Cluster Seizures, Status Epileptic, Emergency Management

Question 1

define cluster seizures

Answer 1

2 or more seizures within 24 hours

Question 2

define status epilepticus

Answer 2

greater than 5 minutes of a continuous seizure
-focal or generalized

2 or more generalized seizures in which the patient does not return to normal mentation

Question 3

describe cluster seizure therapy

Answer 3

1. not very different than managing patients with isolated seizures

-maintenance therapy: phenobarb alone or in conjunction with potassium bromide

-at home therapies to prevent further clusters

Question 4

describe goals of cluster seizure treatment

Answer 4

1. keep patient from having to come to hospital
2. decrease number of clusters
3. decrease number and severity of seizures per cluster
4. increase the time between cluster events

Question 5

describe step 1 and 2 of cluster management

Answer 5

1. maintenance therapy
   -increase interictal time (seizure less frequently)
   -phenobarb and/or potassium bromide
2. treat the cluster event: reduce number of seizures per cluster
   -benodiazepams: midazolam, diazepam, clorazepate
   –route: oral, rectal, or intranasal
   –short duration of action (30 min)
   –first pass metabolism:
   —orally: liver grabs it
   —rectally: liver doesn’t grab it first!
   -pulse therapy: levetiracetam

Question 6

describe diazepam (valium)

Answer 6

1. high lipid solubility: crosses BBB quickly
2. high first pass metabolism (sad)
3. not given orally
   -first pass
   -in cats: oral = fulminant hepatic necrosis (BAD!!)
4. given IV (not IM bc muscle necrosis)
5. give per rectum:
   -may reach anticonvulsant concentration in as short as 8 min, peak concentration 15-30 min
   -goal is not to stop the first seizure in a cluster, it’s to stop the second one
6. downsides:
   -light sensitive
   -binds to plastic (can’t predraw up for owners)
   -requires “drawing up”
   -controlled drug

Question 7

describe midazolam

Answer 7

1. high water solubility
2. hight first pass metabolism (sad)
3. given IV, IM, IN
   -with IN can use an atomizer to convert the drop to a mist for easier admin
4. downsides:
   -longer to reach peak the diazepam
   -requires “drawing up”
   -controlled drug
   -short half life - frequent redosing
5. good:
   -not light sensitive
   -no issue with plastic binding

Question 8

describe levetiracetam as pulse therapy

Answer 8

decreases seizures, severity, and cluster events! can use during the cluster to resolve the cluster (decrease) the number of events per cluster

Question 9

describe status epilepticus

Answer 9

1. prolonged seizure (>5min)
2. recurrent seizures with incomplete recovery
3. long term systemic side effects
   -permanent neuronal injury/death
   -SYSTEMIC side effects!!
   -mortality 25-40%

Question 10

describe the systemic effects of status epilepticus

Answer 10

phase 1 (compensated): systemic effects due to catecholamines/stress response
-hyperthermia
-hyperglycemia
-hypertension
-tachycardia
-strong pulse quality

phase 2: uncompensated, due to failure of compensatory responses
-hypothermia
-hypoglycemia
-hypotension
-tachycardia/tachypnea
-hypoxemia
-poor pulse quality: decline in cardiac output
-azotemia

all result in:
-metabolic acidosis
-cardiac arrhythmias
-noncardiogenic edema!!
-rhabodmyolysis (CK, ALT, AST)
-acute kidney injury (acute tubular necrosis)

Question 11

describe the stages of status epilepticus and how to treat in each stage

Answer 11

stage 1: impending
-first-line treatment likely responsive
-midazolam/diazepam
–midazolam bolus usually stops; if not, double the dose and try again
–after 3 boluses, start CRI and if not working switch drugs
-at the same time as IV midazolam, also start phenobarb maintenance (IV)

stage 2: established
-first-line treatments progressively less responsive
-second-line treatment likely responsive

if still not responsive, ketamine is what you add next (3rd line)

if still not responsive, then add pentobarbital. propofol, etc., intubate, and figure out how to get it to an ER clinic for monitoring

Question 12

describe emergency management of cluster seizures

Answer 12

first choice:
benzodiazepines: good for
1. rapid cluster (seizures every 20 min or hour)
2. doesn’t recover between seizures
3. seizures lasting >2-3 min

options:
1. intranasal midazolam! first choice
-use atomizer for easier admin, 70% effective
2. rectal diazepam: only about 20% effective

also oral pulse therapy
-minimal evidence but common practice, not needed for first-time cluster since maintenance meds should work

1. levetiracetam: 60mg/kg q8 for 48 hr
2. clorazepate:
   -no evidence but very safe