Patho & Pathophis week 2 Flashcards
Can Hypoxia be diffuse (widespread)
YES! Hypoxia is where there is a lack of oxygen in the brain and depending on where the blockage is in the brain it can be wise spread
How long does the glucose and glycogen stores last
If blood flow is not restored quickly enough with in
2-4 mins glucose & glycogen stores are exhausted
4-5 mins is when cellular ATP stores are depleted
What does a influx of Sodium and calcium have on the brain
Excess sodium: causes neuronal & Interstitial oedema
Excess calcium: Initiates events causing cell death
How do you define a stroke
It is the sudden impairment of cerebral circulation resulting in injury/death of brain tissue.
What can a Primary Hemorrhagic stroke be broken into
- Intracerebral
- Subarachnoid
What are 3 different types of primary ischemic stroke
- Thrombotic blood clot blocks blood flow
- Embolic clot travels from somewhere else in the body and blocks an artery in the cerebral cavity
- Lucunar is the most common type of ischemic stroke this is where there are occlusions to penetrating arteries providing blood to deep structures in the brain
What is Collateral circulation?
This is where other arteries and capillaries can supply the part of the brain that is affected
What are the 2 language defects associates with strokes
Dysarthria: speech disorder, imperfect articulation of sounds or changing
Aphasia: is a partial or total loss of language
What are some risk factors for strokes
What is the different between a thrombolic & an embolic stroke
Thrombolic: is a occlusion that originates in the brain blocking blood flow to an area in the brain
Embolic: is a occlusion that originates somewhere else in the body and moves to the brain
What does stenosis mean
Narrowing of vessel
What are the common symptoms of a thrombotic stroke
What is a TIA
This is a temporary disturbance in focal cerebral blood flow causing ischemia and hypoxia, however reverses before infarction occurs. symptoms usually resolve themselves in minutes to hours
Can a TIA cause irreversible damage to brain tissue
TIA’s don’t cause irreversible damage because the clots resolves itself in time, but TIA’s are indications that there might be another larger vessel stroke prevalent
What causes a TIA
TIA’s are still caused by atherosclerosis in cerebral vessels or an emboli from another area. however it still irritates the neuronal cells causing ischemia and hypoxia so symptoms are still prevalent
What is a Lacunar stroke
There are very small infarcts in deeper non-cortical parts of the brain or in brain stem
What is a embolic stroke
This is where the embolism travels from its origin to the brain. These usually show as sudden onset and immediate deficit symptoms
Note: These often originate in the heart and are often caused by AF
What are some other conditions that increase the risk of a Embolic stroke
Rhematic heart disease
Resent MI
Ventricular aneurism
Mobile aortic arch atheroma (degeneration of arterial walls cause by accumulation of fatty deposits and scar tissue causing restriction of circulation)
Bacterial carditis (infection of endocardium)
What is a hemorrhagic stroke
It is the most fatal stroke.
It is the sudden rupture of cerebral blood vessels either in intracerebral or subarachnoid.
this can cause focal hematoma, oedema, rise in ICP, exerts pressure on the brain. This can progress rapidly into coma & often death
These usually come on with physical activity
Some common symptoms are headache, vomiting seizures & LOC
What are predisposing factors for a hemorrhagic stroke
Age
Hypertension
Trauma
Tumors/blood coagulation Disorders
Vasculitis
Drugs
What is a subarachnoid hemorrhage
This is a rupture into the subarachnoid space which can spread far from site of bleed
Commonly occurring in the circle of Willis
Usually occurring with out prior symptoms, although associated with prolonged hypertension and arterial degeneration
Mortality & morbidity is high
What are some symptoms of a intracerebral hemorrhage
Sudden headache
Decreased LOC
Hemiplegia
Possible seizures
What are predispositions to intracerebral hemorrhages
Hypertensive atherosclerosis & cerebral amyloid angiopathy (where proteins build up on the walls of small to medium blood vessels of the CNS and meninges)
What are key facts of strokes
What is the Ischemic Penumbra
This is the central core of dead/dying cells destined to die after strokes. Survival of these cells determine on how quickly they get adequate blood flow and oxygen back.
Stroke symptoms for different sides of the brain
What is Bell’s palsy
This is a inflammatory disease of the facial nerve, causing inappropriate neural stimulation of muscle fibers
How long does this last and does it affect both sides of the face
This can affect bilateral or unilateral sides
usually resolving in 1-8 weeks
What are some risk factors to Bell’s palsy
Tumor
Diabetes
Pregnancy
Upper respiratory tract Infection
Trauma
What is Meningitis
This is the inflammation of the brain & spinal cord meninges (all 3 layers)
Is viral meningitis more serious then bacterial?
No viral meningitis is more Common
Bacterial meningitis is more Serious
What is the Patho of Meningitis
Why can meningitis cause amputation
This is because the blood is redistributed to vital organs making the peripheral circulation poor resulting in ischemia and eventually hypoxia of the cells
What is a common acronym for unconsciousness
A - Acidosis, Alcohol
E - Epilepsy
I - Infection
O - Overdose
U - Uraemia (kidney failure)
T - Trauma, Tumour, Toxin
I - Insulin (Hypoglycaemia or DKA)
P - Psychosis, Poison
S - Stroke, seizure
How do you define a seizure
Temporarily abnormal behaviour caused by an electrical discharge from 1 or more groups of neurons in the brain
Why are seizures dangerous
They can cause hypoxia, rapid lowering of BGL & Hyperthermia
What does idiopathic Epilepsy mean
Idiopathic means that there are no known cause. 50% of cases are Idiopathic
What are the 2 catagories that Epilepsy can be broken into
What is the main different between Focal and Generalized seizures
What are the 2 catagories that Generalized seizures can be broken into
What are the major motor sizures
Tonic Clonic
What are Absence Seizures
These are generalised Non-convulsive causing disturbance in consciousness.
Typically occurring in children.
Characterised as blank stare motions, can be gone unnoticed
Focal Seizures
Pro-dome is where someone can determine if they are going to have a seizure this can be days or hours before seizure activity starts
Aura happens right before a seizure starts and is a warning that one is about to happen.
What are some symptoms of Auras
Dejavu
vision problems
Dizziness
Headache
nausea
vision problems
odd smells/taste
Numbness or pins and needles
feeling of intense fear
(NOT ALL PATIENTS HAVE AURAS)
What is a temporal lobe (complex focal seizure)
This seizure begins in a localised area & may progress to both hemispheres
The Auras are
unusual smell, taste smell or visual disturbances
What is status epilepticus
Is someone who has had a seizure for longer than 30 mins or has had multiple & the patient has not retuned to their normal GCS.
What is the Postical state
There is post seizure and can present with tiredness, confusion, agitation & amnesia. this usually last 5-60 mins
What are some indications the patient could be continuing to siez
Rhythmic eye movements, dilated pupils, persistent tachycardia or failure to improve they could still be seizing
