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

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.