Epinephrine is both a hormone and a neurotransmitter that is naturally found in the body. It regulates heart rate, the diameters of blood vessels and air passages, and it also is triggered by the sympathetic nervous system. Epinephrine is a catecholamine.
Epinephrine is used in the CARDIAC ARREST ALGORITHM for treatment of ventricular fibrillation, pulseless ventricular tachycardia, pulseless electrical activity, and asystole. Epinephrine is also used in SYMPTOMATIC BRADYCARDIA, SEVERE HYPOTENSION, AND ANAPHYLAXIS (severe allergic reactions that cause the blood vessels to dilate and blood pressure to drop.)
Epinephrine is an alpha-adrenergic drug, which acts on the alpha one receptors in the blood vessels, causing vasoconstriction. Epinephrine is also a beta-adrenergic drug, which binds to the beta-one receptors of the heart to increase cardiac contractility and cardiac output. It is both a cardiac inotrope, which means that it increases the strength of contractions of the heart, and it is a cardiac chronotrope, which means that it increases the rate of contractions. Cardiac output is proportional to rate and volume.
Dosage of epinephrine in adult cardiac arrest is 1 mg (10 ml of a 1:10,000 solution) every 3 to 5 minutes. It is given IV or IO, and can also be given through the ET tube.
Epinephrine can be given through the endotracheal tube if necessary, and the dose is 2-2.5 mg diluted in 10ml. normal saline.
Higher doses of epinephrine may be given, up to 0.2 mg/kg, for beta-blocker overdose or calcium channel blocker overdose.
Infusions of epinephrine are given for severe hypotension or bradycardia. The dose is initially 0.1 to 0.5 mcg/kg/minute, which may be titrated upwards until a response is achieved. In severe hypotension or bradycardia, the dose can range from 2 to 10 mcg per minute infusion, titrated to response.