Clinical question: Do rates of acute kidney injury (AKI), renal replacement therapy (RRT), or mortality differ between adults receiving contrast-enhanced computed tomography (CT) versus those receiving noncontrast CT?
Background: Published estimates regarding the risk of postcontrast complications are highly variable and recent data show that the risk of postcontrast AKI may be lower than previously suggested.
Study design: Systematic review and meta-analysis..
Setting: Noninterventional studies assessing differences in AKI, new RRT, or mortality among adults who received contrast-enhanced CT, compared with those receiving noncontrast CT.
Synopsis: A search among six databases and Google Scholar from inception through 2016 yielded 28 observational studies meeting inclusion criteria that included 107,335 participants. Twenty-six assessed AKI, 13 assessed need for RRT, and 9 assessed all-cause mortality. Compared with noncontrast CT, contrast-enhanced CT was not significantly associated with AKI (odds ratio, 0.94; 95% confidence interval, 0.83-1.07), RRT (OR, 0.83; 95% CI 0.59-1.16), or all-cause mortality (OR, 1.0; 95% CI 0.73-1.36). The overall risk of bias ranged from low to serious among the included studies. Studies were observational in nature, they were conducted in multiple settings (for example, ICU, emergency department), and the baseline characteristics of included patients were highly variable.
Bottom line: This meta-analysis observed no difference in adverse events between patients receiving contrast-enhanced CT versus those receiving noncontrast CT but should be interpreted with caution given the observational nature of the studies and differing characteristics of the included patients and study settings.
Citation: Aycock RD et al. Acute kidney injury after computed tomography: a meta-analysis. Ann Emerg Med. 2017 Aug 12.
Dr. Simonetti is a hospitalist at the University of Colorado School of Medicine.