Cardiovascular Drugs Flashcards Preview

Anesthesiology > Cardiovascular Drugs > Flashcards

Flashcards in Cardiovascular Drugs Deck (58):
1

What are the primary effects of inhalant anesthetics on the CV system?

Vasodilation and inotropy at higher doses

2

What are the primary effects of propofol/alfaxalone/thiopenal on the CV system?

Negative inotropy and vasodilation especially at higher doses

3

What are the primary effects of opioids on the CV system?

Bradycardia; can be profound

4

What are the synthetic agonist of adrenergic receptors?

Isoproteronol, ephedrine, dobutamine, and phenylephrine

5

What are the endogenous agonist of adrenergic receptors?

Epinephrine, norepinephrine, and dopamine

6

What are the post-synaptic effects of alpha-1/2 receptors?

Vasoconstriction
Minimal Inotropy (alpha-1)

7

What are the effects of beta-1 receptors?

Inotropy, chronotropy, lusitropy, dromotropy

8

What is lusitropy and dromotropy?

Lusitropy- relaxation
Dromotropy- conduction velocity of the AV node

9

What are the effects of beta-2 receptors?

Some inotropy, vasodilation

10

What is the endogenous agonist of cholinergic receptors?

Acetylcholine

11

What are the effects of muscarinic receptors?

M1- increased gut motility
M2- increased cardiac parasympathetic tone
M3- salivation/vasodilation

12

What are synthetic cholinergic agonists?

Bethanechol and pilocarpine

13

What is the first drug that is usually used for surgical bradycardia?

Atropine

14

What are some other things you can do to correct bradycardia before giving atropine?

Stop or reduce any bradycardia inducing drugs.

(Inhalants, opioids, etc)

15

What are most bradycardias due to?

Excessive vagal tone

Brachiocephalics, visceral manipulation, ocular pressure, drugs

16

What is sometimes induced when atropine is given and will it resolve?

2nd degree AV block, typically will resolve fairly quickly

17

What can be given if a bradycardia isn't due to vagal tone?

Give a beta-agonist

18

What is isoproterenol good for?

Increasing HR while decreasing BP with an non-vagal bradycardia

19

What are causes of low BP?

Low HR/SV/CO
Low blood volume
Vasodilation with no reflex tachycardia

20

What are some ways to increase SVR?

Alpha agonists

Phenylephrine, norepi, or ephedrine

21

What are some ways to increase SV and CO?

Beta agonists

Dopamine, dobutamine, ephedrine

22

What are effects of alpha agonists?

Alpha-1/2: vasoconstriction, decrease CO/SV at high doses

Alpha-1: mild inotropy

23

What is phenylephrine used for in horses?

As a nasal spray to reduce nasal edema

24

What are some effects of ephedrine?

Bronchodilation, promotion of release of NE from terminals

25

Should ephedrine be used in "sick" animals?

No, more appropriate of elevating BP in healthy animals

26

What is an indication for using dopamine?

Increase BP and HR

27

Does dopamine case vasoconstriction or dilation?

Vasodilation- esp in kidneys, mesentary, and coronary vessels

28

Is dobutamine or dopamine more appropriate for horses, dogs, and cats?

Horses- dobutamine

29

What are the effects of dobutamine?

Intropy>chronotropy

Low doses produce desired effect in horses

30

Are the BP effects of dopamine dose dependent in small animals?

Yes

31

Are the BP effects of dopamine dose dependent in horses?

No, no change in BP until very high doses

32

What are the effects of dobutamine in small animals?

Dose dependent increase in CO but no increase in BP except at high doses

33

What are the effects of phenylephrine in small animals?

Dose dependent increases in BP, no change in CO, increased SVR in high doses

34

What are the effects of dobutamine in horses?

Rapid increase of BP at low doses with increased CO

35

What is a major issue with using norepinephrine?

Profound vasoconstriction- must maintain organ perfusion

36

When is norepinephrine usually used?

Serious hypotension esp with sepsis and shock

37

What is the pathophysiology of hypotension in septic patients?

Circulating vasodilatory mediators

38

What is norepiephrine sometimes combined with?

Dobutamine

39

When should epinephrine be used over norepinephrine?

Cardiac arrest, acute anaphylaxis, tachycardia, or bronchoconstricion

40

What receptors are more affected by epinephrine at low doses?

Beta adrenergic

41

What receptors are more affected by epinephrine at high doses?

Alpha adrenergic

42

What is vasopressin?

Antiduretic hormone (ADH)

43

When is vasopressin used?

In catecholamine resistant hypotension with shock/sepsis

44

What is a major concern with vasopressin?

Potent vasoconstriction- must maintain organ perfusion

45

What is a side effect of atropine/glycopyrrolate that contraindicates its use in cardiac patients?

Increased myocardial O2 consumption

46

What can beta agonists lead to?

Tachycardias with ventricular arrhythmias

47

What can alpha agonists lead to?

Hypertension- can be profound

48

What can vasoconstrictors lead to?

Tissue necrosis esp if injected outside of the vein

49

When are ventricular arrhythmias most common?

During the peri-anesthetic period and are usually not due to cardiac pathology

50

When should ventricular arrhythmias be treated

If they result in poor CO/BP- typically will be sustained and rapid

51

What drug is used to treat ventricular arrhythmias?

Lidocaine IV

52

What is the MOA of lidocaine?

Na channel blocker- stabilization of neuronal membranes

NOT a negative inotrope

53

What are some good side effects of lidocaine?

-Reduction of MAC and anesthetic requriements
-Improves bowel motility
-Useful for pain neuropathies
-Some free radical scavenging

54

T/F: Lidocaine is neurotoxic especially at excessive doses

True

It can also cause cardiovascular collapse at 3x toxic dose

55

What condition may cause primary hypertension?

Renal disease or catecholamine producing tumors

Typically managed with Ca channel blockers or ACE inhibitors

56

What drugs are used to manage the cardiac effects of hyperthyroidism?

Beta blockers

57

What are drugs used to treat hypertension?

Arterial dilators- hydralazine

Venous (capacitence) dilators- nitroprusside

Mixed dilators- alpha antagonists, prazosin, ACE inhibitors

58

When is nitropursside used?

Acute hypertensive emergencies (short acting infusion)