Last week, I covered a disastrous prevalence study that almost certainly over-estimates the frequency of pulmonary embolism in syncope. Today, something similar – the frequency of epilepsy in patients presenting to the Emergency Department with first-time seizure.
The most recent American College of Emergency Physicians position statement regarding first-time seizures is fairly clear: first-time seizures need not be started on anti-epileptic therapy. The thinking goes, of course, that few patients would be ultimately diagnosed with epilepsy, and most of those initiated on anti-epileptics would be exposed only to their adverse effects without any potential for benefit.
This small study tries to better clarify the frequency of an epilepsy diagnosis. At a single center, during convenience business hours Monday through Friday, consecutive patients with first-time seizure of uncertain etiology were screened for enrollment. During their enrollment period, they were able to capture 71 patients for whom they were able to complete an EEG in the Emergency Department. Of these, 15 (21%) patients were diagnosed with epilepsy based on their ED EEG. All of these patients were then initiated on an anti-epileptic, most commonly levetiracetam. Anti-epileptic therapy was additionally started on two patients with abnormal EEGs and structural brain disease on imaging, one of whom was able to be contacted in follow-up with a repeat EEG showing epilepsy. These authors use these data to suggest potential benefit for EEG performed in the ED.
This is a fairly reasonable conclusion, although the level of evidence from this single study is weak. This is probably another example of the ED filling a gap in outpatient follow-up; it would almost certainly be perfectly safe to discharge these patients without investigation or initiation of therapy if an ambulatory EEG could be arranged within a few days. Further, larger-scale evaluation of the value of an ED EEG would be needed to modify our current approach.
“The First-Time Seizure Emergency Department Electroencephalogram Study.”