Seizures – ED

Seizures

1. Consider the possibility of a seizure in the differential diagnosis for a patient with an atypical presentation but without witnessed frank seizure movements (e.g., confused or altered level of consciousness, incontinence, fall/injury/accident, tics in children).

Classifications

1. Generalized
   1. tonic-clonic / Grand Mal
   2. Absence / Petit Mal: <1min staring spells
   3. Myoclonic
   4. Atonic
2. Simple partial – consciousness maintained & no post-ictal
   1. Motor: focal tonic movement; Jacksonian march (simple partial progressing to generalized seizure)
   2. Sensory: visual, auditory, oral, olfactory, gustatory
3. Complex partial (temporal lobe) – no LOC ,but AMS/impairment +/- amnesia
   1. automatisms: lip smacking, repeated swallowing, picking at clothes
   2. hallucinations: olfactory/gustatory – temporal lobe; visual – occipital
   3. may have postictal confusion
4. Pseudoseizures / PNES (psychogenic non-epilepticus Seizures)
   1. no postictal, acidosis, leukocytosis
   2. normal prolactine level and plantar reflex

2. Given a patient with a seizure, investigate for rapidly reversible causes (e.g., hypoglycemia, toxicology, arrhythmias) and treat promptly.

Secondary causes

1. Metabolic:
   1. Hypoglycemia (DM), Hyponatremia (neonates/infants), hypocalcemia
2. Drugs & toxins
   1. anticholinergics/ cholinergics/ sympathomimetics
   2. Antidepressants / toxic alcohols / Mushrooms (gyromitra sp)
   3. Alcohol W/D: BZD/thiamine Tx of choice; may need intubation + phenobarb vs propofol
   4. Drugs: theophylline (asthma), INH (Injures Neurons & Hepatocytes – TB), baclofen w/D; TCA OD (bicarb)
3. CNS infection – encephalitis / meningitis
4. CNS lesions / trauma: neurocysticercosis, hemorrhage, tumors, stroke, vasculitis, hydrocephalus
5. Febrile – simple (<15min, <2/24hr, 6mo-6yo) vs complex; antiepileptics not indicated
   1. prevalent family; Sz w/u not req if simple febrile Sz
   2. LP if: Meningeal signs, <12mo w/o HiB or S. Pneumo Imm, Febrile status epilepticus
   3. risk factor for recurrence: <12mo, lower temp and shorter duration of fever at onset, + family hx, complex febrile Sz
6. Eclampsia
7. Pseudo – hysterical epilepsy
8. Syncope / arrhythmia – ECG for all Sz patients

3. Given a patient with ongoing repeated seizures or persistent altered mental status between seizures, make the diagnosis of status epilepticus and treat promptly.

Status epilepticus

• Sz >5min or >=2 Sz w/o fully recovery of consciousness between seizures
• Pt may have EEG discharge even after tonic-clonic movements ended; Must monitor EEG after intubation + paralyzed

4. In a patient who continues to seize actively, manage by:

• Assessing the airway and ventilation and supporting as necessary

• Identifying specific conditions that require treatment other than standard anticonvulsant therapy (e.g., pre-eclampsia, toxidromes)

Reversible causes

1. infectious – consider empiric abx and acyclovir
2. Eclampia – up to 6wk postpartum – consider empiric MgSO4 4-6g IV
3. Isoniazid toxicity – antidote: pyridoxine 5g IV
   1. consider tox causes if unresponsive to drug therapy
4. Hyponatremia – 100ml (2ml/kg) 3% hypertonic saline; repeat 10min prn
   1. HypoCa/Mg – replace
5. EtOH W/D – needs more BZD / thiamine
6. Cyanide – antidote: hydroxycobalamine and cyanide antidote kite – sodium thiosulfate
7. Structural brain dz if focal Sz – obtain CT
   1. tumor – steroids

• Using anticonvulsants in a progressive fashion to terminate the seizures as promptly as possible

Management of status epilepticus:

1. airway – roll pt on side to dec aspiration, establish patent airway, suction prn & oxygen through non-rebreather facemask
2. BZD: Ativan 0.1mg/kg IV & search for reversible causes
   1. consider eclampsia up to 6wk pp – treat empirically w/ MgSO4 4-6g IV
   2. Midazolam IV/IM/IN; Diazepam IV/PR; Ativan IV/IM
   3. Thiamine and glucose if hypoglycemic / EtOH
3. Check BG, lytes, tox, HCG, liver and renal function
4. Phenytoin / fosphenytoin (IM/IV) 20mg/kg IV over 10min & prepare for intubation
   1. Give second dose of BZD at the same time – Ativan 0.1mg/kg IV
   2. Phenytoin – nystagmus if therapeutic
5. Valproic acid 20mg/kg IV or Keppra 40mg/kg IV good safety profile
   1. useful in HoTN, noncompliance to oral valproic acid, sensitive to phenytoin
6. Intubation – RSI; avoid Etomidate – lowers Sz threshold
   1. induction w/ propofol 1.5mg/kg IV (anti-epileptic), but if HoTN, use Ketamine 2mg/kg
   2. Paralytics – use succinylchoine – watch out for hyperkalemia; rocuroniym increase the risk of nonconvulsive status epilepticus
   3. Consult neuro for EEG to r/o nonconvulsive status epilepticus
   4. Phenobarbital 20mg/kg – respiratory depression, HoTN, long half life
      1. some guideline recommends skip phenobarbital and right to propofol
7. Obtain CT head and consider LP

5. In a patient who has had a first seizure, counsel regarding high-risk activities and initiate the appropriate procedures for reporting to authorities (e.g., driving/sports/occupation).

No driving, swimming, Bath, other high risk activities

6. Given a patient with a first seizure, investigate to establish the underlying etiology in a timely fashion (e.g., CT, lumbar puncture, EEG, metabolic, toxicologic).

DDx: syncope, dysrhythmia, psychiatric illness, migraines, CVA, SAH

First Time Seizure

• check Na, Glucose, Ca, Mg, bHCG, urine toxicology
• CT if any suspicion for serious structural lesion
• LP if any suspicion for meningitis, SAH, hx of cancer ? mets to brain
• HIV pt – CT with contrast / MRI
• EEG during event confirms diagnosis if diagnosis is in question; Out paitent follow up for MRI/EEG if no cause found in ED.
• Defer initiation of antiepileptics to outpatient neurology unless CNS lesion present

7. In a known epileptic who has had a seizure, investigate appropriately but do not over-investigate without specific indication (e.g., verify compliance and check anticonvulsant levels, consider contributing causes).

Precipitating factors

• missed medications
• substance abuse or withdrawal
• sleep deprivation
• infection
• electrolyte disturbances

Recurrent Seizures

• check glucose and anticonvulsant levels – supratherapeutic level of phenytoin and carbamazepine can result in Sz
• More extensive evaluation if change in Sz pattern, prolonged postictal or fever
• Consider medication adjustment

8. In a child with a typical febrile seizure, including a complete recovery, make a diagnosis based on history and physical exam alone, and do not over-investigate.