Hypertension Flashcards
Define hypertension
The blood pressure above which the the benefits of treatment outweigh the risks in terms of morbidity and mortality.
Know the pathologic aetiology of hypertension
Primary hypertension;
- 90% of cases
- No known cause
Secondary hypertension;
- 5-10% of cases
- Chronic renal disease: fibromuscular dysplasia (in women), renal artery stenosis (in elderly), polycystic kidneys
- Pregnancy: pre-eclampsia
- Endocrine disease: Cushing’s, Conn’s, phaechromocytoma, hypo/hyperthyroidism, acromegaly
- Vascular: coarctation of the aorta
- Sleep apnoea
- Drug-induced: NSAIDs, oral contraceptive, corticosteroids
Be able to discuss the outcome of untreated hypertension
- Brain: stroke, haemorrhage, cognitive decline (dementia)
- Eyes: retinopathy
- Vascular: peripheral vascular disease
- Kidneys: renal failure
- Heart: LVH, CHD, CHF, MI
Describe the stages of hypertension
- Stage 1: 140/90mmHg
- Stage 2: 60/100mmHg
- Severe: 180/110mmHg
Describe the risk factors of hypertension
- Smoking
- DM
- Renal
- Sex: male
- Hyperlipidaemia
- Previous MI or stroke
- LVH
How does drug therapy affect the SNS to reduce BP?
- Vasoconstriction
- Reflex tachycardia
- Increased CO
Know the aetiology of hypertension
- Increase reactivity of resistance vessels, thus increased TPR
- Sodium homeostatic effect (kidneys cannot excrete right amount of sodium in primary HBP)
Know the aetiology of hypertension
- Increase reactivity of resistance vessels, thus increased TPR
- Sodium homeostatic effect (kidneys cannot excrete right amount of sodium in primary HBP)
- Age
- Family history
- Environment
- Diet
- Weight
- Alcohol intake
- Race
- Birth weight
Know the aetiology of hypertension
- Increase reactivity of resistance vessels, thus increased TPR
- Sodium homeostatic effect (kidneys cannot excrete right amount of sodium, retained fluid so BP increases)
- Age
- Family history
- Environment
- Diet
- Weight
- Alcohol intake
- Race
- Birth weight
Know the aetiology of hypertension
- Increase reactivity of resistance vessels, thus increased TPR
- Sodium homeostatic effect (kidneys cannot excrete right amount of sodium, retained fluid so BP increases)
- Age
- Family history
- Environment
- Diet
- Weight
- Alcohol intake
- Race
- Birth weight
Describe the stages of hypertension
- Stage 1: 140/90mmHg ABPM: 135/85mmHg - Stage 2: 160/100mmHg ABPM: 155/95mmHg - Severe: 180/110mmHg
Describe the diagnosis of hypertension
- Must use ABPM/HBPM
- Assess risk
Describe the diagnosis of hypertension
- Must use ABPM/HBPM
- Assess risk: history and examination
- Assess end organ damage: ECG, echocardiogram, Proteinuria, renal USS/function
- Screen for treatable causes
Describe the basic outline of the treatment of hypertension
- Assign target BP
- Stepped approach
- Use low doses of several drugs: minimises adverse events and maximises patient compliance
Describe the basic outline of the treatment of hypertension
- Assign target BP
- Stepped approach: do not continuously change drugs
- Use low doses of several drugs: minimises adverse events and maximises patient compliance
Describe the basic outline of the treatment of hypertension
- Assign target BP
- Stepped approach: do not continuously change drugs, add new drugs until target BP achieved
- Use low doses of several drugs: minimises adverse events and maximises patient compliance
Describe what should be considered when prescribing medication for stage 1 hypertension
- Offer to <80 y.o. with one or more complications
- Seek advice for <40 y.o.
- Give same treatment to >80 y.o. accounting for any co-morbidities
Discuss the stepped approach to the treatment of hypertension
Step 1;
- > 55 or black patient of any age: CCB
- Oedema, CCB intolerance, HF: thiazide-LIKE diuretic
- <55, NOT black or women of child-bearing age: ACEi/ARB
Step 2;
- CCB or ACEi/ARB: add thiazide-TYPE diuretic
Step 3;
- Add CCB, ACEi, diuretic together
Step 4 (resistant hypertension);
- Consider further diuretic therapy (low dose spironolactone) if blood K+ level <4.5mmol
- Consider high dose thiazide-LIKE diuretic if >4.5mmol
Define systolic hypertension
Systolic BP above 140mmHg.
Define diastolic hypertension
Diastolic BP above 90mmHg.
Describe drug-drug interaction to ACEi
- NSAIDs: precipitate acute renal failure
- Potassium supplements
- Potassium sparing diuretics
Define angiotensin converting enzyme inhibitors
Competitively inhibit the actions of ACE.
e.g. ramipril
Define angiotensin receptor inhibitors
Competitively block the actions ANG II at the ANG AT1 receptor.
e.g. losartan, valsartan, candesartan, irbesartan
Advantage over ACEi: no cough
Define calcium channel antagonists
e.g. vasoldilators - amlodipine, felodipine, rate limiting - verapamil, diltiazen
Define beta-adrenoreceptor antagonist
- Selectively block post-synaptic alpha-1 receptors
- Oppose vasoconstriction
Why are CCBs the drug of choice to treat hypertension?
- > 55 y.o.
- Women of child bearing age
- High compliance
- Benefit elderly with systolic hypertension
- Rarely causes postural hypotension
Define methyldopa
- Centrally acting agent
- Less common
- Used in pregnancy
Describe contraindications to CCBs
- Acute MI
- HF, bradycardia (rate limiting CCBs)
Describe adverse drug reaction to CCBs
- Flushing
- Headache
- Ankle oedema
- Indigestion and reflux oesophagitis
Describe adverse drug reaction to CCBs
- Flushing
- Headache
- Ankle oedema
- Indigestion and reflux oesophagitis
- Constipation (rate limiting CCBs)
Define thiazide diuretic
- Urinary excretion of sodium
- May take weeks to work
- Adverse reactions are uncommon but include gout and impotence
Define thiazide diuretic
- Urinary excretion of sodium
- May take weeks to work
- Adverse reactions are uncommon but include gout and impotence
e. g. indapamide, chlortalidone
Describe adverse drug reaction to CCBs
- Flushing
- Headache
- Ankle oedema
- Indigestion and reflux oesophagitis
- Constipation (rate limiting CCBs)
Describe adverse drug reaction to alpha-adrenoreceptor antagonists
- First dose hypotension
- Dizziness
- Dry mouth
- Headache
Describe adverse drug reactions to methyldopa
- Sedation and drowsiness
- Dry mouth and nasal congestion
- Orthostatic hypotension
