1. The definition of acute kidney injury and its use in practice
Mark E. Thomas, Caroline Blaine, Anne Dawnay, Mark A.J. Devonald, Saoussen Ftouh, Chris Laing, Susan Latchem, Andrew Lewington, David V. Milford, Marlies Ostermann 
Kidney International 
Volume 87, Issue 1, Pages (January 2015)
DOI: /ki
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2. Figure 1
A hypothetical example of real-time glomerular filtration rate (GFR) and creatinine values before and during an episode of acute kidney injury (AKI). There is a single insult to the kidneys with an abrupt drop in GFR (a ‘ramp decrement’21,22). This shows creatinine values in the months before the episode, from which a baseline value will be selected (see text). Often creatinine values at the onset of illness are not available. Creatinine peaks on day 4 with a rise of about 115% (stage 2 AKI). Note the lag between the changes in GFR, compared with the later creatinine rise and recovery.
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3. Figure 2
Mortality (AKIN versus RIFLE). The figure shows the ratio of odds ratios (RORs) for each stage of AKI within RIFLE and AKIN. A ROR >1 indicates that AKIN is a better predictor compared with RIFLE. For example, Lopes30 had odds ratios for mortality of 2.01 for RIFLE I and 2.71 for AKIN 2. This results in a ROR of 1.35 in favor of AKIN, as shown with 95% confidence intervals. AKI, acute kidney injury; AKIN, AKI Network; CI, confidence interval; RIFLE, Risk, Injury, Failure, Loss, and End-stage renal disease; sCr, serum creatinine.
Reproduced by permission of the National Institute of Health and Care Excellence.23
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4. Figure 3
Factors affecting serum creatinine interpretation in possible acute kidney injury (AKI). Many factors can cause an acute increase (left panel) or decrease in creatinine, often making the confident diagnosis of AKI difficult. The estimation of GFR to determine baseline status is also affected by many factors (right panel). Creatinine generation is reduced with lower muscle mass, which will blunt any rise in creatinine with AKI. Assay interferences are more pronounced at normal than at elevated levels of creatinine. Good laboratory practices should routinely detect hemolysis, icterus, and delayed separation, preventing the release of erroneous results. Note blood creatinine is eliminated by glomerular filtration but also by tubular secretion.57 *Edematous states: cirrhosis, the nephrotic syndrome, and heart failure. DKA, diabetic ketoacidosis; eGFR, estimated glomerular filtration rate.
Kidney International  , 62-73DOI: ( /ki )
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