Creatinine Kinetics and the Definition of Acute Kidney Injury

Acute renal failure definitions have changed dramatically over the last 5 to 10 years as a result of criteria established through the following consensus statements/organizations: RIFLE (Risk, Injury, Failure, Loss of function, End stage renal disease), AKIN (Acute Kidney Injury Network), and KDIGO (Kidney Disease: Improving Global Outcomes). In 2002, the Acute Dialysis Quality Initiative was tasked with the goal of establishing a consensus statement for acute kidney injury (AKI). The first order of business was to provide a standard definition of AKI. Up to this point, literature comparison was challenging as studies lacked uniformity in renal injury definitions. Implementing results into evidence-based clinical practice was difficult. The panel coined the term “acute kidney injury,” encompassing previous terms, such as renal failure and acute tubular necrosis. This new terminology represented a broad range of renal insults, from dehydration to those requiring renal replacement therapy (RRT). This review provides an algorithmic approach to the epidemiology, pathophysiology, diagnosis, prevention, and management of AKI. Also discussed are special circumstances, including rhabdomyolysis, contrast-induced nephropathy, and hepatorenal syndrome. Tables outline the AKIN criteria, most current KDIGO consensus guidelines for definition of AKI, differential diagnosis of AKI, agents capable of causing AKI, treatment for specific complications associated with AKI, and options for continuous RRT. Figures show the RIFLE classification scheme and KDIGO staging with prevention strategies. This review contains 1 management algorithm, 2 figures, 6 tables, and 85 references. Keywords: Kidney, renal, KDIGO, azotemia, critical, urine, oliguria, creatinine, dialysis

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Endocrine Summary

The Brigham Intensive Review of Internal Medicine ◽

10.1093/med/9780199358274.003.0056 ◽

2014 ◽

pp. 549-566

Author(s):

Graham T. McMahon

Keyword(s):

Acute Kidney Injury ◽

Filtration Rate ◽

Hospital Admissions ◽

Kidney Injury ◽

Acute Interstitial Nephritis ◽

Hospitalized Patients ◽

Acute Glomerulonephritis ◽

Creatinine Concentration ◽

Tubular Necrosis ◽

Definition Of

Acute renal failure, now referred to as acute kidney injury (AKI), complicates 5–10% of general hospital admissions and is associated with increased morbidity and mortality and prolonged hospitalizations. The definition of AKI varies, but it is usually defined as an increase in serum creatinine concentration of 25–50% above the baseline, a decline in estimated glomerular filtration rate (eGFR) of 25–50%, or the need for renal replacement therapy. It is now recognized that changes in GFR are delayed manifestations of renal injury, and the development of urinary biomarkers may help to identify AKI earlier in the course of injury. The major causes of AKI in hospitalized patients include prerenal causes (~40%), postrenal causes (~5–10%), and intrinsic diseases affecting blood vessels, glomeruli, or tubules. Of the intrinsic causes, tubular disorders (acute tubular necrosis and acute interstitial nephritis) are the most common etiologies, accounting for 40–50% of all causes of AKI. Acute glomerulonephritis and vascular disorders are rare etiologies of AKI in hospitalized patients (〈5%).

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Definitions, classification, epidemiology, and risk factors of acute kidney injury

10.1093/med/9780199592548.003.0220_update_001 ◽

2018 ◽

Author(s):

Eric A. J. Hoste ◽

John A. Kellum ◽

Norbert Lameire

Keyword(s):

Acute Kidney Injury ◽

Medical Literature ◽

Kidney Injury ◽

Staging System ◽

Acute Kidney Injury Network ◽

Classification Systems ◽

Clinical Settings ◽

Binary Descriptor ◽

Staging Systems ◽

Definition Of

The lack of a precise biochemical definition of acute kidney injury (AKI) resulted in at least 35 definitions in the medical literature, which gave rise to a wide variation in reported incidence and clinical significance of AKI, impeded a meaningful comparison of studies.The first part of this chapter describes and discusses different definitions and classification systems of AKI. Patient outcome and the need for renal replacement therapy are directly related to the severity of AKI, an observation that supports the use of a categorical staging system rather than a simple binary descriptor. The severity of AKI is commonly characterized using the relative changes in serum creatinine and urine output. Recently introduced staging systems including the RIFLE classification and the Acute Kidney Injury Network (AKIN) use these relatively simple and readily available parameters allowing the assignment of individual patients to different AKI stages. More recently, a Kidney Disease: Improving Global Outcomes (KDIGO) workgroup developed a consensus-based AKI staging system drawing elements of both RIFLE and AKIN. The potential pitfalls and limitations of the proposed definitions and classifications are briefly described.The second part of the chapter describes the epidemiology of AKI in different clinical settings; the intensive care unit (ICU), the hospitalized population, and the community. The different spectrum of AKI in the emerging countries is discussed and the most important causes and aetiologies of the major clinical types of AKI, prerenal, renal, and post-renal are summarized in table form. Finally the patient survival and renal functional outcome of AKI are briefly discussed

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Acute kidney injury

10.1093/med/9780199659579.003.0127 ◽

2017 ◽

Author(s):

Edward Sharples

Keyword(s):

Acute Kidney Injury ◽

Early Recognition ◽

Kidney Injury ◽

Epidemiological Studies ◽

Hospitalized Patients ◽

Early Management ◽

Common Causes ◽

Definition Of ◽

End Stage

Acute kidney injury (AKI) is a common, major cause of morbidity and mortality in hospitalized patients, and contributes significantly to length of stay and hence costs. Large epidemiological studies consistently demonstrate an incidence of AKI of 5–18% depending on the definition of AKI utilized. Even relatively small changes in renal function are associated with increased mortality, and this has led to strict definition and staging of AKI. Early recognition with good clinical assessment, diagnosis, and management are critical to prevent progression of AKI and reduce the potential complications, including long-term risk of end-stage renal failure. In this chapter, the pathophysiology, causes, and early management of AKI are discussed. Hypovolaemia and sepsis are the most common causes in hospitalized patients, across medical and surgical specialities. Other common causes are discussed, as well as diagnostic criteria.

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Evidence-based development of a nephrotoxic medication list to screen for acute kidney injury risk in hospitalized children

American Journal of Health-System Pharmacy ◽

10.1093/ajhp/zxz203 ◽

2019 ◽

Vol 76 (22) ◽

pp. 1869-1874 ◽

Cited By ~ 1

Author(s):

Elizabeth Goswami ◽

Richard K Ogden ◽

William E Bennett ◽

Stuart L Goldstein ◽

Richard Hackbarth ◽

...

Keyword(s):

Acute Kidney Injury ◽

Quality Improvement ◽

Injury Risk ◽

Kidney Injury ◽

Quality Improvement Initiative ◽

Evidence Based ◽

Hospitalized Children ◽

Consensus Definition ◽

Medication Exposure ◽

Definition Of

Abstract Purpose Medications are commonly associated with acute kidney injury (AKI). However, in both clinical practice and research, consideration of specific medications as nephrotoxic varies widely. The Nephrotoxic Injury Negated by Just-in-time Action quality improvement collaborative was formed to focus on prevention or reduction of nephrotoxic medication-associated AKI in noncritically ill hospitalized children. However, there were discrepancies among institutions as to which medications should be considered nephrotoxic. The collaborative convened a Nephrotoxic Medication (NTMx) Subcommittee to develop a consensus for the classification of nephrotoxic medications. Summary The NTMx Subcommittee initially included pediatric nephrologists, a pharmacist, and a pediatric intensivist. The committee reviewed NTMx lists from the collaborative and identified changes from the initial NTMx list. The NTMx Subcommittee conducted a literature review of the disputed medications and assigned an evidence grade based on the reported association with nephrotoxicity and the quality of the data. The association between medication exposure and AKI was also determined using administrative data from the Pediatric Health Information Systems database. The NTMx Subcommittee then came to a majority consensus regarding which medications should be included on the list. The subcommittee’s recommendations were presented to the larger collaborative for approval, and consensus was achieved. The list continues to be reviewed and updated annually. Conclusion Formation of a multicenter quality-improvement initiative exposed current limitations as to which medications are considered nephrotoxic in clinical and research settings and presented an opportunity to approach this problem using an evidence-based process. A consensus definition of nephrotoxic-medication exposure was achieved.

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Postoperative Acute Kidney Injury: Focus on Renal Recovery Definitions, Kidney Disease Progression and Survival

American Journal of Nephrology ◽

10.1159/000496611 ◽

2019 ◽

Vol 49 (3) ◽

pp. 175-185 ◽

Cited By ~ 3

Author(s):

Thorir E. Long ◽

Solveig Helgadottir ◽

Dadi Helgason ◽

Gisli H. Sigurdsson ◽

Tomas Gudbjartsson ◽

...

Keyword(s):

Acute Kidney Injury ◽

Kidney Disease ◽

Propensity Score ◽

Matched Control ◽

Kidney Injury ◽

Renal Recovery ◽

University Hospital ◽

Control Group ◽

One Year ◽

Definition Of

Background: The aim of this study was to examine different definitions of renal recovery following postoperative acute kidney injury (AKI) and how these definitions associate with survival and the development and progression of chronic kidney disease (CKD). Methods: This was a retrospective study of all patients who underwent abdominal, cardiothoracic, vascular, or orthopedic surgery at a single university hospital between 1998 and 2015. Recovery of renal function following postoperative AKI was assessed comparing 4 different definitions: serum creatinine (SCr) (i) < 1.1 × baseline, (ii) 1.1–1.25 × baseline, (iii) 1.25–1.5 × baseline, and (iv) > 1.5 × baseline. One-year survival and the development or progression of CKD within 5 years was compared with a propensity score-matched control groups. Results: In total, 2,520 AKI patients were evaluated for renal recovery. Risk of incident and progressive CKD within 5 years was significantly increased if patients did not achieve a reduction in SCr to < 1.5 × baseline (hazard ratio [HR] 1.50; 95% CI 1.29–1.75) and if renal recovery was limited to a fall in SCr to 1.25–1.5 × baseline (HR 1.32; 95% CI 1.12–1.57) within 30 days. The definition of renal recovery that best predicted survival was a reduction in SCr to < 1.5 × baseline within 30 days. One-year survival of patients whose SCr decreased to < 1.5 × baseline within 30 days was significantly better than that of a propensity score-matched control group that did not achieve renal recovery (85 vs. 71%, p < 0.001). Conclusions: These findings should be considered when a consensus definition of renal recovery after AKI is established.

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