Impact of post-cardiac arrest seizures on neurological prognosis

The occurrence of epileptic seizures (ES) in patients who have suffered a cardiac arrest (CA) is considered a marker of poor neurological prognosis. Neurological injuries following CA are critical in determining both prognosis and the potential for functional recovery in these patients. Our objective was to investigate the differences between patients who developed ES after CA and those who did not, as well as to explore differences according to the time of ES onset in relation to the return of spontaneous circulation (ROSC). This was a single-center retrospective study including all patients admitted to a Coronary Care Unit with recovered CA between January 2021 and February 2024. Clinical, demographic, laboratory, and imaging variables obtained during hospitalization were collected. A total of 105 patients were admitted for CA, 65.7% of which were out-of-hospital, 89.5% witnessed, with a mean age of 65 years; 30.5% of the cohort were women. 23 patients (22%) experienced ES during hospitalization, of whom 14 (61%) presented ES within the first 48 hours after ROSC. No statistically significant differences were observed in baseline characteristics between patients who developed ES and those who did not. Likewise, no significant differences were found regarding CA etiology, laboratory parameters, No Flow time, or time to ROSC. However, statistically significant differences were observed in patients with ES, who had longer Low Flow times and lower scores on the Glasgow Coma Scale (GCS). Statistically significant differences were also found in the Cerebral Performance Category (CPC), with higher scores at discharge, a higher frequency of EEG findings consistent with severe brain injury, and evidence of extensive hypoxic-ischemic damage on imaging studies in patients who developed ES. No significant differences were observed in neurological outcome variables when analyzed according to the timing of ES onset. In summary, patients who developed ES after CA presented with longer Low Flow times and lower GCS scores. Furthermore, ES were associated with worse neurological outcomes, as reflected by higher CPC scores at discharge and patterns of hypoxic-ischemic injury both on EEG and imaging studies. No significant differences were found in neurological prognosis with respect to the timing of ES onset.