Although most seizures resolve spontaneously in one to three minutes, the seizures we typically face in the emergency department are the generalized tonic-clonic type and have been going on for a longer period of time, usually fulfilling the Neurocritical Care Society guidelines’ criteria for status epilepticus—a continuous seizure lasting more than five minutes, or two or more seizures within a five-minute period without return to neurological baseline in between.1 We know status epilepticus is associated with a mortality rate as high as 43 percent, and as the duration of seizures increase, the outcomes become poorer, especially in seizures lasting more than 30 minutes, owing to brain anoxia, acidosis, and rhabdomyolysis that occurs with ongoing seizure activity.2,3 In fact, the seizure duration is the only potentially modifiable determinant of mortality. It is believed that the longer the seizure, the more refractory to medication it becomes.4
Explore This IssueACEP Now: Vol 39 – No 07 – July 2020
The point: We should approach seizing patients in the emergency department swiftly and aggressively, with the goal of immediate seizure cessation.
While the patient is placed in the lateral decubitus position with an IV established (with venous blood gas sent off to rule out hyponatremia as a cause of the seizure), capillary glucose checked, and oxygen delivered via nonrebreather and nasal trumpets, the first two doses of medication should be drawn up so they can be given in rapid succession if needed. Benzodiazepines are considered the first-line medication for seizures.1 The most important determinant of benzodiazepine efficacy in terminating seizures may be time to administration rather than choice of benzodiazepine or route.
The goal: to administer the first dose as soon as possible. Although some experts recommend waiting five minutes before administering the first benzodiazepine dose and giving it slowly over a few minutes (the reasoning being that the majority of seizures resolve spontaneously in less than five minutes and that these medications at therapeutic doses produce significant side effects), apnea and hypotension are more common with ongoing seizure activity. Aborting the seizure results in less respiratory depression, despite the high benzodiazepine dose. As such, I recommend administering the first benzodiazepine as soon as possible, via intravenous (IV) push.
The next most important aspect of benzodiazepine administration in patients suffering from status epilepticus concerns adequate dosing. Don’t just give 2 mg of lorazepam. Why? Observational studies suggest benzodiazepines are underdosed in 76 percent of status epilepticus patients.5 It is imperative the first dose of benzodiazepine is dosed properly (ie, lorazepam 0.1 mg/kg IV up to 4 mg or midazolam 0.2 mg/kg intramuscular [IM] up to 10 mg). IV lorazepam is the preferred benzodiazepine because it has been shown to be better than diazepam for time to cessation of seizures and requirement of a different drug or general anesthesia.1,6,7 When no IV is available, IM midazolam is preferred because it has been shown to be noninferior to IV lorazepam in a recent landmark randomized controlled trial.8
Again, treat seizures early via IV push with adequate doses of benzodiazepines.