Preventing Nephropathy Induced by Contrast Medium

Abstract
A 71-year-old man with type 2 diabetes and hypertension is referred for coronary angiography. Medications include metformin and a thiazide. Before the angiogram, his serum creatinine level is 1.8 mg per deciliter (160 μmol per liter), yielding an estimated glomerular filtration rate of 40 ml per minute per 1.73 m2 of body-surface area. What can be done to reduce the risk that an angiographic contrast agent will worsen his kidney function?