Contrast media-induced agents

To protect residual renal function, use doses under 0.3 mmol/kg of gadolinium-based contrast agents Referto ESUR guidelines to avoid contrast medium-induced renal damage (hydration, use small doses of low-osmolar contrast media)... 

Acute reduction in renal perfusion is considered important in the pathophysiology of contrast agent-induced nephrotoxicity. Color-coded duplex sonography has been used in assessing intrarenal vascular resistance in 10 patients (mean age 51 years) after intravenous injection of 100 ml of the low-osmolar contrast medium iopamidol (iodine 300 mg/ml) (182). The resistive index was measured at 1-minute intervals over 10 minutes after injection in each patient. There was a statistically significant rise in resistive index at 2, 3, 4, and 5 minutes after injection, mean values 0.74, 0.75, 0.72, and 0.75... 

In patients with pre-existing renal impairment, hemodialysis did not influence the incidence or outcome of contrast-induced nephropathy, in spite of eliminating contrast agents effectively from the circulation. The same group has now confirmed their previous observation in a bigger study in 30 patients with pre-existing renal impairment (184). Hemodialysis did not influence the incidence or outcome of contrast-induced nephropathy, in spite of effective elimination of contrast medium from the circulation. The failure of hemodialysis to protect against the development of contrast nephropathy is due to the very rapid onset of renal injury after the administration of contrast medium. 

A study from Germany has shown that the antioxidant acetylcysteine plus intravenous saline 0.45% prevented the reduction in renal function induced by contrast agents (190). The authors prospectively studied 83 patients with chronic renal impairment (creatinine clearance under 50 ml/minute). The patients took oral acetylcysteine 600 mg bd for 1 day before and 1 day after the contrast medium. Saline 0.45% was given intravenously at a rate of 1 ml/kg/hour for 12 hours before and 12 hours after 75 ml of iopromide (iodine 300 mg/ml) intravenously. All the patients were encouraged to drink if they were thirsty. A matched control group received placebo and saline. The mean serum creatinine in the control group (42 patients, mean age 65 years) rose from a mean of 212-226 pmol/l 48 hours after contrast injection. In those... 

A report from Italy has suggested that intravenous saline 0.4% before and after administration of the contrast medium, an infusion of dopamine 3 micrograms/kg/ minute for 24 hours after the contrast medium, intravenous furosemide 80 mg 30 minutes before the contrast medium, or intravenous mannitol (20%) 250 ml 1 horn-before and 1 hour after the contrast medium each prevented the reduction in renal function caused by the nonionic agents iobitridol, ioversol, or iodixanol (193). However, the protocol of the study was not described, and previous studies have shown that dopamine, furosemide, and mannitol do not offer good protection against contrast media-induced nephrotoxicity. On the other hand, volume expansion with intravenous saline has been found to offer some protection (190). 

The Royal College of Radiologists. Guidelines with regard to metformin-induced lactic acidosis and x-ray contrast medium agents. 19 March 1999. 

Prevention Several agents have been tried in the past in order to prevent contrast-induced nephrotoxicity. These have all been directed at various proposed methods of causation [SEDA-32, 848]. The most effective to date has been intravenous hydration before and after administration of the iodinated contrast medium, either with 0.9% saline or sodium bicarbonate bicarbonate is superior to saline. 

Bohm I, Medina J, Prieto P, Block W, Schild HH Fixed drug eruption induced by an io-dinated non-ionic X-ray contrast medium a practical approach to identify the causative agent and to prevent its recurrence. Eur Radiol 2007 17 485-489. 

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