Abstract
Introduction:
This study examined whether spectral analysis of the electroencephalogram (EEG) can discriminate between mild and severe hypoxic–ischemic injury in the immature brain.
Results:
Total EEG power was profoundly suppressed after umbilical cord occlusion and recovered to baseline by 5 h after 15-min of occlusion, in contrast with transient recovery in the 25-min (P < 0.05). Power spectra were not different between groups in the first 3 h; α and β power were significantly higher in the 15-min group from 4 h, and Δ and θ power from 5 h (P < 0.05). The 25-min group showed severe neuronal loss in hippocampal regions and basal ganglia at 3 days, in contrast with no/minimal injury in the 15-min group.
Discussion:
EEG power after asphyxia did not discriminate between mild and severe injury in the first 3 h in preterm fetal sheep. Severe subcortical neural injury was associated with persistent loss of high-frequency activity.
Methods:
Chronically instrumented fetal sheep at 0.7 gestation (101–104 days; term is 147 days) received either 15-min (n = 13) or 25-min (n = 13) of complete umbilical cord occlusion. The Δ (0–3.9 Hz), θ (4–7.9 Hz), α (8–12.9 Hz), and β (13–22 Hz) components of the EEG were determined by power spectral analysis. Brains were taken at 3 days for histopathology.
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Keogh, M., Drury, P., Bennet, L. et al. Limited predictive value of early changes in EEG spectral power for neural injury after asphyxia in preterm fetal sheep. Pediatr Res 71, 345–353 (2012). https://doi.org/10.1038/pr.2011.80
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DOI: https://doi.org/10.1038/pr.2011.80
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