The PREDICT study: a randomized double-blind comparison of contrast-induced nephropathy after low- or isoosmolar contrast agent exposure. AJR Am J Roentgenol. 2008;191:151-157. [PMID: 18562739 DOI: 10.2214/ajr.07.3370]

Contrast-induced acute kidney injury: specialty-specific protocols for interventional radiology, diagnostic computed tomography radiology, and interventional cardiology

Contrast-induced acute kidney injury (AKI) (also known as contrast-induced nephropathy) is an abrupt deterioration in renal function that can be associated with use of iodinated contrast medium. Although the increase in serum creatinine concentration is transient in most cases, contrast-induced AKI may lead to increased morbidity and mortality rates in selected at-risk populations. This review summarizes the findings of a multidisciplinary panel composed of computed tomography radiologists, interventional radiologists, cardiologists, and nephrologists convened to address the specialty-specific issues associated with minimizing the incidence of contrast-induced AKI. As part of this initiative, the panel developed specialty-specific protocols for preventing contrast-induced AKI, taking into account, for example, the variations in patient risk profile, inpatient or outpatient status, and staffing resources that characterize various clinical settings. The 3 protocols, each reflecting a consensus of expert opinion, address the prevention of contrast-induced AKI in interventional radiology, diagnostic computed tomography radiology, and interventional cardiology settings. The protocols are presented in the context of a review of recent guidelines and published reports of trials that discuss contrast-induced AKI and its prevention. The panel reviewed materials retrieved by a PubMed search covering the period January 1990 through January 2008 and used combinations of key words associated with the prevention and treatment of contrast-induced AKI. In addition, the panel reviewed the reference lists of selected articles and the tables of contents posted on the Web sites of selected journals for relevant publications not retrieved in the PubMed searches.

Contrast-induced acute kidney injury: specialty-specific protocols for interventional radiology, diagnostic computed tomography radiology, and interventional cardiology

Contrast-induced acute kidney injury (AKI) (also known as contrast-induced nephropathy) is an abrupt deterioration in renal function that can be associated with use of iodinated contrast medium. Although the increase in serum creatinine concentration is transient in most cases, contrast-induced AKI may lead to increased morbidity and mortality rates in selected at-risk populations. This review summarizes the findings of a multidisciplinary panel composed of computed tomography radiologists, interventional radiologists, cardiologists, and nephrologists convened to address the specialty-specific issues associated with minimizing the incidence of contrast-induced AKI. As part of this initiative, the panel developed specialty-specific protocols for preventing contrast-induced AKI, taking into account, for example, the variations in patient risk profile, inpatient or outpatient status, and staffing resources that characterize various clinical settings. The 3 protocols, each reflecting a consensus of expert opinion, address the prevention of contrast-induced AKI in interventional radiology, diagnostic computed tomography radiology, and interventional cardiology settings. The protocols are presented in the context of a review of recent guidelines and published reports of trials that discuss contrast-induced AKI and its prevention. The panel reviewed materials retrieved by a PubMed search covering the period January 1990 through January 2008 and used combinations of key words associated with the prevention and treatment of contrast-induced AKI. In addition, the panel reviewed the reference lists of selected articles and the tables of contents posted on the Web sites of selected journals for relevant publications not retrieved in the PubMed searches.

Preventing contrast-induced nephropathy in patients with baseline renal dysfunction undergoing coronary angiography

Although contrast-induced nephropathy (CIN) is usually self-limited, it may cause permanent renal injury and even lead to long-term dialysis in patients with preexisting renal impairment. Cardiologists face a dilemma as to whether to alleviate coronary syndromes by coronary intervention or to risk CIN in these patients. Strategies to prevent CIN, including hydration, use of low-osmolal or iso-osmolal contrast media, administration of N-acetylcysteine, and blood purification procedures, were proposed to be effective; however, there are conflicting results. Recently, we found that prophylactic hemodialysis could significantly improve renal survival in patients with advanced renal insufficiency undergoing coronary angiography in a randomized controlled trial. In these patients, fluid supplementation is poorly tolerated and impractical, especially in those with poor heart function. However, the routine use of prophylactic hemodialysis in patients with mild renal insufficiency requires further investigation.

Nephrotoxicity of iso-osmolar iodixanol compared with nonionic low-osmolar contrast media: meta-analysis of randomized controlled trials

PURPOSE

To compare the nephrotoxicity of iso-osmolar iodixanol with that of nonionic low-osmolar contrast media (CM) (LOCM) in randomized clinical trials.

MATERIALS AND METHODS

This meta-analysis was conducted with a systematic search of MEDLINE, EMBASE, BIOSIS, Web of Science, ISI Web of Knowledge, Current Contents Medizin, Cochrane Library (until August 2007), trial registers, conference proceedings, and reference lists to identify studies and with requests from all manufacturers of CM for unidentified studies. Randomized controlled trials assessing serum creatinine levels before and after intravascular application of iodixanol or LOCM were included. The primary outcome measures were the incidence of contrast medium-induced nephropathy (CIN) and change in serum creatinine levels.

RESULTS

Twenty-five trials were included. Iodixanol did not significantly reduce the risk of CIN (relative risk [RR], 0.80; 95% confidence interval [CI]: 0.61, 1.04; weighted mean difference in serum creatinine increase, 0.01 mg/dL [0.88 mumol/L]; 95% CI: -0.01, 0.03). There was no significant risk reduction after intravenous administration of the CM (RR, 1.08; 95% CI: 0.62, 1.89); subgroup with preexisting renal insufficiency (RR, 1.07; 95% CI: 0.56, 2.02) or after intraarterial administration (RR, 0.68; 95% CI: 0.46, 1.01); subgroup with preexisting renal insufficiency (RR, 0.59; 95% CI: 0.33, 1.07). However, in patients with intraarterial administration and renal insufficiency, the risk of CIN was greater for iohexol than for iodixanol (RR, 0.38; 95% CI: 0.21, 0.68), whereas there was no difference between iodixanol and the other (noniohexol) LOCM (RR, 0.95; 95% CI: 0.50, 1.78).

CONCLUSION

Iodixanol is not associated with a significantly reduced risk of CIN compared with the LOCM pooled together. However, in patients with intraarterial administration and renal insufficiency, iodixanol is associated with a reduced risk of CIN compared with iohexol, whereas no significant difference between iodixanol and other LOCM could be found.

Contrast-induced nephropathy: are there differences between low osmolar and iso-osmolar iodinated contrast media?

It is acknowledged that high osmolar contrast media are more nephrotoxic than low (LOCM) or iso-osmolar contrast media (IOCM). However, it remains contentious whether the IOCM are less nephrotoxic in comparison with LOCM. This article reviews published clinical studies that investigated this issue and demonstrates there are no conclusive data to indicate that there is a definite difference in renal tolerance between LOCM and IOCM. All these agents are potentially nephrotoxic in patients with advanced renal impairment. In these patients the smallest possible dose of IOCM or LOCM should be used in addition to adequate hydration to minimize the risk of contrast nephropathy.

Contrast safety in the cancer patient: preventing contrast-induced nephropathy

Cancer patients undergo frequent imaging examinations. Computed tomography (CT) examinations for tumor staging and assessment of treatment response generally require administration of intravascular contrast medium. Iodinated contrast agents for CT are associated with the risk of contrast-induced nephrotoxicity (CIN), particularly in patients with impaired renal function and diabetes. In many cancer patients the risk of complications from intravascular contrast medium administration is compounded by advanced age, dehydration and coadministration of nephrotoxic chemotherapeutic drugs. In this article I review the definition, clinical manifestations, possible mechanisms and risk factors for CIN, and provide recommendations for prevention of this potentially life-threatening complication.