The patient in status epilepticus presents an immediate resuscitative challenge to the emergency clinician, as efforts to terminate seizures must be carried out simultaneously with measures to support the airway, breathing, and circulation as well as diagnostic maneuvers directed at identifying dangerous underlying disorders. Emergency providers should not be distracted by definitions of status epilepticus that vary across sources and treat as status epilepticus any patient who arrives seizing or any patient who has a seizure in the ED that does not self-terminate or respond to initial therapies. When confronted with a patient in status epilepticus who does not respond to benzodiazepine treatment, the clinician should consider underlying causes that require specific therapies such as hypoglycemia, hyponatremia, eclampsia, and toxic exposures amenable to antidotes (eg, isoniazid, heterocyclic antidepressants, cyanide, carbon monoxide). Most patients with refractory status should be intubated and started on a barbiturate or propofol infusion with or without high-dose phenytoin and/or intravenous valproate. Hypotension should be anticipated and managed in these cases.
If the seizure has terminated and ABCs are stable, the emergency clinician must determine whether the patient had a seizure or another episodic disorder such as syncope or complex migraine. If a presumptive diagnosis of seizure is made in a patient not known for seizures, management is directed at finding dangerous and reversible causes. A non-contrast brain CT is indicated in most patients with first seizure to rule out structural causes. In younger patients where radiation concerns are more prominent, MRI is an alternative. Although laboratory studies are of low yield in patients whose symptoms have resolved, serum chemistry analysis in the ED is prudent. Lumbar puncture should be performed on immunocompromised patients and patients for whom central nervous system infection is a significant concern. Although toxicologic causes of seizures can be life-threatening, undirected toxicology testing such as a urine drug screen is unlikely to alter ED management. It is worth special mentioning that alcohol-related or alcohol-withdrawal seizure is a diagnosis of exclusion; alcoholics are at particular risk for several other dangerous causes of seizures.
Another AAN practice parameter published in the same issue as the guideline abstracted here looked specifically at the utility of brain CT in the ED in various populations of patients who present with seizure.6 Their conclusions are similar to the recommendations made in the abstracted report on evaluating the first seizure; in addition, the panel makes a class II recommendation that patients who present with chronic seizures are more likely to have an abnormal brain CT if there is an abnormal neurologic examination, a predisposing history of neurologic disease, or a focal seizure onset.
The EEG provides important information regarding prognosis and seizure classification; however, it is not required in the ED when dangerous etiologies of seizure have been ruled out and the patient has returned to clinical baseline. The chief indications for performing an emergent EEG are to assess the patient paralyzed and intubated for status epilepticus, and to rule out nonconvulsive status epilepticus in the patient with altered mentation, especially in patients who do not return to baseline after a generalized seizure. The emergency clinician is not compelled to initiate anticonvulsant therapy in uncomplicated cases; however, this decision is ideally made in collaboration with the neurologist who will see the patient in follow-up.
Though fosphenytoin can be infused more quickly than phenytoin, it does not work faster or cause fewer adverse effects than phenytoin and should not be routinely used in place of its much less expensive parent.7,8 Fosphenytoin is preferred in cases where the patient cannot complain of pain if extravasation occurs (eg, a comatose patient) or when intramuscular delivery is required. In patients who will not be quickly discharged from the department, oral phenytoin loading is underutilized; in uncomplicated patients at low risk for immediate recurrent seizure, oral loading is effective and offers benefits of convenience, cost, and safety.8,9