Hypertension Flashcards
1
Q
what is hypertension?
A
- a sustained increase in blood pressure.
2
Q
differentiate between essential and secondary hypertension.
A
- ‘essential hypertension’ in where cause in unknown which is the case for 95% of the time.
- ‘secondary hypertension’ is where cause can be defined and is usually chronic renal disease, renovascular disease. important to identify underlying cause to treat it.
3
Q
why is it important to treat hypertension? what might the long term complication be?
A
- damaging effects to heart and vasculature as increased afterload leading to LV hypertrophy and higher O2 demand.
- arterial damage by weakened vessels leading to aneurysms, atherosclerosis.
- lead to heart failure, MI, stroke, renal failure and retinopathy.
4
Q
define mean arterial BP.
A
- CO X TPR
CO = SV X HR
5
Q
how is BP regulated?
ON PAPER NOTES IN MORE DETAIL.
A
- short term regulation : baroreceptor reflex.
- long term : neurohumoral response, sodium balance and reabsorption.
6
Q
how is secondary hypertension caused by renovascular disease?
A
- occulusion of renal artery (stenosis) causes a fall in oerfusion in that kidney, causing increased renin.
- RASS activated, vasoconstriction and NA+ retention at other kidney.
7
Q
how is secondary hypertension caused by renal parenchymal disease?
A
- early stages maybe loss of vasodilators.
- later stages Na+ and water retention due to inadequate filtration.
- causes volume dependent hypertension.
8
Q
how is secondary hypertension caused by other adrenal causes?
A
- conn’s - aldosterone secreting adenoma.
- cushing’s - excess of glucocorticoid cortisol acts on aldosterone receptors increasing retention.
- tumour in adrenal medulla.
