Abstracts

Rationale: Following cerebral anoxia, non-convulsive status epilepsy (NCSE) often occurs. Mortality has been reported to be very high and outcomes very poor in the survivors. This study aims to identify factors which may influence the mortality rate and outcomes in these patients.Methods: After IRB approval, we retrospectively reviewed patients with NCSE associated with cerebral anoxia due to cardiac arrest at Ochsner Medical Center between 2012 and 2014. Variables documented were duration of anoxia, delay in diagnosis of NCSE, duration of NCSE, control of NCSE, and findings on MRI/CT scans. The Glasgow-Pittsburgh Cerebral Performance Categories (CPC) Scale was used for outcome assessment.Results: 14 patients, 9 females and 5 males, were identified. Age range was 35-77 (mean 58.2 yrs). Duration of anoxia ranged from 10 to 40 minutes. Delay of NCSE diagnosis from time of cardiac arrest ranged from 0 to 8 days. EEG was non-reactive in 4 pts, all of whom did not survive. MRI findings were categorized as normal (0), only chronic changes (3), acute ischemic changes limited to cortex (3), and ischemic changes involving cortical and sub-cortical areas (7). CT findings of acute ischemic changes were found in only 2 patients. Only one patient with image evidence of ischemic changes survived. Control of NCSE was achieved in 13 (93%) patients, and complete resolution of status without recurrence in absence of anesthetics was achieved in 10 (71%). Two patients were discharged to long term care facilities with CPC scores of 4 and died within one month from multiple organ dysfunctions (MOD). Two patients survived with CPC scores of 1 and 2. In-hospital mortality was exclusively due to withdrawal of care (71%) and documented reasons were MOD (70%) and poor neurological prognosis (30%). Therapeutic hypothermia (TH) protocol was used in 71% of patients and did not predict survival.Conclusions: Control of NCSE can be achieved in most patients with NCSE from anoxic injury. Inability to achieve control was not related to duration of anoxia, treatment delay, duration of NCSE, or degree of ischemic injury on neuroimaging. Control of NCSE was achieved with anesthetics including propofol and ketamine along with anti-epileptic medications. Two patients survived and continued to demonstrate good outcomes. Clinical features common to these patients were shorter delay in diagnosis and management, shorter duration of NCSE, successful control and resolution of NCSE after removal of anesthetics, and no evidence of ischemic injury on MRI/CT. Our findings are encouraging and support efforts to control NCSE in this population. Further studies are recommended to better evaluate favorable outcome predictors for cerebral anoxia. This information would be valuable in prognostication and may influence decisions of goals of care. Duration of anoxia or NCSE did not predict outcome. We therefore recommend against relying on duration of anoxia as a predictor of outcome. Mortality was 100% for patients with a non-reactive EEG or evidence of combined cortical and sub-cortical ischemic injury on MRI.