Sleep ontogenesis in early human prematurity from 24 to 27 weeks of conceptional age

Abstract

DREYFUS-BRISAC, C . (1968). Sleep Ontogenesis in Early HuntanPrentaturity from 2 f to 27 Weeks of Comeptual Age. DEWLOPMENTAL PSYCHOSIOLOCY, l(3): 162-169. The spontaneous behavior of 5 previable human prematiiies born between 24 and 27 weeks of gestational age and weighing between 600 and 900 g was studied, between the 3rd and 30th hr of life. Death occurred between the 281h and 120th hr. Body motility, eye movements, respiratory and cardiac rhythnis, chin inyogram, electroencephalogram (EEG), and crying were evaluated by careful observation and by polygraphic recordings for periods of from 1 to 2 hr. A very rich and continuous motility is described corisisting of rapid jerks, cither diffuse or localized, and of slow movements. Rhythmic niovements of the chin or perihuccal area occur in bursts and are particularly striking. T h e paucity of rapid eye movements (REM) is also remarkable. T h c EEG is composed of silent periods interrupted by discontinuous polymorphic activity. The fixation of the cardiac rate, the absence of periodic respiration and of apneic periods are the most important vegetative phenomena. Crying occurs in short periods rarely lasting niore than 20 sec. T h e state of thcse previable preiiiatures cannot be considered as waking; it seems to be a vcry immature state of sleep that differs from both the quiet and the active slcep of full-term newborns. This atypical sleep, which appears to be present in other spccies characterized by a great degree of immaturity at birth, does not give any evidence of c > clic organization.

Heart Rate Variability during Sleep and Wakefulness in Low-Birthweight Infants

“…This fixation of heart rate has been reported in early fetuses [31], in dying fe tuses [15], in premature infants [11,35,36], in deeply comatose patients [33], in infants with idiopathic respiratory distress syndrome [28], and in patholog ical newborns [21,32], None of these reports correlated their data with sleep stages, except for those reported by French workers [11,21]. D reyfus-Brisac [11] observed surprisingly regular heart rates in infants between 24 and 27 weeks' gestational age. In infants after 32 weeks' conceptional age, she re ported that the heart rate was very irregular during about 50% of the tracings recorded during the sleeping state [12].…”

Percutaneous Respiration in the New-Born Infant

“…Term infants were studied in quiet sleep only but preterm infants were studied in active or quiet sleep since transition between these sleep states occurs so frequently [16,17], After a lengthy period o f acclimatisation and sta bilisation, pulmonary oxygen uptake was measured over three consecutive 10-min periods, initially with air in the chamber, then with 90% oxygen, and then …”

Sleep evolution from fetal life to adulthood: respiratory and neurologic aspects

“…Através da monitorização transabdominal da gestante, ele demonstrou a presença de um traçado contí-nuo de baixa voltagem e de ritmo irregular. Desde então, vários autores descreveram a evolução do padrão eletroencefalográfico em prematuros [16][17][18] . Entre 24 e 27 semanas de gestação, o EEG mostra um padrão com períodos de alta voltagem, com predominância ocipital, e ondas lentas com atividade pleomórfica alternando-se com longos períodos de atividade muito deprimida -tracé discontinu (Figura 1).…”

“…Dreifuss-Brisac observou que a associação de movimentos oculares com um padrão eletroencefalográfico específico (sono REM) se dá ao redor de 37 semanas 16 .…”