Autonomic Drugs-Sympathomimetic Amines (N-13)

Question 1

name the three naturally occurring catecholamines

Answer 1

EPI
NE
Dopamine

Question 2

what is the basic structure of the sympathomimetic amine

Answer 2

B-(3,4-dihydroxyphenyl)-ethylamine.

Question 3

name the three ways efficacy of a particular sympathomimetic amine is determined

Answer 3

concentration at the receptor site

affinity for specific receptors

population of receptors available for binding.

Question 4

at low doses what receptors does epi stimulate

Answer 4

beta 1 and beta 2 receptors

Question 5

what are the effects of myocardial demand and myocardial supply when administering EPI

Answer 5

it can increase myocardial demand and decrease myocardial supply.

Question 6

what are the beneficial effects of Beta -2 stimulation with EPI

Answer 6

bronchodilation
vasodilation
stabilization of mast cells
decrease in histamine release

Question 7

the beneficial effects of beta 2 and alpha stimulation of EPI will result in

Answer 7

alpha will result in decrease in bronchial secretions

net effect=decrease in airway resistance and improvement in oxygen

Question 8

what is the result of Epinephrines beta 1 effects

Answer 8

+inotropic
+chronotropic
+dromotropic

Question 9

if EPI is making the heart rate, left ventricular stroke work , stroke volume, and cardiac output increase- what happens to myocardial oxygen consumption

Answer 9

increases

Question 10

with low dose EPI (10mcg/min) - why does SVR decrease

Answer 10

peripheral vasculature vasodilation- blood flow to skeletal muscles and decreases SVR

Question 11

when EPI doses increase what effect predominates.?
systolic effect?
diastolic effect?

Answer 11

alpha
systolic increases
diastolic effect unchanged

Question 12

what happens TRANSIENTLY followed by a LONGER EPI beta 2 stimulation to potassium

Answer 12

transient hyperkalemia

longer hypokalemia as beta 2 stimulation then forces this extracellular potassium into red blood cells.

Question 13

what two drugs are considered first line therapy for shock

Answer 13

NE and dopamine

Question 14

a meta analysis showed NE and dopamine to be equally effective for shock- - and dopamine increased what two issues

Answer 14

arrhythmias and possibly increased mortality

Question 15

To a lesser extent than EPI- NE has some generalized metabolic effects such as

Answer 15

decrease in insulin production

Question 16

what are the adverse effects usually seen with NE

Answer 16

intense vasoconstriction associated with NE

Question 17

what type of sepsis does dopamine have a negative response to? and why?

Answer 17

gram negative sepsis- because the sensitivity of beta receptors is diminished due to a down regulation

Question 18

dopamine inhibits “this” leading to increase in sodium excretion and urine output

Answer 18

aldosterone

Question 19

why does dopamine increase renal blood flow, increase GFR, ad urine output.

Answer 19

it stimulates dopamine receptors in the renal arteries.

Question 20

many clinicians have abandoned the renal dopamine dosing due to

Answer 20

lack of improvement in long term morbidity and mortality

Question 21

dopamine has been implicated in several cases of severe limb ischemia-if administered through peripheral line- increase viligence is required for these 4 diseases

Answer 21

vascular diseases
diabetes
atherosclerosis
raynauds phenomenon

Question 22

if a patient is receiving “this drug” dopamine can be prolonged

Answer 22

MAOI

Question 23

which other type of drug can augment the activity of sympathomimetics drugs

Answer 23

tricyclic antidepressants

Question 24

what effects of isoproterenol on the heart limits its use for heart block unresponsive to atropine

Answer 24

tachycardia
induction of MI
arrhythmia production

Question 25

isoproterenol is a synthetic catecholamine, potent nonselective agonist of what 2 receptors

Answer 25

beta 1

beta 2

Question 26

what is isoproterenol used for

Answer 26

bradycardia with heart block
torsades de pointes ventricular tachycardia
post heart transplant for chronotropic support

Question 27

what are the cardiac and pulmonary effects seen with isoproterenol

Answer 27

potent bronchial dilator and pulmonary vasodilator

positive inotropic and chronotropic effects

Question 28

dobutamine is a modification of what drug

Answer 28

isoproterenol

Question 29

primarily dobutamine works on ___receptor with some effects on ____receptor

Answer 29

beta 1

some beta 2 effects

Question 30

dobutamine induces what responses

Answer 30

strong inotropic response

minimal chronotrophy