When should a seizure be terminated?

From the Guidelines

A seizure should be terminated if it lasts longer than 5 minutes or if the person experiences multiple seizures without returning to baseline consciousness between them (status epilepticus), as recommended by the 2024 American Heart Association and American Red Cross guidelines for first aid 1.

Key Considerations

• The definition of status epilepticus is a seizure lasting longer than 5 minutes or multiple seizures without a return to baseline consciousness between them.
• First-line treatment typically involves benzodiazepines such as lorazepam, diazepam, or midazolam.
• If seizures persist after two doses of benzodiazepines, second-line medications like fosphenytoin, valproate, or levetiracetam should be administered.

Evidence-Based Recommendations

• The 2024 American College of Emergency Physicians (ACEP) clinical policy recommends that emergency medical services should be activated for seizures lasting more than 5 minutes, multiple seizures without return to normal, or seizures with injuries, breathing difficulty, or choking 1.
• A Class I study by Kapur et al. found that levetiracetam, fosphenytoin, and valproate were effective in terminating seizures in roughly half of all patients receiving one of the three medications 1.

Important Considerations for Patient Care

• Prolonged seizures can cause neuronal damage due to excitotoxicity from excessive glutamate release, leading to calcium influx and cell death.
• Seizures lasting more than 30 minutes are associated with higher mortality rates and poorer neurological outcomes.
• Caregivers of patients with known epilepsy should be educated about rescue medications like rectal diazepam or nasal midazolam that can be administered at home before emergency services arrive.

Key Takeaways

• Status epilepticus is a medical emergency that requires prompt treatment.
• Benzodiazepines are the first-line treatment for status epilepticus.
• Second-line medications like fosphenytoin, valproate, or levetiracetam should be administered if seizures persist after two doses of benzodiazepines.

From the FDA Drug Label

If seizures cease, no additional lorazepam injection is required. The seizure should be terminated when it ceases, as indicated by the cessation of seizure activity.

• Key consideration: The decision to terminate a seizure is based on the cessation of seizure activity.
• Main idea: Seizure termination is indicated when the seizure activity stops. 2

From the Research

Seizure Termination

When a seizure should be terminated is a critical question in the management of epilepsy. According to the available evidence:

• A seizure that lasts more than 5 min probably needs to be treated as status epilepticus 3
• Status epilepticus is defined as a continuous seizure lasting more than 30 min, or two or more seizures without full recovery of consciousness between any of them 3
• The duration of different types of seizures, such as myoclonic, epileptic spasms, tonic, atonic, generalized clonic, typical absence, atypical absences, focal aware, impaired awareness, generalized tonic-clonic, and focal-to-bilateral tonic-clonic seizures, have been studied and the results show that all focal seizures terminated within 10 min and all tonic-clonic seizures terminated within 5 min 4

Treatment of Status Epilepticus

The treatment of status epilepticus involves the use of anticonvulsants, such as benzodiazepines, phenobarbital, and phenytoin. However, these medications have several adverse effects. Alternative treatments, such as intravenous sodium valproate, have been shown to be effective and safe in controlling convulsive status epilepticus and acute prolonged convulsive seizures in children 5 and adults 6.

• Intravenous valproate was successful in seizure termination in 90% of patients compared to phenobarbital in 77% of patients 5
• Intravenous valproate is as effective as intravenous phenytoin in treating benzodiazepine refractory status epilepticus 6
• Phenobarbital, high-dose levetiracetam, and high-dose valproate are probably equally effective in seizure cessation within 60 min of administration in patients with benzodiazepine-resistant status epilepticus 7

Key Findings

Key findings from the studies include:

• The importance of early treatment of status epilepticus to avoid a refractory state 3
• The need for aggressive management with second-line medications, such as barbiturates, propofol, or other agents, in patients with persistent seizures refractory to first-line medications 3
• The effectiveness and safety of intravenous sodium valproate in controlling convulsive status epilepticus and acute prolonged convulsive seizures in children 5 and adults 6