The Importance of Brain Activity Monitoring with Integrated EEG Amplitude in Neonates with Early Asphyxia Syndrome

Czech version

Authors: J. Lukášková ¹; Z. Tomšíková ²; Z. Kokštein ¹
Authors‘ workplace: Dětská klinika LF UK a FN Hradec Králové ¹; Neonatologické oddělení, Nemocnice České Budějovice ²
Published in: Cesk Slov Neurol N 2008; 71/104(5): 544-551
Category: Original Paper

Overview

The aim of this study was to confirm the correlation between the type of amplitude-integrated EEG (aEEG) in neonates after perinatal or early postnatal asphyxia and the degree of subsequent hypoxic-ischaemic encephalopathy, and to introduce early aEEG monitoring into clinical practice.

Method and patients:
The aEEG was continually recorded in 45 neonates that had suffered from perinatal asphyxia and 2 neonates with early postnatal asphyxia. Average gestational age was 39 weeks, weight 3147 g, average cord pH was 6.95 and base excess was –17.26. Apgar score in 1st minute was 2, in 5th minute 5 and 10th minute 6. The aEEG traces were recorded with a Cerebral Function Monitor 6000 Olympic Medical and classified according to Hellstrom-Westas. The grade of hypoxic-ischemic encephalopathy was evaluated according to Sarnat-Sarnat classification. The assessment of neurological outcome was not included in this work.

Results:
Hypoxic-ischemic encephalopathy did not develop in 10 out of 47 neonates, 7 newborns had encephalopathy grade I, 15 cases developed encephalopathy grade II and 15 patients showed encephalopathy grade III. All of the neonates who had developed no hypoxic-ischaemic encephalopathy or encephalopathy grade I had “continuous normal voltage” or “discontinuous normal voltage” trace type. The negative predictive value (probability of cases with normal aEEG to develop maximally HIE grade I) was 0.75. All types of traces from “continuous normal voltage” to “flat trace” were recorded in neonates with hypoxic-ischaemic encephalopathy grade II. All cases with encephalopathy grade III showed an abnormal aEEG trace (“burst suppression”, “low voltage” and “flat trace”). The positive predictive value of abnormal aEEG trace to predict the development of HIE grade II or III was 0.92.

Conclusion:
In our study we confirmed the usefulness of aEEG assessment in predicting the development of subsequent hypoxic-ischemic encephalopathy in neonates that have suffered from early asphyxia. Introduction of early non‑invasive EEG monitoring into clinical practice might help to identify cases that could benefit from therapeutic hypothermia.

Key words:
neonate – hypoxic-ischaemic encephalopathy – EEG monitoring – integrated EEG amplitude – hypothermia

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