Stroke Flashcards
What is stroke
WHO defines stroke as acute sudden onset of focal/ global neurological deficit which lasts more than 24 hours or results to patients demise which is due to cerebral vessels diseases
What is T I A
Is a brief episode of neurological dysfunction due to temporary focal cerebral or retinal ischemia without infarction lasting second to minutes and there is complete recovery
What is the epidemiological significance of stroke
*3rd most common cause of death
*Most disabling neurological disorder worldwide
*2/3rd cases occur in age 65 years
* stroke in the young : is stroke in people less than 45 years
Classification of stroke
- Ischemic stroke; account for 80%
.2 Haemorrhagic stroke; 15- 20%
Risk factors of ischemic stroke
Modified and non- modified ischemic stroke
Modifiable risk factors; these are further subdivided into;
.i arterial factors
Ii. venous factors
Arterial factors: modifications
1.DM
2.Uncontrolled
systemic hypertension
3:Dyslipidaemia e X(Reaven’s I V.
Metabolic syndrom
syndrome); combination of hte 3 with central obesity
4. Cardiogenic factors like
afib (commonest), valvular heart disease, subacute bacterial endocarditis,
dilated CM, rheumatic heart disease and DVT (in the presence of septal defect/ shunt i.e. paradoxical embolism)
5:Tobacco smoking
6 Sedentary lifestyle
ix. Drug abuse
.x Connective tissue disorder xi. Vasculitides
7.Severe alcohol consumption
Venous factors
Venous
factors; cause hypercoagulability state
.i Pregnancy
Immediate post-partum
i. Deficiencies of protein C and S, factor Vleiden deficiency
vi. Hyperhomocystinuria
.v Intracranial infection
vi. Oral contraceptive pills
vi.Dehydration
Non modifieable risks
.i Age
i. Previous history fo stroke
ii. Family history fo stroke esp 1st degree relatives
vi. Gender; M>F fi <55YEARS, M=F after menopause
.v Race; afrocarribean> Asian>Caucasian
v.i
Hereditary stroke disorders; CADASIL, CARASIL etc
Mention 7 Risk factors hemorrhagic stroke
1.Severe hypertension
2.Bleeding disorders
3.Anticoagulants
4.Antiplatelet drugs
5.Pre-existing cerebral aneurysm
6.Vascular malformation eg AVM 7.Trauma
Common sites; of stroke in the brain
- putamen (30%)
*Thalamus(30%)
*pons(10)
*cerebellum(10)
*others
Pathogenesis of neuronal death;ischemic stroke
*Ischemic stroke: Decrease cerebral blood flow, (<15ml/gm/min) i.e ischemic necrosis Normal=
50-70 ml/gm/min
* Na/Ca influx
* Necrotic cell death
(window period=3 hrs, max 41/2 hrs)
*Programmed cell death (apoptosis)
Pathogenesis of neural cell death hemorrhagic stroke
.i mass effect on neuronal tissues
i. toxic effect of blood itself
iii. tamponade of
surrounding
Classification of clinical diagnosis of stroke
1.Anatomical diagnosis
2.pathologic diagnosis
Anatomic diagnosis; locations
1.cortical, : aphasia, dysarthria, differential limb, w e a k n e s s, lateralising, hemianopsia,
Broca’s/Wernicke aphasia).
2.subcortical : dense ,hemiplegia, tremor, hemiparesis
3.brainstem: stroke; contralateral hemiparesis, cranial nerve palsy /deficit, dysathria, dizziness, respiratory or cardiovascular instability
Pathological diagnosis
Ischemic stroke vs hemorrhagic
1:Onset:hemorrhagic-Usually during peak of activity , ischemic stroke: Usually at rest
2:loss of consciousness: hemorrhagic stroke:usually present , ischemic stroke:maybe present
3: Headache:hemorrhagic stroke;severe throbbing headache, ischemic stroke:headache maybe be present
4: Convulsion:hemorrhagic stroke:there is convulsions ,ischemic stroke: No convulsions
5: Vomiting:hemorrhagic stroke :there is vomiting , ischemic stroke: No vomiting
6: Blood pressure: hemorrhagic stroke : there is severe high blood pressure,
7.Symptoms increase ICP; hemorrhagic stroke:There is marked
ICP,ischemic stroke not marked
8: Hx of past TIA: hemorrhagic stroke:No hx of TIA, ischemic stroke: There is hx of TIA
9: Meningism:HS: yes/No, ischemic stroke:No meningism
Investigations of stroke most important
Non contrast CT scan : scan of the
head; is the single most important investigation in stroke.
1:ischemic stroke : Hypodense lesion
2:hemorrhagic stroke : lesion
Hyperdense lesion, a; perilesional edem area of hypodensity surrounding the lesion.
Swell sign; scattered hypodensed points within the hyperdense lesion. It indicate on going bleeding
Common CT features
- Midline shift to contralateral side
- Obliteration of gyri and sulci( cerebral edema)
- Obliteration of ventricular outline : ipsilaterally
General investigations of stroke
-Serum E, U/ Cr; detect electrolyte imbalance and renal compromise
-RBS; glucose status, and need for insulin (RBS >12mol/1)
-Urinalysis;
-FBC and differential to rule out:infection
-Lumber puncture; rule out SAH, meningitis
-Chest X-ray
-ECHO; rule out cardioembolic source
-Lipid profile
-Coagulation profile; PT/PTTK
-VDRL
-ESR
Treatment of stroke
*Aim is to salvage the penumbra. Treatment is divided into 3;
1. Hyperacute treatment (within 6 hours)
-Admit patient
-nurse 30 head up
-Give high flow 02
-Secure VI access and give ivf use N/S avoid dextrose containing fluid
* Decompress
- 20% mannitol 0.5-1gn/kg in 500mls over 20mins 8hrly in 24 hrs ( maximum 48hrs)
*Low dose furosemide may be
given. Steroid is not useful because edema is cytotoxic
-Thrombolytics: if patients present 3-5hrs
-Statins; plaque stabilizing
-B.P control; BP should not be lowered except t h e r e are certain indications.such as
* Persistent systolic BP >120mmhg
*DBP >120 mmhg
* Persistent MAP > 145mmhg
* Presence of hypertensive emergencies; dissecting aortic aneurysms , preeclampsia/ eclampsia.
2: Acute treatment
-Patient still on admission
-Continue IV fluid
-Start physiotherapy
-Prevent aspiration pneumonitis e.g NGT
-Give IM paracetamol for fever a n d
anticonvulsants for seizure
-Give insulin if RBS >12 mmol
-Calorie- provide adequate
* DVT prophylaxis;
-Compression stockings
-Low dose aspirin; contraindicated in hemorrhagic stroke
* Prevent bedsores;
-2hourly turning
-use of waterbed
-Pass a Paul’s tube for male and urethral catheter for
female patient with urinary incontinence
Identify underlying cause and address appropriately Surgery eg multiple bore hole/ brain flaps to decrease ICP by <1-2%.
Continuing treatment
Sub-acute treatment 2( weeks) of stroke
Monitor patient for discharge -
CT physiotherapy
Give outpatient appointment - CT treatment of underlying cause
Complications of stroke
:Acute complications
A. Acute complications (24-72 hours) .i I.Aspiration pneumonitis
i. Post stroke seizure
i. Cerebral edema
iv. Dehydration
.v Electrolyte imbalance
Subacute complications of stroke
Subacute complications
i.Sepsis; from NGT, catheter,IV line i.DVT
iii.Bedsore iv.Hyperthermia v.Hyperglycemia vi.PEM
vii.Dehydration
Chronic complications of stroke
i.Depression
ji.Dementia
i. Loss of job
iv.Epilepsy
v.Muscle wastage (disuse atrophy) vi.contacture
Prevention of stroke
i.good BP control
Ii.good glycemic control
iii. prophylactic antiplatelets aspirin, clopidogrel
Differential diagnosis of stroke
i.brain tumour
ii.brain abscess
iii.subdural hematoma
iv.epidural hematoma
v.ruptured SAH
vi.migraine
vii.seizure disorders
