Hypertension Flashcards
What are the 3 groups of hypertension?
- Stage I hypertension
- stage II hypertension
- Severe hypertension
What are the boundaries for stage I hypertension?
- ABPM or HBPM >= 135/85 mmHg
- clinic BP >= 140/90
What is the first step you should take if a patient’s clinic blood pressure reading is >= 140/90 mmHg?
Offer ABPM or HBPM
What is the boundary for stage 2 hypertension?
- ABPM/ HBPM reading >= 150/95
- clinic BP >= 160/100
When should stage I hypertension be treated? (5 cases)
<80 years AND any of the following:
- target organ damage
- established cardiovascular disease
- renal disease
- diabetes
- 10-year cardiovascular risk (QRISK) equivalent to 10% or greater
When should stage 2 hypertension be treated?
treat all patients, regardless of age
What are 2 benefits of ambulatory blood pressure monitoring (ABPM) and home blood pressure monitoring (HBPM)?
- Helps prevent overdiagnosis of hypertension - white coat syndrome
- ABPM more accurate predictor of cardiovascular events than clinic readings
What are the boundaries for severe hypertension?
- Clinic systolic BP >180 or clinic diastolic >120
How does NICE recommend that blood pressure is measured?
- measure blood pressure in BOTH arms. Repeat if difference >20 mmHg. if remains >20, subsequent BP readings should be recorded from higher arm
- listen to heart sounds
- Take a second reading during the consultation if first reading >140/90, lower reading of two should determine management
- Offer ABPM or HBPM to any patient with BP >140/90
If after 2 blood pressure measurements in both arms the difference is still >20 mmHg what should be done?
There are pathological causes of unequal blood pressure readings from arms, e.g. supravalvular aortic stenosis. Listen to heart sounds and further investigation if very large difference noted
Under what 3 conditions should you admit the patient for specialist assessment if BP is >180/120?
- signs of retinal haemorrhage or papilloedema (accelerated hypertension)
- life-threatening symptoms such as new-onset confusion, chest pain, signs of heart failure, or acute kidney injury
- referral if phaeochromocytoma is suspected: labile or postural hypotension, headache, palpitations, pallor and diaphoresis (sweating)
What should be done if none of the reasons for admission for specialist assessment are suspected and BP is >180/120? What should be done based on the results of this?
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Arrange urgent investigations for end-organ damage e.g. bloods, urine ACR, ECG
- If target organ damage identified, consider starting antihypertensive drug treatment immediately, without waiting for results of ABPM or HBPM
- If no target organ damage identified, repeat clinic blood pressure measurement within 7 days
How does ABPM work?
- Blood pressure monitored as you move around living normal daily life
- measured for up to 24 hours
- At least 2 measurements per hour during person’s usual waking hours (e.g. 0800-2200), use average value of at least 14 measurements
*
What should be offered if ABPM is not tolerated or declined?
HBPM: home blood pressure monitoring
What does home blood pressure monitoring (HBPM) involve?
- for each BP recording, 2 consecutive measurements need to be taken, at least 1 minute apart and with person seated
- should be recorded twice daily, ideally in morning and evening
- BP should be recorded for at least 4 days, ideally for 7 days
- discard measurements taken on first day and use average value of all remaining
Why did NICE make a frther recommendation in 2019 that we should ‘CONSIDER antihypertensive drug treatment in addition to lifestyle advice for adults <60 with stage 1 hypertension and an estimated 10 year risk <10%’?
Evidence that QRISK may underestimate lifetime probability of developing cardiovascular disease
What is the importance of diagnosing hypertension?
It is an important risk factor for the development of cardiovascular disease such as ischaemic heart disease and stroke (unusual to itself cause symptoms unless very high)
What is the range in which normal blood pressure lies?
90/60 - 140/90
note that 24 hour BP average reading considers >=135/85 to be hypertension
What are the 2 categories for causes of hypertension? Which is more common?
- Primary/ essential hypertension: 90-95%
- Secondary hypertension
What is thought to be the cause of primary aka essential hypertension?
No single disease causes it, series of complex physiological changes which occur as we get older
What are 3 categories for causes of secondary hypertension?
- Renal disease
- Endocrine disorders
- Other causes
What are 4 renal causes for secondary hypertension?
- Glomerulonephritis
- Chronic pyelonephritis
- Adult polycystic kidney disease
- Renal artery stenosis
What are 6 endocrine causes of secondary hypertension?
- Primary hyperaldosteronism
- Phaeochromocytoma
- Cushing’s syndrome
- Liddle’s syndrome
- Congenital adrenal hyperplasia (11-beta hydroxylase deficiency)
- Acromegaly
What are 5 causes of secondary hypertension that fit into the ‘other’ category (i.e. not renal or endocrine)?
- Glucocorticoids
- NSAIDs
- Pregnancy
- Coarctation of the aorta
- Combined oral contraceptive pill
Over what BP might someone start to experience symptoms, and what are 3 examples of these?
- > 200/120 mmHg
- headaches
- visual disturbance
- seizures
What are 4 ways that GPs can assess for end-organ damage when assessing a patient with newly diagnosed hypertension?
- Fundoscopy: hypertensive retinopathy
- Urine dipstick: check for renal disease as cause or consequence of HTN
- ECG: check for left ventricular hypertrophy (Sokolov-Lyon: s wave depth V1 + tallest R wave heigh in V5/6 >7 big squares) or ischaemic heart disease (ST segment depression of 1.0mm or greater, ST segment elevation and alternans, u wave inversion)
- Bloods: U+Es, lipids
What are 5 tests to perform following diagnosis of hypertension?
- U+Es
- HbA1c
- Lipids - hyperlipidaemia is another risk factor for CVD
- ECG
- Urine dispstick
What cardiac abnormality can hypertension cause?
Left ventricular hypertrophy (>35mm V1 S wave + V5 or 6 R wave on ECG)
What are 3 overarching aspects of managing hypertension?
- Drug therapy with antihypertensives
- Modification of risk factors to reduce overall risk of cardiovascular disease
- Monitoring patient for development of complications of hypertension
What is the mechanism of action og ACE (angiotensin converting enzyme) inhibitors?
Inhibit the conversion of angiotensin I to angiotensin II
What are 3 common side effects of ACE inhibitors?
- Cough
- Angioedema
- Hyperkalaemia
What is a patient group in which ACE inhibitors must NOT be used?
Pregnant women
What monitoring must be performed after starting ACE inhibitors?
Renal function, check 2-3 weeks after starting due to risk of worsening renal function in patients with renovascular disease
What is the mechanism of action of calcium channel blockers?
Block voltage-gated calcium channels, relaxing vascular smooth muscle and force of myocardal contraction
What are 3 side effects of calcium channel blockers?
- Flushing
- Ankle swelling
- Headache
What are 3 side effects of thiazide type diuretics?
- Hyponatraemia
- Hypokalaemia
- Dehydration
How strong is the diuretic action of thiazide diuretics?
Very weak
What are 3 examples of thiazide diuretics?
- Chlorthalidone
- Hyrochlorothiazide
- Methyclothiazide
What is the mechanism of action of angiotensin II receptor blockers (A2RB)?
Block effects of angiotensin II at the AT1 receptor
What is a side effect of angiotensin receptor blockers?
Hyperkalaemia
When are ARBs generally used?
Situations where patients have not tolerated an ACE inhibitor, usually due to the development of a dry cough