Treatment of hypertension Flashcards
(32 cards)
how to find if true hypertension and why
ABPM (ambulatory blood pressure monitoring) and HPBM (home blood pressure monitoring) because normal day to day BP can be very variable so need 20-30 clinical readings (nocturnal dip or loss of nocturnal dip)
do you want nocturnal pressure to be high or low
low. high is very poor prognostic indication
white coat hypertension
gets high BP at doctors but not normally. this can be an indication of future heart problems so not benign
masked hypertension
high BP becomes low when measured at doctors but is normally high
treatment process
assess risk factors, physical examination, assess end organ damage, screen for treatable causes, quantify risk
how to assess end organ damage
ECG, echocardiogram, proteinuria, renal ultrasound, renal function
screen for treatable causes eg
obesity, drugs, sleep apnoea, renal artery stenosis, conns, cushings, phaechromyocytoma, coarctation
how to quantify risk
assign risk calculator, once risk assessed then set a target BP to be obtained, should be perhaps 135/80-85mmHg. treatment started if CVD risk is over 10%
how to treat with drugs
stepped approach, low doses of several drugs, minimises adverse events and maximise patient compliance
what is used to treat hypertension
A (ACE inhibitor/ARB),(high renin) C (calcium channel blocker), D (thiazide- type diuretic) (low renin)
stage 1 hypertension under 80 and ABPM 135/85 are offered antihypertensive drug treatment when
if target organ damage, established cardiovascular disease, renal disease, diabetes, 10 year cardiovascular risk equivalent to 10% or greater
stage 2 hypertension under 80 and ABPM 150/95 are offered antihypertensive drug treatment when
offer antihypertensive drug treatment to anyone of any age with stage 2 hypertension
stage 1 hypertension under 40 and ABPM 135/85 treatment
seek specialist evaluation of secondary causes, more detailed assessment of potential target organ damage
blood pressure target in patients over 80
145/85 so slightly higher
step 1 treatment antihypertensive drug choices
CCB or thiazide like diuretic (African or Caribbean thiazide, caucasian CCB)
who should be offered ACE inhibitors / ARB
patients under 55 but not African or Caribbean as less effective and higher risk of angioedema, women of child baring age as teratogenic
step 2 treatment antihypertensive drug choices
thiazide type diuretic such as indapamide to CCB or ACE1 / ARB
step 3 treatment antihypertensive drug choices
add CCB, ACEI, diuretic together
step 4 treatment antihypertensive drug choices (resistant hypertension)
consider compliance issues, consider higher dose thiazide like diuretic treatment if blood potassium level is higher than 4.5mmol/l, consider further diuretic theory with low dose spironolactone if BP level is less than 4.5mmol/l. (caution in people with reduced eGFR because increased risk of hyperkalaemia)
ACE inhibitors used
(angiotensin converting enzyme inhibitors) ramipril or perindopril. competitively inhibit the actions of angiotensin converting enzyme ACE converts angiotensin I to activa angiotensin II which is a potent vasoconstrictor
contraindications to ACE inhibitors
renal artery stenosis, impaired renal function, hyperkaleamia, fertile female (teratogenic),
ACE inhibitors drug drug interactions
NSAIDs predicate racute renal failure, potassium supplements cause hyperkalaemia, potassium sparing diuretics cause hyperkalaemia
angiotensin II antagonists (ARB)
losartan, valsartan, candesartan, irbesartan. angiotensin II antagonists competitively block the actions of angiotensin II at the angiotensin AT1 receptor. fewer side effects than ACE inhibitors but same outcome
calcium channel blockers
amlodipine/ felodipine (vasodilator for reducing peripheral resistance) or verapamil/ diltiazem (reduces heart rate and produce some vasodilation). block the L type calcium channel in the myocytes of the vasculature and heart
