The aetiopathology of extrahepatic portal vein obstruction is unknown. In retrospective studies, umbilical vein cannulation and sepsis have been alleged to cause portal thrombosis. This prospective study was undertaken to detect whether thrombosis and consequent obstruction of the splenoportal venous system develops after umbilical vein catheterization for exchange transfusion in newborns using Doppler ultrasound. Forty children (M = 24; F = 16) who had undergone exchange transfusion for hyperbilirubinaemia were studied at school age. Maximal duration of the venous umbilical cannulation was 120 min and sepsis did not occur. Clinical, biological and sonographic examinations were normal, except in 3 children. In 2 the left branch of portal vein could not be identified (normal variant).
Conclusion: Our results show that, in these children, umbilical vein catheterization did not lead to development of portal vein thrombosis. However, when other risk factors such as umbilical infection, traumatic catheterization are associated, children should be screened for obstruction of the portal vein.