Hyperbilirubinemia in the late preterm newborn

Today we are taking a closer look at another complications experienced by the late preterm newborn: hyperbilirubinemia.  As  you remember we were talking about hypos: too little of something; now we are looking in the other direction, at too much bilirubin in the blood stream and in the brain.  Kernicterus is the condition that can lead to encephalopathy and long term neurological damage. 

A few reasons why this population is at a higher risk are the late development of the hepatic and neurological systems.  Even at term, the neurological system is not totally developed.  This opens the brain to damage more easily than a brain that is fully developed.  The immaturity of the liver is also a factor; it is inefficient in filtering the blood and removing the bilirubin.

Here we have a small baby that usually does not feed well, so is a bit more dehydrated, with a higher risk of hyperbilirubinemia and a higher risk of brain injury and add into it bruising from birth and incompatible blood types between mother and baby.  This scenario will result in a prolonged hospitalization.

Another concern with hyperbilirubinemia is when phototherapy is required, smaller babies with less fat stores have more difficulty maintaining  a normothermic state without the use of external heart sources.  Think about all of the consequences that you may not have considered when caring for a full term newborn with the same diagnosis.

The best way to prevent this is monitoring of serum bilirubin levels, assuring that there is an adequate intake with a supplementation of mother's pumped breast milk or donor breast milk, monitoring output as bilirubin is excreted in the urine and stool and accurate assessments of the newborns color and activity levels.  There is always another worry as well; pain during frequent heelsticks for bilirubin monitoring.

Tomorrow we will look at pain in the late preterm newborn, the effects that repeated pain has on an underdeveloped brain and interventions that can help prevent this stress and pain.