(1434) Renal Replacement Therapy Following IV Contrast Administration in Critically Ill Patients With CKD

Introduction: Renal replacement therapy (RRT) is becoming increasingly common in the ICU. In the setting of critical illness, imaging studies requiring intravenous (IV) administration of iodinated contrast are common for thorough workup and medical evaluation. The effect of iodinated contrast on renal function remains controversial. We aimed to study the incidence of RRT and all-cause ICU mortality among critically ill patients with pre-existing CKD who receive IV iodinated contrast.

Methods: A retrospective cohort study was designed to compare patients exposed to IV contrast agents (exposure group) and those not exposed (control group). The MIMIC IV database was utilized to identify critically ill adults ≥18 years of age with pre-existing CKD Stages 1-4 who required ICU admission for ≥48 hours from 2008 to 2014. Primary outcomes were the need for RRT during hospitalization and ICU mortality. Excluded from the study population were patients with pre-existing CKD Stage 5 requiring regular dialysis prior to admission and those who experienced mortality within 24 hours of arrival.

Results: We included 16,961 critically ill patients with CKD stages 1-4, among whom 673 received IV contrast and 16,288 did not. The median Charlson Comorbidity Index was higher in the non-contrast group (8 vs. 7, p=0.002). ICU length of stay was longer for patients who received contrast (209 hours vs. 129 hours, p< 0.001). Dialysis was required for 7.6% of patients with contrast versus 2.% without (p < 0.001), and ICU mortality was higher in the contrast group (8.5% vs. 4%, p< 0.001).

Multivariate analysis indicated that IV contrast use was independently associated with increased odds of requiring dialysis (OR: 2.85, p< 0.001) and ICU mortality (OR: 1.45, p=0.024). Age and gender were not significant predictors of ICU death, while non-White race was associated with higher odds of both dialysis (OR: 1.57, p=0.005) and ICU death (OR: 1.65, p< 0.001).

Conclusions: These findings suggest that critically ill patients with CKD who receive IV contrast have a higher likelihood of requiring dialysis and experiencing increased ICU mortality. This stands in contrast to existing literature showing no significant association between IV contrast and acute kidney injury (AKI), RRT, and short-term mortality in patients with CKD.