Sleep State and Respiration in Newborn Infants Undergoing Phototherapy

Abstract

In 13 jaundiced newborn infants polygraphic recordings were done during phototherapy and 1-4 days thereafter. Analysis of respiration was performed by calculating mean respiratory rate during REM- and NREM-sleep and by constructing breath-to-breath interval histograms during REM-sleep.
In REM-sleep, there was only a slight increase of respiratory rate during phototherapy to 58.4 ± 12.9 per min., as compared to 55.4 ± 8.0 per min. without phototherapy. However, in NREM-sleep, mean respiratory rate was increased significantly from 42.4 ± 10.6 per min. to 57.9 ± 23.6 per min., p < 0.0025.
During NREM-sleep without phototherapy, there was a significant negative correlation between serumbilirubin and respiratory rate (0.75, p < 0.01), which was not present with phototherapy and not all detectable during REM-sleep.

Phototherapy with white or blue light has been introduced in the treatment of neonatal jaundice several years ago. However, its mode of operation cannot be considered completely understood until today (Cohen and Ostrow 1980).
Numerous investigations have dealt with possible variations of neuropsychological parameters during phototherapy. Increased irritability (von Bauer 1978, Telzrow et al 1980), poorer scores on orientation items (Telzrow et al 1980), absolutely or relatively prolonged REM-sleep duration (Palm et al 1972, v. Bernuth and Janssen 1974), increased density of rapid eye movements (v. Bernuth and Janssen 1974), immature EEG-patterns (v. Bernuth and Janssen 1974) and increased heart rate and respiratory rate (v. Bernuth and Janssen 1974, Oh et al 1976) have been noted. Palm and Althoff(1971) reported a significant decrease of bilirubin-level associated apneas in premature infants during irradiation with white light.
Several pathogenetic factors have been discussed to explain the observed alterations. They include the high bilirubin-concentration (Telzrow et al 1980), possible toxic actions of the photo-degradation products of bilirubin, disturbance of biological rhythms, mediated by the pathway retina-hypothalamus-pineal body-anterior pituitary (Wurtmann and Cardinali 1976), and finally the effect of child's separation from the mother (Telzrow et al 1980).

During the past years knowledge has increased about the central regulation of respiration during sleep and wakefulness. We studied in a more detailed investigation the respiratory patterns in newborns undergoing phototherapy. In a previous study we reported alterations of sleep-patterns in those same infants (Palm et al 1972).

Key words

Polygraphy - Respiratory control - Phototherapy - Newborn respiratory - Newborn sleep