Pediatric Neurologic Emergencies
description
Transcript of Pediatric Neurologic Emergencies
Pediatric Neurologic Emergencies
Leybie AngJuly 31 2008
Objectives
Febrile Seizures
Status Epilepticus
Encephalitis
FEBRILE SEIZURE
Case Presentation
16 month old, former 38 weekerPreviously healthyBrought in by EMSSeizure activity at homeLasting 1-2 minutesArms and legs twitching3 days hx of URI symptoms
Febrile Seizure – Definition
NIH definition An event in infancy or childhood usually
occurring between 3 month and 5 year of age, associated with fever but without evidence of intracranial infection or defined cause of seizure
Febrile Seizure - Incidence
2-5% in children < 5yo Up to 15%
Majority between 12-18mo One parent – 4.4xBoth parents – 20xSibling – 3.6 x Second degree relative – 2.7x
Simple Febrile Seizure
Most commonSeizure < 15 minutesNo focal featuresOnly once in 24hr time period
Complex Febrile Seizure
Episodes lasting > 15 minutesFocal features or postical paresis> 1 episode in 24 hrsSeizure in a series with total duration >
30minutes
Risk Factors For Recurrence
Low fever at time of first sz (<40)Young age (<12 month old)Family hx of febrile szShort period of time between fever and sz
(<24hr)?male
Risk Factors For Developing Epilepsy
Family Hx of epilepsyComplex featuresPresence of early onset
neurodevelopmental abnormalies
Febrile Seizure - Immunization
Risk of febrile seizure increasesBy 1.5 fold on day of DTP immunization
Risk now reduced if DTaP Acellular pertussis instead of whole cell
pertussisBy 3.0 fold with the peak occurring 1-2
weeks after MMR vaccination
Differential Diagnosis
Shaking/ChillsTraumaToxinsMetabolic disorderMeningitis/Encephalitis
Febrile Seizure - Management
A
B
C
Febrile Seizure - Management
AntipyreticsSponging Antiepileptic
Febrile Seizures – Antipyretics
Uhari et al J peds 1995 126:991 180 kids RDBPC (plac + plac, plac + acet, diaz + acet, diaz + plac) no difference in recurrence x2yrs
Schnaiderman et al Eur J Peds 1993 152:747 104 kids RCT acet q4h scheduled or prn, no difference
Van Stuijvenberg et al Peds 1998 102:1 230 kids RDBPC ibuprofen to plac no diff X1yr
Febrile Seizure - Antipyretics
Meremikwa et al Cochrane Database 2002 Systematic review of 12 trials acetaminophen
vs placebo +/-sponging
Insufficient evidence
Febrile Seizure - Diazepam
Dose given when: when child is febrile before start seizing or as soon as start seizing
Oral dosage given at time of fever – 44% reduction in the risk of febrile seizure per person-year with diazepam
Febrile Seizure - Phenobarbital
Effective in preventing recurrence of simple febrile seizure
Daily therapy reduced the rate of subsequent febrile seizure from 25% to 5%
Adverse effect : hyperactivity, hypersensitivity reaction (SJS), loss of
cognitive function
Febrile Seizure – Valproic Acid
As effective as phenobarbital in preventing recurrent simple febrile seizure
More effective than placebo
Side effect : Fatal hepatotoxicity (esp <3yo at greatest risk)
Febrile Seizure - Prevention
Committee on Quality Improvement Subcommitteeon Febrile Seizure of the AAP 1999 “Based on the risk and benefits of effective
therapies, neither continuous nor intermittent anticonvulsant therapy is recommended for children with one or more simple febrile seizures. AAP recognises that recurrent episodes of febrile seizures can create anxiety in some parents and their children and as such appropriate educational and emotional support should be provided”
Question #1
In the emergency department, you are talking with the parents of a 17 month old boy who was evaluated for a first generalised seizure that lasted 7 minutes and followed by a fever 102.9 F (39.4 C). Other than OM, findings on the physical examination were normal, and the child was discharged home. The child is developmentally normal. Upon examination, the child now appears well.
Of the following, your MOST likely statement to the parents is that
A. antipyretic agents are effective in preventing future febrile seizures
B. CT head is preferred to MRI brain for evaluation of this child
C. EEG is not indicated D. The chance of another febrile sz is ~50% E. The child has a 5% chance of developing
epilepsy
STATUS EPILEPTICUS
Status Epilepticus - Introduction
EFA Two or more sequential seizures without full
recovery of consciousness between seizures, or more than 30 minutes of continuous seizure activity
10-58 per 100,000 per year for children 1 to 19 year old
More common in in children with epilepsy 9-27%
Status Epilepticus - Etiology
26% acute CNS insult Bleed Trauma Infection
20% underlying seizure disorder Sudden discontinuation of meds Drug interaction Fever
53% unknown
Status Epilepticus
Status Epilepticus – Blood Culture
Should blood culture be routinely done in children in SE?
Six Class III studies, total 357 children, BC positive in 2.5%
Insufficient data to support or refute in children whether blood cultures should be done routine basis in children whom there is no clinical suspicious for infection
Status Epilepticus – Lumbar Puncture
Should LP be routinely done in children with SE?
Class III studies – out of 1,859 children 12.8% has documented CNS infection
Insufficient data to support or refute in children whether lumbar puncture should be done routine basis in children whom there is no clinical suspicious for infection
Status Epilepticus – AED Levels
Should AED levels be routinely obtained in children taking AED who develop SE?
Class II data showed that low AED levels in 32% of children on AEDs
AED levels should be considered when a child with epilepsy on AED prophylaxis develops SE
Status Epilepticus – Toxicology Testing
Should toxicology testing be routinely ordered in children with SE?
Class III studies showed that a diagnosis of ingestion in 3.6%
Toxicology testing maybe considered in children with SE, when no apparent etiology is immediately identified.
Specific serum toxicology level is required
Status Epilepticus - EEG
Should an EEG be routinely performed in the evaluation of a child with SE?
Class III studies reported that abnormal brain activity on 43.1% of EEG done on SE
EEG may be considered in a child with new onset SE
Status Epilepticus – Imaging
Neuroimaging may be considered for the evaluation of the child with SE if there are clinical indications or if the etiology is appropriately stabilised and the seizure activity controlled
Imaging - CT vs. MRI
MRI useful for: More detailed view of brain anatomy Better screen for CNS malformations and
dysplastic lesions, temporal lobe (esp. hippocampus)
CT useful for: Larger neoplasms, old infarctions, major
malformative processes Assessment of the critically ill child
Status Epilepticus - Managemnet
A
B
C
SE treatment
1st line anticonvulsants IV
Lorazepam 0.1mg/kg Diazepam 0.2 mg/kg Midazolam 0.2 mg/kg
Rectal diazepam 2-5 yrs – 0.5 mg/kg 6-11 yrs – 0.3 mg/kg >12 yrs – 0.2 mg/kg
IM, intranasal, buccal midazolam
SE treatment
2nd line agents Phenytoin 20 mg/kg @ 1mg/kg/min (upto 50 mg/min) Fosphenytoin 15-20 PE/kg @ 3 mg/kg/min (upto 150
mg/min)
3rd line agents Phenobarbital 20mg/kg @ 100mg/min Repeat prn 5-10mg/kg Maximum 40 mg/kg or 1 gram
Refractory SE treatment
Consider midazolam 0.2 mg/kg bolus 1-10 mcg/kg/min infusion
Induce barbiturate coma Pentobarbital 5-15 mg/kg @ 25 mg/min Then 1-5 mg/kg/hour
Others Valproic acid Paraldehyde, chloral hydrate Propofol, inhalational anesthesia, paralysis lidocaine
Status Epilepticus - Complications
Hypoxia Impaired ventilation Increased secretions Increased O2 consumption Impaired O2 delivery Metabolic and respiratory acidosis
Brain injury Hypoxia and hypoperfusion MR, behaviour changes, neuro deficits
Status Epilepticus - Complications
Morbidity< 1yo - 30% > 3yo – 6%Mortality
3%
Question #2
A 8 month old girl is brought into the emergency department in status epilepticus. She has had diarrhea for the past 4 days. The infant had received bottled water for the past 3 days of her illness and cola for the past 24hr.
Of the following, the MOST likely cause of her status epilepticus is
A. HypocalcemiaB. HypoglycemiaC. HypokalemiaD. HypomagnesemiaE. Hyponatremia
ENCEPHALITIS
Case Presentation
16 yo old female presents with fever, headache, neck stiffness, swallowing difficulties and altered mental status
Symptoms have worsened over past 2 days.
Roommate noted a change in behaviour for the past week
2 weeks ago had a bad URTI- missed 2 days of school
Encephalitis
Defined as acute CNS dysfunction with radiographic or laboratory evidence of brain inflammation
1. Primary Encephalitis cause bloodstream infection, then enter the CNS
2. Post- or Parainfectious not caused by direct CNS infection consequence of the host’s immune response
Encephalitis
HSV - typically infects neurons in the temporal lobe
Rabies - predominantly affects the pons, medulla, cerebellum, and hippocampus
Japanese encephalitis virus affects the brainstem and basal ganglia.
Post- Parainfectious Encephalitis
occurs days to weeks after the onset of an infection
hypothesized to be caused by an aberrant immune response against brain antigens such as myelin basic protein
Subsequent demyelination causes focal or global CNS dysfunction
Encephalitis - Epidemiology
overall incidence of hospitalization was 7.3 cases/100,000 annually
Children < 1 yo - 13.7 cases/100,000 per yr
Adults >65 yo - 10.6 cases/100,000 per yr
Clinical presentation
Fever HeadacheAltered mental status Focal neurologic signs spectrum of clinical evolution during
encephalitis varies widely
Encephalitis
CT scan – nml at the onset of encephalitis.MRI – much more sensitive for acute
changes
EEG - helpful adjunct +/- localize the region of encephalitic involvement considerably more sensitive
Management
Appropriate antiviral, antimicrobial or antifungal therapies
Intravenous immune globulin, corticosteroids, or other immune system modulators.
Herpes Simplex Virus Encephalitis
Most common encephalitis diagnosedFeverPersonality changeAutonomic dysfunctionDysphagiaSeizuresHeadacheAltered level of consciousness
HSV
Mildly elevated CSF WBC counts (lymphocyte predominant) and CSF protein
CT and MRI studies - normal if obtained early in the course of illness Unilateral or bilateral temporal lobe involvement (most common
finding)
Diagnostic test - HSV DNA detection by PCR on the CSF both highly sensitive and specific If initial result negative, test should be repeated on a second
CSF specimen.
Treatment
IV acyclovir 10 mg/kg per dose every 8 hours for 2 to 3 weeks.
Better outcomes if: age < 30 yo shorter duration of symptoms before initiation of
treatment GCS >10 at the time of presentation.
Investigations
CT headLPCBC, Blood cultureLytesGlucoseESR, CRP
Back to our patient
Question #3
For a patient who is suspected of having acute encephalitis, which of the following studies is most likely tobe helpful?
A. Cerebrospinal fluid glucose level.B. Computed tomography scan.C. Electroencephalography.D. Magnetic resonance imaging.E. Viral culture
Any Questions?
References
C Waruiru and R Appleton Febrile seizures: an update Arch Dis Child. 2004 August; 89(8): 751–756.
Jones T. Jacobsen SJ. Childhood febrile seizures: overview and implications International Journal of Medical Sciences. 4(2):110-4, 2007.
Baumann RJ. Duffner PK. Treatment of children with simple febrile seizures: the AAP practice parameter. American Academy of Pediatrics. Pediatric Neurology. 23(1):11-7, 2000 Jul.
AAP Practice Parameter: Long Term Treatment of the Child With Simple Febrile Seizure Pediatrics. 103(6) June 1999
References
Appleton R. Choonara I. Martland T. Phillips B. Scott R. Whitehouse W. The treatment of convulsive status epilepticus in children. Archives of Disease in Childhood. 83(5):415-9, 2000 Nov.
Riviello JJ Jr. Ashwal S. Hirtz D. Glauser T. Ballaban-Gil K. Kelley K. Morton LD. Phillips S. Sloan E. Shinnar S. American Academy of Neurology Subcommittee. Practice Committee of the Child Neurology Society. Practice parameter: diagnostic assessment of the child with status epilepticus Neurology. 67(9):1542-50, 2006 Nov 14.