Uncontrolled Electrical Discharges of Neurons in the Brain

Seizures

Seizure

·  Uncontrolled electrical discharges of neurons in the brain

·  One time occurrence

Preictal State

·  Before the seizure

·  This is where the aura comes in (remember, not everyone has an aura)

Ictal State

·  During the seizure

Postictal State

·  After the seizure

·  Characterized by lethargy and confusion

·  Inability to think clearly, poor attention and concentration, poor short-term memory, decreased talking

·  May last up to a few hours

Seizure Threshold

·  A tolerance point beyond which a seizure can be induced

·  We all have this

·  Once the stimulus goes beyond this point, a seizure will occur

·  Epileptics have a lower seizure threshold than those who don’t have seizures

Epilepsy

·  Medical condition

·  Results in recurrent seizures

Types of seizures

Partial Seizures

·  Affect one side of the brain (one hemisphere)

·  Also known as “focal” seizures

1.  Simple Partial

a. patient stays conscious

2.  Complex Partial

a. patient has a decreased level of consciousness

b. patient may have automatisms or repetitive actions with seizures in the temporal and frontal lobes

c. typically, the patient has an aura

d. examples of automatisms are lip smacking, picking, patting, chewing, swallowing

Generalized Seizures

·  Affect both sides of the brain (both hemispheres)

·  Loss of consciousness

1.  Tonic-clonic seizures

a. also known as grand-mal seizures

b. most common type of seizure

c. begins with a stiffening of the extremities (tonic)

d. evolves into rapid, spastic, jerky movements followed by relaxation (clonic)

e. patient may lose bowel and/or bladder control

f. typically last around 2 minutes

g. may have 30 second periods of apnea

h. patient may have a loud cry before seizure starts

i. patients have an aura

j. patient may become cyanotic during the seizure

k. patient will have a postictal state after the seizure

2.  Absence Seizures

a. also known as petit-mal seizures

b. lapse of awareness

c. may just involve staring into space

d. there is no aura or postictal state

Status Epilepticus

·  Recurrent seizure activity for greater than 30 minutes without regaining consciousness

·  Current research says this activity can cause brain damage at only 5 minutes

Medication

·  For status epilepticus, there is a specific order of medications

1st Line drug: Valium (works quickly, but only lasts a short time)

2nd Line drug: Ativan (takes longer to work, but works longer)

3rd Line drug: IV Dilantin

4th Line drug: Cerebyx

5th Line drug: Phenobarbital (severe side effects-bradycardia & hypotension)

6th Line drug: Valproates (hepatotoxic)

Aura

·  Telltale sensation felt by some people who experience seizures

·  May manifest as bright lights, sounds, smells, taste

·  Most times, people have the exact same aura sensation every time

·  An aura allows time for an epileptic to lay down somewhere safe

Causes (not all seizures are related to Epilepsy)

·  Brain tumor

·  Hypoxia

·  CVA

·  Alcohol or drug withdrawal

·  Eclampsia

·  Excessive sounds and lights

·  Fever

·  Head trauma

·  Heat stroke

·  Infection

·  Diabetes

·  Electrolyte imbalance

Diagnostic

EEG

·  Primary test

·  Most reliable

·  Gives us the ability to differentiate an actual seizure with seizure-like activity

·  Similar to an EKG, an EEG shows electrical activity in the brain

·  Electrodes are placed all throughout the head with conductive gel

Preparation

·  No chocolate, tea, sodas, caffeine, or nicotine for 24-48 hours before the test

·  Doctor may hold sedatives, tranquilizers, and/or anticonvulsants if they are trying to induce a seizure

·  Patient does not have to be NPO

·  Patient should wash his hair the night before, but do not use conditioner

·  Remind the patient that this a painless procedure

Video EEG

·  Coordinates what’s on video with what’s going on in the brain

·  Determines if signs/symptoms can be tied in brain activity

·  Prep is the same for EEG

CT

·  Called SPECT (Single Proton Emission Computerized Tomography)

·  Does not diagnose seizures, but will localize the area in the brain where seizures are occurring

·  Sometimes used prior to surgical intervention, where the surgeon removes the diseased part of the brain

MRI

·  Used to detect structural lesions, cerebrovascular abnormalities, and cerebral degenerative changes