Seizures, CNS Infections and Encephalopathy

Status Epilepticus: Recognition and Escalation Pathways

Convulsive status epilepticus is a neurological emergency defined as continuous seizure activity lasting at least five minutes, or recurrent seizures where the patient does not regain consciousness between episodes. In contrast, nonconvulsive status epilepticus presents without overt generalized motor convulsions; patients instead demonstrate altered mental status, subtle twitches, or coma. Subtle signs such as sustained gaze deviation, nystagmus, or unexplained fluctuating consciousness necessitate prompt continuous electroencephalography (cEEG) assessment to rule out nonconvulsive seizure activity.

Prolonged convulsive seizures massively increase cerebral metabolic demand, which can elevate intracranial pressure and generate severe systemic lactic acidosis. Beyond the central nervous system, sustained muscle contractions can lead to hyperthermia, metabolic acidosis, rhabdomyolysis, and acute kidney injury. The critical care nurse coordinates multidisciplinary interventions to limit secondary brain injury by monitoring temperature, glucose, and cerebral perfusion and implementing ordered targets when indicated.

The immediate bedside priority in status epilepticus focuses on airway protection, oxygenation, point-of-care glucose testing, and securing intravenous access. First-line pharmacologic treatment requires a prescribed benzodiazepine, such as intravenous lorazepam when IV access is established or intramuscular midazolam when access is absent. If seizures persist despite benzodiazepine administration, second-line treatment involves an intravenous loading dose of an antiseizure medication such as levetiracetam, fosphenytoin, or valproate. Fosphenytoin serves as a prodrug of phenytoin that carries a lower risk of local tissue necrosis and vascular irritation during peripheral infusion, whereas rapid intravenous administration of phenytoin can trigger hypotension and serious cardiac arrhythmias due to its formulation with propylene glycol.

When seizures persist despite adequate doses of a first-line benzodiazepine and a second-line antiepileptic drug, refractory status epilepticus is diagnosed. Management requires continuous intravenous infusions of anesthetics such as propofol, midazolam, or pentobarbital, titrated under provider orders and protocols to an EEG-guided target. These targets include electrographic seizure cessation or burst suppression, an EEG pattern characterized by alternating bursts of electrical activity and periods of markedly suppressed, low-voltage activity. Continuous EEG monitoring must be maintained throughout anesthetic infusions to assess electrographic seizure control and detect recurrence. Under the AACN Synergy Model, the high vulnerability and severe instability of these patients demand advanced nurse competencies in clinical judgment and advocacy.