Hypertension Flashcards
What is ambulatory blood pressure monitoring?
Two measurements per hour taken, average reading used
Describe the different classifications/stages of Hypertension?
- Stage 1 hypertension:
- Clinic blood pressure: 140/90 mmHg or higher
- Ambulatory bp monitoring or home bp monitoring: 135/85 mmHg or higher.
- Stage 2 hypertension:
- Clinic blood pressure:160/100 mmHg or higher
- ABPM/HBPM average blood pressure is 150/95 mmHg or higher.
- Severe hypertension:
- Clinic systolic blood pressure:180 mmHg or higher
- Clinic diastolic blood pressure is 110 mmHg or higher.
What diseases does hypertension predispose to?
Atherosclerotic changes:
- Hypertension damages the blood vessels therefore allowing for the 1st stages in plaque formation, increasing the risk of MI’s, strokes, peripheral arterial disease.
Aneurysms:
- Due to the increased pressure the aa must withstand
Cardiac Failure:
- Due to the increased afterload on the heart.
Retinopathy:
- High pressure causing damage to the small aa supplying the retina.
CKD
- Raises interglomerular pressure therefore protein is filtered and patients may have proteinuria.
- Also damages the vasculature of the kidney.
- As kidney perfusion is reduced there is increased activation of the RAAS causing increased circulating volume and BP
Define accelerated/malignant hypertension?
- A rapid sustained increase in blood pressure that is associated with target organ damage
- Diagnosed if there is SBP>200 or DBP>120 and bilateral retinal haemorrhages/exudates
Untreated mortality of 20%
Urgent treatment is needed to reduce the patients hypertension the same day.
What is primary hypertension?
Primary or essential hypertension is hypertension of an unknown cause and accounts for 95% of cases
Likely to be multifactorial
What is secondary hypertension?
Secondary hypertension is secondary to a known cause.
What are the causes of secondary hypertension?
(7)
- Adrenal cortical diseases:
- Primary hyperaldosteronism (e.g.Conn’s) - most common secondary cause
- Cushing’s, Acromegaly
- Renal aa stenosis
- Second most common secondary cause
- CKD:
- Reduced perfusion causes stimulation of the RAAs.
- Pheochromocytoma
- adrenal gland tumour will secrete all the hormones including aldosterone
- Coarctation of the aorta
- Neurogenic causes
- Raised ICP
- Pregnacy
- Pre-eclampsia
Which drugs can cause hypertension?
Recreational:
- Cocaine
- Amphetamines
- Alcohol
- Caffeine
- Corticosteroids
- Cyclosporin
- Oestrogen
- NSAIDs
Describe the RAA system?
Think Renin angiotensin aldosterone system
- Low renal perfusion stimulates the release of renin from the kidneys.
- Renin converts angiotensinogen (which is produced in the liver) into angiotensin I.
- ACE* converts angiotensin I into angiotensin II.
- Angiotensin II causes vasoconstriction of arterioles and stimulates release of aldosterone from the adrenal gland.
- Aldosterone causes reabsorption of Na+ and secretion of K+ from the distal convoluted tubule and collecting ducts. (water follows Na+ therefore increasing circulating volume)
*released from the surface of the pulmonary and renal epithelium
Describe the management of a patient with a high clinic blood pressure reading?
Patient should be given ambulatory monitoring before any treatment (two measurements per hour taken, average reading used)
What are the lifestyle changes that should be advised for a patient with hypertension?
Smoking cessation
Weight reduction
Increase exercise
Reduce excess caffeine intake
Reduce alcohol intake
Diet (reduce fats and salt eat more fruit + veg)
Describe who should receive pharmacological management for hypertension?
Stage 1 with one or more of the following:
- End organ damage
- Diabetes
- CV disease or renal disease
- High CV risk (>20% over 10 years)
All patients with Stage 2
*Stage 1: 140/90
*Stage 2: 160/100
Describe the drug regimen for hypertension?
Describe the actions of ACEI and give examples of these drugs and side effects?
- Act via RAA system
- Blocks angiotension converting enzyme and stops bradykinin be converted into an inactive metabolite.
- They reduce arteriole vasoconstriction and reduce circulating volume by reducing the reabsorption of Na+.
Examples are ramipril or lisonopril
First line in those <55 and also in diabetics (renoprotective)
S/Es:
- Dry cough (10% of pts)
- Hyperkalamia
- First dose hypotension (give at night)
- Worsened renal function in those with preiously ‘normal’ GFR - monitor U&Es
When is using an ACE Inhibitor not recommended?
In renovascular disease as it can cause a drop in renal function due to under perfusion.
Dont use in pregnancy or if hyperkalaemic, or in severe aortic stenosis
In AKI
Paradoxically it is 1st line in diabetic nephropathy.
