Febrile Seizures

Paediatric blue call for a twitching hot tot - you either love them, or hate them. As most of the time the child is pretty much back to normal by the time they arrive in the ED, it's easy to get a bit blaze about Febrile Convulsions or Febrile Seizures.

Febrile seizures: Seizure accompanied by a fever in the absence of inter-cranial infection due to bacterial meningitis or viral encephalitis.

They happen in 3% of children, between 6 months and 3- 5 years of age. The peak incidence is 18 months. Only 6-15% of seizures occur after 4 years. They are normally brief, with a 30-40% risk of a further attack.
10% increased risk if child has first degree relative with febrile seizures
A febrile seizure is more likely the younger the child, the shorter the duration, lower the temp at seizure and family history.  1-2% lifetime risk of epilepsy, same as all kids - complex focal have 4-12% risk

Presentation
- Short duration (<15minutes)
- Single seizure
- Brief post-ictal period
- Fever identified
- Prolonged seizure (5 - 10min) more likely to have a recurrence.

Investigations
Minimal evaluation needed
Urinalysis may be indicated - UTI common cause
Lumbar Puncture - only if child is not well looking, fully immunised, presenting with a simple febrile seizure. It
For complex seizure, consider bacterial meningitis as a cause - it can be difficult to clinically rule it out.

Management
As per departmental policy. Example from Manchester on the CEM website here.
If seizing, follow status epilepticus guidelines.
No evidence on duration of observation, although 24 hours has been suggested.

Advice
Normal seizure advice
Antipyretics do not prevent convulsions but may provide comfort. Diazepam also should not be used as prophylaxis.
 

Seizures in Children

There's lots of information on seizures, and it can be hard to know the differences in management between children and adults. Most of the information says the same thing - just in different ways. There's a podcast from BMJ Learning and information from EMBasic. Nothing really covered generalised seizures in children, so I actually looked at a paper text book to get some information on seizures in children - the "Sunflower Book" as we called it at medical school! 

A seizure is defined as "a clinical event in which there is a sudden disturbance of neurological function caused by an abnormal or excessive neuronal discharge. Seizures may be epileptic or non-epileptic". 

There are lots of differential diagnoses for seizures, and a careful history will help you elucidate the true cause. 
Febrile Seizures - see later
Paroyxysmal Disorders - "funny turns"
Breath holding attacks - child cries, holds his breath, and goes blue. Sometimes children loose consciousness. Behaviour modification + distraction may help.
Reflex anoxic seizures - occur in infants or toddlers. May have a first degree relative with a history of faints. Commonest triggers are pain or discomfort - minor head trauma, cold food (ice-cream or cold drinks), fright or fever. Triggering event, then child becomes pale and falls to floor. May have a generalised tonic-clonic seizure. The episodes are due to cardiac asystole from vagal inhibition. Seizure is brief and the child rapidly recovers. Ocular compression under controlled conditions often leads to asystole and paroxysmal slow-wave discharge on the EEG.
Syncope- faint if in a hot or stuffy environment. Clonic movements may occur.
Migraine- paroysmal headache involving unsteadiness or light-headedness as well as visual or GI disturbance. These symptoms may occur without the headache.
Benign paroxysmal vertigo- recurrent episodes of vertigo, 1- several minutes + nystagmus, unsteadiness or falling.
Cardiac arrhythmia-  prolonged QT = rare
Tics, daydreaming, night terrors
Self-gratification- genital stimulation for comfort, rather than sexual gratification.
Pseudoseizures / fabricated / induced illness: eg adult injecting insulin
Paroxysmal movement disorders - well-circumscribed episodes, genetically determined, no loss of consciousness.

Epilepsy
Incidence 0.05% and prevalence 0.5%
There are lots of different types of epilepsy, depending on which part of the brain is affected. Not all epilepsy is tonic-clonic.
 - Frontal seizures - motor or premotor cortex. May lead to clonic movementsAsymmetrical tonic seizures can be seen, which may be bizarre and hyperkinetic.
- Temporal seizures- strange warming feelings. Lip-smacking, plucking at clothes, automatism.Consciousness can be impaired.
- Occipital seizures -distortion of vision
- Parietal lobe seizures - contralateral dysaesthesias or distorted body image

Epilepsy Syndromes
- West Syndrome - flexor spasms
- Lennox-Gastaut syndrome - drop attacks
- Childhood absence epilepsy

Take a full and careful history. You need to do a full and careful examination - to reassure the parents if nothing else. Most patients can be discharged with outpatient follow up and very careful advice:  cycling in traffic, swimming alone, deep baths, contraception + pregnancy and driving.

Status Epilepticus

The definition of status is, as always controversial. The "traditional" definition is a seizure that lasts 30minutes or more or clusters of seizures lasting for more than 30minutes with no recovery in between.

In 2008, the Neurocritical Care Society introduced a new definition for Status Epilepticus because (to quote boringEM)…
"- By 5 minutes a seizure is like the Energizer Bunny: it keeps going and going… and is unlikely to stop.
 - The brain is frying: 30 minutes (the old definition) was too long because neuronal injury/pharmacoresistance likely occurs WAYYYY before 30 min of continuous seizing."

"Status Epilepticus: Continuous seizure activity for greater than 5 minutes or the occurrence of sequential seizures over a similar period without recovery of consciousness between seizures"

It can be caused by:

 Febrile illness

 Infection (particularly meningoencephalitis)
 Trauma
 Metabolic derangements (including hypoglycaemia & electrolytes, eg. hyponatraemia)
 Medication change
 Drugs
 Idiopathic

Treatment
The NICE Guidelines have a very sensible summary of treatment that is very clear, although it doesn't mention PO/Buccal midazolam. The College of Emergency Medicine has some excellent local charts, including one from Manchester, that has lots of good information on it that is well presented.


Benzodiazepines are always the first, and second choice. We can give benzos by so many routes that we don't need to get stressed about gaining IV access. If we don't manage to gain IV access, paraldehyde is still in the paediatric guidelines. Unlike the adult guidelines, the paediatric guidelines are still very clear that we don't give phenytoin if the patient is already on phenytoin - maybe because we assume children are more likely to be compliant?

Cardiac Arrest in Children - aetiology

There are two types of cardiac arrest in adults, and children.

Primary Cardiorespiratory Arrest: due to an underlying cardiac arrhythmia (eg VF or VT) is more frequent in adults. The onset is often acute and unpredictable. Immediate defibrillation is needed.

Secondary Cardiorespiratory Arrest is more common in children and is because the body can't deal with the underlying injury or illness.
The pre-terminal rhythm in children is often bradycardia which leads to asystole or PEA - non shockable rhythms.

The outcome from cardiorespiratory arrest in children is poor, especially if there is a prolonged duration. Compared to adults, children are physiologically different but like adults, early recognition of the seriously ill child can prevent sudden death.

Some conditions are more likely to affect children than adults, and more likely to cause their arrest:
Croup: remember a narrower tracheal tube than would normally be expected may be required.
Epiglottitis: you must keep the child calm until the airway is secure.
Bronchiolitis
Coma
Seizures
Anaphylaxis: give adrenaline as quickly as possible

Drowning, electrocution and hypothermia can also affect children, and cause cardio-respiratory arrest. In an arrest situation, the standard CPR algorithms should be followed.

Survival rates remain poor, with survival rates of 0 - 38% quoted in the literature.