Hypertension and Stroke Flashcards Preview

Human Disease > Hypertension and Stroke > Flashcards

Flashcards in Hypertension and Stroke Deck (30):
1

What does normal blood pressure depend on?

Balance of cardiac output and peripheral resistance

2

What physiological mechanisms are involved in maintaining blood pressure?

Renin angiotensin aldosterone system
Autonomic nervous system
Also : genetics plays a role

3

What happens when low BP, blood volume and sodium plasma levels are detected?

Renin released
Renin converts angiotensinogen to angiotensin 1
ACE converts angiotensin 1 to angiotensin 2
Angiotensin 2 causes vasoconstriction and increased aldosterone

4

What are most cases of hypertension due to?

"essential hypertension" - problem with peripheral resistance, exact mechanism unknown - prolonged smooth muscle contraction

5

What would persistently high BP cause?

Stroke
Heart disease
Renal disease
Visual failure

6

What increases the risk of developing high BP?

Family history
Afro - Caribbean
Obese
Diabetes
Alcohol
Smoking
Sedentary life

7

What value is high BP?

Over 140/90 mmHg

8

How do we test BP?

Sphygmomanometer
Serial clinic readings
Ambulatory BP
Home testing

9

How is BP managed?

Lifestyle changes
Weight loss
Smoking cessation
Reduce alcohol
Exercise
Diet

10

What drugs act on the RAAS?

Calcium blockers and diuretics stimulate renin
Beta blockers inhibit renin
ACE inhibitors inhibit ACE
Angiotensin 2 receptor antagonists (AIIRA) inhibit vasoconstriction in the arteries and inhibit aldosterone release from adrenal gland

11

What is the biggest modifiable risk for a stroke?

Hypertension

12

What is the burden of strokes?

Leading cause of hospital mortality
Second leading cause of death
Major cause of acquired disability
110,000 strokes per year - 1/3 will die, 1/3 will be disabled and 1/3 make a full recovery

13

What is a stroke?

A sudden onset of focal neurological symptoms related to the disruption of the vascular supply to a particular area of the brain, leading to tissue death
Infarction - 80%
Haemorrhage - 20%
Pattern of signs and symptoms is attributable to one part of the brain and a particular vascular supply

14

Name 6 transient focal neurological events?

Partial seizure
Transient global amnesia
Demyelination
Hypoglycaemia
Peripheral nerve compression
Migraine

15

What is a TIA?

Transient ischaemic attack (Differs from stroke only in duration)
Brief episode of neurological dysfunction caused by focal brain or retinal ischaemia
Symptoms last less than an hour
Requires urgent attention

16

What % of strokes are preceded by a TIA?

23%

17

What should happen following a TIA?

Assessment within one week, and within 72 hrs if high risk

18

What is the ABCD2 score?

Predicts risk of stroke at 2 days
A = age
B = BP
C = clinical - weakness / speech
D = duration
D = diabetes

19

What do the results of ABCD2 mean?

0 - 3 low risk
4 - 5 mod risk
6-7 high risk
Anything over 4 should be treated as if they've had a stroke

20

What is the Bamford clasification of strokes?

TACS - total anterior circulation stroke
PACS - partial anterior circulation stroke
LACS - lacunar stroke
POCS - Posterior circulation stroke

21

What comprises a TACS?

Extensive middle cerebral artery infarction
All of:
Contralateral hemiparesis
Contralateral homonymous hemianopia
Cortical higher function loss - dysphagia (dominant hemisphere), visuospatial (non dominant hemisphere)

22

What comprises a PACS?

Branch of the middle cerebral artery
Any 2 of the 3 components of TACS

23

What is lacunar syndrome?

Tiny deep infarcts, usually silent
Unsually internal capsule or pontine
Some symptoms - clumsy hands

24

What comprises POCS?

Ipsilateral cranial nerve defects
Motor or sensory
Disorder of conjunctive eye movement
Cerebellar dysfunction
Contralateral homonymous hemianopia

25

How can a stroke be treated?

PRIMARY PREVENTION - modify risk factors
ACUTE TREATMENT - thrombolysis as long as not due to haemmorhage!!
SECONDARY PREVENTION - lifestyle measures, thromboprophylaxis - anticoags , antiplatelets
REHABILITATION - restores neurological functionality

26

What is a stroke unit?

Multidisciplinary team
Expertise in rehabilitation
Regular in service training for staff
Involvement of carers in patient care
Observations
Advice

27

What occurs on a stroke unit?

Swallow assessment
Pressure sore prevention
Hydration and nutrition
BP management
Active glucose monitoring
Antipyretic treatment

28

What is a carotid endarterectomy?

Surgical removal of the fatty deposits that have built up in the carotid

29

What are the laws for driving after a stroke?

No driving for 1 month
Don't have to notify DVLA in first month after stroke/TIA

30

Why is it good to keep BP high following a stroke?

Keep it raised for 2 weeks to maintain brain perfusion