Approach to
the patient with…
PROLONGED
SEIZURE / STATUS EPILEPTICUS
Definition of status
epilepticus
- definitions may vary
- continuous seizure lasting
greater than 30 minutes or recurrent seizures without complete recovery of
consciousness between attacks
- start treatment if continuous
seizures for greater than 5 minutes
Epidemiology
- 5-10,000 cases per year in
Canada
- most common at extremes of
age
Classification of status epilepticus
Convulsive
- generalized (most commonly
seen, management discussed below)
- partial (simple or complex)
- epilepsy partialis
continua = unilateral, simple partial/focal clonic status
Non-convulsive
- generalized (e.g. absence)
- partial (simple or complex)
Complications of prolonged
status epilepticus
Early
- hypertension, hyperthermia
- hyperglycemia, hyperkalemia,
peripheral leukocytosis (up to 20), CSF leukocystosis (up to 80 cells)
- tongue bite, aspiration,
posterior shoulder dislocation, fractures
Late (>30-60 minutes to
days)
- hypotension, hyperthermia
- normo- / hypo-glycemia,
hyperkalemia, leukocytosis
- cerebral edema
- ischemic damage to
hippocampus, thalamus, neocortex, cerebellum
- rhabdomyolysis / acute renal
failure
- neurogenic pulmonary edema
- arrythmias, high output heart
failure
- death
Mortality
- 20% overall
- increases with increasing age
- also depends on whether
etiology is acute (higher mortality, poor response to therapy ) vs. chronic
(lower mortality, better response to therapy), see below
- myoclonic status with global
ischemia / anoxia is usually a preterminal event
Etiology
Acute / New Onset Seizures:
metabolic (hypoglycemia,
electrolyte abnormality, organ failure), sepsis, CNS infection, head
injury, drugs/toxins (alcohol intoxication/withdrawal, cocaine,
amphetamines, benzodiazepine withdrawal, TCA overdose, antibiotics),
hypoxia/anoxia, stroke, intracranial mass lesion
Chronic / Pre-Existing Seizure
Disorder:
preexisting epilepsy /
breakthrough seizure, low [anti-epileptic medication] / non-compliance / change
in medicatons / crossover period, drugs / toxins (as above), remote CNS process
(tumor / stroke), Rasmussen's (kids/teens)
Children (<16 years old)
fever / infection > medication
change > metabolic
Adults (>16 years old)
cerebrovascular > medication
change > EtOH- / drug-related > anoxia
DDx
movement disorder,
pseudoseizure
Management
1. ABCs
- vitals (including BP, pulse,
temp., RR), oxygen saturation
- cap gas, finger prick glucose
- establish IV, cardiac monitor
- 100% oxygen (mask or nasal
prong), consider nasal airway, +/- intubation
2. 100 mg thiamine IV FOLLOWED
by 50cc 50% D5W if glucose low
3. a. blood work: CBC, lytes,
Ca/Mg/P, urea, creatinine, LFTs & enzymes, glucose, tox. screen, [AEDs], if
appropriate
b. quickly review past medical
history for potential contributory factors
4. Administer anticonvulsive
medication
a. BENZODIAZEPINES
- lorazepam / ativan 2-4 mg
over 1-2 min IV (max. 0.1 mg/kg) OR
- diazepam / valium 5-10 mg
over 1-2 min IV (max. 0.2-0.4 mg/kg) or PR 0.5mg/kg (max. 20 mg)
***MONITOR respiratory status
and for hypotension
NOTE:
- both are equally effective
but lorazepam's effect is longer lasting (hours) vs. diazepam (30 min)
- most seizures will stop with
benzodiazepine treatment alone (~70%)
- need to load with dilantin
for long term effect because benzos will wears off
b. DILANTIN / PHENYTOIN
- 1-1.5g IV (15-18 mg/kg) @
20-30 mg/min (max 50 mg/min)
(NB: Usual "LOADING DOSE" of 1 g is usually
NOT adequate!)
*** MONITOR for hypotension and
heart block (frequency increases with increasing infusion rate)
- If seizures have stopped, use
slower rate, if seizures ongoing use higher rate.
If patient is still seizing…
c. Consider giving additional
DILANTIN
- 5-10 mg/kg IV @ 20-30 mg/min
up to max total dose of 30 mg/kg
If pt. is still seizing after
> 45 min. contact ICU. Should be ready to intubate if considering phenobarbital
d. PHENOBARBITAL
- 20 mg/kg @ 50 mg/min IV
- Respiratory and BP support
and cardiac monitoring must be available
If patient is still seizing…
e. MORE PHENOBARBITAL
- 5-10 mg/kg up to max dose of
30 mg/kg
If patient has been seizing
>60-90 min…
f. ANAESTHESIA
- REQUIRES intubation and
ventilation, central and arterial line monitoring and continuous EEG
Options:
1. midazolam 0.2 mg/kg SLOW IV
bolus then 0.75-10 mcg/kg/min
2. propofol 1-2 mg/kg IV then
2-10 mg/kg/h
*** titrate to EEG ie. goal is suppression
of spikes
- use IV fluids and dopamine to
treat hypotension
- taper infusion at 12 h,
monitor with EEG
5. DON'T FORGET to determine
and treat, if possible, the underlying cause!
Related Topics
- refractory status epilepticus
References:
UpToDate
Neurologic Clinics 19:347 '01
NEJM 338:970 '98
Last update: November 2002
Reviewed by: Pending review
Neurological Medicine Pocketbook
© 2002-2004 UWO Neurology Residents
http://www.uwo.ca/cns/resident
All Rights Reserved