When should phototherapy be stopped? A pilot study comparing two targets of serum bilirubin concentration

The objective of this study was to compare the outcome of two groups of jaundiced newborns randomized to one of the two targets of total serum bilirubin (TSB) for phototherapy discontinuation.

Infants treated with phototherapy were assigned to two groups: in the 'high-threshold' group, phototherapy was interrupted when TSB decreased to >/=1 mg/dL (17 micromol/L) below the limit requiring phototherapy and in the 'low-threshold' group when TSB decreased to >/=3 mg/dL (51 micromol/L) below the same limit.

Fifty-two infants were enrolled, 25 in the high- and 27 in the low-threshold group. Phototherapy duration was significantly shorter in the high- than in the low-threshold group (22.3 +/- 13 vs. 27.6 +/- 12 h, respectively, p = 0.03). Length of hospital stay was 84+/-30 h in the high- and 94 +/- 24 h in the low-threshold group (p = 0.05). Additional phototherapy was required in 20% of the high- versus 18% of the low-threshold group (p = 0.58). In the presence of haemolysis or G6PD deficiency, 28% of the infants required re-phototherapy and 8.3% when such factors were absent (p = 0.06).

Phototherapy duration may be shortened by using higher TSB limits for interruption. When hyperbilirubinaemia is accompanied by risk factors, the infants should be followed for longer periods, since some of them will need re-phototherapy.