Moderate to severe neonatal encephalopathy (NE) an incidence of 1-2/1000 live births. MRI scans have the best predictive values for long term outcome but prediction of prognosis by early markers such as amplitude integrated EEG (aEEG) is less accurate in infants undergoing hypothermia.
The objective of the study was to correlate daily aEEG severity score in infants with NE to early MRI severity score.
In this retrospective cohort study neonates over 35 weeks gestation born between 10/06 and 07/15 were included if they were diagnosed with moderate to severe NE, treated with hypothermia, had aEEG monitoring during the first 4 days of life and an MRI scan before hospital discharge. MRI scans and aEEG were categorized as mild/normal, moderate and severely abnormal. Time to sleep cycling was noted on aEEG. Mantel-Haenszel test and LOESS regression were used for statistical analysis.
Thirty-two infants were included in the study. In 20 (63%) MRI scans were normal/mildly abnormal, in 9 (28%) moderately abnormal and in 3 (9%) severely abnormal. Twenty-nine (91%) infants survived to discharge. MRI severity score was significantly associated with aEEG background on the second and third days of life (p=0.001). An increase in the MRI severity score was noted if sleep cycling appeared after the 5th day of life.
Depressed aEEG at the second and third day of life and appearance of sleep cycling beyond the 5th day of life are associated with pathologic MRI and may be associated with increased risk of abnormal outcome.
