Original Studies Contrast Induced-Acute Kidney Injury following Peripheral Angiography with Carbon Dioxide versus Iodinated Contrast Media: A Meta-Analysis and Systematic Review of Current Literature Saad S. Ghumman, 1 MD, Jonathan Weinerman, 1 BS, Aazib Khan, 1 MD, Mubeen S. Cheema, 1 MD, Marlene Garcia, 1 MD, Daniel Levin, 1 MD, Rajeev Suri, 2 MD , and Anand Prasad, 1 * MD, FACC, FSCAI, RPVI Objective: We conducted a meta-analysis to compare the incidence of acute kidney injury (AKI) with carbon dioxide (CO 2 ) versus iodinated contrast media (ICM). Back- ground: Contrast induced-acute kidney injury (CI-AKI) is a known complication follow- ing endovascular procedures with ICM. CO 2 has been employed as an alternative imaging medium as it is nontoxic to the kidneys. Methods: Search of indexed data- bases was performed and 1,732 references were retrieved. Eight studies (7 observa- tional, 1 Randomized Controlled Trial) formed the meta-analysis. Primary outcome was AKI. Fixed effect model was used when possible in addition to analysis of publication bias. Results: In this meta-analysis, 677 patients underwent 754 peripheral angio- graphic procedures. Compared with ICM, CO 2 was associated with a decreased inci- dence of AKI (4.3% vs. 11.1%; OR 0.465, 95% CI: 0.218-0.992; P 5 0.048). Subgroup analysis of four studies that included granular data for patients with chronic kidney disease (CKD) did not demonstrate a decreased incidence of AKI with CO 2 (4.1% vs. 10.0%; OR 0.449, 95% CI: 0.165–1.221, P 5 0.117). Patients undergoing CO 2 angiography experienced a higher number of nonrenal events including limb/abdominal pain (11 vs. 0; P 5 0.001) and nausea/vomiting (9 vs. 1; P 5 0.006). Conclusions: In comparison to ICM, CO 2 use is associated with a modestly reduced rate of AKI with more frequent adverse nonrenal events. In studies that use CO 2 as the primary imaging agent, the average incidence of AKI remained high at 6.2%—supporting the concept that factors other than renal toxicity from ICM may contribute to renal impairment following periph- eral angiography. V C 2017 Wiley Periodicals, Inc. Key words: contrast agents; angiography; peripheral/renal; acute kidney injury Additional Supporting Information may be found in the online ver- sion of this article. 1 Department of Medicine, Division of Cardiology, The Universi- ty of Texas Health Science Center, San Antonio, Texas 2 Department of Radiology, The University of Texas Health Sci- ence Center, San Antonio, Texas Conflict of interest: Nothing to report. Contract grant sponsor: Freeman Heart Association Endowment for Cardiovascular Disease. *Correspondence to: Anand Prasad, MD, FACC, FSCAI, RPVI, Department of Medicine, Division of Cardiology, Interventional Cardiology, Endovascular Therapy, Vascular Medicine, UT Health Science Center at San Antonio. E-mail: anandprasadmd@gmail.com Received 27 January 2017; Revision accepted 3 March 2017 DOI: 10.1002/ccd.27051 Published online 00 Month 2017 in Wiley Online Library (wileyonlinelibrary.com) V C 2017 Wiley Periodicals, Inc. Catheterization and Cardiovascular Interventions 00:00–00 (2017)