Status epilepticus: Difference between revisions
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==Background== | ==Background== | ||
===Definition=== | ===Definition=== | ||
*Seizures are abnormal neuronal activity with various neurological sequale. | *Seizures are abnormal neuronal activity with various neurological sequale. | ||
**Further defined by whether they involve 1 hemisphere (partial) or both hemispheres (generalized). While generalized seizures surely cause an alteration in mental status, seizures involving one hemisphere (partial) may further be subdivided by whether they maintain baseline mental status (simple) or an alteration (complex). | **Further defined by whether they involve 1 hemisphere (partial) or both hemispheres (generalized). While generalized seizures surely cause an alteration in mental status, seizures involving one hemisphere (partial) may further be subdivided by whether they maintain baseline mental status (simple) or an alteration (complex). |
Revision as of 10:49, 25 August 2015
Background
Definition
- Seizures are abnormal neuronal activity with various neurological sequale.
- Further defined by whether they involve 1 hemisphere (partial) or both hemispheres (generalized). While generalized seizures surely cause an alteration in mental status, seizures involving one hemisphere (partial) may further be subdivided by whether they maintain baseline mental status (simple) or an alteration (complex).
- Epilepsy is defined a 2 or more epileptic seizures that occur unprovoked by any identifiable cause. This include all seizure events with the exception of febrile or neonatal seizures.
- Further subclassified into cryptogenic (meaning unknown cause) or symptomatic (meaning associated with previous CNS insult).
- Symptomatic seizures further subdefined as acute or remote (depending on if > or < 1 week after CNS insult)
- Further subclassified into cryptogenic (meaning unknown cause) or symptomatic (meaning associated with previous CNS insult).
- Seizure type and associated EEG findings are at core of determining risk of recurrence and indication for antiepileptic therapy. Follow the “seizure” link (pending Jan 2014) for more information on the non-acute general treatment of seizures.
Clinical Features
Differential Diagnosis
Seizure
- Epileptic seizure
- First-time seizure
- Seizure with known seizure disorder
- Status epilepticus
- Temporal lobe epilepsy
- Non-compliance with anti-epileptic medications
- Hyponatremia
- INH toxicity
- Non-epileptic seizure
- Meningitis
- Encephalitis
- Brain abscess
- Intracranial hemorrhage
- Alcohol withdrawal
- Benzodiazepine withdrawal
- Barbiturate withdrawal
- Baclofen withdrawal
- Metabolic abnormalities: hyponatremia, hypernatremia, hypocalcemia, hypomagnesemia, hypoglycemia, hyperglycemia, hepatic failure, uremia
- Eclampsia
- Neurocysticercosis
- Posterior reversible encephalopathy syndrome
- Impact seizure (head trauma)
- Acute hydrocephalus
- Arteriovenous malformation
- Seizure with VP shunt
- Toxic ingestion (amphetamines, anticholinergics, cocaine, INH, organophosphates, TCA, salicylates, lithium, phenothiazines, bupropion, camphor, clozapine, cyclosporine, fluoroquinolones, imipenem, lead, lidocaine, metronidazole, synthetic cannabinoids, theophylline, Starfruit)
- Psychogenic nonepileptic seizure (pseudoseizure)
- Intracranial mass
- Syncope
- Hyperventilation syndrome
- Migraine headache
- Movement disorders
- Narcolepsy/cataplexy
- Post-hypoxic myoclonus (Status myoclonicus)
Diagnosis
- Clinical diagnosis
ED Management
Neuro ICU Management
- Address immediate concerns (ABC’s) (primarily referring to airway/breathing)
- Constantly return to evaluate this for the duration of seizure episode
- continuously monitor O2 saturations via pulse oximetry
- periodic blood gases to evaluate for CO2 retention and lactic acidosis (q10-15mins- up to clinical judgement).
- Constantly return to evaluate this for the duration of seizure episode
- Manage the seizure activity with medications along with investigation/correction of causes.
- Treat quickly; Do not hold medications. Treatment initiated in first 30 minutes has 80% response. Drops to 40% around two hours
- Medication regimes include a benzodiazepine to terminate seizure in immediate term and an anti-epileptic drug (AED) to continue longer term neuronal suppression. Continued seizure activity is treated by additive AED’s and/or sedating medications.
- Very often phenytoin is used for AED (Cost and plethora of studies) however alternatives exist Leveteriacetam, lacosamide, valproate with lesser side effect profile. You may refer to pharmacy for assistance with typical protocol, otherwise phenytoin is acceptable and can always be changed to another AED later.
- Treat quickly; Do not hold medications. Treatment initiated in first 30 minutes has 80% response. Drops to 40% around two hours
- Consider anesthesia consult for possible inhaled anesthetics (isoflurane, desflurane) in OR room for refractory status epilepticus (RSE)
- RSE = continued seizures after 2 - 3 antiepileptic drugs have failed
- Research suggests inhaled isoflurane/desflurane are well tolerated<Mirsattari SM et al. Treatment of refractory status epilepticus with inhalational anesthetic agents isoflurane and desflurane. Arch Neurol. 2004 Aug;61(8):1254-9.</ref>
Take a Stepwise Approach: Timeline
0-5 minutes
- Is this patient still seizing ? (look for return of consciousness) or if on EEG look to EEG (Reading EEGs link to come).
- If this is first episode, may await seizure to break however ready materials to be given should seizure persist greater than 5 minutes
- Protect patient
- turn on side prn for airway protection if vomitting to attenuate aspiration events. Remove any obvious dangerous material that may hurt the patient.
- DO NOT, try to limit patient movement by holding extremities down. DO NOT place bite block (risk of occluding airway).
- Obtain Diagnostic labs (CBC, CEM 10, LFT, coagulation, AED levels (If indicated: assess if therapeutic), ECG, troponins, toxicology screen, pregnancy test (preparation for possible CT), blood gas, continuous SaO2, BP and continuous ECG.
- Ready medications to be given if seizure persists > 5 minutes
- lorazepam (0.1mg/kg max given in 2-4 mg aliquots )
- AED loading agent (Fosphenytoin 20 PE/kg, at 150 mg/min)
- PE = phenytoin equivalents (1.5 mg fosphenytoin = 1 mg phenytoin)
- 20 mg/kg phenytoin is given slower at 50 mg/min
- Thiamine 100mg IV along with 50ml D50IV
- Consider 5 g of pyridoxine (Vitamin B6) over 5-10 min, repeat up to total 20 g, for TB patients with suspected INH toxicity (urban hospital, especially in international medicine)[1][2]
- Briefly familiarize patient H+P to help guide diagnostic causes
- PMHx: Sz History? (get AED levels/home dosages), CNS insults?
- description of previous seizures semiology (if applicable) – jerking/automatisms/gaze deviation
- Medications: anything that reduces seizure threshold?
- Physical Exam: Neuro evaluation
- while in convulsive status patient is obviously seizing and one should continue timeline for acute treatment. The neuro exam is primarily focused on identifying 1. Neuro signs to help localize seizure focus 2.identifying NCSE; focusing on recognizing an improvement of wakefulness/mental status.
- No improvement in wakefulness >20 minutes or continued AMS > 30-60 minutes prompts concern for NCSE and requires 24-48hr cEEG
- while in convulsive status patient is obviously seizing and one should continue timeline for acute treatment. The neuro exam is primarily focused on identifying 1. Neuro signs to help localize seizure focus 2.identifying NCSE; focusing on recognizing an improvement of wakefulness/mental status.
- PMHx: Sz History? (get AED levels/home dosages), CNS insults?
6-10 minutes (seizure persists)
- Administer thiamine 100mg IV along with 50ml D50IV (empirically for possible hypoglycemia)
- May forego if hypoglycemia ruled out with recent CEM panel.
- Administer the 2-4mg lorazepam aliquot over 2 minutes.
- Repeat 1x (max dose 0.1mg/kg) if seizure continues another 5 minutes.
- If no IV access available. Diazepam may be given rectally (20mg PR) or Midazolam (10mg intrabucally/intranasally).
10-20 minutes
- Admin AED loading agent (Fosphenytoin 20 PE/kg). MAX INFUSION RATE 150mg/min
- Phenytoin associated with hypotension. Fosphenytoin use attenuates some of this risk however still significant. Administer with frequent BP checks and ECG monitoring.
- Continue AED maintenance with target phenytoin level 2-3 G/mL after seizure subsides (typically qd checks). Defer to neurology for long term AED management.
- If seizure persists may rebolus 1x with additional Fosphenyoitn 10 PE/kg bolus.
- Phenytoin associated with hypotension. Fosphenytoin use attenuates some of this risk however still significant. Administer with frequent BP checks and ECG monitoring.
- OTHER OPTION
- if patient on AED at home, may reload with home medication: Some examples below
- IV valproate: 20mg/kg over 10 minutes. May re bolus (same dose) 1x if seizure persists > 5 minutes following
- IV keppra 1000-4000mg IV
- if patient on AED at home, may reload with home medication: Some examples below
- Reassess ABC status
- Make arrangements for possible ICU transfer ( If applicable - as next step is intubation).
20-60 minutes (refractory status epilepticus)
- Intubate for airway protection (As we will definitively sedate to the point of respiratory compromise)
- Place arterial line (Continuous BP monitoring with propofol infusion)
- Medications (May use propofol as pressure tolerates, otherwise midazolam; Typically start with propofol since may regain neuro exam faster, and add midazolam).
- IV propofol (causes hypotension)
- 1mg/kg bolus with continued boluses (same dose) every 3-5 minutes until seizures stop (As BP tolerates).
- May place on cIV infusion 1-15 mg/kg/h (Do not exceed >5mg/kg/h in 24 hrs)
- IV midazolam (less hypotension, longer sedation than propofol)
- 0.2mg/kg bolus with repeat boluses (Same dose) every 5 minutes until seizures stop (max dose 2mg/kg)
- May place on cIV 0.05-2.0 mg/kg/h (up to 200mg/h for 70kg patient).
- IV propofol (causes hypotension)
> 60 minutes
- Place in pentobarbital coma
- 5 mg/kg up to 50mg/min. Repeat boluses (same dose) until seizure stop.
- cIV 1mg/kg/h titrated to suppression on cEEG.
Disposition
- Admit
External Links
EM Nerd Adventure of dancing men
See Also
References
- ↑ Weisiger RA. Isoniazid Toxicity Treatment and Management - Supportive and Pharmacologic Therapy. Updated Dec 16, 2014. http://emedicine.medscape.com/article/180554-treatment*d8
- ↑ Vasu T and Saluja J. INH Induced Status Epilepticus: Response to Pyridoxine. Indian J Chest Dis Allied Sci 2006; 48: 205-206.