**1. Introduction**

Prevalence of acute kidney injury (AKI) was evaluated at 22% in hospital settings in a large meta-analysis of 3.5 million patients and raised up to 57% when admitted to intensive care units (ICUs) [1, 2]. The incidence of dialysis-requiring AKI has increased by 10% yearly from 2000 to 2009 in the United States [3]. Hence, renal replacement therapy (RRT) is widely used in modern acute care settings as a supportive management of severe acute kidney injury (AKI) and multiorgan failure (MOF). While RRT in chronic end-stage kidney disease (ESRD) is mostly reserved for nephrologists, its prescription in context of acute-care settings is shared between many medical specialties.

The first section reviews the basic principles and characteristics of the different modalities used in ICUs nowadays. Then, the main section is meant to guide clinicians in evidence-based RRT prescribing by examining the most relevant body of literature published in the last decade. Indications, timing of initiation, modality choice, dosing, anticoagulation, and discontinuing RRT are discussed. Finally, some specific and more challenging scenarios are briefly covered as well as other pragmatic aspects.
