The EEG of the early premature

Anderson, Charlotte M.; Torres, Fernando; Faoro, Angelina

doi:10.1016/0013-4694(85)90015-x

Cited by 101 publications

(57 citation statements)

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“…Lengthening of the sleep cycle is apparently occurring during prematurity, before the neonates reach postconceptional term ages. Others have also confirmed these sequential changes in EEG continuity and discontinuity with increasing postconceptional age (9)(10)(11)(12)16).…”

Section: Discussionmentioning

confidence: 74%

“…Several researchers, however, have questioned this assumption based on studies of sleep in preterm infants. Rudimentary state differentiation in terms of motor, EEG discontinuity, and autonomic function have recently been described in early preterm infants (4,(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). Although four well-developed Received February 8, 1993; accepted May 18, 1994.…”

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confidence: 99%

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Maturation of Phasic and Continuity Measures during Sleep in Preterm Neonates

et al. 1994

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Different physiologic measures during EEG sleep peri-discontinuous periods of EEG activity (i.e. quiet sleep). ods in preterm neonates are postulated to change with Sleep efficiency (p < 0.001), maintenance ( p < 0.001), and maturation and reflect functional brain development. For-latency (p = 0.01) also decreased with increasing postconty-three healthy preterm neonates received 3-h EEG sleep ceptional age. Cycle length between two segments of constudies in an environmentally controlled setting. Postcon-tinuous EEG with an intervening period of EEG disconticeptional ages of neonates at each recording session ranged nuity also lengthened with maturation ( p < 0.001). These from 28 to 35 wk. Minute-by-minute analyses of EEG findings are discussed in the context of previously reported discontinuity, motility, arousals, and REM were per-differences in phasic and continuity measures noted beformed. Eight phasic events and continuity measures of tween preterm and full-term infants at matched full-term sleep were tabulated. Data were analyzed using Spearman postco~ceptional ages. Changes in phasic and continuity rank order correlation coefficients. Increases in arousal measures with increasing postconceptional ages reflect numbers ( p < 0.001) and durations ( p < 0.001) were noted maturation of specific neuronal processes of the CNS with age only during continuous periods of EEG activity within a rudimentary sleep cycle of the preterm neonate. The concept of state during early brain ontogenesis of the preterm infant is controversial. It is generally accepted that patterns representing sleep in preterm infants are highly variable (1) and less organized than patterns described for full-term infants (24). Conventional wisdom dictates that organized sleep states do not appear before 31 w k (1, 2) and are not well established until 36 w k postconceptional age (1-6). Several researchers, however, have questioned this assumption based on studies of sleep in preterm infants. Rudimentary state differentiation in terms of motor, EEG discontinuity, and autonomic function have recently been described in early preterm infants (4,(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). Although four well-developed Received February 8, 1993; accepted May 18, 1994. Correspondence and reprint requests: Mark S. Scher, M.D., Developmental Neurophysiology Laboratory, Magee-Womens Hospital, 300 Halket St., Pittsburgh, PA 15213-3180. Supported in part by Grants NSO1110, NS26793, and MOlRR00084, the Twenty-Five Club of Magee-Womens Hospital, and the Scaife Family Fund.'Presented in part at the 7th International Child Neurology Meeting, Buenos Aires, Argentina, November 1992. sleep state segments of the full-term infant are not observed on the EEG recordings of preterm infants, specific physiologic measures may already have an established association during specific segments of the rudimentary EEG sleep cycle.Studies of the maturational trends of polysomnographic measures in asymptomatic, presumably healthy neonates will assist in the documenta...

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Section: Discussionmentioning

confidence: 74%

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confidence: 99%

Maturation of Phasic and Continuity Measures during Sleep in Preterm Neonates

et al. 1994

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“…Since then, others have used less restrictive criteria of no cerebral electrical activity Ͼ30 V (8,18), a method adopted in the present study. Other groups have reported longer interburst intervals (7,8,10,18,20,21). Anderson et al (20) included infants with abnormal outcome (three infants died), and cranial ultrasound examinations were not performed routinely.…”

Section: Discussionmentioning

confidence: 99%

Spectral Analysis of Electroencephalography in Premature Newborn Infants: Normal Ranges

et al. 2005

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Continuous EEG monitoring has not been used widely in neonatal intensive care, especially in the care of extremely premature infants, probably in part because of a lack of a reliable quantitative method. The purpose of this study was to quantify the EEG of the very premature infants just after birth by using spectral analysis and to describe the characteristics of the spectral signal when infants were clinically stable. Digital EEG recordings were performed on 53 infants who were Յ30 wk gestation for 75 min each day during the first 4 d after birth. Artefact was rejected manually after visual inspection of trace. The EEG was analyzed by manual measurement of interburst interval and automatically by spectral analysis using Fast Fourier Transformation. Spectral analysis generated the normal ranges of the relative power of the ␦ (0.5-3.5 Hz), (4 -7.5 Hz), ␣ (8 -12.5 Hz), and ␤ (13-30 Hz) frequency bands, spectral edge frequency, and symmetry. The median (range) relative power of the ␦ band increased significantly from 68% (62-76%) on day 1 to 81% (72-89%) on day 4 (p ϭ 0.001). The interburst intervals became progressively shorter between days 1 [14s (10 -25)] and 3 [8s (6 -12)]; there were no significant differences between days 3 and 4. The relative power of the ␦ band seemed to be the most useful and repeatable spectral measurement for continuous long-term monitoring. However, automatic artefact rejection software needs to be developed before continuous quantitative EEG monitoring can be used in the neonatal intensive care environment. The hemodynamic status of extremely premature infants is particularly labile during the first days after birth. Intensive interventions for such infants are intended to maintain an adequate tissue oxygen supply, particularly to the brain. Because clinical management is aimed at preserving cerebral integrity in these infants, it would be helpful to have some form of continuous neuromonitoring to guide clinical interventions. EEG provides a useful, noninvasive technique for monitoring cerebral electrical activity, and advances in digital technology have made it possible to record high-quality EEG even in an electrically noisy intensive care environment and have done away with the necessity of using large amounts of recording paper. However, interpretation of the EEG is generally considered to be highly specialized, and this is at least one reason that continuous EEG monitoring is not used widely in neonatal intensive care.There are three major issues to be considered for the automatic and reliable analysis of the EEG signal of premature infants and for data to be presented in a manner that is useful to clinicians. First, the EEG of these infants consists predominantly of high-amplitude slow waves (1,2). Bell et al. (3) showed that the relative power of slow waves with frequency Ͻ1 Hz might be as high as 90% in infants at 28 wk gestation. A recent study using DC EEG on infants between 34 and 37 wk gestation found that the spontaneous EEG activity of sleeping preterm infants consiste...

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Section: E64mentioning

confidence: 98%

“…6,24,25 Similarly, the interburst interval, a surrogate measure of EEG discontinuity, was reported to decrease as GA increases. 5,6,24,25 Interestingly, in the present study, periods of continuous aEEG activity were found in preterm infants as early as 23 weeks of gestation. Hayakawa et al, 6 using 8-channel conventional EEG, also found brief episodes of continuous activity as early as 23 weeks' GA. Connell et al 25 found brief periods of continuous activity at 26 weeks' GA. Other authors did not find continuous activity at these early GAs.…”

Section: E64mentioning

confidence: 98%

Reference Values for Amplitude-Integrated Electroencephalographic Activity in Preterm Infants Younger Than 30 Weeks’ Gestational Age

et al. 2004

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ABSTRACT. Objective. To prospectively investigate the development of amplitude-integrated electroencephalographic (aEEG) activity during the first 2 weeks of life in neurologically normal and clinically stable preterm infants <30 weeks' gestational age (GA).Patients and Methods. Infants with a GA of <30 weeks admitted to the neonatal intensive care unit of the Vienna University Children's Hospital (Vienna, Austria) were studied prospectively by using aEEG and cranial ultrasound. Clinically stable infants without clinical or sonographic evidence of neurologic abnormalities were eligible for inclusion in the reference group. The distribution of 3 background aEEG activity patterns (discontinuous low-voltage, discontinuous high-voltage, and continuous), presence of sleep-wake cycles, and number of bursts per hour in the reference group were determined by visual analysis.Results. Seventy-five infants (median GA: 27 weeks; range: 23-29 weeks) were eligible for inclusion in the reference group and had aEEG recordings during the first 2 weeks of life available. Analysis of aEEG background activity showed that with higher GA the relative amount of continuous activity increased while discontinuous patterns decreased. The number of bursts per hour decreased with increasing GA. Cyclical changes in aEEG background activity resembling early sleep-wake cycles were observed in all infants.Conclusions. Normal values for aEEG background activity were determined in preterm infants <30 weeks' GA. Clinically stable and neurologically normal preterm infants exhibit at least 2 different patterns of aEEG activity. There is a correlation between the GA and the relative duration of continuous aEEG activity. A dvances in neonatal intensive care during the last decades have led to an increased survival rate of extremely low birth weight infants. However, neurologic and developmental disability is still common among survivors. 1 Prevention of brain injury in these patients has become one of the main goals of modern neonatology. Continuous monitoring of neonatal brain function may aid in the identification of risk factors and patients at increased risk for neurologic morbidity. Early recognition and modification of potentially harmful environmental factors may prevent secondary brain injury.Conventional electroencephalography (EEG) is one of the most useful tools for intermittent and continuous assessment of brain function and prediction of neurologic outcome in term infants and children. 2-4 However, conventional EEG has limitations in its application for extremely low birth weight infants. Registration and interpretation of conventional EEG in this age group are difficult because of the electrical interferences on the neonatal intensive care unit, the large volume of data generated during a longer recording, and the need for 24-hour availability of a skilled examiner experienced in EEG of preterm infants. Further, data on normal EEG patterns in extremely premature infants are still limited. 5,6 Recently, amplitude-integrated EEG (aEEG) pro...

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The EEG of the early premature

Cited by 101 publications

References 8 publications

Maturation of Phasic and Continuity Measures during Sleep in Preterm Neonates

Maturation of Phasic and Continuity Measures during Sleep in Preterm Neonates

Spectral Analysis of Electroencephalography in Premature Newborn Infants: Normal Ranges

Reference Values for Amplitude-Integrated Electroencephalographic Activity in Preterm Infants Younger Than 30 Weeks’ Gestational Age

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