Epinephrine is a hormone and medication used as a first line treatment for cardiac arrest. It has both alpha and beta effects on the body. At low doses, its beta effects cause vasodilation while at high doses, its alpha effects cause vasoconstriction. It is rapidly metabolized in the liver and excreted in urine. Epinephrine increases heart rate, respiratory rate, vasoconstriction, glycogenolysis, lipolysis, and muscle contraction. It is indicated for anaphylactic shock, prolonged local anesthetic effects, cardiac arrest, bronchospasm, and hypotension. Common side effects include hypertension, arrhythmias, headaches, and tremors. It should be used cautiously in
2. Its primarily a medication as well as hormone
Its an emergency drug
Its direct sympathomimetics drugs
Its 1st line drug used incardiac arrest
At low dose , beta effect (vasodilators ) on
vascular system predominant
At high dose , alpha effect ( vasoconstrictor )
are strongest
3. Chemical Structure
molecular weight = 183.2.
Epinephrine solution deteriorates rapidly
On exposure to air or light, turning pink from
oxidation to adrenochrome and brown from
the formation of melanin.
5. Metabolism
Epinephrine is rapidly inactivated in the body and
is degraded by enzymes in the liver and other
tissues.
The larger portion of injected doses is excreted in
the urine as inactivated compounds and the
remainder either partly unchanged or conjugated.
The drug becomes fixed in the tissues and is
inactivated chiefly by enzymatic transformation to
metanephrine or normetanephrine either of
which is subsequently conjugated and excreted in
the urine in the form of sulfates and
glucuronides.
7. Indication
Anaphylactic shock
Prolonged action of LA
Cardiac arrest
Bronchospasm
Chronic orthostatic hypotension
Topically , to stop bleeding
Minimal dysfunction of brain
8. Dose
La without adrenaline is 300mg or 4.4 mg/kg
With adrenaline is 500mg or 7mg/kg
Epineprine dilution of 1: 50000and 1: 100000
are considerably more effective
9. Epinephrine in lA
Advantage
Prolongs duration of action of la by keeping them in
contact with nerve fibers
Limits systemic absorption
Decreasing possibility of systemic toxicity cause rate of
metabolism will match rate of absorption
Decreases bleeding ( improves visualization )
Disadvantage
Makes injection more painful
Increase chances of local injury and necrosis
May raise blood pressure and promote arrhymias