Development of sleep–wakefulness rhythm in premature babies

Abstract

The aims of this study were: (1) to investigate the evolution of the sleep pattern in preterm newborns during their first month of life; (2) to assess the influence of light-dark on the sleep pattern; and (3) to compare this pattern with that of full-term newborns. The population consisted of 60 healthy, preterm newborns and 63 full-term newborns, divided into four age groups, 1 week apart, throughout the first month of life. Preterm newborns were further divided into five groups according to conceptional (corrected) age. An observer took note every 30 min, for 24 h, of sleep or wakefulness in every case. The average sleeping time in preterm groups according to postnatal age remained unchanged during the first month of life: 17.57 h on day 1 and 17.15 h on day 28. When the preterm infants were re-grouped according to conceptional age, average daily sleep was 17.86 h at 32 weeks and 15.22 h at 37 weeks. The full-term newborns had an average daily sleep of 14.78 h on day 1 and 11.94 h on day 28, with a decrease throughout week 4 of life (p < 0.001). The decrease in daily sleeping time in the full-term groups, took place at the expense of the daylight span, where there was a decrease throughout the first month of life (p < 0.01). There were no differences in preterm newborns during the light and dark phases. A progressive synchronization of sleep to the light-dark was seen in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Circadian Changes of Heart Rate in West Syndrome

“…These variables were also similar to those from healthy infants belonging to control groups of our previous reports on the subject (Ardura et al 1995(Ardura et al , 1997a.…”

Neurological maturation of late preterm infants at 34 wk assessed by amplitude integrated electroencephalogram

“…We did not combine the aEEG with observations of movement, behavior or rapid eye movements to characterize sleep, wakefulness or transitions between these states. Although sleep-wake states can be identified in preterm infants (20), cohorts studied are usually stable without morbidities of prematurity (21,22). We examined the aEEG and specifically the number of cycles as a neurophysiologic marker to determine if it could indicate neurological maturation for infants of a single week of gestation.…”

Twenty-four-hour and Ultradian Rhythmicities in Healthy Full-Term Neonates: Exogenous and Endogenous Influences

“…3), leads to the conclusion that the babies, certainly by week 4, were responding directly to the light/dark cycle (see also, D' Souza et al, 1992). Presumably, such changes reflect neurological development of both waking and sleep processes [see also, Anders and Keener, 1995;Ardura et al, 1995;D'Souza et al, 1992;Hellbrugge, 1977;Honnebier et al, 1989;Hoppenbrouwers et al, 1982;Prechtl and Lenard, 1968;Sitka, 1988); why they appeared to influence the cardiovascular rhythms less (see Fig. 3) is not clear, but this has been observed before .…”