Acute Kidney Injury (AKI), also referred to as Acute Renal Failure (ARF), is defined by a loss of excretory kidney function that approximately affects 50% of patients admitted to intensive care units (ICUs). The mortality rate due to AKI may be higher in elderly patients, in patients with chronic diseases, such as diabetes or heart disease, and in patients requiring dialysis support during their AKI treatment. In some cases, the mortality rate for AKI can be more than 50%. However, with timely and adequate treatment, the mortality rate for AKI can be significantly reduced. Over the past decade, an important distinction has been made between transient and persistent AKI.