Effect Of Moderate Hyperbilirubinemia On Orienting Responses And Cry In Term Infants

Brazelton auditory orienting responses and acoustic cry patterns were evaluated in 10 moderately jaundiced term infants, (BR-15.2±2.5 mg/dl, Mean±S.D.) and 11 non-jaundiced infants (BR-4.1±1.1 mg/dl). The groups did not differ in birthweight, gestational or postnatal age, or 5 min. Apgar score. Jaundiced infants scored lower on auditory orienting items, (4.7±1.25 vs 5.64±0.55, p<0.02) and on the global orientation cluster (4.96±0.92 vs 5.9±0.53, p<0.01). Cries were recorded during blood sampling, and analyzed by computing the log magnitude spectrum in 25 msec blocks for each cry unit; summary measures were computed across the 25 msec blocks of each cry unit. In jaundiced infants, the first cry utterance showed an increase in average first formant during dysphonation (AvDF1-1876±376 Hz vs 1434±470 Hz, p<0.05), and in the summation of first formant during dysphonation (SumDF1-2102±324 Hz vs 1192±786 Hz, p<0.005). 9 of 10 jaundiced and 4 of 11 non-jaundiced infants had episodes of hyperphonation, and jaundiced infants had greater variability (S.D.) in the maximum fundamental frequency of hyperphonation (Max HFo) for the entire cry (p=0.03 for S.D. Max HFo vs non-jaundiced infants). In summary, moderate hyperbilirubinemia decreases the global capability for orienting responses, and increases the frequencies and variability of some acoustic cry characteristics in term newborns.