gratefully acknowledges the following sponsors that make our initiatives possible: Abbott, Amgen, Belo Foundation, Coca-Cola Company, Dole Food Company, Genzyme, Hoffmann-LaRoche, JC Penney, NATCO—The Organization for Transplant Professionals, NKF—Board of Directors, Novartis, Robert and Jane Cizik Foundation, Shire, Transwestern Commercial Services, and Wyeth. KDIGO is supported by a consortium of sponsors and no funding is accepted for the development of specific guidelines. DISCLAIMER While every effort is made by the publishers, editorial board, and ISN to see that no inaccurate or misleading data, opinion or statement appears in this Journal, they wish to make it clear that the data and opinions appearing in the articles and advertisements herein are the responsibility of the contributor, copyright holder, or advertiser concerned. Accordingly, the publishers and the ISN, the editorial board and their respective employers, office and agents accept no liability whatsoever for the consequences of any such inaccurate or misleading data, opinion or statement. While every effort is made to ensure that drug doses and other quantities are presented accurately, readers are advised that new methods and techniques involving drug usage, and described within this Journal, should only be followed in conjunction with the drug manufacturer’s own published literature. SUPPLEMENTARY MATERIAL Appendix F: Detailed Methods for Guideline Development. Supplementary material is linked to the online version of the paper at http://www.kdigo.org/clinical_practice_guidelines/AKI.php Table 1 | Implications of the strength of a recommendation Implications Grade* Patients Clinicians Policy Level 1 ‘‘We recommend’’ Most people in your situation would want the recommended course of action and only a small proportion would not. Most patients should receive the recommended course of action. The recommendation can be evaluated as a candidate for developing a policy or a performance measure. Level 2 ‘‘We suggest’’ The majority of people in your situation would want the recommended course of action, but many would not. Different choices will be appropriate for different patients. Each patient needs help to arrive at a management decision consistent with her or his values and preferences. The recommendation is likely to require substantial debate and involvement of stakeholders before policy can be determined. 18 Kidney International Supplements (2012) 2, 13–18 chapter 1.2 Section 2: AKI Definition Kidney International Supplements (2012) 2, 19–36; doi:10.1038/kisup.2011.32 Chapter 2.1: Definition and classification of AKI INTRODUCTION AKI is one of a number of conditions that affect kidney structure and function. AKI is defined by an abrupt decrease in kidney function that includes, but is not limited to, ARF. It is a broad clinical syndrome encompassing various etiologies, including specific kidney diseases (e.g., acute interstitial nephritis, acute glomerular and vasculitic renal diseases); non-specific conditions (e.g, ischemia, toxic injury); as well as extrarenal pathology (e.g., prerenal azotemia, and acute postrenal obstructive nephropathy)—see Chapters 2.2 and 2.3 for further discussion. More than one of these conditions may coexist in the same patient and, more importantly, epidemiological evidence supports the notion that even mild, reversible AKI has important clinical consequences, including increased risk of death.2,5 Thus, AKI can be thought of more like acute lung injury or acute coronary syndrome. Furthermore, because the manifestations and clinical consequences of AKI can be quite similar (even indistinguishable) regardless of whether the etiology is predominantly within the kidney or predominantly from outside stresses on the kidney, the syndrome of AKI encompasses both direct injury to the kidney as well as acute impairment of function. Since treatments of AKI are dependent to a large degree on the underlying etiology, this guideline will focus on specific diagnostic approaches. However, since general therapeutic and monitoring recommendations can be made regarding all forms of AKI, our approach will be to begin with general measures. Definition and staging of AKI AKI is common, harmful, and potentially treatable. Even a minor acute reduction in kidney function has an adverse prognosis. Early detection and treatment of AKI may improve outcomes. Two similar definitions based on SCr and urine output (RIFLE and AKIN) have been proposed and validated. There is a need for a single definition for practice, research, and public health. 2.1.1: AKI is defined as any of the following (Not Graded): K Increase in SCr by X0.3 mg/dl (X26.5 lmol/l) within 48 hours; or K Increase in SCr to X1.5 times baseline, which is known or presumed to have occurred within the prior 7 days; or K Urine volume o0.5 ml/kg/h for 6 hours. 2.1.2: AKI is staged for severity according to the following criteria (Table 2). (Not Graded) 2.1.3: The cause of AKI should be determined whenever possible. (Not Graded) RATIONALE Conditions affecting kidney structure and function can be considered acute or chronic, depending on their duration. AKI is one of a number of acute kidney diseases and disorders (AKD), and can occur with or without other acute or chronic kidney diseases and disorders (Figure