Incidence and risk factors for vascular complications after pediatric liver transplantation: a retrospective two-center comparative study

Objectives This study aimed to analyze the pattern and risk factors for vascular complications (VC) in 2 pediatric LTx centers, one in Egypt and the other in the UK. Patients and methods A retrospective analysis on children undergoing LTx over the years (2015–2020) in group 1 ( n = 46 patients; all of them underwent living donor LTx) and over the years (2014–2023) in group 2 ( n = 300 patients: 92% were deceased donor LTx and only 8% were living donor LTx). Liver unit database was reviewed in different time periods post-transplant (first week, 4 weeks, 3 months, 6 months, 1 year, 5 years, and 10 years for VC, e.g., hepatic artery thrombosis (HAT) and stenosis (HAS), portal vein thrombosis (PVT) and stenosis (PVS), and hepatic vein thrombosis (HVT)). Results The overall prevalence of vascular complications was comparable between both groups, occurring in 21.7% of patients (10 out of 46 in group 1 and 65 out of 300 in group 2). These complications predominantly manifested during the early postoperative period (within the first month), affecting 13% of group 1 and 9.3% of group 2 patients. HAT emerged as the most frequent vascular complication in both cohorts, present in 3 patients (6.5% in group 1) and 20 patients (6.7% in group 2), followed by PVT (2 patients (4.3%) and 17 patients (5.6%), respectively) and hepatic vein complications (1 patient (2.17%) and 8 patients (2.6%), respectively). Notably, using multivariate logistic regression analysis, HAT showed a significant correlation with recipient weight < 10 kg ( P value 0.019), use of split grafts ( P value 0.024), prolonged cold ischemia time ( P value 0.035), and donor-recipient size mismatch ( P value 0.039). Similarly, PVT was significantly associated with recipients under 10 kg ( P value 0.004), pre-existing PV anomalies ( P value 0.005), split liver grafts ( P value 0.020), donor-recipient size mismatch ( P value 0.015), and reduced intraoperative portal vein flow ( P value 0.028). Biliary atresia was the most common diagnosis among patients with HAT and PVT, followed by metabolic liver disease in HAT. Conclusion Recipients < 10 kg body weight, split graft recipients, and longer cold ischemic times had a higher incidence of vascular complications. A high index of suspicion needs to be maintained in the evaluation of the children with biliary atresia and metabolic liver disease peri-operatively and in long-term follow-up. Trial registration ClinicalTrials.gov, TRN: NCT04104971. Registration date: 01 October 2019.