Abstracts

Rationale: A reported seizure frequency after cardiac arrest is 3-44%. Sedation and paralytics mask most seizure activity during the cooling phase. The study is evaluating the use of cEEG during cooling protocol post cardiopulmonary arrest and the effect of seizure treatment on outcome.Methods: A retrospective case series looking back at 41 adult cardiopulmonary arrest patients, who underwent cooling protocol with continuous EEG monitoring. Inclusion criteria are: adult patients (18years and older), with a downtime range of five to thirty minutes, no past medical history of seizures, and time of EEG initiation within 4 hours of asystole. Downtime is defined as the total time of cardiopulmonary arrest (asystole). Cooling protocol is defined as the use of a cooling blanket to achieve rapid temperature between 33-34 C for the first 12 hrs (induction phase and maintenance phase) and then a 12 hr rewarming phase at a rate of .2-.5 per hr until homeostatic temperature is achieved.Results: Of the 41 patients analyzed, diffuse slowing was observed in 34% (14/41), isolated isoelectric activity in 22% (9/41), seizure activity was found in 17% (7/41), isolated burst suppression (BS) in 7% (3/41), BS + isoelectric activity in 7% (3/41), BS + epileptiform discharge (ED) in 5% (2/41), BS + diffuse slowing 5% (2/41), and alpha coma in 2% (1/41). Seizure activity included electrographic seizures with or without clinical manifestations and status epilepticus. In the patients with seizure activity, the study found 43% (3/7) with status epilepticus, and 57% (4/7) with intermittent seizure activity. No relationship between epileptiform discharges and seizure activity existed within any one EEG however majority of seizure activity was preceded by burst suppression. In all patients with seizure activity and epileptiform discharges, the final outcome was death, even after AED use. Overall, outcome showed that 30% (12/41) recovered neurological function in stable condition who were eventually discharged home or to a skilled nursing facility after recovery while 70% (29/41) resulted in death.Conclusions: Continuous EEG is useful in cooling protocol cases because of the high rate of seizures. This is consistent with the current literature on cardiopulmonary arrest. Our hypothesis was that early and aggressive treatment of seizure activity and epileptiform discharges would result in improved outcomes. However, our results did not prove that use of empirical AED treatment results in increased survival rate. Outcome in all seizure patients was found to be death with treatment upon seizure activity presence. Of the 41 patients, 30% recovered with majority showing diffuse slowing on EEG followed by burst suppression and alpha coma.