Hypertension

Question 1

Explain hypertension to a patient

Answer 1

High blood pressure is an asymptomatic condition that can potentially cause damage to the blood vessels.

Having a high blood pressure puts you at a higher risk of having a stroke, IHD, heart failure, CKD, cognitive decline, premature death and a MI.

It is however manageable with medication to bring it down. Lifestyle factors also contribute to high blood pressure and these too should be addressed

Question 2

Consequences of hypertension

Answer 2

Stroke (2mmHg increase = 10% increased risk)
Ischaemic heart disease (2mmHg increase = 7% increased risk)
Heart failure
CKD
Cognitive decline
Premature death
MI

Question 3

Risk factors for hypertension

Answer 3

Obesity/Excess weight
Smoking
Poor diet
High cholesterol
Excess alcohol intake
Family history
Inactivity
Caribbean/African descent

Question 4

Grading hypertension

Answer 4

Grade 1 (mild) = 140-159 / 90-99

Grade 2 (moderate) = 160-179 / 100-109

Grade 3 (severe) = > 180 / >110

Isolated systolic hypertension = >140 / >90

Question 5

How is hypertension diagnosed?

Answer 5

If Clinic BP = >140 / >90

   - take a 2nd reading and use lowest
   - Offer ambulatory BP monitoring (ABPM) 

If Clinic BP = > 180 / >110

   - Start Anti-hypertensives
   - Investigate for target organ damage 
   - Assess cardiovascular risk

Refer to specialist if:

    - BP = >180/110 + Papilloedema +retinal bleed
    - BP = >180/110 + Phaechromocytoma
    - Suspecting secondary HTN

Question 6

What are the two types of hypertensive crises?

Answer 6

Hypertensive Urgency:

    - BP is acutely elevated  >180/110 
    - No acute damage to target organs
    - Severe headache
    - Dyspnoea,
    - Nose bleed
    - Severe anxiety
    - Management  = oral medications

Hypertensive emergency:

    - BP is acutely elevated > 180/110
    - Severe/permanent damage to target organs
    - Chest pain
    - Dyspnoea
    - Back pain, numbness, weakness
    - Vision changes
    - Difficulty speaking
    - Encephalopathy (oedema, ICP and dysfunction)
    - Papilloedema
    - Nephropathy
    - Management = IV medications, ICU admission

Question 7

Explain the pathophysiology of hypertension

Answer 7

CO = HR x SV BP = CO x PR

Question 8

Explain the Renin-angiotensin- aldosterone system

Answer 8

Renin causes the release of aldosterone
- Aldosterone increases the re-absorption of Na + H20

Renin converts Angiotensinogen –> Angiotensin I
ACE converts Angiotensin I —> Angiotensin II
- Angiotensin II is a potent vasoconstrictor
- Angiotensin II stimualtes aldosterone producton

Overall, the system increase CO and PR to increase BP

Question 9

How is blood pressure controlled short-term in the body?

Answer 9

Autonomic nervous system

Baroreceptors

Chemoreceptors

Atrial volume reflex

Question 10

How is blood pressured controlled long-term in the body?

Answer 10

Juxtaglomerular apparatus

Question 11

What end-organ damage is seen in hypertension?

Answer 11

EYES = Hypertensive retinopathy, retinal haemorrhage, papilloedema

BRAIN = Cerebrovascular disease (stroke/TIA)

HEART = LV hypertrophy, IHD, Heart failure

KIDNEYS = Nephropathy

Question 12

Explain the drug treatment for hypertension

Answer 12

If aged < 55 = A
If aged >55, black/African Caribbean family origin = C

If needed ….. A + C

If needed …… A + C + D

If needed …… A + C + D + further D, alpha/ beta blocker/

Question 13

What causes secondary hypertension?

Answer 13

In 10% of patients there is a specific underlying disease is is presenting with increase BP, this is known as secondary hypertension.

• Renal disease
• Cushing’s disease
• Phaechromocytoma
• Sleep apnoea
• Primary aldosteronism
• Brain tumour/Encephalitis
• Obesity

Question 14

How does cushing’s disease cause secondary hypertension?

Answer 14

Higher levels of glucocorticoids which facilitate sodium and H20 retention + consequently increase blood pressure and volume

Question 15

How does primary aldosteronism cause secondary hypertension?

Answer 15

Adrenal galnds produce excess aldosterone which facilitate sodium and H20 retention + consequently increase blood pressure and volume

Question 16

How does renal disease cause secondary hypertension?

Answer 16

In renal disease, the patient is unable to lose fluid therefore increases blood pressure/volume.

Polycystic kidney disease = an inherited condition that causes fluid to accumulate in cysts on kidneys = increased fluid retention and increased BV and BP

Glomerular disease = increased BV + BP

Renovascular hypertension is due to narrowing of the renal arteries and restricted flow to the kidneys. The kidneys assume this reduced flow is due to a decrease in blood volume/thirst and consequently retain fluid and increased BV+ BP

Question 17

How does pheochromocytoma cause secondary hypertension?

Answer 17

Pheochromcytoma is an adrenal gland tumour which stimulates noradrenaline and adrenaline release to increased BP

Question 18

How does sleep apnoea cause secondary hypertension?

Answer 18

Stopping and starting breathing decreases oxygen levels in the body and therefore the heart beats harder and faster to increase oxygen levels. This causes an increase in BP over night.

Question 19

How does obesity cause secondary hypertension?

Answer 19

As the body weigh increases, the amount of circulating blood must increase too and therefore the BV and BP increase.

Question 20

How does brain tumours/ encephalitis cause secondary hypertension?

Answer 20

The increased ICP reduced blood flow to the brain and therefore the body has to overcome this by increasing BP t ensure blood flows around the body

Question 21

List 6 other causes of temporary hypertension

Answer 21

1. Oral contraceptive pill
2. NSAID’s
3. Stimulants e.g. Cocaine
4. Antidepressants
5. Hypothyroidism
6. Coarctation of the aorta