Seizures - afebrile
Managing the child who presents with an afebrile seizure
Principles and approach
Treat acute seizure (see Status Epilepticus Guideline)
Is this a seizure? Take detailed history and exam to ascertain whether definitely or possibly a seizure. This includes:
Detailed history obtaining the sequence of events - including the presence or absence of focal features and the level of awareness throughout the seizure. Consider arrhythmic cause for generalized seizures especially occurring at night, or during or following exercise
Developmental history/assessment
Previous seizures? Including events that may not have been recognised as seizures (e.g. in sleep).
Family history of evidence of young sudden death, familial epilepsy or arrhythmic disorders.
Detailed physical examination, including BP, neurological, cardiac amd mental status examination
Order initial investigations based on presentation, and to rule out underlying or other conditions. Always consider blood glucose and calcium measurement, and ECG. Consider toxicology/alcohol screen if ingestion possible.
Identify and manage any underlying or provoking condition that may have triggered seizure.
Neuro-imaging is not usually required acutely. Imaging should be considered for focal seizures, when new focal deficits are noted on examination, after a first status epilepticus, or if EEG suggests underlying structural pathology.
Consider diagnosis: e.g. epilepsy syndrome, non-syndrome epilepsy, febrile or other acute symptomatic seizure, or other condition mimicking seizure.
Use working diagnosis to guide further investigations, treatment, and timing of review.
Provide advice and prepared information for family and patient
Refer for follow up
Flowchart for first seizure
Follow-up
Provide information regarding next steps
If emergency medication is needed, buccal midazolam is the medication of choice. Provide advice, prescription, and information sheets as follows:
Buccal midazolam (for intranasal administration use local protocol with an atomiser):
3 - 11 months 2.5mg 1 - 4 years 5mg 5 - 9 years 7.5mg 10 - 18 years 10mg Prescribe plastic ampoules 15mg/3ml
Info sheets
OR
Rectal diazepam can be considered if buccal midazolam not appropriate:
0.3-0.5mg/kg/dose (max dose usually 10mg)
Dose may only be repeated under medical supervision
Delayed respiratory depression may occur after rectal administration
Info sheet: Emergency management of Seizures using rectal diazepam (Stesolid)
Admission criteria
Recurrent seizures in 24 hour period
Not recovering after a seizure
New onset focal deficit
Encephalopathic
Requiring further acute investigation/management
Family/social considerations
Recurrence risk
Epilepsy comprises a wide range of individual conditions.Risk of seizure recurrence after a first or subsequent afebrile seizure depends on the individual patient, the cause and type of their epilepsy. Quoted risk rates vary between published studies with no single agreed rates. Factors that can affect recurrence risk include:
Type of seizure (focal or generalized)
Underlying cause of the seizure (structural, genetic, etc)
Presence of other neurological abnormalities (developmental delay or abnormal examination)
Situation of the seizure (from sleep, due to photic stimulation, etc)
EEG findings (although EEG must be interpreted in light of other factors and clinical presentation)
When discussing recurrence:
Defining the epilepsy type/syndrome gives the most useful guide to seizure recurrence, as well as prognosis, cognition, behaviour and motor outcome. EEG and other investigations can assist with determining epilepsy type.
Seizures associated with underlying neurological or developmental abnormalities have a greater risk of recurrence.
The role of EEG following a first afebrile epileptic seizure is to help determine the seizure syndrome, hence why it should be requested once a paediatrician has determined that the seizure event is epileptic in nature.
Starting anticonvulsant medication
Regular anti-epileptic medication is not usually recommended after a first afebrile seizure. Whether to start medication, and the medication choice is determined by the seizure type or most likely seizure syndrome. This is usually determined by the paediatrician providing ongoing management.
The New Zealand Epilepsy Guidelines gives recommendations for treatment based on epilepsy & seizure types. Dosing advice and patient/carer information sheets are contained in the New Zealand Formulary for Children for the following medications. Adverse affects are also detailed in the NZ Formulary, however some specific issues are highlighted below.
Carbamazepine. Screen children of South East Asian origin for HLA-B*1502 haplotype via the Blood Bank prior to the initiation of carbamazepine - positive children should not receive carbamazepine (increased risk of Stevens Johnson Syndrome)
Sodium valproate. Teratogenetic risk - avoid if possible in young women of child-bearing potential. Advise effective contraception if unavoidable.