Abstracts

Rationale: Several studies have suggested a poorer prognosis for cardiac arrest (CA) patients with COVID-19 compared to those without COVID-19. EEG is commonly standard of care after post-cardiac arrest, for both the detection of seizures and prognostication. Our study sought to understand the differences between the clinical and EEG characteristics of comatose post-cardiac arrest patients with and without COVID-19.

Methods: This retrospective study includes two New York Presbyterian Hospitals; Weill Cornell Medical Center, and Queens Hospitals. The data was collected from 3/15/2020 until 06/30/2021 (15.5 months). Inclusion criteria included any patient who had an in or out-of-hospital CA and were monitored with cEEG. A total of 111 patients met the criteria and were included in this study. As per our institutional protocol, all in or out-of-hospital CA patients in coma are considered for targeted temperature management (TTM) if not contraindicated clinically. The patients underwent neurological prognostication tools such as cEEG, SSEP, NSE levels, head CT and brain MRI, if deemed appropriate. The demographics and pertinent clinical variables were collected. EEG data were collected from EEG reports in which 'ACNS standardized critical care EEG terminology' were used. EEG findings such as seizures, status epilepticus, periodic discharges, rhythmic delta activities, burst-suppression pattern (BSP), low voltage (< 20 μV), and EEG reactivity were collected. Outcomes at hospital discharge were measured by the Cerebral Performance Category scale, with 1-2 representing 'good' and 3-5 representing 'poor' outcome. The PCR test for COVID-19 was collected and/or repeated for all patients. Patients were divided into two groups: Cardiac arrest patients with a positive and negative COVID-19 test.

Results: Of those 111 CA patients, 31 (28%) patients were COVID-19 positive, and 80 (72%) patients were COVID-19 negative. Several clinical characteristics were not significantly different between the COVID-19 positive and negative patients, and these were out of hospital arrest (p: 0.11), mean age (p:0.45), female gender (p: 0.86), and initial shockable rhythm (VT or VF) (p: 0.06). Return of spontaneous circulation was significantly different between the two groups (p: 0.035, Mann Whitney U test). Several EEG patterns were not significantly different between the two groups and included LPDs, GRDAs, LRDAs, BSP, low voltage background, and EEG reactivity. The rate of seizures was also not significantly different (p: 0.07). GPDs were seen significantly less in the patients with COVID-19; 6/31 (19%) and 32/80 (40%) (p: 0.04). Status epilepticus was seen significantly less in the patients with COVID-19; the rates were 2/31 (6%) and 18/80 (23%) (p:0.048). There was no significant difference between the rate of good outcome (p: 0.57).

Conclusions: Our data show that CA patients with COVID-19 did not demonstrate more malignant EEG patterns than the CA patients without COVID-19. In contrast, GPDs and status epilepticus were seen less frequently in patients with COVID-19 compared to those without. This suggests that the mechanisms behind worse outcomes may not be related to the brain, but to other organ systems.

Funding: None