Pharmacological strategies for treatment of AKI have shown little efficacy in previous studies. Thus, recent studies have aimed to evaluate novel plasma and urinary biomarkers for early diagnosis of AKI, based on the hypothesis that outcomes may improve if AKI were identified and treatment initiated earlier. Urinary IL-18 and NGAL have been shown to be predictive markers of AKI after cardiopulmonary surgery in a pediatric population with a variety of congenital heart defects. This ultimately reduced detection time from 40 hours with conventional serum creatinine assays, to 4-6 hours with urinary IL-18 and NGAL. Serum Cystatin C has also been shown to be as reliable as serum creatinine in predicting kidney filtration levels, particularly for subjects with reduced muscle mass such as a population with congenital heart disease.