Contrast-induced nephropathy in the critically ill patients

Abstract

A growing number of imaging procedures requiring intravenous administration of iodinated contrast media are performed in the intensive care unit (ICU). Renal toxicity of contrast media added to the multiple renal injuries suffered by the critically ill patients may influence the outcome. The incidence of contrast-induced nephropathy (CIN) in the ICU is difficult to determine because of so many definitions used. Applying the definition of the Acute Kidney Injury Network, about 10–20% of ICU patients receiving iodinated contrast media will develop CIN. In addition to patient’s severity assessed by the Sequential Organ Failure Assessment score, few other ICU-specific risk factors have been identified. The independent effect of contrast media on the kidney function of patients with multiple factors of renal injury is difficult to evaluate and, in the context of emergency imaging, the scarce comparative studies of patients who are either undergoing or not undergoing iodinated contrast-media infusion did not report any difference in the incidence of acute kidney insufficiency. Nevertheless, the independent effect of contrast media, even if minimal, is likely to influence critically ill patients’ outcome, given the poor prognosis of acute kidney insufficiency in this population. Thus, strategies based on the risk/benefit ratio assessment and including hypovolemia correction and preventive drug administration are considered in the light of recent international guidelines.