Prerenal azotemia and acute tubular necrosis, the two forms of ischemic acute renal failure,
account for more than half the cases of renal failure in hospitalized patients. Yet the
contribution of ischemia is initially unrecognized in many patients with acute renal failure.
This article reviews the renal response to ischemia and the clinical features of and risk
factors for normotensive ischemic acute renal failure.