Contrast-induced acute kidney injury: how should at-risk patients be identified and managed?

Contrast-induced acute kidney injury (CIAKI) refers to a sudden deterioration in renal function associated with the use of iodinated contrast media. CIAKI can lead to increased morbidity and mortality. Risk of CIAKI is low in the general population but increased in patients with risk factors, which include chronic kidney disease (particularly secondary to diabetes mellitus) and advanced age. Screening for risk factors and implementation of prevention practices in at-risk patients is recommended. Patients at risk of CIAKI because of chronic kidney disease can be identified by serum creatinine measurement, although, preferably, this should be applied to estimate glomerular filtration rate; screening questionnaires or risk scoring can also identify at-risk patients. Current best practice calls for intravenous periprocedural volume expansion in at-risk patients, but this is not practical in all clinical settings. No pharmacological approach has been demonstrated to offer consistent protection. Volume/dose of contrast agent should be the lowest needed to achieve a diagnostic result. The use of iso-osmolar contrast media is recommended for high-risk patients, because recent controlled clinical trials in coronary procedure settings have shown a lower nephrotoxicity of iodixanol, as compared with several low-osmolar contrast agents. However, additional studies involving a larger selection of iso- and low-osmolar contrast media are needed, particularly with intravenous use for computed tomography scans, if their use in this patient population is to be optimized.