Norepinephrine Flashcards
Alternate Names
Noradrenaline, Levophed, leave-em-dead
Drug Class (Pharmacologic and Therapeutic)
- Pharmacologic Class - direct acting adrenergic agonist
2. Therapeutic Class - vasopressor, vasoconstrictor
Pharmacodynamics
Major action: stimulate peripheral alpha 1 adrenoreceptors -> leading to vasoconstriction (resistance arterioles, increases SVR) and venoconstriction (inc. preload) –> Increase CO, SVR, and MAP
Alternate Action: stimulates beta - 1 receptors in the heart, inc. HR and contractility
Overall Action: vasoconstriction and cardiac stimulation
Negatives: dec. blood flow to vulnerable tissues like skin, muscle, kidney.
Pharmacokinetics:
F ~ 100%; GIVEN IV ONLY. Metabolized by COMT and MAO mostly in LIVER; Metabolites excreted in URINE; Can cross the placenta but not the BBB
Half Life
1-2 minutes (titrated quickly IV)
Toxicity
excessive vasoconstriction in mesenteric vessels, peripheral arterioles causing ischemia, infarction, gangrene; reflex bradycardia
Interactions
Caution in patients taking MAOIs such as PHENELZINE (use lower dose); risk of excessive hypertension in patients taking propranolol ?
Special Considerations
Correct volume depletion with IV fluids BEFORE giving NE infusion; select infusion site carefully - extravasation is a major problem; monitor patient and BP continuously in ICU setting; use cautiously in pediatric and geriatric patients
Indications and Dose / Route
For adults with acute hypotension and shock (related to low SVR); Infuse 2-12 mcg/min
Monitor
BP, HR, infusion site, evidence of extravasation