Abstracts

Rationale: Periodic discharges (PD) and rhythmic activity (RA) are commonly encountered in critically ill adults undergoing continuous EEG monitoring (cEEG), while their prevalence is unclear in children. Our aim was to determine the prevalence of these patterns during cEEG monitoring of critically ill children.Methods: The Pediatric Critical Care EEG Group (PCCEG) consists of eleven hospitals that routinely perform cEEG on critically ill children. Each site retrospectively enrolled 50 consecutive critically ill children (1 month to 21 years) who underwent clinically indicated cEEG. We collected information regarding subject demographics, clinical characteristics, outcome, and the occurrence of specific EEG patterns. Subjects with and without PD and RA were compared using chi-square test for categorical variables and the Mann-Whitney test for continuous variables.Results: 550 patients were included in this study. PD occurred in 76 (13%) and were lateralized in 34 (6%), generalized in 22 (4%), bilaterally independent in 7 (1%), and multifocal in 15 (3%). RA occurred in 54 (10%), including lateralized in 22 (4%), generalized in 20 (4%), bilaterally independent in 67 (1%), and multifocal in 2 (0.5%). PD and RA were seen in children as young as 12 and 15 months respectively. Subjects with PD or RA had more abnormal EEG backgrounds and were more likely to experience seizures or status epilepticus. There was no difference in PICU length of stay with PD or RA. RA was related to mortality.Conclusions: These data provide epidemiologic characterization of PD and RA in critically ill children and establish that these patterns are common, including in young children. cEEG monitoring provides helpful information on clinical features and outcome. PD and RA were associated with a higher risk of seizures or status epilepticus in our series. Further study on how management can be adjusted to impact outcome is warranted.