New insights into the mechanisms of acute kidney injury in the intensive care unit.

Acute kidney injury is a frequent complication in the intensive care unit that is associated with increased mortality and morbidity. Traditional models consider reductions of global renal blood flow as the cause of acute kidney injury. However, a complex interplay between ischemia-reperfusion injury and inflammation may lead to intrarenal hypoperfusion and acute kidney injury. The role of changes of global renal blood flow as a cause for acute kidney injury remains controversial, especially in sepsis-induced acute kidney injury.