Cerebral Function Monitoring During the First Week of Life in Extremely Small Low Birthweight (ESLBW) Infants

Abstract

In order to evaluate the usefulness of early continuous EEG-monitoring in very preterm neonates, recordings with a Cerebral Function Monitor (CFM) were made prospectively in 31 ESLBW infants with birthweights below 901 grams, during their first week of life. The CFM background activity was, as expected from EEG studies, dominated by a suppression-burst pattern in 94% of the infants. Some infants had periods with more continuous EEG activity or suppression-burst changing into continuous. Patterns similar to sleep-wake cycling (SWC) were identified in infants with gestational ages as low as 24 weeks. The level of the CFM-background activity was mainly influenced by the presence and severity of intracranial hemorrhage (ICH), but also by medications such as phenobarbital. Epileptiform activity (EPA) was only found in infants with ICH, and was identified in 75% of these infants. Of the infants with EPA, 87% had periods with subclinical EPA, although 47% had both clinical and subclinical seizures. The presence of more continuous activity and SWC were indicators of a favourable outcome, whereas electrocerebral inactivity predicted an unfavorable outcome. The prognostic estimates of mortality and neurologic outcome were similar for early CFM recording (positive predictive value 69-100%) and cranial ultrasound scan (positive predictive value 71-100%). The monitoring of cerebral electrical activity also provided immediate and clinically useful information during the intensive care of these ESLBW infants. Further studies on the causal relation between EPA and the development of ICH should be performed before definite conclusions can be drawn concerning any preventive effect from anticonvulsive treatment of clinical/subclinical seizures.

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

“…Cycles have been demonstrated in infants studied between 25 and 30 wk by the presence of alternating intervals of EEG discontinuity (23). The presence of cycles on aEEG has been reported as early as 26 wk (24,25). However, determination of cycles is difficult in extremely preterm neonates, since much of the aEEG tracing is discontinuous.…”

Electroencephalography and brain damage in preterm infants

“…Electrographical seizure activity, often subclinical, is common and affects approximately 60-70 % of infants during the development of IVH 20,21,22 . Although many previous studies indicated that an association between PRSW and IVH, some studies showed that PRSW did not seem to be associated with IVH and were more often observed with white matter injury PVL 20 .…”

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

“…17,18 Information on aEEG activity in extremely premature infants is still limited. 19 Therefore, the objective of this study was to prospectively investigate the development of aEEG activity in preterm infants Ͻ30 weeks of gestation. We have already published preliminary results on the occurrence of sleep-wake cycles in 38 preterm infants from this cohort.…”

“…These 10-minute epochs were classified into 3 pattern categories as follows (Fig 1): • Sleep-wake cycles were defined as cyclical sinusoidal variations of both amplitude and continuity of aEEG activity with a minimum epoch duration of 20 minutes. 19,20 Bursts were defined as amplitudes Ͼ100 V. …”