Hypertension treatment Flashcards
what methods can be used to identify true hypertension during ‘out of hours’
must use ABPM - ambulatory blood pressure monitoring - 24/48 hours - measures as you are moving around, living your life normally, have device on you
or HBPM - home blood pressure monitoring - 1 week of measurements
NICE definition of stage 1 hypertension
Clinic blood pressure is 140/90 mmHg or higher
ABPM daytime average 135/85 mmHg or higher
NICE definition of stage 2 hypertension
Clinic blood pressure is 160/100 mmHg or higher
ABPM daytime average 150/95 mmHg or higher
NICE definition of severe hypertension
Clinic systolic blood pressure is 180 mmHg or higher or diastolic blood pressure is 110 mmHg or higher.
Risk factors contributing to hyperstension (7)
Previous MI, stroke, IHD / Family history (heart disease) Smoking Diabetes mellitus Hypercholesterolaemia Renal disease Male Age LV hypertrophy Alcohol Race
define end organ damage
damage occurring in major organs fed by the circulatory system
Left ventricular hypertrophy LVH
enlargement and thickening of the walls left ventricle
what investigations can be done to look for LVH
ECG - electrocardiogram
Echocardiogram
What is ACR? and what does it assess
Urine albumin to creatinine ratio ACR
kidney disease
Alongwith ACR what else can be used to assess kindey damage
renal ultrasound
eGFR - Glomerular Filtration Rate
In general, what treatable causes are screened for with BP measurement? (4)
Renal artery stenosis - narrowing of one of the renal arteries
Cushings disease - benign tumor called an adenoma forms in the pituitary gland
Conn’s syndrome - excess production of the hormone aldosterone from the adrenal glands, resulting in low renin levels
sleep apnoea
what is used to assess risk correctly
assign risk calculator/ Q-risk
when should treatment of hypertension be started
at an overall CVD risk of 20% /10 years
why do we treat hypertension? (2)
reduce cerebrovascular disease by 40-50%
reduce MI by 16-30% (heart attack)
How do we treat hypertension?
stepped approach
use low doses of several drugs
This approach minimises adverse events and maximises patient compliance
describe the ‘stepped approach’ for treatment of hypertension
Do not continuously change antihypertensive medication
Instead add new medication to current therapy until the target BP is achieved
what do BHS guidelines suggest for treatment of a young person with high renin
ACE Inhibitor/ARB
what is renin?
Renin converts angiotensinogen, which is produced in the liver, to the hormone angiotensin I. An enzyme known as ACE or angiotensin-converting enzyme found in the lungs metabolises angiotensin I into angiotensin II.
Angiotensin II causes blood vessels to constrict and blood pressure to increase.
what do BHS guidelines suggest for treatment of an elderly person with low
renin
Calcium Channel Blocker
Thiazide –Type Diuretic
treatment of stage 1 hypertension
Offer antihypertensive drug treatment to people aged under 80 years with >140/90 with one or more of the following:
- target organ damage
- established cardiovascular disease
- renal disease
- diabetes
- a 10-year cardiovascular risk equivalent to 20% or greater.
treatment of stage 2 hypertension
ABPM> 150/95
Offer antihypertensive drug treatment to people of any age with stage 2 hypertension.
what do you do with a patient under the age of 40 with stage 1 hypertension or greater?
get more detailed assessment of potential target organ damage
specialist evaluation of secondary causes of hypertension
what do you do with a patient over the age of 80 with stage 1 hypertension or greater?
Offer the same antihypertensive drug treatment as people aged 55–80 years, taking into account any co-morbidities.
Blood Pressure target is different
<145/85
what is the white coat effect? what should you consider for these individuals
when someone’s blood pressure is higher in medical setting than at home
Consider ABPM or HBPM as an adjunct to clinic blood pressure measurements to monitor response to treatment etc
when would a calcium - channel blocker not be a suitable treatment option
if patient has oedema or intolerance
if there is evidence of heart failure or a high risk of heart failure
what would you offer if patient couldn’t have calcium channel blocker drug
thiazide-like diuretic
step 1 hypertensive treatment for people aged >55 and to black people of African or Caribbean origin of any year
calcium-channel blocker CCB
or thiazide diuretic
step 1 treatment if under 55
angiotensin converting enzyme inhibitors ACEI/ARB
who can’t have angiotensin converting enzyme inhibitors
afro-caribbean people
women of child baring age
step 2 treatment
add thiazide-type diuretic such as clortalidone or indapamide to the CCB or ACEI/ARB
step 3 treatment
add CCB, ACEI, Diuretic together
step 4 treamtent
consider further diuretic therapy
be cautious of people with reduced estimated GFR due to risk of hyperkalaemia
consider higher dose thiaizde-like diuretic treatment if blood potassium level is higher than 4.5mmol/L
general summary of treatment of hypertension
If there are no contraindications start treatment according to age and other pathology
If over 55 years
a calcium channel blocker or diuretic
If young
An ACEI of ARB
if a single agent doesn’t control BP
Then use combination
Angiotensin Converting Enzyme Inhibitors
Competitively inhibit the actions of angiotensin converting enzyme (ACE)
RAMIPRIL, Perindopril
contraindications (reasons they shouldn’t take it) with treatment of hypertension (3)
Renal artery stenosis
Renal failure
Hyperkalaemia
Adverse drug reactions (5)
cough first dose hypotension taste disturbance renal impairment angioneurotic oedema
what drug-drug interactions occur with hypertensive drugs (3)
NSAIDs- precipitate acute renal failure by increasing BP too much
potassium supplements - hyperkalaemia - can cause abnormal heart rhythms
potassium sparing diuretics - hyperkalaemia
Angiotensin II Antagonists (ARB)
angiotensin II antagonists competitively block the actions of angiotensin II at the angiotensin AT1 receptor
examples of calcium channel blockers (2)
vasodilator - amlodipine/Felodipine
rate limiting - verapamil/diltiazem
how do calcium channel blockers work?
blocking the L type calcium channels
selectivity between vascular and cardiac L type channels
relaxing large and small arteries and reducing peripheral resistance
reducing cardiac output
Benefits (2), contraindications (3), adverse drug reactions (4) with CCBs
- Benefit in the elderly patient with systolic
Hypertension - Rarely cause postural hypotension
contraindications- Acute MI, Heart failure, bradycardia (rate limiting CCBs)
adverse drug reactions - Flushing Headache Ankle oedema - vasodilation of smaller peripheral vessels - discontinuation of capillaries - fluid seeps through gaps Indigestion and reflux oesophagitis
contraindications of thiazide-type diuretics (2)
Adverse drug reactions are not common but include gout and impotence (no effect)
less commonly used agents
centrally acting agent - methyldopa
alpha-adrenoceptor antagonist - doxazosin
methyldopa:- use, action, ADRs
Main use is in the treatment of hypertension of pregnancy
Converted to alpha-methylnoradrenaline which acts on CNS alpha- adrenoceptors which decrease central sympathetic outflow
Adverse Drug reactions
Sedation and drowsiness
Dry mouth and nasal congestion
Orthostatic hypotension
hypertension during pregnancy
second most common cause of maternal and fetal death
during norm pregnancy blood pressure falls
commonest causes of hypertension by age:-
newborn infants
infants
Newborn infants:- Renal artery thrombosis Renal artery stenosis Congenital renal malformations Coarctation
Infants – 6 years:- Renal parenchymal disease Coarctation Renal artery stenosis primary hypertension
hypertensive emergencies
Reduce mean arterial pressure by less than or equal to 25%
Patients with a hypertensive emergency are best managed with a continuous infusion of a short acting, titratable antihypertensive agent.
which type of drug delivery should not be used for hypertensive medication
sublingual and intramuscular
intermittent as required therapy, oral or IV
signs of hypertension
elevated BP
retina vascular changes
Pulmonary hypertension
arterial pressure >35 mmHg at rest
RF - family history, HIV, smoking
Signs - left parasternal heave, loud P2 sound, peripheral/pulm oedema
symptoms - SOB, fatigue, weakness, angina, syncope
Diagnosis/investigation - CXR, ECG, Echo, cMRI, routine bloods, liver ultrasound
Management - exercise, avoid pregnancy - high mortality, O2 during plane travel, flu vaccine, diuretics, anticoagulants
