EMERGENCY ANTI-HYPERTENSIVES

 

Anti-hypertensive Starting Dose
Sodium Nitroprusside (SNP) 1-10mcg/kg/hr
Glyceryl tri-nitrate (GTN, NTG) 5-10 mcg/hr
Phentolamine
b blocker e.g. atenolol 2.5-5mg IV 
Labetalol (mixed a/b blocker)
Hydralazine 10-20mg IV
Diazoxide
Nifedipine

 

Anti-hypertensive Advantages Disadvantages
Sodium Nitroprusside (SNP) Usually predictable effect
Rapid onset/offset, Easy to titrate
Reflex tachycardia
Coronary steal
Raised ICP
Thiocyanate toxicity (crosses placenta)
Methaemoglobinaemia
V/Q mismatching
Requires protection from light
Rebound effects
Glyceryl tri-nitrate (GTN, NTG) Reduces myocardial ischaemia
Rapid onset/offset, Easy to titrate
Reflex tachycardia
?Methaemoglobinaemia
V/Q mismatching
Unpredictable effects
Phentolamine Effective
Rapid onset
Reflex tachycardia
b blocker e.g. atenolol Reduce myocardial ischaemia
Asthma
Complete heart block
Paradoxical hypertension
Labetalol (mixed a/b blocker) No reflex tachycardia
Asthma
Complete heart block
Paradoxical hypertension
Clonidine No postural hypotension
No reflex tachycardia
Safe in renal failure
Sedation
Anticholinergic side effects
Rebound effects
Hydralazine Proven safety in pregnancy Reflex tachycardia
Unpredictable effects
Difficult to titrate
Anticholinergic/antimuscarinic side effects
Decreased elimination in slow acetylators
Diazoxide Proven safety in pregnancy Reflex tachycardia
Anticholinergic side effects
Nifedipine None - do not use Reflex tachycardia
Uncontrolled/unpredictable effect