Seizure, Status epilepticus Flashcards
Non-epilepsy causes of seizures?
- Substance intoxication / withdrawal
- Medications
- Fever / Infections
- Stroke
- Brain tumour
- Head trauma
- Electrolyte abnormalities (hyper or hypo)
- Hypoxia (drowning/strangulation)
What is a seizure? Caused by? What causes excitation/loss of inhibition at synapse level?
Refers to visible expression of abnormal, excessive, synchronous discharges of neurons, primarily in the cerebral cortex.
Caused by paroxysmal discharges (sudden attack/firing) from groups of
neurons which arise from either excessive excitation of neurons or loss of inhibition of neurons.
Excitation or loss of inhibition at the synapse level is
caused by malfunction of ion channels in the cells.
How are seizures classified?
Generalised Seizure = loss of consciousness
Further divided into:
- convulsive/tonic-clonic (has tonic-clonic movement + post-seizure mental status change)
- non-convulsive (brief loss of responsiveness with minor motor activity e.g. blinking or staring. No falls occur)
Partial Seizure = NO loss of consciousness
Further divided into:
- simple (tonic or clonic movements, may spread across one side of the body and may have sensory changes)
- complex (pt has aura e.g. nausea, fear, smell, hallucination. Followed by impaired responsiveness. May have stereotyped motor movements.)
What is tonic-clonic movement?
Tonic (stiffening)
Clonic (twitching or jerking)
What is non-convulsive generalised seizure?
Brief loss of responsiveness with minor motor activity e.g. blinking or staring.
No falls occur (no loss of postural tone)
Location of onset for seizures?
Focal onset = seizures that start in one area of the brain or in one network of cells in the brain.
Generalised Onset = seizures that start in networks in the brain on both sides of the brain at roughly the same time.
Unknown Onset = location of onset not known.
Focal to Generalised = seizures start in one area of the brain or one network of brain cells and spread to other areas in both hemispheres.
Awareness of seizure?
Aware = pt is aware of self and the environment during seizure, even if they can’t move or mute.
Impaired awareness = pt may not remember everything but parts of it during seizure. These pts may look alert BUT don’t respond to questions. They may stare off into space.
Unaware = don’t remember anything, usually generalised seizure
Visible motor involvements that may occur during seizure?
Automatisms (repetitive semi-puroseful movements):
* Lip smacking
* Saying same words repetitively
* Hand patting
* Wandering
Tonic:
* Stiffening AND flexure of arms and legs
Clonic:
* Jerking AND twitching movements of arms and legs
Atonic:
* Complete loss of body tone.
* Pt falls to the floor at the start of seizure
Myoclonus:
* Sudden, brief muscle contractions -occurs in single or group of muscles
* Commonly occurs in the arms, but can affect anywhere.
Non-visible motor involvements that may occur during seizure?
Aura
* abnormal sensations -taste/smell/sight/sound
* may occur before or during seizure
Emotions
* agitated
* anxious
* cry or laugh
Autonomic (seizure activity in nerves affecting the ANS)
* BP/HR altered
* flushing
* palpitations
* vomiting
Seizure hx taking?
Ask witnesses / family:
* Do they have a history of seizures?
* Are they on meds? Compliant?
* Typical alcohol use for patient
* Drug use / abuse?
* FH of seizure?
* Current Mental Status? (Alert? Sleepy? Oriented?)
* before, during, after seizure?
What signs to look for from full body exam to look for injuries from seizure or cause of seizure?
- Lacerations
- Tongue injuries from biting
- Bruising
- Fractures
- Clear lungs, soft abdomen, etc.
- Did the patient urinate on herself?
- Clues to any of the common causes of seizure (stroke, tumor, intoxication, electrolyte abn)
Diagnosis/IVx of seizures?
Glucose
CMP (electrolytes)
Pregnancy test
Infectious cause
Screen for alcohol and drug misuse
MRI (structural brain abnormalities, stroke, tumour)
Lumbar puncture
EEG (electroencephalogram -records brain activity)
Management of seizures?
1ST LINE:
Benzodiazepines (e.g. lorazepam / diazepam) -abort seizures
- if seizure lasts >10mins or has 2 seizures within 30 mins = status epilepticus
What is status epilepticus?
A seizure lasting ≥5 minutes
OR
multiple seizures over 5 minutes without returning to a full level of consciousness between episodes.
Presentation of status epilepticus?
Unresponsive
Obvious seizures
- tonic-clonic, tonic only, OR clonic only
Small jerking movements of body or nystagamus of eyes.
Some might have non-convulsive status epilepticus.