Some define it as BP >180/110???
British and Irish Hypertension Society 2023: elevated BP, which when sustained over the next few hours may lead to progressive life-threatening end organ damage
End-organ damage makes it an emergency - without this, it is simply 'urgency'
- MI, acute heart failure
- intracranial haemorrhage or hypertensive encephalopathy
- eclampsia
has their own methods for lowering BP:
- subarachnoid haemorrhage
- pre-eclampsia
Aim ↓ 20-25% in first 2 hours

if treatment is truly indicated...

For hypertensive emergencies, the aim is to reduce Mean Arterial Pressure (MAP*) by up to 25% in the first hour of treatment

choice of agents

sodium nitroprusside
- advantages: rapid on and offset, titratable
labetalol - alpha and beta blockade = vascular smooth muscle dilatation
- advantages: no reflex tachycardia
- predictable and titratable
nitrates - GTN. ↓ preload
- advantages: coronary vasodilator
- useful if patient is bradycardic tho
nicardipine
- advantages: considered safe in pregnancy
- disadvantages: -ve inotrope
hydralazine
- disadvantages: reflex tachycardia; avoid in cerebral disease