Lecture 11 Flashcards
Who can have hypertension?
Anyone
Steroids-gym attenders OR elevated BMI
Why is hypertension dangerous?
Because it is a silent killer- there are no symptoms
What is hypertension?
Sustained increase in BP
What is BP measured in?
MmHg
What is the normal BP range?
90/60 mmHg - 120/80 mmHg
What are the different classifications of hypertension?
High normal is near the stage 1 cut off
Stage 1: >/= 140/90 mmHg (135/85 mmHg for in ambulance/at home as it is lower here than in the GP)
Stage 2: >/=160/100 mmHg n
Severe hypertension: >/= 180/110 mmHg
What is hypertensive urgency/emergency?
Any rapid change in BP associated with damage to body
Rather than sustained increased in BP
What is primary/essential hypertension?
When the cause of the high BP is unknown
95% of cases
What is secondary hypertension?
Cause of BP is found (important to identify & treat underlying cause)
E.g. renovascular disease, chronic renal disease, hyperaldosteronism, Cushing’s syndrome
What effects does hypertension have?
-damage to heart and vasculature
(Potentially leading to heart failure, MI, stroke, renal failure, retinopathy)
-that is why it is essential that we primary prevent, rather than secondary prevent (after a health issue has occured)
Which major diseases do people with high BP tend to experience?
All vascular diseases
- stroke
- heart failure
- cerebral haemorrhage
- chronic kidney failure
- MI
- coronary heart disease
- retinopathy
- aortic aneurism
How does hypertension cause heart failure?
Increased afterload
-left ventricular hypertrophy
How does hypertension lead to MI/myocardial ischaemia?
- increased afterload
- increased myocardial oxygen demand due to increased workload
- arterial damage
- atherosclerosis
How does hypertension cause aneurysm/retinopathy/renal failure/stroke?
Atherosclerosis/weakened vessels
-arterial damage
What do you examine when a patient comes in with hypertension?
Look at their vasculature and take history of any vascular diseases
- brain: stroke/vascular dementia
- eyes: retinopathy
- heart/ECG
- chest pains/MI
- urine tests/image kidneys
- look at HR
What is vascular target organ damage?
- left ventricular hypertrophy
- retinopathy
- MI
- atherosclerosis of aorta
- ischaemic stroke
- inter-cerebral haemorrhage
- chronic kidney disease
Is treating high BP effective?
Yes it lowers changes of end target organ damage
For every 10 mmHg reduction in BP:
-17% reduction for coronary heart disease
-27% reduction for stroke
-28% heart failure
-13% reduction in all cause mortality
What is the equation for your mean arterial blood pressure?
Mean arterial BP = CO x TPR
CO = SV x HR
How is blood pressure regulated short term?
Baroreceptor reflex
(Short term- bleeding to death/septic shock)
-body senses low BP via baroreceptors
-increased stretch by increased BP of baroreceptors stimulates them, decreased BP stretches them less
-baroreceptors send messages to medulla in brain, feeds back to heart/peripheral vessels to adjust HR/TPR-via dilation
Bradycardia/vasodilation counteract increased mean arterial pressure
Where are baroreceptors abundantly found?
-carotid sinus
-aortic arch
(Sensitive to stretch: monitor BP coming out of the heart)