Pediatric Small Talk – The FAQ Approach to Simple Febrile Seizures

Welcome back to Small Talk.  Every first Wednesday of the month we will release high yield PEM content written by PEM talent from around the country.  We hope you enjoy these reviews. Comments, questions, accolades or concerns: feel free to reach out to Joe Ravera, MD (pemgemspod@gmail.com).

Authors: Tamara Casas, MD (EM Resident Physician, UC San Diego Health); Joe Ravera, MD (@pemuvm1, Director of Pediatric Emergency Medicine, UVM Medical Center, Assistant Professor of Surgery, UVM College of Medicine); Kristy Schwartz, MD, MPH (@kaynani32, Assistant Program Director Emergency Medicine, Assistant Health Sciences Clinical Professor, Departments of Pediatrics and Emergency Medicine, UC San Diego) // Reviewed by: Alex Koyfman, MD (@EMHighAK); Brit Long, MD (@long_brit)

Case: 

An 18-month-old male presents to the ED with his parents for evaluation of seizure. His mother is at bedside providing the history. She states the patient had a runny nose beginning yesterday. This morning, he woke up and “felt warm” when he woke up but she did not take his temperature. About 20 minutes later, she noticed he was “out of it” and was “shaking all over.” She panicked and called 911 immediately. She thinks the shaking lasted about 2-4 minutes. By the time paramedics arrived, he had stopped shaking but was very sleepy. The patient’s blood glucose was 95. His temperature was 102 F (38.9 C) and they transported on pulse oximetry, which was normal en route. The patient is back to his baseline now and playing.

The patient’s parents report he was born full term with no complications in pregnancy or delivery. No recent travel or sick contacts.  His vaccines are up to date.

Vital Signs:

Temp: 101.1 F/38.4 C (rectal)

BP: 90/56

HR: 130 BPM

RR: 24

O2 Sat: 100% on RA

Physical Examination:

Well appearing and interactive male in no acute distress. Notable nasal congestion and hyperemic mucosa in nares. Ranges head/neck without distress. Lungs clear to auscultation bilaterally with no respiratory distress. No rash noted throughout. No focal neurologic deficit.

The parents are extremely distraught and ask you to “test for everything”.

The Initial Evaluation of a Child with a Febrile Seizure

The initial evaluation of a child with a febrile seizure, like most things in EM, should start with the ABCs. A child who is still actively seizing requires treatment as we would treat in other patients in status epilepticus with IV benzodiazepines and second line agents such as levetiracetam or fosphenytoin.^1-4

A child who is post ictal but returning to baseline should be closely monitored for return to baseline.

However, in most instances the child with the simple febrile seizure is at or near baseline by the time of the emergency department evaluation. The question then becomes what is the appropriate management for a child who has a febrile seizure and is now back to baseline?

Differentiating simple from complex

The first step in evaluation typically involves differentiating simple from complex. First, there must be an absence of neurologic infection (meningitis/encephalitis), underlying metabolic derangement, or history of afebrile seizures. Absent those, there are several features of the seizure itself which differentiate simple from complex. (Figure 1) Approximately 20% of febrile seizures are complex and their work up is typically more involved including laboratory studies, neuroimaging, and CSF sampling. It should also be noted that complex febrile seizures are not only more likely to recur, but also have higher risk of subsequent epilepsy.^5,6

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A Stepwise Approach to the Patient with a Simple Febrile Seizure

Step 1: Acknowledge the Family’s Fears

Oftentimes these events are extremely traumatic to parents and caregivers.  It is not uncommon to hear the parents say something along the lines of “I thought my kid was going to die”.  Taking a moment to acknowledge how traumatic this event is, can be a good first step in providing reassurance.

Step 2: The Work Up

Parents will often ask “what is the appropriate work up”.  Luckily, the work up for a simple febrile seizure is the same as the age appropriate fever work up for that child.  This involved a good history and physical exam and consideration of bacterial sources of infection (such as pneumonia or UTI).  It should be noted that similar to most well appearing, vaccinated children with a short duration of fever most children with a simple febrile seizure do not require screening laboratory studies or CSF sampling.⁷

Step 3: The Frequently Asked Question

After an acknowledgement of the parents’ fears, and age appropriate fever work up the rest of the visit typically focuses on parental education and resources which can come in the form of a “febrile seizure speech” which often involves answering the frequently asked questions.

How common is this and what caused it? 

Febrile seizures are relatively common and occur in children between 6 months and 5 years of age and are associated with fever (temp >38C). It is the most common pediatric convulsive disorder and affects 2-5% of children in the United States. Usually, febrile seizures will be seen with common childhood infections such as: acute otitis media, upper respiratory infections, roseola, or GI infections. Patients with family history of febrile seizures and developmental delay are more likely to develop febrile seizures.^6,8,9

Will it happen again?

Children with a first presentation of simple febrile seizures have an approximately 30% risk of recurrence. For a child who has had multiple febrile seizures the risk of recurrence is higher, and can be as high as 70%.^6,8,9

Can these be prevented with prophylactic antipyretics or anti-epileptic drugs (AEDs)?

Given the traumatic effect on the parents there will often be an urge to “do something” going forward. It is important to emphasize that missed antipyretic doses when a child has a fever did not cause their child to seize. There is strong evidence that prophylactic antipyretics do not prevent the occurrence of febrile seizures during illness.^10,11

Interestingly, while prophylactic antipyretics are not effective there is a risk reduction if the child takes AEDs prophylactically.  However, the most recent review pointed out that nearly 30% of children will experience side effects from AEDs and given that the majority of febrile seizures are benign, prophylactic AEDs are not routinely recommended.¹²

What are the long-term effects?

The honest answer is that children are at increased risk for epilepsy compared to the general population rate of approximately 1%. Only ~2.4% of children with simple febrile seizures will develop epilepsy. While this is a two-fold risk increase, the absolute risk increase is relatively small.^6,8,9

There is often a parental concern about long term neurocognitive effects.  This has also been well studied and in multiple trials there is not a discernible neurocognitive difference in children who have had febrile seizures.¹³

Disposition

Most patients who develop simple febrile seizures can be discharged after a short period of monitoring in the emergency room. Review appropriate antipyretic dosing and seizure basic life support with the parent/guardian. If a patient returns to baseline mental status and does not have recurrent seizures while in the ED, they can be discharged with reassurance and anticipatory guidance to parents.^6,8,9

Take Home Points

-The classification of simple vs. complex febrile seizure is essential for management and prognosis

-The evaluation of a child with a simple febrile seizure is the same as the age-appropriate work up for a febrile child

-These events can be extremely distressing to parents and parental reassurance and education are the cornerstones of management

–Most children can be discharged after a short period of observation

Case Concluded

Within 30 minutes the child is back to baseline and running around the room.  You pull up a chair next to the parents and explain this was a simple febrile seizure.  You acknowledge their fears, explain the age appropriate fever work up, go over the frequently asked questions and answer any other questions.  The parents thank you for taking the time to explain and the child and family leave happy.

References

1.  Zhao ZY, Wang HY, Wen B, Yang ZB, Feng K, Fan JC. A Comparison of Midazolam, Lorazepam, and Diazepam for the Treatment of Status Epilepticus in Children: A Network Meta-analysis. J Child Neurol. 2016 Aug;31(9):1093-107. doi: 10.1177/0883073816638757. Epub 2016 Mar 28. PMID: 27021145.
2. Lyttle MD, Rainford NEA, Gamble C, et al. Levetiracetam versus phenytoin for second-line treatment of paediatric convulsive status epilepticus (EcLiPSE): a multicentre, open-label, randomised trial. Lancet. 2019;393(10186):2125-2134. doi:10.1016/S0140-6736(19)30724-X
3. Dalziel SR, Borland ML, Furyk J, Bonisch M, Neutze J, Donath S, Francis KL, Sharpe C, Harvey AS, Davidson A, Craig S, Phillips N, George S, Rao A, Cheng N, Zhang M, Kochar A, Brabyn C, Oakley E, Babl FE; PREDICT research network. Levetiracetam versus phenytoin for second-line treatment of convulsive status epilepticus in children (ConSEPT): an open-label, multicentre, randomised controlled trial. Lancet. 2019 May 25;393(10186):2135-2145. doi: 10.1016/S0140-6736(19)30722-6. Epub 2019 Apr 17. PMID: 31005386.
4. Chamberlain JM, Kapur J, Shinnar S, Elm J, Holsti M, Babcock L, Rogers A, Barsan W, Cloyd J, Lowenstein D, Bleck TP, Conwit R, Meinzer C, Cock H, Fountain NB, Underwood E, Connor JT, Silbergleit R; Neurological Emergencies Treatment Trials; Pediatric Emergency Care Applied Research Network investigators. Efficacy of levetiracetam, fosphenytoin, and valproate for established status epilepticus by age group (ESETT): a double-blind, responsive-adaptive, randomised controlled trial. Lancet. 2020 Apr 11;395(10231):1217-1224. doi: 10.1016/S0140-6736(20)30611-5. Epub 2020 Mar 20. PMID: 32203691; PMCID: PMC7241415.
5. Febrile Seizures: Guideline for the Neurodiagnostic Evaluation of the Child With a Simple Febrile Seizure. (2011). PEDIATRICS, 127(2), 389–394.
6. Smith, D. K., Sadler, K. P., & Benedum, M. (2019). Febrile Seizures: Risks, Evaluation, and Prognosis. American Family Physician, 99(7), 445–450.
7. Cioffredi LA, Jhaveri R. Evaluation and Management of Febrile Children: A Review. JAMA Pediatr. 2016 Aug 1;170(8):794-800. doi: 10.1001/jamapediatrics.2016.0596. PMID: 27322346.
8. Berg, A. T., Shinnar, S., Shapiro, E. D., Salomon, M. E., Crain, E. F., & Hauser, W. A. (1995). Risk Factors for a First Febrile Seizure: A Matched Case-Control Study. Epilepsia, 36(4), 334–341.
9. Annegers, J. F., Hauser, W. A., Shirts, S. B., & Kurland, L. T. (1987). Factors Prognostic of Unprovoked Seizures after Febrile Convulsions. New England Journal of Medicine, 316(9), 493–498.
10. van Stuijvenberg M, Derksen-Lubsen G, Steyerberg EW, Habbema JD, Moll HA. Randomized, controlled trial of ibuprofen syrup administered during febrile illnesses to prevent febrile seizure recurrences. Pediatrics. 1998 Nov;102(5):E51. doi: 10.1542/peds.102.5.e51. PMID: 9794981.
11. Strengell T, Uhari M, Tarkka R, Uusimaa J, Alen R, Lautala P, Rantala H. Antipyretic agents for preventing recurrences of febrile seizures: randomized controlled trial. Arch Pediatr Adolesc Med. 2009 Sep;163(9):799-804. doi: 10.1001/archpediatrics.2009.137. PMID: 19736332.
12. Offringa M, Newton R, Cozijnsen MA, Nevitt SJ. Prophylactic drug management for febrile seizures in children. Cochrane Database Syst Rev. 2017 Feb 22;2(2):CD003031. doi: 10.1002/14651858.CD003031.pub3. Update in: Cochrane Database Syst Rev. 2021 Jun 16;6:CD003031. PMID: 28225210; PMCID: PMC6464693.
13. Chang YC, Guo NW, Huang CC, Wang ST, Tsai JJ. Neurocognitive attention and behavior outcome of school-age children with a history of febrile convulsions: a population study. Epilepsia. 2000 Apr;41(4):412-20. doi: 10.1111/j.1528-1157.2000.tb00182.x. PMID: 10756406.