CV Drugs

Question 1

What is the ultimate goal of the CV system?

Answer 1

Oxygen delivery to tissues

Question 2

T/F: CO can be decreased when HR is too high and too low.

Answer 2

TRUE. If too high then the ventricle isn’t able to fully fill up to eject max amount of blood. If the HR is too low, then there isn’t enough blood reaching the ventricle to be pumped out.

Question 3

What drug class alters contractility?

Answer 3

Inotropes

Question 4

What is the MOA of anticholinergics?

Answer 4

Competitive antagonists of muscarinic Ach receptors

Question 5

What effects do anticholinergic drugs have on the SA and AV node?

Answer 5

Increase firing rate of SA node (chronotropy) and conduction speed through AV node (dromotropy)

Question 6

T/F: Glycopyyrolate is used for emergency use and doesn’t cross BBB.

Answer 6

FALSE. NOT used for emergency due to slower onset of action

Question 7

What class of cardiac drug is lidocaine and what is the channel it acts on?

Answer 7

Na channel blocker-Class I. Used for VPC and Vtach

Question 8

What class of cardiac drug are beta-blockers and what are the drugs used for?

Answer 8

Class II. USed for sinus tachy or supraventricular tachycardia.

Question 9

What receptors do most pressors/inotropes act on?

Answer 9

Adrenergic receptor

Question 10

What is the exception drug that doesn’t act on adrenergic receptors?

Answer 10

Vasopressin

Question 11

What effects are seen at A1/A2 and B1/B2?

Answer 11

A1/A2: Vasoconstriction
B1: Increases inotropy and chronotropy
B2: vasodilation and bronchodilation

Question 12

What is a dose dependent inotrope that at low dose is a B agonist and at high dose is a B and A agonist?

Answer 12

Dopamine

Question 13

What is the firstline of treatment for hypotension in cats?

Answer 13

Dopamine

Question 14

What receptors does ephedrine act on?

Answer 14

Mixed agonist: primarily A but also B1/B2

Question 15

T/F: Ephedrine increases MAC.

Answer 15

True-CNS stimulation

Question 16

What inotrope is used in CPR or for anaphylactic shock?

Answer 16

Epinephrine

Question 17

What inotrope drug would you use if your patient was in refractory shock or non-responsive hypotension.

Answer 17

Norepinephrine

Question 18

What receptors does phenylephrine act on?

Answer 18

Alpha-1 agonist

Question 19

What effects will you see in your patient after phenylephrine is given?

Answer 19

Vasoconstriction and increased BP –> decreased CO and perfusion

Question 20

How will phenylephrine be useful in a patient with a nephrosplenic entrapment?

Answer 20

Phenylephrine causes constriction which can allow the spleen to contract causing the spleen to shrink and the entrapped GI to escape

Question 21

What receptors does Dobutamine act on?

Answer 21

B agonist-primarily B1–> increased inotropy, minimal chronotropy effects (mild B2 effects)

Question 22

What inotrope drug can be used to tentatively treat 3rd degree AV block until a pacemaker can be placed?

Answer 22

Isoproterenol

Question 23

What kind of drug is vasopressin?

Answer 23

Non-adrenergic sympathomimetic causing vasoconstriction via V1 receptors

Question 24

How do you respond if your patient is hypotensive?

Answer 24

Turn down the vaporizer –> if patient gets too light administer a MAC sparing drug –> give crystalloid fluid bolus –> consider giving CV drug therapy and tx underlying cause