Neurology Flashcards
What blood work needs to be checked in a patient with status epilepticus?
BMP, GLUCOSE, calcium, magnesium, phosphorus, LFTs, TOXICOLOGY, ASD levels
In status epilepticus, what should be administered BEFORE (or along with) any drugs?
Glucose and thiamine (100mg IV)
What is the first line drug for Status epilepticus?
Dosing?
Benzos are first line!
Ativan (lorazepam): 4mg IV OR 0.1mg/kg IV given at a max rate of 2mg/min and assess for a few minutes to see if additional benzos are needed.
There is no definite max dose of lorazepam but monitor BP
If no Ativan available, can give Valium up to 10mg IV
What are the second line drugs used for status epilepticus?
Dosing?
Fosphenytoin: 20mg/kg phenytoin equivalents (or phenytoin 20mg/kg) infused at 100-150 PE/min (20-50 for phenytoin)
Valproate: 30mg/kg loading dose and infused at 10mg/kg/min
Keppra: 60mg/kg (max dose 4500mg) infused over 15 min
What are concerns about phenytoin administration? How is fosphenytoin different?
Propylene glycol is required to solubilize phenytoin so there tend to be great risk of cardiovascular effects like arrhythmias and hypotension (although studies show those risks persist for fosphenytoin as well), but this also makes phenytoin more likely to precipitate out: cannot be given in the same IV as benzos or any glucose/dextrose solution
Phenytoin has higher risk of venous thrombosis, purple hand syndrome
Fosphenytoin is a prodrug of phenytoin and is highly water soluble
Should not give in cases of seizures caused by cocaine or other local anesthetics- can INTENSIFY these seizures
What are the risks with valproate?
Benefits?
Benefits: no sig cardiovascular effects
Toxicity: can cause hepatic dysfunction and coagulopathy- not ideal drug in patients w liver disease or active bleeding issues
How do you treat refractory status epilepticus?
- Repeat fosphenytoin at 5mg/kg PE or any of the other first line drugs not given (ie ASD keppra or valproate)
- intubate
- continuous BP, EKG monitoring
- continuous EEG monitoring
- then:
1. Continuous midazolam infusion: bolts with 0.2mg/kg at 2mg/min followed by 0.1mg/kg/hr titrating up to 3mg/kg/hr
2. Propofol infusion: loading dose of 1-2mg/kg and titrate up to 10-12mg/kg/hr (ideally for less than 48hr)
3. Pentobarbital initial dose 5mg/kg over 10 min- repeat as necessary until seizures stop. Then 1-5mg/kg/hr
2nd line meds should be maintained for 24 hours after seizure freedom is achieved
MONITOR LEVELS OF PHENYTOIN
What are second line antiseizure agents for status epilepticus?
- Phenobarbital: 20mg/kg at 30-50mg/min
Must monitor cardiac and respiratory status
Half life is 87-100 hours!!!! Risk of prolonged sedation is highest w this drug - Lacosamide (vimpat): 200-400mg IV bonus
Rare side effects of second degree and complete AV block - need to monitor for PR prolongation
EKG should be done prior to admin of this drug and avoid use in patients w heart disease or concurrent use of PR prolonging drugs
What is propofol infusion syndrome?
Rare complication
Associated w higher doses (>4mg/kg/hr) and prolonged use (48hr)
Risk factors: young age, concurrent steroid use
Symptoms: acute refractory bradycardia, severe metabolic acidosis, cardiovascular collapse, rhabdomyolysis, hyperlipidemia, renal failure, hepatomegaly
Treatment: dc propofol and supportive care
Characteristics of tumefactive demyelination on MRI
Open ring contrast enhancement- incomplete portion is on the grey matter side of the lesion (Sagittal and coronal views are best)
LOW rCBV perfusion imaging
Increase in ADC but no restricted diffusion
How to diagnose MS?
Lumbar puncture: oligoclonal bands- mild elevation in white blood cells (15 or less), protein elevation (most less than 50 but nearly all less than 100)
Treatment for MS in acute attack?
If there is objective evidence of neurologic impairment or painful paresthesias:
1. 3-7 days of IV methylprednisolone (1000mg per day) with or without a prednisone taper
Or oral prednisone 1000mg daily
Treatment for refractory MS:
1. Plasma exchange - every other day for 2 weeks
What is the initial disease modifying treatment for MS?
Options:
- High efficacy
- Low risk
Options:
IV natalizumab- risk PML!! AntiJC virus antibodies
Oral tecfidera
Absolute contraindications for tPA administration?
Current ICH
Prior ICH (microbleeds on MRI do not count)
Severe uncontrolled HTN: SBP > 180, DBP > 110 (if severely hypertensive need to treat prior to tPA)
Serious head trauma or previous stroke in the last 3 months
Thrombocytopenia (<100,000)
Coagulopathy (INR >1.7 or PTT > 15)
Anticoagulant use: therapeutic lovenox, direct thrombin inhibitors (dabigatran, argatroban), factor Xa inhibitors
Severe hypo or hyperglycemia
Frank infarction on CT
Relative contraindications for tPA?
Advanced age (>75)
Mild or improving symptoms (NIHSS < 4)- current guidelines say may be considered
Severe stroke (NIHSS 20-25) and coma
“Recent major surgery”: 14 days -3 months
Recent puncture of a noncompressible vessel (within 7 days)
Recent GI or GU hemorrhage (21 days)
Seizure at onset of stroke symptoms
MI within 3 months
CNS structural lesions (tumor, AVM, aneurysm)
Dementia (this is literal nonsense)
