Prolonged Monitoring of Brain Electrical Activity in the Intensive Care Unit
Thiago Carneiro, Shweta Goswami, Christine Nicole Smith, Maria Bruzzone Giraldez, Carolina B. Maciel
Neurologic Clinics,
Volume 43, Issue 1,
2025,
Pages 31-50,
ISSN 0733-8619,
ISBN 9780443130731,
https://doi.org/10.1016/j.ncl.2024.08.001.
(https://www.sciencedirect.com/science/article/pii/S0733861924000604)
Abstract
Electroencephalography (EEG) has been used to assess brain electrical activity for over a century. More recently, technological advancements allowed EEG to be a widely available and powerful tool in the intensive care unit (ICU), where patients at risk for cerebral dysfunction and brain injury can be monitored in a continuous, real-time manner. In the last 2 decades, several organizations established guidelines for continuous EEG monitoring in the ICU, defining critical care EEG terminology and technical standards for technicians, machines, and electroencephalographers. This article provides an overview of the current role of continuous EEG monitoring in the ICU.
Clinical Correlates of Cyclic Alternating Pattern of Encephalopathy
Crystal Yu, Christine Smith, T. Maxwell Parker, Karly Landvay, Calvin Hu, Stephan Eisenschenk, Yue Wang, Maria Bruzzone, Carolina Maciel
May 3, 2022
98 (18_supplement) 997
https://doi.org/10.1212/WNL.98.18_supplement.997
Abstract
Objective: To describe the clinical characteristics of a cohort of patients that developed Cyclic Alternating Pattern of Encephalopathy (CAPE) during long term encephalographic monitoring (LTM).
Background: The 2021 updated ACNS Standardized Critical Care EEG Terminology introduced CAPE as a new term, defined by changes in background patterns each lasting at least 10 seconds and spontaneously alternating in a regular manner for at least 6 cycles. The clinical significance of CAPE is currently unknown.
Design/Methods: This is a retrospective study on adult patients admitted to UF Health Gainesville from 10/1/2020–10/31/2020 that underwent LTM for evaluation of encephalopathy for 12 or more hours. If cyclic pattern was present on q-EEG analysis, one of two groups of two board-certified encephalographers independently reviewed the raw EEG to confirm CAPE. Chart review was performed to evaluate for patient clinical characteristics of interest.
Results: During October 2020, 69 patients were admitted and underwent LTM monitoring for evaluation of encephalopathy at some point during their admission. Seventeen (25%) patients developed CAPE. Patient age ranged from 25–81 years (median 67 years). In terms of race, 5 patients were black, 1 was Asian, and 11 were white. Four patients were female and thirteen were male. Only 2 patients lacked primary CNS insult as reason for admission. Pre-existing neurologic comorbidities included seizures, stroke, dementia, sleep disorders, and history of VP shunt. Fifteen out of seventeen patients were in the ICU when CAPE was identified. In terms of outcomes, 3 patients died in the hospital, 3 were transferred to hospice, 3 were discharged to long term care facilities, and 8 were discharged home/short-term rehabilitation units.
Conclusions: CAPE is not an uncommon EEG finding in patients with encephalopathy; however, little information exists on its etiology or clinical significance. A better understanding of the clinical factors associated with CAPE is needed to further investigate its implications and prognosis.
Pregabalin for Recurrent Seizures in Critical Illness: A Promising Adjunctive Therapy, Especially for cyclic Seizures.
Busl, K.M., Fong, M.W.K., Newcomer, Z. et al.
Neurocritical Care 37, 140–148 (2022).
https://doi.org/10.1007/s12028-022-01459-6
Abstract
Background: Pregabalin (PGB) is an effective adjunctive treatment for focal epilepsy and acts by binding to the alpha2-delta subunit of voltage-gated calcium channels to reduce excitatory neurotransmitter release. Limited data exist on its use in the neurocritical care setting, including cyclic seizures—a pattern of recurrent seizures occurring at nearly regular intervals. Although the mechanism underpinning cyclic seizures remains elusive, spreading excitation linked to spreading depolarizations may play a role in seizure recurrence and periodicity. PGB has been shown to increase spreading depolarization threshold; hence, we hypothesized that the magnitude of antiseizure effect from PGB is more pronounced in patients with cyclic versus noncyclic seizures in a critically ill cohort with recurrent seizures.
Methods: We conducted a retrospective case series of adults admitted to two academic neurointensive care units between January 2017 and March 2019 who received PGB for treatment of seizures. Data collected included demographics, etiology of brain injury, antiseizure medications, and outcome. Continuous electroencephalogram recordings 48 hours before and after PGB administration were reviewed by electroencephalographers blinded to the administration of antiseizure medications to obtain granular data on electrographic seizure burden. Cyclic seizures were determined quantitatively (i.e., < 50% variation of interseizure intervals for at least 50% of consecutive seizures). Coprimary outcomes were decrease in hourly seizure burden in minutes and decrease in seizure frequency in the 48 hours after PGB initiation. We used nonparametric tests for comparison of seizure frequency and burden and segmented linear regression to assess PGB effect.
Results: We included 16 patients; the median age was 69 years, 11 (68.7%) were women, three (18.8%) had undergone a neurosurgical procedure, and five (31%) had underlying epilepsy. All seizures had focal onset; ten patients (62.5%) had cyclic seizures. The median hourly seizure burden over the 48 hours prior to PGB initiation was 1.87 min/hour (interquartile range 1.49–8.53), and the median seizure frequency was 1.96 seizures/hour (interquartile range 1.06–3.41). In the 48 hours following PGB (median daily dose 300 mg, range 75–300 mg), the median number of seizures per hour was reduced by 0.80 seizures/hour (95% confidence interval 0.19–1.40), whereas the median hourly seizure burden decreased by 1.71 min/hour (95% confidence interval 0.38–3.04). When we compared patients with cyclic versus noncyclic seizures, there was a relative decrease in hourly seizure frequency (− 86.7% versus − 2%, p = 0.04) and hourly seizure burden (− 89% versus − 7.8%, p = 0.03) at 48 hours.
Conclusions: PGB was associated with a relative reduction in seizure burden in neurocritically ill patients with recurrent seizures, especially those with cyclic seizures, and may be considered in the therapeutic arsenal for refractory seizures. Whether this effect is mediated via modulation of spreading depolarization requires further study.
Oral Pregabalin As Adjunctive Treatment For Symptomatic Cyclic Seizures In Neurocritically Ill Patients
Mitesh Patel, Zachary Newcomer, Scott Cohen, Rakesh Harshvadan Jadav, Michael Fong, Sotiris Mitropanopoulos, Maria Bruzzone, Katharina Busl, Carolina Maciel
April 13, 2021
96 (15_supplement) 4740
https://doi.org/10.1212/WNL.96.15_supplement.4740
Abstract
Objective: To share our multi-center experience with Pregabalin (PGB) in neurocritically ill patients with refractory seizures.
Background: PGB is an approved adjunctive treatment for focal epilepsy in adults. PGB lacks drug-drug interactions, has a favorable safety profile, and can be rapidly titrated. However, data remains limited regarding its use in the ICU setting.
Design/Methods: Charts of 9 patients admitted to University of Florida Health Neuro ICU from 1/2018–3/2019 and 7 patients admitted to Yale University Health Neuro ICU from 1/2017 – 3/2019 who were monitored on continuous electroencephalography (EEG) and received PGB for the management of refractory seizures were retrospectively reviewed. EEGs were independently reviewed by a board-certified epileptologist or ICU-electroencephalographer. Demographics, anti-seizure drug (ASD) regimen, EEG data pre and post PGB administration were analyzed. Average and median seizure burden (cumulative duration of seizures in minutes per hour) were analyzed.
Results: When comparing median seizure frequency 48 hours pre to 48 hours post PGB administration, there was a decrease of 1.52 seizures per hour (p=0.015). There was also a significant decrease of 1.79 in median seizure burden (p=0.039). Using segmented linear regression analysis, we are able to further characterize the impact of PGB by analyzing immediate change in seizure burden and change per hour after PGB administration. There was an immediate decrease in the median seizure burden by 1.71 (p=0.014) and a decrease in median seizure burden per hour after PGB administration by 0.06 (p=0.028).
Conclusions: In this series of neurocritically ill patients with symptomatic cyclic seizures and various underlying neurocritical conditions, addition of PGB lead to a significant reduction of seizure burden. PGB may represents a good compliment to other ASDs in this population given its pharmacokinetic profile, bioavailability, and limited drug-drug interactions. Future studies should include prospective PGB treatment protocols.
Pregabalin As Adjunctive Treatment For Symptomatic Cyclic Seizures In Neurocritically Ill Patients
Zachary Newcomer, Mitesh Patel, Katharina Busl, Jiang Meilin, Li Zhigang, Katherine Thomspson, Marc Alain Babi, Christopher Robinson, Maria Bruzzone, Maria Hella, Stephan Eisenschenk, Carolina Maciel
April 14, 2020
94 (15_supplement) 4835
https://doi.org/10.1212/WNL.94.15_supplement.4835
Abstract
Objective: To share our experience with Pregabalin (PGB) in neurocritically ill patients with refractory seizures
Background: PGB is an approved adjunctive treatment for focal epilepsy in adults. PGB lacks drug-drug interactions, has a favorable safety profile and can be rapidly titrated. However, data remains limited regarding its use in the ICU setting.
Design/Methods: Charts of eight patients admitted to UF Health Shands Neuroscience Intensive Care Unit from 1/2018 – 3/2019 monitored on continuous electroencephalography (EEG) who received PGB for the management of refractory seizure were reviewed retrospectively. Demographics, antiseizure drug (ASD) regimen, 24 hour EEG data pre and post PGB were analyzed descriptively.
Results: The cohort comprised of eight patients (4 females) of which three patients had epilepsy, two with intracerebral hemorrhage (ICH), two with tumors, and one with cardiac arrest as underlying etiology of refractory seizures. All patients had other ASDs administered prior to PGB. Six of these patients received loading doses of ASDs prior to PGB. Loaded ASDs included Phenytoin (PHT), Levetiracetam (LEV), and Lacosamide (LCM). PGB was dosed 300–400mg/day in 2–4 divided doses, following a load of 75–300mg. PGB led to seizure cessation in 3 patients within 24h and in 2 additional patients within 48h of administration. PGB was successful in significantly (p<0.01 by paired Wilcoxon test) reducing average seizure burden 24 pre and post PGB administration from 8.08 minutes/hr to 3.10 minutes/hr.
Conclusions: In this critically ill cohort with refractory seizures, PGB successfully aborted seizures in 75% of patients. Average seizure burden was significantly lower after addition of PGB. PGB may represent a good alternative to other ASD in this population. Future studies should include prospective PGB treatment protocols.