Febrile seizures: SAQ

This child has had a complex febrile seizure. He is within the defining age window (6 months to 5 years) and had a convulsion with fever and no evidence of a central nervous system infection, which confirms a febrile seizure, but the seizure lasted over 15 minutes and recurred within 24 hours, which makes it complex rather than simple. The otitis media is the fever source. The two defining features that change the management are the prolonged duration, which warranted active termination, and the recurrence, which raises the recurrence and epilepsy risk and shifts the counselling. [1]

Question 1 (10 marks)

Outline your acute management of this child while the second convulsion is ongoing, and justify your investigation plan. [1]

My first priority is to terminate the convulsion, because a febrile convulsion ongoing at five minutes is heading toward status and the longer it lasts the less likely it is to self-terminate. I would secure the airway, give oxygen, confirm the bedside glucose is normal (it is), and obtain intravenous access. Because the convulsion is ongoing, I would give intravenous lorazepam at 0.1 mg per kg, maximum 4 mg, repeated once after five minutes if needed. Where intravenous access is difficult, buccal midazolam at 0.5 mg per kg to a maximum of 10 mg is effective and was shown by the McIntyre randomised trial to terminate seizures at least as well as rectal diazepam. [3]

If the convulsion persisted despite two benzodiazepine doses, I would treat it as refractory and give a second-line agent, either intravenous levetiracetam at 40 mg per kg (maximum 2.5 g) or intravenous fosphenytoin at 20 mg PE per kg, in a high-dependency or intensive care setting with airway support. I would call for senior paediatric and anaesthetic help early. A febrile convulsion lasting over 30 minutes would be febrile status epilepticus, a neurocritical emergency. [1]

My investigation plan is selective. Because this is a complex rather than a simple febrile seizure, I would consider an electroencephalogram and neuroimaging, particularly given the prolonged duration. A lumbar puncture is not routinely required in a fully immunised child over 12 months without meningeal signs, and the 2011 AAP guideline supports observation here, but I would maintain a low threshold if his conscious state deteriorated or meningeal signs emerged. I would identify and treat the fever source (otitis media) and give antipyretics for comfort. [1]

Question 2 (10 marks)

A parent asks whether anything can be given to prevent further seizures. Discuss the evidence on prophylaxis for febrile seizures, and outline your counselling on recurrence and prognosis. [2]

I would explain that routine prophylaxis is not recommended for febrile seizures, because the evidence shows that the harms outweigh the benefits. Continuous antiepileptic prophylaxis with phenobarbitone or valproate does reduce recurrence, but phenobarbitone causes hyperactivity, irritability, and impaired cognition and behaviour in up to a third of children, and valproate carries risks of hepatotoxicity and thrombocytopenia. The American Academy of Pediatrics 2008 guideline and the 2021 Cochrane review both conclude that these harms outweigh the benefit for simple febrile seizures. [2] [4]

Intermittent oral diazepam given during fever reduces recurrence modestly, but at the cost of sedation, ataxia, and the masking of a serious illness, so it is not recommended routinely. The exception is a child with prolonged or frequent recurrences, for whom I would offer a rescue benzodiazepine, either buccal midazolam or rectal diazepam, to be given at the onset of a convulsion. This is a pragmatic and evidence-supported strategy that keeps the family out of hospital and shortens the seizure. [4] [3]

I would address the antipyretic misconception directly. Rosenbloom's systematic review showed that paracetamol and ibuprofen given during a febrile illness do not prevent the recurrence of febrile seizures compared with placebo. Antipyretics are given to make the child comfortable, not to prevent another seizure, and families who understand this are spared the needless anxiety of believing that every fever must be suppressed to avert a convulsion. [5]

On recurrence and prognosis I would be reassuring but accurate. About one in three children has another febrile seizure, and the risk is higher when the first seizure occurs under 12 months, with a family history, a low fever at onset, or a short fever-to-seizure interval. The prognosis is excellent: simple febrile seizures do not cause brain damage or cognitive impairment. The lifetime risk of subsequent epilepsy is about 2 to 5 per cent, marginally above background, and higher with complex features, which his seizure has. I would give the family a written rescue plan, a safety-net, and clear advice on when to call an ambulance. [2]