Early EEG power predicts MRI injury in infants with hypoxic-ischemic encephalopathy

Abstract

Early TEP is a reliable predictor of moderate-severe MRI injury in encephalopathic infants undergoing TH and may enable early stratification of infants who may benefit from adjuvant therapeutic interventions.

Prognostic Value of Continuous Electroencephalogram Delta Power in Neonates With Hypoxic-Ischemic Encephalopathy

“…In general, the central-parietal regions (C3, C4, P3, or P4) demonstrated the highest discriminatory power at the majority of time periods, and this is in agreement with an early study. 23 The delta power in favorable vs adverse outcome groups as stratified by encephalopathy grade at presentation are shown in Figure 3 (moderate) and Figure 4 (severe). For neonates with moderate encephalopathy, results were similar to those for the overall cohort, with significant differences from 9 to 90 hours of life except during five 3-hour periods (45-48 hours, 57-60 hours, 66-69 hours, 75-78 hours, and 78-81 hours).…”

“…Total power has been used in other studies as a prognostic indicator in HIE. 9,23 However, total power can be affected by electrical and ventilator artifacts common in the ICU setting. Specifically, a subharmonic of a powerline artifact may appear at 20 Hz or below and affect the characterization of total power.…”

“…The power spectral analysis approach used in this study and elsewhere does not suffer from this limitation. 8,9,23,35 Future work is needed to compare the reliability of alternative quantitative EEG metrics as prognostic indicators in HIE.…”

“…Sedation and seizure medications might have dampened the EEG variability. 23 We did not have detailed information on the dose and timing of these medications in order to evaluate their effects on delta power. Taking these aspects into consideration would strengthen future studies.…”

Predictors of Long-Term Neurodevelopmental Outcome of Hypoxic-Ischemic Encephalopathy Treated with Therapeutic Hypothermia

“…72 Quantitative EEG variables such as total EEG power calculated at 9 hours of life, taking a threshold of < 10 μV 2 , helped in early stratification of a high-risk cohort who subsequently had brainstem injury, which is uniformly associated with poor prognosis and high mortality. 73 Bedside availability of EEG makes it a beneficial tool in HIE to predict the course of illness. Several different classification systems of EEG based on voltage, continuity, frequency, symmetry, and sleep-wake cycling demonstrate wide variability in interpretation and diagnostic cut-offs, suggesting the need for standardized classification that accounts for both injury evolution and time of recording to improve predictive ability.…”