Acute care of seizures of cerebral origin in children

Essentials

  • A seizure with loss of consciousness is the most dangerous form of seizures in children and requires active emergency treatment. The majority of seizures, however, are of short duration (less than 4 minutes) and end spontaneously.
  • First aid medication is necessary if the seizure does not end spontaneously in a few minutes or if the seizure recurs before the child has recovered from the previous episode.
  • A prolonged epileptic seizure is a life-threatening emergency situation that requires immediate care, and a seizure that has lasted over 5 minutes is treated like a threating status epilepticus.
  • The essential elements in the treatment are maintenance of vital functions, termination of the seizure by first aid medication and etiological investigations to allow specific treatment (e.g. central nervous system infections).
  • All seizures in a child necessitate further investigations. The only exception is a sporadic short symmetric febrile seizure (fever over 38.5°C) in a child aged 6 months to 6 years with a history of febrile seizures in close relatives. Even for them, recurrence of the seizures during the same fever episode necessitates further investigation without delay. See also (Febrile convulsions).
  • Mortality rate and the risk of disability increase if the seizure lasts for more than 30 minutes.
  • See also (Epilepsy in children) for epilepsy in children.

First aid for seizures

Vital functions

  • Maintenance of vital functions: unobstructed airways (suction if necessary, oropharyngeal airway), lateral position, supplemental oxygen by mask
  • Measurement of blood pressure, pulse, and oxygen saturation (SpO2), immediate test for blood glucose

Lowering body temperature

  • Remove warm clothes, no physical cooling.
  • Give usual antipyretic drugs (Febrile convulsions) to reduce fever but only after anticonvulsive medication (see below) has been administered.

Placement of an intravenous line

  • Start an intravenous line if it can be done easily. Take a sample for the determination of blood glucose and electrolyte concentrations.
  • First medications are administered either buccally or rectally; see below.
  • For i.v. infusion, use physiological saline solution without glucose (unless the child is hypoglycaemic), or a Ringer-type solution.
  • Avoid excess fluids. A safe maintenance infusion rate is 0.1 ml/kg/min.

Medication

Benzodiazepines

  • Either buccal midazolam [Evidence Level: B] or rectal diazepam can be used as first aid medication before an intravenous line has been placed.
  • For buccal dosage of midazolam, see table T1.

Table 1. Buccal dosage of midazolam.
Weight (age) Dose mg
5–10 kg (6–12 months) 2.5 mg
11–20 kg (1–4 years) 5 mg
21–40 kg (5–9 years) 7.5 mg
> 40 kg (> 10 years) 10 mg
  • Single dose of rectal diazepam:
    • 5 mg for children weighing < 15 kg (aged 0–3 years) and 10 mg for children weighing > 15 kg (aged over 3 years).
    • A therapeutic serum concentration of diazepam is reached in about 5 minutes after the administration of the rectal solution. Suppositories are absorbed poorly – do not use them!
  • The buccal or rectal dose may be repeated once if needed, if no intravenous line has been established.
  • After an intravenous line has been placed the first aid medication is continued with an i.v. benzodiazepine (lorazepam, diazepam, or clonazepam).
    • Single intravenous dose of lorazepam and clonazepam is 0.1 mg/kg, maximum single dose being 4 mg.
      • The advantage of these drugs as compared to diazepam is a longer duration of action.
      • The IV solution may also be administered rectally with the same dosage.
    • Single intravenous dose of diazepam is 0.3 mg/kg, the maximum single dose being 10 mg.
      • The maximum cumulative dose (p.r. plus i.v.) is 1 mg/kg up to 20 mg, i.e. max. 20 mg.
  • Keep in mind that all benzodiazepines may cause respiratory depression. These drugs should always be given slowly within 2–3 minutes. Be always prepared to assist ventilation.

Evidence Summaries

Laboratory tests and other procedures needed immediately

  • Determination and correction of blood glucose
    • If the child has hypoglycaemia (blood glucose below 4 mmol/l), infuse 10% glucose solution i.v. 2 ml/kg within 3–4 minutes. Monitor the blood glucose concentration.
  • Laboratory tests
    • CRP, sodium, potassium, blood glucose, haemoglobin, leukocytes, calcium, blood gases (Astrup). Do not wait for test results before transporting the patient to a hospital.
  • Hypocalcaemia
    • If there is a strong suspicion of hypocalcaemia, 10% calcium gluconate may be given i.v. (dose 0.5 ml/kg infused over 5 minutes) after the blood sample for determining plasma calcium has been taken. Always monitor ECG during calcium infusion.
  • Etiological investigations (e.g. a central nervous system infection, increased intracranial pressure) as soon as the child has been hospitalized

Treatment of prolonged seizures

  • If the seizure continues despite maximum benzodiazepine dose, lowering of temperature and treatment of hypoglycaemia and hypocalcaemia (if present), continue with the second-line intravenous medication.
  • For the second-line medication, levetiracetam or fosphenytoin, sometimes, especially in infancy, phenobarbitone may be chosen.
    • Levetiracetam 100 mg/ml is diluted with 0.9% NaCl to a concentration of 40 mg/ml and administered as an intravenous infusion in 5–10 minutes. The loading dose is 40 mg/kg, and, as necessary, an additional dose of 20 mg/kg up to the maximum dose of 3,000 mg.
    • Fosphenytoin (Pro-Epanutin®) is a prodrug of phenytoin. The solution contains 75 mg/ml of fosphenytoin, which is equivalent to 50 mg/ml of phenytoin (mg FE = phenytoin equivalents). All doses are given in phenytoin equivalents (mg FE).
      • The loading dose is 17–20 mg FE/kg, and the infusion rate is 2–3 mg FE/kg/min, max. 150 mg FE/min. For dosing and infusion rate, see table T2.
      • The drug may also be given as an intramuscular injection (no more than 10 ml in one injection site); a therapeutic concentration is reached in about 30 minutes from the administration.
      • The safety and efficacy of fosphenytoin has not been verified in children below 5 years of age.
      • ECG monitoring is necessary during i.v. infusion and for 30 minutes after its end (risk of arrhythmias).
    • The loading dose of phenobarbital is 15 mg/kg (maximum single dose 500 mg), given slowly i.v. with a speed of 30 mg/min (maximum speed 100 mg/min).

Table 2. Pro-Epanutin ® loading doses
Weight (round upwards) Dose approximately 15 mg FE/kg The amount of Pro-Epanutin® (50 mg FE/ml) NaCl 0.9% or G5% Volume of dilution Infusion rate Infusion time approximately
5 kg 75 mg FE 1.5 ml 6 ml 7.5 ml 65 ml/h 7.5 min
7.5 kg 125 mg FE 2.5 ml 10 ml 12.5 ml 100 ml/h 7.5 min
10 kg 150 mg FE 3 ml 12 ml 15 ml 140 ml/h 6.5 min
12.5 kg 200 mg FE 4 ml 16 ml 20 ml 195 ml/h 6 min
15 kg 225 mg FE 4.5 ml 18 ml 22.5 ml 230 ml/h 6 min
17.5 kg 275 mg FE 5.5 ml 22 ml 27.5 ml 285 ml/h 6 min
20 kg 300 mg FE 6 ml 6 ml 12 ml 125 ml/h 6 min
25 kg 375 mg FE 7.5 ml 7.5 ml 15 ml 150 ml/h 6 min
30 kg 450 mg FE 9 ml 9 ml 18 ml 185 ml/h 6 min
35 kg 525 mg FE 10.5 ml 10.5 ml 21 ml 210 ml/h 6 min
40 kg 600 mg FE 12 ml 12 ml 24 ml 250 ml/h 6 min
45 kg 675 mg FE 13.5 ml 13.5 ml 27 ml 280 ml/h 6 min
= 50 kg 750 mg FE 15 ml 15 ml 30 ml 320 ml/h 6 min
Max. dose 750 mg FE Concentration < 20 kg 10 mg FE/ml, > 20 kg 25 mg FE/ml Infusion rate max. 3 mg FE/kg/min
  • A seizure lasting longer than 30 minutes is associated with a risk of cerebral oedema. It is prevented with the following measures:
    • restriction of fluids (no more than 75% of the basic requirement)
    • do not give hypotonic solutions
    • give furosemide 1 mg/kg i.v.
    • raise the patient to an elevated position (30 degrees), with the head in mid-position.
  • Start arranging for transport to intensive care in a hospital simultaneously with the procedures described above.
    • As a seizure lasting longer than 1–2 hours may cause permanent brain damage, there is an urgent need for initiating intensive care (usually thiopental anaesthesia).

Transport to hospital

  • After a prolonged seizure or if the seizure is not stopped by the means described above, immediate transport under the supervision of a qualified person, preferably a physician, to the nearest hospital with preparedness for paediatric intensive care is always necessary.
    • The patient should be in lateral position during the transport to minimize the risk of aspiration. Vital functions should be monitored.
    • The means for suctioning airways, supplying extra oxygen, assisting respiration and administering additional drugs should be provided for the transport.
  • Urgent or, if needed, emergency referral for further investigations and follow-up at a hospital is necessary even after brief seizures if the child has not had seizures before.

Further investigations

  • After the first seizure, a paediatric neurologist or a paediatrician should always examine the child to establish aetiology and plan the prevention of further seizures. The only exception from this rule are the short typical febrile seizures (Febrile seizures). Instructions concerning first aid and medication are sufficient in that situation. Recurrence of febrile seizures may warrant further investigation.
  • Also absence seizures, attacks of blurred consciousness, seizures with only motor symptoms without disturbance of consciousness and seizures with myoclonic jerks require emergency investigations and treatment if they are prolonged or if the child has other symptoms suggesting e.g. an infection. The cause of short seizures in a child should be investigated without delay even if the child is in good general condition.
  • If the child is known to have epilepsy, he/she may be discharged home after a short seizure that was typical to the child, provided that he/she has fully recovered from the seizure. Otherwise the child should be referred to hospital for further investigations on emergency basis.
  • If the child is discharged home after a seizure, it is important to exclude any serious illness such as meningitis, encephalitis or a systemic disease.
    • This requires a sufficiently long follow-up after the seizure, clinical examination and, if needed, laboratory tests.
    • Bacterial meningitis may be a background factor in as many as 17% of cases of prolonged seizures occurring in association with fever in infants.

References

1. McIntyre J, Robertson S, Norris E, et al. Safety and efficacy of buccal midazolam versus rectal diazepam for emergency treatment of seizures in children: a randomised controlled trial. Lancet 2005 Jul 16-22;366(9481):205-10  [PMID:16023510]
2. Chin RF, Neville BG, Scott RC. Meningitis is a common cause of convulsive status epilepticus with fever. Arch Dis Child 2005 Jan;90(1):66-9  [PMID:15613516]
3. Chamberlain JM, Kapur J, Shinnar S, et al. Efficacy of levetiracetam, fosphenytoin, and valproate for established status epilepticus by age group (ESETT): a double-blind, responsive-adaptive, randomised controlled trial. Lancet 2020;395(10231):1217–1224.  [PMID:32203691]
4. Dalziel SR, Borland ML, Furyk J, et al. Levetiracetam versus phenytoin for second-line treatment of convulsive status epilepticus in children (ConSEPT): an open-label, multicentre, randomised controlled trial. Lancet 2019;393(10186):2135–2145.  [PMID:31005386]

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