Severe hypertension Flashcards
Signs of chronic hypertension
- Papillioedema-grade 4 hypertension
Retinopathy
Grade 1
Silver wiring
Arteries bright as oxygenated blood, veins are dark as deoygenated blood.
This disk is normal as there is a sharp edge to it, whereas in papilloedema the disk is blurred
Grade 2
AV nipping due to high pressure in the artery, it nips the vein
Grade 3
Grade 4
Disk is hard to see due to high pressure
Other hypertensive signs
- Unlike LV dilatation-thin wall, you cannot feel LVH on clinical exam. You can detect on ECGs though-tall R waves and deep q waves.
- Possibly a heave, S4 (4th heart sound), hypertension and retinopathy
Can see some flame shape haemorrhages and cotton wool spots and possibly av nipping
=grade 3 hypertension
These findings are evident of longstanding hypertension
(note-different for diabetic retinopathy which is background, pre-proliferative, and proliferative)
Secondary causes of hypertension
- Renal artery stenosis
- Cushings
- Conns
- Acromegaly
- Phaeochromocytoma
- If young person has hypertension, look for all these causes before diagnosing them with essential hypertension and giving them a drug, as may be a secondary cause.
What investigations should you do for hypertension when you don’t know cause?
- If low potassium, it makes all secondary causes more likely eg phaeo, conns, cushings, so if potassium is high it makes all those previous causes less likely
- ECG-cant find on exam as grows thick muscle inwards so look for LVH
- Urinalysis (nephritic haematuria-inflammed nephrons, nephrotic-losing protein-commonly in diabetes)
How do you regulate BP?
Adrenal tumour making lots of aldosterone, so retain salt and BP rises.
When BP increases it will suppress renin so when see low renin and high aldosteronism, think primary aldosteronism ie conns
=Renal artery stenosis
RAS-narrowed RA, so flow through here is very poor so pressure coming to kidney is low and so will have a high renin so make more angiotensin 1 and 2 so increased vasoconstriction and so fall in pressure but doesn’t go to 0 as squeezed renal efferent artery, this stops GFR from getting really low but it causes increased angiotensin.
Raised aldosterone keeps systemic BP high and retain salt etc.
Cause of RAS-calcification in older people due to cholesterol deposits. In children it is called by muscular growth hypertrophy- fibromuscular hypertrophy of vessel wall.
Coarctation of aorta does same thing but blockage is just a bit higher up. More serious than RAS as blockage it affects legs too.
Last one-primary due to tumour, secondary due to RAS
=phaeochromocytoma
Adrenaline stimulates alpha and beta adrenoreceptors and the beta receptors being stimulated causes the tachycardia.
Very different from conns which slowly pushes out aldosterone. This is where you get episodes of hypertension as adrenaline is stored up and suddenly released, can get strokes or bowel ischaemia due to sudden vasoconstriction. Adrenaline released in blasts, so very severe episodes.
=alpha blockade before beta blockade
a before b
Alpha works really quickly. Primary issue is vasoconstriction so need to give alpha blockage first to reduce this before giving beta blocker.
Give fluid before so alpha blocker doesn’t cause sudden major drop in BP.
Must be on alpha in theatre as could poke phaeo and release lost of adrenaline. So block all peripheral alpha receptors and so they can’t be affected.
What do you do now?
Then send to pathology
Use this once you have ruled out secondary hypertension.
