NEW YORK (Reuters Health) – A newly developed prediction tool quantifies a baby’s risk of rebound hyperbilirubinemia, a study shows.
“Phototherapy is a widely used treatment of neonatal hyperbilirubinemia. The American Academy of Pediatrics (AAP) provides guidelines for when to start phototherapy, but little guidance is available for when to discontinue phototherapy,” write Dr. Pearl Chang of Seattle Children’s Hospital in Washington and colleagues.
Dr. Chang explains, “Phototherapy treatment for jaundice is one of the most common reasons why otherwise healthy newborns need to stay longer in the hospital after they're born or need to return to the hospital after birth.”
“Clinicians now have a tool to help them decide when phototherapy can be stopped,” she told Reuters Health by email. “Given a baby's gestational age and age when treatment was started, clinicians can use this prediction tool to calculate the risk of later requiring repeat phototherapy if they were to discontinue treatment at the baby's current bilirubin level. They can decide, in conjunction with the parents, whether that is an acceptable risk or if phototherapy should be continued longer.”
Figure: Infant receiving phototherapy in the Neonatal Unit.
"Phototherapy" by Jim Champion. Published under Creative Commons License with some rights reserved.
As reported in Pediatrics, online February 14, Dr. Chang and colleagues analyzed records of 7,048 infants born from 2012 to 2014 after at least 35 weeks gestation who received inpatient phototherapy before they were two weeks old. Of those, 3.6% had rebound hyperbilirubinemia, defined as the return of total serum bilirubin to levels prior to phototherapy within 72 hours of treatment termination. The average age at the time of rebound hyperbilirubinemia was about 3.3 days.
After adjustment, lower gestational age was associated with higher odds of rebound hyperbilirubinemia, especially in those born at 35 to 37 weeks’ gestation, for whom the odds ratio was >10 compared with those born at 40 weeks’ gestation.
The odds of rebound hyperbilirubinemia also were higher for Asian infants and those whose total serum bilirubin was relatively higher at the end of phototherapy.
The odds were lower in African American infants and those who were older when phototherapy was started. Compared to infants with birth weights of 3,000 to 3,499 grams, infants weighing less than 2,500 grams had lower odds of rebound hyperbilirubinemia.
In addition, infants who received at least four formula feedings had lower odds of rebound hyperbilirubinemia, as did those who continued on home phototherapy after inpatient treatment (OR, 0.62).
After analyzing those and other potential predictors, the team selected three variables for use in a prediction score: gestational age <38 weeks (adjusted odds ratio, 4.7), younger age at initiation of phototherapy (aOR 0.51 per day) and total serum bilirubin relative to the treatment threshold at the end of phototherapy (aOR 1.5 per mg/dL).
Approximately 70% of infants had scores less than 20, which corresponds to a less than 4% probability of rebound hyperbilirubinemia.
Editorialist Dr. Jeffrey Maisels of Beaumont Children’s Hospital in Royal Oak, Michigan, told Reuters Health, “When phototherapy is discontinued, a small percentage of infants (some 5% to 15%) will experience a rebound in the bilirubin level up to the level at which phototherapy was first initiated, and these infants require retreatment.”
“Infants who are more likely to experience rebound include those: (a) who are not born close to full term (38-40 weeks), (b) have an increase in bilirubin levels due to an incompatibility between the baby’s and mother’s blood groups (hemolytic jaundice), and (c) who require phototherapy sooner rather than later after birth,” he said by email.
“Although pediatricians and family physicians have been aware of these risk factors for some time, they have never been quantified in a straightforward and easily-applied formula,” he observed. “When considering the discontinuation of phototherapy, caregivers now have a simple means of calculating the risk of a rebound in the bilirubin level that might require retreatment.”
“If the score is low,” Dr. Maisels concluded, “phototherapy can be stopped and the infant discharged, a thoroughly welcome outcome for families, hospitals, and physicians.”