We present the case of a premature neonate with pericardial effusion secondary to extravasation of total parenteral nutrition from a mispositioned/migrated umbilical venous catheter. Emergency pericardiocentesis was complicated by an intrapericardial thrombus, which was managed conservatively with spontaneous resolution within 24 hours. This case illustrates that the rare complication of an intrapericardial thrombus after pericardiocentesis can be successfully managed conservatively with close monitoring in haemodynamically stable paediatric patients.
