Interesting Case:

KM, Sunday July 18th

Dr. Mabom

You are on your second night shift at Children’s, and you’ve just finished seeing your third case of gastro that night. Suddenly you hear overhead, trauma team to the trauma room, Dr. To the trauma bay STAT. Of course, you go running too.

As you enter the trauma bay, a 21 month female is being transferred onto the bed by EMS. She is seizing, but is breathing on her own. The team gets to work getting her on the monitor, oxygen, and establishing IV access. In the meantime, you get the snapshot history from EMS:

They responded to the call at about 0320. The father had been sleeping beside the bed, and halfway through the night took the patient in his lap to sleep. He awoke to some abnormal movements, and found her seizing, with tonic, clonic movements. Her eyes were initially fixed upwards.He is unsure of when it actually started. When EMS arrived, she stopped seizing, but then started again about a minute later. She was given 2.4mg midaz IM, which slowed down the seizure for about 10min but did not stop it. Before arrival at ACH she received another 2.4mg IM midaz. The patient has been seizing for about 45 minutes and the patient, while no longer clonic, is hypertonic and convulsing every couple of minutes.You get a snapshot history from EMS; previously well, fine yesterday, but developed a fever in evening of ~39, dad thinks she maybe has an ear infection.

On exam:

  • You pry open her eyes and find Pupils 4 reactive, not deviated
  • GCS: not combative, no eye opening, no crying, even with the IV poke.
  • Arms and legs are hypertonic, you can just overcome them to bend them. Frequent convulsions noticed. Arms are in decorticate posturing. Can’t get any reflexes.
  • SaO2 93% NP
  • Nothing else remarkable

R1 question: what is your immediate concern in this patient?

A)Airway – she is actually obstructing, making snoring noises. A simple jaw thrust stops the obstruction, her sats climb. You can’t put an oral airway in because her jaw is clenched shut.

She is now hooked up to the monitor and you have your first set of vitals: 38.5 / 31 / 192 / 128/88 / 99 NRB

R2 question: is there anything else you want immediately? (ie POCT)

A)Her BG is 3.6. You give her 30cc of 25% dextrose. D25W can be made by diluting 15cc D50W 1:1 with 15cc NS. (0.5-1g/kg, or using D25W 2-4ml/kg). Repeat BG a bit later is normal.

You now have IV access. You ask the nurse to draw up several medications, and start running a 20cc/kg bolus. She continues to seize.

R3 question: What meds are you going to use?

A)She is given lorazepamto a total of 3.5mg.

  1. If we couldn’t get IV access, we could have used PR diazepam 0.5mg/kg. Diastat is the rectal preparation. If not available, place a feeding tube 4-6cm into the rectum and run in the IV diazepam.

B)You load her with 20mg/kg phenytoin. This actually takes some time to do. She weights 12kg so the dose needed is 240mg. The bolus runs at 1mg/kg/min, so in her it would be 12 mg/min, which takes a total of 20 minutes to infuse. Dilantin acts to attenuate seizures by sodium channel blockade, stabilising neuronal membranes in the CNS. By itself it doesn’t cause respiratory depression or sedation, but it is diluted in propylene glycol which can cause hypotension. If the later occurs, just slow down the infusion rate. Time to action is 10-20 minutes

C)She is also given a bolus of NS, then run D5 1/2NS at maintenance

D)Ceftriaxone also given

Despite 5mg midazolam, 3.5mg ativan, loading with phenytoin underway, she continues to seize. She remains unresponsive, breathing spontaneously but still obstructing, no eye opening, no crying. Occasionally after a dose of ativan she bats her arms and legs - ? purposeful movements? But then is back to her previous LOC. You decide to intubate her.

EM question: We just had our airway session this week. What are our indications for intubating this patient?

A)Expected clinical course – we are going to need more benzos to control her seizure

B)Airway compromise – we already cannot use an oral airway, she has decreased LOC.

Peds fellow question/R4/R5: What is your approach to intubating this patient? What are you going to use? There were no concerns this would be a difficult airway, you have all of your equipment already set up.

A)Premedicate: we opted to use atropine 0.01mg/kg (0.12mg), the doc I was working with uses it in all infants and neonatal intubations

B)Induction: we already did our induction – midaz, lorazepam, already altered. We gave her another 1.5 midaz.

C)Paralysed her with succ. Of course, didn’t want to use a long acting neuromuscular blocking agent, because we would be unable to determine if she was seizing, unless we had continuous EEG monitoring.

She was successfully intubated and by the time the succ wore off the dilantin had finished infusing. Shortly after this, 1 hour after onset, she finally stopped seizing. She was kept sedated with midaz.

The patient has a secure airway, is ventilating, and hemodynamically stable, no longer seizing. ICU has just come down to see the patient, and they will be transporting the child to the PICU soon. You finally get a chance to chat with the mother about what had happened.

The patient is a healthy 21 month female. She is developmentally normal with no prior illnesses or even visits to the hospital. No history of OM, pneumonia, she is vaccinated and does not attend daycare. There is no family history of epilepsy or seizure disorders, and she has a 4 year old son who is well. Yesterday she was well, except that half way through the day she began to get a fever, but mom didn’t think too much of it. She took her temp, which was 39, and the child went to bed without event. Mum got up to check on her in the middle of the night to check up on her and she found her to be seizing. The patient did not get into any toxins that mom knows of, no trauma. Mum is currently taking amox for a sinus infection, and worried because she is still breastfeeding occasionally.

R4/R5 question: Based on the history and clinical scenario, what is your differential of the etiology of this seizure episode?

  • Infectious:
  • Meningitis
  • Encephalitis, incl HSV
  • Brain abcess
  • Febrile seizures
  • Complex
  • Febrile status epilepticus
  • Metabolic disturbance:
  • Lytes, hypoglycaemia
  • CNS neoplasm:
  • Unusual in peds because tumors more commonly intratentoral and rarely cause seizures
  • Vascular:
  • AVM
  • Drugs: TCA, anti-histamines, stimulants, hypoglycaemic agents

To help determine the diagnosis, the patient had numerous investigations, some in the ED and some in the ICU. She was extubated the next day and transferred to the ward. Seen by neurology, who were not concerned this was meningitis, or anything else other than complex febrile seizure

  • Bloodwork: CBC normal, lytes normal, LFT, CRP/ESR
  • Urinalysis normal
  • Pancultures no growth (urine, CSF, bloodx2)
  • CXR: R mainstem intubation, but otherwise nil acute
  • Q: what is wrong with this picture???
  • Braslow has preset depth at teeth the EET should rest to avoid this. Takes 2 seconds for some one to grab in a chaotic situation (the tube should have been 12.5-13.5 at the teeth!)
  • CT head: nil acute
  • LP: normal
  • EEG: normal, some central spikes seen. Neurologist commented this is normally seen in an EEG performed pos- ictally

Final diagnosis: status epilepticus; febrile generalised tonic-clonic status eoilepticus

Patient was discharged home with no neuro follow up. The fever of unknown origin was attributed to a viral illness, and her hypoglycaemia at presentation secondary to a prolonged seizure state.

Prescribed abortive benzodiazepine, Lorazepam 0.1mg/kg 4 doses and parents were instructed on how administer.

Management of status epilepticus:

1)ABC’s and D (for dextrose), monitors, IV access, STAT cap gas, glucose

2)First line – BDZ:

  1. Lorazepam 0.5-0.1mg/kg IV/IO
  2. Diazepam 0.2-0.5mg/kg IV/IO/PR
  3. Midazolam 0.2mg/kg IV/IM
  4. If seizure persists, repeat dose of BDZ

3)Phenytoin/Phosphenytoin

  1. Indicated if seizure persists despite BDZ and repeat dosing is needed
  2. Phenytoin: 20mg/kg run at 1mg/kg/min, can give another 10mg/kg dose if needed.
  3. Phosphenytoin: 20PE/kg run at 150mg/min (runs faster than phenytoin)

4)Barbituates:

  1. Phenobarbital: 20mg/kg, usually for children already on phenytoin
  2. Must monitor hemodynamics and respiratory status more carefully, as more easily and less predictably depressed.

5)ICU

  1. Pt will be intubated with EEG monitoring
  2. Levitaracetam (keppra) 20-30mg/kg IV
  3. Valproic acid 20-30mg/kg IV
  4. propofol

Febrile Seizures:

  • Most common type of seizure in children. 2-5% of all children in NA and Europe will have a febrile Sz, occurring usually between 6 months and 5 years of age.

Simple Febrile Seizure:

  • A seizure occurring in the presence of a fever without CNS infection or other cause.
  • Features:
  • Generalised
  • Less than 15 min
  • Occur in a child between 6 months – 5 years
  • Developmentally and nwurologically normal child
  • 30% of children with FSz will have recurrent FSz with future febrile illnesses
  • Managment Principles:
  • Febrile seizure is a diagnosis of exclusion after considering and looking for more sinister causes of seizure in the context of a fever.
  • AAP recommendations:
  • No LP in a child older than 18 months of age
  • Consider LP in child 12-18 months
  • Strongly consider LP in 6-12months
  • EEG, neuroimaging, bloodwork not necessary
  • Determine the source of the fever – is there an infection that you need to treat ie OM?

Complex Febrile Seizure:

  • 25-30% of febrile Sz are classified as being complex.
  • Definition:
  • Partial / Focal
  • Prolonged (15-29 min, some studies use >10min)
  • Multiple episodes without recovery in the same illness
  • Febrile status epilepticus is the extreme of complex febrile seizures (30min)
  • The future risk of epilepsy is 5-10 %. This is the same risk as a simple febrile seizure with a 1st degree relative who has epilepsy, or with developmental delay pre febrile seizure.
  • Who gets complex febrile Sz?
  • Younger (<1yr)
  • Fever <102
  • Often the complex febrile seizure is the first episode of febrile seizure
  • Developmental delay
  • conflicting evidence for complexfebrile seizure
  • FSE – some series have shown statistically significant increased proportion of developmentally abnormal children
  • Fm Hx epilepsy – more likely to have prolonged and repeating complex febrile seizure
  • FSE: tend to be younger than simple febrile seizure
  • Who has recurrent complex febrile seizure?
  • Rate of recurrence is generally greater for complex compared to simple febrile seizures
  • The greater episodes of febrile seizures, the more likely to have a complex FSz
  • Children with complex FSz are more likely to have recurrent febrile seizures, but not all recurrences are necessarily complex
  • Complex feature of prolonged duration increases recurrence
  • Recurrence more likely to be prolonged
  • For this group, there is some evidence that abortive therapy may be warranted
  • Family Hxepilepsy, has been associated with prolonged, recurrent complex FSz.

Febrile Status Epilepticus

  • Definition?
  • Seizure >30 min duration, or recurrent seizures lasting >30min without fully regaining consciousness
  • Older definitions include FSE as all FSz >15min
  • PLUS inclusion for febrile Sz(seizure occurring in the presence of a fever without CNS infection or other cause, 6mo-5 years.
  • Can include developmentally abnormal children
  • Represents <5% of all febrile seizures
  • 25% of all pediatric status epilepticus
  • > 2/3 of status epilepticus in the second year of life
  • This is definitely a diagnosis of exclusion, and can be made after ruling out other causes precipitants of status epilepticus
  • The longer the seizure lasts, the less likely it is to abort spontaneously. Most stop with administration of BZD
  • M > F
  • Outcomes to febrile status epilepticus
  • FSE is the extreme spectrum of febrile seizures. If there is sequelae from febrile seizures, it should be seen in this subgroup.
  • Short Term Outcomes (first few months after seizure):
  • Most of the series done over the last 20 years have demonstrated very little mortality and morbidity. There is no increased mortality or motor and cognitive deficits compared to control simple febrile seizure subjects. This is true for developmentally delayed children, no worsening of their baseline cognitive levels.
  • Longer Term Outcomes (up to 3 years after seizure)
  • There are no studies to date looking at outcomes from FSE into adulthood
  • No neurological sequelae – no new or worsening baseline neurological abnormalities in the years after the seizure
  • Future seizures:
  • Developmentally delayed patients: increased risk of future febrile and afebrile seizures (40-50% will get future febrile seizures). Also increased risk in children <1 year, attributable to undiagnosed CNS abnormalities compared to older children. Some suggestion that there is an increased risk of febrile seizures is patients with family history of epilepsy, but not to afebrile seizures.
  • Developmentally normal children: no increased risk of afebrile seizures or epilepsy
  • afebrile seizures / epilepsy: Verdict is still out to exact risk. Risk is at least that of complex febrile seizures, but not sure how much higher, or the additional severe risk of MTS/MTLE
  • Mesotemporal Lobe Sclerosis (MTS)/Mesotemporal Lobe Epilepsy (MTLE):
  • Possible association with mesotemporal lobe sclerosis, and mesotemporal lobe epilepsy
  • Case reports demonstrating this effect. No prospective and adequately powered studies examining this.
  • Postulated that prolonged seizures are associated with more scarring / epilepsy.
  • These case reports also showed evidence of pre-existing damage, meaning that some temporal lobes may be more susceptible or even predispose to status epilepticus in the context of the fever.
  • Currently a large ongoing prospective study enrolling patients with febrile status epilepticus, to follow them longitudinally. There is no real consensus to this issue and an area of ongoing study and debate.

Diagnostics in complex febrile seizures / febrile status

  • This is an area of some debate. Our patient received a CT scan, EEG, and an LP, which all come with their own risks and benefits. There are clear guidelines for simple febrile seizures, but none for complex febrile seizures. Below is a summary from studies looking at complex febrile seizures. For febrile status, there is no concensus as to appropriate workup, and must be done on a case by case basis.
  • Neuroimaging:
  • Numerous studies, mainly retrospective, looking at abnormalities on neuroimaging after complex febrile seizures in otherwise well appearing children
  • None show any intracranial pathological condition requiring emergent neurosurgical or medical intervention (hemorrhage,mass, edema).
  • Some studies report on non-emergent findings such ashippocampal injury, which may be significant for development of epilepsy.
  • This suggests that imaging is unnecessary for most complex febrile seizures, in the non-toxic child.
  • Did not find any studies specifically looking at febrile SE, but the studies I looked at did not exclude complex seizures >30min
  • LP:
  • Well known correlation between acute bacterial meningitis and seizures
  • In complex febrile seizures in the otherwise well looking child, LP has very low yield of ABM. These studies did not comment on encephalitis / viral meningitis.
  • An article in Pediatrics June 2010 found 0.9% incidence of ABM in 526 patients. Out of the 3 cases, 2 were toxic at presentation, and 1 was a well appearing child.
  • LP does not need to be routinely performed in all cases of complex febrile seizure, but like everything else used in conjunction with clinical judgment.
  • EEG:
  • 1recent review (Brain & Development 2010;32:31) on EEG in complex febrile seizures and febrile status epilepticus. Examined studies from 1940’s to 1970, the only ones available specifically looking at this topic.
  • EEG generally performed within a week of the seizure. They often do show some abnormality, most commonly focal slowing. Drastically different rates of subsequent epilepsy are reported with this same EEG pattern.
  • Most studies were done decades ago, when MRI was not around to correlate abnormalities on EEG to CNS lesions.
  • Not enough evidence to say don’t get the EEG after a complex febrile sezure.

Future Risk of Epilepsy:

  • Baseline population: 1% baseline risk in general population of developing epilepsy
  • Simple febrile seizure: 2-10% children will go on to have a non-febrile Sz
  • Complex febrile seizure:5-10 % (also risk if 1st degree relative, develop delay pre-Sz)
  • Febrile status Epilepticus:developmentally delayed and children <1 years are more likely to develop epilepsy and have significantly more febrile seizures. Developmentally normal children do not appear to have significantly increased risk of epilepsy, exact risk not known.