P.096 Optimizing the Use of Continuous EEG Monitoring in Neonatal Encephalopathy

Background: Newborns with hypoxic-ischemic encephalopathy (HIE) are at high risk for seizures, the majority of which have no clinical signs and therefore require continuous electroencephalographic (cEEG) monitoring for their detection. We sought to determine which neonates are at highest risk for seizures in order to optimize allocation of scarce cEEG resources. Methods: We identified term neonates diagnosed with HIE who underwent at least 24 hours of protocol-based cEEG monitoring between 2016 and 2019. We quantified seizure incidence, timing and burden, and correlated these with potential risk factors such as HIE severity, use of therapeutic hypothermia, preceding suspected clinical seizures, amplitude-integrated EEG (aEEG) background and patterns suspicious for seizures, and use of anti-seizure drugs. Results: cEEG monitoring was completed in 218 neonates with HIE, of whom 164 (75%) underwent therapeutic hypothermia. Preceding clinical/aEEG seizures occurred in 147 (67%), 99 (67%) of whom had been cooled but only 22 (10%) had cEEG-confirmed seizures. Characterization of seizure burden and correlation with potential risk factors is ongoing. Conclusions: Although seizures are commonly suspected in neonates with HIE, they are infrequently confirmed during cEEG monitoring, creating opportunities for more efficient risk-based allocation of cEEG resources.

Seizure Control in Neonates Undergoing Screening vs Confirmatory EEG Monitoring

Objective:To determine whether screening continuous EEG monitoring (cEEG) is associated with greater odds of treatment success for neonatal seizures.Methods:We included term neonates with acute symptomatic seizures enrolled in the Neonatal Seizure Registry (NSR), a prospective, multicenter cohort of neonates with seizures. We compared two cEEG approaches: (1) Screening cEEG, initiated for indications of encephalopathy or paralysis without suspected clinical seizures, and (2) Confirmatory cEEG, initiated for the indication of clinical events suspicious for seizures, either alone or in addition to other indications. The primary outcome was successful response to initial seizure treatment, defined as seizures resolved without recurrence within 30 minutes after initial loading dose of anti-seizure medicine. Multivariable logistic regression analyses assessed the association between cEEG approach and successful seizure treatment.Results:Among 514 neonates included, 161 (31%) had screening cEEG and 353 (69%) had confirmatory cEEG. Neonates with screening cEEG had a higher proportion of successful initial seizure treatment than neonates with confirmatory cEEG (39% versus 18%; p<0.0001). After adjusting for covariates, there remained a greater odds ratio (OR) for successful initial seizure treatment in the screening vs. confirmatory cEEG groups (adjusted OR 2.44, 95% CI: 1.45-4.11, p=0.0008).Conclusions:These findings provide evidence from a large, contemporary cohort of neonates that a screening cEEG approach may improve odds of successful treatment of acute seizures.Classification of Evidence:This study provides Class III evidence that for neonates a screening CEEG approach, compared to a confirmatory EEG approach, increases the probability of successful treatment of acute seizures

High Incidence of Epileptiform Potentials During Continuous EEG Monitoring in Critically Ill COVID-19 Patients

Objective: To analyze continuous 1- or 2-channel electroencephalograms (EEGs) of mechanically ventilated patients with coronavirus disease 2019 (COVID-19) with regard to occurrence of epileptiform potentials.Design: Single-center retrospective analysis.Setting: Intensive care unit of Hannover Medical School, Hannover, Germany.Patients: Critically ill COVID-19 patients who underwent continuous routine EEG monitoring (EEG monitor: Narcotrend-Compact M) during sedation.Measurements and Main Results: Data from 15 COVID-19 patients (11 men, four women; age: 19–75 years) were evaluated. Epileptiform potentials occurred in 10 of 15 patients (66.7%).Conclusions: The results of the evaluation regarding the occurrence of epileptiform potentials show that there is an unusually high percentage of cerebral involvement in patients with severe COVID-19. EEG monitoring can be used in COVID-19 patients to detect epileptiform potentials.

Triphasic waves on electroencephalogram in patients with encephalopathy and their diagnosis significance. A review

Triphasic waves are high-amplitude (>70 µV) positive sharp transients preceded and followed by relatively low-amplitude negative waves. The distribution is generalized and tends to have a repetition rate of approximately 1 to 2 Hz. This EEG-pattern is traditionally associated with hepatic encephalopathy, although they have been observed in a wide array of neurological disorders including subcortical white-matter disease, infections, metabolic disturbances and nonconvulsive status epilepticus.American Clinical Neurophysiology Society suggested Standardized Critical Care EEG Terminology (2012). One of the goals was to eliminate terms with clinical connotations, such as ‘triphasic waves’, a term that implies a metabolic encephalopathy with no relationship to seizures for many clinicians. The term ‘triphasic waves’ was replaced by ‘Generalized periodic discharges (GPDs) with triphasic morphology’. The clinical significance ofthese waveforms and their relationship with seizures and prognosis has been debated, and differentiation between interictal patterns, patternsassociated with seizures, and the patterns representing nonconvulsive status epilepticus have been concluded to be a challenge. In cases of uncertainty, the decision to treat should follow on a thorough evaluation with a continuous EEG monitoring and using a short-acting benzodiazepine or non-sedating antiepileptic drugs in order to discern the effects of the pattern on the patient’s clinical exam and EEG.

Perioperative abnormal electroencephalography in a later-stage elderly with septic shock: a case report

Background Patients with sepsis often exhibit abnormal patterns of electroencephalogram (EEG). We report an abnormal EEG pattern in a later-stage elderly patient with septic shock and EEG analysis results. Case presentation An 88-year-old woman with bowel perforation underwent emergency Hartmann surgery. On admission to the operating room, she exhibited septic shock. Her bispectral index value was 30 before anesthesia induction, and the EEG displayed slow waves without burst and suppression throughout the surgery. The relative slow-wave ratio [spectral power (0.5–8 Hz)/(0.5–30 Hz)] from anesthetic induction to the end of surgery was 95.1%, whereas the relative alpha frequency [spectral power (8–13 Hz)/(0.5–30 Hz)] was only 2.4%. Although without preoperative neurological abnormalities, she developed postoperative delirium after admission to the intensive care unit. Conclusions Intraoperative continuous EEG monitoring in elderly patients with sepsis may be useful to predict sepsis-associated encephalopathy. Therefore, continuous EEG monitoring may improve neurological outcomes.

Antiepileptic Drug Management in Acute Ischemic Stroke: Are Vascular Neurologists Utilizing Electroencephalograms? An Observational Cohort Study

Introduction. This study examines the utility of electroencephalography (EEG) in clinical decision making in acute ischemic stroke (AIS) patients in regards to the prescription of antiseizure medications. Methods. Patients were grouped as having positive EEG (+) for epileptiform activity or negative EEG (-). These studies were no more than 30 minutes in length. Patients’ charts were retrospectively reviewed for antiepileptic drug (AED) use before, during, and on discharge from AIS hospitalization. Results. Of the 509 patients meeting inclusion criteria, 24 (4.7%) had a positive EEG. Patients did not significantly differ with respect to any demographic or baseline characteristics with the exception of prior history of seizure. In the EEG- group, AEDs were discontinued in only 3.5% of patients. In the EEG+ group, only 37.5% of patients had an initiation or change to their AED regimen within 36 hours of the study. 62.5% of the EEG+ group had a cortical stroke. Significance. Our results indicate that vascular neurologists are not using spot EEGs to routinely guide inpatient AED management. EEGs may have greater utility in those with a prior history of seizures and cortical strokes. Longer or continuous EEG monitoring may have better utility in the AIS population if there is clinical suspicion of seizure.

Continuous EEG monitoring by a new simplified wireless headset in intensive care unit

Background In critically ill patients continuous EEG (cEEG) is recommended in several conditions. Recently, a new wireless EEG headset (CerebAir®,Nihon-Kohden) is available. It has 8 electrodes, and its positioning seems to be easier than conventional systems. Aim of this study was to evaluate the feasibility of this device for cEEG monitoring, if positioned by ICU physician. Methods Neurological patients were divided in two groups according with the admission to Neuro-ICU (Study-group:20 patients) or General-ICU (Control-group:20 patients). In Study group, cEEG was recorded by CerebAir® assembled by an ICU physician, while in Control group a simplified 8-electrodes-EEG recording positioned by an EEG technician was performed. Results Time for electrodes applying was shorter in Study-group than in Control-group: 6.2 ± 1.1′ vs 10.4 ± 2.3′; p < 0.0001. Thirty five interventions were necessary to correct artifacts in Study-group and 11 in Control-group. EEG abnormalities with or without epileptic meaning were respectively 7(35%) and 7(35%) in Study-group, and 5(25%) and 9(45%) in Control-group;p > 0.05. In Study-group, cEEG was interrupted for risk of skin lesions in 4 cases after 52 ± 4 h. cEEG was obtained without EEG technician in all cases in Study-group; quality of EEG was similar. Conclusions Although several limitations should be considered, this simplified EEG system could be feasible even if EEG technician was not present. It was faster to position if compared with standard techniques, and can be used for continuous EEG monitoring. It could be very useful as part of diagnostic process in an emergency setting.