Abstracts

Rationale: Therapeutic hypothermia (TH) has become a standard procedure for the management of cardiac arrest. An increased incidence of seizures or epileptiform discharges, especially during the rewarming period, has been observed. The actual incidence of epileptiform activity, however, has not been adequately studied. Methods: We retrospectively reviewed the continuous EEG monitoring (c-EEG) findings of 24 patients undergoing TH between June, 2009 and June, 2012. EEG monitoring was started at the onset of TH and continued for at least 24 hours after the rewarming process was started. All the patients were 18 years or older and hemodynamically stable. Patients were maintained at a core body temperature of 32-34° C for twenty-four hours, and received midazolam, fentanyl and vancuronium. Results: Six of the 24 patients (25%) presented some type of epileptiform activity during the c-EEG. Three patients (12.5%) were diagnosed with post-anoxic myoclonic status epilepticus, with overt myoclonic activity and generalized epileptiform discharges on EEG. One patient (4.2%) developed generalized electrographic status epilepticus during the rewarming period. Two patients (8.3%) had interictal epileptiform discharges: one with generalized spike-wave discharges and bursts of diffuse attenuation, the other with transient multifocal epileptiform discharges. Conclusions: In our series the incidence of epileptiform activity, if cases of myoclonic status epilepticus are excluded, was relatively low, but still clinically significant. C-EEG monitoring should be considered an essential component of the therapeutic hypothermia protocol and extend throughout the rewarming process. Further studies are necessary to properly assess the incidence of epileptiform activity in this population.