Post-contrast acute kidney injury in intensive care unit patients: a propensity score-adjusted study

Jennifer S. McDonald, Robert J. McDonald, Eric E. Williamson, David F. Kallmes, Kianoush Kashani

To examine the association of intravenous iodinated contrast material administration with the subsequent development of post-contrast AKI (PC-AKI), emergent dialysis, and short-term mortality using a propensity score-adjusted analysis of a cohort of intensive care unit (ICU) patients who underwent CT examination. All ICU patients at our institution who received a contrast-enhanced (contrast group) or unenhanced (noncontrast group) CT scan from January 2006 to December 2014 were identified. Patients were subdivided into pre-CT eGFR > 45 and eGFR ≤ 45 subsets and separately underwent propensity score analysis. Rates of KDIGO-defined AKI, dialysis, and mortality were compared between contrast and noncontrast groups. Separate analyses of eGFR ≥ 60, 30-59, and <30 subsets were also performed. A total of 6877 ICU patients (4351 contrast, 2526 noncontrast) were included in the study. Following propensity score adjustment, the rates of AKI (31 vs. 34%, OR .88 (95% CI .75-1.05), p = .15), dialysis (2.0 vs. 1.7%, OR 1.20 (.66-2.17), p = .55), and mortality (12 vs. 14%, OR .87 (.69-1.10), p = .23) were not significantly higher in the contrast versus noncontrast group in the matched eGFR > 45 subset. Significantly higher rates of dialysis (6.7 vs. 2.5%, OR 2.72 (1.14-6.46), p = .0240) were observed in the contrast versus noncontrast group in the matched eGFR ≤ 45 subset. Intravenous contrast material administration was not associated with an increased risk of AKI, emergent dialysis, and short-term mortality in ICU patients with pre-CT eGFR > 45. An increased risk of dialysis was observed in patients with pre-CT eGFR ≤ 45.