Vasoactive and Inotropic Infusions

Question 1

Dopamine 1-3 mcg/kg/min

Answer 1

Dose: 1-3 mcg/kg/min
• Stimulation of dopaminergic receptors
• Dilates renal & mesenteric vascular beds
• Direct natriuretic effects on renal tubules
–increase urine out put but does not decrease incidence of AKI or improve mortality rate!

Question 2

Dopamine 3-10 mcg/kg/min

Answer 2

• Stimulates B1 receptors
• increase cardiac contractility
• increase HR

Question 3

Dopamine 10-20 mcg/kg/min

Answer 3

• a1 receptor stimulation predominates

* Vasoconstriction

Question 4

When would you use dopamine?

Answer 4

cariogenic shock

hypotension

Question 5

Side effects of dopamine?

Answer 5

• tachycardia (correct hypovolemia first!!!)
• increase myocardial 02 consumption and may cause ventricular dysrhythmias and myocardial ischemia
• poor peripheral perfusion with higher doses.

Question 6

Dobutamine (Dobutrex)

-which receptors?

Answer 6

It is a synthetic catecholamine
Receptors:
strong B1 
   -potent inotrope (increase contractility)
   -weak chronotrope (increase HR)

Strong B2
-Vasodialation, decrease work of the heart.

Question 7

What is the indication for Dobutamine use?

Answer 7

Cardiogenic shock.

Question 8

Side affects of dobutamine?

Answer 8

• tachycardia (must have adequate preload)

- increase myocardial 02 consumption, causing ventricular dysrhythmias, myocardial ischemia.

Question 9

Dobutamine dose & titration.

Answer 9

• usually starting dose 2.5 mcg/kg/min
• titrate to patient response, usually 2.5mcg/kg/min every 30 min.

Range: 2.5-20mcg/kg/min

Question 10

Epinephrine affects which receptors?

Answer 10

Strong B1:

• inotropic - increase contractility
• chronotropic -increase HR

B2 -broncodilation

A1 -vasoconstriction

Question 11

Epinephrine use indication?

Answer 11

cardiac arrest
cariogenic shock
hypotension
anaphylaxis

Question 12

side effects of epinephrine:

Answer 12

• tachycardia
• increase myocardial o2 consumption (ventricular dysrhythmias, myocardial ischemia)
• renal and splanchnic vasoconstriction
• hyperglycemia

Question 13

Dose and titration of Epinephrine?

Answer 13

-Starting dose 2mcg/min
-titrate to patient response
1mcg/min every 5 min
taper 1mcg.min every 30 min.

usual range 2-10mcg/min
max dose 30mcg/min

Question 14

Isoproterenol (Isuprel)

What receptor does it affect?

Answer 14

• synthetic catecholamine

- Pure Beta 1, marked increase HR

Question 15

Dose & titration of isoproterenol (isuprel)?

Answer 15

start at .5mcg/min
-titrate per pt response—- 1mcg/min every 5 min.

usual dose 2-10mcg/min

Question 16

Norepinephrine (levophed)

what receptors?

Answer 16

Potent A1: vasoconstriction
Mild B1: inotropic increase contractility, chronotropic -min increase HR

*powerful vasopressor- less potent positive inotrope

Question 17

Norepinephrine (levophed)

indications:

Answer 17

hypotension from vasodilation

*septic shock, neurogenic shock

Question 18

Norepinephrine (levophed)

side effects:

Answer 18

tachycardia
HNT
increase myocardial o2 consumption (ventricular dysrhythmias, myocardial ischemia)
decrease organ perfusion

Question 19

Norepinephrine (levophed)

dosage & titration:

Answer 19

initial dose 3mcg/min

• titrate by 2mcg/min every 5 min
• taper 2mcg/min every 30 min.

max dose 30mcg/min

Question 20

Phenylephrine (Neo-synephrine)

receptors?

Answer 20

synthetic catecholamine
receptors:
a1 - pure alpha
-vasoconstriction
*no direct effect on myocardium

Question 21

Phenylephrine (Neo-synephrine)

indications?

Answer 21

hypotension from vasodilatation

• neruogenic shock
• vasogenic shock
• nitrates

Question 22

Phenylephrine (Neo-synephrine)

side effects?

Answer 22

HNT