Abstracts

Rationale: Prognostication for post cardiac arrest patients is a common inpatient consultation encountered by practicing neurologists. Such evaluations can be very challenging and could have serious consequences leading to futile decisions such as withdrawal of care. Clinical assessment remains the cornerstone for prognostication. Neurophysiological data including electroencephalogram (EEG) and somatosensory evoked potential (SSEP) are used to aid in prognostication. The classification of EEG findings and correlation with clinical outcome remain challenging, at times uncertain. In this retrospective study, we analyzed data of patients admitted to a tertiary Center in Qatar post cardiac arrest who underwent Continuous EEG monitoring for at least 24 hours, without withdrawal of care regardless of their prognosis. Methods: We reviewed EEG findings and clinical outcome of patients who had EEG following cardiac arrest between 2014 and 2017. All patients underwent Continuous EEG monitoring for at least 24 hours. No hypothermia protocol was used in these patients. We considered background suppression with and without discharges and burst-suppression as highly malignant EEG patterns, We also considered abundant periodic or rhythmic discharges, malignant discontinuous and low voltage background and unreactive EEG as malignant EEG patterns. Clinical outcome was measured by using the modified Rankin scale (MRS) with MRS of 2 or less considered as a favorable outcome. Results: Twenty-five post cardiac arrest patients underwent continuous EEG monitoring. The age ranged from 47 to 79  years (mean age 71.8). 20 patients (80%) had poor outcome; 12 of them (60%) had malignant EEG patterns, 5 (25%) had highly malignant EEG patterns and only 3 patients (15%) had benign EEGs post cardiac arrest. 60% of patients who had good outcome also had a malignant EEG pattern including one patient with highly malignant burst suppression noted on continuous EEG. Malignant EEG patterns were seen in 56% of patients regardless of clinical outcome while highly malignant patterns were seen in 24% overall. Conclusions: Although highly malignant and malignant EEG patterns are generally associated with poor outcome, our results demonstrate that favorable outcome may still be achieved even in patients with these patterns on continuous EEG monitoring. We suggest utilizing EEG monitoring in the acute phase to help in treatment decision making rather than the confirmation of a poor long-term clinical outcome. Funding: No funding