Acute Kidney Injury Requiring Dialysis After Pediatric Heart Transplant

Background Acute kidney injury (AKI) is a common complication of pediatric heart transplant, with a subset of patients developing severe AKI requiring dialysis (AKI‐D). We aimed to identify the epidemiology, risk factors, and outcomes of postoperative AKI‐D in pediatric heart transplant recipients. Methods We retrospectively identified all pediatric first‐time, single‐organ heart transplants at our institution from 2014 to 2022. Postoperative AKI was defined as AKI within 2 weeks of transplant. Unadjusted and adjusted logistic regression were used to identify characteristics associated with AKI‐D, and unadjusted time‐to‐event analyses were used to determine the association between AKI‐D and survival free of kidney failure. Results Among 177 patients included, 116 (66%) developed postoperative AKI of any stage, including 13 (7%) who developed AKI‐D with median time from transplant to dialysis initiation of 6 days (IQR 3–13). In adjusted models, increased cardiopulmonary bypass time (OR 1.19, 95% CI 1.04–1.37, per 15 min increase in bypass time) and higher weight at transplant were associated with higher odds of AKI‐D, whereas patient demographics and pretransplant kidney function were not associated with AKI‐D. AKI‐D was associated with greater mortality during initial hospitalization (46% vs. 1%, p < 0.001) and a lower rate of survival free of kidney failure. Conclusions The incidence of AKI‐D after pediatric heart transplant was 7%, with extended cardiopulmonary bypass time associated with postoperative AKI‐D even in adjusted models. Further research is needed to improve the prediction and management of AKI‐D in this population.