[The influence of neonatal hyperbilirubinemia on neonatal behavior]

Two groups of neonates, 30 cases with hyperbilirubinemia (307.8 +/- 99.86 mumol/L) and 30 normal newborns (control group with bilirubin 80.37 +/- 35.74 mumol/L), were evaluated with Neonatal Behavioral Assessment Scale (NBAS) and followed up at the age of 2 months and 5 months. All cases in the two groups were evaluated with NBAS at ages of 2-3 days, 12-14 days and 26-28 days. The results showed that there were statistically significant differences between the two groups in the aspects of attention and social responsiveness, the ability to modulate state of consciousness, the motor integrity and the reflexes. We also found that while the level of bilirubin was below 205.2 mumol/L, there was no correlation between the level of bilirubin and NBAS (r = -0.095, P > 0.02), but when bilirubin was at or above the level of 205.2 mumol/L, there was significant negative correlation (r = -0.53, P < 0.001) between the two. The follow-up revealed that 9 of 23 jaundiced infants had abnormal auditory reactions or abnormal muscle tonus at the age of 2 months; 8 of the 9 infants recovered, but 1 still had abnormal muscle tonus by the age of 5 months. The study suggests that hyperbilirubinemia above the level of 205.2 mumol/L would affect neonatal behavior and the greater the severity of jaundice, the more significant the influence on neonatal behavior. The effects on some jaundiced infants may last 5 months or more. NBAS is a valuable scale for early detection of mild brain dysfunctions which are less obvious on clinical examination.