (111/804); in-hospital mortality after TAVI was 2.3%. AKI was an independent risk factor for in-hospital mortality, odds ratio (OR) 10.3 (3.4-31.6), P < 0.001, further increasing to OR = 21.8 (6.6-71.5), P < 0.001 in patients with AKI complicated by hyperkalaemia, pulmonary oedema or metabolic acidosis, n = 57/111 (51.4%). Potentially modifiable, interventional factors independently associated with complicated AKI were infection [OR = 3.20 (1.61-6.33), P = 0.001] and red blood cell transfusion [OR = 5.04 (2.67-9.52), P < 0.001]. Valve type and size, contrast volume and other intra-interventional characteristics, such as the need for tachycardial pacing, did not influence the development of AKI. Eleven of 111 (9.9%) patients did not recover from AKI, mostly affecting patients with cardiac decompensation. In 18/111 (16.2%) patients, information concerning AKI was provided in discharge letter. Within 6 months after TAVI, higher proportion of patients with AKI showed progression of pre-existing chronic kidney disease compared with patients without AKI [14/29, 48.3% versus 54/187, 28.9%, OR = 2.3 (95% confidence interval 1.0-5.1), P = 0.036].

CONCLUSIONS

AKI is common and may impede patient outcome after TAVI with acute complications such as hyperkalaemia or metabolic acidosis and adverse renal function until 6 months after intervention. Our study findings may contribute to refinement of allocation of appropriate level of care in and out of hospital after TAVI.

Postoperative acute kidney injury in adult non-cardiac surgery: joint consensus report of the Acute Disease Quality Initiative and PeriOperative Quality Initiative

Postoperative acute kidney injury (PO-AKI) is a common complication of major surgery that is strongly associated with short-term surgical complications and long-term adverse outcomes, including increased risk of chronic kidney disease, cardiovascular events and death. Risk factors for PO-AKI include older age and comorbid diseases such as chronic kidney disease and diabetes mellitus. PO-AKI is best defined as AKI occurring within 7 days of an operative intervention using the Kidney Disease Improving Global Outcomes (KDIGO) definition of AKI; however, additional prognostic information may be gained from detailed clinical assessment and other diagnostic investigations in the form of a focused kidney health assessment (KHA). Prevention of PO-AKI is largely based on identification of high baseline risk, monitoring and reduction of nephrotoxic insults, whereas treatment involves the application of a bundle of interventions to avoid secondary kidney injury and mitigate the severity of AKI. As PO-AKI is strongly associated with long-term adverse outcomes, some form of follow-up KHA is essential; however, the form and location of this will be dictated by the nature and severity of the AKI. In this Consensus Statement, we provide graded recommendations for AKI after non-cardiac surgery and highlight priorities for future research.

What every Intensivist should know about COVID-19 associated acute kidney injury

Acute kidney injury (AKI) is a serious complication in critically ill patients with COVID-19 with a reported incidence ranging from <5% to >25%. Proposed aetiologies include hypovolemia, hemodynamic disturbance and inflammation but also specific factors like direct viral invasion, microvascular thrombosis, and altered regulation of the renin-angiotensin-aldosterone system. To date, there are no confirmed specific therapies, and prevention and management of AKI should follow established guidelines. Novel therapies specifically targeting COVID-19 related pathologies are under investigation. The incidence of renal replacement therapy (RRT) is variable, ranging from 0-37%. In a pandemic, RRT practice is likely to be determined by the number of patients, availability of machines, consumables and staff, clinical expertise, and acceptable alternatives. Close collaboration between critical care and renal services is essential. In this article, we describe the epidemiology and pathophysiology of COVID-19 associated AKI, outline current management and suggest strategies to provide RRT during a pandemic when resources may be scarce.

COVID-19-associated acute kidney injury: consensus report of the 25th Acute Disease Quality Initiative (ADQI) Workgroup

Kidney involvement in patients with coronavirus disease 2019 (COVID-19) is common, and can range from the presence of proteinuria and haematuria to acute kidney injury (AKI) requiring renal replacement therapy (RRT; also known as kidney replacement therapy). COVID-19-associated AKI (COVID-19 AKI) is associated with high mortality and serves as an independent risk factor for all-cause in-hospital death in patients with COVID-19. The pathophysiology and mechanisms of AKI in patients with COVID-19 have not been fully elucidated and seem to be multifactorial, in keeping with the pathophysiology of AKI in other patients who are critically ill. Little is known about the prevention and management of COVID-19 AKI. The emergence of regional 'surges' in COVID-19 cases can limit hospital resources, including dialysis availability and supplies; thus, careful daily assessment of available resources is needed. In this Consensus Statement, the Acute Disease Quality Initiative provides recommendations for the diagnosis, prevention and management of COVID-19 AKI based on current literature. We also make recommendations for areas of future research, which are aimed at improving understanding of the underlying processes and improving outcomes for patients with COVID-19 AKI.

COVID-19-associated acute kidney injury: consensus report of the 25th Acute Disease Quality Initiative (ADQI) Workgroup

Kidney involvement in patients with coronavirus disease 2019 (COVID-19) is common, and can range from the presence of proteinuria and haematuria to acute kidney injury (AKI) requiring renal replacement therapy (RRT; also known as kidney replacement therapy). COVID-19-associated AKI (COVID-19 AKI) is associated with high mortality and serves as an independent risk factor for all-cause in-hospital death in patients with COVID-19. The pathophysiology and mechanisms of AKI in patients with COVID-19 have not been fully elucidated and seem to be multifactorial, in keeping with the pathophysiology of AKI in other patients who are critically ill. Little is known about the prevention and management of COVID-19 AKI. The emergence of regional 'surges' in COVID-19 cases can limit hospital resources, including dialysis availability and supplies; thus, careful daily assessment of available resources is needed. In this Consensus Statement, the Acute Disease Quality Initiative provides recommendations for the diagnosis, prevention and management of COVID-19 AKI based on current literature. We also make recommendations for areas of future research, which are aimed at improving understanding of the underlying processes and improving outcomes for patients with COVID-19 AKI.

Development, implementation and outcomes of a quality assurance system for the provision of continuous renal replacement therapy in the intensive care unit

Critically ill patients with requirement of continuous renal replacement therapy (CRRT) represent a growing intensive care unit (ICU) population. Optimal CRRT delivery demands continuous communication between stakeholders, iterative adjustment of therapy, and quality assurance systems. This Quality Improvement (QI) study reports the development, implementation and outcomes of a quality assurance system to support the provision of CRRT in the ICU. This study was carried out at the University of Kentucky Medical Center between September 2016 and June 2019. We implemented a quality assurance system using a step-wise approach based on the (a) assembly of a multidisciplinary team, (b) standardization of the CRRT protocol, (c) creation of electronic CRRT flowsheets, (d) selection, monitoring and reporting of quality metrics of CRRT deliverables, and (e) enhancement of education. We examined 34-month data comprising 1185 adult patients on CRRT (~ 7420 patient-days of CRRT) and tracked selected QI outcomes/metrics of CRRT delivery. As a result of the QI interventions, we increased the number of multidisciplinary experts in the CRRT team and ensured a continuum of education to health care professionals. We maximized to 100% the use of continuous veno-venous hemodiafiltration and doubled the percentage of patients using regional citrate anticoagulation. The delivered CRRT effluent dose (~ 30 ml/kg/h) and the delivered/prescribed effluent dose ratio (~ 0.89) remained stable within the study period. The average filter life increased from 26 to 31 h (p = 0.020), reducing the mean utilization of filters per patient from 3.56 to 2.67 (p = 0.054) despite similar CRRT duration and mortality rates. The number of CRRT access alarms per treatment day was reduced by 43%. The improvement in filter utilization translated into ~ 20,000 USD gross savings in filter cost per 100-patient receiving CRRT. We satisfactorily developed and implemented a quality assurance system for the provision of CRRT in the ICU that enabled sustainable tracking of CRRT deliverables and reduced filter resource utilization at our institution.

Clinical adoption of Nephrocheck® in the early detection of acute kidney injury

Acute kidney injury is a common complication of acute illnesses and is associated with increased morbidity and mortality. Over the past years several acute kidney injury biomarkers for diagnostication, decision-making processes, and prognosis of acute kidney injury and its outcomes have been developed and validated. Among these biomarkers, tissue inhibitor of metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7), the so-called cell cycle arrest biomarkers, showed a superior profile of accuracy and stability even in patients with substantial comorbidities. Therefore, in 2014, the US Food and Drug Administration approved the use of the product of TIMP-2 and IGFBP7 ([TIMP-2] × [IGFBP7]), known as cell cycle arrest biomarkers, to aid critical care physicians and nephrologists in the early prediction of acute kidney injury in the critical care setting. To date, Nephrocheck® is the only commercially available test for [TIMP-2] × [IGFBP7]. In this narrative review, we describe the growing clinical and investigational momentum of biomarkers, focusing on [TIMP-2] × [IGFBP7], as one of the most promising candidate biomarkers. Additionally, we review the current state of clinical implementation of Nephrocheck®.

Nephrotoxic medications and acute kidney injury risk factors in the neonatal intensive care unit: clinical challenges for neonatologists and nephrologists

Neonatal acute kidney injury (AKI) is common. Critically ill neonates are at risk for AKI for many reasons including the severity of their underlying illnesses, prematurity, and nephrotoxic medications. In this educational review, we highlight four clinical scenarios in which both the illness itself and the medications indicated for their treatment are risk factors for AKI: sepsis, perinatal asphyxia, patent ductus arteriosus, and necrotizing enterocolitis. We review the available evidence regarding medications commonly used in the neonatal period with known nephrotoxic potential, including gentamicin, acyclovir, indomethacin, vancomycin, piperacillin-tazobactam, and amphotericin. We aim to illustrate the complexity of decision-making involved for both neonatologists and pediatric nephrologists when managing infants with these conditions and advocate for ongoing multidisciplinary collaboration in the development of better AKI surveillance protocols and AKI mitigation strategies to improve care for these vulnerable patients.

Recommendations on Acute Kidney Injury Biomarkers From the Acute Disease Quality Initiative Consensus Conference: A Consensus Statement

IMPORTANCE

In the last decade, new biomarkers for acute kidney injury (AKI) have been identified and studied in clinical trials. Guidance is needed regarding how best to incorporate them into clinical practice.

OBJECTIVE

To develop recommendations on AKI biomarkers based on existing data and expert consensus for practicing clinicians and researchers.

EVIDENCE REVIEW

At the 23rd Acute Disease Quality Initiative meeting, a meeting of 23 international experts in critical care, nephrology, and related specialties, the panel focused on 4 broad areas, as follows: (1) AKI risk assessment; (2) AKI prediction and prevention; (3) AKI diagnosis, etiology, and management; and (4) AKI progression and kidney recovery. A literature search revealed more than 65 000 articles published between 1965 and May 2019. In a modified Delphi process, recommendations and consensus statements were developed based on existing data, with 90% agreement among panel members required for final adoption. Recommendations were graded using the Grading of Recommendations, Assessment, Development and Evaluations system.

FINDINGS

The panel developed 11 consensus statements for biomarker use and 14 research recommendations. The key suggestions were that a combination of damage and functional biomarkers, along with clinical information, be used to identify high-risk patient groups, improve the diagnostic accuracy of AKI, improve processes of care, and assist the management of AKI.

CONCLUSIONS AND RELEVANCE

Current evidence from clinical studies supports the use of new biomarkers in prevention and management of AKI. Substantial gaps in knowledge remain, and more research is necessary.

Quality of care after AKI development in the hospital: Consensus from the 22nd Acute Disease Quality Initiative (ADQI) conference

BACKGROUND

Acute kidney injury (AKI) is independently associated with increased morbidity and mortality. Quality improvement has been identified as an important goal in the care of patients with AKI. Different settings can be targeted to improve AKI care, broadly classified these include the inpatient and outpatient environments. In this paper, we will emphasize quality indicators associated with the management and secondary prevention of AKI in hospitalized patients to limit the severity, duration, and complications.

METHODS

During the 22nd Acute Disease Quality Initiative (ADQI) consensus conference, a multidisciplinary group of experts discussed the evidence and used a modified Delphi process to achieve consensus on recommendations for AKI-related quality indicators (QIs) and care processes to improve patient outcomes. The management and secondary prevention of AKI in hospitalized patients were discussed, and recommendations were summarized.

RESULTS

The first step in optimizing the quality of AKI management is the determination of baseline performance. Data regarding each institution's/center's performance can provide a reference point from which to benchmark quality efforts. Quality program initiatives should prioritize achievable goals likely to have the highest impact according to the setting and context. Key AKI quality metrics should include improvement in timely recognition, appropriate diagnostic workup, and implementation of known interventions that limit progression and severity, facilitating recovery, and mitigating AKI-associated complications. We propose the Recognition-Action-Results framework to plan, measure, and report the progress toward improving AKI management quality.

CONCLUSIONS

These recommendations identified and outlined an approach to define and evaluate the quality of AKI management in hospitalized patients.

Acute kidney injury: Challenges and opportunities

Acute kidney injury (AKI) can be a devastating diagnosis for any patient and can increase mortality during hospitalization. There can be long-term consequences for those who survive the initial insult. This article discusses AKI and its implications for nurses.

Nephrologist Follow-Up Care of Patients With Acute Kidney Disease Improves Outcomes: Taiwan Experience

OBJECTIVES

Acute kidney injury (AKI) and acute kidney disease (AKD) are a continuum on a disease spectrum and frequently progress to chronic kidney disease. Benefits of nephrologist subspecialty care during the AKD period after AKI are uncertain.

METHODS

Patients with AKI requiring dialysis who subsequently became dialysis independent and survived for at least 90 days, defined as the AKD period, were identified from the Taiwanese population's health insurance database. Cox proportional hazard models using death as the competing risk before and after propensity-score matching were applied to evaluate various endpoints.

RESULTS

Among a total of 20 260 patients with AKI requiring dialysis who became dialysis independent, only 7550 (37.3%) patients were followed up with by a nephrologist (F/U_nephrol group) during the AKD period. During a mean 4.04 ± 3.56 years of follow-up, the patients in the F/U_nephrol group were more often administered statin, antihypertensives, angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB), diuretics, antiplatelet agents, and antidiabetic agents. The patients in the F/U_nephrol group had a lower mortality rate (hazard ratio [HR] = 0.87, P < .001) and were less likely to have major adverse cardiovascular events (MACE) (subdistribution HR [sHR] = 0.85, P < .001), congestive heart failure (CHF) (sHR = 0.81, P < .001), and severe sepsis (sHR = 0.88, P = .008) according to the Cox proportional model after adjusting for mortality as a competing risk. During the AKD period, an increase in the frequency of nephrology visits was associated with improved outcomes.

CONCLUSIONS

In this population-based cohort, even after weaning off acute dialysis, only a minority of patients visited a nephrologist during the AKD period. We showed that nephrology follow-up is associated with a decrease in MACE, CHF exacerbations, and sepsis, as well as lower mortality; thus it may improve outcomes in patients with AKD.

Quality of Care for Acute Kidney Disease: Current Knowledge Gaps and Future Directions

Acute kidney injury (AKI) and acute kidney disease (AKD) are common complications in hospitalized patients and are associated with adverse outcomes. Although consensus guidelines have improved the care of patients with AKI and AKD, guidance regarding quality metrics in the care of patients after an episode of AKI or AKD is limited. For example, few patients receive follow-up laboratory testing of kidney function or post-AKI or AKD care through nephrology or other providers. Recently, the Acute Disease Quality Initiative developed a consensus statement regarding quality improvement goals for patients with AKI or AKD specifically highlighting efforts regarding quality and safety of care after hospital discharge after an episode of AKI or AKD. The goal is to use these measures to identify opportunities for improvement that will positively affect outcomes. We recommend that health care systems quantitate the proportion of patients who need and actually receive follow-up care after the index AKI or AKD hospitalization. The intensity and appropriateness of follow-up care should depend on patient characteristics, severity, duration, and course of AKI of AKD, and should evolve as evidence-based guidelines emerge. Quality indicators for discharged patients with dialysis requiring AKI or AKD should be distinct from end-stage renal disease measures. Besides, there should be specific quality indicators for those still requiring dialysis in the outpatient setting after AKI or AKD. Given the limited preexisting data guiding the care of patients after an episode of AKI or AKD, there is ample opportunity to establish quality measures and potentially improve patient care and outcomes. This review will provide specific evidence-based and expert opinion–based guidance for the care of patients with AKI or AKD after hospital discharge.

Machine Learning Model for Risk Prediction of Community-Acquired Acute Kidney Injury Hospitalization From Electronic Health Records: Development and Validation Study

BACKGROUND

Community-acquired acute kidney injury (CA-AKI)-associated hospitalizations impose significant health care needs and contribute to in-hospital mortality. However, most risk prediction models developed to date have focused on AKI in a specific group of patients during hospitalization, and there is limited knowledge on the baseline risk in the general population for preventing CA-AKI-associated hospitalization.

OBJECTIVE

To gain further insight into risk exploration, the aim of this study was to develop, validate, and establish a scoring system to facilitate health professionals in enabling early recognition and intervention of CA-AKI to prevent permanent kidney damage using different machine-learning techniques.

METHODS

A nested case-control study design was employed using electronic health records derived from a group of Chang Gung Memorial Hospitals in Taiwan from 2010 to 2017 to identify 234,867 adults with at least two measures of serum creatinine at hospital admission. Patients were classified into a derivation cohort (2010-2016) and a temporal validation cohort (2017). Patients with the first episode of CA-AKI at hospital admission were classified into the case group and those without CA-AKI were classified in the control group. A total of 47 potential candidate variables, including age, gender, prior use of nephrotoxic medications, Charlson comorbid conditions, commonly measured laboratory results, and recent use of health services, were tested to develop a CA-AKI hospitalization risk model. Permutation-based selection with both the extreme gradient boost (XGBoost) and least absolute shrinkage and selection operator (LASSO) algorithms was performed to determine the top 10 important features for scoring function development.

RESULTS

The discriminative ability of the risk model was assessed by the area under the receiver operating characteristic curve (AUC), and the predictive CA-AKI risk model derived by the logistic regression algorithm achieved an AUC of 0.767 (95% CI 0.764-0.770) on derivation and 0.761 on validation for any stage of AKI, with positive and negative predictive values of 19.2% and 96.1%, respectively. The risk model for prediction of CA-AKI stages 2 and 3 had an AUC value of 0.818 for the validation cohort with positive and negative predictive values of 13.3% and 98.4%, respectively. These metrics were evaluated at a cut-off value of 7.993, which was determined as the threshold to discriminate the risk of AKI.

CONCLUSIONS

A machine learning-generated risk score model can identify patients at risk of developing CA-AKI-related hospitalization through a routine care data-driven approach. The validated multivariate risk assessment tool could help clinicians to stratify patients in primary care, and to provide monitoring and early intervention for preventing AKI while improving the quality of AKI care in the general population.

Renin-angiotensin-aldosterone system inhibition decreased contrast-associated acute kidney injury in chronic kidney disease patients

BACKGROUND/PURPOSE

Chronic kidney disease (CKD) is a risk factor for contrast associated acute kidney injury (CA-AKI). The risk of renin-angiotensin-aldosterone system inhibitor (RASi) use in patients with CKD before the administration of contrast is not clear.

METHODS

In this nested case-control study, 8668 patients received contrast computed tomography (CT) from 2013 to 2018 during index administration in a multicenter hospital cohort. The identification of AKI is based on the Kidney Disease: Improving Global Outcomes (KDIGO) serum creatinine criteria within 48 h after contrast medium used.

RESULTS

Finally, 986 patients (age, 63.36 ± 12.22; men, 72.92%) with CKD (estimated glomerular filtration rate (eGFR) = 35.0 ± 19.8 mL/min/1.73 m²) were eligible for analysis. After the index date, RASi users (n = 315) were less likely to develop CA-AKI (13.65% vs 30.4%, p < 0.001), and had a lower hospital mortality (8.25% vs 19.23%, p < 0.001) compared with non-users. The pre-contrast use of RASi decrease the risk of AKI (OR, 0.342, p < 0.001) and hospital mortality (OR, 0.602, p = 0.045). Even a few defined daily doses (DDDs) of RASi treatment, more than 0.02 prior to contrast CT could attenuate CA-AKI. The hospital mortality was higher in RASi non-users if their eGFR value was more than 17.9 mL/min/1.73 m².

CONCLUSION

RASi use in patients with CKD prior to contrast CT has the potential to mitigate the incidence of AKI and hospital mortality. Even a low dose of RASi will noticeably decrease the risk of AKI and will not increase the risk of hyperkalemia.

Controversies in acute kidney injury: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Conference

In 2012, Kidney Disease: Improving Global Outcomes (KDIGO) published a guideline on the classification and management of acute kidney injury (AKI). The guideline was derived from evidence available through February 2011. Since then, new evidence has emerged that has important implications for clinical practice in diagnosing and managing AKI. In April of 2019, KDIGO held a controversies conference entitled Acute Kidney Injury with the following goals: determine best practices and areas of uncertainty in treating AKI; review key relevant literature published since the 2012 KDIGO AKI guideline; address ongoing controversial issues; identify new topics or issues to be revisited for the next iteration of the KDIGO AKI guideline; and outline research needed to improve AKI management. Here, we present the findings of this conference and describe key areas that future guidelines may address.