Rebound in serum bilirubin level following intensive phototherapy.

OBJECTIVES: To document the need for repeated phototherapy (as an index of significant rebound in serum bilirubin levels) following the discontinuation of intensive phototherapy and to compare the use of repeated phototherapy in infants who first received phototherapy during their birth hospitalization with the use of first-time phototherapy on readmission after infants were discharged from their birth hospitalization.

DESIGN: A retrospective review of the medical records of 303 term and near-term newborns treated between January 1996 and December 1998, who received phototherapy in our well-baby nursery during their birth hospitalization (group 1, n = 158) or who had been discharged from the nursery and were readmitted for phototherapy (group 2, n = 144). All infants received intensive phototherapy but were managed by individual attending pediatricians. Rebound measurements were included if a bilirubin level was obtained between 4 and 48 hours after discontinuing phototherapy.

SETTING: Newborn nursery and pediatric ward of a large community hospital.

MAIN OUTCOME MEASURES: The number of infants who received repeated phototherapy and the magnitude of the bilirubin-level rebound.

RESULTS: Thirteen (8.2%) of 158 (95% confidence interval [CI], 3.9-12.4) infants treated with phototherapy before discharge from the nursery (group 1) and only 1 (0.7%) of 144 (95% CI, 0-2.0) infants who first received phototherapy on readmission (group 2) received repeated phototherapy (P =.002). Phototherapy was discontinued when mean +/- SD total serum bilirubin levels were, 10.4 +/- 1.8 mg/dL (178 +/- 31 micromol/L) in group 1 and 12.3 +/- 1.3 mg/dL (210 +/- 22 micromol/L) in group 2. The mean +/- SD increase in the total serum bilirubin levels following rebound was 1.3 +/- 2.0 mg/dL (22 +/- 34 micromol/L) in group 1 and 0.27 +/- 1.46 mg/dL (4.6 +/- 25 micromol/L) in group 2 (P<.001).

CONCLUSIONS: It is not necessary to keep infants in the hospital to check for rebound. However, for infants who require phototherapy during their birth hospitalization and for those with significant hemolytic disease, we recommend obtaining a follow-up bilirubin level 24 hours after discharge. This is probably not necessary in those who are readmitted for phototherapy but, because rare instances of significant rebound have occurred in these infants, additional clinical follow-up is appropriate, particularly if phototherapy is discontinued at higher total serum bilirubin levels than used in this study.