Threshold for initiation of phototherapy in infants with non-haemolytic hyperbilirubinaemia.

The effect of initiating phototherapy at three different bilirubin concentrations in infants with physiological jaundice was studied in 98 clinically jaundiced term infants. Phototherapy was initiated at levels of 170, 257 and 300 mumol/l in groups A, B and C respectively. There was no difference between the groups in terms of days in hospital and bilirubin levels at entry or at exit from the study. Of group A, 97% received phototherapy v. 47% and 18% in groups B and C respectively. Peak bilirubin in those infants in group C receiving phototherapy was 318 mumol/l v. 282 mumol/l and 229 mumol/l in groups A and B. Two group C infants suffered complications of hyperbilirubinaemia. Rebound hyperbilirubinaemia was noted in infants with more severe jaundice after cessation of phototherapy. The threshold for toxicity in non-haemolytic hyperbilirubinaemia may be higher than the still widely accepted 340 mumol/l value, but pending definitive studies phototherapy will continue to be initiated at levels of greater than 257 mumol/l in term infants with hyperbilirubinaemia.