Ch 88-Seizures Flashcards
What percent of adults experience at least 1 seizure? what percent will be diagnosed with epilepsy?
seizure- 10%
epilepsy- 3%
Define Seizure
A seizure is a sudden change in behavior caused by electrical hypersynchronization of neuronal networks in the cerebral cortex. (UTD)
Seizures are excessive excitatory neuronal activity associated with hypersynchrony of neighboring cells, resulting in sensory, motor, autonomic, or cognitive function alterations (Rosens 10th edition)
Define convulsions
refers specifically to the motor manifestations of a seizure
Define ictal period and post ictal period
The ictal period is the time
during which a seizure or seizure-like
activity occurs.
A postictal period
is an interval of transient neurologic dysfunction (commonly AMS or weakness) immediately following a seizure, generally lasting < 1 hour.
Longer ictal activity is associated with more
prominent and prolonged postictal symptoms
How are seizures classified?
- Primary seizure- unprovoked vs Acute symptomatic seizure - provoked (secondary)
- Generalized vs focal vs unknown onset
- Convulsive vs non-convulsive
Define status epilepticus
> 5 min of continuous seizures
2 discrete seizures with incomplete recovery between seizures
convulsive vs non-convulsive (dx on eeg)
Define epilepsy
The International League Against Epilepsy defines epilepsy as a
(A) diagnosis of epilepsy syndrome (e.g., juvenile myoclonic epilepsy, Lennox-Gastault
syndrome, benign rolandic epilepsy, infantile spasms);
(B) two or more seizures occurring more than 24 hours apart without an identified trigger;
(C) one unprovoked seizure coupled with
a higher likelihood of recurrent seizures over the subsequent decade
Define Primary vs secondary seizures
Primary- unprovoked
Secondary- provoked (acute symptomatic seizure caused by underlying pathophysiologic process
Define generalized vs focal seizures
Generalized- abnormal neuronal activity in both hemispheres (LOC or aLOC)
Focal Seizures-occur in one hemisphere>patient maintains consciousness
How are generalized seizures categorized?
Motor
-tonic clonic
-myoclonic
-atonic
-tonic
-clonic
-myoclonic-tonic-clonic
-myoclonic-atonic
-epileptic spasms
Non-motor (absence)
-typical
-atypical
-myoclonic
-eyelid myoclonia
How are focal seizures classified
Aware vs impaired awareness
Motor onset:
-autospasms
-atonic
-clonic
-epileptic spasms
-hyperkinetic
-myoclonic
-tonic
non-motor onset
-autonomic
-behaviour arrest
-cognitive
-emotional
-sensory
Triggers of breakthrough seizures in epilepsy
sleep deprivation
emotional or physical stress
menses
illness
medication change or non compliance
**still considered unprovoked
Most common cause of SE and new epilepsy in the elderly?
cerebrovascular disease
Define NORSE
new onset refractory status epilepticus
Pts without a known diagnosis of epilepsy or clear triggers (absent toxic exposure, metabolic derangements, or structural brain injury) presenting with denovo refractory status epilepticus
Define FIRES
subcategory of NORSE to specify subset of patients with clear prodrome of febrile illness for 24hr up to 2 weeks prior to SE presentation
FIRES is common (but not exclusive to) pediatric population
List 10 causes of seizures and status epilepticus in adults (Rosens Box 88.1)
Box 88.1
- Autoimmune
-AI encephalitis
-CREST, Goodpasture syndrome, SLE
-MS
-TTP
-Acute disseminated encephalomyelitis (AEDM) - Cerebrovascular disease
-CVA
-AVMs
-CVST
-ICH
-SAH
-PRES
-RCVS - Dementias
- alzheimers
-fronto-temporal dementia
-vascular dementia - Genetic syndromes & structural abnormalities
- Focal cortical dysplasia
-hydrocephalus
-metabolic disease
-mitochondrial disease
-Porphyria
-Tuberous scelrosis complex
-wilsons disease - Hypoxic ischemic brain injury
- Intracranial tumour
-gangliogliomas
-gliomas
-lymphoma
-meningioma
-metastases
-neuroectodermal tumor - Metabolic
- acidosis
-elevated BUN
-hypo/hyperglycemia
-hyperammonia
-hyper/hyponatremia
-hypocalcemia
-hypomagnesemia
-wernicke encephalopathy - Medications
-EtOH and WD
-alkylating agents
-baclofen toxicity and WD
-benzo WD
-CAR-T
-Carbapenums
-cephalosporins (cefipime)
-cylosporins
-digoxin
-fentanyl
-heavy metals
-lidocaine
-metronidazole
-tramadol
-tacrolimus
-subtherpeutic anti seizure meds - Systemic disease
-AoC renal failure
-cirrhosis - Trauma
subdural/ epidural hematoma
-SAH
-DAI
Define ictal asystole
syndrome of focal epilepsies with left temporal onset, in females with PMHx of heart condition
ictal asystole lasting longer than 30 seconds is associated with
extra-temporal
seizure focus and secondary generalized tonic-clonic
seizures.
Most common cause for ED presentation of recurrent seizures
medication non compliance
List common causes of adult onset focal seizures in low and middle countries
- neurocysticerosis
- malaria
List 10 potential systemic complications related to seizures and status epilepticus
- Cardiac
- arrhythmia’s
- cardiac arrest
- CM
- HTN
- thermodysregulation - MSK
-fracture/dislocation - GI
-hepatotoxicity and pancreatitis
-ilieus and bowel ischemia - Heme
- rhabdo
-leukocytosis/leukopenia
-thrombocytopenia - Pulmonary
-AW obstruction
-apnea/hypoventilation
-aspiration
-hypoxia
-mucous plugging
-pulmonary edema - Renal/acid-base
- ARF
-Acidosis -lactic, respiratory
-Hyperglycemia
-hyperkalemia
-myoglobinuria - Prolonged ICU course complications
How to manage seizure caused by hyponatremia
Hypertonic saline (3%)
adult- 100 ml 3% NaCl / 10 min
children- 2-5ml/kg (up to 150 ml) over 20 min
How to manage seizures caused by hypocalcemia
calcium chloride or gluconate amps until seizure aborts
How to manage seizures caused by TCA OD
sodium bicarb
1 to 2 mEq/kg IV bolus; repeat as needed to maintain ECG QRS complex ≤ 100 msec
How t manage seizures caused by salicylate OD
Sodium bicarb or HD
Administer 1 to 2 mEq/kg IV bolus; repeat as needed to maintain a blood pH of 7.4 to 7.5
How to manage seizures caused by isoniazid toxicity
Pyridoxine 5 g IV (adult) or 70 mg/kg (pediatric)
How to manage seizures caused by lithium toxicity
HD
How to treat seizures caused by sympathomemetics/EtOH WD/ MDMA
Benzodiazepines
How to treat seizures caused by eclampsia
Magnesium sulfate IV loading dose of 4 to 6 g over 15 to 20 minutes, then 1 to 2 g/h infusion; monitor patients for
hyporeflexia; alternatively, lorazepam (Ativan) 4 mg IV over 2 to 5 minutes or diazepam (Valium) 5 to
10 mg IV slowly can be used to terminate the seizure, after which magnesium sulfate is administered
Seizure + HTN+ bradycardia are suggestive of what intracranial pathology
herniation syndromes
What are proposed seizure triggering thresholds for the following metabolic derangements: Glucose, sodium, calcium, magnesium, BUN, creatinine
Glc <2.0 or >25
Na <115
Ca <1.2
Mg <0.3
BUN >35.7
creatinine >884
When do early post traumatic seizures typically occur? how many of those occur in the first 24h
Early post-traumatic
seizures occur
within the first week, with over 50% occurring within the first 24 hours
Describe post traumatic seizure prophylaxis
Early post-traumatic
seizures occur
within the first week of initial brain insult, with over 50% occurring within the first 24 hours.
Guidelines recommend 7 days in traumatic brain injury and short-term
therapy in subarachnoid hemorrhage.
How are seizures in pregnancy classified
- Diagnosed epilepsy + pregnant
- new onset seizure in pregnant pts
- seizure 2/2 to eclampsia
Define recruitment as it relates to seizure development and progression
Defined as the activation of neurons by increased electrical activity of adjacent
neurons.
Neuronl impulses that track into deep circuits of the subcortex (ie RAS) or cross the midline cause alterations in LOC.
The process of recruitment explains seizure auras (i.e., alterations in sensation, autonomic deregulations, aphasia, deja vu, lip smacking,
repeated swallowing, picking at clothing secondary to abnormal neuronal activity) and how focal seizures can secondarily become generalized
List 4 clinical findings that differentiate seizures from syncope
Features of Seizure:
1. Post ictal state
2. Longer duration of motor manifestations
3. loss of bladder/bowel control
4. tongue biting or laceration
Features of syncope
1. rapid recovery/ spontaneous return of conciousness
2. less likely to have motor involvement, if present lasts seconds
3. no loss of bladder/bowel function
4. No tongue biting
List 5 features that differentiate neurogenic and psychogenic seizures
Features of PNES
- often longer in duration compared to neurogenic
-recollection of events during psychogenic seizure
- forward thrusting pelvic movements
-head turning from side to side during event
-gaze deviation away from examiner during event
-avoid noxious stimuli during event
-typical metabolic acidosis not present after event
List 5 diagnosis that can mimic seizures
Cardiac
1. Vasodepressive (vagal) syncope
2. Orthostatic syncope
3. Cardiogenic syncope
Neurologic
1. Stroke, transient ischemic attack
2. Atypical migraine
3. Movement disorders
4. Mass lesions
Toxicologic
1. Intoxication, inebriation
2. Oversedation, over-analgesia
- Extrapyramidal symptoms
Metabolic - Hypo-, hyperglycemia
- Thyrotoxicosis
- Delirium tremens
Infectious
1. CNS infections
2. Tetanus
Psychiatric
1. Pseudoseizure
2. Panic attacks
3. Cataplexy
List 10 causes of status epilepticus in adults (crack cast)
Metabolic Disturbances
1. Hepatic encephalopathy
2. Hypocalcemia
3. Hypoglycemia or hyperglycemia
4. Hyponatremia
5. Uremia
Infectious Processes
1. Central nervous system abscess
2. Encephalitis
3. Meningitis
Withdrawal Syndromes
1. Alcohol
2. Antiepileptic drugs
3. Baclofen
4. Barbiturates
5. Benzodiazepines
Central Nervous System Lesions
1. Acute hydrocephalus
2. Anoxic or hypoxic insult
3. Arteriovenous malformations
4. Brain metastases
5. Cerebrovascular accident
6. Eclampsia
7. Head trauma: acute and remote
8. Intracerebral hemorrhage
9. Neoplasm
10. PRES
Intoxication
1. Bupropion
2. Camphor
3. Clozapine
4. Cyclosporine
5. Flumazenil
6. Fluoroquinolones
7. Imipenem
8. Isoniazid
9. Lead
10. Lidocaine
11. Lithium
12. MDMA
13. Metronidazole
14. Synthetic cannabinoids
15. Theophylline
16. Tricyclic antidepressants
Outline the management of SE in the pre hospital setting
Assess ABCs
Attach monitors -Pulse oximetry
ECG
BG- treat if low
Place pt in position of safety (left lateral decubitus)
Give one of the following medications:
- Midazolam 10 mg IV/IM/IN - FIRST LINE IF NO IV
- Lorazepam 2 mg up to max of 10 mg IV - FIRST LINE IF IV
- Diazepam 5 mg up to max of 20 mg PR - do not use re: poor absorption
Outline the management of SE in the ED
- Ongoing seizure activity:
-Midazolam 10 mg IV/IM/IN - FIRST LINE IF NO IV
- Lorazepam 2 mg up to max of 10 mg IV - FIRST LINE IF IV
AND (Keppra first line)
- Phenytoin 20 mg/kg IV at max rate 50 mg/min
- Fosphenytoin 20 PE/kg IM or IV at max rate of 150 mg/min
- Valproic Acid 20-40 mg/kg at 3-6 mg/kg/min
- Keppra 1000-3000 mg over 15 minutes
If seizure still not aborted
- Intubation and EEG recommended
- Treat with one of the following third-line medications:
- Phenobarbitol 20 mg/kg IV at 50-75 mg/min
- Midazolam 0.2mg/kg IV, then 0.1-0.4 mg/kg/hr
- Propofol 2 mg/kg IV at 2-5 mg/kg/hr, then 5-10 mg/kg/hr as
needed
Diazepam dosing for seizure in adult and peds
Adult 5 mg IV, up to max 20 mg or 10-20 mg PRN
Peds 0.2-0.5 mg/kg IV/ET
or 0.5-1.0 mg/kg PR
(max 20 mg)
May repeat in 10
minutes; monitor
respiratory status
Lorazepam dosing for seizure in adult and peds
Adult- 2 mg IV at 2 mg/min,
up to max 10 mg IV
Peds- 0.05-0.1 mg/kg IV
(max 2 mg)
Preferred IV benzo;
may repeat in 10
minutes; monitor
respiratory status
Midazolam dosing for seizure in adult and peds
Adult- 5 mg, up to a max of
10 mg IV/IM/IN
Peds-0.2 mg/kg IV/IM/IN
(max 5 mg)
Preferred IM
benzodiazepine; may
repeat in 10 minutes;
monitor respiratory
status
List 10 indications for CT head for first seizure
- New focal deficit
- Persistent altered mental status
- Fever
- Recent trauma
- Persistent headache
- History of cancer
- Anticoagulant use
- Suspicion or known history of AIDS
- Age > 40 years
- Presence of partial complex seizure
List 5 characteristics of ictal events
- Abrupt onset:
-History should focus on any evidence of an aura. - Brief duration.
-Seizures rarely last longer than 90 to 120 seconds, Status epilepticus is the important exception. - Alteration of consciousness.
-Generalized seizures are manifest by loss of
consciousness; focal seizures are often accompanied by an alteration in consciousness. - Purposeless activity. -Automatisms and undirected tonic-clonic movements are common
in ictal events. Tonic-clonic movements are rhythmic and generally do not involve head shaking. - Postictal state.
-can last from minutes to hours, depending on
which specific region of the brain triggered the seizure, seizure duration, age, and use of an antiepileptic drug (AED).
Name 3 metabolic causes of seizures
The top 6 metabolic abnormalities causing seizures are:
- Hyponatremia
- Hypocalcemia
- Hypoglycemia
- Hyperglycemia
- Uremia
- Hyperammonemia
What percentage of patients with convulsive status epilepticus will
develop non-convulsive status epilepticus?
up to 15% of patients who are successfully treated for convulsive status
epilepticus remain in non-convulsive status afterwards.
List 5 causes of persistent AMS in a patient who has seized
Metabolic- hypoglycaemic; encephalopathy
CNS- ICH, migraine, Transient global amnesia
Infectious
Drug intoxication or WD
Psychogenic
What is Todds Paralysis?
- Transient post-ictal paralysis
- Common (13%) following focal motor seizure affecting one side of the body
- Can also affect speech, gaze or vision
- Usually subsides within 24hrs
**high likelihood of underlying structural cause of seizure
List 4 features that increase the likelihood the event was a seizure
> 45 yo
Abrupt onset and brief duration
Confirmed unresponsiveness
Postictal confusion
Rhythmic limb shaking or dystonic posturing
Tongue biting
Head or eye turning to one side
Cyanosis
Preceding déjà vu or aura
NOTE
Incontinence and trauma were not discriminative findings between seizure, syncope, and nonepileptic attack disorder..
List 8 causes of toxin-induced seizure
- organophosphate
- TCA
- Salicylate
- sympathomemetic
- Camphor
- Methylxanthine
- Benzo WD
- EtOH WD
- lithium
- lidocaine
Name 5 infectious causes of provoked seizures
Bacterial meningitis (s. pneumonia most common in adults, GBS in <2mo
Viral encephalitis (HSV, EBV, enterovirus, west nile)
Abscess (gram + strep and staph most common)
syphillis
cysticercosis
Malaria
List 5 causes of seizure with immediate reversible treatment
Hyponatremia
Hypoglycemia
Hypocalcemia
TCA
ASA
Isoniazide
cocaine
etoh
lithium
MDMA
eclampsia
List 3 causes of seizure in HIV patients
- Toxoplasmosis
Clinical: Fever; HA; AMS; seizures; weeks
Imaging: ring enhancing
Dx: PCR for Toxo - Cryptococcous
Clinical:Fever; HA; AMS; seizures
Imaging: ring enhancing
Dx: india ink - CNS lymphoma
Clinical: fever; wt loss; sweats; months
Imaging: ring enhancing
Dx: PCR for EBV - PML
Clinical: FND; ataxia; VF loss; months
Imaging: demyelinatoin
Dx: PCT for JC - HIV encephalopathy
Clinical: depression, movement, memory
Imaging: T2 signals
Dx: PCR for HIV - CMV
Clinical: FND; confusion
Imaging: micronodules
Dx: PCR for CMV - Abscess
Clinical: Fever; FND; bacteremia
Imaging: ring enhancing
Dx: culture - TB
Clinical: FND; TB SxS
Imaging: Ring enhancing
Dx: Culture
Phenytoin dosing
Phenytoin 20 mg/kg IV at max rate 50 mg/min
Fosphenytoin dosing
Fosphenytoin 20 PE/kg IM or IV at max rate of 150 mg/min
Valproic Acid dosing
Valproic Acid 20-40 mg/kg at 3-6 mg/kg/min
Keppra dosing
Keppra 1000-3000 mg over 15 minutes
phenobarbitol dosing
Phenobarbitol 20 mg/kg IV at 50-75 mg/min
Midazolam infusion dosing for third line therapay
Midazolam 0.2mg/kg IV, then 0.1-0.4 mg/kg/hr
Propofol infusion dose 93rd line)
Propofol 2 mg/kg IV at 2-5 mg/kg/hr, then 5-10 mg/kg/hr as
needed
Carbamezipine loading dose and route of administration of AEDs when resuming in the ED
8mg/kg po suspension x1
Keppra loading dose and route of administration of AEDs when resuming in the ED
1500 mg po load or rapid IV up to 60 mg/kg
phenytoin loading dose and route of administration of AEDs when resuming in the ED
20 mg/kg divided into max doses of 400 mg q 2 h po.
or
18 mg/kg IV at <50 mg/min
VPA loading dose and route of administration of AEDs when resuming in the ED
up to 30 mg/kg IV to max rate of 10 mg/kg/min
What anticonvulsants can paradoxically cause seizures in supratherapeutic levels?
Phenytoin
Carbamazepine
Valproic Acid
Lamotrigine
Therefore… if known to take Rx, give HALF loading dose (in case they are seizing because of supratherapeutic levels)
What options do you have for anti-epileptics if you can’t get IV access?
Midazolam IM, IN, Buccal
Lorazepam SL (can also give IM)
Diazepam PR
When would you consider starting a patient with first time seizure on an antiepileptic?What DC instructions will you provide
Decision to start on anticonvulsant based on:
Risk of seizure recurrence – more common in partial seizures, status, hx, intracranial sx/trauma, presence of Todd’s paralysis
Presence of any underlying predisposing disease – particularly HIV
Have to consider risk of anticonvulsant tx – side effects and drug interactions
In most cases, no need to tx after 1st unprovoked seizure
Refer to neuro – let them decide
PATIENT EDUCATION MOST IMPORTANT!
d/c instructions: avoid swimming w/o lifeguard, don’t work w/ hazardous tools/equipment/ladders, report to driving agencies as required, document instructions precisely
