Cry analysis in infants with Rh haemolytic disease

The influence of hyperbilirubinaemia on the infants' cries and the feasibility of the use of cry analysis for the early identification of developing kernicterus were studied by analyzing the cries of 100 healthy one-day-old infants and 31 infants with Rh haemolytic disease of the newborn (Rh-HDN) by using sound spectrographic methods. The newborn infants with Rh-HDN were divided into three subgroups according to the findings in a neurological examination: an evident group (10 infants), a transient group (13 infants) and an asymptomatic group (8 infants) and followed up until one year of age. Cry recording and a neurological examination were carried out once for each of the healthy one-day-old infants and twice a day during the first week of life for the infants with Rh-HDN, and thereafter once a day until discharged and at the ages of 1 and 3 months. Additional neurological examinations were performed on the Rh-HDN infants at the ages of 6 and 12 months. Bilirubin determination was carried out in connection with the cry recordings during the first week of life. The effect of blood exchange transfusion on the cry sound was investigated in infants with a bilirubin level above 250 mumol/l (n = 12) and below this level (n = 15) before the procedure. An electroencephalography (EEG) was recorded once during the neonatal period and once during the follow-up. The cries of the healthy infants were used to develop a cry score comprising 16 characteristics (latency, duration of phonation, maximum and minimum pitch of fundamental frequency, occurrence and maximum pitch of shift, glide, melody form, biphonation, furcation, noise concentration, voice quality, double harmonic break, glottal plosives, vibrato and glottal roll), which was then applied to the analysis of the cries of the 31 infants with Rh-HDN. In addition, maximum pitch of fundamental frequency, furcation and combination of biphonation and/or furcation were studied. The cry score and maximum pitch of fundamental frequency increased most obviously in the infants in the evident group as compared with the values after birth in the various subgroups and with the values of the healthy one-day-old infants or the infants in the asymptomatic group day by day. Both parameters also increased in the asymptomatic group between days 2 and 3 as compared with the initial value after birth and with the healthy infants.(ABSTRACT TRUNCATED AT 400 WORDS)