LAUSR

Background Acute kidney injury (AKI) is common following pediatric cardiac transplantation. Since no treatments exist, strategies focus on early identification and prevention. Kinetic glomerular filtration rate (kGFR) was developed to assess renal function in the non-steady state. Although used to predict AKI in adults, kGFR has not been explored in children. Our study examines AKI and the ability of kGFR to identify AKI risk in pediatric heart transplant recipients. Methods One hundred and seventy-five patients under 21 years who underwent cardiac transplantation at Lucile Packard Children’s Hospital between September 2007–December 2017 were included. kGFR 1 was calculated using pre-operative and immediate post-operative creatinines; kGFR 2 was calculated with the first two post-operative creatinines. The primary outcome was AKI as defined by the Kidney Disease: Improving Global Outcomes criteria. Results One hundred and thirty-one (75%) and 78 (45%) patients developed AKI and severe AKI, respectively; 5 (2.9%) required dialysis. kGFR was moderately associated with post-operative AKI risk. The adjusted area under the curve (AUC) for kGFR 1 was 0.72 (discovery) and 0.65 (validation). The AUC for kGFR 2 was 0.72 (discovery) and 0.68 (validation). Conclusions AKI is pervasive in children undergoing cardiac transplant, particularly in the 24 h after surgery. kGFR moderately identifies AKI risk and may represent a novel risk stratification technique. Impact Our research suggests that kGFR, a dynamic assessment of renal function that uses readily available laboratory values, can moderately identify AKI risk in children undergoing cardiac transplantation. Current published studies on kGFR are in adult populations; this study represents the first formal study of kGFR in a pediatric population. kGFR may serve as an early AKI indicator, allowing providers to implement preventative strategies sooner in a patient’s clinical course.