The application of hemoadsorption for hyperbilirubinemia and its impact on bilirubin removal kinetics in critically ill children.

Extracorporeal blood purification (EBP) is increasingly applied for bilirubin removal in critical care setting. We retrospectively reviewed the clinical features of children aged 1 month to 18 years old who received EBP for hyperbilirubinemia and explored the bilirubin removal kinetics by hemoadsorption (HA) in the pediatric intensive care unit of Hong Kong Children's Hospital from 3/2019 to 7/2022. Among the 14 episodes of EBP from six patients with a median age (interquartile range [IQR]) of 9.3(5.5) years old, 57.1% of them received HA, 33.3% received single-pass albumin dialysis (SPAD), and 7.1% received combined SPAD and HA. All HA episodes employed the Cytosorb column. The median (IQR) pre-HA peak total bilirubin level was 406 (254) μmol/L. The saturation duration per HA episode was significantly shorter than the corresponding total treatment duration (8 vs 24 h,  = 0.012), and the median total and effective HA doses were 9.8(6.8) L/kg and 300.0 (163.4) mL/kg/h respectively. The overall bilirubin removal ratio by HA was 44.6 (14.5)%. A higher HA effective dose and a higher pre-HA bilirubin level were both associated with better bilirubin removal. No major EBP-specific complication was encountered. The liver enzymes showed improvement in all children. No patients required liver transplantation. There was no EBP-related mortality, but the overall PICU mortality of the cohort was 50%. HA was a safe and effective modality for bilirubin removal among children. Future studies should investigate the impact of bilirubin removal on clinical outcomes and explore the factors responsible for better removal efficacy.