Neonatal hyperbilirubinemia

Having just started a new rotation in the NICU at Maine Medical Center in Portland, Maine, I've already come upon the question of phototherapy several times with unsatisfactory conclusions.  To manage the hyperbilirubinemia plaguing my two charges, twin ex-32 week (ADORABLE!) baby girls, I've done several interweb searches, consulted the all-knowing Harriet Lane Handbook, and conducted an Up-To-Date search with little, if any, helpful guidelines pertaining to these kids. 

The problem is, most bilirubin curves are for 35 week infants and up.  And most guidelines regarding preemies offer suggestions for the first 7 days of life, but not beyond.  So the current therapy is a hybrid of the two guidelines mixed in with a Tablespoon of experience from the unit's neonatologist du jour.  This is a frustrating situation to say the least, not only because some extra thought is required to determine 'to light or not to light', but also because it's not entirely clear if the therapy we're using is really the best treatment for these little girls. 

In light of all the other advances neonatology has made in the last decade-plus, it's realistic to think that some studies will begin to pop up soon with more evidence-based data and guidelines for babies like these who fall between current recommendations.  In the meantime, here are the current guidelines for preemies and full-term infants when it comes to phototherapy treatments for neonatal jaundice:

For infants >35 weeks, guidelines for initiating phototherapy:

• For infants at low risk (≥38 weeks gestation and without risk factors), phototherapy is started at the following TB values.

• 24 hours of age: >12 mg/dL (205 micromol/L)
• 48 hours of age: >15 mg/dL (257 micromol/L)
• 72 hours of age: >18 mg/dL (308 micromol/L)
  
  Infants in this category who have TB levels 2 to 3 mg/dL (34 to 51 micromol/L) below the recommended levels may be treated with fiberoptic or conventional phototherapy at home.

• For infants at medium risk (≥38 weeks gestation with risk factors or 35 to 37 6/7 weeks gestation without risk factors), phototherapy is started at the following TB values.

• 24 hours of age: >10 mg/dL (171 micromol/L)
• 48 hours of age: >13 mg/dL (222 micromol/L)
• 72 hours of age: >15 mg/dL (257 micromol/L)
  
  The threshold for intervention may be lowered for infants closer to 35 weeks and raised for those closer to 37 6/7 weeks.

• For infants at high risk (35 to 37 6/7 weeks gestation with risk factors), phototherapy is initiated at the following TB values.

• 24 hours of age: >8 mg/dL (137 micromol/L)
• 48 hours of age: >11 mg/dL (188 micromol/L)
• 72 hours of age: >13.5 mg/dL (231 micromol/L)
• Reference: http://www.uptodate.com/contents/treatment-of-unconjugated-hyperbilirubinemia-in-term-and-late-preterm-infants?source=search_result&search=neonatal+jaundice&selectedTitle=3%7E52

http://pediatrics.aappublications.org/content/114/1/297.full

And for premature infants: 
Begin phototherapy in infants less than 35 weeks GA and who are less than seven days of age :

GA <28 weeks - TB >5 mg/dL (86 µmol/L)

GA 28 to 29 weeks - TB 6 to 8 mg/dL (103 to 137 µmol/L)

GA 30 to 31 weeks - TB 8 to 10 mg/dL (137 to 171 µmol/L)

GA 32 to 33 weeks - TB 10 to 12 mg/dL (171 to 205 µmol/L)

GA >34 weeks - TB 12 to 14 mg/dL (205 to 239 µmol/L)

• Reference: http://www.uptodate.com/contents/hyperbilirubinemia-in-the-premature-infant-less-than-35-weeks-gestation?source=search_result&search=neonatal+jaundice&selectedTitle=9%7E52

Another useful tool for determining the same, available online and as a mobile app, is BiliTool.  Using the baby's date of birth, date and time of blood sample and total bilirubin level, a risk stratification (ie, "low risk," "moderate risk," etc) is assigned to guide in determining need for phototherapy.  These guidelines however are only intended for infants >35 weeks gestational age as premature infants have been determined to need more aggressive phototherapy protocols.