Sodium Nitroprusside is useful only in the short term, as cyanide levels accumulate with time. Take expert advice about dosing and usage.
- Sodium nitroprusside is Na2Fe(CN)5NO - 2H2O
- In an aqueous solution, it is photosensitive and must be protected from light.
Mode of action
- Relaxation of vascular smooth muscle
- Hypotensive effect of sodium Nitroprusside is seen
within 1-2 minutes - needs close monitoring of BP
- Progressive tachyphylaxis to the hypotensive effects
- Immediate reduction of blood pressure in patients with hypertensive crises, Acute LVF and cardiac failure, Aortic dissection (with a beta-blocker e.g. Labetalol)
- Must be given as an IV infusion and never as a bolus as this can cause profound hypotension
- Initial dose is 0.3 to 1.5 microgram/kg/min. Increase slowly to 0.5-8 micrograms/kg/minute
- Stop if response unsatisfactory after 10 mins. Lower dose if on other hypotensive agents
- Advise intraarterial measurement of BP in an ITU/CCU environment
- Where BP control less urgent consider lower doses of 20-400 micrograms/minute
- Heart Failure: 10-15 micrograms/minute up to 10-200 micrograms/minute
- Protect infusion from the light.
- Severe aortic stenosis, HCM, CKD, AKI, severe B12 deficiency, Leber's optic atrophy.
- Excessive accumulation of cyanide and toxicity
- Excessive hypotension