An elderly patient is scheduled for a CT scan with and without contrast dye. Whi

1 -- Common nephrotoxins associated with acute tubular necrosis include the aminoglycoside antibiotics and radiologic contrast media. Many other drugs, heavy metals such as mercury and gold, and some common chemicals such as ethylene glycol (antifreeze) are also potentially toxic. The risk for acute tubular necrosis is higher when nephrotoxic drugs are given to older patients or patients with preexisting renal insufficiency, and when used in combination with other nephrotoxins. Dehydration increases the risk by increasing the toxin concentration in nephrons. Monitoring responsiveness and vital signs are important, but do not address the specific risks of this examination. The specific location of the body for the CT scan is not indicated, therefore, it is not known if the patient would need to be kept n.p.o prior to the test.