Hypertension Flashcards
Definitions of prevention?
primary prevention- prevent diseases from occurring
secondary- prevent diseases from recurring/ progressing
tertiary- reduce complications of established disease
When should you suspect hypertension?
Suspect hypertension when:
Clinic SBP ≥140 and/or DBP ≥ 90 mmHg
Ambulatory blood pressure monitoring (ABPM) average:
SBP ≥135 and/or DBP ≥ 85
What does hypertension increase risk of?
Heart failure
Coronary artery disease
Aortic syndromes
Stroke
Chronic kidney disease
Peripheral arterial disease
Vascular dementia
Visual impairment
Why do people get high blood pressure?
Primary hypertension
- No single cause identified (genetics/
environment)
- 90%
Secondary hypertension
- 10%
- Renal disease (inc. renal artery stenosis)
- Endocrine disease (inc. Cushing’s, Conn’s, phaeochromocytoma)
- More common in young patients
- Refer those aged < 40 years to a specialist
Risk factors of having high blood pressure?
Birth weight
Age
Deprivation
Genetics
- inc. race/ ethnicity
Lifestyle
- Obesity
- Stress
- Smoking
- Alcohol
- Stimulants
- Lack of exercise (acutely increases, long term decreases)
Co-morbidities
Iatrogenic
What systems are important for the autoregulation of BP?
RAAS- renin angiotensin aldosterone system
Endothelium
SNS - sympathetic nervous system
immune system
Natriuretic peptides
How does sympathetic activation work?
how sympathetic activation increases your blood pressure
vasoconstrict
reflex tachycardia
increased stroke volume
stimulates renin release
What is RAAS stimulated by?
- Fall in BP
- Fall in circulating volume
- Sodium depletion
Any of the above stimulate the release of renin from the juxtaglomerular apparatus
How does the RAAS system work?
drop in blood pressure , drop in fluid volume stimulates renin release from kidney
renin acts on liver made angiotensin to form angiotensin I
angiotensin I waits for ACE (angiotensin converting enzyme) to be released from lungs
ACE acts on angiotensin I to form angiotensin II
Angiotensin II causes vasoconstriction and acts on adrenal glands to stimulate aldesterone
aldesterone acts on kidneys to stimulate water and salt retention
methods of assessing end organ damage?
ECG
Urinalysis- proteineuria
Blood tests- renal function
Echo
Eye test- bad hypertensive eye disease
Treatment options?
stage one- think about ten year risk. If ten year risk is high discuss drugs and lifestyle but if low just lifestyle and then reevalulation of bp
stage two hypertension- jump straight to drugs and discuss lifestyle
less than 40 years old- specialist service
What treatment for hypertension without type 2 diabetes, over 55, black african or afro carribean?
calcium channel blocker initially
What treatment for those who arent?
ACE inhibitor or ARB
What if blood pressure is still not controlled? (Stage II)
add other treatment you haven’t added yet to each one
to ACE or ARB add CCB or thiazide-like diuretic
to CCB add ACE or ARB or thiazide like diuretic
Stage (III) treatment?
ACE or ARB + CCB + thiazide like diuretic
Stage IV treatment?
spironolactone
alpha blocker, beta blocker
How do ACE inhibitors work?
if inhibit ACE (angiotensin converting enzyme) - inhibit conversion of angiotensin I to angiotensin II
angiotensin I does nothing
Effects of ACE inhibitor?
side effects:
-cough
-angioedema
-don’t take when ill as would dehydrate even more
Should you give ACE inhibitors to pregnant women?
no
Where to have caution when prescribing ACE inhibitors?
-renal artery stenosis- can tank renal function
-CKD (Chronic Kidney disease) - ACE inhibitors typically protective in CKD
What drug interactions are bad for ACE inhibitors?
NSAIDS
Potassium supplements/ potassium sparing diuretics - ACE inhibitors increase potassium levels
How do angiotensin II receptor blockers work?
Stops ACE acting on angiotensin I to form angiotensin II
What are the central and peripheral calcium channel blockers?
peripheral- nifedpine and amlodiopine
(work on blood pressure)
central- verapimil and diltiazem (work on heart as rate limiting)
What are the dihydropyridine CCBS?
ones that act peripherally
What are the non Dihydropyridine CCBS?
act mainly on heart- reduce heart rate
How do calcium channel blockers work?
inhibit movement of calcium by binding to L type calcium channels receptors
Side effects of CCBS?
leg swelling
dry mouth
bradycardia- if given non dihydropiridine
Drug interactions to avoid with calcium channel blockers?
do not prescribe verapimil with a beta blocker
What are examples of thiazide like diuretics?
indapimide
What does a low dose of thiazide like diuretics cause?
low doses mainly vasodilates
What do high doses of thiazide like diuretics cause?
diuretic effect
What effect can be observed when combined with loop diuretic?
profound diuretic effect
side effects of thiazide like diuretics?
hypokalaemia
hyponatermia
Where do thiazide like diuretics work?
at the distal convoluted tubule
inhibit sodium and chloride symporter and lose sodium-lose water
Examples of mineralocorticoid receptor antagonists?
spironolactone, eplerenone
How do mineralocorticoid receptor antagonists work?
Inhibits the action of aldosterone at the DCT/CD
Potassium sparing
Side effects of mineralocorticoid receptor agonists?
Hyperkalaemia- high potassium levels
Spironolactone: gynaecomastia- men have larger breasts
What are the other treatments?
Alpha adrenoreceptor antagonist
e.g doxazosin
- profound hypotension
Beta blocker
- Non cardio-selective: propranolol, carvedilol
- Cardio-selective: bisoprolol, atenolol, metoprolol
Centrally acting agents
e.g moxonidine
Vasodilator
e.g hydralazine
How many weeks before pregnancy is hypertension considered chronic hypertension?
before 20 weeks
Treatment options for hypertension in pregnancy?
Antihypertensive choice:
- labetalol (mixed alpha and beta blocker)
- methyldopa (centrally acting)
- nidefipine (calcium channel blocker)
Stop ACE-i/ARB
