Phototherapy for Neonatal Jaundice
Key Points
- Phototherapy is the primary treatment for neonatal hyperbilirubinemia (jaundice) — it converts insoluble bilirubin into water-soluble isomers that are excreted in stool and urine.
- Serum bilirubin >12 mg/dL typically requires treatment.
- The infant must wear only a diaper with eye patches — maximum skin exposure maximizes therapeutic effect.
- Temperature monitoring every 2 hours is required — phototherapy lights can elevate body temperature dangerously.
- Turn off lights before serum bilirubin sampling — ultraviolet exposure degrades bilirubin in the tube.
Pathophysiology of Neonatal Jaundice
Jaundice results from elevated bilirubin in the blood, which deposits in skin and sclera. Bilirubin is produced from the breakdown of fetal red blood cells. Unconjugated bilirubin binds to albumin and is transported to the liver, where it is conjugated with glucuronic acid (via the enzyme UGT) to become water-soluble.
Neonates are vulnerable because:
- Fetal RBCs have a shorter lifespan (70-90 days vs. 120 days)
- Neonatal liver enzyme activity is immature
- Enterohepatic circulation increases bilirubin reabsorption when feedings are insufficient
Types of Neonatal Jaundice
| Type | Onset | Bilirubin Level | Notes |
|---|---|---|---|
| Physiologic jaundice | After first 24 hours | Peaks days 2-4 | Normal; resolves by day 5-7 in term infants |
| Pathologic (nonphysiologic) | Within first 24 hours | Above normal for age | Requires earlier treatment; Rh/ABO incompatibility, metabolic disorders, sepsis |
| Breastfeeding jaundice | First week | >12 mg/dL in 13% of breastfed infants | Insufficient milk intake; resolve by increasing feeds |
| Breast milk jaundice | After day 5-7 | 5-10 mg/dL (up to 20-30 mg/dL) | Beta-glucuronidase in breast milk; resolves over weeks to months |
Kernicterus Risk
Untreated severe hyperbilirubinemia causes kernicterus — bilirubin-induced brain injury. Early signs include lethargy, poor feeding, high-pitched cry, and hypotonia. Advanced signs include seizures and opisthotonus.
Indications
- Serum or transcutaneous bilirubin (TCB) >12 mg/dL generally requires treatment
- Phototherapy threshold varies by gestational age, postnatal age, and risk factors — follow provider orders and hospital policy
- TCB monitoring preferred (noninvasive); serum bilirubin by heel stick if confirmation needed
Phototherapy Procedure
Setup
- Obtain provider order for phototherapy
- Obtain phototherapy unit (bili lights or bili blanket for home use) per facility protocol
- Obtain opaque eye patches (phototherapy goggles) — sized appropriately for infant
- Obtain diaper (only covering genital area)
Nursing Implementation
- Place infant under bili lights in incubator, thermoregulated environment, or open crib
- Apply eye patches over closed eyes before placing under lights — prevents retinal damage
- Cover genital area only with diaper — maximize skin exposure for therapeutic effect
- Ensure light source is positioned per manufacturer specifications
Monitoring During Phototherapy
| Assessment | Frequency | Notes |
|---|---|---|
| Skin and eye assessment | Every 2 hours during feeding breaks | Remove infant from lights for feeding |
| Temperature | Every 2 hours | Phototherapy elevates body temperature — watch for hyperthermia |
| Serum bilirubin | Per orders (typically q4-6h) | Turn off lights before collection — UV degrades bilirubin in sample |
| Feeding | Every 2-3 hours (8-12 feedings/day) | Breastfeeding encouraged; adequate intake reduces enterohepatic circulation |
| Stool and urine output | Each diaper change | Phototherapy increases bilirubin excretion; expect looser stools |
Lights Off Before Bilirubin Sample
Both conjugated and unconjugated bilirubin are photo-oxidized when exposed to white or ultraviolet light. Phototherapy must be turned OFF during serum bilirubin specimen collection.
Parent-Infant Interaction
- Remove infant from lights every 2 hours for feeding and bonding
- Eye covers may be removed during periods outside the lights for parent-infant eye contact
- Eye patches must be replaced when infant is returned to phototherapy
- Educate parents that brief periods outside the lights are safe and beneficial for bonding
Parent Education for Home Bili Blanket
- Position infant skin directly against the bili blanket (no clothing between skin and blanket)
- Monitor temperature; call provider if temp >99°F rectally or <97°F rectally
- Continue breastfeeding every 2-3 hours (8-12 feedings/day)
- Expose maximum skin surface area — remove diaper during blanket use when safe
- Keep scheduled follow-up appointments for bilirubin monitoring
Related Concepts
- birth-related-complications — Phototherapy is a primary intervention for neonatal hyperbilirubinemia from ABO/Rh incompatibility.
- care-of-common-problems-in-the-newborn — Phototherapy protocol in newborn jaundice management.
- neonatal-jaundice — Pathophysiology of bilirubin metabolism in the newborn.
- breastfeeding-support-and-lactation-education — Adequate breastfeeding frequency prevents worsening jaundice.
- reproductive-system — Newborn physiologic transition context.
Self-Check
- Why must phototherapy lights be turned off before collecting a serum bilirubin sample?
- What is the purpose of eye patches during phototherapy, and when can they safely be removed?
- A neonate’s temperature rises to 100.2°F during phototherapy. What is the nursing priority?