Norepinephrine in shock


Norepinephrine has both α- and β-adrenergic activity. Patients with severe shock may need an increase in systemic vascular resistance, and vasopressors (drugs like norepinephrine that cause vasoconstriction and therefore increase systemic vascular resistance) are given to increase preload.


However, because there is also an increase in afterload on the heart, it is also desirable to increase the stroke volume. This increase in cardiac muscle performance can overcome the increase in afterload.

Because norepinephrine is a potent vasoconstrictor, it should be administered with caution, in view of decreases in mesenteric and renal blood flow.


Which of the following is an effect of epinephrine?


Which of the following drugs belongs to the group of β-sympathomimetic drugs?


Slow i.v. infusion of a low to moderate dose of epinephrine will elicit each of the following responses EXCEPT


Which of the following statements is FALSE?