TIA/CVA Flashcards
Define Transient Ischaemic Attack (TIA)
A disorder of the brain in which brain cells temporarily stop working because of insufficient oxygen, causing stroke like symptoms that resolve completely within 24hrs
Define Cerebral Vascular Attack (CVA)
Rapidly developing clinical signs of focal disturbance of cerebral function, lasting more than 24hrs
2 main types of CVA?
Ischaemic and Haemorrhagic
Ischaemic CVA:
- Brain tissue dies from lack of blood
- Three subtypes: Embolic, Thrombus and Watershed
(Ischaemic) Embolic CVA
- A clot formed elsewhere in the body, moves through the blood vessels and lodges in the cerebral circulation
- May be caused by other emboli such as bone fragments or air bubbles
- Common in people with varicose veins
- Common in people with clotting disorders
- Increased risk following long periods of immobility
(Ischaemic) Thrombus CVA
- Occurs when a blood clot forms in the blood supply of the brain
- Occurs most frequently in people suffering atherosclerosis or clotting disorders
- Often show sudden onset of symptoms
(Ischaemic) Watershed CVA
- Atherosclerotic deposit in carotid artery significantly decreases the total blood flow to the brain
- Decreased blood flow = decreased oxygenation = hypoperfusion and cell death
Haemorrhagic CVA
- Blood vessel ruptures
- Common in people with high blood pressure
- Sudden onset of symptoms
- Leaked blood acts as a toxic liquid, damaging further areas of the brain
Transient Ischaemic Attack (TIA)
- Temporary disruption in blood flow to the brain, resolving in 24hrs
- Resolved by clot dispersing or new neurons taking place of the damaged ones
Signs and Symptoms of CVA/TIA
- Difficulty in speaking/ slurred speech
- Limb power reduced/ absent
- Facial droop
- May have difficulty understanding speech
- Blurred vison
- Severe headache
- Sensation may be affected
- Dilated pupil
- Altered consciousness
- Convulsions
- BP- usually raised
- Hemiplegia
- Assessment tools – FAST, MEND, ABCD2
Risk Factors for CVA/TIA
- Hypertension
- High cholesterol
- Smoking
- Diabetes
(History of TIA, atherosclerosis, hypertension, AF, arrhythmias, rheumatic heart disease, diabetes, orthostatic hypotension, cardiac enlargement, lack of exercise, drug abuse, smoking, family history, sickle cell disease)
Differentials to consider for CVA/TIA
- Bells Palsy
- Hypoglycaemia
- Overdose
Assessment for CVA/TIA
DRA(c)BCDE
DANGER assessment for CVA/TIA
Record time of onset?
- Assess for any potential dangers
- Manage any bleeds
Evaluate if the patient has any time-critical features. FAST positive test.
RESPONSE assessment for CVA/TIA
AVPU - assess