Fluid Overload and Graft Injury Following Pediatric Liver Transplantation: A Single-Center Analysis

<b>Background:</b> We aimed to compare graft injury and complications after liver transplantation in children with higher versus lower fluid balance. <b>Methods:</b> In a cohort of 79 pediatric liver transplant recipients, we analyzed the associations of decreases in alanine aminotransferase (ALT) and bilirubin (delta ALT, delta bilirubin) with fluid balance in the first six postoperative days and associations of fluid balance with vascular complications and mean ALT one year after the transplantation. <b>Results:</b> Patients who developed vascular complications had significantly higher mean cumulative fluid balance during the first three postoperative days, as well as higher mean fluid balance on postoperative days 0 (POD0) and 2 (POD2) (<i>p</i> < 0.05), compared to those without complications. A negative correlation was observed between fluid balance and delta ALT on POD2. Additionally, patients with a cumulative fluid balance exceeding 200 mL/kg during the first three postoperative days had higher mean ALT levels one year after transplantation (<i>p</i> = 0.03). <b>Conclusions:</b> Fluid overload was associated with vascular complications and showed correlations with markers of graft injury. Prospective studies are needed to validate these findings and further clarify the role of fluid balance in pediatric liver transplantation.