Refractory Seizures Dr James Edwards EMCORE May 30th 2014
Refractory Seizures Seizures are a common presentation to the ED and some patients will have multiple seizures or have a reduced level of consciousness (LOC). It is especially important in this group to get collateral history from ambulance/family/friends. Ask for a description of the seizure, was there a focal component, PMHx especially history of seizures or epilepsy, alcohol dependence or malignancy and what medications they are taking. Do you intubate a patient with a reduced level of consciousness (GCS <9) following seizures? Risk of aspiration if not they are not protecting their airway or a delay in aggressively managing their status epilepticus versus the risk of intubation and ventilation. I am more likely to sit and wait rather than intubate for airway protection as most will wake up A new definition of status epilepticus? The classical definition requires 30 mins of seizure activity or without return to normal LOC. But most seizures stop before 5 mins. A new definition; a seizure lasting 5 minutes or more or continuous clinical and/or EEG seizure activity without recovery between seizures. Further classify as convulsive or non -convulsive Seizure Management Stop the seizure Use your favourite benzodiazepine. Lorazepam is recommended 0.1mg/kg up to a dose of 4mg per dose. Midazolam has the advantage of being given IV or IM. Usual dose is 5mg or 0.1mg/kg. Prevent further seizures Phenytoin 1g over 1 hr (20mg /kg but no quicker than 50mg per minute) Sodium valproate and leviceratecam are other first line options Treat the underlying cause Everyone needs a BSL to exclude hypoglycaemia Causes can be divided into acute (metabolic, sepsis, CNS infection, head trauma, drugs toxicity or withdrawal) or chronic (pre-existing epilepsy, ethanol abuse of CNS tumours) Important to consider infection but understand that most patients who have multiple seizures will develop a temperature. For those with a fever and without a history of seizures or a good reason not to consider a CNS infection, they need a CT scan, LP and cover with IV ceftriaxone and acyclovir Manage complications and supportive care Refractory seizures Defined as status epilepticus that does not respond to standard treatment such as an initial benzodiazepine followed by another anti-epileptic drug Which second line anti-epileptic medication? Leviceratecam and sodium valproate are possible agents and choice will usually depend on the preferences of your neurologists and intensivists. However, by this time they are usually intubated and sedated with propofol (or IV midazolam)
When to intubate Intubate with persistent reduced LOC, ongoing seizures, for scanning or transport, to try and reduce some of the metabolic complications and allows you to use IV midazolam or propofol to stop the seizure. Avoid paralysis following intubation if possible as it make it difficult to identify ongoing seizures. If paralysis is required, use EEG monitoring. The EEG should be initiated within one hour of onset of status epilepticus. It is helpful in the ED for patients that remains comatose to differentiate between side effects of medications, ongoing seizures and to rule out non convulsive status epilepticus. It also guides anti-epileptic therapy in the ICU.
A 48 yo male presents with a seizure at home. Further seizure in the ambulance which was terminated after IV midazolam. In ED, drowsy (GCS 8) with no seizure activity.
Patient has a further generalised tonicclonic seizure in the department.
Seizure management
Stop the seizure
Benzodiazepines
Is this Status Epilepticus?
Convulsive status epilepticus? a new definition
Prevent further seizures
Phenytoin
Treat underlying cause
Acute metabolic sepsis CNS infection head trauma drugs- toxicity or withdrawal! Chronic pre-existing epilepsy ethanol abuse CNS tumours
Manage complications and good supportive care
Refractory seizures
Which second line anti-epileptic medication!? leviceratecam (Keppra)? sodium valproate
When to intubate?
Avoid paralysis post intubation if possible unless EEG monitoring available
Role of EEG
Seizure management summary! treat seizure prevent further seizures treat underlying cause manage complications!