Flashcards in Hypertension Deck (14):
Increase of systolic and or diastolic BP to point where it increases risk of cardiovascular disease (~140/90mmHg)
Diastolic BP of differing hypertensive serverities and clinical signs
Mild: 90-110, few
Moderate: 100-110, LVH
Severe: >110, LVH, decreased renal function, retinal damage
Malignant: >140, fatal in a few weeks
Secondary hypertension, what is it and what causes it? Treatment?
Caused by an identifiable feature. Treat underlying cause.
Drug induced (contraceptive steroids)...stop pill
Phaeochromocytoma (chromaffin cancer), surgery
Renal stenosis, treat by PCI
What is essential hypertension? Treatment?
Unknown underlying cause! 90%. Decrease risk factors (Na, fat, smoking) and drug therapy.
Drug therapy? When should it be given?
If 2x readings >90mmHg over a time period or if a >20% coronary risk over 10 years.
What would you prescribe to a 55+ white or any age black?
1) Ca++ blocker/diuretic
2) not effective, add ACE/AngII antagonist
3) all 3
4) add b/a blocker
What would you prescribe to a <55 white person for hypertension?
1) not effective, add ACE/AngII antagonist
2) Ca++ blocker/diuretic
3) all 3
4) add b/a blocker
In hypertension, what happens as a result of increased sympathetic nervous system activity?
1) increase RAA, increase arteriolar tone, increase TPR, increase BP
2) decrease Na and water excretion, increase BV, increase CO, increase BP
3) increase CO, increase BP
5 treatments for hypertension?
3) centrally acting anti hypertensives
5) renin angiotensin inhibitors
Explain the use of diuretics in treating hypertension, giving examples of drugs.
Increase sodium excretion, increase fluid excretion, decrease plasma volume, decrease TPR, decrease BP.
Thiazides eg bendromethiazide.
Act at DT, on Na/Cl cotransporter BUT, Potassium loss, increase cholesterol and hyperglycaemia
K+ sparing eg spironalactone (aldosterone antag)...gynecomastia
Eg amiloride (ENaC blocker)...hyperkalemia!
Explain the use of sympatholytics in treating hypertension, giving examples of drugs.
Block effects of S-NS.
Beta antagonists: decrease CO and renin secretion.
Non selective b: propranolol
B1 selective: metoprolol...but bronchospasm, raynauds, rebound hypertension, bizarre dreams (cross BBB), increase plasma fats, decrease gluc tolerance, decrease hyperglycaemia warning signs!
Alpha 1 antag: prazosin...Inhibit NA, dilate arteries, decrease TPR. But initial fainting and dizziness.
A and b non selective. Labetalol (postural hypotension) and carvedilol.
Explain the use of centrally acting antihypertensives in treating hypertension, giving examples of drugs.
Alpha 2 agonists stimulate negative feedback inhibiting nAdr release. Eg, chlonidine
Or...prodrug alpha-methyl-DOPA, converts to a-methyl-NA which also is an a2 agonist!
Explain the use of vasodilators in treating hypertension, giving examples of drugs.
Act on SM of arterioles...decrease TPR and BP but baroreceptor reflex and fluid retention so use with beta blockers and diuretics!
1) VOCC blockers. No Ca in to sm, vasodilation (amlodipine...but headaches and postural hypotension)
2) K+ channel activating drugs...open channels, potassium efflux, hyper polarise, VOCC close (minoxidil...headaches, sweating)
And sodium nitroprusside for hypertensive emergency. Nitro vasodilator....cGMP.