Infraslow EEG activity in burst periods from post asphyctic full term neonates
Artikel i vetenskaplig tidskrift, 2005

OBJECTIVE: To investigate whether very low EEG frequency activity can be recorded from post asphyctic full term neonates using EEG equipment where the high pass filter level was lowered to 0.05 Hz. METHODS: The time constant of the amplifier hardware was set to 3.2 s in order to enable recordings that equal to a high pass filter cut off at 0.05 Hz. Burst episodes were selected from the EEGs of 5 post asphyctic full term neonates. The episodes were analysed visually using different montages and subjected to power spectrum analysis. Powers in two bands were estimated; 0-1 and 1-4 Hz, designated very low- and low-frequency activity, respectively (VLFA, LFA). RESULTS: In all infants, VLFA coinciding with the burst episodes could be detected. The duration of the VLFA was about the same as that of the burst episode i.e. around 4s. The activity was most prominent over the posterior regions. In this small material, a large amount of VLFA neonatally seemed to possibly be related to a more favourable prognosis. CONCLUSIONS: VLFA can be recorded from post asphyctic full term neonates using EEG equipment with lowered cut off frequency for the high pass filter. SIGNIFICANCE: VLFA normally disregarded due to filtering, is present in the EEG of sick neonates and may carry important clinical information.

Female

Cerebral Palsy/diagnosis/etiology/physiopathology

Newborn

Infant

Diagnostic Errors

Humans

Cerebral Cortex/*physiopathology

Signal Processing

*Action Potentials

Brain/*diagnosis/etiology/*physiopathology

Hypoxia

Artifacts

Computer-Assisted

Asphyxia Neonatorum/*complications

Male

Electroencephalography/*methods

Författare

M. Thordstein

Sahlgrenska universitetssjukhuset

Nils Löfgren

Chalmers, Signaler och system

Anders Flisberg

Göteborgs universitet

Ralph Bågenholm

Göteborgs universitet

Kaj Lindecrantz

Högskolan i Borås

Ingemar Kjellmer

Göteborgs universitet

Clinical Neurophysiology

1388-2457 (ISSN)

Vol. 116 1501-6

Ämneskategorier

MEDICIN OCH HÄLSOVETENSKAP

DOI

10.1016/j.clinph.2005.02.025

PubMed

15953555