Newborn Hyperbilirubinemia Assessment Calculator

Hyperbilirubinemia is an elevated concentration of bilirubin in the blood. It commonly appears as jaundice during the first days after birth because newborn red blood cells turn over rapidly while the liver is still developing its ability to process bilirubin. Most jaundice is temporary, but a sufficiently high unconjugated bilirubin level can enter brain tissue and cause acute bilirubin encephalopathy or kernicterus. Safe assessment therefore depends on the measured level, the infant's precise postnatal age, gestational maturity, clinical condition, and how quickly the value is changing. This calculator plots total serum bilirubin against an age-specific approximation of the Bhutani risk zones. The reference boundaries are interpolated between representative values from 12 through 120 hours and classify results as low, low-intermediate, high-intermediate, or high risk. It also shows an educational phototherapy screening threshold that rises with age and is lowered for gestational age below 38 weeks or reported neurotoxicity risk factors. This simplified threshold is deliberately identified as an estimate; it is not a substitute for the detailed curves and tables in current pediatric guidance. Enter postnatal age in completed hours rather than calendar days. Use a total serum bilirubin result in milligrams per deciliter and confirm that the sample time matches the age entered. Gestational age should be the best obstetric estimate. Birth weight is collected because it is clinically relevant to the overall newborn assessment even though the simplified risk-zone interpolation does not independently change its numeric boundary. Neurotoxicity risks may include hemolysis, sepsis, significant clinical instability, or low albumin, but only a qualified clinician can establish whether those conditions are present. Any infant with visible jaundice in the first 24 hours, rapidly rising bilirubin, poor feeding, lethargy, abnormal tone, fever, or other illness needs prompt professional assessment regardless of this output. Transcutaneous screening may require serum confirmation, and treatment decisions depend on current national guidance, local protocols, repeat measurements, direct versus total bilirubin, feeding and weight history, and discharge follow-up reliability. Do not delay care because a calculated zone appears reassuring. This tool is for education and structured discussion with a pediatric professional, not diagnosis, discharge clearance, or independent treatment selection.