Released from post ganglionic sympathetic nerve endings.

Potent action on beta 1 alpha receptors . no action on beta 2 receptors.

ACTIONS:

1. Heart rate : variable, no change or increases if blood pressure is low.
2. Contractility increases.
3. Cardiac out put increases.
4. Systemic vascular resistance increases.
5. Peripheral vascular resistance increases.
6. Off set by redistribution neural uptake and metabolism by MAO.

 

ADVANTAGES:

1. Direct beta 1 agonist
2. Redistributes blood to brain and heart
3. Elicits intense alpha 1 and alpha 2 adrenergic agonism

DISADVANTAGES:

1. Decrease organ perfusion , risk of ischemia of kidney , skin , liver b, bowel and extremeties
2. Mi possible, increase afterload , heart rate , contractility, coronary spasm may be precipitated.
3. Pulmonary vasoconstriction
4. Arrhythmias
5. Risk of necrosis if extravasation

Indications for use:

1. Septic shock or vasoplegia
2. Increased systemic vascular resistance
3. Admistration by IV or Central line

DOSES:

0.015 to 0.03 mcg/kg/min IV
0.03 to 0.3 mcg/kg IV

 

WATCH FOR OLIGURIA AND METABOLIC ACIDOSIS

Nor epinephrine can be used with vasodilator
In RV failure nor epinephrine can be given directly to left atrium to bypadd lung metabolism

 

INTERACTIONS WITH MAO INHIBITORS:

Increases Hypertensive crisis.
MAO inhibitors to be stopped 2 to 3 weeks.
In patients taking MAO inhibitors indirect synapse should be avoided.

dr.ajita