Effect of Contrast-Enhanced CT Brain on Renal Function in Potential Intraarterial Therapy Patients in the Emergency Department.

INTRODUCTION: Timely imaging is the cornerstone of hyperacute stroke management in emergency departments (EDs). However, the potential nephrotoxicity of iodinated contrast media remains a significant concern for clinicians when considering potential candidates for intraarterial therapy (IAT). This study aimed to investigate the effect of contrast-enhanced computed tomography (CT) on renal function among potential IAT candidates in a local ED. METHODS: We conducted a retrospective cohort study of 112 patients at an ED in Hong Kong who underwent contrast-enhanced CT brain for IAT eligibility screening. Renal function was assessed via serum creatinine and estimated glomerular filtration rate (eGFR) at baseline and postprocedure. Subgroup analyses were performed to evaluate the impact of age, preexisting chronic kidney disease (CKD; eGFR < 60 mL/min/1.73 m2), diabetes mellitus (DM), hypertension (HT), and medications on postcontrast renal outcomes. The primary outcome was the incidence of postcontrast acute kidney injury (PC-AKI), defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. RESULTS: The overall incidence of PC-AKI was low at 0.89% (n = 1). Postcontrast analysis revealed an overall statistically significant reduction in mean serum creatinine from 104.97 to 90.26 μmol/L (p = 0.011), corresponding to an improvement in mean eGFR from 70.20 to 75.13 mL/min/1.73 m2 (p < 0.001). Within the CKD subgroup (n = 27), mean eGFR increased by 8.67 mL/min/1.73 m2 (95% CI 3.71, 13.63) (p = 0.001). Due to the low incidence, the study was underpowered to identify risk factors for PC-AKI, and multivariable regression was not feasible. CONCLUSIONS: Contrast-enhanced CT brain for the workup of potential IAT patients was not associated with clinically evident renal deterioration in this single-centered retrospective cohort. Prospective studies with larger sample sizes, standardized timing for blood tests, and systematic assessment of confounders are required to confirm these findings.