Flashcards in Epinephrine Deck (22):
What is the drug classification of Epi?
-nonselective adrenergic agonist stimulating alpha (1&2) and beta (1&2) receptors
-receptor selectivity is dose dependent
What are the uses/indications of Epinephrine?
-bronchospasm/ bronchial asthma
-Hypersensitivity rxn (allergic rxn)
-Cardiac arrest, asystole
-V.Fib unresponsive to initial defibrillation
-Infusion to increase myocardial contractility
-also added to LAs to decrease systemic absorption and prolong DOA of the anesthetic
What is the MOA of Epi (hint: tell me by the dosages used, which receptors are being activated)?
-Beta 2: 1-2mcg/min IV (redistribution of BF to skeletal muscle)
-Beta 1: 4-5mcg/min IV
-Alpha and Beta: 10-20mcg/min IV (vasoconstriction
What is Epi the most potent activator of?
What are the routes of Epi?
SQ or IV
What is the onset of SQ and IV Epi?
SQ: 5-10 minutes
IV: 1-2 minutes
What is the DOA of Epi?
What is the standard bolus dose of Epi for resuscitation?
10mcg/kg IV (can start with 2-8mcg/kg)
-with single bolus dose CV effects dissipate after 1-5min
What are the CV effects of Epi?
-major role is BP regulation
-a1: Vasoconstriction-> Increase BP, CVP, Cardiac work, SVR
-a2: negative feedback-> decrease BP
-B1: increased contractility, HR, CO
-B2: Peripheral vasodilation-> decrease BP
-skin, mucosa, hepatic, renal (a1)
-B2- skeletal muscle
With moderate epi doses SBP tends to __________(B1, A1), and DBP tends to _________ (B2) and MAP _______ _____ _______
-stay the same
What are the cerebral effects of epi?
at clinically relevant doses, MINIMAL effects on vasoconstriction of arterioles in: Cerebral, Coronary, and Pulmonary vasculature
What are the ocular effects of Epi?
-accommodation for far vision (a1-mydriasis)
-regulation of IOP (a1, a2: increase humoral flow; B1: increase production of aqueous humor)
What are the respiratory effects of Epi?
-dilates smooth muscles of bronchial tree (B2)
-Decreased release of vasoactive mediators (histamine) in bronchial vasculature (B2)
-Reduce mucosal secretion (decongestion) (a1)
What are the GI effects of Epi?
A2: decreased digestive secretions
a, B2: decreased peristalsis, direct smooth muscle relaxation
a1: decreased splanchnic BF (drastically reduced even if BP relatively normal)
What are the GU effects of Epi?
a1-renal BF decreased; contraction of urethral sphincter
B1- increased renin release from kidney
B2- relaxation- decreases UO
B2- relaxation: inhibits labor!
What are the metabolic effects of Epi?
-Inhibit insulin release (a2)
What is the e 1/2t of Epi?
How is epi metabolized and eliminated?
-biotransformation by enzyme catechol-O-methyltransferase in the liver and kidneys; and monoamine oxidase
-inactive metabolites eliminated in the urine
What are the side effects of Epi?
-life threatening arrhythmias
-HA, nervousness, tremor
What are the contraindications to Epi?
What is the dose of EPI for hypotension?