Pathophysiology of tonic clonic seizure

Pathophysiology of tonic clonic seizure

1. PATHOPHYSIOLOGY
Etiology:
Altered integrity of
neuron in the
epileptogenic focus
PRECIPITATING FACTORS:
·Sensory stimuli: loud noises
or bright lights
·electrolyte imbalance
PREDISPOSING FACTORS:
·Family History
Activated by
precipitating factors
Abnormal spontaneous
spread electrical
discharges
Partial depolarization
(high voltage electrical discharge)
Partial stimulation of
neurotransmitter molecules
Imbalanced release in excitatory
and inhibitory neurotransmitters
Lowered seizure threshold
Hyperexcitablity state of neurons in
the epileptogenic focus

2. Spreads to both
hemispheres
Clonic phase:
·Muscles will contract
and relax rapidly
·Violent, jerking
movements
·Upward rolling of the
eyeballs
·Bowel and urine
incontinence in some
Post-ictal phase:
Due to physical and nervous
exhaustion, the patient may
have/ will be:
·Semiconscious
·Poor coordination
·Mild impairment of fine
motor movements
·Deep sleep
Hyperexcitability of neurons
in the brainstem causing
disruption in the functions of
the medulla, pons and
midbrain
Tonic Phase
Disruption in
medullary
activity thus
alteration in
function of
respiratory and
cardiovascular
system
Cessation of
cardiovascular and
respiratory activity
causing apnea and
cyanosis.
Alteration
in the
activity of
the pons.
Musculature
stiffening( extr
emities pulled
toward body)
Alteration in the activity
in the midbrain (connects
brain to spinal nerves)
Loss of consciousness
and swallowing reflex
Inhibitory impulse starts
from the thalamus and
interrupts the tonic phase
into discontinuous bursts
of electrical activity