Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharm II > Positive Inotropes > Flashcards

Positive Inotropes Flashcards

1
Q

Peripheral circulatory failure resulting in underperfusion of tissues

A

Shock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does shock result in?

A

Decrease oxygen delivery to tissues.

Increase in anaerobic metabolism.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 3 types of shock?

A

Hypovolemic
Septic
Cardiogenic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does septic shock result in?

A

Increased CI
Decreased PCWP
Decreased SVR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does hypovolemic shock result in?

A

Dec CI
Dec PCWP
Inc SVR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does cardiogenic shock result in?

A

Dec CI
Inc PCWP
Inc SVR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Do you have increased or decreased intracellular cAMP with congestive heart failure?

A

Decreased cAMP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Do you have a downregulation or upregulation of beta receptors with CHF?

A

Downregulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

In CHF, there is an impaired coupling between what?

A

Beta receptors and adenyl cyclase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Low cardiac output syndrome occurs when pts are coming off CPB and is a combination of what?

A 
Inadequate oxygen delivery to tissues
Hemodilution
Mild hypocalcemia
Hypomagnesemia
Kaliuresis
Tissue thermal gradients
Variable levels of systemic vascular resistance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the risk factors to Low cardiac output syndrome?

A 
DM
Increasing age
female
pre-op decreased LVEF
increased duration of CPB
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the pathophysiology of low cardiac output?

A 
Stunned myocardium (hypocontractile myocardium in response to ischemia and reperfusion)
Beta receptor down-regulation has been reported
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the treatment to low cardiac output syndrome?

A

Positive inotropes to increase the contractility of normal and stunned myocardium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the goal in critically ill patients with low cardiac output syndrome?

A

Increase levels of O2 delivery (keep SvO2 >70%)

Increase O2 consumption (arterial blood lactate level < 2 mmol/L).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which positive inotropes are cAMP dependent?

A

Beta Agonists
Dopaminergic Agonists
Phosphodiesterase Inhibitors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which positive inotropes are cAMP independent?

A

Cardiac Glycosides

Calcium

17
Q

What is the mechanism of action for cAMP dependent positive inotropes?

A 
Beta 1 agonists (promote production)
Phosphodiesterase inhibitors (inhibit metabolism)
18
Q

How do beta1 agonists work for cAMP dependent positive inotropes?

A

Act thru the G protein to simulate the production of cAMP

Initiate a cascade of reactions that increase intracellular calcium

19
Q

How do phosphodiesterase inhibitors work for cAMP dependent positive inotropes?

A

Inhibit phosphodiesterase III allowing cAMP and intracellular Ca to accumulate.

20
Q

What is the essential ion necessary for contractile function?

A

Calcium

21
Q

How do beta receptors work for cAMP dependent positive inotropes?

A

Catecholamines bind to beta receptors and activate a membrane-bound guanine nucleotide binding protein
This activates adenyl cyclase and generates cAMP.
cAMP increases Ca influx via slow channels and increases Ca sensitivity of Ca-regulatory proteins.
Increase the force of contraction and velocity of relaxation.

22
Q

What is the mechanism of action for cAMP independent positive inotropes?

A

Direct-acting inotropes:
Calcium (Increased calcium gradient across the cell) membrane
Digoxin (Inhibits Na-K ATPase)

23
Q

What are the hemodynamic effects for positive inotropes?

A

Increased contractility
Increased SV
Often decreased LVEDP and V

24
Q

What are the hemodynamic effects for “pure” beta1 agonists?

A

Increased HR
Increased A-V conduction
Decreased SVR and PVR (Beta-2 effect)
Variable effect on Myocardial O2 consumption.

25
Q

What are the hemodynamic effects for mixed alpha and beta agonists?

A

Increased vascular resistance (dose and drug related)
Increased Myocardial O2 consumption.
Increased HR

26
Q

T/F: In the failing circulation, effects of inotropes are less likely to be more pronounced.

A

False: more likely to be pronounced

27
Q

What are the indications for positive inotropes?

A

To increase SV in low flow states in which myocardial contractility is depressed.
Used in combination with other therapies to improve SV and CO by affecting preload, afterload, HR and rhythm.

Pharm II (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions