Therefore, prevention of acute encephalopathy remains the justification for the prevention, detection and treatment of severe hyperbilirubinemia. The collaborative perinatal project, examining 54,795 live births in the United States, was unable to find any consistent association between peak TSB concentrations below critical levels and IQ or other adverse outcomes. This remains controversial however, if there are bilirubin concentrations at which subtle cerebral injury can occur, the thresholds are unknown. Milder degrees of hyperbilirubinemia not leading to a clinical presentation of acute encephalopathy may also be neurotoxic and cause less severe long-term complications. In addition, some infants with severe hyperbilirubinemia are found to have sepsis, but both sepsis and hyperbilirubinemia are common in the neonatal period, and sepsis appears to be uncommon in the well-appearing infant with severe hyperbilirubinemia. All of the reasons for the variable susceptibility of infants are not known however, dehydration, hyperosmolarity, respiratory distress, hydrops, prematurity, acidosis, hypoalbuminemia, hypoxia and seizures are said to increase the risk of acute encephalopathy in the presence of severe hyperbilirubinemia, although reliable evidence to confirm these associations is lacking. Even with concentrations greater than 500 µmol/L, there are still some infants who will escape encephalopathy. More than three-quarters of the infants in the United States’ kernicterus registry (between 19) had a TSB concentration of 515 µmol/L or greater, and two-thirds had a concentration exceeding 600 µmol/L. Above this level, the risk for toxicity progressively increases. Acute encephalopathy does not occur in full-term infants whose peak TSB concentration remains below 340 µmol/L and is very rare unless the peak TSB concentration exceeds 425 µmol/L. It is estimated that 60% of term newborns develop jaundice and 2% reach a TSB concentration greater than 340 µmol/L. The prevention, detection and management of jaundice in otherwise healthy term and late preterm newborn infants remain a challenge, partly because jaundice is so common and kernicterus is so rare in comparison. Critical hyperbilirubinemia – a TSB concentration greater than 425 µmol/L during the first 28 days of life.Severe hyperbilirubinemia – a total serum bilirubin (TSB) concentration greater than 340 µmol/L at any time during the first 28 days of life.Chronic bilirubin encephalopathy – the clinical sequelae of acute encephalopathy with athetoid cerebral palsy with or without seizures, developmental delay, hearing deficit, oculomotor disturbances, dental dysplasia and mental deficiency.Acute bilirubin encephalopathy – a clinical syndrome, in the presence of severe hyperbilirubinemia, of lethargy, hypotonia and poor suck, which may progress to hypertonia (with opisthotonos and retrocollis) with a high-pitched cry and fever, and eventually to seizures and coma.Kernicterus – the pathological finding of deep-yellow staining of neurons and neuronal necrosis of the basal ganglia and brainstem nuclei.Key Words: 35 weeks’ gestation Hyperbilirubinemia Jaundice Preterm newborn Term newborn Background and epidemiology Definitions of terms as used in this statement Guidelines for the prediction, prevention, identification, monitoring and treatment of severe hyperbilirubinemia are presented. Early discharge of the healthy newborn infant, particularly those in whom breastfeeding may not be fully established, may be associated with delayed diagnosis of significant hyperbilirubinemia. Critical hyperbilirubinemia is uncommon but has the potential for causing long-term neurological impairment. Hyperbilirubinemia is very common and usually benign in the term newborn infant and the late preterm infant at 35 to 36 completed weeks’ gestation. KJ Barrington, K Sankaran Canadian Paediatric Society Fetus and Newborn CommitteeĪbridged version: Paediatr Child Health 2007 12(Suppl B):1B-12B Abstract
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |