The Primary aim of this study is to develop quantitative metrics for the use of continuous electroencephalography (cEEG) during Therapeutic Hypothermia (TH). The goal of the metrics is to determine the duration and need for the use of limited EEG resources during TH.

TH is well-recognized as the standard of care for neonates with Hypoxic Ischemic Encephalopathy (HIE). Seizures are a common concern in the setting of HIE. cEEG is an exceptional diagnostic tool in the assessment of seizures, especially in neonates where a significant proportion of seizures are subclinical. American Academy of Pediatrics recommends monitoring neonates on TH with cEEG for an unspecified period of time. Institutional practices vary, but a significant number prefer cEGG throughout the duration of TH and rewarming. Thus, posing a significant burden on economic and human resources.

A retrospective analysis of the EEG data gathered from neonates undergoing TH, on cEEG at Norton Children’s Hospital (NCH) from 2016-2018, to assess the background and timing of recorded EEG abnormalities and seizures.  

EEG data from 88 neonates was analyzed. Of the neonates with a normal or mildly abnormal EEG background, 96% had no seizures on day 1, day 2 and 3. 93% of them continued to remain seizure free even through the rewarming phase. Neonates who had a moderate to severely abnormal EEG background- 19% had szs on day 1 followed by 19% and 13% on day 2 and 3 and 12.5% on rewarming.
Sarnat scoring and EEG background had a statistically significant positive correlation (+0.5,p-0.000). Seizures on day 1, 2 ,3 and rewarming also demonstrated a statistically significant positive correlation with respect to each other.

In neonates undergoing TH, if the CEEG shows a normal/mildly abnormal background and no seizures in the first 24 hrs, there is low risk for future seizures.