Contrast Media Not Linked to Kidney Injury, Even in Sepsis Patients
May 29th, 2018
When emergency physicians order CT scans or other imaging that requires IV contrast media, they often balance that decision against a fear that the patient will suffer acute kidney injury.
A study presented at the recent Society for Academic Emergency Medicine Annual Meeting noted that multiple well-controlled, retrospective studies have debunked the link between IV contrast media (CM) and acute kidney injury (AKI). Yet a study team led by Johns Hopkins University School of Medicine researchers noted that adequately controlled analyses of AKI following CM administration have been lacking for subpopulations of patients, including those with sepsis.
That is significant, study authors wrote, because sepsis puts patients at much higher likelihood for AKI. They also referenced some past research suggesting that septic patients who receive CM are at even greater risk.
To test the hypothesis that IV CM administration is independently associated with increased risk for AKI in patients with sepsis, the research team conducted a single-center, retrospective cohort study. As part of that effort, researchers analyzed all patient visits from a large urban academic ED between 2009 and 2014. The focus was on patients who met criteria for sepsis, severe sepsis, or septic shock based on documentation of these diagnoses or of infection and the presence of two or more systemic inflammatory response criteria. The independent variable under investigation was IV CM, with the primary outcome incidence of AKI at 48-72 hours.
Those patients who underwent contrast-enhanced CT (CECT) were compared with control groups who underwent unenhanced CT or no CT. Overall, 4,140 ED visits were included: 1,464 CECT, 976 unenhanced CT, and 1,731 non-CT. Researchers noted that rates of AKI were 7.2% for the contrast-enhanced group vs. 9.4% for the unenhanced CT group and 9.7% for the non-CT group.
No independent risk for AKI associated with IV CM administration (OR = 0.94; 95% CI, 0.72-1.22) was established, researchers reported.
“Unadjusted comparison of populations was suggestive of decreased risk for AKI associated with CM (OR = 0.73; 95% CI, 0.58-0.93), but this effect was abrogated after propensity score matching (OR = 0.99; 95% CI, 0.97-1.02),” study authors explained. “There were no other differences in AKI risk between groups or subgroups stratified by baseline renal function.”
The study expands on a previous Johns Hopkins emergency medicine study, which did not find an association between IV CM use and acute kidney injury during a controlled design study of a broader ED population.