Abstracts

Rationale: Periodic lateralized discharges (PLDs) are defined as epileptiform discharges occurring at a regular interval and have been reported in critically ill patients. The clinical significance of this EEG pattern has not been well studied in children with acute illness. This report is aimed to identify the clinical features and outcome of children presenting with PLDMethods: This retrospective study was performed at Children’s Hospital at Columbia University Medical Center (2008-2014). Continuous EEG (cEEG) reports for children who were admitted with the acute illness were reviewed to identify PLDs. Chart review was performed to identify clinical and EEG findings during the hospital admission and at the time of hospital discharge.Results: A total of 38 children were identified with PLDs at the time of critical illness. Mean age was 5±5.6 year (2 day to 17 year). Underlying chronic disease was chronic neurological disorder in 20 (52.6%), malignancy in 9 (23.7%), cardiac problems in 4 (10.5%), other metabolic problems in 3 (7.9%). The reason for the admission was seizure/status epilepticus (SE) (n: 19, 50%), presumed CNS infection (n: 5, 13.2%), respiratory depression (n: 4), cardiac arrest (n: 2), surgery (n: 1), altered mental status (n: 1), trauma (n: 1) and evaluation for the underlying condition (n: 5). New imaging abnormalities during admission were reported in 24 (63.2%) patients of which intracranial bleeding or ischemic changes was seen in 12. Indication for EEG recording was seizures (n: 17, 44.7%), SE (n: 10, 26.3%) or mental status change (n: 7, 18.4%). cEEG demonstrated PLDs within the first 2 days in 29 (76.3%) and 22 (57.9%) on the first day. PLDs were longer than 2 days in 18 (47%) and longer than 5 day in 9 (24%). Majority of the seizure (n: 31, 81.6%) were captured within the first 2 days of the monitoring. Most of the seizures captured on EEG was non-convulsive (NCS) (n: 27, 71.1%). Last EEG recording demonstrated resolution of seizures in 30 (78.9%) patients and resolution of PLDs in 31 (81.6%) patients. At the time of discharge, 22 patients had no new neurological symptom or had mild disability. Moderate to severe disability was noted in 9 patients and 7 patients died. Complications were reported in 30 (78.9%) patients. Longer PLD duration was correlated with younger age (r:-0.5, p: 0.05) and presence of seizures on EEG (r: 0.6, p: 0.01). Clinical outcome was not correlated with the duration of PLD, ICU stay, new imaging findings, seizure resolution or NCS on EEG.Conclusions: Periodic lateralized discharges are seen in critically ill children often during the early phase of acute illness. In this study, the majority (76%) was seen in the initial 48 hours of monitoring and 24% was seen in the later course of the critical illness. This EEG pattern is associated with non-convulsive seizures in children and younger age group appears to be more vulnerable for longer duration of PLDs. The underlying etiology, new imaging findings, length of hospital stay, NCS do not affect the clinical outcome in children presenting with PLDs.